Title of Invention	ENGINE EXHAUST RECYCLING APPARATUS
Abstract	ABSTRACT "ENGINE EXHAUST RECYCLING APPARATUS" An engine exhaust recycling apparatus for a liquid-cooled type engine including an engine body (11) having an air intake port (23), an exhaust port (24) and coolant gaskets (71, 72) through which coolant passes through being provided thereto, said engine exhaust recycling apparatus comprising an exhaust recycling path (80) connected to the air intake part (23) and exhaust port (24) of said engine body (11), characterized in that said exhaust recycling path (80) is provided with an exhaust recycling control valve (81) mounted to said engine body such that the coolant is guided through said coolant jackets (71, 72) to cool said exhaust recycling control valve (81). Fig. 2

Title of Invention

ENGINE EXHAUST RECYCLING APPARATUS

Abstract

ABSTRACT "ENGINE EXHAUST RECYCLING APPARATUS" An engine exhaust recycling apparatus for a liquid-cooled type engine including an engine body (11) having an air intake port (23), an exhaust port (24) and coolant gaskets (71, 72) through which coolant passes through being provided thereto, said engine exhaust recycling apparatus comprising an exhaust recycling path (80) connected to the air intake part (23) and exhaust port (24) of said engine body (11), characterized in that said exhaust recycling path (80) is provided with an exhaust recycling control valve (81) mounted to said engine body such that the coolant is guided through said coolant jackets (71, 72) to cool said exhaust recycling control valve (81). Fig. 2

Full Text	FORM 2 THE PATENTS ACT 1970 [39 OF 1970] & THE PATENTS (AMENDMENT) RULES, 2006 COMPLETE SPECIFICATION [See Section 10; rule 13] "ENGINE EXHAUST RECYCLING APPARATUS" HONDA MOTOR CO., LTD., a corporation of Japan, of 1-1, Minamiaoyama 2-chome, Minato-ku, Tokyo, Japan, The following specification particularly describes the invention and the manner in which it is to be performed: [Detailed Description of the Invention] [0001] [Technical Field of the Invention] The present invention relates to an engine exhaust recycling apparatus in which an exhaust recycling control valve is provided in an exhaust recycling path connecting an air intake system which is connected to an air intake port of an engine body and an exhaust port of the engine body. [0002] [Description of the Related Art] An exhaust recycling apparatus in which an exhaust recycling control valve is provided at the midsection of an exhaust recycling path for recycling part of exhaust passing through an exhaust port of an engine body to the air intake system is already known, for example, in Patent Document 1. [0003] [Patent Document 1] JP-UM-B-61-43969 [0004] [Problems to be Solved by the Invention] In the technology described above, the exhaust recycling control valve is mounted to the cylinder block of the engine. However, since the engine is air-cooled type, and in addition, since the exhaust recycling control valve is mounted to the cylinder block in the vicinity of the exhaust port, the temperature of the exhaust recycling control valve increases to a relatively high value, and hence measure for improve the heat-resistance property is required. In addition, in order to improve the efficiency to purify exhaust air, it is desirable to improve controllability of opening by employing an actuator of an electric type for the exhaust recycling control valve. However, it is difficult to employ the electrical actuator under the circumstance in which the temperature of the exhaust recycling control valve increases to a relatively high value as described above. [0005] In view of such circumstances, it is an object of the present invention to provide an engine exhaust recycling apparatus in which the exhaust recycling control valve can be used in the state of being at relatively low temperature. [0006] [Means for Solving the Problems] In order to achieve the object described above, the invention according to Claim 1 is an engine exhaust recycling apparatus in which in which an exhaust recycling control valve is provided in an exhaust recycling path connecting an air intake system which is connected to an air intake port of an engine body and an exhaust port of the engine body, characterized in that the engine body is of a liquid-cooled type configured to be cooled by recycling of a coolant, and the coolant is guided to the exhaust recycling control valve to cool the exhaust recycling control valve. [0007] In the arrangement according to Claim 1, since the exhaust recycling control valve can be cooled by coolant and hence the exhaust recycling control valve can be used in a state of being at relatively low temperature, measure for improving the heat resistant property is not necessary, and the efficiency to purify exhaust air can be improved by improving the opening controllability by employing an actuator of an electric type for the exhaust recycling control valve. [0008] In addition to the structure of the invention according to Claim 1, the invention of Claim 2 is characterized in that a coolant jacket for distributing coolant is provided on the engine body, and the exhaust recycling control valve is mounted to an outer wall of the engine body so as to be cooled by the coolant from the coolant jacket. In this arrangement, the exhaust recycling control valve is mounted directly to the engine body while enabling to be used in a state of being at relatively low temperature, so that the entire engine including the exhaust recycling control valve can be configured to a compact structure. [0009] In addition to the structure of the invention according to Claim 1, the invention of Claim 3 is characterized in that the exhaust recycling control valve includes a valve portion which can open and close the midsection of the exhaust recycling path and an electrical actuator for driving the valve portion connected to the valve portion, and in that the coolant is guided to the portion of a valve housing provided on the valve portion on the side of the electrical actuator. In this arrangement, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator. [0010] In addition to the structure of the invention according to Claim 1, the invention of Claim 4 is characterized in that the coolant jacket for distributing the coolant is provided on a cylinder block constituting part of the engine body, and the outer wall of the cylinder block having the inner surface thereof facing the coolant jacket is formed with an opening which communicates with the coolant jacket and with a mounting portion surrounding the opening, in that the exhaust recycling control valve including the valve portion having a valve body which can open and close the midsection of the exhaust recycling path and is accommodated in the valve housing and the electrical actuator for driving the valve body connected to the valve portion is mounted to the mounting portion so as to close the opening by the portion of the valve housing on the side of the electrical actuator. [0011] In this arrangement of Claim 4, in a state in which the exhaust recycling control valve is not mouthod, the liquid-cooled jacket of the cylinder block is opened toward the outside via the opening, and thus formation of the liquid-cooled jacket when casing the cylinder block can easily be performed. Furthermore, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator and, in addition, the structure for cooling the exhaust recycling control valve may be simplified to improve its assemblability. [0012] [Mode for Carrying Out the Invention] A mode for carrying out the invention will be described based on an embodiment of the present invention shown in the drawings. [Brief Description of the Drawings] [Fig. 1] Fig. 1 is a side view of a motorcycle. [Fig. 2] Fig. 2 is a side view of a part of an engine. [Fig. 3] Fig. 3 is a cross-sectional view taken along the line 3-3 in Fig. 2. [Fig. 4] Fig. 4 is a cross-sectional view taken along the line 4-4 in Fig. 3. [Fig. 5] Fig. 5 is a cross-sectional view taken along the line 5-5 in Fig. 3. [0013] Fig. 1 to Fig. 5 show an embodiment of the present invention. Fig. 1 is a side view of a motorcycle; Fig. 2 is a side view of a part of an engine; Fig, 3 is a cross-sectional view taken along the lien 3-3 in Fig. 2; Fig. 4 is a cross-sectional view taken along the line 4-4 in Fig. 3; and Fig. 5 is a cross-sectional view taken along the line 5-5 in Fig. 3. [0014] In Fig. 1, a motorcycle V includes a front wheel WF and a rear wheel WR at the front and the rear of a vehicle body, and the front wheel WF is rotatably supported at the lower end of a front fork 7, which can be rotated leftward and rightward by a steering handle 6. The rear wheel WR is rotatably supported at the rear end of a swing arm 8, which is supported by the vehicle body so as to be capable of swinging upward and downward, and a rear cushion 9 is provided between the swing arm 8 and the vehicle body. [0015] Disposed between the front wheel WF and the rear wheel WR is a power unit P which is to be mounted to the vehicle body. The power unit P includes a direct gasoline-injection engine E of four-cycle liquid-cooled type having a cylinder axis C inclined upward and frontward, and a transmission M for changing the speed of the output of the engine E, and the output of the transmission M is transmitted to the rear wheel WR by a chain (not shown). [0016] In Fig. 2 to Fig. 4, an engine body 11 of the engine E includes a crankcase 12, a cylinder block 13 to be connected to the crankcase 12, a cylinder head 14 to be connected to the cylinder block 13 on the opposite side from the crankcase 12, and a head cover 15 to be connected to the cylinder head 14 on the side opposite from the cylinder block 13, and is mounted to the motorcycle V with the cylinder head 14 side slightly upward. [0017] A piston 17 to be fitted slidably into a cylinder bore 16 provided on the cylinder block 13 is connected to a crankshaft 10 (not shown) rotatably supported by the crankcase 12 via a connecting rod 18 and a crankpin (not shown), and a combustion chamber 19 to which the top of the piston 17 is exposed is defined between the cylinder block 13 and the cylinder head 14. [0018] The cylinder head 14 includes a pair of intake valve ports 20.... opening on the ceiling surface of the combustion chamber 19, an air intake port 23 commonly communicated to those intake valve ports 20... and opening on the upper side surface of the cylinder head 14, a single exhaust valve port 22 opening on the ceiling surface of the combustion chamber 19, an exhaust port 24 communicating to the exhaust valve port 22 and opening on the lower side surface of the cylinder head 14, and an injector 25 for directly injecting fuel into the combustion chamber 19 with compressed air disposed on the axis of the cylinder bore 16, that is, on the cylinder axis C. [0019] An ignition plug 26 is mounted to the cylinder head 14 so as to be exposed in the combustion chamber 19 at the position other than the intake valve ports 20... and the exhaust valve port 22. [0020] The cylinder head 14 includes a pair of openable and closable intake valves 27... which can open and close both of the intake valve ports 20..., and an openable and closable exhaust valve 2 9 which can open and close the exhaust valve port 22. [0021] The intake valves 27... are slidably fitted to guide cylinders 30... secured to the cylinder head 14 respectively, and valve springs 32... are provided between retainers 31... and the cylinder head 14, which are fixed respectively to the ends of the intake valves 27. . . projected from the guide cylinders 30.... The intake valves 27... are urged in the valve-closing direction by a spring force exerted by the valve springs 32.... The exhaust valve 29 is slidably fitted into a guide cylinder 33 fixed to the cylinder head 14, and a valve spring 35 is provided between a retainer 34 and the cylinder head 14 which are fixed to the end of the exhaust valve 2 9 projected from the guide cylinder 33. The exhaust valve 29 is urged in the valve-closing direction by a spring force exerted by the valve spring 35. [0022] Intake-side and exhaust-side rocker shafts 36, 37 extending in parallel with the axis of the crankshaft are supported by the head cover 15, and an intake-side first rocker arm 38 pivotably supported by the intake-side rocker shaft 36 abuts against the end of the intake valves 27... and an exhaust-side first rocker arm 39 pivotably supported by the exhaust-side rocker shaft 37 abuts against the end of the exhaust valve 29. [0023] On the other hand, both ends of a camshaft 41 extending in parallel with the intake-side and exhaust-side rocker shafts 36, 37 are rotatably supported by the cylinder block 13 and a cover 40 secured to the cylinder block 13 via ball bearings 42, 43, and a cam chain 45 for reducing the rotational power from the crankshaft to 1/2 and transmitting the reduced power is wound around a driven sprocket 44 mounted to the camshaft 41 so as not to rotate with respect to each other. [0024] An intake-side cam 46 and an exhaust-side cam 47 are fixed to the camshaft 41, and an intake-side second rocker arm (not shown) driven by the intake-side cam 46 and an exhaust-side second rocker arm 49 driven by the exhaust-side cam 47 are pivotably supported by the cylinder block 13. The pivotal movement of the intake-side second rocker arm is transmitted to the intake-side first rocker arm 38 via an intake-side push rod 50, and the pivotal movement of the exhaust-side second rocker arm 49 is transmitted to the exhaust-side first rocker arm 39 via an exhaust-side push rod 51. [0025] The injector 25 is supplied with compressed air from a compressed air pump 54 having an operational axis extending in parallel with the cylinder axis C of the engine body 11 and being mounted to the lower side wall of the cylinder block 13, and a power is transmitted from the camshaft 41 to the compressed air pump 54. [0026] In other words, a drive sprocket 55 is integrally formed with the driven sprocket 44 mounted to the camshaft 41 so as not to rotate with respect to each other, and a power is transmitted to the compressed air pump 54 via an endless chain 56 wound around the drive sprocket 55. In this manner, the compressed air pump 54 is of a reciprocating type having the operational axis extending in parallel with the cylinder axis C, and a rotational power transmitted from the chain 56 is converted into a reciprocating motion of the compressed air pump 54 via a crank mechanism, not shown. [0027] The injector 25 includes an air-fuel injection valve 58 having a nozzle 57 which projects into the combustion chamber 19 and is mounted to the cylinder head 14, and a fuel injection valve 59 connected to the air-fuel injection valve 58 so as to inject fuel from behind into the air-fuel injection valve 58. The air-fuel injection valve 58 injects fuel together with compressed air directly into the combustion chamber 19. [0028] The cylinder head 14 includes a fitting hole 60, to which the nozzle 57 is hermetically fitted, and an insertion cylinder 61 having an inner diameter larger than the fitting hole 60 and continuing coaxially to the fitting hole 60, both provided coaxially with the cylinder axis C. The air-fuel injection valve 58 is inserted into the insertion cylinder 61 until the nozzle 57 is fitted hermetically into the fitting hole 60 and abuts against an annular shoulder 62 formed between the fitting hole 60 and the insertion cylinder 61 with the intermediary of a wave spring washier 63. [0029] On the other hand, the head cover 15 is formed integrally with a cylindrical injector housing 64 which fits on and holds the fuel injection valve 59 and clamps the air-fuel injection valve 58 with respect to the cylinder head 14, so that the extremity of the injector housing 64 abuts against the rear end of the air-fuel injection valve 58 when combining the head cover 15 to the cylinder head 14. A clamping plate 65 for clamping the rear end of the fuel injection valve 59 with respect to the injector housing 64 is secured to the rear end of the injector housing 64. [0030] An annular fuel chamber 66 communicating with the interior of the fuel injection valve 59 is defined between the injector housing 64 and the fuel injection valve 59, and a pair of sealing members 67, 68 for clamping the fuel chamber 66 from both sides are interposed between the fuel injection valve 59 and the injector housing 64, In addition, the head cover 15 is formed with a fuel supply path 69 communicating with the fuel chamber 66, and fuel which is adjusted to a constant pressure is supplied to the fuel chamber 66 via the fuel supply path 69. [0031] An annular air chamber 70 communicating with the interior of the air-fuel injection valve 58 is defined between the distal end of the fuel injection valve 59 and the rear end of the air-fuel injection valve 58 and the injector housing 64. Compressed air from the compressed air pump 54 is supplied to the air chamber 70. [0032] The engine body 11 is of a liquid-cooled type configured to be cooled by recycling of coolant. Coolant jackets 71, 72 for distributing coolant are provided respectively on the cylinder block 13 and the cylinder head 14 of the engine body 11. An air intake system 74 including an air intake pipe 73 is connected to the air intake port 23 of the cylinder head 14, and the downstream end of an exhaust pipe 75 connected to the exhaust port 24 of the cylinder head 14 is connected to an exhaust muffler 76 to be disposed on the right side of the rear wheel WR. [0033] Part of exhaust passing through the exhaust port 24 is to be recycled toward the air intake system 74 via an exhaust recycling path 80, and an exhaust recycling control valve 81 is disposed at the midsection of the exhaust recycling path 80. [0034] An upper recycling path 80a of the exhaust recycling path 80 located between the exhaust recycling control valve 81 and the exhaust port 24 is defined within an upstream duct line 82 provided between the cylinder head 14 and the exhaust recycling control valve 81, and a downstream duct line 80b of the exhaust recycling path 80 located between the exhaust recycling control valve 81 and the air intake system 74 is defined within a downstream duct line 83 provided between the air intake pipe 73 in the air intake system 74 and the exhaust recycling control valve 81. [0035] Referring also to Fig. 5, the exhaust recycling control valve 81 includes a valve portion 84 which can open and close the midsection of the exhaust recycling path 80 and an electrical actuator 85 for driving the valve portion 84 connected thereto, and coolant passing through the coolant jackets 71, 72 provided on the engine body 11, in particular, coolant passing through the coolant jacket 71 of the cylinder block 13 of the engine body 11 is guided to the exhaust recycling control valve 81 mounted to the cylinder block 13 so as to cool the exhaust recycling control valve 81. [0036] The valve portion 84 of the exhaust recycling control valve 81 includes a valve housing 86, a valve seat member 87 to be fixed within the valve housing 86, a valve body 88 which can get seated on the valve seat member 87, and a return spring 89 for exerting a spring force to make the valve body 88 seated on the valve seat member 87. [0037] The valve housing 86 is formed into a shouldered cylindrical shape having a bulkhead portion 86a at the midsection in the axial direction. An opening at one end in the axial direction is closed in a liquid-tight manner by screwing a lid member 90 into the valve housing 86. The valve seat member 87 is fixed to the valve housing 86 so as to be interposed between a shoulder 86b provided on the inner surface of the valve housing 86 between the bulkhead portion 86a and the lid member 90 and exposing toward the lid member 90 and a stop ring 91 mounted to the inner surface of the valve housing 86 and engaged with the outer periphery of the valve seat member 87 at one end. In addition, an upstream valve chamber 92 is defined in the valve housing 86 between the valve seat member 87 and the lid member 90, and a downstream valve chamber 93 is formed between the valve seat member 87 and the bulkhead portion 86a. [0038] The valve body 88 can block between the upstream and the downstream valve chambers 92, 93 by getting seated at the center of the valve seat member 87 in the upstream valve chamber 92, and is provided integrally at one end of a valve shaft 94 loosely passing through the center of the valve seat member 87. The valve shaft 94 passes through the bulkhead portion 86a so as to be capable of moving in the axial direction, and a cylindrical guiding member 95 being in sliding contact with the outer periphery of the valve shaft 94 is mouthed to the bulkhead portion 86a so as to guide the movement of the valve shaft 94 and preventing leakage of gas from the downstream valve chamber 93. [0039] A retainer 96 is mounted to the valve shaft 94 at the other end, and the return spring 89 is disposed between a spring receiving seat 97 received by the bulkhead portion 86a and the retainer 96 in a contracted state. [0040] The electrical actuator 85 is configured to actuate a drive shaft 98 which abuts coaxially against the other end of the valve shaft 94 in the axial direction, for example, by an output of a step motor, and a housing 99 of the electrical actuator 85 is connected to the other end of the valve housing 86 so as to define a spring chamber 100 for accommodating the return spring 89 with respect to the bulkhead chamber 86a. [0041] In this manner, the amount of passage of exhaust air between the upstream valve chamber 92 and the downstream valve chamber 93 is controlled by driving the valve shaft 94 in the axial direction against a spring force of the return spring 89 by the operation of the electrical actuator 85. [0042] The upstream end of the upstream duct line 82 defining the upstream recycling path 80a of the exhaust recycling path 80 is inserted into the cylinder head 14 so as to be communicated with the exhaust port 24 with the intermediary of an annular sealing member 101 with respect to the cylinder head 14, and the sealing member 101 is tightly clamped and thus seals between the upstream duct line 82 and the cylinder head 14 by screwing and tightening a cylindrical holding member 102 surrounding the upstream end of the upstream duct line 82 into the cylinder head 14. Accordingly, the upstream end of the upstream duct line 82 can be slid in the axial direction, and is connected hermetically to the cylinder head 14. [0043] The downstream end of the upstream duct line 82 is screwed into the valve housing 86 of the exhaust recycling control valve 81 so as to communicate the downstream end of the upstream recycling path 80a with the upstream valve chamber 92, and an annular sealing member 103 is interposed between the valve housing 86 and the upstream duct line 82. [0044] The downstream duct line 83 defining the downstream recycling path 80b of the exhaust recycling path 80 is provided with a flange 83a at the upstream end thereof, and the flange 83a is secured to the valve housing 86 by a pair of bolts 104, 104 so as to communicate the upstream end of the downstream recycling path 80b with the downstream valve chamber 93. The downstream duct line 83 is provided with a flange 83b at the downstream end, and the downstream end of the downstream recycling path 80b is brought into communication with the interior of the air intake pipe 73 by the flange 83b being secured to the air intake pipe 73 of the air intake system 74 with a plurality of bolts 105.... [0045] The outer wall of the cylinder block 13, facing the coolant jacket 71 at the inner surface thereof, is formed with an opening 106 which communicates with the coolant jacket 71, and is provided with a mounting portion 107 surrounding the opening 106. The exhaust recycling control valve 81 is mounted to the mounting portion 107 with a plurality, for example, a pair of bolts 108, 108 so as to close the opening 106 by the portion of the valve housing 86 on the side of the electrical actuator 85. [0046] In other words, a flange 110 corresponding to the mounting portion 107 is integrally formed on the portion of the valve housing 86 corresponding to the spring chamber 100, and the flange 110 including a gasket 109 interposed with respect to the mounting portion 107 is secured to the mounting portion 107 with the bolts 108, 108. Accordingly, the valve housing 86, or the exhaust recycling control valve 81 is mounted to the cylinder block 13 so as to close the opening 106 by the flange 110 of the valve housing 86. [0047] In addition, the flange 110 is formed with an opening hole 111 communicating with the spring chamber 100 and a groove 112 defining a passage between the opening hole 111 and the gasket 109 for opening the opening hole 111 toward the outside. [0048] Subsequently, the operation of this embodiment will be described. Since coolant is guided to the exhaust recycling control valve 81 provided in the exhaust recycling path 80 connecting the air intake pipe 73 of the air intake system 74 connected to the air intake port 23 of the engine body 11 of a liquid-cooled type configured to be cooled by recycling of coolant and exhaust port 24 of the engine body 11, and thus the exhaust recycling control valve 81 can be cooled by coolant/ the exhaust recycling control valve 81 can be used in a state of being at a relatively low temperature. Therefore, measure for improving the heat resistant property is not necessary, and the efficiency of purifying exhaust air may be improved by enhancing controllability of opening by employing the actuator 85 of an electric type for the exhaust recycling control valve 81. [0049] In addition, since the exhaust recycling control valve 81 is mounted to an outer wall of the cylinder block 13 so as to be cooled by the coolant from the coolant jacket 71 provided on the cylinder block 13 of the engine body 11, the exhaust recycling control valve 81 is mounted directly to the cylinder block 13 of the engine body 11 while enabling to be used in a state of being at relatively low temperature, so that the entire engine E including the exhaust recycling control valve 81 can be configured to a compact structure. [0050] Since the exhaust recycling control valve 81 includes the valve portion 84 which can open and close the midsection of the exhaust recycling path 80 and the electrical actuator 85 for driving the valve portion 84 connected to the valve portion 84, and the coolant from the coolant jacket 71 is guided to the portion of the valve housing 86 provided on the valve portion 84 on the side of the electrical actuator 85, the valve portion 84 of the exhaust recycling control valve 81 is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion 84 to the electrical actuator 85 is effectively held down to control increase in temperature of the electrical actuator 85. [0051] The outer wall of the cylinder block 13 having the inner surface facing the coolant jacket 71 is formed with the opening 106 which communicates with the coolant jacket 71 and with the mounting portion 107 surrounding the opening 106, and the exhaust recycling control valve 81 is mounted to the mounting portion 107 so that the opening 106 is closed by the portion of the valve housing 86 provided on the valve portion 84 on the side of the electrical actuator 85. [0052] In other words, in a state in which the exhaust recycling control valve; 81 is not mouthed, the liquid-cooled jacket 71 of the cylinder block 13 is opened toward the outside via the opening 106, and thus formation of the liquid-cooled jacket 71 when casing the cylinder block 13 can easily be performed. [0053] In addition, the structure for cooling the exhaust recycling control valve 81 may be simplified to improve its assemblability. [0054] Although the embodiment of the present invention has been described thus far, the present invention is not limited thereto, and various modifications in design may be performed without departing from the scope of the present invention stated in appended Claims. [0055] [Advantages of the Invention] As described above, according to Claim 1, since the exhaust recycling control valve can be cooled by coolant and hence the exhaust recycling control valve can be used in a state of being at relatively low temperature, measure for improving the heat resistant property is not necessary, and the efficiency to purify exhaust air can be improved by improving the opening controllability by employing an actuator of an electric type for the exhaust recycling control valve. [0056] According to the invention of Claim 2, the exhaust recycling control valve is mounted directly to the engine body while enabling to be used in a state of being at relatively low temperature, so that the entire engine including the exhaust recycling control valve can be configured to a compact structure. [0057] According to the invention of Claim 3, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator. [0058] According to the invention of Claim 4, formation of the liquid-cooled jacket when casing the cylinder block can easily be performed. Furthermore, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator ef f ectiyely and, in addition, the structure for cooling the exhaust recycling control valve may be simplified to, improve its assemblability. [Reference Numerals] 11...engine body 23...air intake port 24...exhaust port 71, 72...coolant jacket 74...air intake system 80...exhaust recycling path 81...exhaust recycling control valve 84...valve portion 85...electrical actuator 86...valve housing 88...valve body 106...opening 107...mounting portion E...engine The present invention relates to an engine exhaust recycling apparatus [0001] [Technical Field of the Invention] The present invention relates to an engine exhaust recycling apparatus in which an exhaust recycling control valve is provided in an exhaust recycling path connecting an air However,it is difficult to employ the electrical actuator under the circumstance in which the temperature of the exhaust recycling control valve increases to a relatively high value as described above. [0005] In view of such circumstances, it is an object of the present invention to provide an engine exhaust recycling apparatus in which the exhaust recycling control valve can be used in the state of being at relatively low temperature. [0006] [Means for Solving the Problems] In order to achieve the object described above, the invention according to first aspect is an engine exhaust recycling apparatus in which in which an exhaust recycling control valve is provided in an exhaust recycling path connecting an air intake system which is connected to an air intake port of an engine body and an exhaust port of the engine body, characterized in that the engine body is of a liquid-cooled type configured to be cooled by recycling of a coolant, and the coolant is guided to the exhaust recycling control valve to cool the exhaust recycling control valve. [0007] In the arrangement according to first aspect since the exhaust recycling control valve can be cooled by coolant and hence the exhaust recycling control valve can be used in a state of being at relatively low temperature, measure for improving the heat resistant property is not necessary, and the efficiency to purify exhaust air can be improved by improving the opening controllability by employing an actuator of an electric type for the exhaust recycling control valve. [0008J In .addition to the structure of the invention according :o first aspect the invention of another aspect is characterized in that a coolant jacket for distributing coolant is provided on the. engine body, and the exhaust recycling control valve is mounted to an outer wall of the engine body so as to be cooled by the coolant from the coolant jacket. in this arrangement, the exhaust recycling control valve is mounted directly to the engine body while enabling to be used in a state of being at relatively low temperature, so that the entire engine including the exhaust recycling control valve can be configured to a compact structure. [0009] In addition to the. structure of the invention according to first aspect, the invention of another aspect is characterized in that the exhaust recycling control valve includes a valve portion which can open and close the midsection of the exhaust recycling path and an electrical actuator for driving the valve portion connected to the valve portion, and in that the coolant is guided to the portion of a valve housing provided on the valve portion on the side of the electrical actuator. In this arrangement, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator. [0010] In addition to the structure of the invention according to first aspect, the invention of another aspect is characterized in thai the coolant jacket for distributing the coolant is provided on a cylinder block constituting part of the engine body, and the outer wall of the cylinder block having the inner surface thereof facing the coolant jacket is formed with an opening which communicates with the coolant jacket and with a mounting portion surrounding the opening, in that the exhaust recycling control valve including the valve portion having a valve body which can open and close the midsection of the exhaust recycling path and is accommodated in the valve housing and the electrical actuator for driving the valve body connected to the valve portion is mounted to the mounting portion so as to close the opening by the portion of the valve housing on the side of the electrical actuator. [0011] In this arrangement of another aspect, in a state in which the opening 106, and thus formation of the liquid-cooled jacket 71 when casing the cylinder block 13 can easily be performed. [0053] In addition, the structure for cooling the exhaust recycling control valve 81 may be simplified to improve its assemblability. [0054] Although the embodiment of the present invention has been described thus far, the present invention is not limited thereto, and various modifications in design may be performed without departing from the scope of the present invention stated in appended Claims. [0055] [Advantages of the Invention] As described above, according to first ' aspect, since the exhaust recycling control valve can be cooled by coolant and hence the exhaust recycling control valve can be used in a state of being at relatively low temperature, measure for improving the heat resistant property is not necessary, and the efficiency to purify exhaust air can be improved by improving the opening controllability by employing an actuator of an electric type for the exhaust recycling control valve. [0056] According to the invention of another aspect, the exhaust recycling control valve is mounted directly to the engine body While enabling to be used in a state of being at relatively low temperaturer so that the entire engine including the exhaust recycling control valve can be configured to a compact structure.. [0057] According to the invention of another aspect, the Valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is"effectively held down to control increase in temperature of the electrical actuator. [0058] According to the invention of another aspect, formation of the liquid-cooled jacket when casing the cylinder block can easily be performed. Furthermore, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator effectively and, in addition, the structure for cooling the exhaust recycling control valve may be -simplified to improve its assemblability. WE CLAIM: 1. An engine exhaust recycling apparatus for a liquid-cooled type engine including an engine body (11) having an air intake port (23), an exhaust port (24) and coolant gaskets (71, 72) through which coolant passes through being provided thereto, said engine exhaust recycling apparatus comprising an exhaust recycling path (80) connected to the air intake part (23) and exhaust port (24) of said engine body (11), characterized in that said exhaust recycling path (80) is provided with an exhaust recycling control valve (81) mounted to said engine body such that the coolant is guided through said coolant jackets (71, 72) to cool said exhaust recycling control valve (81). 2. An engine exhaust recycling apparatus as claimed in claim 1, wherein said exhaust recycling control valve is mounted to the outer wall of said engine body so as to be cooled by the coolant from the coolant gaskets. 3. An engine exhaust apparatus as claimed in claim 1, wherein said exhaust recycling control valve (81) includes a valve portion (84) provided at the midsection of said exhaust recycling path (80), an electrical actuator (85) driving said valve portion (84), and a valve housing (86) provided on the valve portion (84) along the side of said electrical actuator (85) where said coolant is guided through said coolant jackets (71, 72). 4. An engine exhaust recycling apparatus as claimed in claim 1, wherein the coolant jacket (71) for distributing the coolant is provided on a cylinder block (13) constituting part of the engine body (11), and the outer wall of the cylinder block (13) having the inner surface thereof facing the coolant jacket (71) is formed with an opening (106) which communicates with the coolant jacket (71) and with a mounting portion (107) surrounding an opening (106), in that the exhaust recycling control value (81) including a valve portion (84) having a valve body (88) which can open and close the midsection of the exhaust recycling path (80) and is accommodated in a valve housing (86) and an electrical actuator (85) for driving the valve body (88) connected to the valve portion (84) is mounted to a mounting portion (107) so as to close the opening (106) by the portion of the valve housing (86) on the side of the electrical actuator (85).

Full Text

FORM 2
THE PATENTS ACT 1970
[39 OF 1970]
&
THE PATENTS (AMENDMENT) RULES, 2006
COMPLETE SPECIFICATION
[See Section 10; rule 13]
"ENGINE EXHAUST RECYCLING APPARATUS"
HONDA MOTOR CO., LTD., a corporation of Japan, of 1-1, Minamiaoyama 2-chome, Minato-ku, Tokyo, Japan,
The following specification particularly describes the invention and the manner in which it is to be performed:
[Detailed Description of the Invention]
[0001]

[Technical Field of the Invention]
The present invention relates to an engine exhaust recycling apparatus in which an exhaust recycling control valve is provided in an exhaust recycling path connecting an air

intake system which is connected to an air intake port of an engine body and an exhaust port of the engine body.
[0002]
[Description of the Related Art]
An exhaust recycling apparatus in which an exhaust recycling control valve is provided at the midsection of an exhaust recycling path for recycling part of exhaust passing through an exhaust port of an engine body to the air intake system is already known, for example, in Patent Document 1.
[0003]
[Patent Document 1]
JP-UM-B-61-43969
[0004]
[Problems to be Solved by the Invention]
In the technology described above, the exhaust recycling control valve is mounted to the cylinder block of the engine. However, since the engine is air-cooled type, and in addition, since the exhaust recycling control valve is mounted to the cylinder block in the vicinity of the exhaust port, the temperature of the exhaust recycling control valve increases to a relatively high value, and hence measure for improve the heat-resistance property is required. In addition, in order to improve the efficiency to purify exhaust air, it is desirable to improve controllability of opening by employing an actuator of an electric type for the exhaust recycling control valve.

However, it is difficult to employ the electrical actuator under the circumstance in which the temperature of the exhaust recycling control valve increases to a relatively high value as described above.
[0005]
In view of such circumstances, it is an object of the present invention to provide an engine exhaust recycling apparatus in which the exhaust recycling control valve can be used in the state of being at relatively low temperature.
[0006]
[Means for Solving the Problems]
In order to achieve the object described above, the invention according to Claim 1 is an engine exhaust recycling apparatus in which in which an exhaust recycling control valve is provided in an exhaust recycling path connecting an air intake system which is connected to an air intake port of an engine body and an exhaust port of the engine body, characterized in that the engine body is of a liquid-cooled type configured to be cooled by recycling of a coolant, and the coolant is guided to the exhaust recycling control valve to cool the exhaust recycling control valve.
[0007]
In the arrangement according to Claim 1, since the exhaust recycling control valve can be cooled by coolant and hence the exhaust recycling control valve can be used in a state

of being at relatively low temperature, measure for improving the heat resistant property is not necessary, and the efficiency to purify exhaust air can be improved by improving the opening controllability by employing an actuator of an electric type for the exhaust recycling control valve.
[0008]
In addition to the structure of the invention according to Claim 1, the invention of Claim 2 is characterized in that a coolant jacket for distributing coolant is provided on the engine body, and the exhaust recycling control valve is mounted to an outer wall of the engine body so as to be cooled by the coolant from the coolant jacket. In this arrangement, the exhaust recycling control valve is mounted directly to the engine body while enabling to be used in a state of being at relatively low temperature, so that the entire engine including the exhaust recycling control valve can be configured to a compact structure.
[0009]
In addition to the structure of the invention according to Claim 1, the invention of Claim 3 is characterized in that the exhaust recycling control valve includes a valve portion which can open and close the midsection of the exhaust recycling path and an electrical actuator for driving the valve portion connected to the valve portion, and in that the coolant is guided to the portion of a valve housing provided on the valve

portion on the side of the electrical actuator. In this arrangement, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator.
[0010]
In addition to the structure of the invention according to Claim 1, the invention of Claim 4 is characterized in that the coolant jacket for distributing the coolant is provided on a cylinder block constituting part of the engine body, and the outer wall of the cylinder block having the inner surface thereof facing the coolant jacket is formed with an opening which communicates with the coolant jacket and with a mounting portion surrounding the opening, in that the exhaust recycling control valve including the valve portion having a valve body which can open and close the midsection of the exhaust recycling path and is accommodated in the valve housing and the electrical actuator for driving the valve body connected to the valve portion is mounted to the mounting portion so as to close the opening by the portion of the valve housing on the side of the electrical actuator.
[0011]
In this arrangement of Claim 4, in a state in which the

exhaust recycling control valve is not mouthod, the liquid-cooled jacket of the cylinder block is opened toward the outside via the opening, and thus formation of the liquid-cooled jacket when casing the cylinder block can easily be performed. Furthermore, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator and, in addition, the structure for cooling the exhaust recycling control valve may be simplified to improve its assemblability. [0012]
[Mode for Carrying Out the Invention]
A mode for carrying out the invention will be described based on an embodiment of the present invention shown in the drawings.

[Brief Description of the Drawings]
[Fig. 1] Fig. 1 is a side view of a motorcycle.
[Fig. 2]
Fig. 2 is a side view of a part of an engine.
[Fig. 3]
Fig. 3 is a cross-sectional view taken along the line 3-3 in Fig. 2.
[Fig. 4]
Fig. 4 is a cross-sectional view taken along the line 4-4 in Fig. 3.
[Fig. 5]
Fig. 5 is a cross-sectional view taken along the line 5-5 in Fig. 3.

[0013]
Fig. 1 to Fig. 5 show an embodiment of the present invention. Fig. 1 is a side view of a motorcycle; Fig. 2 is a side view of a part of an engine; Fig, 3 is a cross-sectional view taken along the lien 3-3 in Fig. 2; Fig. 4 is a cross-sectional view taken along the line 4-4 in Fig. 3; and Fig. 5 is a cross-sectional view taken along the line 5-5 in Fig. 3.

[0014]
In Fig. 1, a motorcycle V includes a front wheel WF and a rear wheel WR at the front and the rear of a vehicle body, and the front wheel WF is rotatably supported at the lower end of a front fork 7, which can be rotated leftward and rightward by a steering handle 6. The rear wheel WR is rotatably supported at the rear end of a swing arm 8, which is supported by the vehicle body so as to be capable of swinging upward and downward, and a rear cushion 9 is provided between the swing arm 8 and the vehicle body.
[0015]
Disposed between the front wheel WF and the rear wheel WR is a power unit P which is to be mounted to the vehicle body. The power unit P includes a direct gasoline-injection engine E of four-cycle liquid-cooled type having a cylinder axis C inclined upward and frontward, and a transmission M for changing the speed of the output of the engine E, and the output of the transmission M is transmitted to the rear wheel WR by a chain (not shown).
[0016]
In Fig. 2 to Fig. 4, an engine body 11 of the engine E includes a crankcase 12, a cylinder block 13 to be connected to the crankcase 12, a cylinder head 14 to be connected to the cylinder block 13 on the opposite side from the crankcase 12, and a head cover 15 to be connected to the cylinder head 14

on the side opposite from the cylinder block 13, and is mounted to the motorcycle V with the cylinder head 14 side slightly upward.
[0017]
A piston 17 to be fitted slidably into a cylinder bore 16 provided on the cylinder block 13 is connected to a crankshaft 10 (not shown) rotatably supported by the crankcase 12 via a connecting rod 18 and a crankpin (not shown), and a combustion chamber 19 to which the top of the piston 17 is exposed is defined between the cylinder block 13 and the cylinder head 14.
[0018]
The cylinder head 14 includes a pair of intake valve ports 20.... opening on the ceiling surface of the combustion chamber 19, an air intake port 23 commonly communicated to those intake valve ports 20... and opening on the upper side surface of the cylinder head 14, a single exhaust valve port 22 opening on the ceiling surface of the combustion chamber 19, an exhaust port 24 communicating to the exhaust valve port 22 and opening on the lower side surface of the cylinder head 14, and an injector 25 for directly injecting fuel into the combustion chamber 19 with compressed air disposed on the axis of the cylinder bore 16, that is, on the cylinder axis C.
[0019]
An ignition plug 26 is mounted to the cylinder head 14

so as to be exposed in the combustion chamber 19 at the position other than the intake valve ports 20... and the exhaust valve port 22.
[0020]
The cylinder head 14 includes a pair of openable and closable intake valves 27... which can open and close both of the intake valve ports 20..., and an openable and closable exhaust valve 2 9 which can open and close the exhaust valve port 22.
[0021]
The intake valves 27... are slidably fitted to guide cylinders 30... secured to the cylinder head 14 respectively, and valve springs 32... are provided between retainers 31... and the cylinder head 14, which are fixed respectively to the ends of the intake valves 27. . . projected from the guide cylinders 30.... The intake valves 27... are urged in the valve-closing direction by a spring force exerted by the valve springs 32.... The exhaust valve 29 is slidably fitted into a guide cylinder 33 fixed to the cylinder head 14, and a valve spring 35 is provided between a retainer 34 and the cylinder head 14 which are fixed to the end of the exhaust valve 2 9 projected from the guide cylinder 33. The exhaust valve 29 is urged in the valve-closing direction by a spring force exerted by the valve spring 35.
[0022]

Intake-side and exhaust-side rocker shafts 36, 37 extending in parallel with the axis of the crankshaft are supported by the head cover 15, and an intake-side first rocker arm 38 pivotably supported by the intake-side rocker shaft 36 abuts against the end of the intake valves 27... and an exhaust-side first rocker arm 39 pivotably supported by the exhaust-side rocker shaft 37 abuts against the end of the exhaust valve 29.
[0023]
On the other hand, both ends of a camshaft 41 extending in parallel with the intake-side and exhaust-side rocker shafts 36, 37 are rotatably supported by the cylinder block 13 and a cover 40 secured to the cylinder block 13 via ball bearings 42, 43, and a cam chain 45 for reducing the rotational power from the crankshaft to 1/2 and transmitting the reduced power is wound around a driven sprocket 44 mounted to the camshaft 41 so as not to rotate with respect to each other.
[0024]
An intake-side cam 46 and an exhaust-side cam 47 are fixed to the camshaft 41, and an intake-side second rocker arm (not shown) driven by the intake-side cam 46 and an exhaust-side second rocker arm 49 driven by the exhaust-side cam 47 are pivotably supported by the cylinder block 13. The pivotal movement of the intake-side second rocker arm is transmitted to the intake-side first rocker arm 38 via an intake-side push

rod 50, and the pivotal movement of the exhaust-side second rocker arm 49 is transmitted to the exhaust-side first rocker arm 39 via an exhaust-side push rod 51.
[0025]
The injector 25 is supplied with compressed air from a compressed air pump 54 having an operational axis extending in parallel with the cylinder axis C of the engine body 11 and being mounted to the lower side wall of the cylinder block 13, and a power is transmitted from the camshaft 41 to the compressed air pump 54.
[0026]
In other words, a drive sprocket 55 is integrally formed with the driven sprocket 44 mounted to the camshaft 41 so as not to rotate with respect to each other, and a power is transmitted to the compressed air pump 54 via an endless chain 56 wound around the drive sprocket 55. In this manner, the compressed air pump 54 is of a reciprocating type having the operational axis extending in parallel with the cylinder axis C, and a rotational power transmitted from the chain 56 is converted into a reciprocating motion of the compressed air pump 54 via a crank mechanism, not shown.
[0027]
The injector 25 includes an air-fuel injection valve 58 having a nozzle 57 which projects into the combustion chamber 19 and is mounted to the cylinder head 14, and a fuel injection

valve 59 connected to the air-fuel injection valve 58 so as to inject fuel from behind into the air-fuel injection valve 58. The air-fuel injection valve 58 injects fuel together with compressed air directly into the combustion chamber 19.
[0028]
The cylinder head 14 includes a fitting hole 60, to which the nozzle 57 is hermetically fitted, and an insertion cylinder 61 having an inner diameter larger than the fitting hole 60 and continuing coaxially to the fitting hole 60, both provided coaxially with the cylinder axis C. The air-fuel injection valve 58 is inserted into the insertion cylinder 61 until the nozzle 57 is fitted hermetically into the fitting hole 60 and abuts against an annular shoulder 62 formed between the fitting hole 60 and the insertion cylinder 61 with the intermediary of a wave spring washier 63.
[0029]
On the other hand, the head cover 15 is formed integrally with a cylindrical injector housing 64 which fits on and holds the fuel injection valve 59 and clamps the air-fuel injection valve 58 with respect to the cylinder head 14, so that the extremity of the injector housing 64 abuts against the rear end of the air-fuel injection valve 58 when combining the head cover 15 to the cylinder head 14. A clamping plate 65 for clamping the rear end of the fuel injection valve 59 with respect to the injector housing 64 is secured to the rear end

of the injector housing 64.
[0030]
An annular fuel chamber 66 communicating with the interior of the fuel injection valve 59 is defined between the injector housing 64 and the fuel injection valve 59, and a pair of sealing members 67, 68 for clamping the fuel chamber 66 from both sides are interposed between the fuel injection valve 59 and the injector housing 64, In addition, the head cover 15 is formed with a fuel supply path 69 communicating with the fuel chamber 66, and fuel which is adjusted to a constant pressure is supplied to the fuel chamber 66 via the fuel supply path 69.
[0031]
An annular air chamber 70 communicating with the interior of the air-fuel injection valve 58 is defined between the distal end of the fuel injection valve 59 and the rear end of the air-fuel injection valve 58 and the injector housing 64. Compressed air from the compressed air pump 54 is supplied to the air chamber 70.
[0032]
The engine body 11 is of a liquid-cooled type configured to be cooled by recycling of coolant. Coolant jackets 71, 72 for distributing coolant are provided respectively on the cylinder block 13 and the cylinder head 14 of the engine body 11. An air intake system 74 including an air intake pipe 73

is connected to the air intake port 23 of the cylinder head 14, and the downstream end of an exhaust pipe 75 connected to the exhaust port 24 of the cylinder head 14 is connected to an exhaust muffler 76 to be disposed on the right side of the rear wheel WR.
[0033]
Part of exhaust passing through the exhaust port 24 is to be recycled toward the air intake system 74 via an exhaust recycling path 80, and an exhaust recycling control valve 81 is disposed at the midsection of the exhaust recycling path 80.
[0034]
An upper recycling path 80a of the exhaust recycling path 80 located between the exhaust recycling control valve 81 and the exhaust port 24 is defined within an upstream duct line 82 provided between the cylinder head 14 and the exhaust recycling control valve 81, and a downstream duct line 80b of the exhaust recycling path 80 located between the exhaust recycling control valve 81 and the air intake system 74 is defined within a downstream duct line 83 provided between the air intake pipe 73 in the air intake system 74 and the exhaust recycling control valve 81.
[0035]
Referring also to Fig. 5, the exhaust recycling control valve 81 includes a valve portion 84 which can open and close

the midsection of the exhaust recycling path 80 and an electrical actuator 85 for driving the valve portion 84 connected thereto, and coolant passing through the coolant jackets 71, 72 provided on the engine body 11, in particular, coolant passing through the coolant jacket 71 of the cylinder block 13 of the engine body 11 is guided to the exhaust recycling control valve 81 mounted to the cylinder block 13 so as to cool the exhaust recycling control valve 81.
[0036]
The valve portion 84 of the exhaust recycling control valve 81 includes a valve housing 86, a valve seat member 87 to be fixed within the valve housing 86, a valve body 88 which can get seated on the valve seat member 87, and a return spring 89 for exerting a spring force to make the valve body 88 seated on the valve seat member 87.
[0037]
The valve housing 86 is formed into a shouldered cylindrical shape having a bulkhead portion 86a at the midsection in the axial direction. An opening at one end in the axial direction is closed in a liquid-tight manner by screwing a lid member 90 into the valve housing 86. The valve seat member 87 is fixed to the valve housing 86 so as to be interposed between a shoulder 86b provided on the inner surface of the valve housing 86 between the bulkhead portion 86a and the lid member 90 and exposing toward the lid member 90 and

a stop ring 91 mounted to the inner surface of the valve housing
86 and engaged with the outer periphery of the valve seat member
87 at one end. In addition, an upstream valve chamber 92 is defined in the valve housing 86 between the valve seat member 87 and the lid member 90, and a downstream valve chamber 93 is formed between the valve seat member 87 and the bulkhead portion 86a.
[0038]
The valve body 88 can block between the upstream and the downstream valve chambers 92, 93 by getting seated at the center of the valve seat member 87 in the upstream valve chamber 92, and is provided integrally at one end of a valve shaft 94 loosely passing through the center of the valve seat member 87. The valve shaft 94 passes through the bulkhead portion 86a so as to be capable of moving in the axial direction, and a cylindrical guiding member 95 being in sliding contact with the outer periphery of the valve shaft 94 is mouthed to the bulkhead portion 86a so as to guide the movement of the valve shaft 94 and preventing leakage of gas from the downstream valve chamber 93.
[0039]
A retainer 96 is mounted to the valve shaft 94 at the other end, and the return spring 89 is disposed between a spring receiving seat 97 received by the bulkhead portion 86a and the retainer 96 in a contracted state.

[0040]
The electrical actuator 85 is configured to actuate a drive shaft 98 which abuts coaxially against the other end of the valve shaft 94 in the axial direction, for example, by an output of a step motor, and a housing 99 of the electrical actuator 85 is connected to the other end of the valve housing 86 so as to define a spring chamber 100 for accommodating the return spring 89 with respect to the bulkhead chamber 86a.
[0041]
In this manner, the amount of passage of exhaust air between the upstream valve chamber 92 and the downstream valve chamber 93 is controlled by driving the valve shaft 94 in the axial direction against a spring force of the return spring 89 by the operation of the electrical actuator 85.
[0042]
The upstream end of the upstream duct line 82 defining the upstream recycling path 80a of the exhaust recycling path 80 is inserted into the cylinder head 14 so as to be communicated with the exhaust port 24 with the intermediary of an annular sealing member 101 with respect to the cylinder head 14, and the sealing member 101 is tightly clamped and thus seals between the upstream duct line 82 and the cylinder head 14 by screwing and tightening a cylindrical holding member 102 surrounding the upstream end of the upstream duct line 82 into the cylinder head 14. Accordingly, the upstream end of the upstream duct

line 82 can be slid in the axial direction, and is connected hermetically to the cylinder head 14.
[0043]
The downstream end of the upstream duct line 82 is screwed into the valve housing 86 of the exhaust recycling control valve 81 so as to communicate the downstream end of the upstream recycling path 80a with the upstream valve chamber 92, and an annular sealing member 103 is interposed between the valve housing 86 and the upstream duct line 82.
[0044]
The downstream duct line 83 defining the downstream recycling path 80b of the exhaust recycling path 80 is provided with a flange 83a at the upstream end thereof, and the flange 83a is secured to the valve housing 86 by a pair of bolts 104, 104 so as to communicate the upstream end of the downstream recycling path 80b with the downstream valve chamber 93. The downstream duct line 83 is provided with a flange 83b at the downstream end, and the downstream end of the downstream recycling path 80b is brought into communication with the interior of the air intake pipe 73 by the flange 83b being secured to the air intake pipe 73 of the air intake system 74 with a plurality of bolts 105....
[0045]
The outer wall of the cylinder block 13, facing the coolant jacket 71 at the inner surface thereof, is formed with

an opening 106 which communicates with the coolant jacket 71, and is provided with a mounting portion 107 surrounding the opening 106. The exhaust recycling control valve 81 is mounted to the mounting portion 107 with a plurality, for example, a pair of bolts 108, 108 so as to close the opening 106 by the portion of the valve housing 86 on the side of the electrical actuator 85.
[0046]
In other words, a flange 110 corresponding to the mounting portion 107 is integrally formed on the portion of the valve housing 86 corresponding to the spring chamber 100, and the flange 110 including a gasket 109 interposed with respect to the mounting portion 107 is secured to the mounting portion 107 with the bolts 108, 108. Accordingly, the valve housing 86, or the exhaust recycling control valve 81 is mounted to the cylinder block 13 so as to close the opening 106 by the flange 110 of the valve housing 86.
[0047]
In addition, the flange 110 is formed with an opening hole 111 communicating with the spring chamber 100 and a groove 112 defining a passage between the opening hole 111 and the gasket 109 for opening the opening hole 111 toward the outside.
[0048]
Subsequently, the operation of this embodiment will be described. Since coolant is guided to the exhaust recycling

control valve 81 provided in the exhaust recycling path 80 connecting the air intake pipe 73 of the air intake system 74 connected to the air intake port 23 of the engine body 11 of a liquid-cooled type configured to be cooled by recycling of coolant and exhaust port 24 of the engine body 11, and thus the exhaust recycling control valve 81 can be cooled by coolant/ the exhaust recycling control valve 81 can be used in a state of being at a relatively low temperature. Therefore, measure for improving the heat resistant property is not necessary, and the efficiency of purifying exhaust air may be improved by enhancing controllability of opening by employing the actuator 85 of an electric type for the exhaust recycling control valve 81.
[0049]
In addition, since the exhaust recycling control valve 81 is mounted to an outer wall of the cylinder block 13 so as to be cooled by the coolant from the coolant jacket 71 provided on the cylinder block 13 of the engine body 11, the exhaust recycling control valve 81 is mounted directly to the cylinder block 13 of the engine body 11 while enabling to be used in a state of being at relatively low temperature, so that the entire engine E including the exhaust recycling control valve 81 can be configured to a compact structure.
[0050]
Since the exhaust recycling control valve 81 includes

the valve portion 84 which can open and close the midsection of the exhaust recycling path 80 and the electrical actuator 85 for driving the valve portion 84 connected to the valve portion 84, and the coolant from the coolant jacket 71 is guided to the portion of the valve housing 86 provided on the valve portion 84 on the side of the electrical actuator 85, the valve portion 84 of the exhaust recycling control valve 81 is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion 84 to the electrical actuator 85 is effectively held down to control increase in temperature of the electrical actuator 85.
[0051]
The outer wall of the cylinder block 13 having the inner surface facing the coolant jacket 71 is formed with the opening 106 which communicates with the coolant jacket 71 and with the mounting portion 107 surrounding the opening 106, and the exhaust recycling control valve 81 is mounted to the mounting portion 107 so that the opening 106 is closed by the portion of the valve housing 86 provided on the valve portion 84 on the side of the electrical actuator 85.
[0052]
In other words, in a state in which the exhaust recycling control valve; 81 is not mouthed, the liquid-cooled jacket 71 of the cylinder block 13 is opened toward the outside via the

opening 106, and thus formation of the liquid-cooled jacket 71 when casing the cylinder block 13 can easily be performed.
[0053]
In addition, the structure for cooling the exhaust recycling control valve 81 may be simplified to improve its assemblability.
[0054]
Although the embodiment of the present invention has been described thus far, the present invention is not limited thereto, and various modifications in design may be performed without departing from the scope of the present invention stated in appended Claims.
[0055]
[Advantages of the Invention]
As described above, according to Claim 1, since the exhaust recycling control valve can be cooled by coolant and hence the exhaust recycling control valve can be used in a state of being at relatively low temperature, measure for improving the heat resistant property is not necessary, and the efficiency to purify exhaust air can be improved by improving the opening controllability by employing an actuator of an electric type for the exhaust recycling control valve.
[0056]
According to the invention of Claim 2, the exhaust recycling control valve is mounted directly to the engine body

while enabling to be used in a state of being at relatively low temperature, so that the entire engine including the exhaust recycling control valve can be configured to a compact structure.
[0057]
According to the invention of Claim 3, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator.
[0058] According to the invention of Claim 4, formation of the liquid-cooled jacket when casing the cylinder block can easily be performed. Furthermore, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator ef f ectiyely and, in addition, the structure for cooling the exhaust recycling control valve may be simplified to, improve its assemblability.

[Reference Numerals] 11...engine body 23...air intake port 24...exhaust port 71, 72...coolant jacket 74...air intake system 80...exhaust recycling path 81...exhaust recycling control valve 84...valve portion 85...electrical actuator 86...valve housing 88...valve body

106...opening
107...mounting portion
E...engine
The present invention relates to an engine exhaust recycling apparatus
[0001]
[Technical Field of the Invention]
The present invention relates to an engine exhaust recycling apparatus in which an exhaust recycling control valve is provided in an exhaust recycling path connecting an air

However,it is difficult to employ the electrical actuator under the circumstance in which the temperature of the exhaust recycling control valve increases to a relatively high value as described above.
[0005]
In view of such circumstances, it is an object of the present invention to provide an engine exhaust recycling apparatus in which the exhaust recycling control valve can be used in the state of being at relatively low temperature.
[0006]
[Means for Solving the Problems]
In order to achieve the object described above, the invention according to first aspect is an engine exhaust recycling
apparatus in which in which an exhaust recycling control valve is provided in an exhaust recycling path connecting an air intake system which is connected to an air intake port of an engine body and an exhaust port of the engine body, characterized in that the engine body is of a liquid-cooled type configured to be cooled by recycling of a coolant, and the coolant is guided to the exhaust recycling control valve to cool the exhaust recycling control valve. [0007] In the arrangement according to first aspect since the exhaust recycling control valve can be cooled by coolant and hence the exhaust recycling control valve can be used in a state

of being at relatively low temperature, measure for improving the heat resistant property is not necessary, and the efficiency to purify exhaust air can be improved by improving the opening controllability by employing an actuator of an electric type for the exhaust recycling control valve.
[0008J
In .addition to the structure of the invention according :o first aspect the invention of another aspect is characterized in that a coolant jacket for distributing coolant is provided on the. engine body, and the exhaust recycling control valve is mounted to an outer wall of the engine body so as to be cooled by the coolant from the coolant jacket. in this arrangement, the exhaust recycling control valve is mounted directly to the engine body while enabling to be used in a state of being at relatively low temperature, so that the entire engine including the exhaust recycling control valve can be configured to a compact structure.
[0009]
In addition to the. structure of the invention according to first aspect, the invention of another aspect is characterized in that
the exhaust recycling control valve includes a valve portion which can open and close the midsection of the exhaust recycling path and an electrical actuator for driving the valve portion
connected to the valve portion, and in that the coolant is guided to the portion of a valve housing provided on the valve

portion on the side of the electrical actuator. In this
arrangement, the valve portion of the exhaust recycling control
valve is prevented from excessively decreasing in temperature
to maintain activation of recycling exhaust air, while heat
transmission from the valve portion to the electrical actuator
is effectively held down to control increase in temperature
of the electrical actuator.
[0010]
In addition to the structure of the invention according to first aspect, the invention of another aspect is characterized in thai
the coolant jacket for distributing the coolant is provided
on a cylinder block constituting part of the engine body, and
the outer wall of the cylinder block having the inner surface
thereof facing the coolant jacket is formed with an opening
which communicates with the coolant jacket and with a mounting
portion surrounding the opening, in that the exhaust recycling
control valve including the valve portion having a valve body
which can open and close the midsection of the exhaust recycling
path and is accommodated in the valve housing and the electrical
actuator for driving the valve body connected to the valve
portion is mounted to the mounting portion so as to close the
opening by the portion of the valve housing on the side of the
electrical actuator.
[0011]
In this arrangement of another aspect, in a state in which the

opening 106, and thus formation of the liquid-cooled jacket 71 when casing the cylinder block 13 can easily be performed. [0053]
In addition, the structure for cooling the exhaust recycling control valve 81 may be simplified to improve its assemblability. [0054]
Although the embodiment of the present invention has been described thus far, the present invention is not limited thereto, and various modifications in design may be performed without departing from the scope of the present invention stated in appended Claims. [0055]
[Advantages of the Invention] As described above, according to first ' aspect, since the exhaust recycling control valve can be cooled by coolant and hence the exhaust recycling control valve can be used in a state of being at relatively low temperature, measure for improving the heat resistant property is not necessary, and the efficiency to purify exhaust air can be improved by improving the opening controllability by employing an actuator of an electric type for the exhaust recycling control valve.
[0056]
According to the invention of another aspect, the exhaust
recycling control valve is mounted directly to the engine body

While enabling to be used in a state of being at relatively low temperaturer so that the entire engine including the exhaust recycling control valve can be configured to a compact structure..
[0057] According to the invention of another aspect, the Valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is"effectively held down to control increase in temperature of the electrical actuator.
[0058]
According to the invention of another aspect, formation of the
liquid-cooled jacket when casing the cylinder block can easily be performed. Furthermore, the valve portion of the exhaust recycling control valve is prevented from excessively decreasing in temperature to maintain activation of recycling exhaust air, while heat transmission from the valve portion to the electrical actuator is effectively held down to control increase in temperature of the electrical actuator effectively and, in addition, the structure for cooling the exhaust recycling control valve may be -simplified to improve its assemblability.

WE CLAIM:
1. An engine exhaust recycling apparatus for a liquid-cooled type engine including an engine body (11) having an air intake port (23), an exhaust port (24) and coolant gaskets (71, 72) through which coolant passes through being provided thereto, said engine exhaust recycling apparatus comprising an exhaust recycling path (80) connected to the air intake part (23) and exhaust port (24) of said engine body (11), characterized in that said exhaust recycling path (80) is provided with an exhaust recycling control valve (81) mounted to said engine body such that the coolant is guided through said coolant jackets (71, 72) to cool said exhaust recycling control valve (81).
2. An engine exhaust recycling apparatus as claimed in claim 1, wherein said exhaust recycling control valve is mounted to the outer wall of said engine body so as to be cooled by the coolant from the coolant gaskets.
3. An engine exhaust apparatus as claimed in claim 1, wherein said exhaust recycling control valve (81) includes a valve portion (84) provided at the midsection of said exhaust recycling path (80), an electrical actuator (85) driving said valve portion (84), and a valve housing (86) provided on the valve portion (84) along the side of said electrical actuator (85) where said coolant is guided through said coolant jackets (71, 72).
4. An engine exhaust recycling apparatus as claimed in claim 1, wherein the coolant
jacket (71) for distributing the coolant is provided on a cylinder block (13) constituting part of the
engine body (11), and the outer wall of the cylinder block (13) having the inner surface thereof facing
the coolant jacket (71) is formed with an opening (106) which communicates with the coolant jacket
(71) and with a mounting portion (107) surrounding an opening (106), in that the exhaust recycling
control value (81) including a valve portion (84) having a valve body (88) which can open and close
the midsection of the exhaust recycling path (80) and is accommodated in a valve housing (86) and

an electrical actuator (85) for driving the valve body (88) connected to the valve portion (84) is mounted to a mounting portion (107) so as to close the opening (106) by the portion of the valve housing (86) on the side of the electrical actuator (85).

Documents:

153-mum-2004-abstract(11-2-2004).pdf

153-MUM-2004-ABSTRACT(11-6-2012).pdf

153-MUM-2004-ABSTRACT(11-8-2014).pdf

153-mum-2004-claims(11-2-2004).pdf

153-MUM-2004-CLAIMS(AMENDED)-(11-6-2012).pdf

153-MUM-2004-Claims-251114.pdf

153-MUM-2004-CORRESPONDENCE(12-5-2009).pdf

153-mum-2004-correspondence(29-1-2008).pdf

153-MUM-2004-CORRESPONDENCE(3-7-2014).pdf

153-MUM-2004-DECLARATION(11-8-2014).pdf

153-mum-2004-description(complete)-(11-2-2004).pdf

153-mum-2004-drawing(11-2-2004).pdf

153-MUM-2004-DRAWING(11-6-2012).pdf

153-MUM-2004-ENGLISH TRANSLATION(11-8-2014).pdf

153-MUM-2004-ENGLISH TRANSLATION(17-10-2014).pdf

153-mum-2004-form 1(11-2-2004).pdf

153-MUM-2004-FORM 1(11-6-2012).pdf

153-MUM-2004-FORM 1(11-8-2014).pdf

153-MUM-2004-FORM 1(17-10-2014).pdf

153-MUM-2004-FORM 13(11-6-2012).pdf

153-mum-2004-form 13(12-5-2009).pdf

153-mum-2004-form 13(29-1-2008).pdf

153-mum-2004-form 18(29-1-2008).pdf

153-mum-2004-form 2(11-2-2004).pdf

153-mum-2004-form 2(title page)-(11-2-2004).pdf

153-MUM-2004-FORM 2(TITLE PAGE)-(11-6-2012).pdf

153-MUM-2004-FORM 2(TITLE PAGE)-(11-8-2014).pdf

153-mum-2004-form 3(11-2-2004).pdf

153-MUM-2004-FORM 3(11-6-2012).pdf

153-mum-2004-form 5(11-2-2004).pdf

153-MUM-2004-FORM 5(11-8-2014).pdf

153-MUM-2004-MARKED COPY(11-8-2014).pdf

153-MUM-2004-OTHER DOCUMENT(17-10-2014).pdf

153-MUM-2004-OTHERS-251114.pdf

153-MUM-2004-PETITION UNDER RULE 137(11-6-2012).pdf

153-MUM-2004-POWER OF ATTORNEY(3-7-2014).pdf

153-MUM-2004-POWER OF AUTHORITY(11-6-2012).pdf

153-mum-2004-power of authority(21-6-2004).pdf

153-MUM-2004-REPLY TO EXAMINATION REPORT(11-6-2012).pdf

153-MUM-2004-REPLY TO EXAMINATION REPORT(23-5-2012).pdf

153-MUM-2004-REPLY TO HEARING(11-8-2014).pdf

153-MUM-2004-REPLY TO HEARING(17-10-2014).pdf

153-MUM-2004-SPECIFICATION(AMENDED)-(11-6-2012).pdf

153-MUM-2004-SPECIFICATION(AMENDED)-(11-8-2014).pdf

153-MUM-2004-SPECIFICATION(MARKED COPY)-(11-6-2012).pdf

153-MUM-2004-URDIP SEARCH REPORT(31-12-2010).pdf

Petition under rule 137 [153-MUM-2004].pdf

Specimen Form 1_as amended.pdf

Specimen Form 1_as marked.pdf

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Patent Number

263971

Indian Patent Application Number

153/MUM/2004

PG Journal Number

49/2014

Publication Date

05-Dec-2014

Grant Date

28-Nov-2014

Date of Filing

11-Feb-2004

Name of Patentee

HONDA MOTOR CO. LTD

Applicant Address

1-1 MINAMIAOYAMA 2-CHOME, MINATO-KU, TOKYO

Inventors:

#	Inventor's Name	Inventor's Address
1	KAORU HANAWA	C/o. Kabushiki Kaisha Honda Gjiutsu Kenkyusho, 4-1 Chuo 1-chome, Wako-shi, Saitama

PCT International Classification Number

F02M25/06

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	2003-052985	2003-02-28	Japan