Title of Invention

AN INTERNAL COMBUSTION ENGINE

Abstract

AN INTERNAL COMBUSTION ENGINE This invention relates to an internal combustion engine having an integrated design of coolant pump and oil pump. An integrated approach is devised for housing the coolant pump and oil pump elements together in the crankcase cover. The impeller (12) of the coolant pump is mounted directly on the front end of the balancer shaft (13), which runs parallel to the crankshaft at the same speed but in opposite direction. The construction of the engine crankcase (3) is simplified due to elimination of the volute cavity (12a) required for coolant pump. This cavity is incorporated in the crankcase cover in this system. The timing drive is simplified by elimination of the coolant pump thereby reducing the timing belt length and increasing the life. Fig. 2

Full Text

FORM 2 THE PATENTS ACT 1970 (39 of 1970) & THE PATENTS RULES, 2003 COMPLETE SPECIFICATION (See Section 10; rule 13) TITLE OF THE INVENTION AN INTERNAL COMBUSTION ENGINE APPLICANTS TATA MOTORS LIMITED, an Indian company having its registered office at Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001 Maharashtra, India INVENTORS Narendra Kumar Jain, Hemant Ambadas Malekar and Kedar Digambar Gokhale all Indian national of TATA MOTORS LIMITED an Indian company having its registered office at Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001 Maharashtra, India PREAMBLE TO THE DESCRIPTION The following Complete specification particularly describes the invention and the manner in which it is to be performed. FIELD OF THE INVENTION: This invention relates to an Internal Combustion (IC) engine, which is developed with an integrated design approach for improved drive system for the coolant pump. The system according to this invention is compact, reduces the number of parts and its complexity. Consequently, the invented engine is cost effective in comparison with the existing complex systems. BACKGROUND OF THE INVENTION: In conventional IC engine, lubrication of rotating parts is ensured by oil pump. Major components like cylinder head, cylinder crank case and the like are cooled by pressurized supply of coolant by coolant pump. The oil pump is driven by the crank shaft and is housed in the front cover of the cylinder block. The coolant pump is mounted on the front face of the cylinder block and is driven separately by drive means such as belt, chain, gear and timing belt drives. The coolant pump cavity is cast in the cylinder block. This complicates the casting process and affects the accuracy of the pumping process or performance. In this arrangement or system, the coolant pump element or the impeller need support bearings. Conventionally, a double row ball bearings or integrated shaft bearings are used. A separate drive means such as drive pulleys, chain and sprocket means, or gear arrangement is required for driving the coolant pump. This coolant pump provided with drive means increases the complexity of construction and hence the cost. PRIOR ART The publication number US2001/ 0023668A1 dated September 27, 2001 discloses an integrated front module housing comprising of thermostat housing, water pump housing, oil pump housing, coolant and oil passages, support boss member and sensor housing. The method of manufacture of this integral casting is also disclosed. The invention is for the integration concept of various housings and its manufacturing method. It does not -2- have any additional balancer shaft parallel to the crankshaft. The water pump housing is integral with the front cover for the conventional water pump design. The US Patent publication number 5704329 dated January 6, 1998 discloses a front cover, which is mounted on the front end of an IC engine to cover cam gear drive mechanism. The mounting of various accessories is provided on this cover. However it does not have coolant pump. OBJECTS OF THE INVENTION: The main object of this invention is to develop an internal combustion engine using an integrated design approach for the coolant pump and oil pump by adopting an innovative drive system for the coolant pump, which is compact, simple and cost effective with higher reliability and efficacy. BRIEF DESCRIPTION OF THIS INVENTION This invention relates to an internal combustion engine having integrated coolant pump and oil pump and which comprises of a balancer shaft drivable by a crank shaft through a drive means for rotating the crank shaft and the balancer shaft in the same speed but in the opposite direction, said balancer shaft being adjacent to said crank shaft, the front end of said balancer shaft is extended for driving the impeller of said coolant pump, the coolant pump volute cavity formed in the cover for the cylinder crankcase of the said engine. The timing drive of the engine is simplified due to elimination of the coolant pump from the drive. The timing drive means is located on the front end of said crankshaft to drive the camshaft alone. Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting the same, -3- this invention will now be described in detail with reference to the figures 1 to 5 in the accompanying drawings. Fig 1 shows the front view of the IC engine of this invention wherein reference numerals 1,2,3 , 4, 5, 6, 7 and 8 represent the following respectively. 1. Crank case cover 2. Gasket for crank case cover 3. Crank case 4. Pressurized oil supply channel 5. Main oil gallery 6. Coolant supply channel for crank case 7. Coolant inlet for crank case 8. Bypass hose Fig 2 is a sectional view of the position marked A - A in Fig 1. Reference numerals 9 to 16 are as described hereinafter. 9. The coolant pump cover 10. The coolant suction from the radiator 11. Coolant bypass connection 12. The impeller 12a. The coolant pump volute cavity 13. The balancer shaft 14. The coolant seal 15. The oil seal for the coolant pump 16. Driving gear for the balancer shaft Fig 3 is the sectional view of B - B shown in Fig 1. Reference numeral 17 shows the driving gear for the balancer shaft, 18 is the crankshaft and 19 is the oil seal for the oil pump. -4- Fig 4 is the integrated crank case cover where other reference numerals are as herein described. Numeral 20 is the sensor mounting lug, 21 is the oil pressure relief valve housing and 22 the bypass nipple. Fig 5 is the rear view of the integrated crank case cover, wherein 23 stands for the dowel mounting holes, 24 the mounting holes and 25 the oil pump elements. DESCRIPTION RELATING TO THE EMBODIMENTS AND THE METHOD OF OPERATION Primary inertia forces induced by the reciprocating mass of the engine are balanced by the balancer shaft (13) which is driven by the crank shaft (18). Driving means may be selected from chain / belt or gears (16 & 17). The drive means rotate the shafts in the same speed but in the opposite direction. The crank case (3) skirt portion is extended to accommodate the balancer shaft (13), which is positioned adjacent to the crank shaft (18). Two Hydrodynamic bearings support the balancer shaft. The impeller (12) of the coolant pump is driven by the front end of the balancer shaft (13) which is extended thereto. The impeller (12) can also be mounted on separate shaft called "Impeller shaft" housed in the coolant pump and that can be driven by front end of the balancer shaft (13). In such case oil seal (15) can be replaced by a ball bearing, which apart from supporting the impeller shaft will also seal the crankcase (3). The cover (1) of the crank case (3) is integrated with housing of the coolant pump. The crankcase cover (1) also holds an oil pump, the element (25) of which is driven by the front end of the crank shaft (18). With this arrangement, the coolant pump volute cavity (12a) becomes a part of the crankcase cover (1). Thus the crankcase cover (1) houses the oil pump, the oil suction port, the pressurized oil supply channel (4) to main oil gallery (5), the oil pressure relief valve circuit (21), coolant pump, the coolant suction, the channel for coolant supply (6) to coolant inlet (7) to crankcase (3), and the coolant bypass connection (11). The oils seals (15 & 19) are pre-assembled in the crankcase cover (1). The coolant seal (14) is assembled on balancer shaft (13) using suitable tools / fixture to ensure its desired -5- working height / clearances. The space between the oil seal (15) and coolant seal (14) collects the seepage coolant, which is connected to a cosmetic drain port, designed to carry this liquid coolant away. The impeller (12) is assembled on the front end of the balancer shaft (13) and is covered by the coolant pump cover (9), which is also functioning as coolant suction port (10). The radiator outlet hose fits on the coolant pump cover (9) to provide an axial entry for the coolant in the coolant pump. The coolant bypass hose (8) from the crankcase (3) is connected to the bypass nipple (22) on the coolant pump cover (9). This coolant bypass channel can also be incorporated in the crankcase cover (1). This forms an integral assembly of coolant pump, oil pump and crankcase cover (1). The crankcase cover (1) can be manufactured either by High Pressure Die Casting (HPDC), or Gravity Die Casting (GDC), or Low Pressure Die Casting (LPDC), or by Fabrication method. In addition, the crank speed sensor mounting lug (20) is provided on the crankcase cover (1). The mounting of the crankcase cover (1) on the crankcase (3) is facilitated through multiple mounting holes (24) for M6 screws with two dowel mounting holes (23) for ensuring required alignment and gasket (2) seals the joint between crankcase cover (1) and the crankcase (3). The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purpose of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof. WE CLAIM J) An internal combustion engine having an integrated coolant pump and oil pump, which comprises of a balancer shaft driven by a crank shaft through drive means for rotating both the shafts with the same speed but in the opposite directions, said balancer shaft being adjacent to said crank shaft, a coolant pump and an oil pump drivable by said balancer shaft and the crankshaft respectively, the front end of said balancer shaft is extended for driving the impeller of said coolant pump, the volute cavity of said coolant pump is formed in the cover for the cylinder crankcase of the said engine. 2) The engine as claimed in claim 1, wherein said drive means is either gear drive, chain drive or belt drive. 3) The engine as claimed in claims 1 and 2, wherein the impeller of the said coolant pump is mountable on a separate impeller shaft and is driven directly by the front end of the said balancer shaft. 4) The engine as claimed in claims 1 to 3, wherein the coolant bypass channel is incorporated in the crankcase cover casting. 5) The engine as claimed in claims 1 to 4, wherein mounting means are provided within said crankcase cover for mounting sensors and accessories like hose and cables. 6) The engine as claimed in claim 1 wherein the said cover of the cylinder crankcase is manufactured either by High Pressure Die Casting (HPDC), or Gravity Die Casting (GDC), or Low Pressure Die Casting (LPDC), or by Fabrication method. -7- 7) The engine as claimed in any one of the claims 1 to 6, wherein the coolant bypass from the crankcase is connected to the bypass nipple on the coolant pump cover. 8) The engine as claimed in any one of the above said claims, wherein the timing drive means is located on front end of the said crankshaft to drive the camshaft alone. 9) The engine as claimed in claims 1 and/or 3 wherein the oil seal or a ball bearing is placed on front end of the balancer shaft or on impeller shaft to seal the crankcase. 10) The Internal Combustion Engine substantially as herein described with reference to Fig. 1 to 5 of the accompanying drawings. Dated this 28th day of December 2006. TATA MOTORS LIMITED By their Agent & Attorney (JL LL^ck^ (Karuna Goleria) of DePENNING & DePENNING -8- ABSTRACT AN INTERNAL COMBUSTION ENGINE This invention relates to an internal combustion engine having an integrated design of coolant pump and oil pump. An integrated approach is devised for housing the coolant pump and oil pump elements together in the crankcase cover. The impeller (12) of the coolant pump is mounted directly on the front end of the balancer shaft (13), which runs parallel to the crankshaft at the same speed but in opposite direction. The construction of the engine crankcase (3) is simplified due to elimination of the volute cavity (12a) required for coolant pump. This cavity is incorporated in the crankcase cover in this system. The timing drive is simplified by elimination of the coolant pump thereby reducing the timing belt length and increasing the life. Fig. 2

Documents:

2152-mum-2006- claim.doc

2152-mum-2006-abstract(28-12-2006).pdf

2152-mum-2006-abstract-1.jpg

2152-mum-2006-abstract.doc

2152-mum-2006-abstract.pdf

2152-mum-2006-claims(granted)(28-12-2006).pdf

2152-mum-2006-claims.pdf

2152-mum-2006-correspondance-received.pdf

2152-mum-2006-correspondence(13-06-2007).pdf

2152-mum-2006-correspondence(ipo)-(11-04-2007).pdf

2152-mum-2006-description (complete).pdf

2152-mum-2006-drawing(28-22-2006).pdf

2152-mum-2006-drawings.pdf

2152-mum-2006-form 1(28-12-2006).pdf

2152-mum-2006-form 18(02-01-2007).pdf

2152-mum-2006-form 2(granted)-(28-12-2006).pdf

2152-mum-2006-form 3(28-12-2006).pdf

2152-mum-2006-form 5(28-12-2006).pdf

2152-mum-2006-form 8(13-06-2007).pdf

2152-mum-2006-form 9(02-01-2007).pdf

2152-mum-2006-form-1.pdf

2152-mum-2006-form-2.doc

2152-mum-2006-form-2.pdf

2152-mum-2006-form-26.pdf

2152-mum-2006-form-3.pdf

2152-mum-2006-form-5.pdf

2152-mum-2006-power of attorney(17-09-2004).pdf

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