Title of Invention

"A RICE TRANSPLANTER"

Abstract

An intermediate boss 160, or a rolling feearing member of a transplanting portion 15, is so mounted on a transverse frame 45, or a transplanting frame 20 in a direction perpendicular to the intermediate boss 160 that at least a part of the intermediate boss 160 overlaps with the transverse frame 45 in a plan view. Therefore, even if a hitch bed 161 or a connecting merrtaer for connecting the intermediate boss 160 and the transverse frame 45 becomes necessary, a lighter and less expensive hitch bed 161 than those of the prior art can be used because this hitch bed 161 is reduced in size and a moment acting on the bed is reduced, thus realizing reduction of the weight and cost of the riding rice transplanter.

Full Text

Field of the Invention This invention relates to a riding rice transplanter comprising a vehicle and a transplanting portion. Background Art A transplanting portion of a riding rice transplanter is so mounted that it can be kept horizontal by a rolling control mechanism even if the vehicle tilts laterally. The rolling control mechanism connects the transplanting portion to the vehicle so that the transplanting portion can be laterally tilted around a longitudinally arranged (in a traveling direction) rolling fulcrum shaft, thereby controlling an actuator for tilting the transplanting portion laterally so that the value of a sensor for detecting the tilt of the transplanting portion will be the value obtained when the transplanting portion is horizontal without being laterally tilted. In addition, there was a mechanism that can elastically keep horizontal a transplanting portion connected to a vehicle so that the transplanting portion can be laterally tilted around a longitudinally arranged (in a traveling direction) rolling fulcrum shaft simply by using a rolling correction spring. The specific structure of a rolling fulcrum portion of a transplanting portion of the latter is shown in Japanese Publication Number 2000-41429. According to this publication, a bracket which is shaped like a gate in a side view and of which the bottom surface is open is mounted on the bottom end of a hitch mounted behind a vehicle through an elevating link mechanism, and the bracket has holes on its front and rear sides into which the rolling fulcrum shaft is inserted. On the other hand, a connecting member is extended forward from a place perpendicular to the rolling fulcrum shaft of a transplanting frame constituting a transplanting portion fitted with seedling racks and transplanting pawls, a rolling bearing member shaped like a sleeve to which the rolling fulcrum shaft is inserted is mounted on a tip of this connecting member, the rolling bearing member is fitted to the inside of the bracket, and the rolling fulcrum shaft is inserted to the bracket and the rolling bearing member by aligning the hole centers of the bracket and the rolling bearing member. Therefore, the transplanting portion is connected to the vehicle in a manner that the portion can be laterally tilted around the longitudinally arranged rolling fulcrum shaft. Since the rolling bearing member is mounted in a position away from the transplanting frame as mentioned above, a connecting member for connecting the rolling bearing member to the transplanting frame is required, consequently, leading to weight and cost increases. In addition, since the rolling bearing member is mounted on the transplanting frame through the connecting member in a cantilever condition, it was necessary to use a connecting member with high strength to allow the member to endure a large moment, leading to further weight and cost increases. Therefore, the main purpose of the invention is to allow a rolling bearing member to be mounted on a transplanting frame without using a connecting member that possibly causes the abovementioned weight and cost increases, thereby providing a riding rice transplanter designed and manufactured taking weight and cost reductions into consideration. When the transplanting portion tilts laterally at a certain angle against a vehicle, rolling (laterally tilting operation of the transplanting portion) is restricted within a certain range by allowing a hitch to interfere (be in contact) with the connecting member at only one point. In other words, the rolling restriction of the transplanting portion is implemented. However, when the rolling restriction of the transplanting portion is implemented in a manner that the hitch and the connecting member interfere (be in contact) with each other at only one point as mentioned above, an excessively large force may act on the interference point, causing indent deformation of this interference point. The indent deformation of the interference point may result in a lateral tilting of the transplanting portion beyond the rolling restriction range to cause the transplanting portion to interfere with the hitch and other components of the portion, leading to damage. In order to avoid inconvenience like this, the thickness of a hitch or a connecting member of the conventional machine was increased to obtain greater strength, resulting in weight and cost increases. Therefore, the main purpose of the invention is to provide a riding rice transplanter for which weight and cost reduction measures are implemented by performing the rolling restriction of the transplanting portion without causing the abovementioned weight and cost increases. Summary of the Invention This invention relates to a riding rice transplanter, wherein an intermediate boss 160, or a rolling bearing member of a transplanting portion 15, is mounted on a transverse frame 45 or a transplanting frame 20 in a direction perpendicular to the intermediate boss 160 so that at least a part of the intermediate boss 160 overlaps with the transverse frame 45 in the plan view. Therefore, even if a hitch bed 161 or a connecting member for connecting the intermediate boss 160 and the transverse frame 45 becomes necessary, the lighter and less expensive hitch bed 161 than those of the prior art can be used because the hitch bed 161 is reduced in size and a moment acting on the bed is reduced, thus bringing an effect capable of reducing the weight and cost of the riding rice transplanter. In a riding rice transplanter, an intermediate boss 160, or a rolling bearing member of a transplanting portion 15, is mounted directly on a transverse frame 45, or a transplanting frame 20 perpendicular to the intermediate boss 160. Therefore, even if a hitch bed 161, or a connecting member for connecting the intermediate boss 160 and the transverse frame 45 becomes necessary, the lighter and less expensive hitch bed 161 than those of the prior art can be used because the hitch bed is reduced in size and a moment acting on the bed is almost eliminated, thus bringing an effect capable of reducing the weight and cost of the riding rice transplanter. In a riding rice transplanter, the transverse frame 45, or a transplanting frame perpendicular to the intermediate boss 160 serving as the rolling bearing member of the transplanting portion 15, is provided with a cut-off portion 167 along an external surface of the intermediate boss 160, and the intermediate boss 160 is installed to the cut-off portion. Therefore the intermediate boss 160 can be directly mounted on the transverse frame 45 by means of welding to eliminate a connecting member used in the prior art, thus bringing an effect capable of reducing the weight and cost of the riding rice transplanter. In a riding rice transplanter coupled to a vehicle 1 so as to allow a transplanting portion 15 to tilt laterally around a longitudinally arranged rolling fulcrum shaft 97, interference portions for preventing the transplanting portion 15 from tilting beyond a certain range against the vehicle 1 are provided to several places for each rightward and leftward tilting directions, thereby a force acting on each interference portions A, B, C, D, and E is made smaller than the prior art and the parts that interfere are lighter and less expensive than the prior art, thus bringing an effect capable of reducing the weight and cost of the riding rice transplanter. In a riding rice transplanter linked to a vehicle 1 so as to allow a transplanting portion 15 to tilt laterally around a longitudinally arranged rolling fulcrum shaft 97, a hitch 24 linked to the vehicle 1 and an intermediate boss 160 or a rolling bearing member connected to a transverse frame 45 serving as a part perpendicular to the rolling fulcrum shaft 97 in a transplanting frame 20 of the transplanting portion 15 are connected by the rolling fulcrum shaft 97. A hitch bed 161 or a connecting member for connecting the intermediate boss 160 to the transverse frame 45 at multiple points is constructed so as to interfere with the hitch 24 at multiple points when the transplanting portion 15 tilts laterally in a certain posture against the vehicle 1; thereby, a force acting on each portion A, B, C, D, and E, where the hitch 24 interferes with the hitch bed 161, is made smaller than the prior art, and the hitch 24 and the hitch bed 161 are lighter and less expensive than the prior art, thus bringing an effect capable of reducing the weight and cost of the riding rice transplanter. Brief Description of the Drawings Fig. 1 is a general side view of the riding rice transplanter; Fig. 2 is a general plan view of the riding rice transplanter; Fig. 3 is a side view of the transplanting portion; Fig. 4 is a plan view of the transplanting portion; Fig. 5 is a plan view explaining the transplanting portion; Fig. 6 is a schematic front view of the transplanting portion; Fig. 7 is a front view of the transplanting frame; Fig. 8 is a side view of the transplanting frame; Fig. 9 is a horizontal sectional view of the transplanting frame; Fig. 10 is a left plan view of the transplanting frame; Fig. 11 is a right plan view of the transplanting frame; Fig. 12 is a sectional view explaining the left side of the transplanting frame; Fig. 13 is a fragmentary perspective view explaining the transplanting frame; Fig. 14 is a view explaining the seedling take-out portion; Fig. 15 is a sectional view explaining the seedling feeding case; Fig. 16 is a view explaining the speed change shaft portion; Fig. 17 is a view explaining the changeover mechanism; Fig. 18 is a view explaining the transplanting pawl unit clutch portion; Fig. 19 is an appearance view explaining the transplanting pawl unit clutch portion; Fig. 20 is a view explaining the side bumper portion; Fig. 21 is a front view of the rolling fulcrum portion; Fig. 22 is a sectional rear view of the rolling fulcrum portion; Fig. 23 is a side view of the rolling fulcrum portion; Fig. 24 is a sectional side view of the rolling fulcrum shaft; Fig. 25 is a plan view of the rolling fulcrum shaft; Fig. 26 is an exploded side view of the rolling fulcrum shaft; Fig. 27 is a sectional rear view of the rolling fulcrum shaft showing rolling restriction; Fig. 28 is a side view of the rolling fulcrum shaft showing rolling restriction; Fig. 29 is a perspective appearance view of the rolling fulcrum shaft bearing portion of a transplanting side of a modification; and Fig. 30 is a sectional side view of the rolling fulcrum shaft bearing portion of the transplanting side of the modification. The Best Mode of Embodiment of the Invention Now some embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a general side view of a riding rice transplanter, Fig. 2 is a plan view of the same, and item 1 in the drawing is a vehicle boarded by a worker, wherein an engine 2 is mounted on a vehicle frame 3, rice field traveling front wheels 6 are supported by a front portion of a longitudinally extended transmission case 4 through a front axle case 5, and rice field traveling rear wheels 8 are supported by a rear axle case 7 of a rear portion of the transmission case 4. Furthermore, both ends of a bonnet 9 covering the engine 2 are equipped with a spare seedling racks 10, the transmission case 4 is covered by a body cover 11 of the vehicle boarded by the worker, a driving seat 13 is installed on top of a cab 12 on the rear side of the body cover 11, and a rear portion of the bonnet 9 in front of the driving seat 13 is provided with a steering wheel 14. Item 15 in the drawing is a transplanting portion equipped with seedling racks 16 for transplanting in four ridges. A plurality of rice transplanting pawls 17 and the forward inclining seedling racks 16 made of synthetic resin with high front and low rear portions is supported by a transplanting frame 20 through a lower rail 18 and a guide rail 19 in a manner capable of reciprocating and sliding laterally. A rotary case 21 which rotates unidirectionally at a constant speed is supported by the transplanting frame 20, a pair of pawl cases 22 are symmetrically arranged across a rotating axis of the rotary case 21, and the rice transplanting pawls 17 are installed at ends of the pawl cases 22. The right and left side frames 23 are vertically mounted on the right and left ends of a front portion of the transplanting frame 20 to support the seedling racks 16, a hitch 24 located in a laterally middle portion of the transplanting frame 20 is linked to a vehicle 1 through an elevating link mechanism 27, including a top link 25 and a lower link 26, a hydraulic elevating cylinder 28 provided to the vehicle 1 is connected to the lower link 26, and the transplanting portion 15 is elevated through the elevating link mechanism 27 when the hydraulic elevating cylinder 28 is actuated. When the transplanting portion 15 is lowered, a plant of seedlings is taken out by the rice transplanting pawls 17 from the seedling racks 16, which are laterally reciprocating and sliding to enable continuous rice transplanting. In the drawing, item 29 is a main speed change lever, item 30 is a seedling supply lever enabling operation such as a travel stop not only in a position boarding the vehicle but also in a position out of the vehicle, item 31 is a transplanting elevating lever, item 32 is a main clutch pedal, item 33 is the right and left braking pedals, item 34 is a central float for leveling two ridges, item 35 is a side float for leveling one ridge, item 36 is a side ridge fertilizer distributor for four ridges, and item 37 is the auxiliary wheels arranged on external sides of the rear wheels 8. The side ridge fertilizer distributor 36 comprises a fertilizer hopper 38 for containing fertilizer, a fertilizer dispensing case 39, a turbo blower type blower 42 for discharging fertilizer to a side ridge forming device 40 of a central float 34 and a side float 35 through a flexible type conveying hose 41, and a cylindrical air tank 43, wherein the blower 42 is mounted on a right end of the air tank 43, the fertilizer dispensing cases 39 for four sets, namely for four ridges, are arranged over the upper ends of the air tank 43, and the top ends of the seedling racks 16 are closely arranged on a rear side of the fertilizer hopper 38. As shown in Fig. 3 through Fig. 12, the transplanting frame 20 serving also as a transmission case of the transplanting portion 15 comprises the right and left longitudinal frames 44a and 44b made from a pipe for two ridges each and a transverse frame 45 made from a pipe for connecting front ends of the right and left longitudinal frames 44a and 44b, wherein cross shaped frame joints (cross pipe joints) 46 formed by bulge processing are fixed to each rear end of the longitudinal frames 44a and 44b by welding, and the rotary case 21 is rotatably supported by the frame joints 46 through a rotating shaft 47. Cross shaped frame joints (cross pipe joints) 48a and 48b formed by bulge processing are fixed to the longitudinal frames 44a and 44b and the transverse frame 45 by welding, thereby the longitudinal frames 44a and 44b and the transverse frame 45 are integrally connected to a square space having one side open toward the rear of the body in a plan view to form the lightweight transplanting frame 20 at low cost. A transplanting input shaft 49 is protruded from a front surface of the right frame joint 48b located at a right corner of a front end of the transplanting frame 20 to transmit a driving force from a PTO shaft of the transmission case 4 to the transplanting input shaft 49 through a universal joint shaft 50, and the transplanting input shaft 49 is coupled to a right end of a transplanting drive shaft 51 inserted into the transverse frame 45 through bevel gears 49a and 52. A front end of a transplanting pawl drive shaft 53 inserted to the right and left longitudinal frames 44a and 44b is coupled to the right and left ends of the transplanting drive shaft 51 through the bevel gears 52 and 54 and a safety clutch 55, and a rear end of the transplanting pawl drive shaft 53 is coupled to the rotating shaft 47 through the bevel gears 56a and 56b and a transplanting pawl unit clutch 57 to drive the rice transplanting pawls 17. The seedling feeding shaft 58 for laterally feeding the seedling racks 16 and for longitudinally feeding seedlings on the seedling racks 16 is coupled to a left end of the transplanting drive shaft 51 through a seedling feeding case 59 made of aluminum die cast, wherein a flange portion 61 at one end of the feeding case 59 is fixed by bolts to a welding flange 60 provided to a leftward connecting end portion of the left frame joint 48a, a left end of the seedling feeding shaft 58 is inserted to and supported by another end of the seedling feeding case 59, a speed change mechanism 64 comprising two sets of changeover gears 62 and 63 for changing speed between high and low is arranged between the transplanting drive shaft 51 and the seedling feeding shaft 58 inside the seedling feeding case 59, and a left half and a right half of the seedling feeding shaft 58 are arranged to a longitudinal seedling feeding camshaft 65 and a seedling rack transverse feed threaded shaft 66, respectively, across an approximately middle portion of the laterally viewed machine body, thereby performing the lateral feed of the seedling racks 16 and longitudinal feeding of seedlings on the seedling racks 16 at the time of rotational drive of the seedling feeding shaft 58 at two, namely high and low, speeds. As shown in Fig. 10 and Fig. 11, a transplanting depth adjusting fulcrum shaft 67 is rotatably supported by a lower side of a front end of the transplanting frame 20, and brackets 68 and 69 on a top of a rear end of the central float 34 and on a top of a rear end of the right and left side floats 35 are connected to the transplanting depth adjusting fulcrum shaft 67 through transplanting depth adjusting links 70 and 71. Thus a change of a float tilting angle (transplanting depth) is detected by an elevating link 72 linked to a front end of the central float 34, and reference transplanting depth can be adjusted by a transplanting depth adjusting lever 73 of which the base end is fixed to the transplanting depth adjusting fulcrum shaft 67. The L-shaped right and left side bumpers 74 protruding outwards are mounted on the right and left ends of the transplanting depth adjusting fulcrum shaft 67 through a mounting member 75 in a foldable manner. As shown in Fig. 8, Fig. 10 and Fig. 11, a base end of the right and left marker supporting stays 77 for supporting the right and left line drawing markers 76 in a foldable manner (ups and downs) is fixed by welding on external top surfaces of the right and left frame joints 48a and 48b. The marker supporting stay 77 is formed with an L-shaped pipe, and the longitudinally arranged longitudinal stay 77a is fixed by welding on an approximately middle portion of the frame joints 48a and 48b inline and in contact with a vertical surface of approximately the same height. Transverse stay portions 77b are laterally protruded outward in front of the longitudinal frames 44a and 44b, the line drawing marker 76 is supported by a mounting shaft 78 at a tip of the transverse stay portion 77b through marker beds 79 in a foldable manner, and the transverse stay portion 77b of the left marker supporting stay 77 is positioned in front of the seedling feeding case 59 to function as a bumper for protecting the seedling feeding case 59. As shown in Fig. 13, the right and left marker supporting stays 77 have a base end of the longitudinal stay portion 77a fixed by welding on the internal side surfaces of right and left reinforcing members 80 and 81 for installing the base ends of the right and left side frames 23 on the sides of the frame joints 48a and 48b, thereby providing supporting strength for the side frames 23, and the marker supporting stay 77 is improved. As shown in Fig. 14, a seedling picking adjusting plate 83 that moves a seedling take-out plate 82 at the lower end of the seedling racks 16 up and down to adjust seedling amount is supported by a guide member 84 of the transplanting frame 20 through a guide rod 85 in a movable up and down manner. An engaging plate 87 engaged with a hook 86 of the adjusting plate 83 is provided to a laterally arranged seedling picking amount adjusting shaft 88. The number of seedlings picked by the rice transplanting pawls 17 is adjusted by operating a seedling picking amount adjusting lever 89 linked to the left end of the seedling picking amount adjusting shaft 88. Both the right and left ends of the transverse shaft portion 88a of the seedling picking amount adjusting shaft 88 are rotatably supported by a bearing plate 90 fixed to the seedling feeding case 59 and a right reinforcing member 81. The left end of the transverse shaft portion 88a is constructed on the longitudinal shaft portion 88b by folding forward at approximately 90° at a position closer to the external side than the seedling feeding case 59, and the front end of the longitudinal shaft portion 88b is constructed on a lever linking portion 88c by folding inward at approximately 90° in front of the seedling feeding case 59. The base end of an L-shaped seedling picking amount adjusting lever 89 is fixed with two screws 91 on the lever linking portion 88c. The tip of the seedling picking amount adjusting lever 89 is diagonally extended through a lever guide 92 to the upper front to come between the left rear wheel 8 and the auxiliary wheel 37. The seedling feeding case 59 is protected and surrounded by a transverse shaft portion 88a at the left end of the seed!ing picking amount adjusting shaft 88, a longitudinal shaft portion 88b and a lever linking portion 88c, thereby to allow the case to function as a bumper, and the conveying hose 41 for a leftmost transplanting ridge is positioned in a clearance 93 between the seedling feeding case 59 and the seedling picking amount adjusting shaft 88. The hitch 24 is provided with upper and lower link shafts 94 and 95 for linking a top link 25 and a lower link 26. A rolling bearing member 160 like a sleeve provided approximately in the middle of the transverse frame 45 of the transplanting frame 20 is rotatably linked to the lower end of the hitch 24 through a rolling fulcrum shaft 97. A hydraulic rolling cylinder 99 is mounted on a mounting seat 98 at an upper end of the hitch 24 to link a tip of a piston rod 100 of the hydraulic rolling cylinder 99 with a fixing bracket 101 at the upper end of the right side frame 23. A gear pump 102 for reciprocating the double action hydraulic rolling cylinder 99, a reversible electric motor 103 for reversibly driving the gear pump 102, and an oil tank 104 are integrally provided to the hydraulic rolling cylinder 99. A rolling correction spring 106 is provided between a receiving plate 105 fixed on the top of the mounting seat 98 and the right and left end brackets on the rear side of the seedling racks 16. When a lateral tilt of the transplanting portion 15 is detected by a pendulum type rolling sensor 108 provided on a sensor table 107 of the transverse frame 45 on the left side of the hitch 24, the piston rod 100 of the hydraulic rolling cylinder 99 is extended and retracted to laterally swing (tilt) the transplanting portion 15 around the rolling fulcrum shaft 97 in order to keep the transplanting portion 15 horizontal. A seedling feeding shaft bearing member 109 fixed by welding to the transverse frame 45 on the right side of the hitch 24 is provided, and the seedling feeding shaft bearing member 109 and a fixing bracket 101 at an upper end of the right side frame 23 are connected and reinforced by a diagonal stay 110 thereby improving the rigidity of the right side frame 23 by applying the lightest weight structure and securing satisfactory rolling performance of the transplanting portion 15. The approximately middle portion of the seedling feeding shaft 58 is rotatably supported by the seedling feeding shaft bearing member 109, and both ends of the seedling rack transverse feed threaded shaft 66 are supported between a bearing plate 111 fixed on the right marker supporting stay 77 and the seedling feeding shaft bearing member 109 through the bearing 112. The right end of the longitudinal seedling feeding camshaft 65 is coupled to and supported by the left side of the seedling rack transverse feed threaded shaft 66 through the seedling coupling 113, and the left end of the longitudinal seedling feeding camshaft 65 is coupled to and supported by the seedling feeding case 59. The longitudinal seedling feeding camshaft 65 and the seedling rack transverse feed threaded shaft 66, which are formed by dividing the seedling feeding shaft 58 on the right and left sides, are provided with both ends supported structure to enhance supporting strength. The right end of the longitudinal seedling feeding camshaft 65 is coaxially coupled to the seedling rack transverse feed threaded shaft 66 to improve the precision of longitudinal seedling feeding. The longitudinal seedling feeding camshaft 65 is made from a steel pipe and the seedling rack transverse feed threaded shaft 66 a solid steel rod. Thus the seedling feeding case 59 and the longitudinal seedling feeding camshaft 65 are arranged on the left side, and the heavy seedling rack transverse feedthreaded shaft 66 arranged on the right side across the laterally middle portion optimizes the lateral balance of the transplanting portion 15. A slide block 114 is engaged with the threads of the seedling rack transverse feed threaded shaft 66 and connected to the seedling racks 16 through a slide block receiver 115 to allow the seedling racks 16 to reciprocate laterally while the seedling rack transverse feed threaded shaft 66 rotates unidirectionally. Right and left longitudinal feed cams 116 are provided to the longitudinal seedling feeding camshaft 65. When the seedling racks 16 move either to the right or left stroke end, the longitudinal feed cams 116 contact a cam follower 117 to rotate a longitudinal roller shaft 119 unidirectionally through a unidirectional clutch 118; thereby, a longitudinal feed belt 123 running around the longitudinal feed rollers 121 and 122 of a pair of the upper and lower longitudinal feed roller shafts 119 and 120 provided on the bottom of the seedling racks 16 will move down by one plant. As shown in Fig. 15 through Fig. 17, the frame joint 48a connected to the seedling feeding case 59 has the welding flange 60 for mounting and fixing the seedling feeding case 59 at a leftward coupling end portion of the frame joint 48a and an indented fitting portion 124 fitted to the coupling end portion of the frame joint 48a protruding to some extent from the welding flange 60 at an internal surface of one side of the seedling feeding case 59. A tapered surface 125 is formed at an external end of the indented fitting portion 124, and an O-ring 126 is provided between the tapered surface 125 and the frame joint 48a; thereby, air-tightness between the frame joint 48a and the seedling feeding case 59 can be achieved in a simple construction and at a low cost when a welding flange 60 and a flange 61 are fastened with bolts 127. The seedling case 59 is provided with a speed change shaft 128 separately from the transplanting drive shaft 51, a spline hole 129 is provided inside the bevel gear 52, and the left end of the drive shaft 51 and the right end of the speed change shaft 128 are fitted with the spline hole 129 to integrally couple the speed change shaft 128 to the drive shaft 51; thereby, the speed change shaft 128 can be easily removed together with the seedling feeding case 59. A bearing 130 is provided between the frame joint 48a and the bevel gear 52; thereby, the bevel gear 52 is rotatably supported by an interior of the leftward coupling end of the frame joint 48a. The welding flange 60 is fixed by welding on a peripheral surface of the coupling end portion of the frame joint 48a positioned closer to the external side than the position of the bearing 130. The inside diameter "b" of a mounting portion of the welding flange 60 is formed to be greater than the inside diameter "a" of the fitting portion of the bearing 130 at the coupling end portion of the seedling feeding case 59 of the frame joint 48a (a The seedling case 59 is formed into an L-shape comprising the longitudinal case portion 59a and the transverse case portion 59b, the flange portion 61 is provided to the right end of the transverse case portion 59b, the speed change mechanism 64 comprising the changeover gears 62 and 63 is built in the longitudinal case portion 59a, and the speed changeover mechanism 131 is built in the transverse case portion 59b. The changeover gears 62 and 63 are equipped with the drive side gears 62a and 63a supported in an idly rotatable manner on the speed change shaft 128 and the driven side gear 62b and 63b coupled and fixed to the left end of the longitudinal seedling feeding cam 65. The changeover mechanism 131 comprises a shift key 135, which is embedded in a keyway 132 of a speed change shaft 128 and of which the tip is selectively engaged to a keyway 134 of the drive side gears 62a and 63a by a force of a sheet spring 133 and a changeover lever 138 linked to the shift key 135 through a shift ring 136 and a shifter 137, wherein a left end operating portion 138a of the changeover lever 138 is protruded to a front side of a left exterior of the seedling feeding case 59; thereby, two, namely high and low, lateral feed speeds can be changed over by pushing and pulling the changeover lever 138 laterally. In the changeover gears 62 and 63, the gears 62a and 63a of the side engaging with the shift key 135 are made of metal such as steel, and the driven side gears 62b and 63b of the other side are made of synthetic resin thereby enabling weight reduction and improved durability. As shown in Fig. 18 and Fig. 19, in the transplanting frame 20, the bevel gears 49a, 52 and 54 are built in the frame joints 48a and 48b at the front side of the transplanting frame 20 in a compact manner, and the bevel gears 56a and 56b and the transplanting pawl unit clutch 57 are built in the frame joint 46 at the rear side in a compact manner to simplify structure and reduce costs. As to the transplanting pawl unit clutch 57, a fixing clutch portion 139 is formed in the bevel gear 56b supported by the rotating shaft 47 in an idly rotatable manner, a movable clutch portion 141 is formed in a slider 140 splined to the rotating shaft 47 in a laterally slidable manner, and in a normal condition, the slider 140 is pressed by a clutch spring 142 to couple (engage the clutch) a fixing clutch portion 139 and a movable clutch portion 141. Furthermore, the frame joint 46 is provided with a clutch operating member 143 for moving back the slider 140 against the force of the clutch spring 142 in a retractable manner, and the clutch operating member 143 is linked to a unit clutch lever (not illustrated) arranged, for example, at a rear side of the seedling racks 16 through the lever 144; thereby, the transplanting pawl unit clutch 57 can be engaged or disengaged by operating the clutch lever. As shown in Fig. 20 (1) and (2), in the side bumper 74, a vertical bumper folding portion 74a is inserted in a mounting member 75, shaped in a square having an open side in a side view, fixed to both ends of the transplanting depth adjusting fulcrum shaft 67 in a vertically movable manner, and a compression spring 146 is provided between a spring seat 145 and the mounting member 75 of a vertical bumper folding portion 74a protruded downward from the mounting member 75. A position regulating plate 147 shaped in Lin contact with a left end surface and a front surface of the mounting member 75 is fixed to the vertical portion 74a, the mounting member 75 is provided with a stopper portion 148 for preventing the regulating plate 147 from swinging backward, and in a position where the regulating plate 147 is in contact with a left end surface of the mounting member 75, a bumper folding horizontal portion 74b is protruded in an extending direction of the transplanting depth adjusting fulcrum shaft 67 to protect a seedling take-out plate 82. On the other hand, the side bumper 74 is pulled upward against the compression spring 146 to swing the bumper folding horizontal portion 74b at approximately 90 degrees, and body width is reduced when the position regulating plate 147 is in contact with the front surface of the mounting member 75 in a bumper accommodating position thereby facilitating the loading of the transplanter to a rear body of a light truck and accommodating the transplanter in a garage. An internal transmission mechanism inside the seedling feeding case 59 comprises two shafts consisting of the longitudinal seedling feeding shaft 65 and a speed change shaft 128, and a simple speed change mechanism 64 and the speed changeover mechanism 131 comprising two sets of the changeover gears 62 and 63 and a shift key 135 are built in the seedling feeding case 59. Therefore, the seedling feeding case 59 is manufactured at a reduced cost for a mold with a compactness and light weight, and a case cover 150 of a left side fixed to the case body of the seedling feeding case 59 through screws 149 can be removed to facilitate replacement of the changeover gears 62 and 63 and inspection of the internal transmission mechanism to improve maintainability. When the transverse case portion 59b of the seedling feeding case 59 is formed into an extended shape, a distance between the longitudinal case portion 59a and the flange portion 61 is increased, and tools are used for installing and removing screws 127. The tools can be easily inserted to the position of the screws 127 to facilitate installation and removal of the seedling feeding case 59 to improve maintainability. The abovementioned construction of each portion of the transplanting portion 15 is intended to reduce the weight and cost of a riding rice transplanter, and construction of the rolling fulcrum portion of the transplanting portion 15 that is a main point of the present invention is also intended to reduce the weight and cost of a riding rice transplanter. The construction of the rolling fulcrum portion will be described in detail according to Fig. 21 through Fig. 28 as follows: The longitudinally extended hitch 24 is connected to the rear side of the vehicle 1 on a longitudinal axis of the machine body or approximately on a longitudinal axis of the machine body through the elevating link mechanism 27, a front portion of the transplanting frame 20 constituting the transplanting portion 15 by installing the seedling racks 16 and the seedling transplanting pawls 17, and a laterally middle portion or an almost laterally middle portion of the transverse frame 45 serving as a laterally middle portion or an almost laterally middle portion of the transplanting frame 20 in a direction perpendicular to the rolling fulcrum shaft 97 are rotatably supported by a longitudinally arranged (in the machine traveling direction) horizontal shaft or an almost longitudinally arranged horizontal shaft having a circular cross-section at a lower end portion of the hitch 24, namely the rolling fulcrum shaft 97. The transplanting portion 15 is elastically supported by right and left rolling correction springs 106 in a horizontal posture, or approximately in a horizontal posture, and is linked to the vehicle 1 so as to allow the transplanting portion 15 to be tilted laterally around an axis of the rolling fulcrum shaft 15. A motion of an actuator, or the hydraulic rolling cylinder 99, is controlled so that a value detected by a rolling sensor 108 for detecting a lateral tilt of the transplanting portion 15 is equal to the value when the transplanting portion 15 is horizontal without tilting laterally; thereby, the transplanting portion 15 can be kept horizontal or almost horizontal even if the vehicle 1 tilts laterally. That is to say, the transplanter is constructed so as to be capable of controlling the rolling. The hitch 24 has a longitudinally extended and tapered shape of which the width at a lower portion is larger than that of an upper portion in a side view, and a cross-section of the hitch has a square shape with one side open backward in a plan view. In addition, a rolling fulcrum shaft bearing portion 151 of the hitch 24 side is provided to a lower portion of the hitch 24. The rolling fulcrum shaft bearing portion 151 of the hitch 24 side has a bracket 152 shaped like a gate in a side view, of which the opening directs downward and which is fixed by welding to a space between the right and left side walls of a lower end portion of the hitch 24, and forms a coupling space 153 together with the transplanting portion 15 of which the right and left sides are enclosed between the right and left side walls of the hitch 24 and of which the top, front, and rear surfaces are closed by a bracket 152 while only a bottom surface is open. Short front and rear bosses (sleeves) 154 and 155 having a cylindrical shaft hole penetrated by the rolling fulcrum shaft 97 are coaxially and perpendicularly inserted to the front and rear surfaces of brackets 152 serving as front and rear surfaces of the coupling space 153. A front portion of a front side boss 154 is allowed to penetrate into a front wall of the hitch 24 so as to make a front end protrude toward a front side of the hitch 24. The front end portion of the front side boss 154 is fixed by welding to the front wall of the hitch 24. A middle portion of a rear side boss 155 is fixed by welding to a rear surface of the bracket 152. End portions of the front and rear bosses 154 and 155 are protruded from the front and rear surfaces of the coupling space 153 toward this interior. The rolling fulcrum shaft 97 is inserted from the front side of the hitch 24 to the front side boss 154 and then to the rear side boss 155. Thus, the rolling fulcrum shaft 97 is inserted to and supported by the lower end portion of the hitch 24 in a condition that the rolling fulcrum shaft 97 penetrates into the coupling space 153. When a stopper plate 156 is fixed by welding to an end portion opposite to an insertion starting end of the rolling fulcrum shaft 97, the rolling fulcrum shaft 97 is inserted from the front side of the hitch 24 to the front side boss 154 and then to the rear side boss 155, and the rolling fulcrum shaft 97 is inserted to and supported by the lower end portion of the hitch 24 in a condition that the rolling fulcrum shaft 97 penetrates into the coupling space 153, the stopper plate 156 is made in contact with the front wall of the hitch 24 thereby to restrict insertion of the rolling fulcrum shaft 97, and the stopper plate 156 is fastened to the front wall of the hitch 24 through bolts 157 and nuts 158 thereby to prevent the rolling fulcrum shaft 97 from pulling off and turning. On the other hand, the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side is provided to the front portion of the transplanting frame 20 constituting the transplanting portion 15 by installing the seedling racks 16 and the rice transplanting pawls 17, namely to the laterally middle portion or the almost laterally middle portion of the transverse frame 45 serving as the laterally middle portion or the almost laterally middle portion of the transplanting frame 20 in a direction perpendicular to the rolling fulcrum shaft 97. The rolling fulcrum shaft bearing portion 159 of this transplanting portion 15 side is constructed by an intermediate boss (sleeve) 160 serving as a rolling bearing member and a hitch bed 161 serving as a connecting member for integrally connecting this intermediate boss 160 to the laterally middle portion, or the almost laterally middle portion of the transverse frame 45, so that at least a part of the intermediate boss 160 overlaps with the transverse frame 45 in a plan view. The intermediate boss 160 has sufficient length to enable the intermediate boss 160 to be longitudinally fitted between the front and rear bosses 154 and 155 of the coupling space 153 of the rolling fulcrum shaft bearing portion 151 at the hitch 24 side in series and has a cylindrical shaft hole penetrated by the rolling fulcrum shaft 97. The hitch bed 161 is connected to the transverse frame 45 at multiple points in a horizontal or almost horizontal posture in a longitudinal direction so that the intermediate boss 160 is in direct contact with a top of the laterally middle portion or the almost laterally middle portion of the transverse frame 45 serving as the transplanting frame 20 in a direction perpendicular to this intermediate boss 160 and so that the intermediate boss 160 is perpendicular to the transverse frame 45 in a plan view. In other words, the hitch bed 161 has at least front and rear connecting surfaces 162 and 163 serving as a plurality of vertical connecting surfaces facing each other in a longitudinal direction of the machine body. The front and rear connecting surfaces 162 and 163 are vertically raised from a front external surface and a rear external surface of the transverse frame 45. Lower portions of the front and rear connecting surfaces 162 and 163 face each other at both sides of the transverse frame 45 in the longitudinal direction of the machine body. Upper portions of the front and rear connecting surfaces 162 and 163 face each other over the transverse frame 45 in the longitudinal direction of the machine body. In addition, the width of the lower portions of the front and rear connecting surfaces 162 and 163 at both sides of the transverse frame 45 are established so as to be larger than the lateral width of the hitch 24. The upper portion protruding over the transverse frame 45 is provided with lateral width and height that enable the upper portion to be fitted into the coupling space 153 of the rolling fulcrum shaft bearing portion 151 at the hitch 24 side and to be penetrated into the intermediate boss 160. The lower portions of the front and rear connecting surfaces 162 and 163 are used as lower part fixing portions 162a and 163a fixed by welding to the transverse frame 45. The upper portions of the front and rear connecting surfaces 162 and 163 are used as upper part fixing portions 162b and 163b for fixing the intermediate boss 160 by welding. The narrow upper part fixing portions 162 b and 163b are integrally extended from laterally middle portions of the lower part fixing portion 162a and 163a. The right and left sides of the lower part fixing portions 162a and 163a are laterally protruded beyond the upper part fixing portions 162b and 163b. Upward end surfaces 162c and 163c are formed at both the right and left sides of an intermediate portion of the front and rear connecting surfaces 162 and 163 serving as an interface between the lower part fixing portions 162a and 163a and the upper part fixing portions 162b and 163b. These upward end surfaces 162c and 163c are formed so as to be in alignment with the height of the highest portion of the peripheral surfaces of the transverse frame 45 (height of a higher point of two points at which a vertical line passing an axis of the transverse frame 45 intersects the peripheral surfaces of the transverse frame 45). Furthermore, the upper part fixing portions 162b and 163b of the front and rear connecting surfaces 162 and 163 protruding over the transverse frame 45 are perpendicularly penetrated by the intermediate boss 160 in a condition where the bottom surface of this intermediate boss 160 is in contact with the transverse frame 45. The front and rear portions of the intermediate boss 160 are fixed by welding to the upper part fixing portions 162b and 163b of the front and rear connecting surfaces 162 and 163. Apart of a middle portion of the intermediate boss 160 contacting the transverse frame 45 is fixed to the transverse frame 45 by welding. The intermediate boss 160 is longitudinally connected to the transverse frame 45 at multiple points (three points) in a horizontal or almost horizontal posture in a condition where the intermediate boss 160 is in contact with the directly upper portion of the laterally middle portion or the almost laterally middle portion of the transverse frame 45 used as the transplanting frame 20 in a direction perpendicular to this intermediate boss 160 and so that the intermediate boss 160 is perpendicular to the transverse frame 45 in a plan view. The front and rear connecting surfaces 162 and 163 are integrally formed by bending a flat steel sheet along a cross-sectional shape of the transverse frame 45 as shown in the drawing. In other words, a flat steel sheet is formed into U with a same curvature as the peripheral surface of the transverse frame 45 having a circular cross-section to form the hitch bed 161 into U in a side view. The front and rear surfaces, facing each other, of the hitch bed 161 having a U-shape in a side view are used as the front and rear connecting surfaces 162 and 163. The hitch bed 161 having a U-shape in a side view is externally fitted to the transverse frame 45 from a lower side. The hitch bed 161 is held and fixed by the transverse frame 45 in a condition where the transverse frame 45 is held by a bottom portion of the hitch bed 161 (holding condition). Contacting edges of the hitch bed 161 against the peripheral surface of the transverse frame 45 are fixed to the transverse frame 45 by welding. The front and rear connecting surfaces 162 and 163 are vertically raised from a front external surface and a rear external surface of the transverse frame 45 as mentioned above. The lower portions of the front and rear connecting surfaces 162 and 163 are made to face each other at both sides of the transverse frame 45 in a longitudinal direction of the machine body. The upper portions of the front and rear connecting surfaces 162 and 163 are made to face each other in a position over the transverse frame 45 in a longitudinal direction of the machine body. Although the front and rear connecting surfaces 162 and 163 may be formed separately, the hitch bed 161 can be formed using a holding member that holds the transverse frame 45 as mentioned above, and the front and rear connecting surfaces 162 and 163 for connecting the transverse frame 45 and the intermediate boss 160 at multiple points can be integrally formed. Thus, the front and rear connecting surfaces 162 and 163 can be constructed and installed more easily than the machine in which the front and rear connecting surfaces 162 and 163 are separately formed. Product dimension error and installation error of the front and rear connecting surfaces 162 and 163 are minimized to obtain good precision. High bonding strength can be easily obtained because of an enlarged welding area between the front and rear connecting surfaces 162 and 163 and the transverse frame 45. In addition, high bonding strength between the transverse frame 45 and the intermediate boss 160 can be obtained. Furthermore, an opening portion at the time of externally fitting the hitch bed 161 serving as the holding member to the transverse frame 45 is closed by the intermediate boss 160 on the rear side. Thus, the intermediate boss 160 and the front and rear connecting surfaces 162 and 163 synergistically increase strength for bonding with the transverse frame 45; thereby, the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side is completely integrated by the transverse frame 45 to obtain greater strength. Therefore, the strength necessary for the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side can be secured to contribute to weight and cost reductions without providing the intermediate boss 160 itself and the hitch bed 161 itself, constituting the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side, with high strength. A cut-off hole 164 is provided to a surface contacting the transverse frame 45 of the U-shaped hitch bed 161 for the purpose of enlarging an area for welding to the transverse frame 45, namely increasing the bonding strength and for the purpose of reducing weight. Enlargement of the area for welding to the transverse frame 45 of the hitch bed 161, namely an increase of the bonding strength, can be also realized by providing the edges of the surface contacting the transverse frame 45 with unevenness as clearly shown by the drawing. The seedling feeding shaft bearing member 109 is fixed to a side of the hitch bed 161 by welding so that the seedling feeding shaft bearing member 109 and the hitch bed 161 serve as reinforcing members for each other thereby further strengthening the hitch bed 161 to further reduce weight and costs and strengthening the seedling feeding shaft bearing member 109 to reduce the weight and costs. The coupling space 153 in the rolling fulcrum shaft bearing portion 151 of the hitch 24 side formed as mentioned above is externally fitted from the upper side onto the upper part fixing portions 162b and 163b of the intermediate boss 160 and the front and rear connecting surfaces 162 and 163 in the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side formed as mentioned above. The intermediate boss 160 and the upper part fixing portions 162b and 163b of the front and rear connecting surfaces 162 and 163 are fitted into the coupling space 153, and the intermediate boss 160 is fitted between the front and rear bosses 154 and 155. These bosses 154, 160 and 155 are arranged in series in a longitudinal direction of the machine body, while keeping the axes of the bosses 154,160 and 155 in alignment. The rolling fulcrum shaft 97 is inserted from the front side of the hitch 24 into the front side boss 154, then to the intermediate boss 160, and finally to the rear side boss 155 in sequence. The stopper plate 156 is kept in contact with a front wall of the hitch 24 to restrict insertion of the rolling fulcrum shaft 97. The stopper plate 156 is connected and fixed to the front wall of the hitch 24 with the bolts 157 and the nuts 158 to prevent the rolling fulcrum shaft 97 from pulling off and turning. The transplanting portion 15 is supported by and connected to the lower end portion of the hitch 24 through the rolling fulcrum shaft 97, and the transplanting portion 15 is linked to the vehicle 1 so as to allow the transplanting portion 15 to tilt laterally around the rolling fulcrum shaft 15. The vehicle 1 is provided with interference portions at multiple points for each rightward and leftward tilting directions to prevent the transplanting portion from tilting beyond a certain range, wherein upward the end surfaces 162c and 163c are formed at both the right and left sides of an intermediate portion of the front and rear connecting surfaces 162 and 163 in the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15, and these upward end surfaces 162c and 163c are formed so as to align with the height of the highest portion of a peripheral surfaces of the transverse frame 45. When the transplanting portion 15 is not tilted against the vehicle 1, the lower ends of the right and left side walls of the hitch 24 corresponding to the right and left sides of the coupling space 153 in the rolling fulcrum shaft bearing portion 151 of the hitch 24 side are upwardly separated from the upward end surfaces 162c and 163c of the front and rear connecting surfaces 162 and 163 and from the highest portion of the peripheral surface of the transverse frame 45. When the transplanting portion 15 is tilted at an specified angle in a right-side up or left-side up manner against the vehicle 1, in order to allow the transplanting portion 15 to be in contact (interfere) with the highest portion of the upward end surfaces 162c and 163c of the front and rear connecting surfaces 162 and 163 and the peripheral surface of the transverse frame 45, the lower ends of the right and left walls of the hitch 24 corresponding to the right and left sides of the coupling space 153 in the rolling fulcrum shaft bearing portion 151 of the hitch 24 side are formed by raising from the other lower ends of the right and left side walls of the hitch 24 by a cut-off 165 having a gate-like shape in a side view. Thereby, a total of three interference portions, A, B, and C, are provided to a place on the upward end surface 162c of the front side connecting surface 162 and on the lower ends of the right and left side walls of the hitch 24 serving as the base for the cut-off 165 of which the upward end surface and lower ends contact (interfere) each other when the transplanting portion 15 is tilted at a specified angle in a right-side up or left-side up manner against the vehicle 1 to a place at the upward end surface 163c of the rear side connecting surface 163 and at the lower ends of the right and left side walls of the hitch 24 serving as the base for the cut-off 165 and to a place at the highest portion of the peripheral portion of the transverse frame 45 and at the lower ends of the right and left side walls of the hitch 24 serving as the base of the cut-off 165. An upper end middle portion of the front and rear connecting surfaces 162 and 163 in the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side when the transplanting portion 15 is not tilted against the vehicle 1, namely an upper end middle portion of the upper part fixing portion 162b and 163b, is inserted inside a cylindrical surface S when a cylindrical surface around an axis of the rolling fulcrum shaft 97 has a radius contacting an internal surface of a top of the bracket 152 in the rolling fulcrum shaft bearing portion 151 of the hitch 24 side, namely contacting a ceiling surface of the coupling space 153. The right and left side portions of the upper ends of the front and rear connecting surfaces 162 and 163 in the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side at the time when the transplanting portion is not tilting against the vehicle 1, namely the right and left side portions of the upper ends of the upper part fixing portions 162b and 163b, are located out of the cylindrical surface S at the time when the cylindrical surface having an axis common to the rolling fulcrum shaft 97 has a radius in contact with an internal surface of the top of the bracket 152 in the rolling fulcrum shaft bearing portion 159 of the transplanting portion 24 side, namely in contact with the ceiling surface of the coupling space 153. When the transplanting portion 15 tilts at a specified angle in a right-side up or left-side up direction against the vehicle 1, the upper part fixing portions 162b and 163b of the front and rear connecting portions 162 and 163 in the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side are constituted so that the right and left side portions of the upper end of the front and rear connecting surfaces 162 and 163 in the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side, namely the right and left side portions of the upper end of the upper part fixing portions 162b and 163b, are in contact (interfere) with the internal surface of the top of the bracket 152 in the rolling fulcrum shaft bearing portion 151 of the hitch 24 side, namely in contact with the ceiling surface of the coupling space 153. Thereby, a total of two interference portions D and E consisting of a place on the right and left side portions of the upper end of the upper part fixing portion 162b located in the front side and the ceiling surface of the coupling space 153 of which right and left side portions and ceiling surface contact (interfere) with each other when the transplanting portion 15 tilts at a specified angle in a right-side up or left-side up direction against the vehicle 1 and a place on the ceiling surface of the right and left side portions of the upper end of the upper part fixing portion 163b and the coupling space 153 located on the rear side are provided. When the transplanting portion 15 tilts at a specified angle in a right-side up or left-side up direction against the vehicle 1, a structural member of the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side and a structural member of the rolling fulcrum shaft bearing portion 151 of the hitch 24 side are constructed so as to be in contact (interfere) with each other at five places simultaneously thereby restricting lateral tilting motion (rolling) of the transplanting portion 15 within a specified range. In order to prevent external corners of the lower end of the right and left side walls of the hitch 24 serving as the base of the cut-off 165 in the rolling fulcrum shaft bearing portion 151 of the hitch 24 side corresponding to one end of the interference portions A, B, and C from being in contact (interfering) with the upward end surfaces 162c and 163c of the front and rear connecting surfaces 162 and 163 in the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side corresponding to the other end of the interfering portions A, B, and C and the highest portion of the peripheral surface, and to prevent one or two of the interference portions A, B, and C, from being subjected to indent deformation, an externally directing rib 166 is provided to the lower end of the right and left side walls of the hitch 24 serving as the base for the cut-off 165 in the rolling fulcrum shaft bearing portion 151 of the hitch 24 side. The bottom of this rib 166 is constructed so as to be in contact (interfere) with the upward end surfaces 162c and 163c of the front and rear connecting surfaces 162 and 163 in the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side and the highest portion of the peripheral surface of the transverse frame 45 thereby making the interfering portions A, B, and C interfere in a face-to-face contact manner. One and the other of the remaining interfering portions D and E interfere in a face-to-face contact manner. As clearly mentioned above, the intermediate boss 160 serving as a rolling bearing member of the transplanting portion 15 is provided to the transverse frame 45 serving as the transplanting frame 20 in a direction perpendicular to the intermediate boss 160 in a manner where at least a part of the intermediate boss 160 overlaps with the transverse frame 45 in a plan view. Thus, even if the hitch bed 161 serving as the connecting member for connecting the intermediate boss 160 and the transverse frame 45 is required, compactness of the hitch bed 161 and reduction of a moment acting on the bed enable the use of a lighter and less expensive hitch bed 161 than the machine according to the prior art, leading to weight and cost reductions of the riding rice transplanter. The transplanting portion 15 can be arranged closer to the vehicle 1 than the machine according to the prior art, operability for operating various operating levers of the transplanting portion 15 side can be improved in a condition that an operator is sitting on the driving seat 13 of the vehicle 1, and reduction of total body length can contribute to improvement in traveling performance. The intermediate boss 160 serving as the rolling bearing member of the transplanting portion 15 is provided directly on the transverse frame 45 serving as the transplanting frame 20 in a direction perpendicular to the intermediate boss 160. Thus, even if the hitch bed 161 serving as the connecting member for connecting the intermediate boss 160 to the transverse frame 45 is required, minimization of the size of this hitch bed 161 and approximate elimination of a moment acting on the bed enable the use of a lighter and less expensive hitch bed 161 than the machine according to the prior art, thereby realizing weight and cost reductions of the riding rice transplanter. The transplanting portion 15 can be arranged closer to the vehicle 1 than the machine according to the prior art, operability for operating various operating levers of the transplanting portion 15 side can be improved in a condition that an operator is sitting on the driving seat 13 of the vehicle 1, and reduction of total body length can contribute to improvement in traveling performance. In a riding rice transplanter having the transplanting portion 15 which is connected to the vehicle 1 so as to allow the transplanting portion 15 to tilt laterally around the longitudinally arranged rolling fulcrum shaft 97, interference portions for preventing the transplanting portion 15 from tilting beyond a certain range against the vehicle 1 are provided in several places in each right and left tilting direction thereby making the force acting on the interference portions A, B, C, D, and E smaller than that of the machine according to the prior art. Therefore, lighter and less expensive interference parts than that of the prior art can be used to realize weight and cost reductions of the riding rice transplanter. In a riding rice transplanter having the transplanting portion 15 which is connected to the vehicle 1 so as to allow the transplanting portion 15 to tilt laterally around the longitudinally arranged rolling fulcrum shaft 97, the hitch 24 connected to the vehicle 1 and the intermediate boss 160 serving as the connecting member for connecting to the transverse frame 45 serving as a part perpendicular to the rolling fulcrum shaft 97 in the transplanting frame 20 of the transplanting portion 15 are connected by the rolling fulcrum shaft 97. The hitch bed 161 serving as the connecting member for connecting the transverse frame 45 to the intermediate boss 160 in several places is constituted so as to interfere with the hitch 24 at multiple points when the transplanting portion 15 tilts in a certain posture of right or left tilting against the transplanting portion 15 thereby making the force acting on the interference portions A, B, C, D, and E between the hitch 24 and the hitch bed 161 smaller than that of the machine according to the prior art. Therefore, the hitch 24 and the hitch bed 161 lighter and less expensive than that of the prior art can be used to realize weight and cost reductions of the riding rice transplanter. Fig. 29 and Fig. 30 show a modification of the rolling fulcrum shaft bearing portion of the transplanting portion 15 side. The rolling fulcrum shaft bearing portion 159A of the transplanting portion 15 side connects the intermediate boss 160 serving as the rolling bearing member of the transplanting portion 15 to the laterally middle portion or the almost laterally middle portion of the transverse frame 45 serving as the transplanting frame 20 arranged in a direction perpendicular to this intermediate boss 160 without using the hitch bed 161 in a horizontal or almost horizontal posture longitudinally so that the intermediate boss 160 is perpendicular to the transverse frame 45 in a plan view. Moreover, when the hitch bed 161 is not used to connect the intermediate boss 160 and the transverse frame 45, a measure where the intermediate boss 160 is made in contact with the transverse frame 45 results in only insufficient bonding strength because the intermediate boss 160 can be fixed by welding to the transverse frame 45 only at one point. In order to solve this problem, a cut-off portion 167 along the external surface of the intermediate boss 160 is provided to the top of the laterally middle portion or the almost laterally middle portion of the transverse frame 45, the intermediate boss 160 is bonded to the cut-off 167 from the upper side, and the external surfaces of the intermediate boss 160 and the transverse frame 45 are fixed by welding around the cut-off portion 167 to secure the necessary welding area and bonding strength. Since the transverse frame 45 is penetrated by the transplanting drive shaft 51, depth of the cut-off portion 167 is established so that the bottom of the intermediate boss 160 penetrating into the transverse frame 45 does not contact the transplanting drive shaft 51. Items 168 and 169 in the drawing are integrally raised from the front and rear portions of the intermediate boss 160 in the rolling fulcrum shaft bearing portion 159A of the transplanting portion 15 side having no hitch bed 161. Items 168 and 169 are front and rear stoppers playing the same role as one side of the interference portions D and E which contact (interfere) the internal surface of the top of the bracket 152 in the rolling fulcrum shaft bearing portion 151 of the hitch 24 side corresponding to the other side, namely the ceiling surface of the connecting space 153, when the transplanting portion 15 tilts at a specified angle in a right-side up or left-side up direction against the vehicle 1, namely the same role as the upper part fixing portion 162b and 163b of the front and rear connecting surfaces 162 and 163 in the rolling fulcrum shaft bearing portion 159 of the transplanting portion 15 side. When the transplanting portion 15 tilts at a specified angle in the right- Side up or left-side up direction against the vehicle 1, the right and left side portions of the upper ends of these stoppers 168 and 169 contact (interfere) the internal surface of the bracket 152 in the rolling fulcrum shaft bearing portion 151 of the hitch 24 side, namely with the ceiling surface of the connecting space 153, thereby restricting the lateral tilting motion (rolling) of the transplanting portion 15 within a specified range. As clearly mentioned above, the cut-off portion 167 along the external surface of the intermediate boss 160 is provided to the transverse frame 45 serving as the transplanting frame in a direction perpendicular to the intermediate boss 160, namely the rolling bearing member of the transplanting portion 15, and the intermediate boss 160 is installed to the cut-off portion 167. Therefore, the intermediate boss 160 can be directly installed to the transverse frame 45 by welding, and the connecting member used in the machine according to the prior art can be eliminated; thereby, weight and cost reductions of the riding rice transplanter can be realized. Reference to copending patent application numbers 1302/DELNP/2003 and 1794/DELNP/2003 is made herein. We claim: 1.A rice transplanter comprising a vehicle(1) and a transplanting portion(15) connected to the vehicle so as to be laterally tilted around a rolling fulcrum shaft(97) along a longitudinal direction of the rice transplanter, characterized in an upper surface of a transplanting transverse frame(45/20) forming a part of the transplanting portion(15) is provided with a rolling bearing member(160) along a longitudinal direction of the rice transplanter so that a front end of the rolling bearing member (160)extends forward beyond the front end of the transplanting transverse frame(45) and a rear end of the rolling bearing member(160) extends rearward beyond the rear end of the transplanting transverse frame(45); and the rolling fulcrum shaft(97) inserted into the rolling bearing member so as to overlap with the transplanting transverse frame(20) in a plan view is supported at both ends by a hitch(24) connected to the vehicle(1). 2. A rice transplanter as claimed in claim 1, wherein the transplanting portion is provided with a hitch bed(161) having a U-shape in a side view and externally fitted around the transplanting transverse frame(45) from a lower side; the hitch bed(161) has front and rear connecting surfaces (161,163) extending upward over the transplanting transverse frame(45); and the rolling bearing member (160)is fixed to the front and rear connecting surfaces. 3. A rice transplanter as claimed in claim 1, wherein an upper surface of the transplanting transverse frame is provided with a cut-off portion(167) extending a direction perpendicular to a longitudinal direction of the transplanting transverse frame and having a shape corresponding to an external surface of the rolling bearing member; and the rolling bearing member is fixed into the cut-off portion(167) 4.A rice transplanter as claimed in claim 1, wherein interference portions(A,B,C,D,E) for preventing the transplanting portion from tilting beyond a certain range against the vehicle are provided in several places for each of rightward and leftward tilting directions. 5.A rice transplanter as claimed in claim 4, wherein the hitch and the hitch bed are configured so as to interfere to each other at multiple points when the transplanting portion tilts around the rolling fulcrum shaft at a specified angle in the rightward or leftward directions against the vehicle.

Documents:

1371-delnp-2003-abstract.pdf

1371-delnp-2003-claims.pdf

1371-delnp-2003-correspondence-others.pdf

1371-delnp-2003-correspondence-po.pdf

1371-delnp-2003-description (complete).pdf

1371-delnp-2003-drawings.pdf

1371-delnp-2003-form-1.pdf

1371-delnp-2003-form-18.pdf

1371-delnp-2003-form-2.pdf

1371-delnp-2003-form-3.pdf

1371-delnp-2003-form-5.pdf

1371-delnp-2003-gpa.pdf

1371-delnp-2003-pct-101.pdf

1371-delnp-2003-pct-210.pdf

1371-delnp-2003-pct-304.pdf

1371-delnp-2003-pct-308.pdf

1371-delnp-2003-pct-332.pdf

abstract.jpg