[0001]The present invention relates to a configuration in the vicinity of an engine in a work vehicle such as a passenger-type rice transplanter, a passenger-type direct seeder, and a tractor.
Background technology
[0002]
　In a passenger-type rice transplanter, which is an example of a work vehicle, the engine is supported by the front part of the machine body, and the radiator and the fan are arranged along the front-rear direction on the right side of the engine, as disclosed in Patent Document 1. There is something that has been done.
[0003]
　In Patent Document 1, a heat shield plate is arranged on the rear side of the engine, and the air that has passed through the radiator is guided by the heat shield plate so as to flow to the left side opposite to the radiator by the blowing action of the fan. .. The heat shield plate makes it difficult for the air that has passed through the radiator to flow from the vicinity of the engine to the rear side, and the temperature rise of the hydrostatic continuously variable transmission arranged on the rear side of the engine is suppressed.
Prior art literature
Patent documents
[0004]
Patent Document 1: Japanese Patent Application Laid-Open No. 2001-199251
Outline of the invention
Problems to be solved by the invention
[0005]
　For work vehicles such as passenger-type rice transplanters, a function has been developed that enables work to be performed while automatically traveling along a predetermined work route. For this automatic travel function, the front wheels are operated. An electric motor that can be operated in a direction may be provided.
　In this case, in a work vehicle in which the engine is supported in the front part of the machine body, the electric motor may be arranged on the rear side of the engine, which is located close to the front wheels.
[0006]
　An object of the present invention is to make effective use of a configuration in which a heat shield plate is arranged on the rear side of an engine in a work vehicle so that an electric motor capable of steering the front wheels is appropriately arranged. There is.
Means to solve problems
[0007]
　The work vehicle of the present invention includes an engine and a radiator supported on the front portion of the machine body, an electric motor arranged on the rear side of the engine and capable of steering the front wheels, and the electric motor in rear view. A heat shield plate arranged between the electric motor and the engine in the front-rear direction of the machine is provided so as to overlap with the above.
[0008]
　According to the present invention, in a work vehicle in which an engine and a radiator are supported in the front part of the machine body, when the electric motor is arranged on the rear side with respect to the engine, the heat shield plate overlaps with the electric motor in the rear view. In addition, because it is placed between the electric motor and the engine in the front-rear direction of the aircraft, even if the heat of the engine flows to the rear side, the heat of the engine is stopped by the blocking plate and directly hits the electric motor. Is reduced.
　As a result, the temperature rise of the electric motor can be suppressed, and the durability of the electric motor can be improved.
[0009]
　In the present invention, it is preferable that the heat shield plate has a heat insulating member.
[0010]
　According to the present invention, since the heat shield plate has the heat insulating member, the state in which the heat of the engine directly hits the electric motor is further reduced, and the durability of the electric motor can be improved.
[0011]
　In the present invention, the radiator is arranged on the right side or the left side with respect to the engine, and a fan that introduces air into the radiator and causes the vicinity of the engine to flow to the opposite side of the radiator is arranged along the radiator. A handle post is provided that supports a steering handle that is located on the rear side of the engine and that can artificially steer the front wheels, and the electric motor is rear-viewed with respect to the handle post. It is preferable that the engine is arranged on the fan side.
[0012]
　According to the present invention, the radiator is located on the right or left side of the engine, the fan is located along the radiator, and the air blown by the fan introduces air into the radiator and passes through the radiator to the engine. It flows in the vicinity to the other side of the radiator.
[0013]
　According to the present invention, a handle post supporting a steering handle that can artificially steer the front wheels is arranged on the rear side with respect to the engine, and an electric motor is a fan with respect to the handle post when viewed from the rear. It is placed on the side and close to the fan.
　At a position close to the fan, the air blowing action of the fan is not so weakened, so that the air that has passed through the radiator easily flows to the opposite side of the radiator and does not easily flow to the rear side (electric motor side). At a position close to the fan, even if the air that has passed through the radiator flows to the rear side (electric motor side), this air is not heated much by the engine.
　From the above points, the state in which the heat of the engine directly hits the electric motor is reduced, and the durability of the electric motor can be improved.
[0014]
　In the present invention, the radiator is arranged on the right side or the left side with respect to the engine, and a fan that introduces air into the radiator and causes the vicinity of the engine to flow to the opposite side of the radiator is arranged along the radiator. It is preferable that the air guide cover is provided on the upper side of the engine so as to guide the air flowing in the vicinity of the engine to the opposite side of the radiator.
[0015]
　According to the present invention, the radiator is located on the right or left side of the engine, the fan is located along the radiator, and the air blown by the fan introduces air into the radiator and passes through the radiator to the engine. It flows in the vicinity to the other side of the radiator.
[0016]
　According to the present invention, since the air guide cover that guides the air flowing near the engine to flow to the opposite side of the radiator is arranged on the upper side with respect to the engine, the air that has passed through the radiator due to the blowing action of the fan , It will flow to the other side of the radiator reasonably without staying near the engine.
　As a result, it becomes difficult for the air that has passed through the radiator to flow to the rear side (electric motor side), the state in which the heat of the engine directly hits the electric motor is reduced, and the durability of the electric motor can be improved.
[0017]
　In the present invention, it is preferable that the air guide cover is formed so as to follow the rotation locus of the outer end portion of the fan in a side view.
[0018]
　According to the present invention, since the air guide cover is formed so as to follow the rotation locus of the outer end portion of the fan in the side view, the air that has passed through the radiator due to the blowing action of the fan can be reasonably moved to the opposite side of the radiator. As the air flows, it becomes difficult for the air that has passed through the radiator to flow to the rear side (electric motor side), and the state in which the heat of the engine directly hits the electric motor is reduced, improving the durability of the electric motor. can.
[0019]
　In the present invention, a handle post is provided which is arranged on the rear side with respect to the engine and supports a steering handle capable of artificially steering the front wheels, and the wind guide cover is supported by the handle post. It is preferable to have.
[0020]
　According to the present invention, the engine has a handle post that supports a steering handle that can artificially steer the front wheels on the rear side of the engine, and a wind guide cover is supported by the handle post. Vibration is difficult to be transmitted to the wind guide cover.
　As a result, the vibration of the air guide cover is suppressed, which is advantageous in terms of preventing damage to the air guide cover.
[0021]
　In the present invention, it is preferable that the air cleaner is arranged above the air guide cover in front view.
[0022]
　According to the present invention, when the air cleaner is placed near the engine, the heat of the engine is blocked by the air guide cover because the air cleaner is placed above the air guide cover in front view. It is difficult to convey to the air cleaner.
　As a result, the temperature rise of the air cleaner can be suppressed, and the intake efficiency of the engine can be improved.
[0023]
　In the present invention, a handle post is provided which is arranged on the rear side with respect to the engine and supports a steering handle capable of artificially steering the front wheels, and right and left support portions are provided from the handle post. An intake pipe that extends to the front side and is supported by the handle post by connecting the air guide cover to the support portion and supplies air from the air cleaner to the engine is viewed from the front. It is preferable that the air cleaner and the engine are connected so as to pass between the right and left support portions and, in a side view, between the air guide cover and the handle post. ..
[0024]
　According to the present invention, a handle post that supports a steering handle that can artificially steer the front wheels is arranged on the rear side with respect to the engine, and right and left supports that extend to the front side from the handle post. A wind guide cover is connected to the part.
　In the above configuration, when the air cleaner is placed above the air guide cover in front view, according to the present invention, the space between the air guide cover and the handle post between the right and left supports. Is effectively used, and the intake pipe connected to the air cleaner and the engine is arranged, which is advantageous in terms of compactness in the vicinity of the air cleaner.
[0025]
　In the present invention, the suction pipe for sucking air into the air cleaner passes between the right and left support portions in a front view and between the air guide cover and the handle post in a side view. In addition, it is preferable that the air cleaner extends downward from the air cleaner and extends sideways toward the fan side when viewed from the rear.
[0026]
　According to the present invention, when a suction pipe for sucking external air into an air cleaner is provided, the space between the air guide cover and the handle post is effectively utilized between the above-mentioned right and left support portions. Since the suction pipe is arranged, it is advantageous in terms of compactness in the vicinity of the air cleaner.
[0027]
　In the present invention, it is preferable that the heat shield plate is connected to the support portion and the air guide cover is connected to the support portion by being connected to the heat shield plate.
[0028]
　According to the present invention, the support portion extending forward from the handle post is used for both the support of the heat shield plate and the support of the air guide cover, which is advantageous in terms of simplification of the structure.
[0029]
　In the present invention, a handle post is provided that is arranged on the rear side with respect to the engine and supports a steering handle capable of artificially steering the front wheels, and assists the steering operation of the front wheels by the steering handle. A power steering mechanism is provided, and a steering shaft built in the steering wheel post to transmit the operation of the steering handle to the power steering mechanism is provided, and the electric motor rotates the steering shaft to operate the steering shaft. It is preferable to steer the front wheels.
[0030]
　According to the present invention, when a power steering mechanism that assists the steering operation of the front wheels by the steering handle is provided, the power steering mechanism is operated when the steering shaft is rotated by the electric motor and the front wheels are steered. Since it assists the electric motor, it is possible to operate the steering of the front wheels without difficulty even with an electric motor with a relatively small output.
[0031]
　In the present invention, a gear mechanism capable of transmitting the power of the electric motor to the steering shaft and a gear case covering the gear mechanism are provided, and the gear case has an upper gear case portion and a lower gear case portion. It is preferable that the outer peripheral portion of the upper gear case portion and the outer peripheral portion of the lower gear case portion are bolted to each other in a state where the gear mechanism is housed between the upper gear case portion and the lower gear case portion.
[0032]
　As described above, when the steering shaft is rotated by the electric motor, a gear mechanism capable of transmitting the power of the electric motor to the steering shaft is often provided.
　According to the present invention, the gear case having the upper gear case portion and the lower gear case portion accommodates the gear mechanism in the gear case in a substantially sealed state, so that the gear mechanism is protected from mud, water, and the like.
[0033]
　In the present invention, it is preferable that the electric motor is attached to the upper surface portion of the upper gear case portion so as to protrude upward from the gear case.
[0034]
　According to the present invention, when mud or water on the ground bounces upward and flies near the electric motor, the mud or water easily hits the lower gear case (lower gear case portion) with respect to the electric motor, and is electrically operated. It is difficult to hit the motor, which is advantageous in terms of protecting the electric motor.
A brief description of the drawing
[0035]
[Fig. 1] Left side view of a passenger-type rice transplanter.
[Fig. 2] It is a plan view of a passenger-type rice transplanter.
[Fig. 3] It is a vertical sectional left side view showing the inside of the bonnet.
FIG. 4 is an exploded perspective view showing the inside of the bonnet.
[Fig. 5] Fig. 5 is a plan view showing the inside of the bonnet.
FIG. 6 is a vertical sectional right side view showing the inside of the bonnet.
FIG. 7 is an exploded perspective view of the vicinity of the air guide cover and the handle post.
FIG. 8 is a front view of the vicinity of the handle post and the heat shield.
FIG. 9 is a rear view of the vicinity of the handle post and the heat shield.
[Fig. 10] Fig. 10 is an exploded perspective view of the vicinity of the handle post.
FIG. 11 is an exploded perspective view of a gear case and a gear mechanism.
FIG. 12 is a vertical sectional front view of a gear case and a gear mechanism.
FIG. 13 is a cross-sectional plan view of a detection member and a steering shaft.
Embodiment for carrying out the invention
[0036]
　1 to 13 show a passenger-type rice transplanter which is an example of a work vehicle. In FIGS. 1 to 13, F indicates a forward direction, B indicates a backward direction, and U indicates an upward direction. , D indicates a downward direction, R indicates a right direction, and L indicates a left direction.
[0037]
(Overall configuration of the passenger-type rice transplanter)
　As shown in FIG. 1, the passenger-type rice transplanter has a link mechanism 4 at the rear of the machine body 3 provided with the right and left front wheels 1 and the right and left rear wheels 2. A hydraulic cylinder 5 that is swingably supported up and down and extends to the rear side to raise and lower the link mechanism 4 up and down is provided, and the seedling planting device 6 is supported at the rear part of the link mechanism 4. ..
[0038]
　As shown in FIGS. 1 and 3, the airframe 3 has a right and left airframe frame 7 arranged along the front-rear direction, a mission case 8 connected to the front portion of the airframe frame 7, and a front portion of the mission case 8. It has a support frame 9 and the like connected to.
[0039]
　As shown in FIGS. 1, 3 and 6, the right and left front axle cases 10 are connected to the right and left portions of the mission case 8, and the right and left front wheels 1 are operated by the front axle case 10. It is supported as possible. The rear axle case 11 is supported by the rear portion of the fuselage frame 7, and the right and left rear wheels 2 are supported by the rear axle case 11.
[0040]
(Structure of Seedling Planting Device)
　As shown in FIGS. 1 and 2, the seedling planting device 6 is provided with a planting transmission case 12, a rotary case 13, a planting arm 14, a float 15, a seedling stand 16, and the like. Has been done.
[0041]
　Four planting transmission cases 12 are arranged side by side in the left-right direction, and the rotating case 13 is rotatably supported on the right and left parts of the rear part of the planting transmission case 12 and is supported at both ends of the rotating case 13. , The planting arm 14 is supported. The seedling stand 16 is supported so as to be movable in the left-right direction.
　As the seedling stand 16 is laterally driven in the left-right direction, the rotary case 13 is rotationally driven, and the planting arm 14 alternately takes out seedlings from the lower part of the seedling stand 16 and plants them on the field surface.
[0042]
(Transmission system from the engine to the continuously variable transmission)
　As shown in FIGS. 3, 4, and 6, the support frame 9 has a right and left vertical wall-shaped horizontal side portion 9a and a right and left horizontal side portion 9a. A plurality of frames 9b and the like connected to each other are provided, and are formed in a rectangular frame shape in a plan view.
[0043]
　The engine 17 is supported by the frame 9b of the support frame 9 via the anti-vibration rubber 18, and the engine 17 is arranged horizontally so that the crank shaft (not shown) of the engine 17 is aligned in the left-right direction. Has been done.
[0044]
　As shown in FIGS. 1, 3 and 5, the output shaft 17a of the engine 17 protrudes to the left side, and the output pulley 17b is attached to the output shaft 17a of the engine 17. A hydrostatic type continuously variable transmission 19 is connected to the upper part of the left side of the mission case 8. The input shaft 19a of the continuously variable transmission 19 extends to the left side, and an input pulley 19b and a fan 19c are attached to the input shaft 19a of the continuously variable transmission 19.
[0045]
　The tension arm 20 is swingably supported up and down on the left lateral side portion 9a of the support frame 9, and the tension ring 21 is supported by the end portion of the tension arm 20 to urge the tension arm 20 upward. A spring (not shown) is provided.
[0046]
　The transmission belt 22 is attached over the output pulley 17b of the engine 17 and the input pulley 19b of the continuously variable transmission 19, and the tension wheel 21 is pressed upward by the lower portion of the transmission belt 22. The tension of the transmission belt 22 is maintained.
[0047]
　The output pulley 17b of the engine 17 is rotationally driven in the counterclockwise direction of FIG. 3 by the power of the engine 17, and the power of the engine 17 is passed through the output pulley 17b of the engine 17 and the transmission belt 22 to the continuously variable transmission 19 Is transmitted to the input pulley 19b of the above, and the input pulley 19b of the continuously variable transmission 19 is rotationally driven in the counterclockwise direction of FIG.
[0048]
　The fan 19c is rotationally driven together with the input pulley 19b of the continuously variable transmission 19, and the cooling air from the fan 19c of the continuously variable transmission 19 flows from the left side to the right side, and the continuously variable transmission 19 and the mission case. Sent to 8.
[0049]
(Transmission system from the continuously variable transmission to the front and rear wheels and the seedling planting device)
　The continuously variable transmission 19 is configured to be continuously variable from the neutral position to the forward side and the reverse side.
[0050]
　The power of the output shaft (not shown) of the continuously variable transmission 19 is the gear shifting type auxiliary transmission (not shown) inside the transmission case 8, the front wheel differential mechanism (not shown), and the front right and left. It is transmitted to the right and left front wheels 1 via a transmission shaft (not shown) inside the axle case 10. The power of the auxiliary transmission is transmitted to the rear axle case 11 via the transmission shaft (not shown), and the right and left rear wheels 2 are transmitted via the transmission shaft (not shown) inside the rear axle case 11. Is transmitted to.
[0051]
　The power branched from the output shaft of the continuously variable transmission 19 and the auxiliary transmission is the inter-stock transmission (not shown), the planted clutch (not shown), and the transmission shaft (not shown) inside the transmission case 8. It is transmitted to the seedling planting device 6 via the seedling planting device 6.
[0052]
(Structure relating to engine and radiator)
　As shown in FIGS. 3 to 6, the radiator 23 is arranged on the right side of the engine 17 along the front-rear direction and is supported by the right lateral portion 9a of the support frame 9. ing. The engine 17 and the radiator 23 are supported by the front portion of the machine body 3 by being supported by the support frame 9.
[0053]
　The output shaft 17a of the engine 17 extends to the right side in addition to the left side. A drive pulley 17c is attached to the output shaft 17a of the engine 17, and the drive pulley 17c of the engine 17 is arranged between the engine 17 and the radiator 23.
[0054]
　A water pump 27 for circulating cooling water is provided between the engine 17 and the radiator 23, and the water pump 27 is supported on the upper right portion of the engine 17. A fan 24 is attached to the pulley 27a of the water pump 27, and the fan 24 is arranged between the engine 17 and the radiator 23 along the radiator 23.
[0055]
　The alternator 25 is supported on the upper right part of the engine 17. A drive belt 26 is attached over the drive pulley 17c of the engine 17, the pulley 27a (fan 24) of the water pump 27, and the pulley 25a of the alternator 25.
[0056]
　The exhaust pipe 28 extends downward from the front portion of the engine 17 and extends outward (left side) with respect to the left lateral portion 9a of the support frame 9. The muffler 29 is supported by the support member 69 so that the muffler 29 is connected to the exhaust pipe 28 and is arranged in the front-rear direction on the outside (left side) with respect to the left lateral portion 9a of the support frame 9. There is.
[0057]
　As shown in FIGS. 1, 2, 3 and 6, a bonnet 30 that covers the engine 17 and the radiator 23 and the like is provided. An opening 30a is opened in the right portion and the left portion of the bonnet 30, and a dustproof net (not shown) is attached to the opening 30a of the bonnet 30.
[0058]
　By the power of the engine 17, the drive pulley 17c of the engine 17 is rotationally driven in the clockwise direction of FIG. 6, the water pump 27 and the alternator 25 are driven, and the fan 24 is rotationally driven in the clockwise direction of FIG.
[0059]
　By the suction and ventilation action of the fan 24, air is sucked from the right opening 30a of the bonnet 30 and introduced into the radiator 23, and the air passing through the radiator 23 is near the engine 17 on the opposite side of the radiator 23. It flows to a certain left side and exits from the left opening 30a of the bonnet 30.
[0060]
(Structure of Handle Post and Power Steering Mechanism)
　As shown in FIGS. 3 and 6, the power steering mechanism 31 is connected to the upper part of the mission case 8. The board 32 is connected to the upper part of the power steering mechanism 31, and the gear case 33 is connected to the board 32. The handle post 34 is connected to the gear case 33.
[0061]
　As shown in FIGS. 8, 9, 10 and 12, in the handle post 34, the substrate 34a connected to the upper gear case portion 33a of the gear case 33, and the intermediate portion 34b and the intermediate portion in which the three legs are connected to the substrate 34a. A round pipe-shaped pipe portion 34c or the like connected to 34b and extended upward is provided.
[0062]
　The steering shaft 35 is built in the handle post 34 and the gear case 33 and is rotatably supported along the vertical direction, and the lower portion of the steering shaft 35 is inserted into and connected to the power steering mechanism 31. The steering handle 36 is attached to the upper end of the steering shaft 35 protruding from the upper end of the pipe portion 34c of the handle post 34.
[0063]
　As shown in FIGS. 3 to 6, the handle post 34 and the power steering mechanism 31 are arranged on the rear side with respect to the engine 17 in a side view. When the operator artificially operates the steering wheel 36, the operation of the steering wheel 36 is transmitted to the power steering mechanism 31 via the steering shaft 35, and the front wheel 1 is steered. The steering operation of the front wheel 1 is assisted by the power steering mechanism 31.
[0064]
　As shown in FIGS. 9 and 12, the steering wheel post 34 is connected to the gear case 33, and the gear case 33 is connected to the power steering mechanism 31 and the substrate 32, so that the operation of the steering handle 36 can be performed by the steering shaft as described above. When the steering wheel post 34 and the gear case 33 are transmitted to the power steering mechanism 31 via the steering wheel 35, the steering wheel post 34 and the gear case 33 are stopped to rotate together with the steering shaft 35.
[0065]
(Structure of Gear Case and Electric Motor)
　As shown in FIGS. 7, 11 and 12, the gear case 33 has an upper and lower two-divided structure having an upper gear case portion 33a and a lower gear case portion 33b, and extends to the right from the handle post 34. ing. The gear mechanism 37 is housed inside the gear case 33 (between the upper gear case portion 33a and the lower gear case portion 33b), and the outer peripheral portion of the upper gear case portion 33a and the outer peripheral portion of the lower gear case portion 33b are bolted to each other. , The gear mechanism 37 is covered with a gear case 33.
[0066]
　In the gear mechanism 37, the transmission shaft 38 rotatably supported along the vertical direction, the transmission gear 39 of Daikei rotatably attached to the transmission shaft 38, and the transmission shaft 38 rotatably attached to the transmission shaft 38. A transmission gear 40 having a small diameter and a transmission gear 41 of a large diameter rotatably attached to the steering shaft 35 are provided, and the transmission gears 40 and 41 are engaged with each other.
[0067]
　The electric motor 42 is attached to the upper surface portion of the right end portion of the upper gear case portion 33a of the gear case 33 so as to protrude upward from the gear case 33. The pinion gear 42a, which is rotationally driven by the electric motor 42, meshes with the transmission gear 39 inside the gear case 33.
[0068]
　As shown in FIGS. 6 and 9, the electric motor 42 is arranged on the rear side with respect to the engine 17, and the electric motor 42 is on the fan 24 side (right side) with respect to the handle post 34 in the rear view. Have been placed.
[0069]
　The electric motor 42 is operated when the automatic traveling described in the following (configuration relating to the automatic traveling) is performed.
　As shown in FIGS. 11 and 12, when the electric motor 42 is operated, the power of the electric motor 42 is transmitted from the pinion gear 42a of the electric motor 42 via the gear mechanism 37 (transmission gears 39, 40, 41 and transmission shaft 38). Then, it is decelerated and transmitted to the steering shaft 35.
[0070]
　As a result, the steering shaft 35 is rotationally operated to steer the front wheels 1 in the same manner as described above (configuration relating to the steering wheel post and the power steering mechanism), and the front wheels 1 are steered by the electric motor 42. The operation is assisted by the power steering mechanism 31.
[0071]
　In the state where automatic traveling is not performed, the electric motor 42 is in a free rotation state. As a result, as described in the above-mentioned (configuration relating to the handle post and the power steering mechanism), when the operator artificially operates the steering handle 36 to steer the front wheel 1, the gear mechanism 37 is used. The electric motor 42 is driven, and the electric motor 42 does not become a resistance to the steering operation of the front wheel 1.
[0072]
　As shown in FIGS. 3 and 6, the gear shift type auxiliary transmission inside the mission case 8 (see the above-mentioned (transmission system from the continuously variable transmission to the front and rear wheels and the seedling planting device)). The auxiliary shift lever 47 for shifting gears is extended upward from the mission case 8.
[0073]
　As shown in FIG. 9, the upper portion of the auxiliary shift lever 47 is rotatably supported around the axis in the vertical direction by the receiving portion 33c formed in the lower gear case portion 33b of the gear case 33. The auxiliary transmission is operated by the operator holding the auxiliary transmission lever 47 and operating it around the axis in the vertical direction.
[0074]
(Structure for detecting the steering angle of the front wheels)
　When the automatic driving described in (Configuration for automatic driving) described later is performed and the steering operation of the front wheels 1 is performed by the electric motor 42, the steering angle of the front wheels 1 is performed. Needs to be detected. The configuration in which the steering angle of the front wheel 1 is detected will be described below.
[0075]
　As shown in FIGS. 9, 11, 12, and 13, a cylindrical detection member 43 made of synthetic resin is attached to the steering shaft 35 inside the intermediate portion 34b of the handle post 34, and the outer peripheral portion of the detection member 43 is attached. A spiral groove 43a is formed in the groove 43a.
[0076]
　Inside the detection member 43, a different diameter portion 35a having an oval cross section is provided on the steering shaft 35. The inner portion of the detection member 43 has a larger diameter than the different diameter portion 35a of the steering shaft 35, and is formed to have a different diameter shape similar to the different diameter portion 35a of the steering shaft 35. Two semi-cylindrical spacers 44 having an inner surface and an outer surface formed in the same different diameter shape as the inner portion of the detection member 43 are prepared.
[0077]
　The steering shaft 35 is inserted into the detection member 43 with the two spacers 44 attached to the different diameter portions 35a of the steering shaft 35. As a result, the detection member 43 can rotate integrally with the steering shaft 35 due to the different diameter portion 35a and the spacer 44 of the steering shaft 35.
[0078]
　As shown in FIGS. 10 and 12, a potentiometer type angle sensor 45 is attached to the intermediate portion 34b of the handle post 34. A detection arm 45a attached to a detection shaft (not shown) of the angle sensor 45 and capable of swinging up and down extends toward the detection member 43, and an engaging pin 45b at the end of the detection arm 45a is provided. , Is inserted into the spiral groove 43a of the detection member 43.
[0079]
　As described in the above (configuration relating to the gear case and the electric motor), when the steering shaft 35 is rotationally operated by the electric motor 42 and the front wheel 1 is steered, the detection member 43 is rotated integrally with the steering shaft 35. Will be done.
[0080] [0080]
　The spiral groove 43a of the detection member 43 is rotated with respect to the detection arm 45a of the angle sensor 45, and the detection arm 45a of the angle sensor 45 is swung up and down by the spiral groove 43a of the detection member 43. .. As a result, the steering angle of the front wheel 1 is detected by the vertical angle of the detection arm 45a of the angle sensor 45.
[0081]
(Structure relating to automatic running)
　As shown in FIGS. 1 and 2, the right spare seedling mounting frame 62 is connected to the right lateral portion 9a of the support frame 9 and extended upward, and the left spare seedling is extended. The mounting frame 62 is connected to the left lateral portion 9a of the support frame 9 and extends upward, and the spare seedling mounting table 63 is supported by the right and left spare seedling mounting frames 62. ..
[0082]
　A support frame 64 along the left-right direction is connected to the upper part of the right and left spare seedling pedestal frames 62, and a GPS antenna 65 is connected to the left-right center portion of the support frame 64.
[0083]
　A support frame 66 is connected upward to the rear of the right and left fuselage frames 7, and the driver's seat 67 is supported by the support frame 66. The control device 68 is attached to the support frame 66 and is located below the driver's seat 67. The vicinity of the lower side of the driver's seat 67 in the support frame 66 is a portion where various harnesses (not shown) are gathered, and is therefore a convenient position for the control device 68.
[0084]
　The control device 68 uses the GPS antenna 65 to position the machine 3 so that the seedling planting device 6 can plant seedlings while the machine 3 automatically travels along a preset work process. Based on the information, the electric motor 42 is operated to steer the front wheel 1.
[0085]
(Structure relating to the air guide cover)
　As shown in FIGS. 3 to 6, in the bonnet 30, the air guide cover 46 is arranged on the front side with respect to the handle post 34 and on the upper side with respect to the engine 17.
[0086]
　The wind guide cover 46 is formed by bending a plate material, and is formed in a mountain shape that is convex upward so as to follow the rotation locus of the outer end portion of the fan 24 in a side view. A heat insulating sheet (not shown) is attached to the upper surface and the lower surface of the above.
[0087]
　As shown in FIGS. 3 to 7, the right mounting portion 46d is connected to the vicinity of the right end portion 46a of the air guide cover 46 and extends to the rear side, and the left mounting portion 46e is the air guiding cover. It is connected to the vicinity of the left end portion 46b of 46 and extends to the rear side.
[0088]
　The right end portion 46a of the wind guide cover 46 is arranged so as to approach the radiator 23 to a position where it overlaps with the fan 24 in a plan view. The rear portion 46c of the wind guide cover 46 extends relatively long to the rear and lower sides, and as shown in FIGS. 8 and 9, the rear portion 46c and the handle of the wind guide cover 46 are viewed from the front and the rear. It overlaps with the post 34.
[0089]
　As shown in FIGS. 4 and 5, the left end portion 46b of the air guide cover 46 is arranged at substantially the same position as the left end portion of the main body of the engine 17 in plan view and front view, and is located at a position substantially the same as that of the output pulley 17b of the engine 17. It is arranged on the right side (engine 17 side), and the space between the left end portion 46b of the air guide cover 46 and the inner surface (left opening portion 30a) a of the bonnet 30 is relatively wide open in the left-right direction.
[0090]
　As shown in FIGS. 3 to 6, the space between the air guide cover 46 and the inner surface of the ceiling portion of the bonnet 30 is relatively wide open in the vertical direction, and the air guide cover 46 and the inner surface of the ceiling portion of the bonnet 30 are connected to each other. A space is formed between them. The area below the air guide cover 46 (on the engine 17 side) and the above-mentioned space pass between the left end portion 46b of the air guide cover 46 and the inner surface of the bonnet 30 (left opening 30a). , Communicating.
[0091]
　As described in the above (configuration relating to the engine and the radiator), the air passing through the radiator 23 is guided by the air guide cover 46 so as to smoothly flow in the vicinity of the engine 17 by the suction and ventilation action of the fan 24. , Is guided to flow smoothly to the left side, which is the opposite side of the radiator 23.
[0092]
(Structure for supporting the air guide cover and the heat shield plate)
　As shown in FIGS. 7 to 10, an elongated plate material bent in a channel shape in a plan view is connected to the substrate 34a of the handle post 34, and the handle post. A right support portion 51 and a left support portion 52 are provided extending from 34 to the front side.
[0093]
　When viewed from the side, the channel-shaped support plate 48 is connected to the substrate 34a of the handle post 34 and the pipe portion 34c. An angle-shaped support portion 49 is provided, and the left and right central portions of the support portion 49 are connected to the support plate 48. The mounting portion 49a in which the elongated plate material is bent in an arc shape is connected to the support portion 49 forward, and the mounting portion 49b is connected to the support portion 49 backward.
[0094]
　The rod-shaped reinforcing member 50 is connected to the right support portion 51 and the support portion 49, and the flat plate-shaped support member 53 is connected to the left support portion 52 and the support portion 49. .. A flat plate-shaped reinforcing member 54 is connected to the support plate 48 and the support member 53, and the flat plate-shaped reinforcing member 55 is connected to the pipe portion 34c of the handle post 34 and the support member 53.
　With the above structure, the right and left support portions 51 and 52 and the support portions 49 are supported by the handle post 34.
[0095]
　A shift lever 56 (see FIGS. 1 to 5) that operates the continuously variable transmission 19 is supported by the support member 53. Right and left hinge members (not shown) that support the bonnet 30 up and down so as to be openable and closable are connected to the right end and the left end of the support portion 49.
[0096]
(Support for the air guide cover and the heat shield plate)
　As shown in FIGS. 7, 8 and 9, the flat plate-shaped heat shield plate 57 is connected to the right support portion 51 and the support portion 49, and shields the heat shield. The hot plate 57 extends downward from the right support portion 51. The controller 58 that operates and operates the electric motor 42 is connected to the mounting portion 49b of the support portion 49 and extends downward.
[0097]
　As shown in FIGS. 3 to 6 and 9, the electric motor 42, the controller 58, and the engine in the front-rear direction of the machine body 3 so that the heat shield plate 57 overlaps the electric motor 42 and the controller 58 in the rear view. It is arranged between the electric motor 42 and the controller 58, and the electric motor 42 and the controller 58 are arranged on the rear side with respect to the heat shield plate 57.
[0098]
　The controller 58 is arranged between the electric motor 42 and the heat shield plate 57 in the front-rear direction of the machine body 3 so as to overlap the electric motor 42 and the heat shield plate 57 in the rear view, and the electric motor 42 is arranged. , Arranged behind the controller 58.
[0099]
　In the heat shield plate 57, a heat insulating sheet (not shown) (corresponding to a heat insulating member) is attached to the front surface and the rear surface of the heat shield plate 57. In this case, the heat insulating sheet 57 is not attached to the heat insulating plate 57, but the heat insulating member can be melted into the inside of the heat insulating plate 57 so that the heat insulating plate 57 has the heat insulating member. ..
[0100]
　As shown in FIGS. 7, 8 and 9, the right mounting portion 46d of the air guide cover 46 is connected to the heat shield plate 57, and the left mounting portion 46e of the air guiding cover 46 is the left support portion 52. Is linked to.
　In this case, a common bolt (not shown) is passed through the right support portion 51, the heat shield plate 57, and the right mounting portion 46d of the air guide cover 46, and the right support portion 51 and the heat shield plate are passed. The right mounting portion 46d of the wind guide cover 46 and the air guide cover 46 are connected to each other, and the air guide cover 46 is connected to the right support portion 51 by being connected to the heat shield plate 57.
[0101]
　The air guide cover 46 is supported by the handle post 34 by being connected to the right and left support portions 51 and 52, and as described in the above-mentioned (configuration relating to the air guide cover), the air guide cover 46 is supported. Is arranged inside the bonnet 30.
[0102]
(Structure relating to air cleaner)
　As shown in FIGS. 3 to 6, inside the bonnet 30, the air cleaner 59 is laterally oriented along the left-right direction and is attached to the attachment portion 49a of the support portion 49, and the air cleaner is attached. The 59 is arranged above the air guide cover 46 in the front view. The air cleaner 59 is arranged on the front side with respect to the handle post 34 in a side view, and is supported by the handle post 34 via the support portion 49.
[0103]
　The intake pipe 60 coming out from the left side of the air cleaner 59 turns downward and extends downward through between the rear portion 46c of the air guide cover 46 and the left mounting portion 46e (see FIG. 7). It is connected to the engine 17.
[0104]
　As the intake pipe 60 passes between the rear portion 46c of the air guide cover 46 and the left mounting portion 46e, the intake pipe 60 passes between the right and left support portions 51 and 52 in front view and side view. The air cleaner 59 and the engine 17 are connected so as to pass between the air guide cover 46 and the handle post 34.
[0105]
　The suction pipe 61 protruding from the lower part of the air cleaner 59 extends to the rear side with respect to the rear portion 46c of the air guide cover 46, and turns to the right to the rear side with respect to the heat shield plate 57. Is extended to the right side, and the suction port 61a of the suction pipe 61 is arranged on the rear side with respect to the radiator 23 and the fan 24.
[0106]
　By arranging the suction pipe 61 on the rear side with respect to the rear portion 46c of the air guide cover 46 and on the rear side with respect to the heat shield plate 57, the suction pipe 61 is arranged on the right and left sides in the front view. It extends downward from the air cleaner 59 so as to pass between the support portions 51a and 52 and pass between the air guide cover 46 (heat shield plate 57) and the handle post 34 in a side view, and is sucked. The pipe 61 extends laterally toward the fan 24 side.
[0107]
　With the above structure, the air outside the bonnet 30 is sucked into the suction port 61a of the suction pipe 61 and supplied to the air cleaner 59 through the suction pipe 61. The air from the air cleaner 59 is supplied to the engine 17 through the intake pipe 60.
[0108]
(The first alternative embodiment of the invention) The
　radiator 23 and the fan 24 may be arranged on the left side of the engine 17 along the front-rear direction.
[0109]
　According to this configuration, the drive pulley 17c of the engine 17 is arranged on the left side of the engine 17, and the electric motor 42 is arranged on the left side with respect to the handle post 34. The output pulley 17b of the engine 17 is arranged on the right side of the engine 17, and the continuously variable transmission 19 is connected to the right part of the mission case 8.
[0110]
(Second alternative embodiment of the invention) The
　fan 24 may be arranged outside the radiator 23 (opposite the engine 17) rather than between the engine 17 and the radiator 23. According to this configuration, it is preferable to provide an electric motor (not shown) for rotationally driving the fan 24.
Industrial applicability
[0111]
　The present invention can be applied not only to a passenger-type rice transplanter but also to a work vehicle such as a passenger-type direct seeding machine or a tractor.
Description of the sign
[0112]
　1 Front wheel
　3 Aircraft
　17 Engine
　23 Radiator
　24 Fan
　31 Power steering mechanism
　33 Gear case
　33a Upper gear case part
　33b Lower gear case part
　34 Handle post
　35 Steering shaft
　36 Steering handle
　37 Gear mechanism
　42 Electric motor
　46 Wind guide cover
　51 Support part
　52 Support part
　57 Heat shield
　59 Air cleaner
　60 Intake pipe
　61 Intake pipe

WE CLAIMS

The engine and radiator supported in the front part of the machine, the
　electric motor arranged on the rear side of the engine and capable of steering the front wheels, and the
　electric motor so as to overlap with the electric motor in the rear view. A work vehicle provided with a heat shield plate arranged between the electric motor and the engine in the front-rear direction of the machine body.
[Claim 2]
　The work vehicle according to claim 1, wherein the heat shield plate has a heat insulating member.
[Claim 3]
　The radiator is located on the right or left side of the
　engine, and a fan that introduces air into the radiator and causes the vicinity of the engine to flow to the opposite side of the radiator is located along the radiator of the
　engine . A handle post is provided to support a control handle that is arranged on the rear side with respect to the front wheel and can artificially steer the front wheel, and the
　electric motor is rear-viewed on the fan side with respect to the handle post. The work vehicle according to claim 1 or 2, which is arranged in.
[Claim 4]
　The radiator is located on the right or left side of the
　engine, and a fan that introduces air into the radiator and causes the vicinity of the engine to flow to the opposite side of the radiator is located along the radiator of the
　engine . 6. Work vehicle.
[Claim 5]
　The work vehicle according to claim 4, wherein the air guide cover is formed so as to follow a rotation locus of an outer end portion of the fan in a side view.
[Claim 6]
　A claim in which a handle post is provided that is located rearward to the engine and supports a steering handle that can artificially steer the front wheels, and the
　wind guide cover is supported by the handle post. The work vehicle according to 4 or 5.
[Claim 7]
　The work vehicle according to any one of claims 4 to 6, wherein the air cleaner is arranged on the upper side of the air guide cover in a front view.
[Claim 8]
　A handle post is provided on the rear side of the engine to support a steering handle capable of artificially steering the front wheels, with
　right and left supports extending forward from the handle post. The air intake pipe, which is supported by
　the handle post by connecting the air guide cover to the support portion and
　supplies the air from the air cleaner to the engine, is right and left in front view. The work vehicle according to claim 7, wherein the air cleaner and the engine are connected so as to pass between the support portions and, in a side view, between the air guide cover and the handle post. ..
[Claim 9]
　The air so that the suction pipe for sucking air into the air cleaner passes between the right and left supports in front view and between the air guide cover and the handle post in side view. The work vehicle according to claim 8, which extends downward from the cleaner and extends sideways toward the fan side in a rear view.
[Claim 10]

　The work vehicle according to claim 8 or 9, wherein the heat shield plate is connected to the 　support portion, and the air guide cover is connected to the support portion by being connected to the heat shield plate.
[Claim 11]
　A power steering mechanism that is arranged on the rear side of the engine and is provided with a handle post that supports a steering handle capable of artificially steering the
　front wheels, and assists the steering operation of the front wheels by the steering handle. The steering wheel is provided inside the
　steering wheel post to transmit the operation of the steering handle to the power steering mechanism, and the
　electric motor rotates the steering shaft to steer the front wheels. The work vehicle according to any one of claims 1 to 10 to be operated.
[Claim 12]
　A gear mechanism capable of transmitting the power of the electric motor to the steering shaft and a gear case covering the gear mechanism are provided. The
　gear case has an
　upper gear case portion and a lower gear case portion, and the upper gear case portion and the gear case portion. The work vehicle according to claim 11, wherein the outer peripheral portion of the upper gear case portion and the outer peripheral portion of the lower gear case portion are bolted to each other in a state where the gear mechanism is housed between the lower gear case portion and the lower gear case portion.
[Claim 13]
　The work vehicle according to claim 12, wherein the electric motor is attached to an upper surface portion of the upper gear case portion so that the electric motor protrudes upward from the gear case.