Work vehicle

Abstract

To provide a work vehicle that has excellent workability and reduces the loss of power transmission to a work device.SOLUTION: The work vehicle includes a drivable vehicle body and a coupling device. The coupling device has a driven shaft to which power is input. A work device driven by power input to the driven shaft is connected to the coupling device. The coupling device is mounted on the vehicle body. The coupling device has a prime mover having a drive shaft that outputs power. The drive shaft of the prime mover is directly or indirectly connected so as to be capable of transmitting power to the driven shaft of the work device.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a work vehicle to which a work device can be connected.

Background Art

[0002] Conventionally, a work vehicle such as a tractor includes a prime mover, a connecting device for connecting a work device such as a tiller, and a PTO mechanism for transmitting the output of the prime mover to the work device connected to the connecting device. The work device is connected to the work vehicle via the connecting device and operates by the output of the prime mover transmitted from the PTO mechanism to perform a predetermined work (tilling work, cleaning work, etc.).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the output of the prime mover is transmitted to the work device via the PTO mechanism as described above, an output transmission loss occurs due to the influence of mechanical resistance and the like in the PTO mechanism, and the energy efficiency decreases. In addition, in order to surely extract a sufficient output via the PTO mechanism, there is also a problem that the driving load of the prime mover increases to compensate for the output transmission loss.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a work vehicle with less output transmission loss to the work device and excellent workability.

Means for Solving the Problems

[0006] The present invention employs the following technical means to achieve the above object.

[0007] A work vehicle according to one aspect of the present invention includes a travelable vehicle body and a coupling device having a driven shaft to which power is input and a working device driven by the power input to the driven shaft, the coupling device being attached to the vehicle body, the coupling device having a prime mover that outputs power, and the drive shaft of the prime mover being directly or indirectly connected to the driven shaft of the working device so as to be capable of power transmission.

[0008] The prime mover may be an electric motor that is driven by receiving power supply from the vehicle body.

[0009] The coupling device has a link mechanism pivotally supported by the vehicle body and a hitch frame connected to the link mechanism and to which the working device is connected, and the hitch frame may include a bracket to which the prime mover is attached.

[0010] The coupling device is attached to the front or rear portion of the vehicle body in the traveling direction of the vehicle body, and the bracket may be swingably connected to the hitch frame about an axis extending in the vehicle width direction.

[0011] The coupling device may have a suspension device that swingably suspends and supports the prime mover on the hitch frame.

[0012] The suspension device has a first end portion and a second end portion opposite to the first end portion, the first end portion is connected to the upper portion of the hitch frame, and the second end portion may be connected to a position away from the axis direction of the drive shaft from the swing center of the bracket in the prime mover. The suspension device may be a spring member that applies a predetermined tensile force upward to the prime mover.

[0013] The suspension device may be a spring member that applies a predetermined tensile force upward to the prime mover.

[0014] The drive shaft of the prime mover may be engageable with the driven shaft of the working device and capable of power transmission in an engaged state.

[0015] Either one of the drive shaft of the prime mover or the driven shaft of the working device is a hollow shaft, and the other of the drive shaft of the prime mover or the driven shaft of the working device may be a shaft body that can be fitted into the shaft of the hollow shaft.

[0016] The connecting device may have a universal joint that can swingably connect the driven shaft of the working device to the drive shaft of the prime mover.

[0017] The prime mover has a housing that holds the drive shaft, and the bracket has a protective member formed of a metal material with a greater ionization tendency than the base material of the bracket, and the protective member may be provided in contact with both the housing and the bracket.

[0018] The protective member may be removably connected to the housing or the bracket.

[0019] The housing is closely connected to the bracket, and the protective member may be disposed below the housing.

Advantages of the Invention

[0020] According to the present invention, it is possible to provide a work vehicle with less output transmission loss to the working device and excellent workability.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0022] An embodiment of the present invention will be described with reference to the drawings.

[0023] The work vehicle 1 of the present embodiment is a travelable vehicle. As shown in FIGS. 1 and 2, the work vehicle 1 of the present embodiment is a tractor, and includes a vehicle body 2, a traveling device 3, a driver's seat 4, a main prime mover 5 for traveling, a connecting device 6, a battery 8, and a moving mechanism 80. Note that the work vehicle 1 according to the present invention is not limited to a tractor. For example, the work vehicle 1 according to the present invention may be an agricultural machine, a construction machine, a transport machine, a utility vehicle, or the like other than a tractor.

[0024] Hereinafter, the longitudinal direction of the vehicle body 2 in the straight-ahead traveling direction of the work vehicle 1 (the directions indicated by the arrows X1 and X 2 in FIGS. 1 and 2) is defined as the front-rear direction, the width direction of the vehicle body 2 (the directions indicated by the arrows Y1 and Y2 in FIG. 2) is defined as the left-right direction, and the height direction of the vehicle body 2 (the directions indicated by the arrows Z1 and Z2 in FIG. 1) is defined as the up-down direction for explanation.

[0025] The vehicle body 2 is formed by combining metal frame materials and the like, and is supported by the traveling device 3. The vehicle body 2 includes a bonnet 2A and a cabin 2B. The bonnet 2A is provided at the upper front part of the vehicle body 2 and covers the front of the vehicle body 2 above the driver's seat 4. In other words, the driver's seat 4 is provided behind the bonnet 2A at the upper part of the vehicle body 2. The cabin 2B covers the periphery of the driver's seat 4 at the upper part of the vehicle body 2. The cabin 2B is a protection mechanism for protecting the driver's seat 4. Note that the work vehicle 1 may be provided with a canopy instead of the cabin 2B as the above protection mechanism.

[0026] As shown in FIG. 1, a clutch housing 9A and a transmission case 9B are provided at the rear part of the vehicle body 2. The clutch housing 9A houses a clutch and is connected to the main prime mover 5. The transmission case 9B houses a transmission, a rear-wheel differential device, etc. and is connected to the clutch housing 9A.

[0027] The traveling device 3 supports the vehicle body 2 so that it can travel. The traveling device 3 of the present embodiment is a wheel rotatably provided with respect to the vehicle body 2. As shown in FIGS. 1 and 2, the traveling device 3 includes front wheels 3F as front traveling devices respectively provided on the left and right at the front part of the vehicle body 2, and rear wheels 3R as rear traveling devices respectively provided on the left and right at the rear part of the vehicle body 2. Note that, among the traveling devices 3, either one or both of the front wheels 3F and the rear wheels 3R may be crawlers.

[0028] The main prime mover 5 is provided at the upper front part of the vehicle body 2 and is housed inside the bonnet 2A. The main prime mover 5 of the present embodiment is a diesel engine. Note that the main prime mover 5 may be a gasoline engine, or may be a hydrogen engine driven by the combustion energy of hydrogen gas. Alternatively, the main prime mover 5 may be an electric motor driven by electric power generated by a fuel cell or electric power charged in the battery 8 from an external power source, or may be a hybrid prime mover configured by combining an engine and an electric motor.

[0029] Note that an alternator is connected to the main prime mover 5 of the present embodiment. The alternator is connected to the drive shaft of the main prime mover 5 via a power transmission belt, and is rotationally driven by the power of the main prime mover 5 to generate electricity. Also, the electricity generated by the alternator is supplied to the battery 8 by an isolator.

[0030] The moving mechanism 80 supports the coupling device 6 at the rear part of the vehicle body 2 so as to be movable in the left-right direction. Details of the coupling device 6 will be described later. The moving mechanism 80 of the present embodiment is an actuator that moves the coupling device 6 in the left-right direction of the vehicle body 2. As shown in FIG. 3, the moving mechanism 80 includes a base portion 81, a rail 82, a slider 83, and a slider driving device 84. The slider driving device 84 includes a power transmission shaft 85 and a drive motor 86.

[0031] As shown in FIGS. 1 and 2, the base portion 81 is a frame that supports the rail 82 and is connected and supported at the rear part of the vehicle body 2. The base portion 81 extends from the rear part of the vehicle body 2 to a position behind the rear wheel 3R. The rail 82 is a frame that guides the slider 83 in its extending direction and extends in the left-right direction at the rear end portion of the base portion 81. That is, the rail 82 is disposed behind the rear wheel (rear traveling device) 4R.

[0032] As shown in FIG. 2, the rail 82 extends in the left-right direction orthogonal to the vehicle body center line CL1 that extends in the front-rear direction (traveling direction) of the vehicle body 2 passing through the center in the left-right direction (width direction). The rail 82 is formed to have a length L1 shorter than the outer width W1 of the rear wheels 3R provided on the left and right of the vehicle body 2. It is formed.

[0033] The slider 83 is a pedestal that supports the coupling device 6 and is movably connected to the rail 82 in its extending direction. That is, the slider 83 supports the coupling device 6 so as to be movable in the left-right direction within a range inside the outer width W1 of the left and right rear wheels 3R.

[0034] As shown in FIG. 3, the slider driving device 84 is a device that moves the slider 83 along the rail 82. The power transmission shaft 85 is a ball screw shaft that transmits the power of the drive motor 86 to the slider 83, extends parallel to the rail 82, and is inserted through the slider 83. The power transmission shaft 85 is connected to the drive shaft of the drive motor 86.

[0035] The drive motor 86 is an electric motor that rotationally drives the power transmission shaft 85, and is driven by receiving power supply from the vehicle body 2. Therefore, if the drive shaft of the drive motor 86 is rotationally driven, the power transmission shaft 85 will also be rotationally driven accordingly. As a result, the slider 83 slides within its extension range along the rail 82. Thereby, the position of the connecting device 6 moves in the left - right direction.

[0036] Thus, according to the work vehicle 1 of the present embodiment, since the connecting device 6 can be arbitrarily moved in the left - right direction, when connecting the work device U1 to the vehicle body 2, even if the position of the driven shaft US of the work device U1 with respect to the drive shaft 7S of the sub - prime mover 7 is shifted left and right, the position of the sub - prime mover 7 can be adjusted left and right. Therefore, the work device U1 can be smoothly connected to the sub - prime mover 7.

[0037] The connecting device 6 is a device for connecting the work device (implement) U1 to the vehicle body 2. As shown in FIGS. 1 and 2, the connecting device 6 of the present embodiment is connected to the rear part of the vehicle body 2 via the moving mechanism 80. The connecting device 6 of the present embodiment is provided on the slider 83 of the moving mechanism 80. Incidentally, the work vehicle 1 of the present embodiment can be used by appropriately replacing the work device U1 having various uses and functions such as a mower, a cultivator, a sprayer, a seeder, etc. with the connecting device 6.

[0038] As shown in FIGS. 1 - 4, the connecting device 6 has a lift arm 11, a lower link 12, a top link 13, a lift rod 14, a lift cylinder 15, and a hitch frame 16. Also, as shown in FIG. 1, the connecting device 6 has a suspension device 17. The connecting device has a prime mover (hereinafter referred to as a sub - prime mover) 7 that drives the work device U1. In the present embodiment, the sub - prime mover 7 is an electric motor that is driven using the electricity stored in the battery 8 as power.

[0039] As shown in FIG. 2, the lift arm 11, the lower link 12, the lift rod 14, and the lift cylinder 15 are all provided on the left and right sides sandwiching the virtual line VC that divides the slider 83 into left and right parts in the left - right direction with the virtual line VC as a reference.

[0040] The lift arm 11, the lower link 12, and the top link 13 are all frames that are long in one direction and are each pivotally supported at the rear part of the slider 83 so as to be swingable. Specifically, as shown in FIG. 4, the lift arm 11 has a first end portion 21 pivotally connected to an arm support shaft 2N extending in the left-right direction at the rear part of the slider 83 so as to be rotatable about the arm support shaft 2N. On the other hand, the second end portion 22 of the lift arm 11 is connected to the lift rod 14. The lift arm 11 extends rearward from the arm support shaft 2N.

[0041] The lower link 12 has a first end portion 23 pivotally connected to the lower part of the slider 83 so as to be rotatable about an axis extending in the left-right direction thereof. On the other hand, the second end portion 24 of the lower link 12 is connected to the hitch frame 16. The lower link 12 extends rearward from the lower part of the slider 83. and extends rearward.

[0042] The top link 13 has a first end portion 25 pivotally connected to the upper part of the slider 83 so as to be rotatable about an axis extending in the left-right direction thereof. On the other hand, the second end portion 26 of the top link 13 is connected to the hitch frame 16.

[0043] The lift rod 14 connects the lift arm 11 and the lower link 12 on the same left and right side. Specifically, the lift rod 14 has a first end portion 27 pivotally connected to the second end portion 22 of the lift arm 11 so as to be rotatable about an axis extending in the left-right direction thereof. On the other hand, the second end portion 28 of the lift rod 14 is pivotally connected to the middle portion between both end portions 23 and 24 of the lower link 12 so as to be rotatable about an axis extending in the left-right direction thereof. The lift rod 14 extends between the lift arm 11 and the lower link 12 on the same left and right side.

[0044] A joint 29 is provided at each of the second end 24 of the left lower link 12, the second end 24 of the right lower link 12, and the second end 26 of the top link 13. The hitch frame 16 is removably connected to these three joints 29. That is, as shown in FIGS. 1 and 2, the connecting device 6 of the present embodiment supports the hitch frame 16 by a link mechanism 30 composed of three links, namely, the left and right lower links 12 and the top link 13 disposed above the center between the left and right. Further, the working device U1 used by being connected to the work vehicle 1 of the present embodiment has, for example, one engaging portion at the upper position and two left and right engaging portions at the lower position on the work vehicle 1 side, and is connected to the hitch frame 16 by these three engaging portions. Details of the hitch frame 16 will be described later.

[0045] The lift cylinder 15 of the present embodiment is a hydraulic cylinder that expands and contracts in its extending direction by hydraulic pressure, and connects the lift arms 11 and the slider 83 on the same side on the left and right. Specifically, as shown in FIG. 4, the lift cylinder 15 is rotatably connected at its first end 31 between both ends 21 and 22 (intermediate portion) of the lift arm 11 about an axis extending in the left-right direction. On the other hand, the second end 32 of the lift cylinder 15 is rotatably connected to the rear portion of the slider 83 about an axis extending in the left-right direction.

[0046] Therefore, when the lift cylinder 15 is extended, the lift arm 11 swings upward with the first end 21 as a fulcrum, pulling up the lift rod 14. As a result, the lower link 12 is pulled up in conjunction and swings upward with the first end 23 as a fulcrum. On the other hand, when the lift cylinder 15 is shortened, the lift arm 11 swings downward with the first end 21 as a fulcrum, pulling down the lift rod 14. Accordingly, the lower link 12 is also pulled down in conjunction and swings downward with the first end 23 as a fulcrum. In this way, the connecting device 6 swings the lower link 12 up and down by the lift cylinder 15.

[0047] Still, the top link 13 has its first end 25 pivotally connected to the slider 83. Also, the second end 26 of the top link 13 is connected to the hitch frame 16 together with the second end 24 of the lower link 12. That is, the second end 26 of the top link 13 and the second end 24 of the lower link 12 are connected via the hitch frame 16. Therefore, when the lower link 12 is swung up and down as described above, the top link 13 also swings up and down accordingly. The hitch frame 16 is supported so as to be vertically movable with respect to the link mechanism 30 composed of these three links 12 and 13.

[0048] The lift cylinder 15 is connected to a hydraulic pump mounted on the vehicle body 2 through a hydraulic circuit and is operationally controlled by a control device of the vehicle body 2. The left and right lift cylinders 15 can be independently operationally controlled. Still, the lift cylinder 15 may be an electric cylinder driven by electric power supplied from the vehicle body 2.

[0049] As shown in FIGS. 5 and 6, the hitch frame 16 has a frame body 41, an upper connecting portion 42, a lower connecting portion 43, a bracket 44, and a protective member 45. The frame body 41 is formed of a metal material mainly containing iron. The frame body 41 has a main frame portion 46, a middle cross member portion 47, and an auxiliary frame portion 48.

[0050] The main frame portion 46, the middle cross member portion 47, and the auxiliary frame portion 48 are all formed of a square pipe, a round pipe, a flat bar, or the like. The main frame portion 46 is curved in an arch shape. Specifically, the main frame portion 46 has a substantially arc-shaped curvature with the central portion 46C in the left-right direction convex upward, and both side portions 46S in the left-right direction are continuously extended obliquely downward and outward from the central portion 46C. The middle cross member portion 47 extends in the left-right direction at a substantially central position in the up-down direction of the main frame portion 46 and connects the left and right side portions 46S to each other.

[0051] The auxiliary frame portion 48 is formed by being bent into a substantially L shape, and is respectively arranged at the left and right lower end portions of the main frame portion 46 with a space therebetween in the left-right direction. Specifically, the auxiliary frame portion 48 has a lower portion 48U formed by extending from the lower end portion of the side portion 46S of the main frame portion 46 toward the central side in the left-right direction, and an inner portion 48S formed by extending upward from the end portion on the central side in the left-right direction of the lower portion 48U. The upper end of the inner portion 48S of the auxiliary frame portion 48 is connected to the middle cross member portion 47. The inner portions 48S of the left and right auxiliary frame portions 48 are arranged substantially parallel to each other with a predetermined space therebetween in the left-right direction. The bracket 44 is arranged between these left and right inner portions 48S. Details of the bracket 44 will be described later.

[0052] The upper connection portion 42 is provided at the central portion 46C of the main frame portion 46. The upper connection portion 42 has a first link portion 51 and a first hook portion 52. The first link portion 51 is provided at the upper part of the upper connection portion 42 and pivotally supports the second end portion 26 of the top link 13. The first hook portion 52 is provided at the rear part of the upper connection portion 42 and engages and holds the upper engagement portion of the working device U1. The first hook portion 52 of the present embodiment is provided at two positions, upper and lower, at the rear part of the upper connection portion 42. Therefore, the working device U1 can engage the upper engagement portion with different heights with respect to the hitch frame 16. Note that the first hook portion 52 may be provided only at one position at the rear part of the upper connection portion 42.

[0053] The lower connection portion 43 is respectively provided at the lower end portions of the left and right side portions 46S of the main frame portion 46. Each of the left and right lower connection portions 43 has a second link portion 53 and a second hook portion 54. The second link portion 53 is provided at the outer portion of the lower connection portion 43 and pivotally supports the second end portion 24 of the lower link 12. The second hook portion 54 is provided at the rear part of the lower connection portion 43 and engages and holds the lower engagement portion of the working device U1.

[0054] The bracket 44 is a plate body that serves as an attachment portion for the sub prime mover 7, and is provided between the inner portions 48S of the left and right auxiliary frame portions 48. The bracket 44 is formed of a metal material mainly containing iron. The bracket 44 has a substrate portion 55, a side end plate portion 56, a support shaft portion 57, a motor receiving frame portion 58, and a shaft connection portion 59.

[0055] As shown in FIGS. 6 and 7, the substrate portion 55 has a through hole 60. The through hole 60 is provided at the center between the left and right sides of the substrate portion 55. The shaft connection portion 59 is inserted into the through hole 60 from the front (the back side of the through hole 60 when viewed from the rear of the vehicle body 2).

[0056] The side end plate portions 56 are respectively bent rearward at the left and right ends of the substrate portion 55. The support shaft portions 57 are formed to protrude outward in the left - right direction from the outer surfaces in the left - right direction of the side end plate portions 56, and are pivotally supported by the inner portion 48S of the auxiliary frame portion 48 of the frame body 41. In this way, the bracket 44 is supported rotatably with respect to the frame body 41 with the left and right support shaft portions 57 as fulcrums.

[0057] The motor receiving frame portion 58 is formed to extend outward in the left - right direction from the substrate portion 55. The sub - prime mover 7 is fixed to these left and right motor receiving frame portions 58. The shaft connection portion 59 is a shaft coupling having a first connection portion 67 and a second connection portion 68. The first connection portion 67 is connected and held in a non - rotatable state to the drive shaft 7S of the sub - prime mover 7. On the other hand, the second connection portion 68 has a hole shape that can be fitted in a non - rotatable state to the driven shaft US of the working device U1, and transmits power in a fitted state to the driven shaft US. Therefore, if the drive shaft 7S of the sub - prime mover 7 is rotationally driven, the driven shaft US of the working device U1 is also rotationally driven accordingly. In this way, the drive shaft 7S of the sub - prime mover 7 is directly connected to the driven shaft US of the working device U1 so as to be able to transmit power.

[0058] As described above, the sub - prime mover 7 is an electric motor that is driven by receiving power supply from the vehicle body 2. As shown in FIGS. 7 and 8, the sub - prime mover 7 has a housing 70 and a drive shaft 7S. Incidentally, if the sub - prime mover 7 is small and lightweight, it may be a gasoline engine or a hydraulic motor.

[0059] The housing 70 is formed of a metal material mainly containing iron. The housing 70 has a mounting frame portion 71 and a suspension portion 72. The housing 70 is formed in a substantially cylindrical shape and rotatably holds the drive shaft 7S therein. The mounting frame portion 71 is provided at the first end of the housing 70 and is fixed by bolts or the like in a state of facing the substrate portion 55 of the bracket 44. That is, the housing 70 is closely connected to the bracket 44. The drive shaft 7S is provided protruding from the mounting frame portion 71.

[0060] In this way, since the auxiliary prime mover 7 is swingably supported with respect to the frame body 41, the angle when connecting the driven shaft US of the working device U1 to the drive shaft 7S of the auxiliary prime mover 7 can be arbitrarily adjusted. Note that the mounting frame portion 71 may be configured separately from the housing 70 or may be integrally formed with the housing 70.

[0061] The suspension portion 72 is provided at the upper outer periphery of the housing 70 as a connecting portion for connecting and holding the suspension device 17. The suspension portion 72 of the present embodiment is provided at the upper outer periphery of the end portion of the housing 70 opposite to the mounting frame portion 71. Note that the suspension portion 72 may be configured separately from the housing 70 or may be integrally formed with the housing 70. Details of the suspension device 17 will be described later.

[0062] The protection member 45 is provided along the outer surface of the housing 70. Specifically, the protection member 45 is provided at a position in contact with both the mounting frame portion 71 of the housing 70 and the motor receiving frame portion 58 of the bracket 44. In the present embodiment, the protection member 45 is provided along the joint portion (around the mating surface) with the motor receiving frame portion 58 at the lower outer side of the housing 70.

[0063] The protection member 45 is a member formed of a metal material having a greater ionization tendency than the base material of the bracket 44, that is, a metal material mainly containing a sacrificial anode material. For example, in the present embodiment, while the bracket 44 is formed of a metal material mainly containing iron, the protection member 45 is formed of a metal material mainly containing zinc or aluminum.

[0064] The protective member 45 is detachably attached to the bracket 44 by bolts or the like. Therefore, when the sacrificial corrosion of the protective member 45 progresses, it can be appropriately replaced with a new protective member 45. Incidentally, if the protective member 45 is provided at a position in contact with both the housing 70 and the bracket 44, it may be detachably attached to the housing 70, or may be detachably attached to other parts. Further, a plurality of the protective members 45 may be arranged side by side so as to be in contact with the entire circumference of the joint portion between the housing 70 and the bracket 44.

[0065] As shown in FIG. 8, the suspension device 17 is connected between the hitch frame 16 and the auxiliary prime mover 7, and suspends and supports the auxiliary prime mover 7 so as to be swingable with respect to the hitch frame 16. The suspension device 17 of the present embodiment is a tension coil spring. Incidentally, the suspension device 17 may be a compression coil spring or a leaf spring as long as it can suspend and support the auxiliary prime mover 7 with respect to the hitch frame 16 in a stable posture. Alternatively, the suspension device 17 may be an air damper or a hydraulic damper.

[0066] The suspension device 17 has a first end portion 17A and a second end portion 17B. The first end portion 17A is connected to the rear portion of the upper connecting portion 42 of the hitch frame 16. On the other hand, the second end portion 17B is connected to a suspension portion 72 provided on the outer peripheral upper portion of the housing 70 of the auxiliary prime mover 7. That is, the second end portion 17B is connected to a position away from the swing center CL2 of the bracket 44 in the direction of the axis CL3 of the drive shaft 7S on the outer peripheral upper portion of the housing 70. Therefore, the auxiliary prime mover 7 is supported at three different points of the swing center CL2 of the bracket 44, a position away from the swing center CL2 in the direction of the axis CL3 of the drive shaft 7S, and the upper connecting portion 42 of the hitch frame 16 (three points located at the respective vertices of a virtual triangle).

[0067] The suspension device 17 expands and contracts elastically in the direction between the first end portion 17A and the second end portion 17B. Therefore, when an external force is applied to the auxiliary prime mover 7 in the swinging direction due to its own weight, vibrations during traveling, etc., the suspension device 17 applies a tensile force (restoring force against elongation) that resists the external force to the auxiliary prime mover 7. As a result, the auxiliary prime mover 7 is held in a stable suspended posture with respect to the hitch frame 16, and the load applied to the connecting portion between the drive shaft 7S of the auxiliary prime mover 7 and the driven shaft US of the working device U1 is also absorbed.

[0068] <Modification example> In addition, in the work vehicle 1 of the above embodiment, the drive shaft 7S of the auxiliary prime mover 7 is connected to the driven shaft US of the working device U1 via the coupling 66, but it may be configured to be directly connected to the drive shaft 7S of the auxiliary prime mover 7.

[0069] Specifically, the drive shaft 7S of the auxiliary prime mover 7 may be a hollow shaft, and a shaft connection portion may be integrally formed at its tip. On the other hand, the driven shaft US of the working device U1 is a shaft body that can be fitted into the shaft connection portion (inside the hollow shaft). The shaft connection portion has a hole shape that can fit the driven shaft US of the working device U1 in a non-rotating state, and power is transmitted in a fitted state with respect to the driven shaft US.

[0070] Alternatively, the driven shaft US of the working device U1 may be a hollow shaft, and a shaft connection portion may be provided at its tip. On the other hand, the drive shaft 7S of the auxiliary prime mover 7 is a shaft body that can be fitted into the shaft connection portion (inside the hollow shaft). The shaft connection portion has a hole shape that can fit the drive shaft 7S of the auxiliary prime mover 7 in a non-rotating state, and power is transmitted in a fitted state with respect to the drive shaft 7S. Also in this case, the same operational effects as those of the work vehicle 1 of the above embodiment are achieved.

[0071] Further, in the work vehicle 1 of the above embodiment, the connecting device 6 is attached to the rear portion of the vehicle body 2, but the connecting device 6 may be attached to the front portion of the vehicle body 2. Also in this work vehicle 1, if the bracket 44 is connected to the hitch frame 16 so as to be swingable about an axis CL2 extending in the left-right direction (width direction) of the vehicle body 2, the working device U1 can be smoothly connected to the vehicle body 2.

[0072] In the work vehicle 1 of the above embodiment, when the auxiliary prime mover 7 swings, the angle when connecting the driven shaft US of the work device U1 to the drive shaft 7S of the auxiliary prime mover 7 can be arbitrarily adjusted. However, a universal joint may be provided on the drive shaft 7S of the auxiliary prime mover 7 so that the angle when connecting the drive shaft 7S to the driven shaft US by the universal joint 75 can be arbitrarily adjusted. As a result, since the drive shaft 7S of the auxiliary prime mover 7 is connected to be able to transmit power indirectly to the driven shaft US of the work device U1, it exhibits the same operational effects as the work vehicle 1 of the above embodiment. Since the drive shaft 7S of the auxiliary prime mover 7 is connected to be able to transmit power indirectly to the driven shaft US of the work device U1, it exhibits the same operational effects as the work vehicle 1 of the above embodiment.

[0073] The present invention provides a work vehicle 1 described in the following items.

[0074] (Item A1) A work vehicle 1 comprising: a travelable vehicle body 2; a connecting device 6 having a driven shaft US to which power is input and connected to a work device U1 driven by the power input to the driven shaft US, the connecting device 6 being attached to the vehicle body 2; and the connecting device 6 having a prime mover 7 having a drive shaft 7S that outputs power, the drive shaft 7S of the prime mover 7 being directly or indirectly connected to the driven shaft U7 of the work device U1 so as to be able to transmit power.

[0075] According to the work vehicle 1 according to this Item A1, the work device U1 can be efficiently driven by the power of the work prime mover 7 provided in the connecting device 6, and the driving load on the power source on the vehicle body 2 side is also reduced, so workability is improved.

[0076] (Item A2) The work vehicle 1 according to Item A1, wherein the prime mover 7 is an electric motor driven by receiving power supply from the vehicle body 2.

[0077] According to the work vehicle 1 according to this Item A2, since the prime mover 7 has a higher energy conversion efficiency than those with a gasoline engine or a hydraulic motor, the work device U1 can be driven more efficiently. Therefore, the workability is further improved accordingly.

[0078] (Item A3) The connection device 6 includes a link mechanism 30 pivotally supported by the vehicle body 2, and a hitch frame 16 connected to the link mechanism 30 and to which the working device U1 is connected. The hitch frame 16 includes a bracket 44 to which the prime mover 7 is attached. The work vehicle 1 according to Item A1 or A2 as described above.

[0079] According to the work vehicle 1 according to this Item A3, since the prime mover 7 can be disposed in the vicinity of the working device U1 connected to the hitch frame 16, it is possible to more efficiently output the power of the prime mover 7 to the working device U1. Therefore, the workability is further improved.

[0080] (Item A4) The connection device 6 is attached to the front part or the rear part of the vehicle body 2 in the traveling direction. The bracket 44 is swingably connected to the hitch frame 16 about an axis CL2 extending in the vehicle width direction of the vehicle body 2. The work vehicle 1 according to Item A3 as described above.

[0081] According to the work vehicle 1 according to this Item A4, since the load applied to the connection part between the drive shaft 7S of the prime mover 7 and the driven shaft US of the working device U1 during traveling is dispersed by the swinging of the bracket 44 about the axis CL2, it is possible to more efficiently output the power of the prime mover 7 to the working device U1. Therefore, the workability is further improved.

[0082] (Item A5) The connection device 6 has a suspension device 17 that swingably suspends and supports the prime mover 7 on the hitch frame 16. The work vehicle 1 according to Item A4 as described above.

[0083] According to the work vehicle 1 according to this Item A5, since the posture of the prime mover 7 suspended and supported by the hitch frame 16 can be stabilized by the suspension device 17, it is possible to more efficiently output the power of the prime mover 7 to the working device U1. Therefore, the workability is further improved.

[0084] (Item A6) The suspension device 17 has a first end portion 17A and a second end portion 17B on the opposite side of the first end portion 17A. The first end portion 17A is connected to the upper portion of the hitch frame 16, and the second end portion 17B is connected to a position away from the axis CL3 of the drive shaft 7S in the direction from the swing center CL2 of the bracket 44 in the prime mover 7. The work vehicle 1 according to Item A5.

[0085] According to the work vehicle 1 according to this Item A6, since the prime mover 7 can be supported at three different points: the swing center CL2 of the bracket 44, a position away from the swing center CL2 in the direction of the axis CL3 of the drive shaft 7S, and the upper portion of the hitch frame 16, the suspension posture of the prime mover 7 becomes more stable. As a result, it becomes possible to output the power of the prime mover 7 to the work device U1 more efficiently. Therefore, the workability is further improved.

[0086] (Item A7) The suspension device 17 is a spring member that applies a predetermined tensile force upward to the prime mover 7. The work vehicle 1 according to Item A5.

[0087] According to the work vehicle 1 according to this Item A7, since the elastic force of the suspension device 17 absorbs the load applied to the connection portion between the drive shaft 7S of the prime mover 7 and the driven shaft US of the work device U1 during traveling and the like, it becomes possible to output the power of the prime mover 7 to the work device U1 more efficiently. Therefore, the workability is further improved.

[0088] (Item A8) The drive shaft 7S of the prime mover 7 is engageable with the driven shaft US of the work device U1 and can transmit power in the engaged state. The work vehicle 1 according to Item A1.

[0089] According to the work vehicle 1 according to this Item A8, since the power of the prime mover 7 can be directly transmitted to the driven shaft US of the work device U1, it becomes possible to output the power of the prime mover 7 to the work device U1 more efficiently. Therefore, the workability is further improved.

[0090] (Item A9) Either one of the drive shaft 7S of the prime mover 7 or the driven shaft US of the working device U1 is a hollow shaft, and the other of the drive shaft 7S of the prime mover 7 or the driven shaft US of the working device U1 is a shaft body that can be inserted into the hollow shaft. The work vehicle 1 according to Item A8

[0091] According to the work vehicle 1 according to this Item A9, since the power of the prime mover 7 can be directly transmitted to the driven shaft US of the working device U1, it is possible to more efficiently output the power of the prime mover 7 to the working device U1. Therefore, the workability is further improved.

[0092] (Item A10) The connecting device 6 has a universal joint 75 that can swingably connect the driven shaft US of the working device U1 to the drive shaft 7S of the prime mover 7. The work vehicle 1 according to Item A1 or A2

[0093] According to the work vehicle 1 according to this Item A10, when the universal joint 75 bends, the load applied to the connection part between the drive shaft 7S of the prime mover 7 and the driven shaft US of the working device U1 during traveling is absorbed Therefore, it is possible to more efficiently output the power of the prime mover 7 to the working device U1. Therefore, the workability is further improved.

[0094] (Item A11) The prime mover 7 has a housing 70 that holds the drive shaft 7S, and the bracket 44 has a protective member 45 formed of a metal material with a greater ionization tendency than the base material of the bracket 44. The protective member 45 is provided in contact with both the housing 70 and the bracket 44. The work vehicle 1 according to Item A3

[0095] The joint part between the housing 70 and the bracket 44 is likely to accumulate rainwater and water scattered from the road surface during work. If water remains in the joint part for a long time, there is a risk that the housing 70 and the bracket 44 will emit electrons and become cationized, accelerating the progress of corrosion.

[0096] However, according to the work vehicle 1 related to this item A11, even if water adheres and stays on the joint part, the protection member 45 emits electrons and is cationized prior to the housing 70 and the bracket 44, and sacrificially corrodes. Thereby, it becomes possible to delay the occurrence of corrosion at the joint part. Therefore, stable performance can be exhibited over a long period of time.

[0097] (Item A12) The work vehicle 1 according to item A11, wherein the protection member 45 is removably connected to the housing 70 or the bracket 44.

[0098] According to the work vehicle 1 related to this item A12, even if the sacrificial corrosion of the protection member 45 progresses as described above, it can be appropriately replaced with a new protection member 45, so that more stable performance can be exhibited over a long period of time.

[0099] (Item A13) The work vehicle 1 according to item A11, wherein the housing 70 is closely connected to the bracket 44, and the protection member 45 is disposed below the housing 70.

[0100] Water flowing down from the surroundings tends to collect and relatively stay below the part where the housing 70 and the bracket 44 are closely connected. Therefore, corrosion is likely to occur accordingly. However, according to the work vehicle 1 related to this item A13, since the protection member 45 is provided below the part where the housing 70 and the bracket 44 are closely connected, it becomes possible to delay the occurrence of corrosion at the close part. Therefore, stable performance can be exhibited over a long period of time.

[0101] (Item B1) A work vehicle 1 including a travelable vehicle body 2, a connecting device 6 to which a working device U1 is connected, and a moving mechanism 80 attached to the vehicle body 2, the moving mechanism 80 connecting and supporting the connecting device 6 so as to be movable in the width direction of the vehicle body 2.

[0102] According to the work vehicle 1 related to this item B1, since the connecting device 6 can be moved in the left - right direction (width direction) of the vehicle body 2 in accordance with the target work position, workability is improved. Further, according to the work vehicle 1 related to this item B1, when connecting the vehicle body 2 and the work device U1, even if the positional relationship between the vehicle body 2 and the work device U1 is slightly deviated in the width direction, the connecting device 6 can be moved in the width direction in accordance with the deviation, so the workability is further improved.

[0103] (Item B2) The moving mechanism 80 includes a rail 82 extending in the width direction, a slider 83 movably connected to the rail 82 in the width direction, and a slider driving device 84 for moving the slider 83 along the rail 82. The connecting device 6 is provided on the slider 83 in the work vehicle 1 described in item B1. According to the work vehicle 1 related to this item B2, since the connecting device 6 can be moved more smoothly in the width direction, workability is further improved.

[0104] According to the work vehicle 1 related to this item B2, since the connecting device 6 can be moved more smoothly in the width direction, workability is further improved.

[0105] (Item B3) The rail 82 extends in the width direction perpendicular to the vehicle body center line CL3 that passes through the center in the width direction and extends in the traveling direction of the vehicle body 2 in the work vehicle 1 described in item B2.

[0106] According to the work vehicle 1 related to this item B3, since the connecting device 6 can be accurately moved in the width direction of the vehicle body 2, workability is further improved.

[0107] (Item B4) The work vehicle 1 includes a traveling device 3 that supports the vehicle body 2 so as to be travelable. The traveling device 3 includes a front traveling device 3F disposed at the front of the vehicle body 2 in the traveling direction and a rear traveling device 3R disposed at the rear of the vehicle body 2 in the traveling direction. The rail 82 is disposed behind the rear traveling device 3R in the work vehicle 1 described in item B2.

[0108] According to the work vehicle 1 related to this item B4, when moving the connecting device 6 in the width direction of the vehicle body 2, it is difficult for the connecting device 6 to contact the rear traveling device 3R of the vehicle body 2, so the workability is further improved.

[0109] (Item B5) The work vehicle 1 according to any one of Items B2 to B4, wherein the connecting device 6 has a prime mover 7 that drives the work device U1.

[0110] According to the work vehicle 1 related to this item B5, the work device U1 can be efficiently driven by the power of the prime mover 7 provided in the connecting device 6, and the driving load of the power source on the vehicle body 2 side is also reduced, so the workability is further improved.

[0111] (Item B6) The work vehicle 1 according to Item B5, wherein the prime mover 7 is an electric motor that is driven by receiving power supply from the vehicle body 2.

[0112] According to the work vehicle 1 related to this item B6, since the energy conversion efficiency is high compared to those in which the prime mover 7 is a gasoline engine or a hydraulic motor, the work device U1 can be driven more efficiently. Therefore, the workability is further improved accordingly.

[0113] (Item B7) The work vehicle 1 according to Item B5, wherein the connecting device 6 has a link mechanism 30 pivotally supported at the rear of the slider 83, and a hitch frame 16 that is connected to the link mechanism 30 and connects the work device U1, and the prime mover 7 is provided on the hitch frame 16.

[0114] According to the work vehicle 1 related to this item B7, since the prime mover 7 can be arranged in the vicinity of the work device U1 connected to the hitch frame 16, it is possible to output the power of the prime mover 7 to the work device U1 more efficiently. Therefore, the workability is further improved.

[0115] (Item B8) The working vehicle 1 according to item B5, wherein the prime mover 7 is disposed on the rear extension line CL4 at the center in the width direction of the slider 83.

[0116] According to the working vehicle 1 according to this item B8, since the relatively heavy prime mover 7 is disposed on the rear extension line at the center in the width direction of the slider 83, the slider 83 can be stably moved in the width direction, and the workability is further improved.

[0117] As described above, the present invention has been described. However, the embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and it is intended that all modifications within the meaning and scope equivalent to the claims are included.

Explanation of reference numerals

[0118] 1 Working vehicle 2 Vehicle body 2A Bonnet 2B Cabin 3 Travel device 3F Front wheel (front travel device) 3R Rear wheel (rear travel device) 4 Driver's seat 5 Main prime mover 6 Link device 7 Sub-prime mover (prime mover) 7S Drive shaft 11 Lift arm 12 Lower link 13 Top link 14 Lift rod 15 Lift cylinder 16 Hitch frame 17 Suspension device 17A First end 17B Second end 30 Link mechanism 44 Bracket 45 Protection member 70 Housing 75 Universal joint 80 Moving mechanism 81 Base portion 82 Rail 83 Slider 84 Slider drive device 85 Power transmission shaft 86 Drive motor CL2 Swing center CL3 Axis of drive shaft U1 Working device US Driven shaft

Claims

1. A work vehicle comprising: a travelable vehicle body; a coupling device having a driven shaft to which power is input and a working device driven by the power input to the driven shaft, the coupling device being attached to the vehicle body; the coupling device having a prime mover having a drive shaft that outputs power; the drive shaft of the prime mover being directly or indirectly connected to the driven shaft of the working device so as to be capable of power transmission.

2. The work vehicle according to claim 1, wherein the prime mover is an electric motor that is driven by receiving power supply from the vehicle body.

3. The coupling device includes: a link mechanism pivotally supported by the vehicle body; a hitch frame connected to the link mechanism and to which the working device is connected; the work vehicle according to claim 1 or 2, wherein the hitch frame includes a bracket to which the prime mover is attached.

4. The coupling device is attached to a front portion or a rear portion of the vehicle body in a traveling direction of the vehicle body; the work vehicle according to claim 3, wherein the bracket is swingably connected to the hitch frame about an axis extending in a width direction of the vehicle body.

5. The work vehicle according to claim 4, wherein the coupling device has a suspension device that swingably suspends and supports the prime mover on the hitch frame.

6. The suspension device has a first end portion and a second end portion opposite to the first end portion; the first end portion is connected to an upper portion of the hitch frame; the work vehicle according to claim 5, wherein the second end portion is connected to a position away from an axis direction of the drive shaft from a swing center of the bracket in the prime mover.

7. The work vehicle according to claim 5, wherein the suspension device is a spring member that applies a predetermined tensile force upward to the prime mover.

8. The work vehicle according to claim 1, wherein the drive shaft of the prime mover is engageable with the driven shaft of the working device and is capable of power transmission in an engaged state.

9. Either one of the drive shaft of the prime mover or the driven shaft of the working device is a hollow shaft; the work vehicle according to claim 8, wherein the other of the drive shaft of the prime mover or the driven shaft of the working device is a shaft body that can be inserted into the shaft of the hollow shaft.

10. The work vehicle according to claim 1 or 2, wherein the coupling device has a universal joint that can swingably connect the driven shaft of the working device to the drive shaft of the prime mover.

11. The prime mover has a housing that holds the drive shaft. The bracket has a protective member formed of a metal material having a greater ionization tendency than the base material of the bracket. The work vehicle according to claim 3, wherein the protective member is provided in contact with both the housing and the bracket.

12. The work vehicle according to claim 11, wherein the protective member is removably connected to the housing or the bracket.

13. The housing is closely connected to the bracket. The work vehicle according to claim 11, wherein the protective member is disposed below the housing.

Images