Work vehicles

Abstract

To provide a work vehicle capable of reducing a ground height and performing work in a state in which an implement used in a normal work vehicle, is attached to the work vehicle, for solving problems for example, for traveling under trees in a fruit garden or the like, a work vehicle to which wheels having a small tire diameter are attached and whose vehicle body is made low, is used, the work vehicle whose vehicle body is made low, comprises a PTO and an implement coupling link similar to a normal work vehicle, and various kinds of implements can be attached to the work vehicle, however, a fitting position is lower than a normal fitting position, angles formed when the implement is grounded, are varied, therefore a dedicated implement is required.SOLUTION: A work vehicle has a PTO shaft 6 for providing power to an outside from a transmission case 5 which transmits drive force to travel wheels 2, and a lifting link mechanism L for vertically moving an implement 4 is provided on a rear part of a travel vehicle body 1, a power transfer mechanism 50 is provided between the lifting link mechanism L and the implement 4 for outputting power input from the PTO shaft 6 at a position above a position where the power is input.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a work vehicle having a work implement attached to the rear. [Background technology]

[0002] In order to run under trees in orchards and the like, there are work vehicles in which the upper end of the tailpipe is lower than the traveling body and the body is lowered by fitting wheels with small tire diameters so that the upright tailpipe does not come into contact with tree branches during work (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6531692 Summary of the Invention [Problem to be solved by the invention]

[0004] Like normal work vehicles, low-body work vehicles are equipped with a PTO and implement connection link, and various implements can be attached to them. However, because the mounting position is lower than normal, the angle when the vehicle touches the ground is different, and special implements were required.

[0005] The present invention has been made in consideration of the above, and aims to provide a work vehicle with a low ground clearance that can be fitted with work equipment used in normal work vehicles and used for work. [Means for solving the problem]

[0006] The first invention relates to a traveling vehicle having a PTO shaft (6) that extracts power from a transmission case (5) that transmits driving force to traveling wheels (2) and a lifting link mechanism (L) that moves a working machine (4) up and down at the rear of a traveling body (1), and a power transfer mechanism (50) that outputs the power input from the PTO shaft (6) at a position higher than the position at which the power was input, between the lifting link mechanism (L) and the working machine (4), A connecting mechanism (3) is attached to the lifting link mechanism (L), a working machine (4) is detachably attached to the connecting mechanism (3), and a power transfer mechanism (50) is provided on the connecting mechanism (3); This work vehicle is characterized in that the connecting mechanism (3) is composed of a front mounting hitch (30) connected to the traveling vehicle body (1) side and a rear mounting hitch (40) connected to the work machine (4) side, and the rear hitch portion (44, 45) of the rear mounting hitch (40) is located higher than the front hitch portion (36, 37) of the front mounting hitch (30). The first invention related to the present inventionis a work vehicle having a PTO shaft 6 that extracts power from a transmission case 5 that transmits driving force to the traveling wheels 2, and a lifting link mechanism L that moves a work implement 4 up and down at the rear of the traveling body 1, and a power transfer mechanism 50 that outputs the power input from the PTO shaft 6 at a position higher than the position at which it was input, between the lifting link mechanism L and the work implement 4.

[0007] The first invention related to the present invention According to the invention, a power transfer mechanism 50 is provided between the lifting link mechanism L and the work machine 4, which outputs the power input from the PTO shaft 6 at a position higher than the position at which the power was input, so that a general-purpose work machine 4 that is not a dedicated product can be attached to a work vehicle with a low ground clearance.

[0008] The second invention related to the present invention The link mechanism 3 is attached to the lifting link mechanism L, and the working machine 4 is detachably attached to the link mechanism 3. The link mechanism 3 is provided with a power transfer mechanism 50. The first invention related to the present invention It is a work vehicle.

[0009] The second invention related to the present invention According to the above, a connecting mechanism 3 is attached to the lifting link mechanism L, and a working machine 4 is detachably attached to the connecting mechanism 3. In addition, a power transfer mechanism 50 is provided in the connecting mechanism 3, so that a general-purpose working machine 4 that is not a dedicated product can be easily attached to a work vehicle with a low ground clearance.

[0010] The third invention related to the present invention The connecting mechanism 3 is composed of a front mounting hitch 30 connected to the traveling vehicle body 1 side and a rear mounting hitch 40 connected to the working machine 4 side, and the rear hitch parts 44, 45 of the rear mounting hitch 40 are provided above the front hitch parts 36, 37 of the front mounting hitch 30. The second invention related to the present invention It is a work vehicle. [Brief description of the drawings]

[0011] [Figure 1] 1 is a side view showing a state in which a work implement is attached to the rear of a tractor according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a side view for explaining the operation of mounting a work implement to the rear of a tractor according to an embodiment of the present invention. [Diagram 3] FIG. 2 is a perspective view illustrating the operation of mounting a work implement to the rear of a tractor according to an embodiment of the present invention. [Figure 4] 1 is a side cross-sectional view of a main part of a tractor according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] A low-floor tractor (a tractor with small-diameter wheels to lower the vehicle body and set a low ground clearance so that it can travel under trees in orchards, etc.) will be described as one type of work vehicle shown as an example of an embodiment of the present invention. In the following, front, rear, left and right are referred to based on the forward direction of the vehicle body.

[0013] The tractor moves on left and right front wheels and left and right rear wheels 2 as running wheels, and a rotary tiller 4 as a working machine is detachably attached to the rear via a connecting mechanism 3.

[0014] The tractor's running body 1 receives the driving force of an engine mounted at the front, which is changed in a transmission case 5 and transmitted to the left and right front wheels and the left and right rear wheels 2 to rotate and move forward. The driving force is also branched in the transmission case 5 and transmitted to a PTO shaft 6, which outputs the driving force to the outside.

[0015] A hydraulic device (work equipment lifting device) 8 having left and right lift arms 7 is provided on a transmission case 5 at the rear of the traveling vehicle body 1, as well as left and right fenders 9 covering the left and right rear wheels 2. A driver's seat 10 is provided between the left and right fenders 9. A PTO shaft 6 protrudes rearward from the rear end of the transmission case 5. A universal joint on the base end side of a drive shaft 6a having universal joints on both ends is connected to the PTO shaft 6.

[0016] An upper link base 11 is fixed to the upper rear end of the running body 1 at the center position in the left-right direction of the body, and the base of an upper link 12 is pivoted to the rear end of the upper link base 11 so that it can rotate freely up and down. A ball joint 12a is provided at the tip of the upper link 12.

[0017] Left and right lower links 13 are pivotally supported at their bases on the lower rear end of the vehicle body 1 so as to be vertically rotatable, and the left and right lower links 13 are each provided at their tip with a ball joint 13a.

[0018] The middle parts of the left and right lower links 13 are connected to the left and right lift arms 7 by left and right lift rods 14, respectively, and the left and right lower links 13 are moved up and down by the vertical movement of the left and right lift arms 7 by the hydraulic device 8, thereby moving the rotary tiller 4 attached via the connecting mechanism 3 up and down. The upper links 12 and the left and right lower links 13 form a lifting link mechanism L.

[0019] In the rotary tiller 4, support arms 17 protrude on both sides from a gear case 16 from which an input shaft 15 with a spline formed at the tip protrudes forward, and a transmission case 18 and a side frame 19 are fixed to the outer ends of the left and right support arms 17 to form a rotary machine frame 20. A tine shaft is rotatably supported at the bottom of the transmission case 18 and the side frame 19, and a number of tilling tines are attached to this tine shaft to form a rotary tilling section 21. A tilling cover 22 is provided to cover the top, both sides and rear of the rotary tilling section 21.

[0020] An upper mast 23 is fixed to the gear case 16, and a pair of left and right connecting brackets 24 protruding forward are provided on the left and right support arms 17, one on each side.

[0021] An upper engagement portion 25 formed by a left-right pin is provided at the upper end of the upper mast 23. A pair of left and right lower engagement portions 26 formed by left-right pins are provided on the left and right connecting brackets 24.

[0022] The connecting mechanism 3 is composed of a standard mounting hitch 30 serving as a front mounting hitch for mounting a standard-specification work machine, and a conversion mounting hitch 40 serving as a rear mounting hitch.

[0023] The standard mounting hitch 30 is attached to the traveling body 1 by connecting the ball joint 12a at the tip of the upper link 12 with an upper link pin 33 to an engagement hole 32a of an upper mounting stay 32 on the traveling body 1 side provided at the upper central part of an inverted U-shaped standard hitch frame 31, and by connecting the ball joints 13a at the tips of the left and right lower links 13 with left and right lower link pins 34 provided on the left and right sides of the lower part of the standard hitch frame 31 with lower link pins 35, respectively.

[0024] The standard mounting hitch 30 has an upwardly concave standard upper connecting portion 36 that constitutes the front hitch portion at the upper center of the standard hitch frame 31, and left and right lower connecting portions 37 that constitute the front hitch portion on the left and right sides of the lower part of the standard hitch frame 31, thereby forming a typical quick hitch (one-touch hitch).

[0025] The left and right lower connecting parts 37 are composed of an upper engaging body 37a in the form of a downward hook fixed to the standard hitch frame 31 and an upward hook-shaped lower engaging body 37b whose base is pivoted on a pivot shaft and whose tip side rotates up and down. The lower engaging body 37b is biased by a biasing member in a direction in which the tip side rotates upward, and a guide cam surface is formed on the tip end surface. When a pin body (in this embodiment, the left and right engaging pins 43 of the conversion mounting hitch 40 described later)) comes into contact with the left and right lower connecting parts 37 from the rear, the lower engaging body 37b rotates downward by the guide cam surface, and the pin body is held by the upper engaging body 37a and the lower engaging body 37b. The held state is released when the release lever 38 is operated to rotate the lower engaging body 37b downward.

[0026] Further, a holder 39 for holding the universal joint on the tip side of the drive shaft 6a is provided at the center of the lower part of the standard hitch frame 31.

[0027] The converted mounting hitch 40 is attached to the rear of the standard mounting hitch 30 by engaging from above the mounting pin 42a of the upper mounting stay 42 provided at the upper central part of the inverted U-shaped converted hitch frame 41 with the recess of the standard upper connecting part 36 of the standard mounting hitch 30, and by engaging the left and right engagement pins 43 provided on the left and right sides of the lower part of the converted hitch frame 41 with the left and right lower connecting parts 37 of the standard mounting hitch 30.

[0028] The conversion mounting hitch 40 has an upwardly concave conversion upper connecting portion 44 that constitutes the rear hitch portion at the upper center of the conversion hitch frame 41, and left and right lower connecting portions 45 that constitute the rear hitch portion on the left and right sides of the lower part of the conversion hitch frame 41, thereby forming a typical quick hitch (one-touch hitch).

[0029] The left and right lower connecting parts 45 are composed of an upper engaging body 46a in the form of a downward hook fixed to the conversion hitch frame 41 and a lower engaging body 46b in the form of an upward hook whose base is pivoted on a pivot shaft and whose tip side rotates up and down. The lower engaging body 46b is biased by a biasing member in a direction in which the tip side rotates upward, and a guide cam surface is formed on the tip end surface. When the left and right lower engaging parts 26 of the rotary tiller 4, which is a pin body, come into contact with the left and right lower connecting parts 45 from the rear, the lower engaging body 46b rotates downward by the guide cam surface, and the left and right lower engaging parts 26 are held by the upper engaging body 46a and the lower engaging body 46b. This holding state is released when the release lever 47 is operated to rotate the lower engaging body 46b downward.

[0030] In addition, a power transfer mechanism 50 is provided in the center of the conversion hitch frame 41.

[0031] The power transfer mechanism 50 is composed of a transmission case 51 fixed to the conversion hitch frame 41, an input bevel gear 52 having an input shaft 52a which is rotatably supported by bearings at the bottom of the transmission case 51 and extends toward the front of the transmission case 51 and has a spline formed at the tip of the shaft, and an output bevel gear 53 which is rotatably supported by bearings at the top of the transmission case 51 and meshes with the input bevel gear 52.

[0032] A spline engagement hole 53a is formed in the axis of the output bevel gear 53, and the input shaft 15 of the rotary tiller 4 can be spline-engaged with the spline engagement hole 53a through a hole provided in the rear wall of the transmission case 51.

[0033] When the converted mounting hitch 40 is attached to the standard mounting hitch 30, the rear hitch portion consisting of the converted upper connecting portion 44 and the left and right lower connecting portions 45 of the converted mounting hitch 40 is configured to be positioned higher than the front hitch portion consisting of the standard upper connecting portion 36 and the left and right lower connecting portions 37 of the standard mounting hitch 30, so that the ground clearance of the rear hitch portion of the converted mounting hitch 40 is the same height as the hitch portion when the standard mounting hitch 30 is attached to a standard tractor.

[0034] In addition, the power transfer mechanism 50 can transmit the driving force of the drive shaft 6a, which is located at a lower position, to the input shaft 15 of the rotary tiller 4, which is located at a higher position, via the input bevel gear 52 and the output bevel gear 53 by spline-engaging the input shaft 52a with the universal joint at the tip of the drive shaft 6a.

[0035] The rotary tiller 4 is attached to the rear of the conversion mounting hitch 40 by engaging its upper engagement portion 25 from above with the recessed portion of the conversion upper connecting portion 44 of the conversion mounting hitch 40 and engaging the left and right lower engagement portions 26 with the left and right lower connecting portions 45, respectively, and the input shaft 15 is spline-engaged with the spline engagement hole 53a of the output bevel gear 53 of the power transfer mechanism 50 to input the driving force from the PTO shaft 6.

[0036] In summary, when the connecting mechanism 3 consisting of the standard mounting hitch 30 and the converted mounting hitch 40 is attached to a low-bed tractor, the rear hitch portion consisting of the converted upper connecting portion 44 and the left and right lower connecting portions 45 of the converted mounting hitch 40 of the connecting mechanism 3 will be at the same height as the hitch portion when the standard mounting hitch 30 is attached to a standard tractor with a standard ground clearance, and the driving force of the drive shaft 6a, which is at a low position due to the power transfer mechanism 50, will be at a high position when the standard mounting hitch 30 is attached to a standard tractor with a standard ground clearance, so that a standard rotary tiller 4 can be attached to a low-bed tractor and proper tilling work can be performed.

[0037] Therefore, a standard rotary tiller 4 that is attached to a standard tractor used in paddy fields and fields can be attached to a low-bed tractor and appropriate tilling work can be performed, so there is no need for a dedicated implement for the low-bed model, and an inexpensive agricultural work style can be realized.

[0038] In the above embodiment, an example has been shown in which the rotary tiller 4 is used as the working machine, but any other working machine such as a grass cutting machine may be used.

[0039] In addition, some working machines are only available in low-floor specifications, so when attaching a working machine with a low-floor specification to a tractor, it is sufficient to attach only the standard mounting hitch 30 to the low-floor specification tractor, attach the working machine with a low-floor specification to the standard mounting hitch 30, and perform work. [Explanation of symbols]

[0040] 1 Running vehicle 2 Running wheels (rear wheels) 3 Connection mechanism 4. Working machine (rotary tiller) 5 Transmission case 6 PTO shaft 30 Front mounting hitch (standard mounting hitch) 36 Front hitch (standard upper connection) 37 Front hitch section (lower left and right connection section) 40 Rear mounting hitch (conversion mounting hitch) 44 Rear hitch part (conversion upper connection part) 45 Rear hitch section (lower left and right connection section) 50 Power transfer mechanism L Lifting link mechanism

Claims

[Claim 1] A vehicle having a PTO shaft (6) that extracts power from a transmission case (5) that transmits driving force to running wheels (2) and a lifting link mechanism (L) that raises and lowers a work machine (4) at the rear of the running body (1), the vehicle having a power transfer mechanism (50) between the lifting link mechanism (L) and the work machine (4) that outputs the power input from the PTO shaft (6) at a position higher than the position at which it was input, A connecting mechanism (3) is attached to the lifting link mechanism (L), a working machine (4) is detachably attached to the connecting mechanism (3), and a power transfer mechanism (50) is provided on the connecting mechanism (3); This work vehicle is characterized in that the connecting mechanism (3) is composed of a front mounting hitch (30) connected to the traveling vehicle body (1) side and a rear mounting hitch (40) connected to the work machine (4) side, and the rear hitch portion (44, 45) of the rear mounting hitch (40) is provided above the front hitch portion (36, 37) of the front mounting hitch (30).

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