JP2002238307A - Compact working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact working vehicle by disposing various implements as much close to the vehicle body as possible and shortening the total length ranged from the front end of the vehicle body to the rear ends of the various implements. SOLUTION: The travel section is formed by attaching front and rear driven wheels to the front and rear ends, respectively, of a travel frame extended in the longitudinal direction, disposing a driving wheel at a place between the front and rear driven wheels and above the front and rear driven wheels, and winding a crawler belt on the wheels. On the side view, the rotation support point of a lift arm is disposed at a place just above the driving wheel, while the rotation support point of a lower link is disposed at a position just below the driving wheel. The various implements connected to the rear end portion of the lower link can be lifted with the lift arm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a small work vehicle.

[0002]

2. Description of the Related Art Conventionally, as one form of a small work vehicle, a body frame is erected between a pair of left and right crawler traveling parts.
There is a vehicle in which a prime mover unit and an operation unit are arranged on the vehicle body frame.

[0003] In the traveling section, a driven wheel is attached to a front end of a traveling frame extending in the front-rear direction, and a drive wheel is attached to a rear end of the traveling frame, and a crawler belt is wound between the driving wheels.

[0004] Various working devices are connected to the rear end of the vehicle body frame via a lifting mechanism, and the various working devices can be raised and lowered by the lifting mechanism.

[0005]

However, in the small work vehicle described above, the lifting mechanism is connected to the rear end of the body frame, and various working devices are connected to the rear end of the lifting mechanism. Various working devices are placed at a position far away from the vehicle body to the rear, and the total length from the front end of the vehicle body to the rear end of the various working devices is increased, and the center of gravity of the various working devices when moving up and down when moving back and forth is large. As a result, there is a problem that the vertical fluctuation of the front part of the vehicle body becomes large due to the influence.
Therefore, it is necessary to attach a large number of front weights to the front end of the vehicle body to reduce the vertical movement of the vehicle body.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a small work vehicle in which a body frame is provided between a pair of right and left crawler traveling parts, and a prime mover unit and an operation unit are disposed on the body frame. , The running part is mounted with front and rear driven wheels at the front end and the rear end of the running frame extending in the front-rear direction, respectively, and the drive wheels are arranged between the front and rear driven wheels and at positions above these. Wrapping a crawler belt between these driving wheels, and, in side view, disposing a rotation fulcrum of the lift link at a position immediately above the drive wheel, and disposing a rotation fulcrum of the lower link at a position directly below the drive wheel, Another object of the present invention is to provide a small-sized work vehicle wherein various work devices connected to a rear end of the lower link can be moved up and down by the lift arm.

Further, the present invention is characterized in that the drive wheels are interlocked with the prime mover through the transmission, and the transmission is disposed inside a triangular crawler belt in a side view. Having.

[0008]

Embodiments of the present invention will be described below.

That is, the small work vehicle according to the present invention has a basic structure in which a body frame is erected between a pair of left and right crawler traveling parts, and a prime mover unit and an operation unit are disposed on the body frame. ing.

As a characteristic structure, the running portion has front and rear driven wheels attached to a front end and a rear end of a running frame extending in the front-rear direction, respectively, between the front and rear driven wheels and between these front and rear driven wheels. A drive wheel is arranged at an upper position, a crawler belt is wound between these driving wheels, and a rotation fulcrum of a lift arm is arranged at a position directly above the drive wheel in a side view, while a lower link is arranged at a position directly below the drive wheel. Are arranged so that the various working devices connected to the rear end of the lower link can be moved up and down by the lift arm.

In addition, the drive wheels are connected to the prime mover unit via the transmission unit, and the transmission unit is disposed inside a triangular crawler belt in a side view.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

A shown in FIGS. 1 to 3 is a small work vehicle according to the present invention. The small work vehicle A has a body frame 2 erected between a pair of left and right crawler traveling parts 1, 1. A motor unit 3 and an operating unit 4 are arranged on the vehicle body frame 2, and a tilling device B as various working devices is connected to the rear of the vehicle body frame 2 via a lifting / lowering connection mechanism 5.

The traveling section 1 has front and rear driven wheels 11, 12 attached to a front end and a rear end of a traveling frame 10 extending in the front-rear direction, respectively. And a drive wheel 13 is disposed at an upper position of these, and a crawler belt 14 is wound between these driving wheels 11, 12, and 13, and four rolling wheels 15, 15, 15, 15 And the lower turning side portion 14a of the crawler belt 14 can be guided by these rolling wheels 15, 15, 15, 15. 16 is a front driven wheel support shaft, 17 is a rear driven wheel support shaft, and 18 is a drive wheel support shaft.

The front driven wheel 11 has a front driven wheel support shaft 16 disposed at substantially the same ground level as the lower surface 10b of the traveling frame 10, and is disposed above the foremost rolling wheel 15 disposed at the forefront. In addition, a floor exit angle θ is provided in a portion of the crawler belt 14 located between the ground contact point of the crawler belt 14 located immediately below the frontmost rolling wheel 15 and the lower end of the front driven wheel 11.

[0016] In this way, even on a bumpy road surface having a large step, it is easy to get over the convex portion, and the running performance can be improved.

The rear driven wheel 12 has a rear end portion at the body frame 2.
The rear driven wheel 12 is disposed so as to protrude rearward from the rear end, and the upper end of the rear driven wheel 12 is disposed equivalent to the upper surface 10a of the traveling frame 10. The upper end of the rear driven wheel 12 is a running frame
It may be arranged below the upper surface 10a of the 10.

By arranging the rear driven wheel 12 so as to protrude rearward in this way, the contact length L of the crawler belt 14 of the traveling section 1 can be formed to extend rearward, and the rear driven wheel 12 can be formed. By arranging the upper end to be equal to or lower than the upper surface 10a of the traveling frame 10 and forming the diameter as small as possible, the upper end can be arranged close to the tillage device B connected rearward, From this point as well, the contact length L of the crawler belt 14 can be extended rearward to be formed as long as possible.

Therefore, a good front-to-back weight balance can be ensured, and work efficiency and safety can be improved.

Here, the front driven wheel 11 is formed as large as possible, while the rear driven wheel 12 is formed as small as possible.
The diameter D1 of the front driven wheel 11 is formed larger than the diameter D2 of the rear driven wheel 12.

The vehicle body frame 2 includes a pair of left and right front and rear extension frame forming pieces 20 and 20 extending in the front and rear direction, and a left and right extension frame forming piece 21 traversed between the front ends of the front and rear extension frame forming pieces 20 and 20. , And a transmission portion 22 provided between the rear ends of the front and rear extension frame forming pieces 20 and 20. 23 is a front weight.

Here, the mission section 22 is, as viewed from the side,
It is arranged inside the triangular crawler belt 14.

In this way, the ground height of the mission section 22 is made as low as possible, and the vehicle center of gravity is lowered,
Good stability of the vehicle body can be ensured.

The motor unit 3 mainly includes an engine 24 and a radiator 25. The transmission unit 22 is operatively connected to the engine 24 via a transmission shaft 26. Drive wheels 13, 13 are interlockingly connected to each other via drive shaft cases 27, 27. 28 is a hood.

The operating section 4 has a handle column 30 disposed immediately behind the engine 24, and the handle column 30
A handle 31 is attached to the upper end of the vehicle, and a seat 32 is arranged at a position behind the handle 31. 33 is a fuel tank, 34 is a hydraulic oil tank, and 44 is a cabin.

The elevating mechanism 5 pivotally connects and connects the front end of the top link 37 to a top link stay 35 projecting rearward from the rear wall of the transmission section 22 via a pivot and connecting pin 36. The front ends of a pair of left and right lower links 39, 39 are pivoted and connected via pivoting and connecting pins 38, 38 serving as pivot points at the lower left and right sides of the rear of the transmission 22. The front ends of a pair of left and right lift arms 42, 42 are pivotally supported on a hydraulic case 40 provided on the upper side via a pivot 41 serving as a rotation fulcrum, and both lift arms 42, 42 are vertically rotatable. Lift links 43, 43 are provided between the rear ends of the lift arms 42, 42 and the intermediate portions of the lower links 39, 39 described above.

As described above, the tilling device B is connected to the rear end of the top link 37 and the rear ends of the pair of left and right lower links 39, 39, and the lift arms 42, 42 are vertically rotated. The tillage device B can be moved up and down through these links 37, 42, 42.

Here, the pivot 41, which is the pivot of the lift arms 42, 42, is disposed at a position directly above the drive wheel 13 in a side view, while a lower link 39, 39 is disposed at a position directly below the drive wheel 13 in a side view.
The pivoting / connecting pins 38, 38, which are the pivot points of the rotation, are arranged.

In this manner, the tilling device B can be arranged as close as possible to the vehicle body side, and the overall length from the front end of the vehicle body to the rear end of the tilling device B is shortened to achieve compactness. And the vertical movement of the center of gravity of the tillage device B when ascending and descending can be reduced, so that the vertical fluctuation of the front part of the vehicle body can be reduced by the influence, and many front weights can be provided at the front end of the vehicle body. There is no need to attach 23 mag.

In the tilling device B, a tilling claw (not shown) is attached to a lower portion of a tilling transmission case 45, a rotary cover 46 is disposed above the tilling claw, and a rear cover 47 is provided at a rear end of the rotary cover 46. Is hanging. Reference numeral 48 denotes a depth adjust frame, 49 denotes a tillage depth adjusting body, 50 denotes a top link connecting pin, 51 denotes a lower link connecting pin, and 52 denotes a drive shaft.

[0031]

According to the present invention, the following effects can be obtained.

According to the first aspect of the present invention, the traveling section includes:
Front and rear driven wheels are attached to the front end and the rear end of the traveling frame extending in the front-rear direction, respectively, and drive wheels are arranged between the front and rear driven wheels and at positions above them, and between these driving wheels. The crawler belt is wound, and, when viewed from the side, the rotation fulcrum of the lift arm is arranged just above the driving wheel, while the rotation fulcrum of the lower link is arranged just below the driving wheel, and the rear end of the lower link is arranged. Various working devices connected to the section can be moved up and down by the lift arm.

In this way, the rotation fulcrum of the lift arm is arranged just above the drive wheel in a side view, while the rotation fulcrum of the lower link is arranged just below the drive wheel.
Since various working devices connected to the rear end of the lower link can be moved up and down by the lift arm, various working devices can be arranged as close as possible to the vehicle body side. The overall length up to the rear end of the work equipment can be shortened to make it more compact, and the vertical movement of the center of gravity of the various work equipment when ascending and descending can be reduced. The size can be reduced, so that it is not necessary to attach many front weights to the front end of the vehicle body.

According to the second aspect of the present invention, the drive wheels are connected to the motor unit via the transmission unit, and the transmission unit is disposed inside a crawler belt having a triangular shape in a side view. I have.

In this manner, the stability of the vehicle body can be ensured well by lowering the height of the mission section as much as possible and lowering the center of gravity of the vehicle.

[Brief description of the drawings]

FIG. 1 is a side view of a small work vehicle according to the present invention.

FIG. 2 is a plan view of the small work vehicle.

FIG. 3 is a front view of the small work vehicle.

[Explanation of symbols]

 A Small work vehicle 1 Running unit 2 Body frame 3 Engine unit 4 Operating unit 5 Elevating mechanism

Claims (2)

[Claims] A body frame (2) is provided between a pair of left and right crawler-type traveling parts (1, 1), and a motor unit (3) and an operating part (4) are mounted on the body frame (2). In the small work vehicle arranged, the traveling section (1) has front and rear driven wheels (11, 12) attached to the front end and rear end of the traveling frame (10) extending in the front-rear direction, respectively. A drive wheel (13) is arranged between the rear driven wheels (11, 12) and above the rear driven wheels (11, 12),
Crawler (14) is wound between 3), and lift arm (4) is positioned just above drive wheel (13) in side view.
While the rotation fulcrum (2) is disposed, the rotation fulcrum (38) of the lower link (39) is disposed immediately below the drive wheel (13), and the rotation fulcrum (38) is provided at the rear end of the lower link (39). A small work vehicle characterized in that various connected work devices (B) can be moved up and down by the lift arm (42). The drive wheel (13) is interlockingly connected to a motor unit (3) via a transmission unit (22), and is connected to the transmission unit (2).
2. The small work vehicle according to claim 1, wherein the side work is arranged inside a crawler belt having a triangular shape in a side view. 3.