JPH1142948A - Traveling drive device of working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the whole machine body by arranging reduction gear cases on both sides of a front accelerator case so as to be protruded substantially horizontally forward, fixing drive wheels to the front parts of the reduction gear cases, and arranging a working machine between the lateral-reduction gear cases. SOLUTION: Reduction gear cases 29 are protruded substantially horizontally forward, and base parts of the rising and falling links 50L, 50R of front side reel mores 8FL, 8FR are rotatably supported on the inside surfaces of the reduction gear cases 29. The front center reel more 8FM is suspended from the top end of the rising and falling link 51, and the base part of the rising and falling link 51 is pivotally supported by a mission case 1 so as to be capable of being raised/lowered and rotated by a hydraulic cylinder. A space P is formed in the front lower part of a machine body frame between the lateral reduction gear cases 29, and the front center reel more 8FM is arranged therein. When three reel mores 8FL, 8FM, 8FR are provided in the front of the machine body, the central front center reel more 8FM can be arranged between the lateral front wheels and satisfactorily settled, the whole equipment body length can be shortened, and the weight balance is also improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for reducing the power output from a transmission case to two front wheels of a working vehicle and transmitting the output to drive wheels.

[0002]

2. Description of the Related Art Conventionally, a hydraulic pump is driven by power from an engine, and the hydraulic pump is fluidly connected to a hydraulic motor through a closed circuit.
One transmits power to the differential device via the auxiliary transmission to drive the main drive wheels (rear wheels or front wheels), and the other transmits power from the output shaft of the hydraulic motor to the differential device via the transmission shaft to perform auxiliary driving. A technique for driving a wheel (a front wheel or a rear wheel) is known. For example, Japanese Utility Model Publication No. 60-321
This is like the technique described in Japanese Patent Publication No. 27-27. In addition, a technique in which a mower (working machine) is arranged in front of a traveling machine body is also known. For example, this is a technique disclosed in Japanese Patent Application Laid-Open No. 9-121645.

[0003]

However, in the prior art, the mowers are arranged in front of the traveling body or in the abdomen between the front and rear wheels, and when a plurality of mowers are arranged in front of the body. , Are arranged so as to overlap each other when viewed from the front so as not to cause uncut leaves. Therefore, in side view, the work equipment must be displaced back and forth, so the overall length is long, and the mower at the front center needs to be supported by a long arm so that it can be raised and lowered. The driving force also had to be increased. In addition, when the mower at the front center is disposed at the front end, the turning radius increases, the turning radius of the mowing portion also increases, and the overlap length with the mowers on both sides of the mowing portion also needs to be increased.

[0004]

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described. In the configuration in which the working machine is disposed in front of the front two-wheel traveling body, a reduction case is disposed on both sides of the front axle case, the reduction case projects substantially horizontally forward, and a wheel shaft is provided in front of the reduction case. Support,
A drive wheel is fixed to the wheel shaft, and a working machine is arranged between the left and right deceleration cases.

[0005]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an overall side view of a work vehicle in which a traveling drive device of the present invention is applied to a mower, FIG. 2 is a schematic diagram of the travel drive device of the present invention, and FIG.
FIG. 4 is a plan sectional view of the speed reduction case.

An embodiment in which a mower is mounted using the traveling drive device of the present invention as a working machine will be described. The front wheel is the main drive wheel 5,
The rear wheel is a sub-drive wheel 6, and the sub-drive wheel 6 is also a steering wheel. The main drive wheels 5 are supported at the front of the body frame 19, and the sub drive wheels 6 are supported at the rear. Front reel mowers 8FL, 8FM, and 8FR are arranged in front of the main drive wheels 5 so as to be able to move up and down. Side reel mowers 8S and 8S are arranged on the abdomen of the machine between the wheels 5 and the auxiliary drive wheels 6 so as to be able to move up and down. However, the work machine (front reel mower 8
FM). An operating unit A is arranged on the front of the body frame 19, and the engine E is mounted on the rear of the body frame 19 and covered with a hood.

Next, the drive configuration of the main drive wheels 5 and the sub drive wheels 6 will be described. 2 and 3, a variable displacement first hydraulic pump P1 is provided on the output shaft of the engine E, and a constant displacement first hydraulic motor M1 is attached to the transmission case 1 so that the first Hydraulic pump P1 and the first hydraulic motor M1 are fluidly connected by piping or an oil passage, and the first HS
The output shaft of the first hydraulic motor M <b> 1 is connected to the input shaft 2 of the transmission case 1.
An auxiliary transmission 3 is accommodated in the transmission case 1,
One of the output shafts 4 of the auxiliary transmission 3 is transmitted to the first differential device D1 via gears to drive the main drive wheels 5.5, and the other of the output shaft 4 is connected to the other via the clutch 7. To the input shaft 9 of the second hydraulic pump P2. The clutch 7 is an overrunning clutch or ON / OF
It is composed of an F clutch.

As shown in FIG. 2, for example, the auxiliary transmission 3 has a large-diameter gear 10 and a small-diameter gear 11 fixed on an input shaft 2, and a double sliding gear 12 on an output shaft 4. The splines are slidably fitted to each other, and are fitted to each other so that they cannot rotate with each other. A high-speed rotation is obtained by meshing one gear 12a of the double sliding gear 12 with the large-diameter gear 10, and a low-speed rotation is obtained by meshing the other gear 12b with the small-diameter gear 11. Is possible. However, the number of shift steps is not limited, and may be one step or two or more steps.

A gear 13 is fixed to one end of the output shaft 4, the gear 13 is meshed with a gear 15 on a reduction shaft 14, and a bevel gear 16 is fixed to the reduction shaft 14,
The bevel gear 16 is engaged with the ring gear 17 of the first differential device D1. The axles 18L and 18R protrude from the first differential device D1, and the axles 18L and 18R
Is the axle case 5 protruding on both sides of the transmission case 1
Axle case 52
A reduction case 29 accommodating the reduction gear (bull gear) of the present invention is fixed to the end of 52 so that the main drive wheels 5.5 can be driven by reducing the speed with the reduction gear. In this way, the first hydraulic motor M1 is driven, and the auxiliary transmission 3
After the power is shifted by the output shaft 4, the power is
15, transmitted to the first differential device D1 via the bevel gear 16, and drives the main drive wheels 5.5.

[0010] The second hydraulic pump P2 is fluidly connected to the second hydraulic motor M2 via the pipings 20 and 20 to form a closed circuit, thereby forming a second HST type transmission. The second hydraulic pump P2 and the second hydraulic motor M2 can both be of a constant displacement type or a variable displacement type, and one is a variable displacement type and the other is a constant displacement type. You can also. The second hydraulic motor M
The second output shaft 21 is fixedly provided with a bevel gear 22. The bevel gear 22 meshes with a ring gear 24 of a second differential device D2 in a rear axle housing 23, and an axle protruding left and right from the second differential device D2. Sub-drive wheels 6.6 are fixedly provided at both ends of 25L and 25R.

In such a configuration, by changing the angle of the movable swash plate of the first hydraulic pump P1, the rotation of the output shaft of the first hydraulic motor M1 is changed steplessly.
The rotation proportional to the rotation is transmitted to the main drive wheels 5 to drive the work vehicle to travel. When the clutch 7 is an overrunning clutch, the output shaft 4
When the rotation speed of the output shaft 4 changes, the clutch is brought into “contact” to transmit power to the input shaft 9. Regardless of the rotation direction, the rotation of the output shaft 4 can be performed in either forward rotation or reverse rotation. When the number changes, it becomes "contact", and when it becomes steady rotation, it becomes "disconnection". Therefore, when this work vehicle is traveling straight, the second hydraulic pump P2 is not driven, and
No. 6 is in an idling state, no drag occurs, and the field scene (turf surface) is not damaged.

When one side of the main drive wheels 5, 5 falls into a mud or a depression during running and slips, the axle 1
The load driving the 8L and 18R changes, and the rotation speed of the output shaft 4 changes. Then, the overrunning clutch 7 automatically comes into "contact", drives the second hydraulic pump P2, and operates the second hydraulic motor M2 to drive the sub-drive wheels 6, 6, so that the muddy Etc. can escape. However, when the clutch 7 is an ON / OFF clutch, the clutch is “disengaged” during normal running,
Prevents dragging of the auxiliary drive wheels 6 and 6, when escaping from mud, etc., sets the clutch to "closed" and can escape as a four-wheel drive. When using an ON / OFF clutch, 2WD and 4WD can be arbitrarily set. Can be switched.

As shown in FIGS. 1, 2 and 3, the deceleration case 29, which is an essential part of the present invention, projects substantially forward in the horizontal direction. Elevating link 50 of reelmore 8FL / 8FR
The base of L.50R is rotatably pivoted, and is vertically moved by a hydraulic cylinder (not shown), so that the deceleration case 29 is protruded forward by the length of the lifting link 50L.50.
R can be configured to be short, and a support bracket for the lifting links 50L and 50R is not required. Further, the front center reel mower 8FM is hung at the tip of the lifting link 51, and the base of the lifting link 51 is pivotally supported by the transmission case 1 so that it can be raised and lowered by a hydraulic cylinder.

A space P is formed in front of and below the body frame 19 between the left and right deceleration cases 29, 29, and a front center reel mower 8FM is arranged in the space P between the deceleration cases 29, 29. Therefore, when three reel mowers 8FL, 8FM, and 8FR are provided in front of the fuselage, the center front center reel mower 8FM is disposed between the left and right front wheels, so that the fit is well protected, the overall length can be shortened, and Can be shortened, and the elevating mechanism can be arranged in the space, so that the space can be used effectively. In addition, since it is arranged at the center of the fuselage, the weight balance can be improved. The deceleration case 29 can be arranged vertically to increase the vehicle height. However, since the work vehicle mainly performs lawn mowing, the vehicle height should be rather low and the center of gravity should be low. They can run stably and work.

The structure inside the deceleration case 29 is shown in FIG.
As shown in the figure, the speed reduction case 29 is fixed to the end of the axle case 52. The speed reduction case 29 is configured to be divided into right and left, and the axle 18 is inserted into the rear portion of the speed reduction case 29 and is rotatable via bearings. It is supported by. The axle 18
A small reduction gear 53 is fixed on the end of the gear. Also,
A wheel shaft 5 is provided at the front between the left and right cases 29a and 29b.
5 is rotatably supported via a bearing, and the wheel shaft 5
A reduction large-diameter gear 54 is fixed on one end of the gear 5 and constantly meshes with the reduction small-diameter gear 53, and the other end of the wheel shaft 55 projects sideward from the reduction case 29, and is mounted on an external wheel shaft 55. The main drive wheels 5 are fixedly mounted.

As described above, by housing the reduction gear in the reduction case 29, the transmission torque can be reduced by reducing the reduction ratio of the first differential device D1, and the first differential device D1 itself can be reduced in size. To increase the ground clearance,
The space P can also be increased. The tread can be widened by interposing the reduction case 29, and the tread can be changed by preparing several types of the reduction case 29.

[0017]

As described above, the present invention has the following advantages. That is, since the reduction case is disposed on both sides of the front axle case and the reduction case is projected forward in the horizontal direction, a space can be formed between the left and right reduction cases, and the working machine is disposed in this space. Thus, the work machine is well placed and protected by the reduction case and the drive wheels. In addition, since the working machine is arranged between the driving wheels, the forward projection of the machine is small and the overall length can be shortened, the arm for lifting and lowering can be shortened, and the overlapping length is short for working machines such as mowers it can.
In addition, the lifting mechanism can be arranged in the space, and the space can be used effectively. In addition, since it is arranged on the center side in the longitudinal and lateral directions of the body, the weight balance can be improved. Further, since the deceleration case is arranged not in the vertical direction but in the horizontal direction, the body can be set at a low center of gravity, and stable traveling can be performed.

[Brief description of the drawings]

FIG. 1 is an overall side view of a working vehicle in which a traveling drive device of the present invention is applied to a mower.

FIG. 2 is a schematic diagram of a traveling drive device of the present invention.

FIG. 3 is a diagram showing a drive configuration.

FIG. 4 is a plan sectional view of a speed reduction case.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmission case 5 Main drive wheel 8 Reel mower 18 Axle 29 Deceleration case 52 Axle case 55 Wheel axle

Claims (1)

[Claims] In a configuration in which a work machine is disposed in front of a front two-wheel traveling body, a reduction case is disposed on both sides of a front axle case, and the reduction case protrudes substantially horizontally forward. A traveling drive device for a working vehicle, wherein a wheel shaft is supported by a portion, a driving wheel is fixed to the wheel shaft, and a working machine is disposed between the left and right deceleration cases.