JP2001063306A - Tread changing device of work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance parts commonization between an axle housing of tread change type and an axle housing of a tread fixing type. SOLUTION: A front axle housing 20 is formed such that inner axles 20b, 20b are inserted slidably in right and left ends of an outer axle 20a and horizontal length can be extendable. Tread positioning devices 50, 50 are detachably mounted to both ends of the front axle housing 20 and tread fixing devices 60, 60 are detachably mounted to both ends of the front axle housing 20. In a work vehicle of tread fixing type, by removing the tread positioning devices 50, 50 and the tread fixing devices 60, 60, the outer axle 20a of tread changing type can be used in common.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tread changing device for a working vehicle, and more particularly to a tread changing device for a working vehicle having an axle housing formed to be extendable and retractable.

[0002]

2. Description of the Related Art Outer axles (center cases) are used in work vehicles used for construction work and agricultural work.
An axle housing is formed so as to be extendable by slidably inserting an inner axle into the inner axle, and the tread can be changed by sliding the inner axle according to the work content. And
A tread positioning device for determining the sliding position of the inner axle and a tread fixing device for fixing the inner axle and stopping it from rotating are provided integrally with the outer axle.

[0003]

The tread changing device of this type of work vehicle has a tread positioning device and a tread fixing device integrally provided on an outer axle, so that a normal tread fixing type axle housing and a tread changing type are used. It is difficult to share the outer axle with the axle housings of the above, and the axle housings have to be formed separately for each.

[0004] Therefore, there arises a technical problem to be solved in order to share parts between the axle housing of the tread changing type and the axle housing of the fixed tread type, and the present invention solves this problem. With the goal.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been proposed to achieve the above object, and a tread positioning device and a tread fixing device are opposed to each other before and after an axle housing formed to be extendable. A cylinder having an elongated hole along the axle housing, a shaft having a plurality of positioning holes that slide through the cylinder and insert a pin together with the elongated hole. On the other hand, the tread fixing device includes a cylindrical body having an opening for inserting a fixing bolt, and a shaft that slides in the cylindrical body and has a plurality of fixing holes through which the fixing bolt is inserted together with the opening. The tread changing device of the work vehicle, and the tread positioning device and the tread fixing device are inclined with respect to the horizontal plane of the axle housing. Disposed, there is provided a tread change device for a working vehicle arranged to be visible from the driver's seat at least tread positioning device.

[0006]

An embodiment of the present invention will be described below in detail with reference to the drawings. FIGS. 1 to 3 show a tractor 10 as an example of a work vehicle, in which an engine (not shown) is mounted on a front part of the fuselage, covered with a hood cover 11, and a cabin 12 is provided from a center part to a rear part of the fuselage. The driver's seat 13 is provided inside the driver's seat 13, and a meter panel 14, a handle post 15, and the like are arranged in front of the driver's seat 13.
A transmission case 16 is fixed below the driver's seat 13. Further, a rotary working machine 18 is connected to a rear portion of the body via a link mechanism 17.

On the other hand, a stay 19 is suspended from the front lower portion of the fuselage, and a pin 21 projecting from the front of the front axle housing 20 at the center in the left-right direction is pivotally connected to the stay 19, so that the front axle housing 20 is mounted. The front axle housing 20 has front wheels 22, 22.
Attach. Further, rear axle housings 23, 23 are fixedly provided on both side surfaces of the transmission case 16, and rear wheels 24, 24 are mounted on respective outer end portions.

FIG. 4 is a plan view of the front axle housing 20. Since the front axle housing 20 is formed symmetrically, the description of the right portion is partially omitted, and the left portion will be described in detail. In the figure, the pin 21 protrudes from the front of the center of the front axle housing 20 (the upper part in the figure is the front of the body), and the drive input unit 30 is provided on the rear of the center of the front axle housing 20. ing.
The power input from the drive input unit 30 is transmitted from the front differential gear 31 to the left and right front axle shafts 32,32. Knuckle arms 33 are provided at both ends of the front axle housing 20, and each knuckle arm 33 is provided with a king pin 34.
And a wheel hub mounting bracket 3 on the outer side of the knuckle arm 33.
5 is fixedly formed so that the front wheel 22 described above can be mounted.

Above the drive input section 30, a steering cylinder 36 of the hydraulically operated steering system is provided with a bolt 3
At 7, 37, it is fixed to the rear upper portion of the front axle housing 20. The steering cylinder 36 is a double rod type hydraulic cylinder in which piston rods 39, 39 project from both sides of a case 38. Both ends 40a, 40a of a bracket 40 having a U-shape in plan view are provided at the distal ends of both piston rods 39, 39. When the steering cylinder 36 is driven, the piston rods 39, 3 are fixed.
The bracket 40 is formed integrally with the bracket 9 so as to move in the left-right direction.

Reference numeral 41 denotes a locking member fixed near both ends of the rear surface of the bracket 40. As shown in FIG.
A slide hole 42 is formed in the locking tool 41 in the left-right direction, and a slit 43 is provided in a lateral direction of a rear surface of the locking tool 41 so that a part of the slide hole 42 is cut out.
Is formed in a substantially C-shape when viewed from the side. Further, in order to insert a stopper bolt 48 described later, an insertion hole (a fool hole) is provided from the rear end of the upper surface of the locking tool 41 to the slit 43.
A hole 44b is formed in the same axis as the insertion hole 44a from the slit 43 toward the lower surface of the locking tool 41.
Is provided.

Then, the slide holes 4 of the respective locking members 41 are formed.
2, the slide rod 46 of the tie rod end 45 is inserted from the left and right outer directions. A plurality of semicircular grooves 47, 47,... Are previously formed in the rear surface of the slide rod 46 in the longitudinal direction. By inserting the stopper bolt 48 from above the insertion hole 44a in a state where the one groove 47 coincides with the insertion hole 44a, a part of the stopper bolt 48 is engaged with the groove 47,
When the stopper bolt 48 is rotated and screwed into the opening hole 44b, the slit 43 becomes narrower, the inner diameter of the slide hole 42 is reduced, and the slide rod 46 is tightened and locked by the locking member 41. Is done. A tie rod 49 is formed by the bracket 40 and the tie rod ends 45, 45, and the left and right knuckle arms 33,
33 are connected.

As shown in FIG. 4, the tip portions 45a, 45a of the left and right tie rod ends 45, 45 are pivotally attached to the knuckle arms 33, 33, and the steering cylinder 36 is driven to drive the piston rods 39, 39. Moves to the right, the bracket 40 also moves in the same direction,
Tie rod end 4 locked to left and right locking tools 41, 41
5, 45 is drawn to the right. Accordingly, the left and right knuckle arms 33, 33 rotate counterclockwise in the drawing around the respective king pins 34, 34, and the front wheels 22, 22 turn to the left, so that the aircraft can turn left. On the other hand, when the piston rods 39, 39 move to the left, the left and right knuckle arms 33, 33 rotate clockwise in the figure by an operation symmetrical to the above, and the body can turn right. Become.

The front axle housing 20 is formed such that inner axles 20b, 20b are slidably inserted into left and right ends of an outer axle (center case) 20a so that the left and right widths of the axle housing can be expanded and contracted. Inner axle 2 depending on the content
The tread can be changed by sliding 0b and 20b. In the present embodiment, the inner axle 20a is provided at both left and right ends of the outer axle 20a.
Although b and 20b are mounted, the inner axle 20b may be provided on only one of them, and the tread may be formed so that only one side can expand and contract.

Further, the left and right ends of the front axle housing 20 have inner axles 20b at the front and rear, respectively.
Tread positioning device 5 for determining slide position
0 and a tread fixing device 60 for fixing and stopping the inner axle 20b from rotating.

As shown in FIGS. 6 to 8, the tread positioning device 50 comprises a cylindrical tube 51 and a shaft 52 slidably fitted in the tube 51. While drilling a long hole 53 in the longitudinal direction,
A plurality of positioning holes 5 are formed on the upper surface of the shaft 52 in the longitudinal direction.
4, 54... Are provided so as to face from the long holes 53. By inserting the pin 55 from above the long hole 53 and inserting the pin 55 into an arbitrary positioning hole 54, the slide end position of the shaft 52 with respect to the cylindrical body 51 can be determined. The tread positioning device 50 is detachably attached to the outer axle 20a of the front axle housing 20 by bolting.

On the other hand, the tread fixing device 60 comprises a cylindrical tube 61, a shaft 62 slidably fitted in the tube 61, an inverted L-shaped plate 63 provided on the upper portion of the shaft 62, and the like. The long side 63a of the plate 63
Is disposed in parallel with the shaft 62 and slidably contacts a guide portion 64 integrally provided on the upper portion of the cylindrical body 61. The short side 63b perpendicular to the long side 63a is Is bolted to one end face.

An opening hole 65 having a screw portion is provided in the guide portion 64 and the long side 6 of the plate 63 is provided.
3a, a plurality of fixing holes (idiot holes) 66, 66.
And the plate 63 slides to open the opening hole 6.
When any one of the fixing holes 66 is moved to the upper part of 5, the fixing bolt 67 is inserted from above the fixing hole 66 so that the fixing bolt 67 can be screwed into the opening hole 65. In particular, the guide portion 64 is not provided on the upper part of the cylindrical body 61, and the opening hole 65 having the screw portion is provided directly on the cylindrical body 61, and the long side 63a of the plate 63 can be slid on the upper surface of the cylindrical body 61. You may form so that it may contact. Further, the tread fixing device 60 is also provided in the front axle housing 20.
Is detachably attached to the outer axle 20a by bolts.

Further, a flange-shaped plate 25 is fixed to the inner axle 20b, one end of the plate 25 is fixed to the end surface of the shaft 52 of the tread positioning device 50, and the other end of the plate 25 is connected to the tread. It is fixed to the end face of the shaft 62 of the fixing device 60. Therefore,
The shaft 52 and the shaft 62 slide together as the inner plate 20b moves in the left-right direction.

Next, the tread changing procedure will be described in further detail with reference to FIGS. When changing the tread, first, a pin or the like is inserted into the locking holes 33a, 33a provided in the left and right knuckle arms 33, 33, and the rotation of the knuckle arms 33, 33 is fixed. The tie rod end 45 is relaxed or detached from the locking tool 41. For example, the left inner axle 20
To move b, the stopper bolt 48 of the right locking tool 41 is removed, and the locking tool 41 is loosened to make the slide rod 46 of the right tie rod end 45 free.

In this state, the steering cylinder 3
6 to drive the piston rods 39, 39 to the left, the left tie rod end 45 locked by the left locking tool 41 is pushed to the left, and the left knuckle arm 33 is moved.
The inner axle 20b on the left side is integrally pulled out. Thus, the front axle housing 2
The width of the left portion of the 0 is extended, and the tread is enlarged. Conversely, if the piston rod 39 is moved to the right,
The left inner axle 20b is drawn inward, and the width of the left portion of the front axle housing 20 is reduced, and the tread is reduced.

Subsequently, the right inner axle 20b is moved. In this case, contrary to the above, the stopper bolt 48 of the left locking tool 41 is removed, and the locking tool 41 is loosened to make the slide rod 46 of the left tie rod end 45 free. In this state, if the steering cylinder 36 is driven to move the piston rods 39, 39 left or right, the right tie rod end 45 locked by the right locking tool 41 is pushed left or right, The right inner axle 20b is pushed and pulled integrally with the right knuckle arm 33. Thus, the width of the right side portion of the front axle housing 20 expands and contracts, and the tread expands or contracts.

As shown in FIG.
Even when the distance between the end face of the knuckle arm 33 and the knuckle arm 33 is short and it is difficult to attach a member that expands and contracts the tie rod 49, the axis of the piston rod 39 and the axis of the slide rod 46 of the tie rod end 45. And the piston rod 39 and the tie rod end are wrapped in parallel with each other, and a telescopic member (the locking tool 41 and the slide rod 46 in the present embodiment) is interposed in the wrapped portion, so that the length of the tie rod 49 is reduced. It is possible to expand and contract the length.

When expanding the left tread, as shown in FIG. 7 (a), for example, a pin 5 is inserted into the first positioning hole 54 from the left of the left tread positioning device 50.
5 and the left tread fixing device 60
Loosen the fixing bolt 67 and remove it. In such a state,
As described above, the rotation of the left and right knuckle arms 33, 33 is fixed, and the right tie rod end 45 is fixed to the locking tool 41.
If the left inner axle 20b is pulled out to the left by driving the steering cylinder 36,
The shaft 52 of the tread positioning device 50 is
1 and moves to the left while the shaft 62 of the tread fixing device 60 slides inside the cylinder 61 and moves to the left.

When the pin 55 inserted into the shaft 52 comes into contact with the left end of the elongated hole 53, the shaft 52 cannot slide further leftward as shown in FIG. The movement of the left inner axle 20b stops. After that, the tread fixing device 60
When the fixing bolt 67 is inserted into the fixing hole 66 and screwed into the opening hole 65, the slide of the shaft 62 is restrained and the tread is fixed.

On the other hand, when the tread is narrowed by pulling the left inner axle 20b rightward, when the pin 55 inserted into the shaft 52 comes into contact with the right end of the long hole 53, the shaft 52 moves to the right. Sliding becomes impossible, and the movement of the inner axle 20b stops. still,
When the right tread is changed, the right tread positioning device 50 and the right tread fixing device 60 are operated symmetrically to the above, so that the tread positioning and tread fixing of the right portion can be easily performed. .

Regardless of whether the tread is expanded or contracted, by changing the insertion position of the pin 55, the slide end position of the shaft 52 is changed, and tread positioning in several steps can be performed very easily. . Although not shown, the pins 55 are inserted into any two positioning holes 54 provided in the shaft 52 of the tread positioning device 50, so that the tread in two stages can be connected to the pins 55. Can be changed alternately without replacement.

As shown in FIGS. 1 and 6, the tread positioning device 50 and the tread fixing device 60 are disposed opposite to each other in front of and behind the front axle housing 20.
Since the front axle housing 20 is inclined with respect to the horizontal plane, it can be viewed from the driver's seat 13 installed above and behind the front axle housing 20. It is easy to visually recognize in which position is changed.
In addition, when the tread is changed, when the pin 55 is inserted and removed and when the fixing bolt 67 is attached and detached, it is possible to perform the operation while observing the tire obliquely from behind rather than through the tire, thereby improving workability.

The tread positioning device 50 and the tread fixing device 60 are connected to the front axle housing 2.
The outer axle 20a can be shared between the fixed tread-type work vehicle and the tread-changeable work vehicle because the outer axle 20a can be attached to and detached from the outer axle 20a.

The present invention can be variously modified without departing from the spirit of the present invention, and it goes without saying that the present invention extends to the modified ones.

[0030]

As described in detail in the above embodiment, the invention according to the first aspect of the present invention has a tread positioning device and a tread fixing device opposed to each other before and after an axle housing formed to be extendable. Since the axle housing is detachably mounted, the shape of the axle housing is not biased toward one side, and the strength can be made uniform. Further, by removing the tread positioning device and the tread fixing device, it is possible to easily provide a tread fixed type working vehicle.
Therefore, the axle housing can be shared between the tread fixed type and the tread changing type, and the cost can be reduced by sharing parts.

According to the second aspect of the present invention, the tread changing portion of the axle housing formed so as to be extendable and contracted is inclined with respect to a horizontal plane, and the tread changing portion is disposed so as to be visible from the driver's seat. The tread change position can be easily visually recognized while sitting in the driver's seat. In addition, the present invention has various effects, such as improved workability when changing the tread.

[Brief description of the drawings]

 The figure shows an embodiment of the present invention.

FIG. 1 is a side view of a tractor as an example of a work vehicle.

FIG. 2 is a front view of the tractor.

FIG. 3 is a rear view of the tractor.

FIG. 4 is a plan view of a front axle housing.

FIG. 5 is a perspective view of a main part of a bracket and a tie rod end.

FIG. 6 is a side view of the front axle housing.

FIGS. 7A and 7B show essential parts of a tread positioning device and a tread fixing device, wherein FIG. 7A is a plan view when the tread is contracted, and FIG. 7B is a plan view when the tread is enlarged.

8A and 8B show a main part of the tread fixing device, wherein FIG. 8A is a rear view when the tread is contracted, and FIG. 8B is a rear view when the tread is enlarged.

[Explanation of symbols]

 13 Driver's seat 20 Front axle housing 50 Tread positioning device 60 Tread fixing device

Claims (2)

[Claims] 1. A tread positioning device and a tread fixing device are detachably disposed opposite to each other in front of and behind an extendable axle housing, and the tread positioning device has a long hole along the axle housing. A cylinder having a plurality of positioning holes that slide in the cylinder and insert the pins together with the elongated holes, while the tread fixing device has an opening for fixing bolt insertion. A tread changing device for a working vehicle, comprising: a body; and a shaft having a plurality of fixing holes that slide in the cylindrical body and through which fixing bolts are inserted together with the opening holes. 2. The tread of a work vehicle according to claim 1, wherein the tread positioning device and the tread fixing device are disposed so as to be inclined with respect to a horizontal plane of the axle housing, and at least the tread positioning device is disposed so as to be visible from a driver's seat. Change device.