JP4013418B2 - Tread changing device for work vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tread changing device for a work vehicle, and more particularly to a tread changing device for a work vehicle having an axle housing formed to be extendable and contractible.
[0002]
[Prior art]
In work vehicles used for construction work, agricultural work, etc., the inner axle is slidably inserted into the outer axle (center case) to make the axle housing extendable, and the inner axle is slid according to the work contents. The thing which made it possible to change a tread by doing is known. A tread positioning device for determining the sliding position of the inner axle and a tread fixing device for fixing the inner axle to stop the rotation are integrated with the outer axle.
[0003]
[Problems to be solved by the invention]
In this type of work vehicle tread changing device, since the tread positioning device and the tread fixing device are integrally provided on the outer axle, the outer axle is shared by the normal tread fixing type axle housing and the tread changing type axle housing. However, it was difficult to manufacture the axle housings, and the axle housings had to be formed separately.
[0004]
Therefore, there is a technical problem to be solved in order to share parts between the tread change type axle housing and the tread fixed type axle housing, and the present invention aims to solve this problem. To do.
[0005]
[Means for Solving the Problems]
The present invention has been proposed in order to achieve the above object, and the invention according to claim 1 is capable of extending and contracting by inserting the inner axles (20b, 20b) slidably into the left and right ends of the center case (20a). left and right front and rear of the formed axle housing (20), the tread positioning device (50, 50) and the tread fixing device (60, 60) and against each other removably arranged, the tread positioning device (50, 50 ) Includes a cylindrical body (51, 51) having a long hole ( 53, 53 ) along the axle housing (20) , and slides in the cylindrical body ( 51, 51 ) and the long hole (53, 53). And a shaft (52, 52) having a plurality of positioning holes (54, 54...) Through which the pins (55, 55) are inserted, and the tread fixing device (60, 60) . Is a cylindrical body (61, 61) having an opening hole (65, 65) for inserting the fixing bolt (67, 67) , and slides in the cylindrical body (61, 61) and the opening hole ( 65, 65 ). with inverted L-shaped plates (63, 63) Tsukino a shaft (62, 62) having a plurality of fixing holes for inserting the fixing bolts (67) (66, 66 ...), and, the inner axle (20b , 20b) and a bowl-shaped plate (25, 25) are fixed to each other, and one end of the plate (25, 25) is fixed to the end surface of the shaft (52, 52) of the tread positioning device (50, 50). And a tread changing device for a work vehicle in which the other end of the plate (25, 25) is fixed to the end surface of the shaft (62, 62) of the tread fixing device (60, 60) .
In the invention according to claim 2 , the tread positioning device ( 50, 50 ) and the tread fixing device ( 60, 60) are arranged to be inclined with respect to the horizontal plane of the axle housing (20) , and at least the tread positioning device. The tread changing device for a work vehicle according to claim 1, wherein ( 50, 50) is disposed so as to be visible from the driver's seat (13) .
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. 1 to 3 show a tractor 10 as an example of a work vehicle. An engine (not shown) is mounted on the front part of the machine body and covered with a bonnet cover 11, and a cabin 12 is installed from the center part to the rear part of the machine body. A driver's seat 13 is provided in the interior, a meter panel 14 and a handle post 15 are disposed in front of the driver's seat 13, and a transmission case 16 is fixed below the driver's seat 13. . A rotary working machine 18 is connected to the rear part of the machine body via a link mechanism 17.
[0007]
On the other hand, a stay 19 is suspended from the front lower part of the fuselage, and a pin 21 protruding from the front surface of the center portion in the left-right direction of the front axle housing 20 is pivotally attached to the stay 19, and the front axle housing 20 attaches the pin 21. The front wheels 22 and 22 are attached to the left and right ends of the front axle housing 20 while being supported so as to be swingable in the center. Further, rear axle housings 23, 23 are fixed on both side surfaces of the transmission case 16, and rear wheels 24, 24 are mounted on the respective outer ends.
[0008]
FIG. 4 is a plan view of the front axle housing 20, and is formed symmetrically. Therefore, a part of the right side part is omitted, and the left side part is described in detail. In the figure, the pin 21 projects from the front surface of the center portion of the front axle housing 20 (the upper side in the figure is the front of the fuselage), and the drive input portion 30 is provided on the rear surface of the center portion 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 and 32. Knuckle arms 33, 33 are provided at both ends of the front axle housing 20, and each knuckle arm 33 is supported so as to be pivotable left and right around a king pin 34, and further, a wheel is provided on the outer side of the knuckle arm 33. A hub mounting bracket 35 is fixed and formed so that the above-described front wheel 22 can be mounted.
[0009]
A steering cylinder 36 of an all-hydraulic steering device is fixed to the upper rear portion of the front axle housing 20 with bolts 37 and 37 above the drive input unit 30. The steering cylinder 36 is a double rod type hydraulic cylinder in which piston rods 39, 39 protrude on both sides of a case 38, and both end portions 40 a of a bracket 40 having a U-shape in plan view are formed at the tip portions of both piston rods 39, 39. 40b is fixed, and when the steering cylinder 36 is driven, the bracket 40 is formed so as to move in the left-right direction integrally with the piston rods 39, 39.
[0010]
Reference numeral 41 denotes a locking tool fixed in the vicinity of both end portions of the rear surface of the bracket 40. As shown in FIG. 5, a slide hole 42 is opened in the left-right direction in the locking tool 41, and a slit 43 is provided in the lateral direction of the rear surface of the locking tool 41 so that a part of the slide hole 42 is cut out. The side view of the locking tool 41 is formed in a substantially C shape. Further, in order to insert a stopper bolt 48 to be described later, an insertion hole (baka hole) 44a is opened from the rear end of the upper surface of the locking tool 41 to the slit 43, and the lower surface of the locking tool 41 is opened from the slit 43. The opening hole 44b is provided with the same axial center as the insertion hole 44a.
[0011]
Then, the slide rod 46 of the tie rod end 45 is inserted into the slide hole 42 of each locking tool 41 from the left and right outer sides. A plurality of semicircular grooves 47, 47... Are opened in the longitudinal direction in advance on the rear surface of the slide rod 46, and the slide rod 46 is slid in the slide hole 42 of the locking tool 41. When a stopper bolt 48 is inserted from the upper part of the insertion hole 44a in a state where the groove 47 and the insertion hole 44a coincide with each other, a part of the stopper bolt 48 is engaged with the groove 47, and further, the stopper bolt 48 is engaged. Is rotated and screwed into the opening hole 44b, the slit 43 is narrowed, the inner diameter of the slide hole 42 is reduced, and the slide rod 46 is tightened and locked to the locking tool 41. The bracket 40 and the tie rod ends 45, 45 constitute a tie rod 49, and the left and right knuckle arms 33, 33 are connected by the tie rod 49.
[0012]
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 move the piston rods 39, 39 to the right. When moved, the bracket 40 also moves in the same direction, and the tie rod ends 45, 45 locked to the left and right locking tools 41, 41 are pulled to the right. Therefore, the left and right knuckle arms 33, 33 rotate around the respective king pins 34, 34 in the counterclockwise direction in the figure, and the front wheels 22, 22 turn leftward so that the aircraft can turn left. On the other hand, when the piston rods 39 and 39 are moved to the left, the left and right knuckle arms 33 and 33 are rotated clockwise in the figure by a symmetric operation, and the aircraft can turn right. Become.
[0013]
Here, the front axle housing 20 is formed such that inner axles 20b and 20b are slidably inserted into both left and right ends of an outer axle (center case) 20a so that the right and left width of the axle housing can be expanded and contracted. The tread can be changed by sliding the inner axles 20b and 20b. In the present embodiment, the inner axles 20b and 20b are attached to the left and right ends of the outer axle 20a. However, the inner axle 20b may be provided only on one of them, and the tread may be formed to be extendable and retractable only on one side. .
[0014]
Further, at the left and right ends of the front axle housing 20, there are a tread positioning device 50 for determining the sliding position of the inner axle 20b in the front and rear, and a tread fixing device 60 for fixing the inner axle 20b and stopping it. Is provided.
[0015]
As shown in FIGS. 6 to 8, the tread positioning device 50 includes a cylindrical tubular body 51 and a shaft 52 that is slidably fitted in the tubular body 51. A long hole 53 is opened, and a plurality of positioning holes 54, 54... Are provided on the upper surface of the shaft 52 in the longitudinal direction so as to face the long hole 53. By inserting a pin 55 from above the long hole 53 and inserting it into an arbitrary positioning hole 54, the slide end position of the shaft 52 relative 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.
[0016]
On the other hand, the tread fixing device 60 includes a cylindrical cylindrical body 61, a shaft 62 slidably fitted in the cylindrical body 61, an inverted L-shaped plate 63 provided on the upper portion of the shaft 62, and the like. A long side 63a of the plate 63 is disposed in parallel with the shaft 62, and slidably contacts a guide portion 64 provided integrally with the upper portion of the cylindrical body 61. The short side makes a right angle with the long side 63a. The side 63 b is bolted to one end surface of the shaft 62.
[0017]
The guide portion 64 is provided with an opening hole 65 having a screw portion, and a plurality of fixing holes (baka holes) 66, 66... Are formed in the long side 63a of the plate 63 in the longitudinal direction. Then, when any one of the fixing holes 66 moves above the opening hole 65, a fixing bolt 67 is inserted from above the fixing hole 66 and can be screwed into the opening hole 65. In particular, the guide part 64 is not provided on the upper part of the cylindrical body 61, and an opening 65 having a screw part is provided directly in the cylindrical body 61, and the long side 63 a of the plate 63 is slidable on the upper surface of the cylindrical body 61. You may form so that it may contact. The tread fixing device 60 is also detachably attached to the outer axle 20a of the front axle housing 20 by bolting.
[0018]
Further, a flange-shaped plate 25 is fixed to the inner axle 20b, and one end portion of the plate 25 is fixed to the end surface of the shaft 52 of the tread positioning device 50, and the other end portion of the plate 25 is fixed to the tread fixing device 60. It is fixed to the end face of the shaft 62. Accordingly, the shaft 52 and the shaft 62 slide together as the inner plate 20b moves in the left-right direction.
[0019]
Next, the tread changing procedure will be further described in detail with reference to FIGS. When changing the tread, first, pins or the like are inserted into the locking holes 33a and 33a provided in the left and right knuckle arms 33 and 33, and the rotation of the knuckle arms 33 and 33 is fixed. The tie rod end 45 is loosened or detached from the locking tool 41. For example, when moving the left inner axle 20b, the stopper bolt 48 of the right locking tool 41 is removed, the locking tool 41 is loosened, and the slide rod 46 of the right tie rod end 45 is made free.
[0020]
In this state, when the steering cylinder 36 is driven to move the piston rods 39 to the left, the left tie rod end 45 locked to the left locking tool 41 is pushed to the left, and the left knuckle The left inner axle 20 b is pulled out integrally with the arm 33. Thus, the width of the left side portion of the front axle housing 20 is extended and the tread is enlarged. On the contrary, if the piston rod 39 is moved to the right side, the left inner axle 20b is pulled inward, the width of the left side portion of the front axle housing 20 is reduced, and the tread is reduced.
[0021]
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, the locking tool 41 is relaxed, and the slide rod 46 of the left tie rod end 45 is made free. In this state, if the steering cylinder 36 is driven to move the piston rods 39 to the left or right, the right tie rod end 45 locked to the right locking tool 41 is pushed to the left or right, The right inner axle 20 b is pushed and pulled together 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.
[0022]
As shown in the figure, even when the distance between the end surfaces of the piston rods 39 and 39 and the knuckle arms 33 and 33 is short and it is difficult to attach a member for expanding and contracting the tie rod 49, the axial center of the piston rod 39 The axis of the slide rod 46 of the tie rod end 45 is offset to wrap the piston rod 39 and the tie rod end in parallel, and a telescopic member (in this embodiment, the locking tool 41 and the slide rod 46) is wrapped around this lap portion. By interposing, the length of the tie rod 49 can be expanded and contracted.
[0023]
When the left tread is widened, as shown in FIG. 7A, for example, a pin 55 is inserted into the first positioning hole 54 from the left of the left tread positioning device 50 and the left tread is fixed. The fixing bolt 67 of the device 60 is loosened and removed. In this state, as described above, the rotation of the left and right knuckle arms 33 and 33 is fixed to loosen the right tie rod end 45 from the locking tool 41, and the left inner axle 20b is driven by the steering cylinder 36. Is pulled out to the left, the shaft 52 of the tread positioning device 50 slides in the cylinder 51 and moves to the left, and the shaft 62 of the tread fixing device 60 slides in the cylinder 61 and moves to the left. To do.
[0024]
As shown in FIG. 5B, when the pin 55 inserted into the shaft 52 comes into contact with the left end of the long hole 53, the shaft 52 can no longer slide to the left, and the left inner The movement of the axle 20b stops. Thereafter, when a fixing bolt 67 is inserted into the fixing hole 66 of the tread fixing device 60 and screwed into the opening hole 65, the slide of the shaft 62 is restrained and the tread is fixed.
[0025]
On the other hand, when the left inner axle 20b is pulled to the right to narrow the tread, the shaft 52 can slide to the right when the pin 55 inserted into the shaft 52 comes into contact with the right end of the long hole 53. The movement of the inner axle 20b is stopped. When changing the right tread, the right tread positioning device 50 and the right tread fixing device 60 are operated symmetrically with the above, so that the right portion tread positioning and tread fixing can be easily performed. Can do.
[0026]
In either case of expansion or contraction of the tread, the slide end position of the shaft 52 is changed by changing the insertion position of the pin 55, and tread positioning in several steps can be performed very easily. Although not shown, the pins 55 are inserted into arbitrary two positioning holes 54 provided in the shaft 52 of the tread positioning device 50, respectively, so that the two-stage tread is pin 55. It can be changed alternately without replacement.
[0027]
As shown in FIGS. 1 and 6, the tread positioning device 50 and the tread fixing device 60 are opposed to each other in the front and rear of the front axle housing 20 and are inclined with respect to the horizontal plane of the front axle housing 20. The operator can see from the driver's seat 13 installed at the rear upper side of the front axle housing 20 and can easily visually recognize the position where the tread has been changed while the operator is seated on the driver's seat 13. In addition, when changing the tread, when inserting and removing the pin 55 and attaching / detaching the fixing bolt 67, it is possible to perform the operation while visually observing from diagonally rear rather than through the tire, and workability is improved.
[0028]
Since the tread positioning device 50 and the tread fixing device 60 are detachable from the outer axle 20a of the front axle housing 20, the outer axle 20a is shared by the tread fixing work vehicle and the tread changing work vehicle. can do.
[0029]
It should be noted that the present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.
[0030]
【The invention's effect】
As described in detail in the above embodiment, the present invention is formed to be extendable by inserting inner axles (20b, 20b) slidably into the left and right ends of the center case (20a) . Since the tread positioning device (50, 50) and the tread fixing device (60, 60) are detachably disposed opposite to each other on the left and right sides of the axle housing (20) , the shape of the axle housing is biased to one side. Therefore, the strength can be made uniform. Also, by removing the tread positioning device and the tread fixing device, it is possible to easily make the tread fixing type and the tread changing type. Therefore, the axle housing can be shared by the tread fixing type and the tread changing type, and the cost can be reduced by sharing the parts. Further, a bowl-shaped plate (25, 25) is fixed to the inner axle (20b, 20b), and one end of the plate (25, 25) is attached to the shaft (52, 25) of the tread positioning device (50, 50). 52) and the other end of the plate (25, 25) is fixed to the end surface of the shaft (62, 62) of the tread fixing device (60, 60), so that the inner plate (20b, The shaft (52) and the shaft (62) slide integrally with the movement of 20b) in the left-right direction.
Regardless of whether the tread is expanded or contracted, the slide end position of the shaft (52) is changed by changing the insertion position of the pin (55), so that tread positioning in several steps can be performed very easily. Further, by inserting the pins (55, 55) into arbitrary two positioning holes (54, 54) provided in the shaft (52) of the tread positioning device (50), respectively, a two-stage tread is obtained. The pins (55) can be changed alternately without replacement.
[0031]
According to a second aspect of the present invention, the tread change portion of the axle housing formed to be extendable and tilted is inclined with respect to the horizontal plane, and the tread change portion is disposed so as to be visible from the driver's seat. The tread change position can be easily visually recognized while seated. Also, when inserting and removing the pin 55 and attaching / detaching the fixing bolt 67 when changing the tread, it is possible to perform the work while visually observing obliquely from the rear rather than through the tire, and the workability can be improved. It is an invention that has an effect.
[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 a 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 main parts of a bracket and a tie rod end.
FIG. 6 is a side view of a front axle housing.
7A and 7B show a main part of a tread positioning device and a tread fixing device, where 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, in which 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)

A tread positioning device (50, 50) and a tread fixing device are provided on the left and right and front and rear of an axle housing (20) formed to be slidable by inserting inner axles (20b, 20b) into both left and right ends of the center case (20a). (60, 60) are opposed to each other and are detachably disposed, and the tread positioning device (50, 50) has a cylindrical body (51, 53 ) having a long hole ( 53, 53 ) along the axle housing (20) . 51) and a shaft (52 ) that has a plurality of positioning holes (54, 54...) That slides in the cylinders ( 51 , 51) and passes through the pins (55, 55) together with the long holes (53, 53). , 52) , while the tread fixing device (60, 60) has a cylindrical body (61, 6 ) having an opening hole (65, 65) for inserting the fixing bolt (67, 67). Inverted L having a 1), a plurality of fixing holes for inserting the with fixing bolts (67, 67) the cylindrical body (61, 61) in the slide and the opening hole (65, 65) (66, 66 ...) And a shaft (62, 62 ) with a letter-shaped plate (63, 63) , and a bowl-shaped plate (25, 25) fixed to the inner axle (20b, 20b). Is fixed to the end surface of the shaft (52, 52) of the tread positioning device (50, 50), and the other end of the plate (25, 25) is fixed to the shaft (60, 60) of the tread fixing device (60, 60). 62, 62) . A tread changing device for a work vehicle, characterized in that the tread changing device is fixed to an end face of 62, 62) . The tread positioning device ( 50, 50 ) and the tread fixing device ( 60, 60) are disposed to be inclined with respect to the horizontal plane of the axle housing (20) , and at least the tread positioning device ( 50, 50) is disposed in the driver seat (13 ) tread changing device for a work vehicle that visibly disposed claims 1, wherein the.

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