JP4422267B2 - Vehicle tread changing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle tread changing device that can change treads of left and right wheels.
[0002]
[Prior art]
Conventionally, some vehicles such as tractors have been provided with a tread changing device that can change the tread of the left and right wheels. Such a tread changing device is, for example, slid right and left of the fixed axle case. The tread of the left and right wheels can be changed by inserting the moving-side axle case and sliding the sliding-side axle case with respect to the fixed-side axle case. The sliding-side axle case is slid by inserting a hydraulic cylinder between the sliding-side axle case and the fixed-side axle case, and expanding and contracting the hydraulic cylinder. Also, by performing feedback control based on the actual tread dimensions, the changed tread dimensions are kept constant, or a control valve is provided in the hydraulic circuit of the hydraulic cylinder, and the tread dimensions are kept constant by this control valve. I was doing.
[0003]
[Problems to be solved by the invention]
However, as described above, in a vehicle having a tread changing device, since the tread changing means is a hydraulic device such as a hydraulic cylinder, the device is large and complicated and expensive. Further, since feedback control or a control valve is provided in order to keep the changed tread constant, the apparatus is further complicated and expensive. Furthermore, unlike the structural member used for the vehicle of the specification which does not have a tread change apparatus, the component part of an axle part has become many only for vehicles which have a tread change apparatus.
[0004]
[Means for Solving the Problems]
The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.
[0005]
According to the first aspect of the present invention, in the vehicle tread changing device that can change the tread of the left and right rear wheels (RW), a rack (10c) is formed on a part of the outer peripheral surface of the rear axle (10) that is an axle. A worm (31a) that meshes with the rack (10c) is provided in parallel to the flange (28) of the rear wheel (RW) that fits outside the rear axle (10), and the worm (31a) is rotated. Is a manual operation, and an operation handle (32) as an operation portion of the worm (31a) is provided outside the flange portion (28) supporting the rear wheel (RW), and the flange portion (28) has a worm ( An operation shaft (31) provided with 31a) is rotatably fitted, and the operation handle (32) is pivotally supported at the outer end of the operation shaft (31) so as to be rotatable in a standing state and a retracted state. When installed and standing By rotating the operation handle (32), the operation shaft (31) and the worm (31a) are rotated and the tread can be changed. When in the retracted state, the operation handle (32) interferes with the flange portion (28). The operation shaft (31) cannot be rotated, and the operation handle (32) of the worm (31a) is also used as a detent member for the worm (31a) .
[0006]
According to a second aspect of the present invention, in the vehicle tread changing apparatus according to the first aspect, the second shaft (10b), which is the rack (10c) forming portion, of the rear axle (10) is moved from the rack (10c) forming portion. Is formed separately from the first shaft (10a) of the inner portion, and the second shaft (10b) can be attached to and detached from the first shaft (10a) .
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described.
[0008]
1 is a plan sectional view showing a rear axle portion in a minimum tread state where the tread changing apparatus of the present invention is provided, FIG. 2 is a plan sectional view showing a rear axle portion in a maximum tread state, and FIG. 3 is also a rear axle portion. FIG.
[0009]
A vehicle tread changing apparatus according to the present invention will be described. As shown in FIGS. 1 and 3, a rear axle case 9 of a vehicle such as a tractor is fixed to a transmission case M, and a differential yoke shaft 15 that enters the rear axle case 9 from the transmission case M has a planetary gear. Via a speed reducer 16, the rear axle 10, which is an axle that supports the rear wheel RW, is linked and connected.
[0010]
The planetary reduction device 16 has a sun gear 17 integrally formed at the outer end of the differential yoke shaft 15, and a planetary gear 19 rotatably supported by a holder 18 is disposed around the sun gear 17. A ring gear 20 attached to the rear axle case 9 is disposed outside the planetary gear 19 and meshes with the planetary gear 19.
[0011]
The rear axle 10 includes a first shaft 10 a housed in the rear axle case 9 and a second shaft 10 b that protrudes outside the rear axle case 9. The first shaft 10a is supported by the rear axle case 9 via bearings 23 and 24, and the holder 18 is fixed to the inner end of the first shaft 10a. The second shaft 10b is detachably attached to the first shaft 10a, and can rotate integrally with the first shaft 10a. The wheel member 29 of the rear wheel RW is fixed to the second shaft 10b. The flange portion 28 is slidably fitted.
[0012]
Further, a rack portion 10c is formed in a part of the outer peripheral surface of the second shaft 10b in the axial direction, and a key groove 10d is formed at a position facing the rack portion 10c on the outer peripheral surface. The key groove 10d is fitted with a protrusion 28a formed on the inner peripheral surface of the flange portion 28, so that the flange portion 28 does not rotate with respect to the second shaft 10b, that is, the flange portion 28 and the second shaft. 10b is configured to rotate integrally.
[0013]
Further, an operating shaft 31 on which a worm 31a is formed is rotatably fitted to the flange portion 28. The operating shaft 31 is disposed on the outer periphery of the second shaft 10b, and the worm 31a and the second shaft 10b. The rack part 10c formed in this is meshed. An operation handle 32 is attached to the outer end portion of the operation shaft 31, and the operation shaft 32 is configured to rotate by the operation handle 32. The operation handle 32 is rotatably attached to the operation shaft 31, and the operation handle 32 shown by a solid line in FIG. 1 is an operation handle 32 in a state where it is turned outward to stand and is indicated by a two-dot chain line. The illustrated operation handle 32 is an operation handle 32 that is turned inward to be in a stored state.
[0014]
Then, when the holding portion 32a of the operation handle 32 in a state of being turned upright is held and the operation handle 32 is rotated, the operation shaft 31 is rotationally driven. When the operation shaft 31 is driven to rotate, the worm 31a of the operation shaft 31 meshes with the rack portion 10c formed on the second shaft 10b of the rear axle 10, and therefore, the flange that supports the operation shaft 31. The portion 28 moves inward or outward with respect to the second shaft 10b depending on the rotational drive direction of the operation shaft 31.
[0015]
In this way, the operation shaft 31 is rotated by manually rotating the operation handle 32 in the standing state from the left and right outer sides of the rear wheel RW, and the rear wheel RW fixed to the flange portion 28 is moved inward or outward. The tread of the left and right rear wheels RW is changed by moving. For example, when the operation shaft 31 is rotated in the direction in which the rear wheel RW is moved outward by the operation handle 32 from the state where the tread is minimum as shown in FIG. 1, the rear wheel until the maximum tread state shown in FIG. The RW can be moved outward.
[0016]
After the operation shaft 31 is rotationally driven and the tread is changed, the operation handle 32 is rotated inward so as to be accommodated within the substantially left-right width of the flange portion 28. The operation handle 32 rotated inward is locked by a pin member 34 provided on a bracket 33 fixed to the flange portion 28 so as to prevent outward rotation and hold the storage state. The pin member 34 is provided so as to be slidable with respect to the bracket 33. By sliding the pin member 34 to a position where the operation handle 32 is not locked, the operation handle 34 is turned upright. It is possible to move.
[0017]
The operation shaft 31 can be rotated when the operation handle 32 is in the standing state, but when the operation handle 32 is in the retracted state, the operation handle 32 interferes with the flange portion 28, and the operation shaft 31 is Cannot rotate. In other words, the operating handle 32 in the stored state is also used as a detent member for the operating shaft 31.
[0018]
Further, a scale 38 is engraved on the outer peripheral surface of the second axle 10b of the rear axle 10. For example, the tread dimension can be confirmed by reading the position of the inner end of the flange portion 28 with the scale 38. ing.
[0019]
As described above, in this tread changing device, the operation shaft 31 having the worm 31a is provided on the flange portion 28 of the rear wheel RW fitted to the second shaft 10b of the rear axle 10, and meshed with the worm 31a. The rack 10c to be formed is formed on the second shaft 10b and the operation shaft 31 is rotationally driven to move the rear wheel RW to the left and right to change the tread. When a vehicle having a specification that is not provided is changed to a specification having a tread changing device, it is only necessary to replace the rear wheel RW such as the rear axle 10 and the flange portion 28, and the specification can be easily changed. Further, the tread changing device can be configured with a simple and inexpensive structure as compared with the case where the tread change is performed by sliding the sliding side axle case inserted into the fixed side axle case. Further, since the tread is changed by the rotation of the worm 31a meshing with the rack 10c, the tread size can be easily finely adjusted.
[0020]
Further, since the operation shaft 31 is configured to be rotationally driven manually by the operation handle 32, the tread changing device can be configured more easily and inexpensively. Since the operation handle 32 is provided at the rear wheel RW, the tread dimensions can be easily confirmed during the tread changing operation, and the tread can be adjusted with high accuracy.
[0021]
Further, since the operation handle 32 is also used as a detent member for the operation shaft 31, it is not necessary to provide a separate detent member for the operation shaft, the number of parts can be reduced, and the tread changing device can be made compact. Can be configured. By using the operation handle 32 as the operation portion of the operation shaft 31, tread adjustment can be performed with a simple operation and a small operation force.
[0022]
In the rear axle 10, the first shaft 10 a housed in the rear axle case 9 and the second shaft 10 b in which the rack 10 c is formed and the rear wheel RW including the operation shaft 31 and the like are fitted are separated. Since the second shaft 10b is detachably attached to the first shaft 10a, the vehicle having the specification without the tread changing device is changed to the specification having the tread changing device. Since only the part of the second shaft 10b on the rear wheel RW side needs to be replaced, the specification can be easily changed and the number of replacement parts can be reduced, so the specification can be changed at low cost. it can.
[0023]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
According to a first aspect of the present invention, there is provided a vehicle tread changing apparatus capable of changing the treads of the left and right rear wheels (RW). At the same time, a worm (31a) that meshes with the rack (10c) is provided in parallel to the flange (28) of the rear wheel (RW) that fits outside the rear axle (10), and the worm (31a) The rotation operation is manual operation, and an operation handle (32) which is an operation portion of the worm (31a) is provided outside the flange portion (28) supporting the rear wheel (RW). An operation shaft (31) provided with a worm (31a) is rotatably fitted, and the operation handle (32) is rotatably mounted on the outer end of the operation shaft (31) in a standing state and a retracted state. Pivotally mounted, standing up The operation handle (32) is rotated to rotate the operation shaft (31) and the worm (31a), and the tread can be changed. When in the retracted state, the operation handle (32) is connected to the flange portion (28). Interfering, making it impossible to rotate the operating shaft (31), and the operation handle (32) of the worm (31a) is also used as a detent member for the worm (31a) and does not have a tread changing device. When changing the specification vehicle to a specification having a tread changing device, it is only necessary to replace the rear axle and the rear wheel, and the specification change can be easily performed.
In addition, the tread changing device can be configured with a simple and inexpensive structure as compared with the case where the tread change is performed by sliding the sliding side axle case inserted into the fixed side axle case.
Further, since the tread is changed by the rotation of the worm meshing with the rack, the tread size can be finely adjusted easily.
[0024]
Further, since the rotation operation of the worm is a manual operation and the operation portion of the worm is provided at the outer end portion of the wheel, the tread changing device can be configured more simply and inexpensively.
And since this operation part is provided in the outer side edge part of the axle shaft, it is possible to easily check the tread dimensions at the time of tread changing work, and it becomes possible to adjust the tread with high accuracy.
[0025]
Furthermore, since the worm operating part is also used as the worm detent member, there is no need to provide a separate detent member for the operation shaft, the number of parts can be reduced, and the tread changing device can be made compact. can do.
In addition, by configuring the operation portion as a handle-like member, it is possible to perform tread adjustment with a simple operation and a small operation force.
[0026]
According to a second aspect of the present invention, in the vehicle tread changing apparatus according to the first aspect, the second shaft (10b), which is the formation portion of the rack (10c) of the rear axle (10), is formed as the rack (10c). Since the first shaft (10a) at the inner side of the part is formed separately from the first shaft (10a), the second shaft (10b) can be attached to and detached from the first shaft (10a). When changing to a specification having a tread changing device, it is only necessary to replace the axle rack forming part, which is the axle on the side where the rear wheel is attached, and the specification can be easily changed. Since the number of replacement parts is small, the specifications can be changed at low cost.
[Brief description of the drawings]
FIG. 1 is a plan sectional view showing a rear axle portion in a minimum tread state where a tread changing apparatus according to the present invention is provided.
FIG. 2 is a plan sectional view showing the rear axle portion in the same maximum tread state.
FIG. 3 is a side sectional view showing the rear axle portion.
[Explanation of symbols]
M transmission case RW rear wheel 9 rear axle case 10 rear axle 10a first shaft 10b second shaft 10c rack 28 flange portion 31 operation shaft 31a worm 32 operation handle

Claims (2)

In a vehicle tread changing apparatus that can change treads of left and right rear wheels (RW), a rack (10c) is formed on a part of an outer peripheral surface of a rear axle (10) that is an axle, and the rack (10c) A worm (31a) meshing with the rear axle (10) is provided in parallel to the flange (28) of the rear wheel (RW), and the worm (31a) is rotated manually. An operation handle (32), which is an operation portion of the worm (31a), is provided outside the flange portion (28) that supports the rear wheel (RW), and the flange portion (28) is provided with the worm (31a). The shaft (31) is rotatably fitted, and the operation handle (32) is pivotally attached to the outer end portion of the operation shaft (31) so as to be rotatable between the standing state and the retracted state. The operation handle (3 ) To rotate the operation shaft (31) and the worm (31a), and the tread can be changed. When in the retracted state, the operation handle (32) interferes with the flange portion (28), and the operation shaft A tread changing apparatus for a vehicle characterized in that the rotation of (31) is impossible, and the operation handle (32) of the worm (31a) is also used as a detent member for the worm (31a) . 2. The vehicle tread changing apparatus according to claim 1, wherein a second shaft (10 b) that is a forming portion of the rack (10 c) of the rear axle (10) is a first portion in an inner portion of the rack (10 c) forming portion. A tread changing apparatus for a vehicle, which is formed separately from the shaft (10a), and the second shaft (10b) can be attached to and detached from the first shaft (10a) .

Images