JPH0649127Y2 - Lift arm structure of offset tractor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a lift arm structure for a so-called off-set tractor in which the center of the machine body and the center of the tread are eccentric to the left and right sides.

[Problems to be Solved by Prior Art and Invention] Generally, in this type of off-set tractor, since the center of the machine body is eccentric with the center of the tread, the left and right lift arms are considerably large so that the tips are aligned with the center of the tread. It has to be bent, which results in strength problems. Therefore, conventionally, as shown in Japanese Utility Model Application Laid-Open No. 57-187286, the hydraulic shaft to which the base end of the lift arm is attached is extended to the center of the tread, but this one still has a large bending amount of the lift arm. It is not allowed, and there is a drawback that a member for supporting the extended hydraulic shaft base end portion is separately required and the structure becomes complicated.

[Means for Solving Problems] In view of the above circumstances, the present invention was devised with the object of providing a lift arm structure for an offset type tractor capable of eliminating these drawbacks. In an offset type tractor in which the center of the machine body is eccentric from the center of the tread, in order to provide lift arm base end parts at both ends of the hydraulic shaft extending from the hydraulic case arranged at the center of the machine body, one end of the hydraulic shaft is moved downward to the driver's seat. It is characterized in that it is extended so that it can be supported by the driver's seat support member.

With this configuration, the present invention can extend the hydraulic shaft to the lower portion of the driver's seat to reduce the amount of bending of the lift arm, and can also support the extended end of the hydraulic shaft with the supporting member of the driver's seat. It was made possible.

[Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 denotes a traveling machine body of an agricultural tractor, in which the engine part 2 of the agricultural tractor 1 is eccentric to the left side of the machine body, a hydraulic case 3 is arranged behind it, and a right side driver seat 4 of the hydraulic case 3 is They are arranged in a so-called offset type.
The driver's seat 4 is attached to a seat bracket 6a fixed to the upper end of a seat support 6 protruding from a rear axle case 7 for the right rear wheel.

The hydraulic case 3 is provided with a hydraulic shaft 5 in the left-right direction, and the left end of the hydraulic shaft 5 extends to the lower portion of the driver's seat 4 beyond the center of the tread, and pivots on the seat support portion 6. Freely supported. The base ends of the left and right lift arms 8 are integrally fixed to the left and right ends of the hydraulic shaft 5, respectively.

In the figure, 9 is a lower link, 9a is a lift rod, 10 is an upper link, 11 is a rear wheel, 12 is a front wheel, and 13 is a steering wheel.

In the embodiment of the present invention configured as described above, the left and right lift arms 8 swing up and down due to the rotation of the hydraulic shaft 5 associated with the expansion and contraction of the hydraulic cylinder in the hydraulic case 3. Driver's seat 4 with the left end crossing the center of Toledo
Has been extended to the lower side of. As a result, the left and right lift arms 8 can be mounted on an off-set tractor whose center of the machine body is eccentric from the center of the tread, but its bending amount can be made as small as possible and the strength problem can be sufficiently covered. become. Moreover, since the left end of the hydraulic shaft 5 extends to the lower portion of the driver's seat 4 in this structure, the seat support portion 6 for supporting the driver's seat 4 is used to support the extended end.
Can be used to support the structure, and therefore, the supporting member which has been conventionally required can be eliminated and the structure can be simplified.

When the left end of the hydraulic shaft 5 is extended to the lower portion of the driver's seat 4 as described above, the upper movement distribution range of the lift arm 8 on the driver's seat 4 side may be narrowed by coming into contact with the driver's seat 4. However, in such a case, the lift arm 8 may be curved downward as shown in FIG.

[Effects and Effects] In short, since the present invention is constructed as described above, the hydraulic case is arranged in the center of the machine body which is eccentric to one side from the center of the tread, and the driver's seat is biased to the other side. However, the lift arm provided at one end of the hydraulic shaft is provided at the tip of the hydraulic shaft that extends beyond the center of the tread and penetrates the support member of the driver's seat. The base end of the lift arm on this side is located on the other side of the driver's seat support member, which allows the amount of bending to be reduced, thereby providing sufficient strength.

Moreover, the hydraulic shaft that extends long beyond the center of the tread is supported in a state of penetrating the driver's seat supporting member, so that a dedicated supporting member can be eliminated and the number of parts can be reduced. This can contribute to simplification of the structure.

[Brief description of drawings]

The drawings show an embodiment of an offset tractor and lift arm structure according to the present invention. FIG. 1 is an overall plan view, FIG. 2 is a side view of the same, and FIG. FIG. 4 is a side view of an essential part when the shape of the lift arm is curved downward. In the figure, 1 is an agricultural tractor, 4 is a driver's seat, 5 is a hydraulic shaft, 8
Are left and right lift arms.

Claims (1)

[Scope of utility model registration request] 1. An off-set type tractor in which the center of the machine body is eccentric to one side of the center of the tread and the driver's seat is eccentric to the other side of the center of the tread. To provide a lift arm base end at both ends of the hydraulic shaft that extends in the left-right direction, extend one end of the hydraulic shaft on the driver's side beyond the center of the tread to support the driver's seat supporting member. A lift arm structure for an offset tractor, characterized in that a lift arm is provided at the penetrating tip.