JPH0694090A - Hydraulic tension clutch of farm working vehicle - Google Patents

Abstract

PURPOSE:To dispense with any tension adjustment required due to belt elongation by enabling a tension arm of a belt tension clutch to a working unit to carry out a clutch-on operation by means of a pressure oil supply to a hydraulic cylinder. CONSTITUTION:A charge relief valve 28 installed in a charging hydraulic circuit of a hydrostatic type continuously variable transmission 12 is used jointly with a setting pressure adjusting relief valve, pressing three tension arms 16a, 17a and 20a with constant pressure, and an operating hydraulic cylinder 29 is connected to a feed chain interlocking clutch 19 in a hydraulic circuit to a pretreating belt tension clutch 16, and in this case, a two-position selector type operating valve 30 automatically operating both these clutches 16 and 19 with the ascent of more than the specified value of a reaping pretreatment unit 5 in time of turning a levee edge is installed at the more upper part than a route branch spot leading to the hydraulic cylinder 29. Therefore pressing force to the tension arm is always keepable constant irrespective of belt elongation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operating structure for a belt tension clutch of a working vehicle such as a combine or a lawn mower.

[0002]

2. Description of the Related Art A conventional combine harvester, which is an example of a work vehicle, has a belt tension clutch of a harvesting pretreatment device or a threshing device as a working device of a combine harvester. The tension arm and the operating lever are linked to each other via a Bowden wire, a push-pull wire, or the like so as to be operable.

[0003]

The tension load changes due to the elongation of the belt and the operation wire, and it is necessary to adjust the urging force of the spring for suppressing the slip of the belt. In addition, in the arrangement of the wire, a small bend cannot be taken in a place where the route is complicated, that is, if the curvature of the operation wire is increased, the frictional resistance between the outer wire and the inner wire increases and the lever operation becomes heavy, If the lever ratio is increased in order to avoid this, a large space is required for rotating the long operation lever, and there is the inconvenience that the degree of freedom in design is low as a whole. An object of the present invention is to eliminate the above-mentioned drawbacks by devising a structure for operating a tension arm of a belt tension clutch.

[0004]

The characteristic structure of the present invention for achieving the above object is that the tension arm of the belt tension clutch for the working device can be engaged with the clutch by supplying pressure oil to the hydraulic cylinder. is there.

[0005]

With the tension pressure adjusting valve such as the relief valve, the pressing force against the tension arm can always be made constant regardless of the elongation of the belt. Then, when arranging the pipes, at a place where the routes are complicated, it is possible to rapidly change the route by using a right-angle joint or an elbow type joint. Further, the on / off of the belt tension clutch can be operated via an operation tool such as an ON / OFF two-position switching type cock.

[0006]

As a result of the above construction, it is not necessary to adjust the tension by stretching the belt, and the degree of freedom in designing the operating structure of the belt tension clutch is increased. or,
The space for operating the belt tension clutch on / off control device is small, and the control panel can be made compact.

[0007]

Embodiments of the present invention will be described below with reference to a combine, which is an example of a work vehicle. As shown in FIG. 3, a maneuvering unit 2, a threshing device 3, and a Glen tank 4 are mounted on a machine frame provided with a crawler traveling device 1, and a cutting pretreatment device 5 can be lifted and lowered in a front part of the traveling machine body. It is provided to form a combine. The pre-mowing device 5 is a raising device 6 for raising planted culms, a reaping device 7 for reaping the root part of the raised culms, and delivering the cut culms to the feed chain 3a of the threshing device 3. The vertical transfer device 8 is provided, and the entire pre-mowing device 5 is configured to be vertically movable around the horizontal axis X by the expansion / contraction operation of a manually operated hydraulic cylinder 9 installed between the cutting device and the traveling machine body. ing. The grain tank 4 is equipped with a tank 4a for storing the grains conveyed from the threshing device 3 and a fried device 4b for discharging the grains in the tank 4a to the outside. As shown in FIG. 2, it is provided with a bottom conveying screw 4c for conveying the grains in the tank 4a toward the fried device 4b side, and is configured to be interlockable with the conveying screw 4d of the fried device 4b. Explaining the transmission system, the output of the engine 10 is transmitted to the input shaft 14 of the transmission in the traveling mission case 13 via the traveling belt tension clutch 11 and the hydrostatic continuously variable transmission 12. Thus, the crawler traveling device 1 can be driven. Then, the cutting pretreatment device 5 can be driven via the PTO shaft 15 branched and transmitted from the hydrostatic stepless transmission 12 and the pretreatment belt tension clutch 16. And the threshing device 3 from the engine 10 via the threshing belt tension clutch 17
Is configured to be driven. In addition, the feed chain 3 a of the threshing device 3 includes an articulating clutch 19 in the gear case 18.
The power can be shut off independently via. The bottom transport screw 4c of the Glen tank 4 can be driven from the engine 10 via the Glen tank belt tension clutch 20. The belt tension clutches 16, 17, and 20 for the pretreatment, the threshing, and the Glen tank are configured to be hydraulically operable. Next, the hydraulic operation system of each belt tension clutch 16, 17, 20 will be described. As shown in FIG. 1, from the charge pump 20 of the hydrostatic continuously variable transmission 12 to the traveling device 1 to the two-position switching type cocks 21, 22, 23 as the respective operating valves,
And each hydraulic cylinder 24, 2 for incorporating the return spring
Belt tension clutches 16, 1 through 5, 26
The 7, 20 tension arms 16a, 17a, 20a are configured to be operable. The charge relief valve 28 provided in the charging hydraulic circuit of the hydrostatic continuously variable transmission 12 is attached to the tension arms 16a, 17a, 2a.
It is also used as a relief valve for adjusting the set pressure for pressing 0a with a constant pressure.

Further, a hydraulic cylinder 29 for operating the feed chain articulating clutch 19 is connected in the hydraulic circuit to the pretreatment belt tension clutch 16 to interlock with the drive / stop of the cutting pretreatment device 5. The feed chain 3a of the threshing device 3 is configured to be driven and stopped, and further, the swivel turning is performed on the flow path upper side than the branch point of the hydraulic cylinder 29 for the feed chain articulating clutch 19. Pretreatment device 5
The belt tension clutch 16 for pretreatment and the articulation clutch 1 for feed chains with the increase of
A two-position switching type operation valve 30 for automatically turning off the 9 is provided. The two-position switching type operation valve 30 is provided with a cam 3 provided on the swing support shaft of the pre-mowing treatment device 5.
1 is operable.

[Other Embodiments] Tension arms 16a, 17a of belt tension clutches 16, 17, 20
The charge pump 20 of the hydrostatic stepless transmission 12 was used to operate the hydraulic pressure control valve 20a via the hydraulic cylinders 24, 25, 26. However, a dedicated pump and a relief valve for adjusting the tension pressure are provided. You may. Further, the present invention may be applied to a riding lawn mower so that the tension arm of the belt tension clutch for the mower equipped can be operated by a hydraulic cylinder.

It should be noted that although reference numerals are given in the claims for convenience of comparison with the drawings, the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a hydraulic system.

[Fig. 2] Schematic diagram of transmission system

FIG. 3 is a side view of the entire combine.

[Explanation of symbols]

 5 Working device 16 Belt tension clutch 16a Tension arm 24 Hydraulic cylinder

Claims (1)

[Claims] 1. A hydraulic tension for a working vehicle, wherein a tension arm (16a) of a belt tension clutch (16) for a working device (5) is operable to be engaged by supplying pressure oil to a hydraulic cylinder (24). clutch.