JPH0750904Y2 - Work vehicle clutch operation structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a work cylinder clutch operating structure provided with a lift cylinder for vertically moving a work device with respect to a traveling machine body and a transmission clutch for the work device. Regarding

[Conventional technology]

As a clutch operating structure of the work vehicle as described above, conventionally, for example, as shown in Japanese Utility Model Laid-Open No. 59-133025,
A sensor for detecting the ground height of the mowing unit (working device) is provided, and if the ground height of the mowing unit is less than or equal to the set value, the mowing clutch (clutch for transmitting the working device) is engaged, and the ground height of the mowing unit is There is a device that automatically controls the reaping clutch so that the reaping clutch is disengaged when becomes larger than the set value.

[Problems to be solved by the invention] According to the above configuration, the mowing clutch is always automatically disengaged when the mowing section is raised and not in operation,
Although it has the effect of increasing power loss due to forgetting to disengage the mowing clutch or improving safety during non-working, it requires a ground height detection sensor and an electric circuit for automatic control to automatically control the mowing clutch. However, there was a problem that it became complicated and increased the cost.

An object of the present invention is to effectively utilize a conventional mechanism to control a work device transmission clutch without complicating the structure.

[Means for Solving the Problems]

According to a characteristic configuration of the present invention, a clutch cylinder for operating the transmission clutch is provided, and a part of the rising pressure oil supplied from the control valve to the lift cylinder is taken out and guided to an oil passage to the clutch cylinder. An oil discharge means for forming a port for discharging pressure oil for disengaging the clutch cylinder in the middle of the stroke of the lift cylinder, and for permitting oil discharge from the oil passage when the control valve is switched to the lowered position. Is provided.

[Action]

According to the above configuration, when the lift cylinder operates from the stroke end on the working device lower side to the work device rising side for a set stroke or more, a part of the working device raising pressure oil is taken out from the hydraulic cylinder take-out port of the lift cylinder. The supplied clutch cylinder is actuated to the clutch disengagement side. Further, when the lift cylinder operates to lower the working device, the clutch cylinder is drained and the transmission clutch is engaged and is ready for operation.

[Effect of device]

Therefore, according to the present invention, a relatively simple modification is made to the conventional hydraulic device for lifting and lowering the working device.
The work operation transmission clutch can be automatically operated with a simple and inexpensive structure.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows a front part of an all-crane throw-in type combine, which is an example of the work vehicle according to the present invention. At the front part of this combine, a mowing section (1) as a working device is arranged so as to be able to move up and down. This reaping part (1) is a raising device (2) for raising the planted culm sown by the weeding tool (4) with a lateral feed locking claw, and the root end of the raised planted culm. A cutting device (5) for cutting the cuttings, a rear conveyance device (3) for nipping and conveying the cutting grain culms rearward in an upright posture, and an auger (6) for laterally joining the cut grain culm tips to the cutting width intermediate portion. And a feed case (9) in which a pre-treatment head section (7) provided with (4) and a feeding and conveying device (9) that conveys the grain culm tip side portion inherited from (6) toward a threshing device (not shown) are installed. 10) and is driven up and down by a lift cylinder (8).

FIG. 1 is a link diagram showing the correlation between the drive means of the lift cylinder (8) and the power connection / disconnection means to the mowing section (1), and (11) in the figure shows the engine power as the mowing section ( 1)
Mowing clutch as a transmission clutch, which is transmitted to (1
2) is an operating lever for engaging and disengaging the clutch, (13) is a control valve that controls the operation of the lift cylinder (8), and
(14) is a single-acting type clutch cylinder for forcibly disengaging the reaping clutch (11).

The reaping clutch is configured as a tension clutch having a tension arm (16) that is biased toward the clutch entry side by a spring (15), and the tension arm (16) can be toggled between two positions and held. The operation lever (12) is linked via a wire (17) so that the clutch can be engaged by loosening the wire (17) and the clutch can be disengaged by pulling the wire (17). Has become.

A port (18) formed in the middle of the stroke of the lift cylinder (8) and the clutch cylinder (14) are connected by an oil passage (20) with a throttle (19) interposed, and a control valve (13) is at a raised position ( UP), the lift cylinder (14) expands by a set value or more, and the port communicates with the high-pressure hydraulic chamber, that is, when the reaper (1) is driven upward by a set height or more, the lift cylinder (8). ) A part of the pressure oil supplied to the clutch cylinder (14) is guided through the port (18) and the oil passage (20) to forcibly disengage the reaping clutch (11) in the engaged state. It is supposed to be done.

The throttle (19) is set to a throttle amount such that the drive pressure of the lift cylinder (8) can maintain the pressure required to raise the cutting section. Further, when the tension arm (16) is operated in the clutch disengaging direction along with the extension operation of the clutch cylinder (14), the wire (17) and the tension arm (1)
6) A spring (21) assembled by applying initial compression to the linking part with
Will bend.

When the reaper (1) is raised to the desired position and the control valve (13) is returned to the neutral position (N), the reaper (1) stops and the pressure oil in the clutch cylinder (14) is trapped. The disengaged state of the clutch (11) is maintained.

Further, when the control valve (13) is switched to the lowered position (DN) and the mowing unit (1) is lowered by its own weight, the oil passage (20) is accompanied by the bypass oil discharge passage (22) to the clutch cylinder. The oil is discharged from (14), the clutch cylinder (14) is shortened, and the reaping clutch (11) is closed again by the spring (15).

Further, the bypass oil discharge passage (22) is provided with a throttle (23) for limiting the oil discharge speed, and the mowing unit (1)
It is designed so that the cutting clutch (11) does not enter too rapidly with the lowering of.

The clutch cylinder (14) and the tension arm (16) are linked to each other through a long hole (24), and the operation lever (12) is fixed in a state where the clutch cylinder (14) is fixed in a shortened state. The tension arm (16) can be operated to disengage the clutch.

It should be noted that reference numerals are added to the claims of the utility model for convenience of comparison with the drawings, but the present invention is not limited to the structure of the accompanying drawings by the entry.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings show an embodiment of a clutch operating structure for a work vehicle according to the present invention, and FIG. 1 is a linkage diagram of a lift cylinder and a transmission clutch. FIG. 2 is a front side view of the all culm throw-in type combine. (1) …… Working device, (8) …… Lift cylinder, (1
1) …… Transmission clutch, (13) …… Control valve, (14) …… Clutch cylinder, (18) …… Port,
(20): Oil passage, (A): Traveling vehicle.

Claims (1)

[Scope of utility model registration request] 1. A work vehicle clutch provided with a lift cylinder (8) for vertically moving a working device (1) with respect to a traveling machine body (A), and a transmission clutch (11) for the working device (1). In the operating structure, a clutch cylinder (14) for operating the transmission clutch (11) is provided, and a part of the rising pressure oil supplied from the control valve (13) to the lift cylinder (8) is taken out. A port (18) for leading out pressure oil for guiding the oil passage (20) to the clutch cylinder (14) to disengage the clutch cylinder (14) is formed in the middle of the stroke of the lift cylinder (8). In addition, the clutch operating structure for the working vehicle is provided with an oil draining means that allows oil draining from the oil passage (20) when the control valve (13) is switched to the lowered position.