JPH0115287Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a locking device for a working machine descending speed adjusting lever that adjusts the descending speed of a working machine that is connected to a tractor and moves up and down.

Conventionally, the lever for adjusting the lowering speed of the work equipment installed on the body of a tractor is generally rotated back and forth along a lever guide, and by rotating it back and forth, the hydraulic pressure is adjusted to discharge oil from the hydraulic cylinder. The opening of the opening adjustment valve in the circuit is adjusted, the amount of oil discharged from the hydraulic cylinder is controlled, and the lowering speed of the working machine connected to the tractor and raised and lowered is adjusted. For safety reasons, a locking device is provided to lock the working machine lowering speed adjusting lever at a position where the hydraulic circuit is closed, thereby stopping the lowering of the working machine. There are various types of such locking devices, and typical ones include attaching a fixing plate to the lever guide, and fixing the work equipment lowering speed adjusting lever in a direction perpendicular to the direction of reciprocating rotation operation. Although there are devices that are configured to be rotatable and are locked to a locking portion, they have drawbacks such as an increased number of parts, which requires time and effort to assemble, and a complicated structure.

This invention was devised in view of the above points, and the object is to provide a lever lock device for adjusting the lowering speed of a tractor work equipment, which is simple in structure and lock operation, and can provide a reliable locking state. .

This idea is based on a long groove that runs along the reciprocating rotation direction of the work equipment lowering speed adjustment lever that is provided on the body of the tractor so that it can freely rotate in one direction, and a notch that is cut out laterally in a part of this long groove. A lever guide with a guide groove formed therein is provided, and while the work equipment lowering speed adjustment lever is inserted into the guide groove, the lever guide is moved to a position where the notch engages with the work equipment lowering speed adjustment lever and away from the work equipment lowering speed adjustment lever. Normally, the lever guide is fixed at a position where the notch part is away from the work equipment lowering speed adjustment lever, and the work equipment lowering speed adjustment lever is The descending speed of the work equipment is adjusted by reciprocating the work equipment by rotating it back and forth along the long groove, and the notch engages with the work equipment descending speed adjustment lever located at the position where the lever guide is moved and the hydraulic circuit is closed, and the lever is moved at that position. By fixing the guide, the working machine lowering speed adjusting lever can be locked with the hydraulic circuit closed, and the lowering of the working machine can be stopped.

An embodiment of this invention will be described based on the drawings. A lever support 1 is fixed to the body of the tractor (not shown), and a bolt 2 welded to the lever support 1 has a lowering speed of the work equipment, which rotates back and forth in the front and rear directions using the bolt 2 as a fulcrum. The adjustment lever 3 is supported by a nut 4 while being fixed in its movement in the left and right direction. A rod 5 and a lever 6 are sequentially connected to the lower end of the work equipment lowering speed adjustment lever 3, and the lever 6 is a hydraulic cylinder of a hydraulic system (not shown) that raises and lowers the work equipment (not shown) connected to the machine body. The opening control valve (not shown) is connected to an opening adjustment valve (not shown) provided in a hydraulic circuit (not shown) that discharges oil from a hydraulic circuit (not shown). A support plate 7 is fixed to the upper part of the lever support 1 by bolts 8, and a lever guide 9 whose front and rear edges are bent downward is attached to the upper part of the support plate 7, and the bent portions 10 of the lever guides 9 are attached to the support plate 7. It is tightened and fixed with butterfly bolts while engaging both front and rear edges of the. Note that the bolt hole 12 of the lever guide 9 through which the butterfly bolt 11 is inserted is an elongated hole that is long in the left-right direction. The lever guide 9 has a long groove 13 which is long in the front and back direction and this long groove 1.
Notch 1 cut out on the right side in the front part of 3
A guide groove 15 consisting of 4 is formed, and an elongated hole 16 formed in the support plate 7 and having approximately the same length as the elongated groove 13 is inserted through the guide groove 15 to adjust the descending speed of the working machine. A lever 3 is extended upward.

In such a configuration, the lever guide 9 is usually fixed at a position where the long groove 13 faces above the long hole 16, and the work equipment lowering speed adjustment lever 3 is fixed in the position where the long groove 13 faces above the long hole 16.
and the elongated hole 16, the opening control valve is opened and closed by the interlocking lever 6, and the amount of oil discharged from the hydraulic cylinder is controlled to lower the work equipment at a desired speed. .

When fixing the work equipment in a raised position,
When the work implement lowering speed adjusting lever 3 is pushed forward, the opening adjustment valve is closed, the discharge of oil from the hydraulic cylinder is cut off, and the lowering of the work implement is stopped. While keeping the work equipment lowering speed adjustment lever 3 tilted forward, loosen the butterfly bolt 11, slide the lever guide 9 to the left, engage the notch 14 with the work equipment lowering speed adjustment lever 3, and lower the butterfly. Tighten bolt 11. As a result, the working machine lowering speed adjusting lever 3 is in a locked state in which reciprocating rotational movement is prevented, and the working machine is fixed at the raised position.

In this way, the work machine lowering speed adjustment lever 3 for fixing the work machine in the raised position can be locked by the simple operation of loosening the wing bolt 11, sliding the lever guide 9, and tightening the wing bolt 11 again. bending part 1 of lever guide 9
Since the lever guide 9 is engaged with both front and rear edges of the support plate 7, the lever guide 9 can be easily slid. Moreover, the lever guide 9 is necessary as a guide when operating the work equipment lowering speed adjustment lever 3 in a reciprocating manner.
There is no need to provide a separate lock member to serve as the lock member, and the number of parts can be reduced. Further, the work equipment lowering speed adjustment lever 3 can be locked by sliding the lever guide 9 only when the work equipment lowering speed adjustment lever 3 is in the position where the opening adjustment valve is closed.
There is no risk of incorrect operation. Furthermore, there is no need to perform any processing on the work implement lowering speed adjusting lever 3, and the structure is extremely simple.

In addition, when restarting the lifting and lowering of the work equipment, loosen the butterfly bolt 11 and slide the lever guide 9 to the right, so that the notch 14 separates from the work equipment lowering speed adjustment lever 3 and the long groove 13 aligns with the long hole 16.
The lever guide 9 is fixed by tightening the butterfly bolt 11 at the upwardly moved position, and the working machine lowering speed is lowered at a desired speed by reciprocating the working machine lowering speed adjusting lever 3 in the front and rear directions.

This idea involves inserting the work equipment lowering speed adjusting lever, which is provided on the body of the tractor so that it can freely rotate back and forth in one direction, into the guide groove of the lever guide, and allowing the work equipment lowering speed adjusting lever to rotate reciprocatingly through the guide groove. It is composed of a long groove along the moving direction and a notch cut out laterally in a part of the long groove, and the lever guide is arranged in a position where the notch engages with the work equipment lowering speed adjustment lever and a position where it separates. By being provided in the body so as to be movable and fixed at those positions,
By moving the lever guide and engaging the notch with the work equipment lowering speed adjustment lever, the work equipment lowering speed adjustment lever can be locked, and the work equipment lowering speed adjustment lever at the locked position can be locked. By setting the opening control valve in the hydraulic circuit that discharges oil from the hydraulic cylinder being raised and lowered to the closed position, the work equipment can be fixed in the raised position. The lever guide can be fixed simply by sliding the lever guide and the lever guide used as a guide for the work equipment lowering speed adjustment lever can also be used as a locking member, reducing the number of parts. This has the advantage that the structure of the locking device can be simplified.

[Brief explanation of the drawing]

The drawing shows one embodiment of this invention.
2 is a partially cutaway plan view, FIG. 3 is a rear view, and FIG. 4 is a plan view of the lever guide. 3... Work equipment lowering speed adjustment lever, 9... Lever guide, 13... Long groove, 14... Notch, 15
...Guide groove.

Claims (1)

[Scope of utility model registration request] A hydraulic device for raising and lowering a working machine connected to the body of the tractor is provided in the machine body, an opening adjustment valve is provided in a hydraulic circuit for discharging oil from a hydraulic cylinder of the hydraulic device, and the opening adjustment valve is provided in the machine body. A work equipment lowering speed adjustment lever for adjusting the opening degree of the valve is provided so as to be rotatable back and forth in one direction, and a long groove along the reciprocating rotation direction of the work equipment lowering speed adjustment lever and a part of this long groove are provided laterally. A lever guide having a guide groove formed with a notch is provided, and while the work equipment lowering speed adjusting lever is inserted into the guide groove, the lever guide is inserted so that the notch engages with the work equipment lowering speed adjusting lever. A lever lock device for adjusting the lowering speed of a working machine for a tractor, characterized in that the lever lock device is connected to the machine body so as to be movable between a position where the lever locks together with the lever and a position away from the lever, and fixed at these positions.