JPH0318985Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to an operating device for a hydraulic transmission, and can be used in tractors, combines, etc. equipped with a hydraulic transmission.

[Problems to be solved by conventional techniques and ideas]

Conventionally, the control rod is connected to an operating lever by an appropriate interlocking mechanism such as a link or rod, and is provided with a guide groove for inserting and guiding the operating lever. I pushed it down and went. Therefore, there was a problem in that the excessive operating force for this purpose excessively operated the control rod via the interlocking mechanism, damaging the interlocking mechanism, the control rod, and even the variable displacement pump.

Therefore, this idea was developed to control the amount of swinging so that even if an excessive operating force is applied to the operating lever, the operating lever cannot swing beyond the limit at which the operating rod of the variable displacement pump operates. The purpose is to improve the durability and operability of the machine and its operating mechanism.

[Means for solving problems]

This invention is based on a control rod 3 of a hydraulic transmission 2 that rotates back and forth from a neutral position to change the discharge amount and discharge direction of the variable displacement pump 1, and performs continuously variable speed forward and backward. A positioning tool 21 is provided for positioning the neutral position of gear shift 3, and an operating lever 5 for rotating the guide groove 19 provided in the control platform 18 from the neutral position A to the longitudinal direction B is interlocked via the interlocking mechanism 4. A lever is provided at the base of the operating lever 5 near the center of the operating swing so that it can be adjusted and fixed to move freely in the operating swing direction with respect to the operating lever 5 to regulate the operating limit of the control rod 3. The operating device for a hydraulic transmission is provided with a position regulating device 6.

[Effect of invention]

When the operating lever 5 is swung to the forward gear side,
The control rod 3 operates in the forward direction from the neutral position of the positioning tool 21 via the interlocking mechanism 4, and when the control rod 3 is swung toward the reverse gear shift side, the control rod 3 moves to the positioning tool 21.
The hydraulic transmission 2 is operated in the reverse direction from the neutral position side, and the discharge amount and discharge direction of the variable displacement pump 1 are changed according to the amount of rocking of the operating lever 5, so that the hydraulic transmission 2 is continuously variable. When the operating lever 5 is fully swung toward the maximum forward speed side, the swinging of the operating lever 5 is restricted by the position restrictor 6 provided near the oscillating center 7 position, so that the control rod 3 is moved in the forward operating direction. It will not operate above its operating limit.

[Effect of idea]

Therefore, since the amount of swing of the operating lever 5 is regulated, even if the operating lever 5 is tilted all the way in the forward operating direction for maximum forward speed operation and an excessive operating force is applied, the force will not be applied to the position regulating device. 6, there is no need to consider the excessive operating force of the operating lever 5 due to the strength of the interlocking mechanism 4, control rod 3, etc. in terms of design. The lever operation can be performed without any consideration, improving operability, and the operating limit of the control rod 3 in the forward operation direction can be limited to a safe range, so damage to the variable displacement pump 1 can be prevented. can.

In addition, the positioning of the shift neutral position of the control rod 3 is directly performed at the final position of the operation interlock with the positioning tool 21, and the regulation of the shift operation range by the manual operation lever 5 is performed at this shift neutral position. The operation is performed at a position close to the operation side by means of a position restrictor 6 which is movably and fixedly provided in the vicinity of the operation swing center 7 position of the operation lever 5 itself so that the front and rear operation rotation range is at the center. Because it is a thing,
This operating lever 5 is capable of performing a gear shift operation by accurately adjusting the operation while sensing the positioning of the neutral position and the operation restriction by the position regulating device 6, and the positioning of the shift neutral position by the positioning device 21, , the operating limit position is regulated by the position regulating device 6 at each different position, and is determined by the neutral positioning of the control rod 3 by the positioning device 21 and the neutral positioning of the operating lever 5 in the operation guide groove 19. Since the position limiter 6 of the operating lever 5 itself is moved and fixed relative to the operating lever 5 to adjust the operating limit position, setting and adjustment of these positions can be simplified and facilitated.

〔Example〕

The illustrated example shows a combine harvester, in which drive wheels 10 are provided on wheels 9 that protrude to both sides from a traveling gear box 8 provided at the front of the machine body, and a traveling device 11 is attached to the wheels 9.

Reference numeral 2 denotes a hydraulic transmission, which includes a variable displacement pump 1 which is transmitted and rotated in response to the rotation of an input shaft 13 transmitted by a belt from an output pulley 12 of a prime mover, and which is braked by hydraulic pressure discharged from this variable displacement pump 1. It consists of a hydraulic motor 14 that can freely rotate in forward and reverse directions, and the output shaft of this hydraulic motor 14 is connected to the input shaft in the traveling gear box 8.

3 is a control rod, and the swash plate angle of the variable displacement pump 1 is adjusted by swinging the control rod 3.
By arbitrarily adjusting the discharge direction and discharge amount of the discharged hydraulic oil, switching between forward and backward travel and continuously variable speed between forward and backward travel can be performed.

Reference numeral 5 denotes an operating lever, and a swinging member 17 that swings together with the operating lever 5 is loosely fitted and supported on a support shaft 16 fixed to a fixed member 15. It is configured to be able to freely swing back and forth with respect to the direction, and is fitted into a guide groove 19 provided in a pilot platform 18 on the side of the driver's seat. The swinging member 17 of the operating lever 5 and the control rod 3 are connected to a rod 2 which is one means of the interlocking mechanism 4.
0, and when the operating lever 5 is swung forward from the neutral position A in the direction of the arrow B, the control rod 3 is swung toward the forward side, and the combine is gradually accelerated forward from the stopped state, and conversely, the combine harvester is moved forward from the stopped state to the neutral position. When the control rod 3 swings backward from position A in the opposite direction of arrow B, the control rod 3 swings toward the reverse side, and the control rod 3 is interlocked to accelerate backward from the stopped state.

Reference numeral 21 denotes a positioning tool for the control rod 3, one end of which is pivotally connected to the mounting plate 22, and the other end attached to the traveling gear box 8 via a spring 23. The roller at the tip of the control rod 3 is attached to this positioning tool 21. The neutral position is regulated and maintained by sliding and fitting into the fitting part.

A swinging member 17 that swings together with the operating lever 5
A position regulating device 6 is provided at a position near the swing center 7. A long hole 24 is formed in this position regulating tool 6, and a locking protrusion 25 of the fixing member 15 is locked in the long hole 24. When the operating lever 5 is swung, the end of the long hole 24 is locked. The locking projection 25 contacts the locking protrusion 25 to restrict the amount of swing of the operating lever 5, thereby restricting the operation of the control rod 3 within limits. The position restrictor 6 is provided so that the position of the elongated hole 24 can be adjusted with respect to the swinging member 17, so that the amount of swinging of the operating lever 5 in the forward operating direction can be adjusted.

When the operating lever 5 is operated to the neutral position A, the roller at the tip of the control rod 3 is held at the neutral position of the positioning tool 21 via the rod 20. When the power is transmitted from the output pulley 12 of the prime mover to the input shaft 13, the power is transmitted to the hydraulic transmission 2. When the operating lever 5 is swung from the neutral position A in the direction of the arrow B, the forward speed of the combine is continuously variable according to the amount of this oscillation. The hole 24 is restricted by abutting against the locking projection 25 . At this time, the control rod 3 is at its operating limit in the forward direction, and if the control rod 3 is operated any further, it may overload the interlocking mechanism 4 and the variable displacement pump 1 of the hydraulic transmission 2, causing damage or malfunction. , even if the operating lever 5 is tilted with excessive operating force to operate at the highest speed on the forward side, the position regulating device 6 prevents the control lever 3 from moving.
The operating limits of the system can be regulated within a safe range. Also, by adjusting the position regulating tool 6,
The maximum forward speed limit can be adjusted depending on the conditions of the grain rod and the skill level of the operator. Next, when the operating lever 5 is swung from the neutral position A in the opposite direction of the arrow B, the reverse speed of the combine is continuously variable in accordance with the amount of oscillation.

[Brief explanation of the drawing]

The figure shows one embodiment of this invention.
The figure is a partial perspective view, and FIG. 2 is a front view thereof. In the figure, reference numeral 1 indicates a variable displacement pump, 2 indicates a hydraulic transmission, 3 indicates a control rod, 4 indicates an interlocking mechanism, 5 indicates an operating lever, 6 indicates a position restrictor, and 7 indicates a swing center.

Claims (1)

[Scope of utility model registration request] The control rod 3 of the hydraulic transmission 2 rotates back and forth from the neutral position to change the discharge amount and discharge direction of the variable displacement pump 1, and performs continuously variable speed forward and backward.
A positioning tool 21 is provided for positioning the neutral position of the control rod 3, and the interlocking mechanism 4 is also provided to control the operating lever 5, which rotates the guide groove 19 provided on the control platform 18 from the neutral position A to the longitudinal direction B. At the base of the operating lever 5 and near the center of the operating swing, there is provided a movable adjustment and fixing member at the base of the operating lever 5 in the operating swing direction with respect to the operating lever 5. An operating device for a hydraulic transmission, which is provided with a position regulating device 6 for regulating the position.