JPS6129211Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention connects a ground work device to the aircraft body using a fluid pressure lift operation mechanism so that it can be raised and lowered, and changes the descending speed of the ground work device using the fluid pressure circuit of the lift operation mechanism. A ground work machine, which is equipped with a variable throttle valve for interposing a variable throttle valve, and has an interlocking mechanism that links movement of a lift arm of the lifting operation mechanism that is displaced as the ground work device lowers and operation of the variable throttle valve. Regarding.

This type of ground working machine equipped with a ground working device such as a rotary tiller is designed to rapidly lower the tilling device from the ascent limit to near the ground surface, and then slowly descend from near the ground surface to the descending limit. , there is a need to improve work efficiency and prevent dangers caused by the tiller reaching the ground surface. Conventionally, the lowering position detection device of the tiller and the detection result are used to detect when the tiller reaches the ground surface. , and is equipped with an electric controller that repeatedly switches the control valve of the lifting operation mechanism between the lowering position and the stop position of the tiller as it descends, and the control configuration itself is structurally complex. This has the disadvantage that the entire working machine is expensive and prone to control troubles as it is prone to breakdowns.

In addition, Japanese Utility Model Application No. 55-18915 discloses an interlocking mechanism that links the movement of a lift arm and the operation of a throttle valve. A cam that is linked to the rotational movement of the arm is operated via a rod in the middle, and the contact position of this lever mechanism and the cam is made adjustable so that the oil passage is constricted and A mechanical device is disclosed that is configured to change and adjust the height of the work device.

This configuration has a problem in that it requires complex and expensive components such as a cam attached to the lift arm and a lever mechanism in contact with the cam.

The technical problem to be solved by this invention is to effectively utilize a bracket equipped with an interlocking mechanism for returning the operating lever between the operating lever of the control valve and the lift arm, which are provided as part of the fluid pressure lifting mechanism. By doing so, it is an object of the present invention to provide an interlocking mechanism between a throttle valve and a lift arm that has a simple structure and is difficult to break down.

The technical means provided to solve the above technical problem is that the hydraulic lifting operation mechanism has one end that is pivoted to an operating lever of a control valve, and the other end that is mounted on a first bracket attached to the lift arm. After the lift arm, which is provided with a first rod slidably inserted through the rotating member and moves in accordance with the raising or lowering operation of the operating lever, reaches the raising limit or lowering limit of the ground work device, The interlocking mechanism is constructed such that the operation lever is returned to the neutral position via the first rod, and the interlocking mechanism includes a second rod whose one end side is connected to a second rotating member provided in the bracket. A long hole is formed on the other end side, and an operating member, which is swing-biased to a non-throttling operation position by a spring of the throttle valve, is slidably engaged in the long hole, and the throttle valve is When the ground work equipment is located within a specific lifting range from near the ground surface to the lowering limit, it is in a throttled state, and when the ground work equipment is located within a lifting range outside of the specific lifting range, it is in a non-throttled state. It is a mechanical interlocking mechanism that operates automatically.

The above technical means works as follows. When the operating lever is operated to the up or down side, the control valve is switched to the up or down side and the first rod is slidably moved. By switching the control valve, the lift arm moves upward or downward, and after reaching its upward limit or downward limit, the operating lever is returned to the neutral position via the first rod. As the lift arm moves, the mechanical interlocking mechanism operates, and the second rod attached to the bracket controls the throttle valve via the elongated hole and spring so that the ground work device is within a specific lifting range from near the ground surface to the lowering limit. When the ground working device is located within the lifting range outside the specific lifting range, it is automatically operated to be in the locked state.

Therefore, the present invention has the following effects. This makes it possible to automatically return the insertion lever to neutral after reaching the ascent limit or descending limit of the ground implement, and to automatically adjust the descending speed of the ground implement at the same time, resulting in an easy-to-operate ground implement. I ended up getting it.

Moreover, the above was achieved by using a single bracket and adding an extremely simple structure such as a rod, a long hole, and an operating member with a spring.

Next, embodiments of the present invention will be described based on the drawings.

As shown in FIG. 1, a rotary tiller 1 is connected to the rear body of a riding tractor so that it can be raised and lowered, and the rotary tiller 1 is configured to transmit rotational power from the tractor to the tiller 1. It is configured.

In configuring the elevating and lowering operation mechanism of the tilling device 1,
As shown in FIGS. 1 to 3, a lift arm 3 is attached to the transmission case 2 of the tractor so that it can swing vertically around an axis P by a hydraulic cylinder 4, and a connecting shaft 5 is attached to the transmission case 2.
The machine frame and the lift arm 3, which are connected to each other so as to be vertically swingable, are pivotally connected by a rod 6, and as shown in FIG. 4, a control valve 19 is installed in the hydraulic circuit for the cylinder 4, and The operating lever 7 for this is shown in Figures 2 and 3.
As shown in the figure, attached to the mission case 2,
When the lever 7 is operated from the neutral position N to the operating position DN where it is swung toward the front of the vehicle body, the lift arm 3 is lowered, the tilling device 1 is swung downward, and the lever 7 is swung from the neutral position N toward the rear of the vehicle body. When the tiller is operated to the UP operating position, the lift arm 3 is raised and the tilling device 1 is swung upward. Also, the second
As shown in FIGS. 3 and 3, one end of a first push-pull rod 8 is pivotally connected to the lever 7, and the other end of the first push-pull rod 8 is attached to a bracket 9 attached to the lift arm 3. The first contact member 11 is slidably inserted into the rotating member 10 and comes into contact with the rotating member 10 as the tilling device 1 reaches the lowering limit L, and as the tilling device 1 reaches the upper limit H. The second contact members 12 that contact the rotating member 10 are respectively attached to the rods 8 so that their positions can be changed. The operating lever 7 is pushed or pulled.
is configured so that it is automatically returned to the neutral position N, and is also configured so that the ascending limit H or descending limit L of the tilling device 1 can be changed by changing the mounting position of each of the abutment members 11 and 12. be.

As shown in FIG. 4, a variable throttle valve 13 for changing the descending speed of the tilling device 1 is installed in the hydraulic circuit of the cylinder 4, and as shown in FIGS.
As shown in the figure, a long hole 16 is formed in the other end of the second push-pull rod 15, whose one end is connected to the second rotating member 14 provided in the bracket 9, and in the long hole 16, The operating member 18 of the throttle valve 13, which is biased to the non-throttling operation position by the spring 17, is slidably engaged to move the throttle valve 13 to the lowering limit L of the tiller 1 from the vicinity G above the ground surface. When located within the specified lifting range A up to
It is in a constricted state due to the contact between the rod 15 and the operating member 18, and when the cultivating device 1 is located within the lifting range B outside the specific lifting range A, it is stopped by the action of the elongated hole 16 and the action of the spring 17. It is linked to the lift arm 3 so that it is automatically operated in conjunction with the raising and lowering of the tiller so that it is in the throttle state. In other words,
Before starting work, move lever 7 to lower position PN.
By simply operating the tiller 1, the tiller 1, which has been raised above the ground, will rapidly descend until it reaches a point G near the ground surface, and when it reaches a point G near the ground surface, the descending speed will be automatically reduced and it will return to the working position. descends at a slower speed to near G above the ground surface, and the tiller 1 is lowered.
It is constructed so that it can be lowered and set to the working position as quickly as possible while preventing troubles caused by it rapidly sinking into the ground.

The second push/pull rod 15 may be of any type as long as it can transmit the operating force of the operating wire 3 to the throttle valve 13 as the operating force, and these are collectively referred to as the mechanical interlocking mechanism 15.

Furthermore, the lifting operation mechanism may have an operation configuration that employs various fluids such as air other than oil as a pressure medium;
It is possible to change the operation configuration to one in which the tilling device 1 is slid up and down.

Further, the tilling device 1 can be changed to a trencher or the like, and these are collectively referred to as the ground working device 1.

[Brief explanation of the drawing]

The drawings show an embodiment of the ground work machine according to the present invention, and FIG. 1 is a side view of the rear part of the riding tiller, FIG. The figure is a hydraulic circuit diagram. 1... Working device, 3... Lift arm, 7...
Operation lever, 8...first rod, 9...bracket, 10...first rotating member, 13...variable throttle valve, 14...second rotating member, 15...second rod, 16...elongated hole , 17... Spring, A...
Specific lift range, B...lift range, H...lift limit, L...fall limit, G...above the ground surface.

Claims (1)

[Scope of utility model registration request] The ground work device 1 is connected to the aircraft body by a hydraulic lifting operation mechanism so as to be able to rise and fall freely, and a variable throttle valve 13 for changing the descending speed of the ground work device 1 is connected to the fluid pressure circuit of the lifting operation mechanism. The ground work machine is equipped with an interlocking mechanism that links the movement of the lift arm 3 that is displaced as the ground work device 1 of the lifting operation mechanism lowers and the operation of the variable throttle valve 13. The lifting operation mechanism includes a first rod 8 whose one end is pivotally supported by the operating lever 7 of the control valve 19 and whose other end is slidably inserted into a first rotating member 10 provided on a bracket 9 attached to the lift arm 3. After the lift arm 3, which moves as the operating lever 7 is raised or lowered, reaches the upper limit H or the lower limit L of the ground work device 1, the first rod 8 Operation lever 8
The interlocking mechanism includes a second rod 15 connected at one end to a second rotating member 14 provided in the bracket 9, and a long hole at the other end. 16, and the operating member 18 of the throttle valve 13, which is swing-biased to the non-throttle operation position by the spring 17 of the throttle valve 13, is slidably engaged in the elongated hole 16.
3, when the ground work device 1 is located within a specific lifting range A from the vicinity G above the ground surface to the lowering limit L, it is in the throttle state; A ground work machine characterized by having a mechanical interlocking mechanism that is automatically operated so that it is in a non-throttle state when located within B.