JPH0735526Y2 - Working machine coupling device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a coupling device for a working machine that is coupled to a rear portion of a tractor via a three-point link mechanism.

2. Description of the Related Art Conventionally, a three-point link mechanism has been widely adopted for connecting a working machine to the rear part of a tractor, and further, a working machine connecting device connected through the three-point link mechanism is Various types of simple attachment / detachment mechanisms are widely used for the purpose of facilitating attachment / detachment.

As an example of the simple attachment / detachment mechanism, a connecting body attached to the rear part of the three-point link mechanism, an engagement recess formed by opening upward at the center of the upper part of the connecting body, and a rearward opening at both lower sides of the connecting body There is a pair of left and right engaging recesses formed by the above, and an engaging shaft portion that is provided in the working machine and engages and disengages with the engaging recess portion. A pair of hooks is provided on the left and right to prevent the hooks from being disengaged from the pair of engaging recesses. These hooks wait in a state where the engaging shaft portion is engaged with the engaging recessed portion and prevent the engaging shaft portion from coming off the engaging recessed portion, and the engaging shaft portion It is rotatably provided in a second rotation position that allows it to be disengaged from the engagement recess.

Problem to be Solved by the Invention The hook is fixed in position between the first rotation position and the second rotation position by the action of the fixing spring. Therefore, when removing the work implement connected to the tractor and then connecting another work implement, after rotating the hook to the second rotation position and fixing the position by the action of the fixing spring, The work machine must be removed, and after the work machine is removed, the hook must be rotated to the first rotation position and fixed in position by the action of the fixing spring, so that the work machine must be connected. For this reason, it is necessary to operate the left and right hooks four times by combining each two times, which is troublesome.

Means for Solving the Problems A pair of left and right engaging recesses are engaged between a rear part of a three-point link mechanism attached to a rear part of a tractor and a front part of a working machine, and the engaging recesses are detachably engaged with each other. An engaging portion having a pair of right and left engaging shaft portions is provided, the engaging shaft portion is allowed to engage with the engaging recess portion, and the engaging shaft portion engaged with the engaging recess portion is A pair of rotatable hooks is provided on the left and right at a first rotation position that prevents the engagement shaft portion from being disengaged and a second rotation position that allows the engagement shaft portion to be disengaged from the engagement recess. A coupling device for a working machine, comprising a spring for selectively urging the hook toward a first rotation position and a second rotation position according to a rotation angle of the hook, wherein the engagement shaft Urging body for urging the hook toward the first rotation position in response to the disengagement of the hook from the engaging recess. And the biasing force of the biasing body is set stronger than the biasing force of the spring, and the left and right hooks are coupled by a coupling member that acts in a direction to rotate the hook toward the second rotation position. did.

In the state in which the working machine is connected, the hook is rotated to the first rotation position and is fixed at the first rotation position by the urging force of the spring, and the engagement shaft portion is removed from the engagement recess. Prevent you from leaving. When removing the implement,
When one of the left and right hooks is rotated from the first rotation position to the second rotation position, the other hook connected by the connecting member is also changed from the first rotation position to the second rotation position at the same time. Turn to. When the hook is rotated to the second rotation position, the direction of the biasing force of the spring acting on the hook is reversed, and the hook is fixed at the second rotation position by the biasing force of the spring, and the engaging shaft portion is It is possible to disengage from the engaging recess. Further, when the engagement shaft portion is disengaged from the engagement recessed portion, the hook is rotated toward the first rotation position by the urging force of the urging body which acts in response to the disengagement. The hook rotated to the first rotation position is fixed at the first rotation position by the biasing force of the spring, and the engagement shaft portion is allowed to engage with the engagement recess.

Embodiment An embodiment of the present invention will be described with reference to the drawings. First, a three-point link mechanism 4 consisting of a pair of left and right lower links 2 and a top link 3 located at the center is attached to the rear part of the tractor 1, and a mountain-shaped connection is provided at the rear part of the three-point link mechanism 4. The frame 5 is connected. Connection frame 5
A pair of left and right support plates 6 are fixed close to each other at the center of the upper part of the, and these support plates 6 are formed with engaging recesses 7 that are open upward. Further, a pair of left and right engaging recesses 8 that are open rearward and a pair of left and right connecting pins 9 to which the rear ends of the lower links 2 are connected are formed in the lower portion of the connecting frame 5. Next, a rotary working machine 10, which is a working machine, is provided, and the rotary working machine 10 has an engaging shaft portion 11 that is engageably and disengageably engaged with the engaging concave portion 7.
And a pair of left and right engaging shaft portions 12 that are removably engaged with the engaging recesses 8. Then, the rotary working machine is constituted by these engaging concave portions 7 and 8 and the engaging shaft portions 11 and 12.
An engagement portion 13 for connecting the 10 to the rear portion of the three-point link mechanism 4 is formed.

A pair of left and right support shafts 14 having horizontal and horizontal axis centers are rotatably provided around the center axis in the lower part of the connecting frame 5, and one end of each of the support axes 14 is shown in FIGS. A rotatable hook 15 is fixed between a first rotation position shown in the figure and a second rotation position shown in FIG.
A lever 16 is fixed to the other end of the. Further, a spring 17 is attached to the lever 16 to selectively bias the hook 15 toward the first rotation position and the second rotation position according to the rotation position of the hook 15. .

A torsion coil spring 18 as an urging body is attached to the support shaft 14.
Is attached, and one end of the torsion coil spring 18 is in contact with the outer peripheral surface of the connecting pin 9. Further, the torsion coil spring 18 has a shaft abutting portion 19 elastically abutting on a lower outer peripheral surface of the engaging shaft portion 12 engaged with the engaging concave portion 8 and extending below the hook 15. As shown in FIG. 8, when the engaging shaft portion 12 is released from the engaging concave portion 8, the engaging shaft portion 12 elastically abuts on the lower end edge of the hook 15 located at the second rotation position, and this hook 15 A hook contact portion 20 for urging 15 toward the first rotation position is formed. Further, one end of a wire 21 as a connecting member is connected to the tip ends of the pair of left and right levers 16, and the wire 21 is arranged along the connecting frame 5.

In such a structure, first, the connection of the rotary working machine 10 to the rear part of the tractor 1 will be described. Tractor 1
Towards the rotary working machine 10 placed behind the tractor 1
Is moved backward to engage the engagement concave portion 7 with the engagement shaft portion 11. Then, when the lift arm 22 connected to the lower link 2 is driven to raise the three-point link mechanism 4 rearward and upward, the rotary working machine 10 is lifted, and when the lower end of the rotary working machine 10 separates from the ground, the rotary working machine 10 is lifted. The lower part of 10 rotates forward with the engaging recess 7 as a fulcrum. And the fourth
As shown in the figure, the left and right engaging shaft portions 12 face the engaging recessed portion 8, and at this time, the biasing force of the spring 17 causes the hook 15 to pivot.
The hook 15 acts in a direction of rotating in the direction of arrow A around the axis of 14, and the hook 15 is fixed at a first rotation position that allows the engagement shaft portion 12 to engage with the engagement recess 8. Has been done.

When the lower part of the rotary working machine 10 continues to rotate forward,
As shown in FIG. 5, the engaging shaft portion 12 pushes down the hook 15 and abuts on the shaft abutting portion 19 to twist the coil spring.
18 is pushed down to enter the engaging recess 8. When the engaging shaft portion 12 enters the innermost portion in the engaging recessed portion 8, the hook 15 automatically returns to the first rotational position by the urging force of the spring 17, as shown in FIG. The shaft portion 12 is prevented from being disengaged from the engagement concave portion 8 and the connection of the rotary working machine 10 is completed. The torsion coil spring 18 is pushed down by the weight of the rotary working machine 10 acting on the engagement shaft portion 12, and the hook contact portion 20 is maintained in a state of not contacting the lower end edge of the hook 15.

Next, a case where the rotary working machine 10 is removed from the rear part of the tractor 1 will be described. After lowering the three-point link mechanism 4 to ground the lower part of the rotary working machine 10, the wire 21 is pulled upward by grasping the substantially middle portion of the wire 21. Wire
By pulling 21 upward, the left and right levers 16 and the hook 15 rotate around the axis of the support shaft 14 in the arrow B direction, and when the hook 15 rotates in the arrow B direction to a predetermined position, the biasing force of the spring 17 is exerted. Acts in a direction to rotate the hook 15 in the direction of arrow B, the hook 15 is fixed at the second rotation position shown in FIG. 7, and the engagement shaft portion 12 is allowed to disengage from the engagement recess 8. Ready to go.

Then, when the tractor 1 is advanced, the engagement shaft portion 12 moves rearward in the engagement recess 8 as shown in FIG.
The torsion coil spring 18 gradually rises with the backward movement of the. When the torsion coil spring 18 rises and the hook contact portion 20 abuts on the lower end edge of the hook 15, the biasing force of the torsion coil spring 18 stronger than the biasing force of the spring 17 causes the hook 15 to move around the spindle 14 in the direction of arrow A. When the hook 15 is rotated in the direction of arrow A to a predetermined position in the direction of arrow A, the biasing force of the spring 17 also acts to rotate the hook 15 in the direction of arrow A. Then, when the engagement shaft portion 12 is completely disengaged from the engagement recessed portion 8, the hook 15 moves to the fourth position.
The position is fixed by turning to the first turning position shown in the figure. Then, the engagement shaft 11 is removed from the engagement recess 7 to complete the removal of the rotary working machine 10.

In the present embodiment, the wire 21 is used as the connecting member, and the middle portion of the wire 21 is pulled so that the left and right hooks
Although 15 is simultaneously rotated from the first rotation position to the second rotation position, a rotation shaft having a horizontal axis as a connecting member and pivotally supported by the connecting frame 5 is used. , The arm fixed to both ends of the rotating shaft and the lever
By connecting with 16, it is possible to rotate the rotary shaft and simultaneously rotate the left and right hooks.

Advantageous Effects of Invention The present invention, when the hook is rotated to the second rotation position to disengage the engagement shaft portion from the engagement recess as described above,
The hook located at the second rotation position is automatically rotated to the first rotation position by the biasing force of the biasing body to allow the engagement shaft portion to engage with the engagement recess. Therefore, when the work implement connected to the tractor is removed and the work implement is connected again, the hook is operated once from the first rotation position to the second rotation position. Moreover, a pair of left and right hooks are connected by a connecting member, and the left and right hooks can be simultaneously rotated from the first rotating position to the second rotating position via the connecting member.
This has an effect that the work machine can be easily attached to and detached from the tractor without any trouble.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a side view of the whole, FIG. 2 is a side view showing the entire structure of a connecting portion of a working machine, and FIG. The front view shown in FIGS. 4 to 8 is a side view for explaining the attaching and detaching process of the working machine. 1 ... tractor, 4 ... three-point link mechanism, 8 ... engaging recess, 10 ... working machine, 12 ... engaging shaft, 13 ... engaging part, 15
…… Hook, 17 …… Spring, 18 …… Burder, 21 ……
Connecting member

Claims (1)

[Scope of utility model registration request] 1. A pair of left and right engaging recesses between a rear part of a three-point link mechanism attached to a rear part of a tractor and a front part of a working machine, and left and right engageable and disengageable with these engaging recesses. An engaging portion having a pair of engaging shaft portions is provided, and the engaging shaft portion is allowed to engage with the engaging concave portion, and the engaging shaft portion engaged with the engaging concave portion is disengaged. And a pair of rotatable hooks are provided on the left and right at a first rotation position that prevents the above-mentioned engagement and a second rotation position that allows the engagement shaft portion to be disengaged from the engagement recess. In the coupling device of the working machine, which is provided with a spring for selectively urging the hook toward the first rotation position and the second rotation position according to the rotation angle of the engaging shaft portion, A biasing body that biases the hook toward the first rotation position in response to the disengagement from the engagement recess is provided. In addition, the urging force of the urging member is set to be stronger than the urging force of the spring, and the left and right hooks are connected by a connecting member that acts in a direction to rotate the hook toward the second rotation position. A coupling device for work machines.