JPH0110970Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a lower link device of a three-point link coupling device for connecting a working machine to a moving vehicle such as a tractor, and the present invention is to facilitate the attachment and detachment of the working machine, especially the handling at the time of connection. With the goal.

A three-point link type coupling device is widely used as a form of coupling a working machine to the rear of a tractor body. However, in the conventional general three-point link type coupling device, the lower link is pivotally attached to both sides of the tractor body via a pivot shaft so as to be able to swing vertically, and the intermediate section is connected via a lift rod to lift the hydraulic system. Since the structure is simply connected to an arm, it is difficult to connect the work machine and the work tool.

In other words, since the conventional lower link cannot be bent or expanded, the connection part (ball joint part) at the rear end
If it does not match perfectly with the mounting pin on the work machine side,
Therefore, it is necessary to move one side of the tractor and work equipment to match the other, and no matter which one is moved, it is necessary to ensure that the two are perfectly aligned. It was very complicated and caused a big problem when connecting work machines.

Therefore, a device has been devised to make it easier to handle when connecting work equipment by dividing the main body into a lower linkable body and a movable part and connecting the two in a flexible and bendable manner (for example, 48-96115, U.S. Pat.

The above-mentioned Utility Model Application Publication No. 48-96115 and Utility Model Application No. 55-
The lower link device described in Publication No. 68404 is provided with a cylindrical part at the rear end of the lower link main body which is pivotally supported on the tractor body, and a movable link can be freely inserted into and removed from the cylindrical part in the longitudinal direction of the lower link. is embedded in
A connecting part for connecting a work machine is provided at the rear end of the movable link, a notch is formed in the cylindrical part, a pair of support parts are provided in front and behind the notch, and the movable link is latched to the support part. The locking tool is rotatably supported around the front-rear axis, and the locking tool has a lock part that can move forward and backward into the notch, and an operating part for rotating the lock part around the front-rear axis. Further, an elastic member is provided that urges the locking tool in one direction of rotation, and an engaging portion is provided that engages the lock portion with the movable link to prevent movement in the longitudinal direction. It was warm.

In the conventional type, the movable link is removably fitted into the cylindrical part, so when connecting the tractor and the work equipment, the tractor must be moved backward after the movable link is connected to the work equipment. In this case, the movable link must be inserted into the cylindrical portion, and two people are required: one to drive the tractor and the other to insert the movable link into the cylindrical portion. The insertion work was extremely dangerous.

On the other hand, in the device described in the above-mentioned Japanese Utility Model Application Publication No. 54-177305, the movable link is provided with a retaining portion, and the movable link is telescopically fitted into a cylindrical portion. The locking portion and the engaging portion are configured to engage with each other by connecting the working machine in a state in which the movable link is moved and then retracting the tractor to reduce the size of the movable link.

Therefore, with this conventional type, one person can perform the connection work, but since the operating part for operating the lock part protrudes outward, the operating part may be operated by an unexpected external force, causing damage to the lock part. There was a risk that the engagement portion would be disengaged. Further, since the retaining portion is a flange that protrudes from the outer diameter of the movable link, it is difficult to assemble it into the cylindrical portion.

Furthermore, in the conventional device, the cylindrical portion and the movable link are fitted in a substantially tight fit, and there is no lateral wobbling, making it difficult to connect to a working machine.

Therefore, the present invention makes it easy to assemble the movable link and the cylindrical part, prevents the lock part from being accidentally disengaged from the engagement part, and allows the movable link to swing in the left-right direction. An object of the present invention is to provide a lower link device that facilitates connection work with a working machine.

Therefore, the feature of the present invention is that a cylindrical part 11 is provided at the rear end of the lower link main body 10 which is pivotally supported on the tractor body 1, and a movable link 12 is attached to the cylindrical part 11. A connecting portion 35 for connecting a working machine is provided at the rear end of the movable link 12, and a notch 19 is formed in the cylindrical portion 11. A pair of support parts 21 are provided on the support part 21, and a locking tool 2 is attached to the support part 21.
2 is rotatably supported around the front and rear axis, and the locking tool 22 has a lock portion 22 that can freely move forward and backward into the notch 19.
b, and an operating portion 22c for rotating the lock portion 22b around the longitudinal axis, and further provided with an elastic member 25 for biasing the locking tool 22 in one direction of rotation. , and in a lower link device in which the movable link 12 is provided with an engagement portion with which the lock portion 22b engages, the engagement portion is spaced apart in the longitudinal direction of the lower link and located on the front side of the movable link 12. It consists of a first engaging part 32 provided on the rear side and a second engaging part 33 provided on the rear side, and when the lock part 22b is engaged, the first engaging part 32 a front end surface 36 that abuts against and prevents movement of the movable link 12 in the extension direction;
Then, in order to allow movement of the movable link 12 in the contraction direction, it slides into contact with the lock portion 22b and the lock portion 22b
an inclined surface 3 for rotating the elastic member 25 against the elastic member 25;
8, the second engaging portion 33 is sized to engage with the lock portion 22b and prevent the movable link 12 from expanding and contracting, and the front end of the movable link 12 has the lock portion 22b. and the first engaging portion 32 are engaged,
An inclined surface 42 that allows the movable link 12 to swing in the left-right direction is formed, and the pair of support portions 21
This is because the size is large enough to cover the operating portion 22c from the front and back directions.

The invention will now be described in detail with reference to the illustrated embodiments.

In FIG. 1, 1 is a tractor body, 2 is a rear wheel, and 3 is a driver's seat. Reference numeral 4 denotes a hydraulic system mounted on the rear part of the tractor body 1, which has a pair of left and right lift arms 5. Reference numeral 6 denotes a rotary device as a working machine, which is attached to the rear of the tractor body 1 via a three-point link 7 and can be raised and lowered by a hydraulic device 4.

The three-point link 7 includes one top link 8 and a pair of left and right lower links 9. Each lower link 9 includes a lower link body 10 and a lower link body 1.
0 has a movable link 12 inserted into a cylindrical portion 11 at the rear end so as to be expandable and retractable in the longitudinal direction. and is connected to the lift arm 5. Of course, the check chain is also connected to the lower link body 10.

As shown in FIGS. 2 to 5, the cylindrical portion 11 is formed by combining a pair of left and right side plates 15 and a pair of upper and lower plates 16 and 17 connecting the side plates 15 into a short cylindrical shape. A square notch 19 is formed from the upper edge near the rear end of one side plate 15, and a pair of corner members 20 are welded on the side plate 15 before and after this notch 19. Front and rear support portions 21 are formed.

Reference numeral 22 denotes a locking tool inserted between a pair of corner members 20, in which a locking portion 22b and an operating portion 22c protrude in the diametrical direction around a circular fitting portion 22a. is rotatably supported by a support shaft 23 supported by the corner member 20. The locking tool 22 is rotated by pushing the operating portion 22c with a finger, and the locking portion 22b can be moved forward and backward with respect to the notch 19.

The support shaft 23 is formed of a pair of cylindrical members 24 that are arranged opposite to each other along the same axis, and a coil spring 25 with a front and back reverse spiral is installed inside both cylindrical members 24, and both ends of the spring 25 are It is hooked to each cylindrical member 24. Each cylindrical member 24 has a parallel surface 26 formed on the outer periphery of one end, and can be rotated by this parallel surface 26 using a spanner or the like. Rotation is prevented.

Reference numeral 28 denotes a pin driven into the fitting portion 22a, which engages the center of the coil spring 25, and the locking tool 22 is urged in the direction of FIG. 5a by the coil spring 25.

The movable link 12 has an inclined part 31 formed by cutting out a lower corner part of the front end, and has a longitudinally long notch-shaped first engagement part 32 on the front upper edge thereof, and a notch-shaped second engagement part 32 on the central upper edge thereof. It has an engaging portion 33, and a connecting portion 35 having a ball joint structure that is detachable from the mounting pin 34 of the rotary device 6 at its rear end.

The first engaging portion 32 has a width that is approximately half the thickness of the movable link 12, and is formed with a front end surface 36, a parallel surface 37, and an inclined surface 38, and a recess 39 in the remaining approximately half width portion. It is formed. Note that the recess 40 is a cutting tool introduction part for forming the front end surface 36 and the parallel surface 37.

This first engaging portion 32 can engage with the locking portion 22b of the locking tool 22 when the movable link 12 is extended, and when engaged, the movable link 12
When it comes into contact with the lock portion 22b, the movement in the extension direction is prevented, and it is free to move relative to the lock portion 22b by the length of the parallel surface 37 and the inclined surface 38. The opposite contraction operation is allowed by the pushing out of the locking part 22b as the inclined surface 38 comes into contact with the locking part 22b. Further, by providing the inclined portion 31 and the recessed portion 39, the movable link 12 can swing upward to the state shown by the imaginary line in FIG.
Vertical alignment is possible.

Furthermore, by providing the inclined surface 42 at the front end of the movable link 12, the movable link 12 can be swung in the left-right direction, making it easier to connect the movable link 12 to a working machine.

The second engaging portion 33 is formed in a rectangular shape over the entire width of the movable link 12, and has approximately the same longitudinal length as the lock portion 22b, and is capable of engaging with the lock portion 22b when the movable link 12 contracts. By matching, the movable link 12 is prevented from extending or contracting and is locked in the retracted position.

When the lock portion 22b engages with the second engaging portion 33, as shown in FIGS. 3 and 4, the operating portion 2
2c fits between the front and rear support portions 21 and is protected from inadvertent rotation due to contact with objects. That is, the length of the operating portion 22c is formed to be approximately the same as the length from the upper end of the corner member 20 to the cylindrical member 24.

Next, the action will be explained.

When connecting the rotary device 6 to the three-point link 7,
Push the operating part 22c of the locking tool 22 with your finger and rotate it in the direction of FIG. to release the lock.

In this state, the movable link 12 is extended, the pressure on the operating portion 22c is released, and the locking portion 22b is engaged with the first engaging portion 32 by the action of the coil spring 25.

Thereafter, the tractor body 1 is moved backward to approach the rotary device 6, and the connecting portion 3 of the movable link 12 is moved backward.
5 is arranged opposite to the mounting pin 34. Lock part 22
Since b engages with the first engaging portion 32, the connecting portion 35 can be freely adjusted in position forward and backward and up and down, and fits into the mounting pin 34 while adjusting its position.

After the movable link 12 is connected to the rotary device 6, when the tractor body 1 is further moved backward, the movable link 12 is contracted into the cylindrical part 11, and the lock part 22
b is detached from the first engaging part 32 while sliding on the inclined surface 38, and when the second engaging part 33 moves to a position facing the lock part 22b, the coil spring 2
5, the second engaging portion 33 is automatically engaged. Now the movable link 12 is the lower link body 1
The rotary device 6 is locked at 0, and the rotary device 6 can be pulled and moved up and down together.

FIG. 6 shows a second embodiment of the present invention, in which the movable link 12 has an inclined surface 42 formed at its front end, while an inclined surface 43 is formed at the rear end of the lock portion 22b of the locking tool 22. It is formed.

In the embodiment, the movable link 12 is connected to the cylindrical portion 11.
However, in this second embodiment, as the movable link 12 is inserted into the cylindrical portion 11, the slanted surface 42 Since the lock portion 22b can be pushed in the release direction b by contacting the inclined surface 43, the operation of the locking tool 22 when inserting the movable link 12 is completely unnecessary.

Note that the locking portion 22b may be formed of a round bar having an axis perpendicular to the fitting portion 22a, thereby eliminating the need for machining the inclined surface 43.

According to the present invention described in detail above, the movable link can be inserted and removed from the cylindrical part by retracting the lock part from the notch. Assembly with the cylindrical part becomes easy.

Further, first and second engaging portions are provided to prevent the movable link from coming off and to prevent movement in the longitudinal direction, and
Since the movable link is swingable in left and right directions,
Connection work becomes easier.

Further, since the operating portion is covered by the support portion, no unexpected external force is applied to the operating portion, thereby preventing accidental disengagement between the locking portion and the engaging portion.

[Brief explanation of the drawing]

1 to 5 show an embodiment of the present invention, in which FIG. 1 is a usage state diagram, FIG. 2 is an exploded perspective view,
Fig. 3 is a sectional side view, Fig. 4 is a plan view, Fig. 5 is a sectional view taken along the - line in Fig. 3, and Fig. 6 is a second cross-sectional view of the present invention.
FIG. 2 is an explanatory diagram showing main parts of the embodiment. 9...Lower link, 10...Lower link body,
11... Cylindrical part, 12... Movable link, 19...
Notch portion, 21... Front and rear support portion, 22... Locking tool,
22a...Fitting part, 22b...Lock part, 22c
...Operation section, 32...First engaging section, 33...Second
Engagement part, 35...connection part.

Claims (1)

[Claims for Utility Model Registration] Lower link body 1 pivotally supported on tractor body 1
A cylindrical portion 11 is provided at the rear end of the cylindrical portion 1.
1, a movable link 12 is fitted inside the lower link so as to be expandable and contractible in the longitudinal direction, a connecting portion 35 for connecting a working machine is provided at the rear end of the movable link 12, and a notch 19 is provided in the cylindrical portion 11. A pair of support parts 21 are provided before and after the cutout part 19, and the support parts 2
1, a locking tool 22 is rotatably supported around the front-rear axis. It has an operating portion 22c for operation, and is further provided with an elastic member 25 that urges the locking tool 22 in one direction of rotation, and the locking portion 22b engages with the movable link 12. In the lower link device, the engaging portion is provided on the front side of the movable link 12 and the first engaging portion 32 provided on the front side of the movable link 12 and spaced apart in the longitudinal direction of the lower link. and a second engaging part 33 which is attached to the lock part 32, and the first engaging part 32 has a front end that comes into contact with the lock part 22b and prevents the movable link 12 from moving in the extension direction when the lock part 22b is engaged. Face 36
Then, in order to allow movement of the movable link 12 in the contraction direction, it slides into contact with the lock portion 22b and the lock portion 22b
The inclined surface 2 rotates against the elastic member 25.
8, the second engaging portion 33 is sized to engage with the lock portion 22b and prevent the movable link 12 from expanding and contracting, and the front end of the movable link 12 has the lock portion 22b. and the first engaging portion 32 are engaged,
An inclined surface 42 that allows the movable link 12 to swing in the left-right direction is formed, and the pair of support portions 21
A lower link device characterized in that it is sized to cover the operating portion 22c from the front and rear directions.