JP2537684B2 - Work implement attachment / detachment device for tractors - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention connects a hitch frame to a rear portion of a machine body via a link so that the hitch frame can be moved up and down, and the work machine is attached to and detached from the hitch frame at an upper portion and a lower portion. To a work implement attachment / detachment device for the tractor.

(B) Prior Art Conventionally, a work machine attaching / detaching device for a tractor having a connecting pin, a movable locking member, and a lock member that face each other in the lower portion of the hitch frame and the front portion of the lower portion of the working machine has already been provided. Are known.

(C) Problems to be Solved by the Invention The work implement attaching / detaching device in the known tractor is troublesome because the left and right locking means are manually released or locked by the operator when the operator gets down to the ground. It was

(D) Means for Solving the Problems In the present invention, a hitch frame 5 is movably connected to a rear portion of a machine body via a link, and a work machine is attached to and detached from the hitch frame 5 at an upper portion and a lower portion. In the tractor, the lower connecting portion of the hitch frame 5 can be rotated to a connecting plate 8 having a groove 8a into which the connecting pin 17 of the working machine enters and a portion vertically separated from the groove 8a of the connecting plate 8. And a locking plate 10 having an opening groove 10c intersecting with the groove 8a for allowing the connecting pin 17 to move in and out, and a pivoting point 10a provided on the connecting plate 8 so as to be rotatable. Then, the locking plate 10 and the operation lever 25 integrally provided with the cam 11 pivotally attached to the support shaft 11a provided on the connecting plate 8 are provided opposite to one side of the connecting plate 8 and the ammunition is provided. 26, and the locking plate 10 is urged to rotate in the direction in which the connecting pin 17 comes out and the cam 11
An engaging and disengaging first stopper 10b is provided to prevent the connecting pin 17 that abuts against and engages with the
An elastic body 28 is superposed on one side of 0, and is provided on the cam 11 by rotating the elastic body 28 integrally with the locking plate 10 against the rotational bias by the bullet 26. 2nd stopper 11c
The first stopper 10b abuts the cam 11 to rotate the locking plate 10 which engages and holds the connecting pin 17 by rotating the operating lever 25. The elastic body 28 can contact the second stopper 11c of the cam 11 and can be automatically switched from the rotation biasing posture for restricting the movement to the coupling standby posture for solving the above-mentioned problems.

(E) Action When the work machine is to be connected to the hitch frame, the locking plate is in the connection standby position. In this state, the tractor is retracted and the hitch frame is raised via the link to connect it to the upper connection part. When the work machine is further raised, the connection pins at the lower part of the work machine are fitted into the openings of the grooves of the connection plate and the locking plate and sequentially intrude, and accordingly. The connecting pin rotates the locking plate to deeply engage the groove.

In this state, the first stopper provided on the locking plate is brought into contact with the cam and locked.

Also, when removing the work implement, the cam is disengaged from the first stopper provided on the locking plate by operating the operation lever, which is integrally provided with the cam below the operator's seat, from the rear of the machine to the front. , In this state, if the work implement is once raised and then lowered, first the work implement is grounded, and while the front part descends, the lower part is separated back and forth around the upper connection part, thereby connecting the connecting pins. When the locking plate pivots to the working machine side and the connecting pin completely comes out, the elastic body superposed on one side surface of the locking plate becomes the second stopper provided on the cam. When the abutment is in contact with the elastic plate, the elastic body is integrally provided on the locking plate.
The stopper is held in pressure contact with the stopper, so that the connection standby state is maintained.

That is, the rotation of the locking plate engaging and holding the connecting pin by rotating the operation lever from the front to the rear,
From the rotation biasing posture in which the first stopper contacts the cam and regulates its rotation, the rotation permitting posture in which the elastic body contacts the second stopper provided on the cam to enable rotation, that is, the working machine,
It can be possible to switch to a connection standby position in preparation for connection.

(F) Embodiment An embodiment of the present invention will be described with reference to the drawings. 1 is a tractor mission case, and a pair of left and right lower links 2 and 2 having front end portions connected to the lower portion thereof and a top link bracket 3 A hitch frame 5 is movably connected to the rear end of the top link 4 whose front part is connected to the hitch frame 5. The hitch frame 6 of the hitch frame 5 is formed by bending a pipe in an inverted U shape. An upper top hook 7 is fixed to the upper part of the connecting plate 8, and a connecting plate 8 fixed to the lower ends on both sides has a groove 8a having a rear opening and a lower pin 9 connecting the lower links 2 and 2. .

Reference numeral 10 is a locking plate having a groove whose lower portion is opened. The locking plate 10 is pivotally attached to the upper portion of the connecting plate 8 by a fulcrum pin 10a, and a step portion 10b is provided on the front surface of the upper portion. is there.

Numeral 11 is a cam rotatably attached to the front part of the connecting plate 8 by a support shaft 11a. The cam 11 is an operation lever described later.
It is pivotally attached to the lower part of 25 integrally and rotatably around the support shaft 11a of the connecting plate 8 in accordance with the turning operation of the operating lever 25. The upper surface of the corner 11b at the rear of the upper end of the cam 11 (the support shaft 1
The surface extending approximately perpendicular to the extension line of the diameter of 1a) receives the front surface of the stepped portion 10b (first stopper) formed on the upper portion of the locking plate 10 when locked, and the outside of this portion. The projection 11c provided on the has a slope 11d at the bottom,
The rear end surface of the protrusion 11c serves as a second stopper.

Reference numeral 12 is a rotary tiller, and a bracket 14 having an upper connecting pin 15 projecting from its front end is fixed to a top mast 13 standing upright at its front part, and a front part of a lower mast 16 projecting at its lower part. Is a connecting pin that is fitted into the groove 8a of the connecting plate 8.
17 is fixed.

Reference numeral 18 denotes a lift arm that rotates up and down by a hydraulic device, and although not shown, a lift rod lowers the lower link 2,
It is connected to the middle part of 2 and the mission case 1
The PTO shaft 19 protruding rearward from the clutch and the clutch 21 supported by the horizontal frame 5b below the hitch frame 5 are yoke joints.
A clutch mounted on an input shaft 23 that is linked by 20 and projects forward from the transmission case of the rotary tiller 12.
A clutch 22 is engaged with and disengaged from the clutch 21 on the front side, and a centering pin 22a is projectingly provided at the center of the clutch 22.

The left and right cams 11, 11 are integrally connected by a gate-type connecting rod 24, and the operation lever 25 screwed to one cam 11 is used.
Is loosely fitted in the guide groove 27a of the lever guide 27 attached to the hitch frame 6, and is connected to the operation lever 25 and the catch 10d projecting from the rear surface of the locking plate 10 by a tension spring 26. A direction in which the upper part of the locking plate 10 rotates forward by pivotally pivoting around a fulcrum pin 10a described later, that is, the locking plate 10 rotates following the connecting pin 17 when it is pulled out. Is urged to If the operating lever 25 and the lever guide 27 are attached to the left and right as in the above embodiment, the operation can be performed from either the left or right, but the operating lever 25 is attached to the middle part of the connecting rod 24, which corresponds to that. Let the lever guide
By fixing 27 to the hitch frame 6, the operation lever 25 can be integrated.

An elastic plate 28 whose center is fitted to the fulcrum pin 10a is fixed to the outer surface of the locking plate 10, and the tip of the elastic plate 28 projects from the step 10b toward the cam 11.

In the tractor described above, when the rotary tiller 12 is mounted on the hitch frame 5, the connecting pin 17 is fitted into the opening groove 8a of the connecting plate 8 as shown in FIG. It is also fitted and locked to 10c, and the operation lever 2
5 is located at the rear end of the guide groove 27a, and the projection 11c of the cam 11 is fitted into the step portion 10b of the locking plate 10 and locked by receiving the front surface of the step portion 10b on the upper surface. Cage,
The elastic plate 28 rides on the protrusion 11c of the cam 11.

Then, when removing the rotary tiller 12, hold the operation lever 25 by extending the hand backward from the driver's seat of the tractor,
When rotating from the position shown in FIG. 2 (a) to the position shown in FIG. 2 (b) against the tension spring 26 to the front release position, the upper and lower sides of the left and right cams 11, 11 which are integrated by the connecting rod 24 are connected. The corner portion 11b at the rear end is separated from the step portion 10b (first stopper) of the locking plate 10, and the tip end of the elastic body 28 is the protrusion portion 11 of the cam 11.
c Abut the rear end surface (second stopper) and hold the separated state. Next, when the rotary cultivator 12 in the ascending posture is lowered, first, the tail wheel 29 is grounded and the upper part is in the connected state, so the rotary cultivator 12 moves backward with the upper connecting pin 15 as the center. Pivot and lower connecting pin 17
Escape from the groove 8a of the connecting plate 8.

Along with that, the locking plate 10 also rotates in the direction of arrow A around the fulcrum pin 10a, and as shown in FIG.
The tip of 28 is rotated downward while slidingly contacting the rear end surface of the projection 11c, and finally comes off the projection 11c and overlaps with the outer surface of the cam 11 near the base as shown in FIG. Protrusion 11
Step 1 of the locking plate 10 on the rear end surface (second stopper) of c
The lower surface of 0b is overlapped, and the tension spring 26 is
Is rotated and urged in the counterclockwise direction in FIG.

In addition, when the rotary tiller 12 is connected to the hitch frame 5, when the previous rotary tiller 12 is removed,
The locking plate 10 urges the connecting plate 8 to rotate in the direction of the arrow A, so that the groove 8a of the connecting plate 8 opens into the opening groove of the locking plate 10.
Since the connecting pin 17 receiving posture facing 10c, that is, the standby state for connecting to the tractor of the rotary tiller 12, the top hook 7 is first hooked on the upper connecting pin 15 to raise the hitch frame 5, The rotary cultivator 12 pivots forward around the upper connecting pin 15 and lowers the connecting pin.
As shown by the arrow B in FIG. 2 (d), 17 penetrates into the groove 8a of the connecting plate 8 and the opening groove 10c of the locking plate 10, whereby the locking plate 10 rotates in the direction of the arrow B and is integrated with it. The tip of the elastic body 28 rides on the side surface of the projection 11c from the slope 11d of the cam 11, and when further rotated, the corner 11b of the cam 11 engages with the step 10b (first stopper) of the locking plate 10. Then, the locking plate 10 is received and the lock state is reached.
25 rotates backwards.

When such a work machine is attached or detached, the clutches 21 and 22 are in a meshed transmission state or in a disengaged non-transmission state.

(G) Effect of the Invention Since the present invention is configured as described above, the hitch frame 5 is brought closer to the working machine, and the connecting pin of the working machine is inserted into the groove 8a of the connecting plate 8.
When the working machine is connected to the hitch frame 5 by fitting 17 with each other, the opening groove 10c of the locking plate 10 also fits with the connecting pin 17 and is engaged in the process of the connecting pin 17 entering the groove 8a. Stop plate
When 10 rotates to reach the connection completion position, the operating lever 25 is rotated rearward around the support shaft 11a by the bullet 26, and the cam 11 provided on the operating lever 25 causes the locking lever 10 to move to the first position. 1 Stopper 10b is locked. That is, the locking plate 10 is reliably locked at the position where the connecting pin 17 is fitted by contact with the rotated cam 11, and the locking plate 10 rotates in the direction of arrow B to connect the connecting pin 17 to each other. It is possible to reliably prevent the work machine from coming off, that is, the work machine from coming off.

Further, when the working machine is detached from the hitch frame 5, the operating lever 25 is pivoted to the front side of the machine body to move the lever.
The cam 11 that is integrally provided below 25 rotates around the support shaft 11 forward, and the cam 11 and the first stopper of the locking plate 10
The pressed state with 10b is released, and the elastic body 28 superposed on one side surface of the locking plate 10 is pressed against the second stopper 11c provided on the cam 11. When the hitch frame 5 is separated from the working machine in this state, the connecting pin 17 is pulled out from the groove 8a of the connecting plate 8, whereby the locking plate 10 is rotated toward the working machine side to reach the connecting standby position. The tip of the locking plate 10 comes into contact with the stopper 11c, and the ammunition machine 26 moves the locking plate 10 into the second position.
Since it is pressed against the stopper 11c, the opening groove 10c of the locking plate 10 is constantly held in a standby position facing the groove 8a of the connecting plate 8, and when the working machine is connected to the hitch frame 5 next time, The stop plate 10 can be connected immediately without any operation for changing and adjusting the posture.

Therefore, simply by operating the operation lever 25 in one direction, the connecting plate is automatically moved to the connection standby position in which it can be rotated from the rotation biasing position that restricts the rotation of the locking plate 10 that holds the connection pin 17 engaged. Can be switched to each other.

[Brief description of drawings]

The drawings show an embodiment of the present invention, in which FIG. 1 is a front view of a hitch frame, and FIG. 2 (a) is a side view of essential parts showing a state in which a working machine is connected to the hitch frame. Figure (b) is a side view showing a state in which the working machine is ready to be removed (however, the lever guide is seen in a plan view), Figure (b-b) is a perspective view of the stopper portion, and Figure (c) shows that the working machine has started to be removed. FIG. 3D is a side view of the state, FIG. 3D is a side view showing a state immediately before the completion of removal of the working machine and a state in which the working machine is initially connected, FIG. It is a side view which shows the state which removed the rotary tiller from the hitch frame. 5 ... hitch frame, 6 ... hitch frame, 8 ... connecting plate, 10 ... locking plate, 8a ... groove, 10a ... fulcrum, 10b
…… First stopper, 11 …… Cam, 11c …… Second stopper, 12 …… Rotary tiller, 15 …… Upper connecting pin,
17 …… Connecting pin, 24 …… Connecting rod, 25 …… Operating lever, 26
…… ammo, 28 …… elastic body

Claims (1)

(57) [Claims] 1. A lower part of the hitch frame 5 in a tractor in which a hitch frame 5 is movably connected to a rear part of a machine body via a link so that a work machine can be attached to and detached from the hitch frame 5 by an upper part and a lower part. The connecting portion is rotatably pivotally attached to a connecting plate 8 having a groove 8a into which the connecting pin 17 of the working machine enters, and a portion vertically separated from the groove 8a of the connecting plate 8, and the connecting pin 17 is provided. In order to move in and out, a locking plate 10 having an opening groove 10c intersecting with the groove 8a is rotatably pivotally attached to a fulcrum 10a provided on the connecting plate 8, and the locking plate 10 and the connecting plate are connected. The operation lever 25 integrally provided with the cam 11 pivotally attached to the support shaft 11a provided on the plate 8 is provided opposite to one side of the connection plate 8 and is connected via the ammunition 26 to lock the same. The cam 11 is urged to rotate on the plate 10 in the direction in which the connecting pin 17 escapes.
An engaging and disengaging first stopper 10b is provided to prevent the connecting pin 17 that abuts against and engages with the
An elastic body 28 is superposed on one side of 0, and is provided on the cam 11 by rotating the elastic body 28 integrally with the locking plate 10 against the urging force of the bullet 26. 2nd stopper 11c
The first stopper 10b abuts the cam 11 to rotate the locking plate 10 which engages and holds the connecting pin 17 by rotating the operating lever 25. A working machine for a tractor characterized in that the elastic body 28 can automatically switch from a rotationally biasing posture that restricts movement to a coupling standby posture in which the elastic body 28 contacts the second stopper 11c of the cam 11 and is rotatable. Detachable device.