JPH0740805B2 - Agricultural work machine connection device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a farm work machine connecting device, and more particularly to a machine for automatically connecting a farm work machine to an agricultural tractor.

(Prior Art) Conventionally, as this type of agricultural machine coupling device, for example,
While the three-point link mechanism of the tractor, that is, the top link and the left and right lower links are connected with the quick coupler and suspended, the agricultural machine is installed by inclining forward and downward at a predetermined angle by a stand, and the upper part of the quick coupler is attached. While locking the connecting part of the upper part of the agricultural work machine in the forward tilted state to the locking part, the quick coupler is raised and rotated by the three-point link mechanism to lift the agricultural work machine and pull it toward the tractor side. There is a connection system in which the left and right lower connecting portions of the agricultural work machine are connected to the left and right lower engaging portions.

(Problem to be Solved by the Invention) According to the configuration of the conventional connection system, it takes a troublesome work to bring the agricultural work machine into the forward tilted posture by the stand, and
Depending on the agricultural work machine, it is not possible to attach the stand, so that the agricultural work machine cannot be tilted forward.

Although it is possible to manually tilt the agricultural work machine without using a stand, it is extremely difficult and troublesome to convert the agricultural work machine that is extremely heavy in weight to such a posture. .

Therefore, the present invention has been made in view of such a point, and when the agricultural working machine is connected, the top link is extended and the quick coupler is pivotally inclined toward the agricultural working machine side so that the upper locking portion is located on the agricultural working machine side. After connecting the farming machine to the quick coupler, the extended top link is automatically contracted so that the farming machine can be set to the work posture, which allows the stand to be used again without using the stand. It is an object of the present invention to provide an agricultural work machine connecting device that can be easily connected to a quick coupler without installing any agricultural work machine that cannot be used in a forward leaning posture.

(Means for Solving Problems) The agricultural machine coupling device of the present invention includes a three-point link mechanism including a retractable top link and left and right lower links provided on a tractor to be lifted and lowered, and a three-point link mechanism. A quick coupler that is rotatably connected in the front-rear direction and has a three-point locking portion, an agricultural work machine that has a three-point connecting portion that is connected to the three-point locking portion of this quick coupler, and the agricultural machine for the quick coupler. When connecting the farm work machine coupling device, the top link is extended to tilt the quick coupler toward the farm work machine, and the top link is contracted when the farm work machine is connected to the quick coupler. In the above, the top link of the three-point link mechanism includes a first screw rod having a connecting body for connecting to the tractor and a second screw rod having an inner shaft. An outer body having a link body in which a screw rod is connected so as to be adjustable forward and backward in the axial direction, and a connecting body that is fitted in the inner shaft of the link body so as to be forward and backward in the axial direction and connected to the agricultural work machine at an outer end portion It has a shaft, a lock pin, and a rotating body that is rotatably supported by a lock pin and an engaging portion that engages with and disengages from the lock pin. The outer shaft pushed and contracted by the inner shaft is locked and locked. A lock releasing means for releasing the lock body, a spring for biasing the rotating body of the lock releasing means so that the engaging portion of the rotating body is always engaged with the lock pin, and the rotating body is locked against the spring. And an operation unit that is rotated in the releasing direction.

(Operation) In the agricultural work machine connecting device of the present invention, when the quick coupler is connected to the three-point link mechanism of the tractor, and the rotating body of the top link of the three-point link mechanism is rotated by the operating portion, the rotating body is rotated. Is rotated about the support shaft against the spring, and the engaging portion of the rotating body is disengaged from the lock pin to unlock the outer shaft. Then, the quick coupler is tilted by its own weight toward the agricultural work machine side about the connecting portion with the left and right lower links, and the outer shaft is extended outward along the inner shaft in the axial direction. The locking part on the top of the quick coupler is projected to the farm work machine side.

Next, when the three-point link mechanism of the tractor is raised and rotated,
By the upward arc movement of the quick coupler, the upper locking part is first engaged with the upper connecting part of the agricultural work machine, and the upper connecting part of the quick coupler is rotated upward to move the upper connecting part. While the agricultural work machine is being lifted via this, the agricultural work machine is pulled toward the front of the tractor side around the upper connecting part that is engaged with the upper locking part, and the agricultural work is carried on the left and right lower locking parts of the quick coupler. The left and right lower connecting parts of the machine are automatically engaged and connected.

Next, when the three-point link mechanism of the tractor is rotated downward,
The agricultural work machine is landed through this quick coupler, and the agricultural work machine is tilted forward and downward around the left and right lower connecting parts connected to the left and right lower locking parts of the quick coupler, and the agricultural work machine is also tilted. The upper coupling part of the quick coupler pushes the upper locking part of the quick coupler forward.

Then, the quick coupler is rotated forward around the connecting portion with the left and right lower links, and the outer shaft is pushed by this quick coupler to slide inward in the axial direction along the inner shaft. Contracted,
The outer shaft is contracted to a predetermined position, and the outer shaft is locked to the inner shaft by a rotating body urged by a lock pin of a lock releasing means and a spring.

Therefore, the contracted top link has a length during work, and the top link and the left and right lower links support the quick coupler that connects the agricultural work machines. Further, when it is necessary to adjust the length of the top link, when the link main body is adjusted and operated, the first screw rod and the second screw rod are axially advanced and retracted with respect to the link main body, The top link is easily adjusted and set to a predetermined length, and the top link variably sets the agricultural work machine to an appropriate work posture.

(Embodiment) An embodiment of the present invention will be described below with reference to the accompanying drawings.

1 is a tractor, and a connecting frame 2 is provided on the upper rear end of the tractor 1.
Is fixed to the connecting frame 2, and the connecting body 4 at the base end of the top link 3 is connected to the connecting frame 2 by a connecting pin 5 so as to be vertically rotatable. Further, connecting pieces 6 are respectively provided at lower portions on both sides of the rear end of the tractor 1, and the base ends of the left and right lower links 7 are connected to the left and right connecting pieces 6 by connecting pins 8 so as to be vertically rotatable. The left and right lower links 7 and the top link 3 constitute a three-point link mechanism 9.
A base end of a lift arm 11 is pivotally mounted on the rear end of the tractor 1 via a lift shaft 10 so as to be vertically rotatable, and a tip end of the lift arm 11 is supported via a support shaft 12. The lower link 7 is rotatably rotatably attached to the lower end of a lift rod 13 rotatably rotatably attached by a support shaft 14.

Next, the top link 3 includes a first screw rod 15 and a second screw rod 15.
The screw rod 16 and a link body 20 comprising a turnbuckle 19 provided with a nut body 18 having a handle 17 in which the screw rods 15 and 16 are screwed and connected so as to be adjustable forward and backward in the axial direction. A lock nut 22 having a handle 21 is screwed to the first screw rod 15 so as to be able to move forward and backward by rotation, and an insertion hole into which the connecting pin 5 is inserted at the base end portion of the first screw rod 15. The connecting body 4 having 4a is integrally connected.

An inner shaft 23 having a polygonal cross-section is integrally connected to the tip of the second screw rod 16 in the axial direction, and a flange-shaped stopper 24 is integrally provided on the outer periphery of the tip of the inner shaft 23. In addition, a hollow cylindrical hollow accommodating portion 25, which is open to the outside, is bored in the center of the inner shaft 23 in the axial direction.

An outer shaft 26 having a polygonal hollow section is inserted into the outer portion of the inner shaft 23 so as to be slidable in the axial direction, and stoppers of the inner shaft 23 are provided above and below the proximal end portion of the outer shaft 26. A stopper 27 that is locked to 24 is fixed, and a connecting body 29 having an insertion hole 28 is fixed to the tip end portion of the outer shaft 26.
A locking surface 30 for the opening surface of the hollow accommodating portion 25 is formed on the end surface portion of the base end portion of 29.

A support shaft 32 is provided on the left and right side plate portions 31 at the base end portion of the outer shaft 26 so as to project outward, and the left and right support shafts 32 have a pivoting body 33 formed in a U-shaped cross section. Is rotatably supported in the vertical direction. This rotating body 33 is
Left and right side plates 34 pivotally supported by the left and right support shafts 32.
The left and right side plates 34 are formed with cams 35 inclined toward the base end side at the lower ends of the left and right side plates 34.
Engagement recesses 36 are formed on the left and right side plates 34 in the vicinity of the lower end of 35 as engagement parts, opening downward.

Further, a cutout recess 38 is formed at the base end of a top plate 37 in which the upper ends of the left and right side plates 34 of the rotating body 33 are continuously provided.
A handle 39 as an operating portion extending in the axial direction is fixed to one side portion of the distal end portion of the support rod 40, and the support rod 40 protruding outward in the left-right direction from the base end portion of the handle 39 and the outer shaft 26. Support rod 41 that protrudes laterally outward from the lower part of the middle of the
A coil spring 42 is stretched between and, and the rotating body 33 is urged by the coil spring 42 so as to rotate downward about the left and right support shafts 32.

Further, a locking rod 43 as a lock pin is projected at a base end portion of the inner shaft 23 in a direction orthogonal to the inner shaft 23, and right and left of the rotating body 33 with respect to left and right protruding portions of the locking rod 43. The engagement recess 36 is engaged and disengaged by the rotation of the rotating body 33 so as to be engageable and disengageable. Then, the outer shaft 26 is locked by the locking rod 43 serving as the lock pin and the rotating body 33 having the handle 39 serving as an operating portion that rotates around the left and right support shafts 32, and the lock is performed. A lock releasing means A for releasing the lock is configured.

In addition, the outer shaft is provided at one end of the locking rod 43.
An L-shaped guide rod 45 is integrally fixed to an upper portion of one side of the guide rod 26 and has an upper portion having a guide 44 protruding in a direction orthogonal to the outer shaft 26. Then, the rotating body 33 is supported by the handle 39 on the left and right supporting shafts.
The outer shaft 26 is rotated around the 32 in the unlocking direction against the coil spring 42, and the rotating body 33 is unlocked and raised on the outer shaft 26. When extended from, the rotating body 33 is engaged with the guide 44, and the guide 44 causes the rotating body 33 to rotate downward about the left and right support shafts 32.

Further, a coil spring 46 is housed in the hollow housing portion 25 of the inner shaft 23.
The inner end of 46 is locked to the locking wall 47 in the hollow housing portion 25, and the outer end of this coil spring 46 is locked to the locking surface 30 of the outer shaft 26. Then, the outer shaft is formed by the coil spring 46.
26 is always urged to project to the outside of the inner shaft 23.

Also, 48 is a quick coupler, this quick coupler
48 has a connecting frame 49 formed by bending a pipe material into a substantially mountain shape, and a connecting plate 50 as a lower engaging portion is provided at the left and right lower end portions extending below the connecting frame 49. The left and right connecting plates 50 are fixed to each other, and the left and right connecting plates 50 extend in the front-rear direction, and the rear end has an engaging recess 51 that opens rearward. A lower pin 52 is horizontally projected outward from the lower end.

In addition, the pins protruding above the front ends of the left and right connecting plates 50.
A lock arm 54 is pivotally attached to 53 in a vertically rotatable manner,
The engaging recesses 51 are provided at the rear ends of the left and right lock arms 54.
A locking projection 55 that projects inward is formed, and a guide surface 56 that is inclined downward is formed at the outer edge of the locking projection 55, and the front end portions of the left and right lock arms 54 are arranged in the vertical direction. The handle 57 of is fixed.

Further, a support shaft 58 is projected in the middle of the upper portion of the left and right connecting plates 50, and one end of a spring 59 such as a spiral spring wound around the support shaft 58 is locked to the pin 53, The other end is locked to the rear end of the lock arm 54. The spring 59 causes the lock arms 54 to rotate about the pins 53, and the locking projections 55 thereof are always projected into the engaging recesses 51. Incidentally, 60 is a stopper of the lock arm 54.

A pair of connecting plates 61 are fixed to the top of the connecting frame 49 with a predetermined space therebetween, and mounting holes 62 are formed in the front and rear portions of the upper portions of the pair of connecting plates 61. ing. Further, a hook 63 as an upper locking portion is fixed to the lower ends of the pair of connecting plates 61 and the top of the connecting frame 49, and the hook 63 has a locking recess 64 formed at a substantially middle upper portion. , This locking recess 64
A guide surface 65 is formed at the upper edge of the rear side so as to be inclined rearward and upward. The left and right connecting plates 50 of the connecting frame 49 and the hooks 63 form a three-point locking portion.

Further, the support arms 66 are respectively fixed to the inner portions of the lower portions on both sides of the connection frame 49.
A connecting body 68 is pivotally mounted between the tip portions of the two by means of left and right bolts 67 so as to be swingable vertically and horizontally. This connector 68
Is a hollow cylindrical support tube 69 having the bolts 67 on the left and right.
A hollow cylindrical sliding cylinder 70 is slidably inserted into the support cylinder 69 through a guide and a guide groove, and the power transmission shaft 71 of the power transmission shaft 71 is inserted in the sliding cylinder 70. A hollow spline shaft cylinder of one universal joint 72 is rotatably fitted and supported via bearings provided at the front and rear, and guides a spline hole 73 formed of a large number of splines formed in the axial direction of the inner wall of the spline shaft cylinder. The mouth is opened at the rear end,
A coil spring is interposed between the support cylinder 69 and the sliding cylinder 70.

Then, the one universal joint 72 is fixed to the outer end portion of the outer cylinder 74, and an inner cylinder 75 fixed in the axial direction and movable back and forth only in the axial direction is inserted into the outer cylinder 74. The other universal joint 76 is connected to the outer end of the inner cylinder 75. The power transmission shaft 71 is composed of the one universal joint 72, the outer cylinder 74, the inner cylinder 75 and the other universal joint 76.

Reference numeral 77 denotes an agricultural work machine, which has a main frame 78 extending in the left-right direction, and a chain case 79 and a bracket (not shown) are attached to both ends of the main frame 78 so as to face each other. The rotary working body 80 is rotatably provided between the lower ends of the chain case 79 and the bracket, and the cover body 81 covering the upper part of the rotary working body 80 is fixed between the chain case 79 and the bracket. A leveling body 82 is provided at the rear end of the cover body 81 so as to be vertically rotatable.

Further, a mission case 84 having a mission 83 built therein is provided in an intermediate portion of the main frame 78, and an input shaft 85 composed of a spline shaft of the mission 83 is rotatably projected forward, and the input shaft 85 is The guide port of the connecting body 68 is adapted to be spline-fitted in the spline hole 73 of the spline shaft cylinder from the axial direction. Further, a mast 86 is projected forward from the upper portion of the mission case 84, and an upper engaging pin 87 as a connecting portion for engaging the hook 63 in a freely detachable manner is horizontally provided between the front end portions of the mast 86. There is. In addition, the lower arms are moved forward from both sides of the main frame 78.
Each of the left and right lower arms 88 is projected, and a lower engaging pin 89 as a connecting portion that engages with the left and right engaging recesses 51 in a freely detachable manner in the left and right engaging recesses 51 horizontally projects outward. Has been done. The upper engaging pin 87 and the left and right lower engaging pins 89 form a three-point connecting portion.

Next, the operation of the above configuration will be described.

The left and right lower pins 52 of the connecting frame 49 are rotatably connected to the tip ends of the left and right lower links 7 of the tractor 1, and
The attachment hole 62 at a selected position in the connection plate 61 of the connection frame 49 is rotatably connected to the connection body 29 at the tip of the top link 3 of the tractor 1 by the connection pin 90. Further, the spline shaft 92 of the other universal joint 76 of the power transmission shaft 71 is spline-fitted to the power take-off shaft 91 of the tractor 1. As a result, the quick coupler 48 is connected to and supported by the three-point link mechanism of the tractor 1, and the quick coupler of the power takeoff shaft 91 of the tractor 1 is also supported.
The power transmission shaft 71 is connected between the power transmission shaft 48 and the power transmission shaft 48.

Next, in the top link 3 of the three-point link mechanism 9, when the rotating body 33 is rotated by the handle 39 about the left and right support shafts 32 against the coil springs 42 in the clockwise direction in FIG. The engagement recess 36 of the rotating body 33 is the link body.
The lock rods 43 on the left and right sides of the link body 20 are disengaged, and the inner shaft 23 and the outer shaft 26 of the link body 20 are unlocked.

The quick coupler 48 is tilted by its own weight toward the agricultural work machine side about the lower pins 52 of the left and right lower links 7, and the outer shaft 26 is axially moved along the inner shaft 23 by the restoring force of the coil spring 46. Of the power transmission shaft 71, the outer cylinder 74 is pulled out from the inner cylinder 75 and expanded with the expansion of the top link 3. Therefore, the top link 3 causes the quick coupler 48 to extend. Is tilted rearward in the clockwise direction in FIG. 1 about the left and right lower pins 52, and the hook 63 on the upper portion of this quick coupler 48 is rotated.
Is projected to the farm work machine 77 side.

Further, when the outer shaft 26 is projected outward, the rotating body 33 pulled up on the outer shaft 26 engages with the guide 44 of the guide rod 45 and is prevented from moving outward. Since the outer shaft 26 continues to project outward, the rotating body 33 is pushed by the guide 44 as the outer shaft 26 moves, and the rotating body 33 is pushed.
Is rotated downward about the left and right support shafts 32 in the counterclockwise direction in FIG. 2 to be superimposed on the outer shaft 26,
The rotating body 33 is supported by the coil spring 42.

Next, the tractor 1 is retracted toward the agricultural working machine 77 arranged at the rear part of the tractor 1, and the hooks on the upper portion of the quick coupler 48 connected and supported by the three-point link mechanism 9 are hooked.
When 63 faces the upper engaging pin 87 of the mast 86 of the agricultural work machine 77, the retraction of the tractor 1 is stopped.

When the lift arm 11 of the tractor 1 is rotated upward,
The quick coupler 48 is lifted and rotated by the circular motion by the three-point link mechanism 9, and the upper engagement pin 87 of the upper part of the agricultural working machine 77 is engaged with the guide surface 65 of the hook 63 on the upper part of the quick coupler 48. At the same time, the upper engaging pin 87 moves from its guide surface 56 to the engaging recess 64 of the foot 63.
Engaged in. Then, when the quick coupler 48 is further rotated upward, the upper working pin 77 is lifted upward by the upper hook 63 via the upper engaging pin 87, and the upper engaging pin locked to the hook 63. This agricultural work machine 77 is drawn toward the front of the tractor 1 side around 87, and the left and right lower engagement pins 89 of the agricultural work machine 77 are automatically inserted into the engaging recesses 51 in the left and right connecting plates 50 of the quick coupler 48. The input shaft 85 of the agricultural work machine 77 is automatically spline-fitted from its guide port into the spline hole 73 of the spline shaft cylinder of the connector 68 that is engaged and locked and is suspended by the connection frame 49 of the quick coupler 48. Are combined.

When the left and right lower engagement pins 89 are engaged and locked in the engagement recesses 51 of the left and right connecting plates 50, the guide surfaces 56 of the locking projections 55 of the lock arms 54 of the left and right connecting plates 51 are left and right. Lower engaging pins 89 of the lock arm 54 contact the lower engaging pins 89, and the left and right lower engaging pins 89 push the locking projections 55, so that the lock arm 54 moves to the pin 58.
1 is rotated counterclockwise in FIG. 1 against the spring 59, the left and right lower engaging pins 89 are fitted into the engaging recesses 51, and the restoring force of the spring 59 causes the lock arm 54 to move. 1 is rotated around the pin 58 in the clockwise direction in FIG. 1, and the locking projection 55 is engaged with the rear portion of the lower engagement pin 89 so as to close the engagement recess 51.

Further, the connecting body 68 of the one universal joint 72 is
When the input shaft 85 is spline-fitted in the
When the spline hole 73 of the spline shaft cylinder of 68 and the axis of the input shaft 85 do not match, the tip end of the input shaft 85 is inserted into the guide port of the connecting body 68, and the connecting body 68 moves vertically. By swinging in the left-right direction, their mutual axial centers are automatically aligned, so that the input shaft 85 is automatically spline-fitted into the spline hole 73 of the spline shaft cylinder.

In this way, the four-point connecting portion on the agricultural machine 77 side is automatically connected to the four-point connecting portion on the quick coupler 48 side.

Next, when the three-point link mechanism 9 of the tractor 1 is rotated downward, the farm work machine 77 is landed via the quick coupler 48, and the farm work machine 77 is connected to the left and right engaging recesses 51 of the quick coupler 48. The lower engaging pin 89 of the is tilted downward toward the front and the
The connecting portion 87 on the upper portion of 77 pushes the connecting portion on the upper portion of the quick coupler 48 forward.

Then, the quick coupler 48 is rotated forward around the lower pin 52 that connects the left and right lower links 7, and the outer shaft 26 is pushed by the connecting pin 90 on the upper portion of the quick coupler 48.
While compressing the coil spring 46, the inner shaft
It is slid and contracted inward in the axial direction along 23.

Then, the left and right cams 35 of the rotating body 33 of the outer shaft 26 hit the locking rod 43, the left and right cams 35 ride up the locking rod 43 against the coil springs 42, and the rotating body 2, the left and right cams 35 pass through the locking rods 43, and the left and right engaging recesses 36 of the rotating body 33 are locked by the locking rods 43.
2 and the rotating body 33 is rotated counterclockwise in FIG. 2 by the restoring force of the coil spring 43, and the left and right engaging recesses 36 are automatically fitted into the locking rod 43 to rotate the rotating body.
33 is locked.

Therefore, the quick coupler 48 is rotated counterclockwise in FIG. 1 about the left and right lower pins 52, and the top link 3 is automatically contracted. Thus, the top coupler 3 and the left and right lower links 7 support the quick coupler 48 to which the agricultural work machine 77 is connected.

When the length of the top link 3 needs to be adjusted, when the nut body 18 of the link body 20 is rotated, the first screw rod 15 and the second screw rod 15 are moved with respect to the nut body 18.
16 are respectively adjusted back and forth in the axial direction, and this top link 3 is easily adjusted to a predetermined length, and at this top link 3, the quick coupler 48 has left and right lower pins 52.
The top link 3 is rotatably adjusted in the front-rear direction and is set to have a predetermined length, so that the farm work machine 77 is variably set to an appropriate work posture by the top link 3.

Then, as the tractor 1 advances, the agricultural work machine 77 is towed through the quick coupler 48, and the power from the power takeoff shaft 91 of the tractor 1 is transmitted to the mission 83 via the power transmission shaft 71 and the input shaft 85. The rotary work body 80, which is linked to the mission 83 through the output shaft in the main frame 78 and the interlocking medium in the chain case 79, is rotationally driven by the output from the mission 83, and is paired by the rotary work body 80. Earth work is performed.

(Effect of the Invention) According to the present invention, the top link of the three-point link mechanism is capable of axially advancing and retracting the first screw rod having the connecting body that is connected to the tractor and the second screw rod having the inner shaft. To the lock pin and the lock pin, the outer shaft having a link body connected to the Lock releasing means for locking and releasing the outer shaft, which has a rotating body rotatably and rotatably supported to form a disengageable engaging portion, and is contracted by being pushed into the inner shaft, and the lock. A spring for urging the rotating body of the releasing means to constantly engage the engaging portion of the rotating body with the lock pin, and a direction for unlocking the rotating body against the spring. Since it has an operating part for rotating the rotating machine, when the agricultural working machine is connected, the rotating body of the lock releasing means is rotated in the lock releasing direction around the support shaft by the operating part.
The rotating body can be disengaged from the lock pin and the outer shaft can be easily unlocked, and the outer shaft can be slid along the inner shaft to extend the top link. The coupler is rotated and tilted to the farm work machine side,
It is possible to automatically project the connecting portion on the upper side of the quick coupler to the farm working machine side to prepare for connection pulling up of the upper connecting portion on the farm working machine side.

Also, after connecting the agricultural work machine, the agricultural work machine landed by the three-point link mechanism of the tractor leans forward and the quick coupler is pushed at the upper connection part of the agricultural work machine, so that the quick coupler is moved to the tractor side. It can be rotated and slide the outer shaft along the inner shaft to the set position at the top of this quick coupler, and the outer shaft can be automatically locked to the inner shaft by the unlocking means, and thus expanded. The top link can be automatically contracted so that the farm work machine can be surely converted and set to the work posture, without using a stand that supports the farm work machine, and any farm work machine that cannot use the stand is particularly It can be easily connected to a quick coupler without installing it in a forward leaning position.

Further, since the top link has a link body in which a first screw rod having a connecting body and a second screw rod having an inner shaft are connected so as to be adjustable forward and backward in the axial direction, the first main body is operated by operating the link body. By adjusting the screw rod and the second screw rod in the axial direction, it is possible to easily adjust and set the agricultural work machine to an appropriate work posture.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a side view showing a state in which a working machine is connected to a tractor, FIG. 2 is an enlarged side view of a top link, and FIG. Plan view,
FIG. 4 is a sectional view taken along line a-a in FIG. 1 ... tractor, 3 ... top link, 9 ... three-point link mechanism, 4,29 ... coupling body, 15 ... first screw rod, 16 ...
2nd screw rod, 20 …… link body, 23 …… inner shaft, 26 …… outer shaft, 33 …… rotating body, 36 ……
Engagement part, 39 …… Operating part, 42 …… Spring, 43 …… Lock pin, 48 …… Quick coupler, 50,63 …… Three-point locking part, 77 …… Agricultural work machine, 87,89 …… Three Point connection part, A ... Lock release means.

Claims (1)

[Claims] 1. A three-point link mechanism composed of a retractable top link and left and right lower links provided on a tractor so as to be lifted and lowered, and a three-point locking portion which is rotatably connected to the three-point link mechanism in the front-rear direction. A quick coupler having, a farming machine having a three-point connecting portion connected to a three-point locking portion of the quick coupler, and the top link is extended when the farming machine is connected to the quick coupler. In the agricultural work machine connecting device, wherein the quick coupler is rotated and inclined toward the agricultural work machine side, and the top link is contracted when the agricultural work machine is connected to the quick coupler, the top link of the three-point link mechanism is the tractor. A link book in which a first screw rod having a connecting body to be connected to the second screw rod and a second screw rod having an inner shaft are connected so as to be adjustable forward and backward in the axial direction. Body, an outer shaft having a connecting body that is fitted in the inner shaft of the link body so as to be able to move back and forth in the axial direction, and that is connected to the agricultural work machine at the outer end, and the lock pin and the lock pin. Lock releasing means for locking and unlocking the outer shaft which has a rotating body rotatably and rotatably supported and is pushed into the inner shaft and contracted, and a lock releasing means of the lock releasing means. A spring for urging the rotating body to constantly engage the engaging portion of the rotating body with the lock pin;
An operating unit for rotating the rotating body in the unlocking direction against the spring.