JPH0735530Y2 - Tail wheel floating device of rotary tiller - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tail wheel floating device of a rotary tiller.

2. Description of the Related Art Conventionally, a rotary tiller used in connection with a rear part of a mobile agricultural machine is generally equipped with a tail wheel floating device as described in Japanese Utility Model Publication No. 61-25611.

Here, in the tail wheel floating device described in Japanese Utility Model Publication No. 61-25611, as shown in FIGS. 5 and 6, the mast 2 fixed to the rotary body 1 is connected to one end of the swing arm 3. One end of the link 4 is rotatably connected, and a pin 5 fixed to the other end of the link 4 is swingably penetrated into an elongated hole 6 formed in the swing arm 3. A stopper 7 is rotatably attached to the swing arm 3. Then, by pinching the pin 5 between the holding surface 8 formed on the stopper 7 and the upper end of the elongated hole 6,
A tail wheel support 10 for supporting the tail wheel 9 with the three-bar linkage composed of the mast 2, the swing arm 3, and the link 4 fixed.
To lock the floating state of the tail wheel 9.

When the shape accuracy of the holding surface 8, the dimensional accuracy of the elongated hole 6, and the mounting accuracy of the stopper 7 are low, the pin 5 is interposed between the holding surface 8 and the upper end of the elongated hole 6. When the pin is held, a gap is created between the outer peripheral surface of the pin 5 and the holding surface 8, so that the three-joint link mechanism cannot be securely fixed, and vibration or noise is generated during the work.

Even when the shape accuracy of the holding surface 8 and the dimensional accuracy of the elongated hole 6 during manufacturing are high, the holding surface 8 and the outer peripheral surface of the pin 5 are worn by long-term use, and the long distance between the holding surface 8 and When the pin 5 is held between the upper end of the hole 6 and the pin 5, a gap is generated between the outer peripheral surface of the pin 5 and the holding surface 8, and vibration or noise is generated during the work.

Means for Solving the Problem A tail wheel support body for supporting a tail wheel is vertically rotatably connected to a rotary machine body, and a swing arm and a tail wheel support are vertically oscillatably connected to the rotary machine body. And a rotary body and an engaging portion that locks the swing motion of the swing arm by engaging with the lock body and the rotary machine body and the swing body. In a tail wheel floating device of a rotary cultivator provided between an arm and the arm, the tail wheel floating device is movable along an oscillating direction of the oscillating arm and can be fixed at an arbitrary position, and the lock body and the engagement at the time of engagement. The rotary machine body is provided with a clearance eliminating member that causes the swing arm to swing in a direction that eliminates the clearance between the rotary body and the portion.

Operation When the clearance eliminating member is operated to swing the swinging arm, even if a dimensional error during manufacturing or wear due to use occurs, the gap between the lock body and the engaging portion during engagement is increased. The gap is eliminated, the lock body and the engaging portion are securely engaged with each other, and vibration and noise during the work are prevented.

Embodiment An embodiment of the present invention will be described with reference to FIGS. 1 to 4. At the rear of the tractor 11, a pair of left and right lower links 12
A rotary tiller 15 is connected via a three-point link mechanism 14 composed of a top link 13 and a top link 13. Further, the lower end of the lift arm 16 and the lower link which are vertically rotated by driving a hydraulic device (not shown) of the tractor 11.
A lift rod 17 is connected between the approximately central portion of 12 and the lift rod 17.

To the rotary machine body 18 of the rotary tiller 15, a front end portion of a tail wheel support body 19 extending rearward is connected by a support pin 20 so as to be rotatable in the vertical direction. A tail wheel 22 for adjusting the working depth by the rotary tiller 21 is attached to the end. Further, to the rotary machine body 18, a front end portion of a swing arm 23 extending upward in the rear portion is connected by a support pin 24 so as to be swingable in the vertical direction, and the rear end portion of the swing arm 23 and the tail wheel. A plowing depth adjusting rod 25 is connected to the rear end of the support 19 by support pins 26 and 27. The tilling depth adjusting rod 25 is provided with a screw shaft and is configured to be expandable and contractable by rotating the handle 28.

Next, a support pin 29 having a horizontal axis in the horizontal direction is attached to the rotary machine body 18 so as to be rotatable around the axial center, and a lock body 30 is fixed to a substantially central portion of the support pin 29. . A lever 31 is fixed to one end of the support pin 29, and an operation lever 32 for rotating the lock body 30 about the axis of the support pin 29 is fixed to the lever 31 with a bolt 33. ing. Also, the lock body 30
A cylindrical tubular body 34 is fixed to the cylindrical body 34, and a pin body 36 that comes into contact with and separates from a release pin 35 fixed to the swing arm 23 in accordance with the rotating operation of the lock body 30 is attached to or detached from the cylindrical body 34. It is installed freely. Further, the lock body 30 is provided with an engagement recess 38 that engages and disengages with an engagement pin 37 that is an engagement portion fixed to the swing arm 23 in accordance with the rotation operation of the lock body 30. A guide surface 39 that contacts the outer peripheral surface of the dowel pin 37 is formed.

Next, one end is supported by the rotary machine body 18 at a fulcrum A, and the other end is supported by the lever 31 at a fulcrum B.
A spring 40 supported by the is provided. This spring 40 has a direction in which the engagement recess 38 engages with the engagement pin 37 when the fulcrum B is located above the line L with respect to the line L connecting the center of the support pin 29 and the fulcrum A (arrow). a direction)
When the fulcrum B is located below the straight line L, the lock body 30 is urged toward the direction (arrow b direction) in which the pin body 36 is pressed against the release pin 35. Is configured. Further, the release pin 35 causes the lock body 30 together with the pin body 36 to move around the axis of the support pin 29 when the swing arm 23 swings to the position shown by the chain double-dashed line in FIG. It is configured to rotate in the a direction, and the fulcrum B of the spring 40 reaches above the straight line L in the middle thereof.

Here, a projection piece 41 is fixed to the rotary machine body 18, and the projection piece 41 is screwed into a pair of nuts 42 and is capable of moving forward and backward along the swing direction of the swing arm 23. 43 is installed. A stopper 44, which is a clearance eliminating member that abuts the lower side surface of the swing arm 23, is fixed to one end of the bolt 43 on the side facing the swing arm 23.

In such a structure, during normal rotary tilling work, the tail wheel support 19 is brought to the lowered position by bringing the swing arm 23 into contact with the stopper 44, and the lock body 30 is rotated. The engagement recess 38 is engaged with the engagement pin 37. In this state, the urging force of the spring 40 acts in a direction to engage the engagement recess 38 with the engagement pin 37, so that the engagement state between the engagement recess 38 and the engagement pin 37 is maintained. Then, the engaging concave portion 38 is engaged with the engaging pin 37 to lock the swinging motion of the swinging arm 23, and thereby the vertical swinging motion of the tail wheel support 19 is also locked. The floating state of the wheel 22 is locked.

Next, a case where the rotary tilling work is started from the edge will be described. First, the rotary tiller 15 is raised by driving the hydraulic device of the tractor 11, and the operation lever 32 is rotated downward. By rotating the operating lever 32 downward, the lock body is integrated with the operating lever 32.
30 rotates around the axis of the support pin 29 in the direction of arrow b, and the engagement between the engagement recess 38 and the engagement pin 37 is released. When the lock body 30 rotates in the direction of arrow b and the fulcrum B of the spring 40 moves below the straight line L, the urging force of the spring 40 causes the lock body 30 to rotate in the direction of arrow b due to the action beyond the fulcrum. The pin body 36 is kept in contact with the release pin 35 even if the user releases his / her hand from the operation lever 32.

After releasing the rocking state of the swinging arm 23 by the lock body 30 in this way, the rotary tiller 15 is lowered by driving the hydraulic device of the tractor 11 and the tail wheel 22 is ridged 45.
On top of. When the rotary tiller 15 is subsequently lowered, the tail wheel support 19 rotates relatively upward around the axis of the support pin 20, and the swing arm 23 moves the support pin 24.
It swings about the axis of the shaft toward the position shown by the chain double-dashed line in FIGS. On the other hand, the release pin 35 that is in contact with the pin body 36 moves upward as the swing arm 23 swings, and the release pin 35 rotates the lock body 30 through the pin body 36 around the axis of the support pin 29. To rotate in the direction of arrow a. When the lock body 30 rotates to a position where the fulcrum B of the spring 40 is above the straight line L, the urging force of the spring 40 changes to the direction of rotating the lock body 30 in the arrow a direction, and the lock body 30 moves. The guide surface 39 contacts the outer peripheral surface of the engaging pin 38 by automatically rotating in the direction of arrow a by the urging force of the spring 40.

If the tractor 11 is moved forward while the rotary tiller 21 is driven after the rotary tiller 21 comes into contact with the field scene near the ridge, the tail wheel 22 is disengaged from the ridge and comes into contact with the field scene. At this time, the tail wheel support 19 rotates downward about the axis of the support pin 20 and the swing arm 23 swings downward about the axis of the support pin 24. Further, when the swing arm 23 swings downward, the engagement pin 37 is slightly pushed down the lock body 30 and displaced while being in contact with the guide surface 39, and eventually the swing arm 23 contacts the stopper 44. In contact with each other, the downward swinging motion is stopped, and the engaging recess 38 of the lock body 30 engages with the engaging pin 37, so that the swinging arm 23 is locked. The engagement pin 37
In the state where the lock body 30 is slightly pushed down by, the fulcrum B of the spring 40 is located above the straight line L, and the biasing force of the spring 40 causes the lock body 30 to rotate in the direction of arrow b. It does not work.

Next, due to dimensional error during manufacturing and wear due to use, a gap is generated between the engagement recess 38 and the engagement pin 37 when the engagement recess 38 and the engagement pin 37 are engaged with each other. In this case, the bolt 43 is adjusted back and forth, and the adjustment causes the stopper 44 in contact with the swing arm 23 to swing the swing arm 23. By swinging the swing arm 23 by the stopper 44, the gap between the engagement recess 38 and the engagement pin 37 can be eliminated and the engagement recess 38 and the engagement pin 37 can be reliably engaged. it can. Then, the vibration and noise during the work, which are generated due to the existence of the gap between the engagement recess 38 and the engagement pin 37, are prevented. It should be noted that the adjustment by the stopper 44 for eliminating the gap between the engagement recess 38 and the engagement pin 37 can be repeatedly performed, and work is performed in a state where the gap between the engagement recess 38 and the engagement pin 37 is eliminated. The lock body 30 and the engagement pin.
The life of parts such as 37 is extended.

Advantageous Effects of Invention The present invention provides a rotatable lock body as described above, and an engaging portion for locking the swing motion of the swing arm by engagement with the lock body between the rotary machine body and the swing arm. It is provided so as to be movable along the swinging direction of the swinging arm and to be fixed at an arbitrary position, and swings the swinging arm in a direction to eliminate the gap between the lock body and the engaging portion at the time of engagement. By providing the clearance elimination member on the rotary machine,
Even if a gap is generated between the lock body and the engaging portion at the time of engagement due to dimensional error during manufacturing or wear due to use, the swing arm is operated to swing the swing arm. The gap can be eliminated by
It is possible to prevent the occurrence of vibration and noise due to the existence of a gap between the lock body and the engaging portion at the time of engagement, and further to prolong the life of parts such as the lock body and the engaging portion. It has the effect of being able to.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention. FIG. 1 is a side view of the whole, FIG. 2 is an enlarged side view of essential parts, and FIG. 3 is a lock body and a spring. FIG. 4 is a plan view showing a mounted state of the stopper, FIG. 4 is a plan view showing a mounted state of the stopper, FIG. 5 is a side view showing a conventional example, and FIG. 6 is a side view showing a part of it in an enlarged manner. 18 …… Rotary body, 19 …… Tail wheel support, 22 …… Tail wheel,
23 ... Swing arm, 25 ... Plowing depth adjusting rod, 30 ... Lock body, 37 ... Engaging portion, 44 ... Gap eliminating member

Claims (1)

[Scope of utility model registration request] Claims: 1. A tail wheel support for supporting a tail wheel is vertically rotatably connected to a rotary machine body, and is vertically oscillatably connected to the rotary machine body, and the tail wheel support body. Via a plowing depth adjusting rod, and a rotatable lock body and an engaging portion for locking the swinging motion of the swing arm by engagement with the lock body are provided between the rotary machine body and the swing arm. In a tail wheel floating device of a rotary cultivator provided between the lock body and the engaging portion, the lock body and the engaging portion being movable along the swinging direction of the swinging arm and fixed at an arbitrary position. A tail wheel floating device for a rotary cultivating device, wherein a gap eliminating member for swinging the swing arm in a direction for eliminating a gap between the rotary tiller and the rotary tiller is provided.