JPS6125605Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an operating lever guide for an agricultural tractor, and in particular to a guide for a position control lever and a depth control lever.

Conventionally, guides for hydraulic operating levers that require operation guides for position control and the like have been attached to a hydraulic case or the like and provided between the rear wheel fender and the seat or below the seat.
For this reason, it is located considerably below the driver's field of vision, making it difficult to confirm the position of the operating lever with respect to the guide, which is often inconvenient for detailed work. Furthermore, in these models, the seat portion is narrow, and driving comfort is compromised.

Therefore, the present invention provides an operating lever guide for an agricultural tractor that eliminates the above-mentioned drawbacks by configuring the operating lever to be guided by a guide arranged on the top surface of the fender so as to roughly follow the outer shape of the fender. The purpose is to

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

As shown in FIG. 1, the agricultural tractor 1 has a body 5 supported by front wheels 2 and rear wheels 3, and an engine 6 is mounted on the front of the body 5.
A driver's seat 7 is arranged from the middle to the rear. Further, a hydraulic case 8 containing a hydraulic operating mechanism including a piston, a cylinder, etc. is arranged at the rear of the body 5, and a lift arm 10 is rotatably provided in the case 8. Further, behind the machine body 5, a working machine 12 having a rotary blade 11 is pulled by a hitch pin 13 and connected to a lift arm 10 via a lift rod 15. The driver's seat 7 has a handle 16 and a seat 17,
Further, the position control lever 18 and the depth control lever 20 are arranged adjacent to each other so as to be able to rotate coaxially. Each lever 18, 20 has a grip 18a, 20a on its head, as shown in FIGS. It is guided by guide grooves 22a and 22b of a guide 22 arranged along the guide. Specifically, as shown in FIG. 4, the rear upper surface of the fender 21 is formed by a substantially horizontal surface 21a, and the front portion thereof is formed by an inclined surface 21b. A box-shaped guide 22 having a predetermined length is fixed to the upper surface of the fender 21 with bolts 24, sandwiching the bent portion 21c between the horizontal surface 21a and the inclined surface 21b. In the guide grooves 22a and 22b of the guide 22, the position control lever 18 and the depth control lever 20, which extend between the seat 17 and the vertical wall of the fender 21, are bent and guided. Further, a display board 23 is provided at an intermediate portion between the guide grooves 2a, 22b of the guide 22, and instructions for each lever 18, 20 are displayed on the display board 23, as shown in FIG. The position control lever 18 is
As shown in FIG. 5, the disc spring 25 is attached to the hydraulic case 8.
and is fixed to a support shaft 27 which is rotatably supported by a friction force applied by a nut 26,
The support shaft 27 includes an arm 28, a link 30, and an arm 31.
It is interlocked with the valve shifter 32 via the interlocking shaft 31 and the interlocking shaft 31. Valve shifter 32 has pin 3 in the center.
It is connected via a pin 32a to the upper end of a valve link 34 which is pivotally supported by pin 3b.
3b is connected to the spool 33a of the hydraulic control valve 33. Further, as shown in FIG. 4, a fat control link 35 is pivotally supported on the position control lever 18 by a pin 18b.
is connected to the intermediate portion of a feedback shifter arm 37 fixed to a support shaft 36 via a transmission link 38. The tip of the shifter arm 37 is connected to the position feed back link 40 at the stopper portion 4.
The link 40 is further connected to the lift arm 10 via a joint 42 by a pin 10a. Further, the feedback shifter arm 37 is connected to a valve shifter 43 via a support shaft 36, and the shifter 43 is connected to the lower end of the valve link 34 by a pin 43a. In addition, in the middle part of the depth control link 35, as shown in FIGS. 4 and 7, there is a connecting pin 4 extending upward.
5 is provided. On the other hand, as shown in FIGS. 4, 5, and 8, the depth control lever 20 is rotatably supported on a support shaft 27, and its elongated hole 20b is connected to a pin provided in the hydraulic case 8. 46 and is fitted with friction by a disc spring 47 and a nut 48. Further, a joining link 50 is provided on the lever 20 by a pin 20c. The joining link 50 has a bent portion 50a as shown in FIG.
It is arranged so that it can be selected to be connected to the connecting pin 45 provided on the depth control link 35 or not depending on the position of c. Also,
The other end of the joining link 50 is connected to a push link 51 by being clamped by a spring 52 and a nut 51a, and further includes a sensor responsive link 55 and a Bowden wire 5 which are pivotally supported by a bracket 53.
6. It is connected via a bell crank 57 and a link 58 to a rear cover 60 (see FIG. 1) of the working machine 12, which constitutes a height above the ground sensor.

With the above configuration, the position control lever 18 can be moved into the guide groove 2 of the guide 22.
2a in the downward direction while looking at the display on the display board 23, the support shaft 27 and the arm 2
8. Rotate the valve shifter 32 counterclockwise via the link 30, arm 31a, and interlocking shaft 31. This allows the valve link 34 to connect to the pin 4 at the lower end.
3a as a fulcrum, and connects the spool 3 of the hydraulic control valve 33 via a central pivot pin 33b.
3a in the direction of arrow B in FIG. Therefore, the hydraulic oil is discharged from the cylinder in the hydraulic case 8,
The lift arm 10 rotates counterclockwise, and the work implement 12 descends due to its own weight. This rotation of the lift arm 10 causes the pin 10a and the joint 4 to
2. The feedback shifter arm 37 rotates clockwise about the support shaft 36 via the position feedback link 40, and further rotates the valve shifter 43 in the same direction via the support shaft 36. As a result, the valve link 34 rotates clockwise about the pin 32a at the upper end as a fulcrum, and moves the pin 33b in the direction of arrow A by the amount of movement described above. Therefore, the sprue 33a of the hydraulic control valve 33 is moved, the valve 33 is in a neutral position, and the lift arm 10, that is, the work implement 12 is held at a position corresponding to the movement position of the position control lever.
On the other hand, the position control lever 18
When the lever 18 is rotated to the upward side, the work implement 12 moves to the lever 18.
is held in a raised position corresponding to

Next, depth control will be explained.
First, move the depth control lever 20 to guide 2.
2 along the guide groove 22b and the display plate 2
It is held in a predetermined position by adjusting the display as shown in step 3 as appropriate. From this state, when the position control lever 18 is rotated in the downward direction, the work equipment 1
2 descends as described above, the rotary blade 11 starts tilling, and the rear cover 60 comes down to the ground. When the work equipment 12 is further lowered, the rear cover 60 rotates upward relative to the work equipment 12 due to ground pressure, and this rotation is caused by the link 58, the bell crank 57,
Bowden wire 56, sensor responsive link 55,
The force is transmitted to the joining link 50 via the bushing link 51, and the link 50 is rotated counterclockwise around the pin 20c. When the plowing depth of the work implement 12 reaches a predetermined depth determined by the depth control lever 17, the joint link 50 is simultaneously joined to the joint pin 45 provided on the depth control link 35. That is, the position of this position control lever 18 corresponds to the plowing depth under normal conditions by depth control. When the position control lever 18 is further rotated in the downward direction, the valve shifter 32 is rotated counterclockwise via the support shaft 27, arm 28, link 30, arm 31a, and interlocking shaft 31 in the same manner as described above, and Valve link 34
Rotate the upper end of the pin in the direction of arrow B, but at the same time
8b, the depth control link 35 connects to the joining pin 45.
This rotation causes the feedback shifter arm 37 to rotate clockwise through the transmission link 38 while compressing the spring 41 about the support shaft 36. As a result, the valve shifter 43 also rotates in the same direction via the support shaft 36, and the lower end of the valve link 34 is rotated in the direction of arrow A by the amount considered to be the movement of the upper end by the pin 43a. Therefore, the spool 33a does not move and the hydraulic control valve 33 is still maintained at the neutral position. That is, the position control lever 18
is at a position where the working implement 12 is higher than the plowing depth position determined by the depth control lever 20, position control takes priority over depth control, and conversely, the position control lever 18 is set by the depth control lever 20. When the work implement 12 is at a lower plowing position than the plowing depth position, depth control has priority over position control. Therefore, in actual work, when depth control is used, the position control lever 18 is rotated almost fully in the downward direction. At this time, the adjustment of the plowing depth position using the depth control is based on the amount of rotation of the depth control lever 20, that is, the amount of rotation of the pin 20.
The joining position with the joining pin 45 when the joining link 50 is rotated via the Bowden wire 56, the sensor response link 55, and the bushing link 51 based on the rotation of the rear cover 60. This is done by adjusting the now,
When the truck 1 reaches soft ground or the like and the machine body 5 and work equipment sink, the rear cover 60 rises due to ground pressure. This upward movement rotates the joining link 50 counterclockwise about the pin 20c via the Bowden wire 56 and the like. As a result, the depth control link 35 is rotated counterclockwise by the connecting pin 45 using the pin 18b as a fulcrum, and the feedback shifter arm 37 is further rotated clockwise against the spring 41 via the transmission link 38. The pin 43a of the valve shifter 43 rotates the valve link 34 in the same direction about the pin 32a at its upper end as a fulcrum. Therefore, the spool 33a of the hydraulic control valve 33 moves in the direction of arrow A via the pin 33b, and the work implement 12 rises due to the rotation of the lift arm 10. When the work equipment 12 rises to a predetermined height above the ground,
The ground pressure of the rear cover 60 is removed, and the joining link 50 rotates clockwise, contrary to the above. As a result, a gap is created between the connecting pin 45 and the connecting link 50, and the compressed spring 41 causes the feedback shifter arm 37 to rotate counterclockwise, thereby moving the support shaft 36, valve shifter 43, and pin 43a. Connect the valve link 34 to the pin 32a through
The hydraulic control valve 33 is rotated counterclockwise about the fulcrum, thereby moving the spool 33a in the direction of arrow B, and the hydraulic control valve 33 is held at the neutral position again.

Furthermore, when the depth control lever 20 is fully rotated toward the plow depth side and rotated to the depth release position, the bent portion 50a of the joining link 50 also moves upward as the pin 20c rotates upward. In this state, even if the position control lever 18 is fully rotated in the downward direction, the depth control link 35 is continuously pulled by the pin 18b, and the joint body 45 is brought close to the full position, the joint link 50 will not move at its bent portion 50a. is located above, so there is no joining. As a result, the linkage relationship between the joining link 50 and the depth control link 35 is released, and the depth control is released.

As explained above, according to the present invention, the guides 22 for the operating levers 18 and 20 are provided on the top surface of the fender 21, so they can be easily seen and detailed operations can be performed easily and safely. can. Moreover, since the guide 22 functions as an armrest when operating the lever, the user can operate the lever accurately without getting tired even during long hours of work. Further, since the upper surface of the guide 22 along the rotation of the operating levers 18 and 20 is arranged so as to roughly follow the outer shape of the fender 21, the appearance is also excellent. Furthermore, since the operating levers 18, 20 and the guide 22 are provided on the fender 21 outside the driver's seat 7, the tractor 17 can be made wider and the driving comfort is improved, and there is also sufficient space for the guide 22. A large display board 23 with
This can prevent malfunction of the lever. In addition, although the fender 21 has a simple structure with a substantially linear shape, with the rear upper surface being a substantially horizontal plane 21a and the front part being inclined 21b, the guide 22 is Since the operating levers 18 and 20 are installed at a predetermined length position sandwiching the bent portion 21c formed by the horizontal surface 21a and the inclined surface 21b on the upper surface of the fender 21, the arc of the operating levers 18 and 20 swings about the support shaft 27. The upper surface of the guide 22, that is, the guide grooves 22a, 22b, and the display plate 23 can be easily brought close to and aligned with the trajectory, and the tractor 1
Coupled with the arrangement of the guide 22 located in a wide area on the 7 sides, the lever operation can be performed extremely easily and accurately. Furthermore, since the guide 22 has a box shape and is fixed to the top surface of the fender 21, the guide 22 has an extremely robust structure.
Although the operating levers 18 and 20 are bent and extend between the vertical wall of the fender 21 and the tractor 17 and have a weak structure that is easily bent, the operating levers can be reliably guided to ensure accurate operation. In addition, the strength of the entire operation lever device including the guide 22 can be increased. In particular, when used for the position control lever 18 and the depth control lever 20 that are arranged adjacent to each other and can rotate coaxially, there is no need to turn back to check the height of the work implement 12, and both levers 18 and 20 can be operated in conjunction with each other, so there is no erroneous operation and the operation can be performed safely.

[Brief explanation of the drawing]

Fig. 1 is a side view showing an agricultural tractor according to the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a rear view, and Fig. 4 is a side view showing an agricultural tractor according to the present invention.
The figure is a side view showing the position control lever and the depth control lever, FIG. 5 is a front sectional view thereof, FIG. 6 is a plan view showing the guide, FIG. 7 is a partial front sectional view of each lever, and FIG. FIG. 3 is a sectional view showing the attachment portion of each lever. DESCRIPTION OF SYMBOLS 1... Agricultural tractor, 3... Rear wheel, 7... Driver's seat, 18... Operating lever (position control lever), 20... Operating lever (depth control lever), 21... Fender, 21a...
... horizontal surface, 21b ... slope, 21c ... bending part, 22 ... guide, 22a, 22b ... guide groove, 23 ... display board.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) An agricultural tractor having a rear wheel fender on the side of the operating lever and the driver's seat, wherein the rear upper surface of the fender is substantially horizontal and the front thereof is an inclined surface. Furthermore, a box-shaped guide of a predetermined length is fixed to the upper surface of the fender, sandwiching the bent part between the horizontal surface and the inclined surface, and the guide has a guide groove and a display plate on its upper surface. and the operating lever,
An operating lever guide for an agricultural tractor that bends and extends from between a driver's seat and a fender and is guided into the guide groove. (2) The operating lever guide according to claim 1, wherein the operating levers are a position control lever and a depth control lever that are arranged adjacent to each other and can rotate coaxially.