JPH1028406A - Link mechanism for hydraulic control in working vehicle for paddy field - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a misoperation of a hydraulic device by installing regulating members, which regulate positions for raising and descending a float, in a middle link. SOLUTION: In a sulky rice planting machine, a planting unit 10 is supported to be able to ascend and descend by a hydraulic cylinder device through an ascending and descending link mechanism 8, a hydraulic control valve 35 which controls the hydraulic cylinder device 19 is connected to a float 14 through link mechanisms 42 and 41, and the hydraulic control valve 35 is controlled by upward and downward movements of the float 14 caused by changes of soil pressures given to the float 14. An upper limit-regulating member 26a and a lower limit-regulating member 26b which regulate movements of the link beyond the limits when the float 14 ascends of descends to a predetermined upper limit or lower limit are installed to a link member 22a having a pivoting support 17 on a link pole 18 among the link mechanisms 42 and 41.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control link mechanism for raising and lowering a working part such as a planting part in a paddy working vehicle such as a riding rice transplanter, and more particularly to a fluctuation of earth pressure acting on a float. The present invention relates to a link mechanism that adjusts a working unit to a fixed height with respect to a rice field surface based on the above.

[0002]

2. Description of the Related Art Generally, a riding rice transplanter has an elevation control lever which can be operated to a manual operation position and an automatic position.
While controlling the raising and lowering of the planting part by manual operation of the lever,
At the automatic position of the lever, the earth pressure acting on the float of the planting portion is sensed, and the planting portion is automatically raised and lowered by hydraulic pressure so as to be at the proper planting position.

[0003] As such a hydraulic control link mechanism,
Conventionally, for example, a mechanism as shown in FIG. 5 has been used.
That is, a sensing plate 62 is pivotally supported by a connecting pin 62a at the front of the float 14, and an elongated hole 62b is formed at an upper middle portion of the sensing plate 62.
The pin 72 fixed to the Bowden wire 71 is fitted into the b. A triangular fulcrum frame 74 is supported by a pin 74a on a bracket 73 fixed to the lower end of the link support frame 55, and a connecting rod 65 extending from the rear part of the float is connected to one corner of the fulcrum frame 74. Swing arms 75a and 75b fixed to a pivot 75 are integrally connected to the other corners.

Further, the pin 72 is fixed to the tip of one swing arm 75a, and a sensing rod 39 is connected to the tip of the other swing arm 75b. Connected to the valve. The wire connection pin 72 and the float connection pin 62
A spring 76 is stretched between "a" and "a" to position the length between the wire connecting pin 72 and the float connecting pin 62a.

[0005] When earth pressure acts on the float 14 and the front part thereof is lifted, the hydraulic control valve is moved to the automatic raising position via the sensing plate 62 and the link mechanisms 75a, 75b and 39, and the lifting link is moved. Planting part 10 by mechanism 8
On the contrary, when the earth pressure acting on the float 14 is small and its front part is lowered, the hydraulic control valve moves to the automatic lowering position and lowers the planting part 10. Thus, the hydraulic control valve is automatically controlled based on the earth pressure acting on the float 14.

However, if the float 14 moves up and down significantly, the opening of the valve also increases, causing hunting (pitting) of the planting portion 10. Therefore, conventionally, the distance between the transmission case 61 of the planting portion 10 and the float 14 is increased. The pantograph 60 provided on the hydraulic control valve mechanically regulates the lowering position of the float 14, or the extension of the spring on the hydraulic control valve side regulates the raising position of the float 14.

[0007]

However, it is difficult for the above-described conventional position raising or lowering position restricting means by the link mechanism to correctly restrict the position due to backlash between the intermediate link connecting the float 14 and the hydraulic control valve. there were. Further, in the conventional raising position regulating means, since the raising position is regulated on the hydraulic control valve side, all the play from the float 14 to the hydraulic control valve via the intermediate link is transmitted to the hydraulic control valve as a signal. And
There was a risk of malfunction.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to regulate an intermediate link connecting a hydraulic control valve and a float to regulate an up position and a down position of the float. By providing members,
An object of the present invention is to provide a hydraulic control link mechanism in a paddy field working vehicle that can prevent a malfunction of a hydraulic device.

[0009]

In order to achieve the above object, the present invention provides a traveling machine (5) in which a working unit (10) having a float (14) is connected to a hydraulic cylinder via a lifting link mechanism (8). The device (19) supports the lifting and lowering,
A hydraulic control valve (35) for controlling the hydraulic cylinder device (19) is provided, and the hydraulic control valve (35) is
Are connected to the float (14) through link mechanisms (42, 41,...), And the float (14) is moved up and down based on a change in the earth pressure acting on the float (14), so that the hydraulic control valve ( 35), the link mechanism (42, 41,...)
During the movement of the float (14), when the float (14) rises by a predetermined amount, an up-regulation member (26a) that regulates the subsequent link movement, and when the float (14) descends by a predetermined amount, a down-regulation member (26b) that regulates the subsequent link movement. ) Is provided.

Preferably, the hydraulic control valve (35)
There are a manual control range directly operated by the operation lever and an automatic control range automatically controlled by the vertical movement of the float (14).
6a) and the lowering control member (26b) are provided within the automatic control range of the hydraulic control valve (35). (Operation) Based on the above-mentioned invention specifying matter, according to the present invention, when the elevation control lever is at the automatic position, the hydraulic control valve (35) is automatically controlled based on the earth pressure acting on the float (14). For example, when earth pressure acts on the float (14) and the front part is lifted, the sensing plate (62) and the swing arms (75a, 75b), the sensing member (39), the link members (22a, 22b), The hydraulic control valve (35) is moved to the automatic raising position via the arm (41) and the continuous traction link (42) to raise the working unit (10). Conversely, when the earth pressure acting on the float (14) is small and its front part falls, the control valve (35) moves to the automatic lowering position and lowers the working part (10).

The link mechanism (42, 41,...)
The link member 22a in ()) has a float (14).
Is provided with an up-regulating member (26a) and a down-regulating member (26b) for restricting the subsequent link movement when it moves up or down to a predetermined upper limit position or lower limit position, and by these restricting members (26a, 26b), Unnecessary signals from the float (14) are cut off to prevent malfunction of the hydraulic device.

Note that the reference numerals in parentheses described above are shown for reference to the drawings, and do not limit the configuration of the present invention at all.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. Note that members that are the same as or correspond to those of the above-described conventional example are denoted by the same reference numerals and described.

As shown in FIG. 1, the riding rice transplanter 1 has a traveling body 5 supported by a front wheel 2 and a rear wheel 3, and the traveling body 5 has an engine 6 in front of the front wheel.
And a driver's seat 9 is disposed so that the seat 7 is located at an intermediate portion between the front and rear wheels, that is, at a center of gravity of the machine. Further, a lifting link mechanism 8 is provided behind the traveling body 5.
The planting unit 10 is supported so as to be able to move up and down freely through the plant. The planting unit 10 is provided with a large number of planters 11,... ing.

A hydraulic cylinder device 19 is disposed between the front transmission case 16 and the lifting link mechanism 8 in the traveling machine body 5. The hydraulic cylinder device 19 is planted based on the expansion and contraction of the hydraulic cylinder device 19 by the hydraulic control valve 35. The attachment 10 moves up and down.

That is, as shown in FIGS. 1 and 2,
A hydraulic control valve 35 composed of a rotary pool valve is installed on the seat column 25 below the driver's seat 9.
A plate 36 having a long hole 36a is fixed to a shaft 35a integral with the spool. An arm 37 is rotatably supported on the shaft 35a.
Extend so as to penetrate the long hole 36a and come into contact with the arm 37.

The arm 37 is provided with link mechanisms 42, 4
The hydraulic control valve 35 is controlled by vertical movement of the float 14 based on a change in the earth pressure acting on the float 14,
The hydraulic cylinder device 19 expands and contracts.

The link mechanisms 42, 41,... Are connected to the arm 37 on the hydraulic control valve 35 side by a continuous traction link 42, are connected to the continuous traction link 42 by pins 46, and swing to the frame 40. An arm 41 movably mounted on a shaft (44), and the arm 41 is connected to the arm 41 by a pin 41a, and can swing integrally about a pivot 17 of the link support 18 and the lower link 8b below the driver's seat 9. Link member 2
2b, 22a and a sensing member 39 connected via a pin 47 provided on the link member 22b, 22a. It is connected to the sensing plate 62 via moving arms 75a and 75b.

According to the present invention, the link mechanisms 42, 41,.
································· In に 上 げ 上 げ 上 げ 上 げ 上 げ 上 げ 上 げ 上 げ, 中 中 中 中 中 中 中 中 中. .

That is, the link mechanisms 42, 41,.
The link member 22a swingable about the pivot 17 of the lower link 8b has a large hole 2 at the center.
4 forms a frame body, and has the pivot 17 and the pin 47 at positions substantially symmetrical with respect to the hole 24. The link member 22b integrally formed with the link member 22a has an arm shape having the pivotal support 17 at one end and an elongated hole 20 formed at the other end.

A fixed link 27 is inserted through the large hole 24 of the link member 22a.
At an appropriate position around a, an up-regulation member 26a that regulates the up position of the float 14 and a down regulation member 26b that regulates the down position are attached. In the present embodiment, each of these restricting members 26a and 26b is composed of a bolt and a nut that can be adjusted in and out. Note that the link member 22b and the arm 41 are
Are connected via the long hole 20 by a pin 41a attached to the second member.

As shown in FIG. 2, the sensing plate 62 has a lower end pivotally connected to the float 14 by a connecting pin 62a, and has an elongated hole 62b formed near the upper end thereof. A Bowden wire 71 is fixed to an upper end portion of the sensing plate 62, and a pin 72 fixed to an inner 71b of the wire 71 is fitted in the long hole 62b.

Further, as shown in FIG. 4, the sensing member 39 has, at one end, a hole 28 to be fitted into the pin 47 of the link member 22a, and at the other end a long hole 29, and the pin 3 at the middle.
And a plate 39b in which a pin 31 is implanted at one end and a pin 32 which is connected to the swing arm 75b is implanted at the other end. , 31 is provided with a spring 33 stretched.

The spring 33 is provided closer to the float 14 than the lifting regulating member 26a.
In the event that there is a push-up, the spring 33 relieves the push-up so as to escape, and serves to prevent breakage of the float 14. The regulating members 26a, 2
6b protects the hydraulic control valve 35,
The link mechanisms 42, 41,... Are all raised in the direction in which a tensile load is applied, thereby ensuring good operation.

Next, the link 43 has a pin 43 implanted at an intermediate portion thereof.
A spring 45 is stretched between itself and the zero side, and the spring 45 constantly urges the continuous traction link 42 in the lowering direction of the float 14.

As shown in FIG. 1, the planting section 10 is supported by a rolling shaft (not shown) installed on a link support frame 55 at the rear end of the lifting link mechanism 8 so as to freely roll in the left-right direction. ing. The float 14 in the planting section 10 has a center part at the center thereof, and a pantograph mechanism 60.
Is vertically supported by the transmission case 61 via
Further, the sensing plate 62 is pivotally connected to a front portion of the float 14.

The swing arms 75a and 75b are
The arm comprises a bifurcated arm that can swing integrally about a pivot point 75. The swing arms 75a, 75b connect the left and right lower links 8b, 8b at the rear of the lifting link mechanism 8. Connecting plates 23, 2 mounted on horizontal shaft 21
3, it is arranged close to the horizontal axis 21. For this reason, even if the planting part 10 moves up and down, the rotation fulcrum 75 as the oil pressure sensing point does not shift, and the vertical movement of the float 14 based on the fluctuation of the earth pressure acting on the float 14 is sensed as it is.

A plate 64, a fitting 63, a connecting rod 65, and a rod arm 66 are attached to a bracket 75c connected to the rear portions of the swing arms 75a, 75b. It is connected to an adjustment lever 68.

The sensing plate 62 and the swing arm 75a
Is connected via the pin 72 fitted into the long hole 62b of the sensing plate 62, and the pin 72 and the pivot 75 are connected to the lower links 8b, 8b. They are arranged at substantially symmetrical positions with respect to the horizontal axis 21. For this reason, the swing arm 75a is formed in an arc shape so as not to abut on the horizontal shaft 21.

The tip of the swing arm 75b is provided with a pin 3
2, the sensing member 39 is connected to the wire connecting pin 72. On the other hand, a spring 76 is stretched between the wire connecting pin 72 and the float connecting pin 62a. The working length of the sensing plate 62, which is the length between the float connecting pin 72 and the float connection pin 62a, is set.

In the above, the control of the hydraulic control valve 35 includes a manual control range directly operated by the operation lever and an automatic control range automatically controlled by the vertical movement of the float 14. The up-and-down regulating member 26a and the down-regulating member 26b are provided within an automatic control range of the hydraulic control valve 35.

As shown in FIG. 2, the control of the hydraulic control valve 35 includes a manual control range which is directly operated to an up position, a fixed position, a lowered position, etc. by operating an elevation control lever (not shown), and a vertical movement of the float 14. There is an automatic control range that is automatically controlled to the raising position, the underlap position, and the lowering position, but in the present embodiment, the raising restriction member 26a and the lowering restriction member 26b are provided within the automatic control range. .

That is, when there is no regulating member during automatic control by hydraulic pressure, if the float 14 is moved to the upper limit position or the lower limit position, the hydraulic oil is suddenly supplied to the hydraulic cylinder device 19 in conjunction with the movement. Since the pressure oil is fed or the pressure oil is rapidly discharged from the hydraulic cylinder device 19, the cylinder speed is increased, and there is a possibility that a malfunction such as hunting may occur in the operation of the hydraulic device. However, in the present embodiment, the lifting control member 26 is attached to the link member 22a.
By providing the lowering member 26a and the lowering restricting member 26b, the flow path of the pressure oil is narrowed to reduce the cylinder speed, thereby preventing malfunction of the hydraulic device.

Next, the operation of the above-described embodiment will be described.

When the lifting control lever is operated to the automatic position,
Based on the earth pressure acting on the float 14, the swing arm 75
The hydraulic control valve 35 is controlled by the continuous traction link 42 via a and 75b. That is, when the planting section 10 is at the proper planting position, the control plate 36 is at the fixed position via the arm 37 and the pin 32, and the hydraulic control valve 35 is held to hold the planting section 10 at that position. I do.

In this state, when the planting section 10 rises with respect to the rice field surface and the earth pressure acting on the float 14 decreases, the front of the float 14 decreases, and the movement is detected by the sensing plate 62.
And the pin 7 positioned at a predetermined position of the long hole 62b
The rotation is transmitted to the swing arm 75 a through the rotation arm 2 in the counterclockwise direction (FIG. 2), and the swing arm 75 b also rotates in the same direction via the rotation fulcrum 75 to press the sensing member 39.

At this time, the pressing force rotates the link members 22a and 22b counterclockwise about the pivotal support portion 17, and accordingly rotates the arm 41 clockwise about the fulcrum 44. 42 is moved clockwise about the fulcrum 44. The movement of the link 42 is achieved by rotating the arm 37 clockwise about the axis 35a, and furthermore, since the pin 32 is in contact with the arm 37, the control plate 36 is integrated with the arm 37 via the pin 32. Is turned to the lowered position, and the hydraulic control valve 35 is
Switching to discharge the oil in the hydraulic cylinder device 19,
The planting section 10 is lowered by contracting the cylinder device.

Conversely, when the planting portion 10 descends and the earth pressure acting on the float 14 increases, the front of the float 14 rises, and the movement is detected by the sensing plate 62 and the swing arm 7.
5a, 75b, sensing member 39, link members 22a, 22
b and the traction link 42 via the arm 41 to the fulcrum 44
, The arm 37 is rotated counterclockwise, and the control plate 36 is integrated with the arm 37.
Is turned to the raised position. As a result, the hydraulic control valve 35 is switched to pressurize the hydraulic oil to the hydraulic cylinder device 19, and the rod of the cylinder device 19 is extended to raise the planting section 10 to an appropriate position.

In the above, since the link member 22a is provided with the regulating members 26a and 26b for regulating the raised position and the lowered position of the float 14, the float 1
4 moves to the upper limit position or the lower limit position, whereby the regulating members 26a, 26b come into contact with the fixed link 27,
The transmission of the signal from the float 14 after the contact to the hydraulic control valve 35 is cut off, and unnecessarily erroneous operation is prevented, and the pressure oil flow path in the automatic control range is restricted by the regulating members 26a and 26b. As a result, the operation of the cylinder and the like is delayed, and hunting of the planting portion 10 is prevented.

[0040]

As described above, according to the present invention,
On the traveling machine body, while supporting a working unit having a float by a hydraulic cylinder device via a lifting link mechanism,
A hydraulic control valve for controlling the hydraulic cylinder device is provided, and the hydraulic control valve is further connected to the float via a link mechanism, and the float is moved up and down based on an earth pressure fluctuation acting on the float. In a paddy field vehicle controlled by a hydraulic control valve, in the link mechanism, an up-regulating member that regulates a subsequent link movement when the float rises a predetermined amount, and regulates a subsequent link movement when the float descends a predetermined amount. With the provision of the lowering restriction member, a signal exceeding the restriction value from the float is cut off in the link mechanism, so that unnecessary malfunction by the hydraulic device can be prevented.

Further, as described above, since the signal from the float equal to or higher than the regulation value is cut off in the link mechanism, the operation of the hydraulic control valve can be stabilized. Furthermore, since the dead zone amount including the backlash from the float to the hydraulic control valve can be absorbed by the link mechanism, hunting of the hydraulic device can be prevented.

Further, in the present invention, as the control of the hydraulic control valve, there are a manual control range directly operated by an operation lever and an automatic control range automatically controlled by vertical movement of the float. By providing the regulating member and the lowering regulating member within the automatic control range of the hydraulic control valve, it is possible to restrict the flow path of the pressure oil, slow down the operation of the hydraulic device, and prevent hydraulic hunting during planting. In addition, the planting performance can be improved. On the other hand, in the manual range, since the hydraulic control valve is directly operated, the operation of the hydraulic device is fast, and there is no problem such as circling. Further, although the body descends when the hydraulic lever is turned off, the flow path of the pressure oil is narrowed thereafter, so that the hydraulic hunting can be prevented.

[Brief description of the drawings]

FIG. 1 is a side view of a riding rice transplanter to which the present invention is applied.

FIG. 2 is a diagram showing an overall configuration of a hydraulic control link mechanism according to the present invention.

FIG. 3 is a plan view of FIG. 2;

FIG. 4 is an exploded perspective view of FIG. 2;

FIG. 5 is a side view of a float portion of a conventional hydraulic control link mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Riding rice transplanter 5 Traveling body 8 Elevating link mechanism 8a Lower link 10 Implantation part 14 Float 17 Pivot support part 19 Hydraulic cylinder device 21 Horizontal axis 22a, 22b Link member 23 Connection plate 26a Lifting regulating member 26b Lowering regulating member 35 Hydraulic control valve 39 sensing member 40 frame 41 arm 42 continuous traction link 55 link support frame 62 sensing plate 75a, 75b swing arm

Claims (2)

[Claims] An operating unit having a float is vertically supported by a hydraulic cylinder device via a lifting link mechanism on a traveling machine body, and a hydraulic control valve for controlling the hydraulic cylinder device is provided, and the hydraulic control valve is further provided. Is connected to the float via a link mechanism, and the hydraulic control valve is controlled by vertical movement of the float based on fluctuations in earth pressure acting on the float. For raising hydraulic pressure in a paddy working vehicle, comprising an up-regulating member that regulates subsequent link movement when the float rises by a predetermined amount, and a lowering regulating member that regulates subsequent link movement when the float descends by a predetermined amount. Link mechanism. 2. The control of the hydraulic control valve includes a manual control range directly operated by an operation lever and an automatic control range automatically controlled by vertical movement of a float. The link mechanism for hydraulic control in a paddy working vehicle according to claim 1, wherein a regulating member is provided within an automatic control range of the hydraulic control valve.