JPH09327206A - Device for controlling elevation of working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for controlling the elevation of a working machine, enabling to easily attach a linkage part for linking a position control mechanism to a tilling depth control mechanism from the outside, capable of corresponding to both a pulled working machine and a non-pulled working machine, and capable of controlling the movement quantity of a movement quantity-transmitting mechanism to protect a hydraulic part. SOLUTION: A support metal fitting 28 is fixed to a member for fixing a top link bracket to a machine frame, and a sensitive lever plate 29 is rotatably attached to the side surface of the support metal fitting 28. A device for controlling the rotation quantity of the sensitive lever plate 29 is attached to the support metal fitting 28. Points for linking the sensitive level plate 29 to a linkage mechanism are disposed at both upper and lower places in the front of the rotation support point of the sensitive lever plate 29, and the linkage mechanism is selectively attached to either one of the linking points. Thereby, the linkage mechanism can be corresponded in a constant direction of pulling or pressing in both cases that the sensitive lever plate 29 is rotated in the normal direction or in the reverse direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an agricultural tractor capable of controlling a working machine with position control and automatic depth control such as depth control or resistance control, and more particularly, a connection between a position control mechanism and a depth control mechanism. Regarding the mechanism.

[0002]

2. Description of the Related Art As is known from Japanese Utility Model Publication No. 48-21771, Japanese Utility Model Publication No. 5512650, Japanese Patent Publication No. 51562 and Japanese Patent Publication No. 55801, position control and plowing are performed with a single operating lever as a reference. A working machine lifting control device for performing automatic plowing depth control such as depth control or resistance control is already known.

[0003]

The already known ones disclosed in Japanese Utility Model Publication No. 5512650 and Japanese Patent Publication No. 51562 are capable of responding to position control and plowing depth control or resistance control alone. The present invention was devised and invented so that it can respond to position control, plowing depth control and resistance control by a single operating lever.
Even those disclosed in Japanese Patent Laid-Open No. 8-21771 and Japanese Patent Publication No. 55801/1998 have a difficulty in switching work because they require replacement of parts inside the hydraulic case or large parts replacement outside.

Further, since the moving amount of the second moving amount transmitting mechanism from the working machine is not restricted, there is a possibility that the interlocking first moving amount transmitting mechanism may be damaged.

Therefore, according to the present invention, a supporting metal fitting is attached to the rear portion of the machine body so that the connecting mechanism portion of the first movement amount transmission mechanism and the second movement amount transmission mechanism can be easily attached from the outside.
The amount of movement of the second movement amount transmission mechanism is regulated to ensure safety,
Further, by providing two fulcrums on the sensing lever plate rotatably supported by the support fitting and selectively attaching the connecting mechanism to either one, position control, working depth control and resistance control can be performed by one operating lever. The purpose is to make it responsive and to facilitate switching work.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a working machine (1) is provided via a top link bracket (13) fixed to the rear part of the machine body (3).
6) and (32) are mounted so that they can be moved up and down, and a hydraulic control valve (7)
The operation lever (11) and the lift arm (1
0) is continuously swung via the first movement amount transmission mechanism, and the position control mechanism for operating the lift arm (10) to a position corresponding to the position of the operation lever (11), and the working machine (1).
6) and (32) are connected through a connecting mechanism (38) with a working depth control mechanism that senses the working depth during work and controls the hydraulic control valve (7) through the second movement amount transmission mechanism. In the automatic plowing depth control device for the agricultural tractor (1), the support metal fitting (28) of the second movement amount transmission mechanism is fixed to the fixing portion of the top link bracket (13) to the machine body (3). ,
A sensing lever plate (29) rotatably supported on the side surface of the support fitting (28) is mounted, and the support fitting (28)
A rotation amount restricting device (29b) for the sensing lever plate (29) is provided on the sensing lever plate (29), and a joint point between the sensing lever plate (29) and the connecting mechanism (38) is a fulcrum of the sensing lever plate (29). The connection mechanism (3
8) is selectively attached to either one of the joining points (29d) and (29e), the connecting mechanism (38) pulls or compresses regardless of whether the sensing lever plate (29) rotates in the forward or reverse direction. The above-mentioned problem was solved by arranging so as to be able to respond in a fixed direction.

(Operation) Based on the above structure, the rotary (1
When cultivating at 6), one end of the connecting mechanism (38) is connected to one fulcrum (29d) of the sensing lever plate (29), and the automatic tilling depth control lever (37) is set at a predetermined position. When the plowing work is carried out with a depth of more than the predetermined plowing depth h, the sensing lever plate (29) rotates clockwise and pushes the connecting mechanism (38) to cause the hydraulic control valve 7 to act in the direction to make the plowing depth shallow. The working depth h can be maintained.

When plowing with the plow 32,
One end of the connecting mechanism (38) is connected to the other fulcrum (29e) of the sensing lever plate (29), and when it becomes deeper than a predetermined plowing depth h ', the sensing lever plate (29) rotates counterclockwise and connects. When the mechanism (38) is pushed, the hydraulic control valve (7) acts in the direction to make the working depth shallow, and the predetermined working depth h'can be maintained.

Regardless of rotary tillage work or plow tillage work, a predetermined tillage depth h. When it becomes shallower than h ′, contrary to the above, the hydraulic control valve (7) acts to automatically control the working depth so that the predetermined working depth can always be maintained.

Since the rotation angle of the sensor lever plate (29) during the operation of the automatic plowing depth control is regulated by coming into contact with the regulation portion of the support fitting (28), the internal movement amount transmission mechanism is damaged. There is no fear.

The reference numerals in parentheses above are for comparison with the drawings, but do not limit the configuration of the present invention.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the agricultural tractor 1 has a machine body 3 supported by wheels 2, and the machine body 3
An engine 5 is mounted in the front part of the vehicle and a driver's seat 6 is arranged in the rear part of the vehicle.

A hydraulic case 9 containing a hydraulic cylinder device and a hydraulic control valve 7 (FIG. 2) is disposed below the driver's seat 6. From the left and right side surfaces of the hydraulic case 9, the hydraulic cylinder device is used. The rotatable lift arm 10 projects
is set up. An operating lever 11 for raising and lowering the working machine is rotatably supported on the side of the driver's seat 6 while being prevented from being blinded by a pressure support tool, and the operating lever 11 is controlled based on the position control to control the working depth or It is possible to operate the lifting operation of the work machine by automatic depth control such as resistance control.

Further, a lower link 12 is provided behind the fuselage 3.
Also, the rotary 16 is mounted by the top link 15 via the top link blats 13 fixed to the body 3, and further, the lower link 12 of the rotary 16 is connected to the lift arm 10 via the lift rod 17. It can be raised and lowered.

The rotary 16 has a rotary blade 20 to which power is transmitted from the PTO shaft 19, and a rear portion of the rotary blade 20 is covered with a rear cover 22 pivotally supported by a rotary machine frame 21.

The rear cover 22 functions as a leveler for preventing the cultivated soil mass from scattering by the rotary blade 20, and for leveling the surface of the cultivated soil, and for detecting the height of the field in the rotary 16, that is, the depth of cultivation h. Also has the function of.

A rod 23 is pivotally supported at the tip of the rear cover 22, and the upper end of the rod 23 is slidably held by a bracket 25 which is supported on the machine frame 21 in a height-adjustable manner. In addition, it is urged downward by the spring 26.

Further, one end of a Bowden wire 27 is connected to the upper end of the rod 23, and the other end of the Bowden wire 27 is supported together with the top link blats 13 fixed to the machine body 3 and a supporting metal fitting 28. It is connected to a tip portion 30 of a sensor lever 29b of a sensing lever plate 29 which is rotatably supported.

On the other hand, as shown in FIG. 3, when, for example, the plow 32 for pulling work is attached to the rear of the machine body 3, the top link 15 is passed through the lower link 12 and the top link brat 13 fixed to the machine body 3. By plow 32
The upper part of the plow 32 is attached, and the lower part of the plow 32 is connected to the lift arm 10 via the lower link 12 and the lift rod 17 so that the plow 32 can be moved up and down.

The plow 32 main body is supported and the top link 1
One end of a Bowden wire 34 is connected to a connecting member 33 that is connected to 5, and the other end of the Bowden wire 34 is connected to a support metal fitting 28 that is fastened together with the top link brat 13 fixed to the machine body 3. It is connected to the tip portion 30 of the sensor lever 29b of the sensing lever plate 29 pivotally supported.

When plowing the field with the plow 32, the resistance of the soil is directly applied to the plowing surface and the resistance value changes in proportion to the plowing depth h '. Therefore, it is necessary to detect the depth of the plowing depth h'. Acts as a sensor.

Further, as shown in FIG. 4, the support fitting 28 uses a bolt 35 for fixing the top link brat 13 to the rear portion of the machine body 3 and is attached to the side surface of the hydraulic case 9 together with the top link brat 13 so as to face forward. A rotation fulcrum 28 that is fastened together and projects outward from the side surface of the support fitting 28.
A sensing lever plate 29, which is an essential part of the present invention, is rotatably supported on a.

The sensing lever plate 29 has a plate portion 29a which rotates along the outer surface of the support fitting 28 and a rotation fulcrum 28a.
A sensor lever 29b that rotates around the fulcrum 2 and a fulcrum 2 that protrudes outward at two front upper and lower positions of the rotation fulcrum boss 29c.
9d and 29e are integrally configured, and the fulcrums 29d and 29e form a joint point with a connecting rod 38 described later.

As shown in FIG. 5, one end of the connecting rod 38 is joined to a fulcrum 29d or 29e, the other end is connected to the sensor arm 39, and further, inside the hydraulic case 9, a first position control system is provided. The plowing depth h and plowing depth h'are detected based on the position determined by the automatic plowing depth control lever 37 connected to the movement amount transmission mechanism and connected to the sensor arm 39, and the hydraulic control valve 7 is controlled to perform automatic plowing. Performs deep control.

At this time, since a flexible mechanism is interposed between the position control operation lever 11 and the first movement amount transmission mechanism, the automatic plowing depth control lever 37 automatically controls the plowing depth. Is configured to operate in priority to the position control by the operation lever 11.

Further, as shown in FIG. 4, the sensor lever 29b is bent inward from the plate portion 29a, while the mounting surface of the support fitting 28 with the top link 15 has the same width as the mounting surface width l. Regarding the width, the lower part is formed to be wider than the mounting surface width and has an L width, and a step having a dimension of L-1 is provided in the middle portion. Further, a stopper plate 28b is fixed to the vertical surface of the rear end portion of the support metal fitting 28, and when the sensor lever 29c rotates back and forth around the rotation fulcrum 28a, the bending portion is the L-
On the front side of the step portion having the dimension l, the cross section of the plate thickness of the sensor lever 29c abuts on the stopper plate 28b to regulate the rotation angle of the sensor lever 29c.

Next, the operation of this embodiment will be described.

Based on the above structure, when cultivating with the rotary 16, one end of the connecting rod 38 is connected to the fulcrum 29d of the sensing lever plate 29, and the automatic plowing depth control lever 37.
Is set to a predetermined position to perform plowing work, and when it becomes deeper than a predetermined plowing depth h, the rear cover 22 is pushed up, the Bowden wire 27 connected thereto is pushed, and the sensor lever 2
9b is pushed up, the sensing lever plate 29 rotates clockwise, pushes the connecting rod 38, and the hydraulic control valve 7 acts in the direction of making the working depth shallow, so that the predetermined working depth h can be maintained.

When plowing with the plow 32,
One end of the connecting rod 38 is connected to the fulcrum 2 of the sensing lever plate 29.
9e, the automatic plowing depth control lever 37 is set to a predetermined position to perform plowing work, and when the plowing depth becomes deeper than a predetermined plowing depth h ', the resistance of the working surface of the plow 32 increases and the plow 32 is supported. The member 33 moves downward, the Bowden wire 34 connected thereto is pulled, the sensor lever 29b is pushed down, the sensing lever plate 29 rotates counterclockwise and the connecting rod 38 is pushed, and the hydraulic control valve 7 is cultivated. A predetermined plowing depth h ′ can be maintained by acting in the direction of decreasing the depth.

Regardless of rotary tillage work or plow tillage work, a predetermined tillage depth h. When it becomes shallower than h ', the hydraulic control valve 7 acts in the direction of deepening the working depth to control the working depth automatically contrary to the above, and it is possible to always maintain the predetermined working depth.

The rotation angle of the sensor lever 29b, which is the center of the above-mentioned automatic movement control mechanism for transmitting the amount of movement under plowing, contacts the step of the L-1 size of the support fitting 28 and the stopper 28b at the rear end of the support fitting 28. As a result, the external movement amount transmission mechanism can prevent damages to the internal movement amount transmission mechanism without causing an abnormally large movement amount.

The operation lever 11 and the automatic plowing depth control lever 37 are rotated by being guided by the same lever guide 41 provided outside the driver's seat 6, as shown in FIG. 6 (a). Since it can be operated freely, in order to prevent erroneous operation, for example, as shown in FIGS. 6B and 6C, the lever guide 4
1 is formed with a locking hole 41b in the side surface 41a, and a protrusion 37a on the plowing depth automatic control lever 37 side is fitted and locked at a predetermined position to prevent blind movement. The locking release device is operated on the automatic control lever 37 side with a fingertip so as to be rotatable, or as shown in FIG. 7A, a locking notch 41d is provided on the upper surface 41c of the lever guide 41. As a stop device, the cross section of the automatic plowing depth control lever 37 is fitted into the notch 41d to prevent blind movement, while a spring 42 as shown in FIG. 7 (b) is provided at the base of the automatic plowing depth control lever 37. The flexible portion 43 through the
When rotating 7, the flexible part 43 is resisted against the spring 42.
To release it from the notch 41d, and move the lever guide 4
It can also be moved back and forth along one guide groove.

Further, at the base of the automatic plowing depth control lever 37,
Two springs 42 as shown in FIGS. 8 (a) and 8 (b) are used together to prevent the automatic plowing depth control lever 37 from collapsing, and as shown in FIGS. 9 (a) and 9 (b). Like hinge 44
In combination with this, it is possible to prevent the automatic plowing depth control lever 37 itself from falling when unlocking from the notch 41d.

[0035]

According to the present invention, the working machine is mounted so as to be able to move up and down through the top link bracket fixed to the rear part of the machine body, and the operation lever and the lift arm are provided on the operation section of the hydraulic control valve.
A position control mechanism for continuously lifting and lowering the lift arm to a position corresponding to the position of the operation lever, and a working depth of the working machine while sensing the working depth of the working machine. In an automatic tillage depth control device for an agricultural tractor, which is joined via a connecting mechanism with a tilling depth control mechanism that controls a hydraulic control valve through a movement amount transmission mechanism, in the fixing portion to the fuselage of the top link bracket, The support metal fitting of the second movement amount transmission mechanism is fixed, a sensing lever plate rotatably supported on the side surface of the support metal fitting is mounted, and a rotation amount regulating device for the sensing lever plate is provided on the support metal fitting. , The sensing lever plate and the connecting mechanism are provided at two points above and below the rotation fulcrum of the sensing lever plate, and the connecting mechanism is selectively attached to either one of the joining points, whereby the sensing lever plate is attached. The direction of rotation is Also in this case, since the connecting mechanism is arranged so as to be able to respond to a fixed direction of tension or compression, it is possible to perform both cultivating work and towing work by selective mounting operation at a simple joint without damaging the movement amount transmission mechanism. Automatic plowing depth control is now possible.

[Brief description of drawings]

FIG. 1 is a side view during rotary tillage.

FIG. 2 is a side view of the position control device.

FIG. 3 is a side view during plowing plowing.

FIG. 4 is a perspective view of a main part control device of the present invention.

FIG. 5 is a side view of the automatic tilling depth control device.

FIG. 6A is a side view of a position control device operating lever and an automatic plowing depth control lever. (B) is sectional drawing of an automatic plow control lever erroneous operation prevention apparatus. (C) is a side view of an automatic operation control device for an automatic working depth control lever.

FIG. 7A is a top view of an automatic plowing depth control lever erroneous operation preventing device according to another embodiment. (B) is a rear view of the automatic plunge depth control lever erroneous operation preventing device according to another embodiment.

FIG. 8A is a top view of an automatic working depth control lever erroneous operation prevention device according to another embodiment. (B) is a rear view of the automatic plunge depth control lever erroneous operation preventing device according to another embodiment.

FIG. 9 (a) is a top view of an automatic working depth control lever erroneous operation prevention device according to another embodiment. (B) is a rear view of the automatic plunge depth control lever erroneous operation preventing device according to another embodiment.

[Explanation of reference numerals] 1 agricultural tractor 7 hydraulic control valve 11 lift arm 16 rotary 28 support fitting 29 sensing lever plate 32 plow 37 automatic tilling depth control lever 39 sensor arm

Claims (2)

[Claims] 1. A work machine is mounted so as to be able to move up and down via a top link bracket fixed to the rear part of the machine body, and an operation lever and a lift arm are attached to an operation section of a hydraulic control valve via a first movement amount transmission mechanism. A position control mechanism that continuously lifts and operates the lift arm to a position corresponding to the position of the operation lever, and a hydraulic control valve that senses the working depth of the working machine during work and that uses a second movement amount transmission mechanism. In the automatic tilling depth control device for an agricultural tractor, which is joined with a tilling depth control mechanism for controlling the above through a connecting mechanism, a support fitting for the second movement amount transmitting mechanism is provided at a fixing portion of the top link bracket to the machine body. And a sensing lever plate rotatably supported on the side surface of the support fitting, and a rotation amount regulating device for the sensing lever plate provided on the support fitting. . 2. The joint points between the sensing lever plate and the connecting mechanism are provided at two upper and lower positions in front of the rotation fulcrum of the sensing lever plate, and the connecting mechanism is selectively attached to either one of the joint points. 2. The work machine lifting / lowering control device according to claim 1, wherein the connecting mechanism is arranged so as to be able to respond to a constant tension or compression direction regardless of whether the sensing lever plate is rotated in the forward or reverse direction.