JPH10168930A - Automatic position controller for side dump bucket - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control a bucket after dumping to the side automatically up to a horizontal place without requiring wasteful operation in a working machine with the side dump bucket. SOLUTION: The automatic position controller has housing detecting means 32, 33 detecting upward housing at an original place after the side dump bucket 3 installed to the front and the rear in a manner that the bucket 3 can be dumped by extending and retracting a tilt cylinder 5 is dumped to the side. The automatic position controller is composed of the housing detecting means 32, 33 and a pressure-oil supply means 34 being connected at the rear stages of the housing detecting means 32, 33, supplying the tilt cylinder 5 with pressure oil on the basis of housing detecting signals from the housing detecting means 32, 33 and dumping the bucket 3 in the forward direction, stopping the supply of pressure oil when the bucket 3 is brought to a horizontal state and holding the bucket 3 at a horizontal place.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic bucket position control device for automatically controlling a bucket to a horizontal position after dumping a side dump bucket capable of dumping the bucket forward and sideways.

[0002]

2. Description of the Related Art A vehicle with a bucket carries out a loading operation by repeating a series of operations of scooping up a load such as earth and sand, rocks, and the like, and then lifting the bucket and damping it with a truck vehicle. Conventionally, as an automatic position control device for a bucket of a vehicle with a bucket, after dumping and discharging earth and sand, the bucket is automatically operated and held to a horizontal position to prepare for the next operation. The automatic bucket position control device is provided mainly for a case where the bucket is dumped forward to discharge earth and sand. That is, as shown in FIG. 11, when the bucket 103 is in the front dump position where the earth and sand are discharged, the operator causes the bucket 103 to operate to the rack back position by operating the tilt lever. Then the switch is O
N, the automatic control is started, the bucket 103 is dumped forward, and when the bucket 103 reaches the horizontal position, the switch is turned off and held at the horizontal position.

[0003] In the case of a side dump bucket, which is one type of bucket, the earth and sand in the bucket is dumped forward and then dumped to the side in order to discharge the earth and sand from the bucket. With reference to FIG. 12, a series of steps in which the side dump bucket is used to perform a damping operation to the side by a manual operation will be described. In the figure, 3 is a side dump bucket, 1 is a lift arm for raising and lowering the bucket, 5
Reference numeral 3 denotes a vehicle wheel provided with a side dump. Also,
7, 30, and 54 indicate various operation levers, 7 is a tilt lever for tilting the bucket in the front-rear direction, 54 is a lift lever for moving the lift arm up and down, and 30 is a side dump or a side dump from the side dump position to the original position. The side dump lever stored at the rack back position is shown. With the bucket 3 in the horizontal position on the ground,
The vehicle is moved forward to scrape earth and sand into the bucket 3. Tilt lever 7 is tilted backward to move bucket 3 to the rack back position. Tilt the lift lever 54 backward and lift the lift arm 1
To the raised position. When the lift arm 1 reaches the uppermost position, the lift lever 54 is detented OFF (released). Next, the side dump lever 30 is tilted rearward, and the bucket 3 is damped to the side to discharge the earth and sand. By tilting the side dump lever 30 forward, the bucket 3 is stored at the original position (rack back position). Tilt lever 7 is tilted forward to move bucket 3 to the horizontal position. Tilt the lift lever 54 forward and move the lift arm 1
To the lower position. The bucket 3 is held horizontally on the ground. As described above, in the case of manual operation, it is difficult to cause the bucket 3 to be dumped forward so as to be stopped and held at an accurate horizontal position, so that considerable experience and skill are required for the operator.

Here, in order to operate and hold the bucket 3 at a horizontal position, the following operation is required in the case of automatic control by a conventional automatic control device. That is, the operator operates the side dump lever 30 to return the bucket 3 to the storage position (the state), and then switches the tilt lever 7 to dump the bucket 3 forward from the storage position (the state). Thereafter, the automatic control operation is not started unless the rack is raised to the rack back position again. As described above, the conventional automatic control mainly deals with the case where the bucket 3 is dumped forward to discharge the earth and sand, and as a result, a wasteful operation is required for the operator, and the operability is impaired. .

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances.
An object of the present invention is to provide an automatic bucket position control device that can automatically control a side dump bucket to a horizontal position without needless operation of a laterally dumped bucket.

[0006]

In order to solve this problem, the automatic position control device for a side dump bucket according to the present invention has a bucket position detecting device provided so as to detect a forward dump position and a rack back position of the bucket. Means,
The bucket position detecting means is connected to a tilt lever for controlling the tilting of the bucket and is provided in conjunction with a tilt lever. The bucket position detecting means detects that the bucket is at the front dumping position, and the tilt lever moves to the rack back position side. When it is operated, the bucket is dumped forward and automatically controlled to hold it in the horizontal position, the bucket position detecting means detects that the bucket is at the rack back position, and the tilt lever is operated to the front dump position side And a controller for automatically controlling the bucket to be dumped forward and held at a horizontal position. Therefore,
When the control unit detects that the bucket is at the rack back position (storage position) from the bucket position detecting means and operates the tilt lever to the front dump position side, the bucket is dumped forward and held at the horizontal position. Command signal for automatic control as described above. Here, in the invention of claim 2, the bucket position detecting means includes a detector provided on the bucket or the tilt cylinder, and a sensor for detecting the detector at a dump position and a rack back position of the bucket. Further, in the invention according to claim 3, the control unit is provided with a solenoid coil on the dump side and a solenoid coil on the rack back side connected to the subsequent stage of the bucket position detecting means, and is provided so as to interlock with the operation of the tilt lever. And a command signal for operating and holding the bucket at the horizontal position based on the detection signal input from the bucket position detecting means and the operation of the tilt lever.

According to a fourth aspect of the present invention, there is provided an automatic position control device for a side dump bucket, wherein the storage detecting means detects that the bucket has been dumped laterally and then stored upward in its original position. A pressure oil is supplied to the tilt cylinder based on the storage detection signal from the storage detection means, and the bucket is dumped forward. When the bucket is horizontal, the supply of the pressure oil is stopped and the bucket is moved to the horizontal position. And a pressure oil supply mechanism for holding the pressure oil. Therefore, after the bucket is dumped to the side and the storage detecting means detects that the bucket is stored upward in the original position, the pressure oil supply mechanism supplies pressure oil to the tilt cylinder based on the storage detection signal. Then, the bucket is dumped forward, and when the bucket becomes horizontal, the supply of the pressure oil is stopped and the bucket is held at the horizontal position. In the invention according to claim 5, the storage detecting means detects the bucket storing operation of the side dump lever, and the second detecting means detects that the bucket has returned from the side dump position to the storing position. Pressure oil supply means is interposed between the first detection means and the second detection means and the dump side of the main valve of the tilt cylinder, and is connected to the first detection means and the second detection means. The control valve is configured to supply pilot pressure oil to the dump side of the main valve of the tilt cylinder when a storage detection signal is input from the second detection means.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to FIGS. FIG. 2 shows an example of a working machine with a side dump bucket. The work machine includes a lift arm 1 having a base end pivotally attached to a vehicle (not shown), a lift cylinder 2 for raising and lowering the lift arm 1, and a pivotal arm at the tip end of the lift arm 1 for tilting in the front-rear direction and sideways. The vehicle includes a mounted side dump bucket 3 and a tilt cylinder 5 for tilting the bucket 3 via a tilt link lever 4.

FIG. 1 shows an embodiment of an automatic position control device for a side dump bucket for controlling the position of the bucket 3 of the work machine shown in FIG. The automatic position control device for the side dump bucket automatically stores the bucket dumped laterally at the original position, and then dumps the bucket forward from the storage position (rack back position) to the horizontal position. It is controlled to operate and hold.

That is, the apparatus comprises a bucket position detecting means 6 for detecting the position of the bucket, and a control unit for automatically controlling the bucket by operating the tilt lever 7 and a bucket position detection signal inputted from the bucket position detecting means 6. And a pilot valve 8. Here, in this embodiment, the bucket position detecting means 6 is provided so as to detect the position of the bucket 3 based on the extension and contraction of the pin 9 of the tilt cylinder 5. As shown in FIGS. 1 and 3 to 5, the bucket position detecting means 6 of this embodiment includes a pair of magnets 10 and 11 shown as an example of a detector fixed to the pin 9 of the tilt cylinder 5. ,
A pair of sensors 12 and 13 for dump detection and rack back detection fixed to the vehicle body are provided.

The magnets 10 and 11 extend the pins 9.
Moved with shortening, dump position indicated by 14, 15
The rack is displaced to a horizontal position indicated by, and a rack back position indicated by 16. The dump detection sensor 12 is provided to be turned on when one of the magnets 10 is at the dump position 14. The sensor 13 for detecting the rack back is provided to be turned on when the other magnet 11 is at the rack back position 16.

The pilot valve 8 is connected to the sensor 1
The tilt lever 7 is connected to the rear side of the second and the third lever 13 and is provided so as to interlock with the movement of the tilt lever 7. Tilt lever 7
Is operated by an operator, and is provided so that a dump position 17, a neutral position 18, and a rack back position 19 can be selected. The pilot valve 8 outputs a command signal for automatically operating and holding the bucket 3 at a horizontal position based on the detection signals input from the sensors 12 and 13 and the operation of the tilt lever 7.

The conditions for issuing the automatic control command signal are as follows:
It is as follows. When the bucket is dumped forward, as shown in FIG. 11, a direction in which the bucket 103 is moved from the dump position (rackback position direction).
, The bucket 103 is automatically controlled to the horizontal position. Further, when the bucket is dumped to the side, as shown in FIG. 2, when the bucket 3 is operated from the rackback position where the bucket 3 is returned to the damping position, the bucket 3 is automatically controlled to the horizontal position. The pilot valve 8 includes a solenoid coil 20 on the dump side,
A solenoid coil 21 on the rack back side is provided. The dump side solenoid coil 20 is connected to a stage subsequent to the dump detection sensor 12.

The solenoid coil 21 on the rack back side
Is connected to the rear stage of the sensor 13 for detecting the rack back. 22 and 23 are energized solenoid coils 2
The plate sucked at 0, 21 is shown. The solenoid coil 20 on the dump side is provided with a sensor 12 for dump detection.
When the tilt lever 7 is moved to the rack back position 19 side in a state where the dump detection signal is input from the controller 3, the tilt lever 7 is turned on to output a command for automatically operating the bucket 3 to the horizontal position. On the other hand, the solenoid coil 21 on the rack back side is provided with a sensor 13 for rack back detection.
When the tilt lever 7 is moved to the dump position 17 in a state where the rack back detection signal is input from the controller 3, the tilt lever 7 is turned on to output a command for automatically operating the bucket 3 to the horizontal position.

The solenoid coils 20, 2
1, the hydraulic mechanism automatically operates the lift cylinder 2 and the tilt cylinder 5 to operate the lift arm 1 and the bucket 3 and the bucket 3
Is moved to the horizontal position (see FIG. 2).
According to the automatic position control device of the bucket configured as described above, after damping laterally or forward as follows,
Automatic control is performed so that the bucket 3 is operated and held horizontally.

[When dumping forward and releasing earth and sand] When dumping the bucket forward and discharging the earth and sand,
Magnet 1 provided on pin 9 of tilt cylinder 5
0 is the dump position 14, the sensor 12 is turned on, and a dump detection signal is output. This dump detection signal is input to the solenoid coil 20 on the dump side of the pilot valve 8. When the tilt lever 7 is operated to the rack back position 19 by the operator while the dump detection signal is being input to the dump side solenoid coil 20, the dump side solenoid coil 20 is turned on and outputs a command signal. By the output of this command signal, the bucket is automatically operated and held at the horizontal position. This operation is similar to the operation in FIG.

[When the side dumps and releases earth and sand]
The bucket 3 is tilted laterally on a truck vehicle or the like to perform damping, and the earth and sand is discharged to the bed of the truck vehicle.
(The state of the side damping is not shown.) When the side damping is performed in this manner, the magnet 11 provided on the pin 9 of the tilt cylinder 5 reaches the rack back position 16, the sensor 13 is turned on, and the rack back is detected. A signal is output.

This rackback detection signal is input to the solenoid coil 21 on the rackback side of the pilot valve 8. When the operator operates the tilt lever 7 to the dump position 17 while the rack back detection signal is input to the rack back side solenoid coil 21, the rack back side solenoid coil 21 is turned on,
Outputs command signal. By the output of this command signal, the tilt cylinder 4 and the lift cylinder 2 are automatically operated, and the lift arm 1 and the bucket 3 are operated.
The bucket 3 is operated and held at a horizontal position.

This operation will be described with reference to FIG. 2. When the bucket 3 is dumped to the side and returned to the rack back position (storage position), the bucket 3 is moved to the dump position by operating the tilt lever. When moved, the bucket 3 is automatically moved to the horizontal position. In the above-described embodiment, the dumping of the bucket 3 is detected based on the extension / shortening of the pin 9 of the tilt cylinder 5, but the invention is not limited to this. Position detecting means can be employed.

FIGS. 6 to 10 show different embodiments of the automatic position control device for the side dump bucket according to the present invention. The automatic bucket position control device of this embodiment is
It is provided that the automatic control starts to operate just by storing the bucket damped to the side. 6, reference numeral 3 denotes a bucket in a side damping and stored state, 5 denotes a tilt cylinder, 30 denotes a side dump lever, and 31 denotes a tilt main cylinder that supplies pressure oil to the tilt cylinder 5. For this configuration,
A mechanism of an automatic bucket position control device for linking a tilt circuit with a side dumb circuit is added as follows.

This automatic bucket position control device is provided on the side dump lever 30.
The limit switch 32 is shown as an example of a first detecting means that is turned on when is operated in the storage direction, and a second switch provided on the linkage of the bucket 3 is turned on when the bucket 3 is returned from the side dump position to the storage position. A limit switch 33 shown as an example of a detection means, an electromagnetic solenoid valve 34 which is energized when both the first limit switch 32 and the second limit switch 33 are turned on to open the spool and flow pilot pressure oil, A first level positioner 35 (particularly (d) in FIG. 7) is provided on the tilt cylinder 5 and is turned off when the bucket 3 dumps forward and reaches a horizontal position.

When the pressure oil from the electromagnetic solenoid valve 34 flows into the front dump side, the tilt main cylinder 31 opens the spool and sends the pressure oil supplied from a pump (not shown) to the lot end side of the tilt cylinder 5 (not shown). (The direction of dumping in front of the bucket). Therefore, when the bucket 3 is stored at the original position after the side damping, the operation of the tilt cylinder 5 acts to dump the bucket 3 forward.

When the side dump lever 30 is operated in the storage direction by the first limit switch 35, the bucket 3 is completely returned to the storage position by the second limit switch 33. Is detected, the pilot pressure oil is supplied and bucket 3
To dump forward. This is to ensure the safety by preventing the bucket 3 from operating when the bucket 3 is not completely stored.

As shown in FIG. 8, the side dump lever 30 has a P port 36 on the pressure oil supply side, a T port 37 on the tank return side, a side dump side outlet 38 and a storage side outlet 39 for the pressure oil. First and second plunger assemblies 41 and 4 provided so that either one of the casing 40 and the side dump lever 30 is pulled up when the side dump lever 30 is operated to the side dump side or the bucket storage side.
2, a return spring 43, 44 provided on each plunger assembly 41, 42, and a holding coil assembly 45 provided only on the second plunger assembly 42 side. In the figure, reference numeral 46 denotes a solenoid coil wiring, which is connected to a first level positioner 35 provided in the tilt cylinder 5.

When the side dump lever 30 is operated to the side dump state as shown in FIG. 8A, the pressure oil is supplied to the outside from the side dump side outlet 38, and the bucket 3 is side dumped. On the other hand, when the side dump lever 30 is operated to store the bucket, pressure oil is supplied to the outside from the storage side outlet 39, and the bucket 3 is stored. Further, when the side dump lever 30 is in the retracted state as shown in FIG. 8C, the second plunger assembly 42 is pulled up and comes into contact with the holding coil assembly 45 to be excited. The lever 30 is held in this stored state.

When the bucket 3 is dumped forward and reaches the horizontal position and the first level positioner 35 is turned off, the side dump lever 30 in the bucket storage state demagnetizes the holding coil assembly 45 to maintain the bucket storage state. Is automatically released and automatically set to a neutral state as shown in FIG. 8 (b). When the side dump lever 30 is in the neutral state, the first limit switch 32 provided on the side dump lever 30 is turned off, so that current does not flow.
4 is also turned off, and the supply of pressure oil to the rod end side of the tilt cylinder 5 is stopped. As a result, bucket 3
Held in a horizontal position.

The check valve 47 shown in FIG.
It is connected between the electromagnetic solenoid valve 34 and a pilot valve 48 of the tilt lever 7. The check valve 47 is provided to prevent the pressure oil from erroneously flowing toward the pilot valve 48 of the tilt lever 7 while the electromagnetic solenoid valve 34 is operating.

This embodiment is provided so as to be switchable to a manual operation method by an operator in addition to the automatic control method by the automatic position control device for the side dump bucket described above. That is, the switching switch 50 is provided between the power supply 49 and the automatic bucket position control device. Reference numeral 51 denotes a pilot lamp. Therefore, the operator can select either the automatic control or the manual control using the switch 50 at hand.

The mechanism described above relates to a mechanism for automatically moving the bucket 3 to the horizontal position when the side dump is performed and the earth and sand is discharged. It also has a function to automatically move the bucket to a horizontal position. That is, the tilt cylinder 5 is provided with the second level positioner 52.

The second level positioner 52 is turned on when the bucket 3 moves from the rack back state to the forward dump position to start automatic control, automatically raises the bucket 3, and turns off when the bucket 3 reaches the horizontal position. , And are held in a horizontal position. In FIG. 7, 5
Numeral 5 indicates a kick-out positioner of the lift arm. According to the automatic bucket position control device configured as described above, the bucket 3 is automatically operated to the horizontal position and held as described below.

[When dumping forward and releasing earth and sand] The tilt lever 7 is tilted forward as shown in FIG. 9B, and the bucket storing the earth and sand is moved to the rack back position as shown in FIG. 9A. From the front dump position to release the earth and sand. When the bucket 3 is moved from the rack back position to the forward dump position, the second level positioner 52 (see FIG. 7C) provided in the tilt cylinder 5 is turned on, and the bucket 3 is automatically turned on. From the forward dump position.

At this time, the tilt lever 7 automatically moves to the rack back position as shown in FIG. Then, when the bucket 3 reaches the horizontal position, the second level positioner 52 is turned off and holds the horizontal position. At this time, the tilt lever 7 is
As shown in (e), the detent is turned off and automatically moves to the neutral position.

[When dumping earth and sand by side dumping]
When the side dump lever 30 is operated to the side dump position as shown in FIG. 8A, the bucket 3 is dumped to the side and the earth and sand is discharged. Next, when the side dump lever 30 is operated from the side dump position to the bucket storage position as shown in FIG. 8C, the bucket 3 is moved in the direction to store the bucket 3 as shown by the arrow in FIG.

When the side dump lever 30 is operated in the storage direction, the first limit switch 32 is turned on in conjunction with this operation (see FIG. 6). Further, the side dump lever 30 is held at the storage position. Then, when the bucket 3 is completely returned to the storage position as shown in FIG. 10B, the second limit switch 33 provided on the bucket linkage is turned on. Both the first limit switch 32 and the second limit switch 33 are ON
By doing so, the electromagnetic solenoid valve 34 is energized, the spool opens, and the pilot pressure oil flows.

When the pilot pressure oil from the electromagnetic solenoid valve 34 flows into the front dump side of the tilt main cylinder 31, the spool is opened and the pressure oil supplied from a pump (not shown) is supplied to the lot end of the tilt cylinder 5. To the side (bucket forward dump direction). as a result,
The tilt cylinder 5 is extended, and the bucket 6 is dumped forward as shown in FIG.

When the bucket 3 dumped forward reaches the horizontal position, the first level positioner 35 provided in the tilt cylinder 5 is turned off. When the first level positioner 35 is turned off, the holding coil 45 provided on the side dump lever 30 is demagnetized, and the holding state of the side dump lever 30 is released, and as shown in FIG. A neutral state is established. When the side dump lever 30 is in the neutral state, the first limit switch 32 is turned off in conjunction with the operation of the side dump lever 30, and no current flows.
Is also turned off, and the supply of pressure oil to the rod end side of the tilt cylinder 5 is stopped. Therefore, bucket 3
It is kept horizontal.

According to this embodiment, the tilt operation can be automatically performed by operating only the side dump lever 30 without operating the tilt lever 7. In the present invention, the configuration of various detection means is not limited to the above-described embodiment, and various types of contact and non-contact sensors and switches can be used. In addition, it goes without saying that various design changes can be made without departing from the scope of the present invention.

[0038]

According to the automatic bucket position control device of the present invention described above, the following effects can be obtained. (1) According to the automatic position control device for the side dump bucket according to the first aspect, when a signal indicating that the bucket is stored and at the rack back position is input and the tilt lever is operated to the front dump position, the bucket is automatically moved. Dump forward and hold in horizontal position. Therefore, it is possible to automatically control the laterally damped bucket to a horizontal position while minimizing useless operations. (2) According to the automatic position control device for the side dump bucket of claim 4, after the bucket is dumped to the side,
When it is detected that the bucket is stored at the original position, the bucket is dumped forward, and the bucket is held at the horizontal position. Therefore, the laterally damped bucket can be automatically controlled to the horizontal position without any useless operation.

[Brief description of the drawings]

FIG. 1 is a first view of a bucket automatic position control device according to the present invention.
It is a circuit diagram of an example.

FIG. 2 is an operation state diagram showing an operation of the working machine of the first embodiment.

FIG. 3 is a partially enlarged view of the working machine shown in FIG. 2;

4 is a partially cutaway view of a portion viewed from the line IV-IV in FIG. 3;

FIG. 5 is a detailed circuit diagram of the first embodiment.

FIG. 6 shows a second embodiment of the automatic bucket position control device of the present invention.
It is a detailed circuit diagram of an example.

FIGS. 7A and 7B are partially enlarged views of a working machine equipped with the automatic bucket position control device of the second embodiment, wherein FIG. 7A is a side view of a lift arm and a tilt cylinder, and FIG. -B
FIG. 2C is a plan view as viewed from the direction of the arrow, FIG. 3C is a partially broken view as viewed from the direction of the arrow CC in FIG. FIG. 4D is a cross-sectional view taken along the line EE in FIG.

8A and 8B are longitudinal sectional views illustrating a side dump lever according to a second embodiment, in which FIG. 8A illustrates a state where the lever is in a bucket side dump state, and FIG. 8B illustrates a state where the lever is in a neutral state. FIG. 3C is a diagram illustrating a state where the lever is in a bucket storage state.

9A and 9B are operation state diagrams showing automatic control in the case of front damping according to the second embodiment, wherein FIG. 9A is a side view of a bucket dumped forward, and FIG. 9B is a view showing the operation of the tilt lever in FIG. FIGS. 7C and 7C are diagrams illustrating a state in which the front dumping state is automatically controlled to the horizontal position, and FIGS. 7D and 7E are diagrams illustrating the operation of the tilt lever in the case of FIG.

10A and 10B are operation state diagrams showing automatic control in the case of side damping according to the second embodiment, wherein FIG. 10A is a front view of a bucket at a side dump position, and FIG. 10B is a view of a bucket returned to a storage position. Side view, (c) state diagram of side dump lever when returning bucket from side dump position to storage position, (d) diagram showing state automatically controlled from storage position to horizontal position, (e) diagram (d) It is a figure showing operation of a side dump lever at the time of.

FIG. 11 is a state diagram showing the operation of the bucket by the conventional automatic bucket position control device.

FIG. 12 is an operation state diagram showing a series of operations when the bucket is completely side-damped by manual operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lift arm 2 Lift cylinder 3 Bucket 5 Tilt cylinder 6 Bucket position detecting means 7 Control lever 8 Pilot valve (control part) 9 Pin 10 Dump side magnet 11 Rack back side magnet 12 Dump side sensor 13 Rack back side sensor Reference Signs List 20 solenoid coil on dump side 21 solenoid coil on rack back side 30 side dump lever 31 main cylinder for tilt 32 first limit switch 33 second limit switch 34 electromagnetic solenoid valve 35 first level positioner 45 holding coil・ Assembly 52 2nd level positioner

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] March 21, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Fig. 7

[Correction method] Change

[Correction contents]

FIGS. 7A and 7B are partially enlarged views of a working machine equipped with the automatic bucket position control device of the second embodiment, wherein FIG. 7A is a side view of a lift arm and a tilt cylinder, and FIG. -B
FIG. 2C is a plan view as viewed from the direction of the arrow, FIG. 3C is a partially broken view as viewed from the direction of the arrow CC in FIG. (E) is a cross-sectional view as viewed from the direction of the arrow EE in FIG.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shuji Ishida 4-10-1, Yoga, Setagaya-ku, Tokyo New Caterpillar Mitsubishi Corporation

Claims (5)

[Claims] 1. A bucket position detecting means provided to detect a forward dump position and a rack back position of a bucket, and interlocked with a tilt lever connected to the bucket position detecting means and controlling tilting of the bucket. The bucket position detecting means detects that the bucket is at the front dump position, and when the tilt lever is operated to the rack back position side, automatically controls the bucket to dump forward and hold the horizontal position. A control unit that automatically controls the bucket position detecting means to detect that the bucket is at the rack back position and to automatically control the bucket to be dumped forward and held at a horizontal position when the tilt lever is operated to the forward dump position side. And an automatic position control device for a side dump bucket. 2. A bucket position detecting means comprising: a detector provided on a bucket or a tilt cylinder; and a sensor for detecting the detector at a dump position and a rack back position of the bucket. Item 2. The automatic position control device for a side dump bucket according to Item 1. 3. A pilot unit, wherein a control unit is provided with a solenoid coil on the dump side and a solenoid coil on the rack back side connected to the subsequent stage of the bucket position detecting means, and is provided so as to interlock with the operation of the tilt lever. 3. A command signal for operating and holding a bucket at a horizontal position based on a detection signal input from a bucket position detecting means and an operation of a tilt lever, comprising a valve. 2. The automatic position control device for a side dump bucket according to 2. 4. After the bucket has been laterally damped,
Storage detecting means for detecting that the storage position has been stored upward in the original position; and a bucket connected to the subsequent stage of the storage detecting means for supplying pressure oil to the tilt cylinder based on a storage detection signal from the storage detecting means. And a pressure oil supply means for stopping the supply of pressure oil when the bucket becomes horizontal and holding the bucket in a horizontal position. 5. A storage device comprising: first detection means for detecting a bucket storage operation of a side dump lever; and second detection means for detecting that a bucket has returned from a side dump position to a storage position. Pressure oil supply means,
When the storage detection signals from the first detection means and the second detection means are connected and connected between the first detection means and the second detection means and the dump side of the main valve of the tilt cylinder, 5. The automatic position control device for a side dump bucket according to claim 4, further comprising a control valve for supplying pilot pressure oil to a dump side of a main valve of the tilt cylinder.