JPH01271529A - Automatic offsetting mechanism of small revolution type backhoe - Google Patents

Abstract

PURPOSE:To enhance the safety by folding a boom and an arm for accommodation of a bucket at the side of a cabin, and returning the bucket automatically to the accommodation position with maneuvering of a control lever to the accommodation side. CONSTITUTION:When the offset prohibited area as a hazardous area is approached, a boom solenoid proportional valve 37 and an arm solenoid proportional valve 38 are switched over to the port on the opposite side to operation of a manual control valve so as to stop rotation, when an offset solenoid proportional valve 39 is solely turned on. Then the level of a bucket 1 is checked to know whether or not the level is over the setting given by a bucket level setting switch 34. When an arm control lever 9a or a boom control lever is tuned fully, the proportional valve 39 is actuated to cause commencement of automatic return of bucket 1 to the accommodation position. When the bucket 1 is restituted to the standard position, the proportional valve 39 is switched over to the neutral.

Description

[Detailed description of the invention] (a) Industrial application field The present invention is a backhoe device in which the bucket, arm, and boom are bent in order to minimize the turning radius of the swivel table when the bucket is stored. In addition, in order to facilitate ditch excavation, the arm of this small-swing type backhoe is placed in a position parallel to the left and right sides of the traveling direction. This relates to a mechanism that enables offset movement.

(B) Prior Art Conventionally, in a backhoe, there is a known technique for stopping the arm when the arm approaches a certain level or more and becomes dangerous.

For example, as in Japanese Utility Model Publication No. 58-12926.

There is also a known technique for offsetting the arm and bucket of a backhoe to parallel positions with respect to the direction of travel, as disclosed in, for example, Japanese Patent Publication No. 40-20879.

(c) Problems to be Solved by the Invention The present invention enables the bucket to be stored on the side of the cabin in order to enable the swivel table to rotate even in a particularly narrow space, and furthermore, the bucket and the arm portion can be moved to the left or right in the direction of travel. If the operator pulls the bucket back to the storage position without noticing it when the bucket is offset to the left or right, the bucket will interfere with the cabin and destroy it, causing the operator to be injured. If you return the bucket to its stored state, be sure to avoid damaging it.
The bucket is configured to automatically return to the storage position even if the operator does not intend to do so.

In addition, if the operation of returning the bucket to the storage position and the operation of attracting the bucket by operating the operating lever were separately possible, it would take time to operate the bucket. This allows the operation and the automatic control operation of returning the bucket to the storage position to be performed in parallel.

In addition, if the operator releases the control lever from the full operation position to store the bucket, it is possible that some dangerous situation may have occurred, so the action to return the bucket to the stored position must be made at that moment. It is configured to stop at a certain position. This gives priority to manual operation using the operating lever.

In addition, if the automatic return operation from the offset position is started immediately in conjunction with the bucket pulling operation, the automatic offset will start from the position where the bucket is close to the ground surface and there is a steel sheet pile, etc. standing to the side. Because of this, the bucket could be destroyed or the steel sheet pile could fall, so a height setting device was installed to make it possible to set the starting height for automatic offset return control.

In addition, it is common to prepare several types of buckets 1 with different widths for the buckets attached to the tip of the arm, so if the storage position is set with a narrow bucket, a wide bucket can be attached. If this happens, the bucket and the cabin will interfere with each other, so the storage position of the bucket can be automatically changed when the bucket is replaced.

(d) Means for Solving the Problems The objects of the present invention are as described above. Next, the configuration for achieving the objects will be explained.

An arm 4 is supported at the tip of a boom 6 which is pivotally supported on a swivel table 12 so as to be vertically movable, and can be offset to left and right parallel positions, and a bucket 1 is rotatably attached to the tip of the arm 4. , in a configuration in which the boom 6 and the arm 4 are folded to allow the bucket 1 to be stored on the side of the cabin 2 when turning, the bucket 1 is automatically returned to the storage position by operating the operating lever to the storage side. It is automatically controlled as much as possible.

Furthermore, by operating the operating lever toward the storage side of the bucket 1, the operation of returning the offset cylinder 3 to the storage position and the operation of drawing the bucket 1 to the side of the boom 6 are performed at the same time.

Also, an operating lever 9 for operating the bucket 1 to the storage side
When the operator releases his/her hand from the full operating position, the bucket is configured to stop at the instantaneous 1 position.

Further, the offset movement is automatically started only when the bucket 1 rises above a certain height set by the height setting device.

Further, buckets 1 of different widths can be selectively attached to the tip of the arm 4, and by replacing the buckets 1, the bucket storage position can be automatically changed.

(E) Embodiment The object and structure of the present invention are as described above. Next, the structure of the embodiment shown in the attached drawings will be explained.

FIG. 1 is a plan view of a small swing type backhoe according to the present invention, and FIG. 2 is a side view of the same (in a working state).

In the backhoe, a swivel base bearing 13 is disposed on a crawler type traveling device 11 to which a soil removal plate 10 is attached, and a swivel base 12 is disposed on the swivel base bearing 13. The swivel base 12 is capable of horizontal rotation of 360 degrees.

In addition, the cabin 2 is arranged in the left half above the swivel base 12, the engine and balance weight are placed in the rear part, and the swivel base 1
The base of the boom 6 is pivotably supported at a position substantially in the middle of the boom 6 so as to be movable up and down.

A boom cylinder 5 is disposed between the boom 6 and the swivel base 12, and the boom 6 is configured to be able to rotate up and down by expanding and contracting the boom cylinder 5.

An offset arm 22 and a parallel link 23 are arranged at the tip of the boom 6, and an offset cylinder 3 is interposed between the offset arm 22 and the boom 6. As the offset cylinder 3 expands and contracts, the offset arm 22 and the parallel link 23 rotate left and right, and the arm 4 supported at the tip of the arm 4 moves horizontally in an offset manner in parallel.

An arm 4 is pivotally supported at the tip of the offset arm 22, and the cylinder is rotated up and down by an arm cylinder 24 disposed within a cover integrally constructed with the offset arm 22.

Further, the bucket 1 is pivotally supported at the tip of the arm 4, and the arm 4 is capable of scooping and rotation by the bucket cylinder 7.

In the overall configuration as described above, a boom sensor 15 configured with a potentiometer or the like is arranged at the base of the boom 60 to detect the rotation angle of the boom 6.
Further, an offset sensor 16 configured with a potentiometer is arranged at the base of the parallel link 23 to detect the left and right offset angle of the offset arm 22, and an arm sensor 17 for detecting the rotation angle of the arm 4 is located at the tip of the offset arm 22. It is located at the pivot point of arm 4.

Further, a lever sensor 14 is arranged at the base of the operating lever 9 to detect when the operating lever 9 is operated in order to rotate the boom 6 or the arm 4. Further, an offset pedal 29 for operating the offset of the arm 4 is arranged below the operating lever 9, and an offset pedal sensor 28 is arranged at the base of the offset pedal 29.

The electromagnetic proportional valve device 20 is installed in the oil supply path of the boom cylinder 5, arm cylinder 24, and offset cylinder 3, and is used to perform a shockless stop.

Further, a controller 21 is arranged below the seat 8.

Inside the controller 21, there is an analog/digital conversion circuit A/D shown at the bottom of FIG. 4, a central processing circuit CPU, an interface I10, a buffer circuit, a driver circuit, a discrete circuit, a power cutoff circuit, etc. A power supply circuit is arranged to perform control operations.

In addition, in FIG. 4, an ultrasonic sensor 19 and a touch sensor 18 are attached to the upper part of the cabin 2, and when the automatic control goes out of control and becomes ineffective and the bucket 1 approaches the position where it touches the cabin 2, the Bucket 1
A double safety device is configured to stop the robot from being drawn to the storage position and to issue an alarm.

Further, as shown in FIG. 3, a bucket sensor 26 is arranged at the tip of the arm 4 in order to automatically change the bucket width when the bucket 1 is replaced, and the arm 4 is provided for each bucket 1. The configuration is such that switching can be performed by changing the bucket width recognition body 25. The bucket width recognition body 25 may be made of a magnetic material.

(F) Function of the Invention The structure of the automatic offset mechanism for the small swing type backhoe of the present invention is as described above, and the present invention will now be described in detail with reference to the control flowcharts of FIGS. 5 and 6.

FIG. 5 mainly shows a flowchart of automatic offset and shockless stop control.

When the automatic switch 35 constituted by a push-lock type switch is turned on at the same time as the engine is started with the key, automatic control of the small swing type backhoe of the present invention is started.

At the same time, the circuit power of the controller 21 and the electromagnetic proportional valve device 20 is turned on.

Next, it is checked whether the potentiometers constituting the angle sensors of each part are operating normally. If the potentiometers are abnormal in the automatic control state, the alarm lamp 30 on the operation panel 27 and the alarm buzzer 31 is ON
This alerts the operator to danger.

Next, it is checked whether the width of bucket 1 is standard. Whether the bucket 1 is standard or wide is input using the bucket width adjustment 33, which is composed of a non-locking push-in switch, and is set to the wide bucket 1 in the normal automatic start state. When changing to a narrow standard bucket, if the bucket width switch 33 is pressed, control is started so that the storage position of the bucket 1 is set to the narrow width position closest to the cabin 2. be.

Even if the width is changed to narrow, if the bucket width switch 33 is set to the wide bucket 1 position, the narrow bucket will
Normally, the bucket 1 is stored in a safe position with a space between it and the cabin 2.

Next, it is checked whether the control start height has been set by the bucket height setting switch 34.

The bucket height setting switch 34 is configured as a rotary switch, and a position for turning off the offset control is also provided below the minimum height, and the automatic switch 3
5 is not turned on, the offset is performed by operating the offset pedal 29 under the operator's intentional operation.

Further, when the automatic switch 35 is ON and the bucket height setting switch 34 is OFF, the ultrasonic sensor 19
Although there are danger displays using the touch sensor 18 and shockless stopping of the boom 6, arm 4, and offset arm 22, offset control is not performed.

When excavation work is started and the boom 6, arm 4, and offset arm 22 are rotated, a check is first made to see if the arm operating lever 9b or 9a is fully operated.

When either operating lever 9 is fully operated by the operator, the boom electromagnetic proportional valve 37 or the arm electromagnetic proportional valve 38 is operated by the A boat, which is the boat on the same side as the manually operated control valve. turns on,
A seventh cylinder is attached to each boom cylinder 5 and arm cylinder 24.
It becomes possible to send pressure oil as controlled by the boom manual control valve 40 and the arm manual control valve 41 shown in the figure.

As a result, the boom 6 or the arm 4 starts rotating in the direction operated by the control lever 9. However, if the operator grasps either control lever 9 and moves the lever from the fully operated state to the neutral position, , the oil path by the manual operation valve is switched and the rotation is about to stop, but the boom electromagnetic proportional valve 37 or the arm electromagnetic proportional valve 38 senses this and turns off the A boat of the electromagnetic proportional valve on the same side. The oil level is gradually adjusted through operation, resulting in a shockless stop.

That is, until then, the arm solenoid proportional valve 38 or the boom solenoid proportional valve 37 was switched to the A boat side by turning on the solenoid, but by moving the operating lever 9 to near the neutral position, the solenoid on the A boat side is turned OFF. Therefore, the proportional valve operates later than the manual valve and gradually stops.

Also, even if one of the operating levers 9 is slightly operated, the boom 6 or arm 4 is in a rotating state, and the bucket 1 is in a dangerous position on either side where it will interfere with the cabin 2 if it is rotated as it is. If the position is in the danger zone on the left or right, turn on the boat on the side opposite to the manual operation control valve of the boom solenoid proportional valve 37 or the arm solenoid proportional valve 38, and manually operate the valve. By releasing the pressure oil sent from the control valve to the tank circuit using the electromagnetic proportional valve, it is turned off in a shockless state and the rotation of the boom 6 and arm 4 is stopped until the offset position returns to the safe position. be.

When approaching the set danger area, the offset prohibited area a, the boom solenoid proportional valve 37 and the arm solenoid proportional valve 38 are switched to the boat on the opposite side of the manually operated control valve. FIG. 8 shows an operating procedure for stopping the movement, turning on only the offset electromagnetic proportional valve 39, and returning the bucket 1 to the standard position where it can be stored.

Next, the height of the bucket 1 is checked, and only when the height is equal to or higher than the height set by the bucket height setting switch 34, automatic return to the offset reference storage position 1'' is started.

Furthermore, when the arm operating lever 9a or the boom operating lever 9b is fully operated, the offset electromagnetic proportional valve 39 is turned on for automatic offset return, thereby starting automatic return to the storage position and returning to the reference position. At this point, the offset electromagnetic proportional valve 39 switches to neutral.

After the bucket 1 has returned to the offset reference position, either the arm operating lever 9a or the boom operating lever 9b
However, if the boat on the opposite side of the manually operated control valve is turned on to wait for bucket 1 to return to the offset reference position, the boat on the opposite side is turned on.
As FF, the boom 6 or arm 4 starts rotating again.

That is, when the bucket 1 is pulled up to the line of the prohibited offset area a shown in FIG. It stops and waits for bucket 1 to return to position 1'.

Conversely, until reaching the position of the offset prohibited area a, the operation of returning the bucket 1 to the reference position and the pulling operation of the boom 6 or arm 4 are performed in parallel.

FIG. 6 mainly shows a flowchart of shockless stop and stop control in a dangerous area.

As shown in the flowchart, a danger angle is determined for each of the boom 6, arm 4, and offset arm 22, and when each danger angle is reached by manual operation, either the boom electromagnetic proportional valve 37 or the arm electromagnetic proportional valve 38 is offset. The side of the electromagnetic proportional valve 39 opposite to the manually operated control valve is turned on, or the offset electromagnetic proportional valve 39 and the unload proportional valve 50 are turned on.
The unloading boat is turned on, and regardless of the operating position of the manual control valve, the expansion and contraction of each boom cylinder 5, offset cylinder 3, and arm cylinder 24 are stopped and a safe state is achieved.

That is, it is checked whether the bucket 1 is in the right offset state, and if it is in the right offset state and each offset is not a danger angle, the bucket 1 is moved to the cabin 2 without checking the rotational position of the boom 6 or the arm 4. Since there is no interference with the system, work can continue as is.

If the bucket 1 is offset to the left, check whether the angle of the boom 6 is below the danger angle or the angle of the arm 4 is below the danger angle, and if both are below the danger angle, Of the operating levers 9, it is checked whether the arm operating lever 9a or the boom operating lever 9b is being operated.

When the boom operation lever 9b is operated, the unload port B of the boom electromagnetic proportional valve 37 is turned on, and the rotation of the boom 6 is stopped.

Also, if the arm operating lever 9a is being operated, turn on the port on the opposite side of the arm electromagnetic proportional valve 38,
This stops the rotation of arm 4.

If both are being operated, the unload boat B of both the boom electromagnetic proportional valve 37 and the arm electromagnetic proportional valve 38 is turned on to stop their rotation.

The ON state of the boat on the opposite side continues as long as the lever operation continues, and when the lever operation stops, the B port becomes OFF.
It becomes FF.

As a result, when the bucket 1 approaches the dangerous area, the boom 6 and arm 4 stop rotating, and only when the bucket 1 returns to its reference position can it rotate below the dangerous angle.

(G) Effects of the Invention Since the present invention is configured as described above, it has the following effects.

First, an arm 4 is supported at the tip of a boom 6 that is pivotally supported on a rotating base 12 so as to be able to move up and down, and can be offset to left and right parallel positions, and the bucket 1 is scooped and rotated at the tip of the arm 4. In a configuration in which the bucket 1 can be stored on the side of the cabin 2 by folding the boom 6 and arm 4 when turning, the bucket 1 is automatically moved by operating the operating lever to the storage side. Since we automatically controlled the offset cylinder 3 to return it to the storage position, we forgot that we had offset the bucket 1 to the cabin 2 side and pulled the bucket 1 back to the storage position to move the bucket 1 to the cabin 2 side.
This eliminates the possibility of destroying the aircraft or injuring the operator in seat 8.

Second, by operating the operating lever toward the storage side of the bucket 1, the offset cylinder 3 is returned to the storage position and the bucket 1 is pulled toward the side of the boom 6 at the same time. Compared to waiting for the bucket 1 to return to the storage position from the offset state and then rotating the boom 6 or arm 4, it is possible to effectively pull the bucket 1 diagonally to the storage position. It was possible to perform the action quickly.

Thirdly, when the operator releases the operating lever 9 that operates the bucket 1 to the storage side, the electromagnetic proportional valve automatically stops at the bucket 1 position at that moment. From the ON state, A or B boat O
Since it is configured to return to the FF state, when the control lever 9 returns slightly from the full stroke position, the boom 6
Thus, the arm 4 can be stopped without shock.

Fourth, since the configuration is configured so that the offset movement starts automatically only when the bucket 1 rises above a certain height set by the height setting device, for example, steel sheet piles etc. protrude above the ground surface. By setting the height of the steel sheet pile using the bucket height setting switch 34, the steel sheet pile will start returning to the offset reference position after exceeding the specified position. There is no chance of knocking down or damaging bucket 1.

Fifth, buckets 1 of different widths can be selectively attached to the tip of the arm 4, and by replacing the bucket 1, the bucket storage position can be automatically changed, so when a narrow bucket 1 is used, Since the bucket 1 can be stored closer to the cabin 2 than the wide standard bucket 1, the turning radius of the backhoe can be made smaller.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the small swing type backhoe of the present invention, FIG. 2 is a side view of the same in a working state, and FIG. 3 is a bucket width recognition body 25 and a bucket sensor 26 that transmit a signal that the bucket 1 has been replaced. FIG. 4 is a diagram showing the sensor, controller 21, electromagnetic proportional valve 20, and operation panel 27 arranged in each part of the backhoe, FIG. 5 is a flowchart of automatic offset and shockless stopping operation, and FIG. The figure is a flowchart of shockless stopping and stopping in a dangerous area, FIG. 7 is a hydraulic circuit diagram of a small swing type backhoe, and FIG. 8 is a diagram showing the operating state of each electromagnetic valve. ■...Bucket 1"...Reference storage position 2...Cabin 3...Offset cylinder 4...Arm 5...Boom cylinder 6...Boom 7...Bucket cylinder 8... Seat 9...Operating lever 11...Crawler 2 traveling device a...Offset prohibited area Applicant Yanmar Diesel Co., Ltd. agent Patent attorney Yano Kotobuki Part procedure amendment, form. 1. Indication of the case 1988 Patent Application No. 100595 2, Name of the invention: Automatic offset mechanism for small swing type backhoe 3, Relationship to the case of the person making the amendment Applicant address: 1-32 Chayamachi, Kita-ku, Osaka Name (67)
8) Yanmar Diesel Co., Ltd. Representative Atsushi Yamaoka
Male (0 others) 4. Agent address: Nagahori Yachiyo Building, 1-11-9 Minamisenba, Minami-ku, Osaka July 6, 1988 (Delivery date: July 26, 1988)
6. Drawings to be amended (Figures 5 and 6) 7. Details of the amendment We will submit the revised drawings Figures 5 and 6 as shown in the attached sheet.

Claims (5)

[Claims] (1) An arm 4 is supported at the tip of a boom 6 that is pivotably supported on a swivel table 12 so as to be able to move up and down, and can be offset to left and right parallel positions, and the bucket 1 is scooped up and rotated at the tip of the arm 4. In a configuration in which the bucket 1 can be stored on the side of the cabin 2 by folding the boom 6 and arm 4 when turning, the bucket 1 is automatically moved by operating the operating lever to the storage side. An automatic offset mechanism for a small swing type backhoe, characterized in that it is configured to return to a stored position. (2) The system is characterized in that by operating the operating lever toward the storage side of the bucket 1, the operation of returning the offset cylinder 3 to the storage position and the operation of drawing the bucket 1 to the side of the boom 6 are performed at the same time. An automatic offset mechanism for a small swing type backhoe according to claim 1. (3) When the operator releases his hand from the fully rotated position of the operating lever 9 that operates the bucket 1 to the storage side,
2. The automatic offset mechanism for a small swing type backhoe according to claim 1, wherein the automatic offset mechanism is configured to arbitrarily stop the bucket at the instantaneous position of the bucket. (4) Claim 1 is characterized in that the bucket 1 is configured to automatically start offset movement only when it rises above a certain height set by a height setting device. Automatic offset mechanism for small swing type backhoe. (5) It is possible to selectively attach buckets 1 of different widths to the tip of the arm 4, and by replacing the bucket 1, the bucket storage position can be automatically changed. Automatic offset mechanism of the small swing type backhoe described.