JP2574386B2 - Automatic offset mechanism for small turning backhoe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial application field The present invention relates to a backhoe device in which a bucket, an arm and a boom are bent in a state where a bucket is stored and a turning radius of a swivel table is reduced as much as possible. In a configuration that can be stored in a state where it is located inside the swivel table in a plan view, the arm of the small swing type backhoe is further offset to a position parallel to the traveling direction left and right to facilitate excavation of gutters This is related to a mechanism that has made it possible.

(B) Conventional technology Conventionally, in a backhoe, a technology for stopping an arm when the arm is approached by a certain amount or more and put in a dangerous state is known. For example,
It is as in JP 12926.

Further, a technique for offsetting the arm of the backhoe and the bucket to a position parallel to the traveling direction is also known. For example, Japanese Utility Model Laid-Open No. 63-9361 and Japanese Patent Publication No. 40-20879.

(C) Problems to be Solved by the Invention According to the present invention, the bucket can be stored in the side of the cabin so that the swivel table can be swiveled even in a particularly narrow space, and furthermore, the bucket and the arm are moved right and left in the traveling direction When the bucket 1 is returned to the working position again from the state where the bucket is stored in a safe position beside the cabin when the offset is possible in a parallel state to the The operation of performing work after setting the offset position is repeated as “excavation → bucket storage → turning → bucket protrusion → earth removal → bucket storage → rotation → bucket protrusion → excavation”, and the operation of projecting and storing repeatedly. Each time, the bucket is pushed to the working position without adjusting the offset pedal 29 to determine the offset position. When the bucket is issued, the bucket is automatically moved to the set offset position.

Further, if the operation of returning the bucket to the working position and the operation of operating the lever to protrude and rotate the arm or the boom by the operator can be separately operated, it takes time to move the bucket to the set position. Therefore, the operation of projecting the bucket by the operation lever and the operation of returning the bucket to the storage position by automatic control can be performed in parallel.

Also, if the operator releases the hand from the state in which the operation lever is fully operated to move the bucket to the work position, it is possible that a dangerous situation may occur. The operation of returning to the storage position is also configured to stop at that position.

In addition, when the returning operation from the offset position to the setting work position is started immediately in conjunction with the protruding operation of the bucket, the position where the bucket is close to the ground surface and a steel sheet pile or the like stands on the side. Automatic offset is started from, and it is dangerous that the bucket is destroyed or the ropes fall down, so a height setting device is provided, and when the control of the automatic offset return to the working position becomes less than the set value, Is configured so that automatic offset cannot be performed.

In addition, as for the bucket attached to the tip of the arm, it is usual to prepare several types of buckets 1 having different widths. When the storage position is set with a narrow width bucket, a wide width bucket is attached. Then, when the bucket 1 is moved, the bucket may be greatly offset from the set position, so that the work setting position of the bucket can be automatically changed with the replacement of the bucket.

(D) Means for Solving the Problem The object of the present invention is as described above, and a configuration for achieving the object will be described below.

An arm 4 is supported at the tip of a boom 6 pivotally supported on the swivel table 12 so as to be vertically rotatable so that the arm 4 can be offset to the left and right parallel positions. When the boom 6 and the arm 4 are folded and the bucket 1 can be stored on the side of the cabin 2 at the time of turning, the arm angle or the boom angle is adjusted by operating the arm operating lever 9a or the boom operating lever 9b to the working side. Is configured to automatically offset the bucket 1 to the set position at a position where the angle becomes equal to or larger than a predetermined angle, and the offset operation of the offset arm 22 to the set work position and the setting of the arm 4 or the boom 6 are performed. The bucket 1 is configured to simultaneously perform a pivoting operation to a work position and to move obliquely a linear distance to a protrusion setting position.

As another embodiment, in the operation of the arm operation lever 9a or the boom operation lever 9b to the working side, when the operator releases his / her hand from the full rotation position of the operation lever 9, the position of the bucket 1 at that moment is changed. It is configured to stop arbitrarily.

In another embodiment, when the bucket 1 descends to a certain height set by the height setting device, the automatic offset to the set position is stopped.

In another embodiment, buckets 1 having different widths can be selectively mounted at the tip of the arm 4, and the bucket setting position at the time of work can be automatically changed by exchanging the buckets 1.

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

FIG. 1 is a plan view of a small turning type backhoe according to the present invention, and FIG.
The figure is a side view of the same working state, FIG. 3 is a block diagram showing a control mechanism, and FIG.
FIG. 5 is a perspective view showing a portion 26, and FIG. 5 is a flowchart of the offset control mechanism of the present invention.

In the backhoe, a swivel table bearing 13 is arranged on a crawler-type traveling device 11 in which a discharge plate 10 is arranged at a rear portion, and a swivel table 12 is arranged on the swivel table bearing 13. The turntable 12 is 360
This enables horizontal rotation.

In addition, the cabin 2 is arranged in the left half on the swivel table 12,
The engine and balance weight are mounted on the rear,
The base of the boom 6 is pivotally supported at substantially the center of the position 12 so as to be vertically rotatable.

The boom cylinder 5 is arranged between the boom 6 and the swivel base 12, and the boom 6 is configured to be rotatable up and down by expansion and contraction of the boom cylinder 5.

An offset arm 22 and a parallel link 23 are arranged at the tip of the boom 6, and the offset cylinder 3 is interposed between the offset arm 22 and the boom 6. The expansion and contraction of the offset cylinder 3 causes the offset arm 22 and the parallel link 23 to rotate left and right, and the arm 4 supported at the tip thereof is offset in the left and right parallel state.

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

Further, the bucket 1 is pivotally supported at the tip of the arm 4, and the bucket 1 can be scooped and rotated by a bucket cylinder 7.

In the overall configuration as described above, as shown in FIG. 3, a boom sensor 15 for detecting the rotation angle of the boom 6 is arranged at the base of the boom 6 by a potentiometer or the like, and is provided with an offset arm. An offset sensor 16 for detecting the left and right offset angle of the arm 22 is provided at the base of the parallel link 23 by a potentiometer, and an arm sensor 17 for detecting the rotation angle of the arm A is provided at the tip of the arm 4 of the offset arm 22. It is located at the pivot.

A lever sensor 14 for detecting that the operation lever 9 has been operated to rotate the boom 6 and the arm A is disposed at the base of the operation lever 9 composed of the arm operation lever 9a and the boom operation lever 9b. It is. An offset pedal 29 for directly operating an offset of the arm 4 by an operator is disposed below the operation lever 9, and an offset pedal sensor 28 is disposed at a base of the offset pedal 29.

The electromagnetic proportional valve 20 is interposed in the oil supply path of the boom cylinder 5, the arm cylinder 24, and the offset cylinder 3, and performs a shockless stop.

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

Inside the controller 21, an analog / digital conversion circuit A / D described in the lower part of FIG.
In addition, an interface I / O, a buffer circuit, a drive circuit, etc., a discrete circuit, a light bulb cutoff circuit, and a power supply circuit are arranged to perform a control operation.

In FIG. 3, an ultrasonic sensor 19 and a touch sensor 18 are attached to the front and side portions of the cabin 2.
When the automatic control goes out of control and the bucket 1 approaches the position where it contacts the cabin 2, a double safety device is configured to stop the attraction of the bucket 1 to the storage position and to issue an alarm. -ing

As shown in FIG. 5, when the bucket 1 is replaced, a bucket sensor 26 is disposed at the tip of the arm 4 to automatically change the bucket width, and the arm 4 is provided for each bucket 1. By changing the width recognition body 25, it is configured to switch.

The bucket width recognition body 25 may be made of a magnetic material.

Further, a boom electromagnetic proportional valve 37, an arm electromagnetic proportional valve 38, an offset electromagnetic proportional valve 39, and a swing electromagnetic proportional valve 51 shown in FIG.
Is disposed at the lower portion of the swivel 12.

(F) Operation of the Invention The configuration of the automatic offset mechanism of the small turning type backhoe of the present invention is as described above. Next, the operation of the present invention will be described with reference to the sixth control flowchart.

In the automatic offset mechanism of the small turning backhoe according to the present invention, when the bucket 1 is returned from the working state to the retracted position, the offset pedal 29 is operated by operating the arm operating lever 9a and the boom operating lever 9b.
, The offset cylinder 3 automatically expands and contracts automatically, and the bucket 1 is controlled to be at the storage reference position 1 ".

In the present invention, in addition to the automatic offset control at the time of storage, the automatic return to the set position is also performed at the time of projecting to the excavation work position.

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

At the same time, the circuit power of the controller 21 and the solenoid valve case 20 is turned on.

Next, it is checked whether the operation of the potentiometers constituting the angle sensors of each part is normal, and if the potentiometer is abnormal in the automatic control state,
The alarm lamp 30 and the alarm buzzer 31 on the operation panel 27 are turned on to notify the operator of danger.

Next, it is checked whether the width of the bucket 1 is standard. Whether the bucket 1 is standard or wide is input by a bucket width switch 33 constituted by a non-locking push-in switch. In a normal automatic start state, the bucket 1 is set in the wide bucket 1. When the bucket width switch 33 is depressed in the case of a standard bucket, control is started so that the reference storage position 1 "of the bucket 1 is set to the position closest to the cabin 2 similarly to the wide bucket. It is.

Also, when the bucket 1 of the present invention is projected to the set work position, the projected position is corrected.

Next, it is checked whether or not the automatic offset possible height is set by the bucket height setting switch 34.

The bucket height setting switch 34 is configured as a rotary switch, and performs offset control below the minimum height.
There is also a position where the automatic switch 35 is turned off.
If not, the offset is offset pedal 29
Is performed under the intentional operation of the operator.

When the automatic switch 35 is ON and the bucket height setting switch 34 is OFF, a danger display by the ultrasonic sensor 19 or the touch sensor 18 or a shockless stop of the boom 6, the arm 4, or the offset arm 22, etc. Is performed, but offset control is not performed.

In this state, the automatic offset control when the bucket 1 is stored is performed, and the bucket 1 is always stored in the reference storage position 1 "beside the cabin 2. In addition to the automatic storage control, the automatic projection control If it is desired to perform the control, the control is performed according to the flowchart as shown in FIG.

That is, when the extruding position automatic return switch 50 provided on the operation box 27 is turned on at the same time as the start of the excavation work, as shown in the right drawing of FIG.
O is stored. Further, the turning angle θO of the turning table 12 is also stored.

In this state, sediment is scooped by the bucket 1, the bucket 1 is temporarily stored in the side of the cabin 2, manually turned in the direction of the truck bed, and the bucket 1 is discharged on the cargo bed. Then, the swivel table 12 is manually swung in the storage state on the side of the vehicle to return to the original excavation position.

When the arm operating lever 9a or the boom operating lever 9b is fully rotated at the returned position and the bucket 1 is moved to the projecting position at the time of work, the rotated position of the boom 6 and the arm 4 becomes the position. Even if the offset of the bucket 1 is started, it is checked that the area does not interfere with the cabin 2, that is, the area is outside the offset prohibited area a in FIG.

When the boom 6 and the arm 4 are sufficiently out of the offset prohibition area a, the offset solenoid proportional valve 39 is turned ON for the first time, and the offset cylinder 3 is moved to the position of the set rotation angle δO of the offset arm 22 described above. to shrink.

The offset operation and the pivoting operation of the boom 6 or the arm 4 can be simultaneously performed, and are configured to move obliquely by a linear distance and to move to the projecting set position.

When the bucket 1 reaches the set position of the turning angle δO, the offset electromagnetic proportional valve 39 is turned off. Next, it is checked whether or not the position of the turntable 12 is at the set position of the turning angle θO. If it is deviated from the position, the turning electromagnetic proportional valve 51 is operated to match this position.

When the set swing angle θO is reached, the swing solenoid proportional valve 51 is
Turn it off.

When the rotation operation of the boom 6 and the arm 4 is started,
First, it is checked whether the boom operation lever 9b or the arm operation lever 9a is fully operated.

When one of the operation levers 9 is fully operated by the operator, the boom electromagnetic proportional valve 37 or the arm electromagnetic proportional valve 38 can supply pressure oil to the oil passage controlled by the manual control valve. However, when the operator grips one of the operation levers 9 and returns the lever from the full operation state to the neutral position, the oil passage by the manually operated valve is switched to rotate. Attempts to stop, but the boom solenoid proportional valve 37 or arm solenoid proportional valve
Because of the intervention of 38, it stops in a shockless state by operating the proportional valve.

That is, although the arm electromagnetic proportional valve 38 or the boom electromagnetic proportional valve 37 has been able to supply oil by turning on the solenoid, the arm operating lever 9a or the boom operating lever 9b has been used.
When the valve is returned from the full rotation position to the neutral position, the proportional valve returns to the neutral position at a constant speed and stops in a shockless state.

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

First, an arm 4 is supported at the tip of a boom 6 pivotally supported on the swivel table 12 so as to be vertically rotatable so that the arm 4 can be offset to the left and right parallel positions. At the time of turning, the boom 6 and the arm 4
Is folded so that the bucket 1 can be stored on the side of the cabin 2, the bucket 1 is stored in the reference storage position 1 ”, and the bucket 1 is projected to the working position again after turning → discharging → storing → turning. Since the offset can be automatically performed, the operation of the offset pedal 29 for the offset operation can be omitted, and the operation of the operator can be reduced.

Second, by operating the operation lever to the work position of the bucket 1, the operation of returning the offset arm 22 to the set position and the operation of projecting the bucket 1 forward are simultaneously performed. Can be projected obliquely to the set position, so that the shortest distance can be moved and the projecting operation can be performed quickly.

Third, when the operator releases the operation lever 9 for operating the bucket 1 on the protruding side, an electromagnetic proportional valve is configured to stop arbitrarily at the instantaneous bucket 1 position. The automatic offset operation can be stopped at a position slightly returned from the stroke position. Thus, priority can be given to manual operation, and safety can be ensured.

Fourth, since the bucket 1 is configured to start offset movement automatically only at a position equal to or higher than a certain height set by the height setting device, for example, a sheet pile or the like is projected above the ground surface. When working in the position, the height of the sheet pile is set by the bucket height setting switch 34, so that the sheet is returned to the offset setting position only above the position, so that the sheet pile is tilted or It does not hurt 1.

Fifth, buckets 1 having different widths can be selectively mounted at the tip of the arm 4 and the bucket storage position can be automatically changed by exchanging the buckets 1. The operator-set width can be corrected for each bucket 1 width.

[Brief description of the drawings]

1 is a plan view of a small turning backhoe of the present invention, FIG. 2 is a side view of the same working state, FIG. 3 is a block diagram showing a control mechanism, and FIG.
FIG. 5 is a flowchart of the offset control mechanism of the present invention. DESCRIPTION OF SYMBOLS 1 ... Bucket 2 ... Cabin 3 ... Offset cylinder 4 ... Arm 5 ... Boom cylinder 6 ... Boom 7 ... Bucket cylinder 8 ... Seat 9 ... Operation lever 11 ... Crawler type traveling device

Claims (4)

(57) [Claims] An arm (4) is supported at the tip of a boom (6) pivotally supported on a swivel table (12) so that it can be offset to left and right parallel positions, and the tip of the arm (4) scoops the bucket (1). In a configuration in which the boom 6 and the arm 4 are folded and the bucket 1 can be stored on the side of the cabin 2 at the time of turning, by operating the arm operation lever 9a or the boom operation lever 9b to the working side, At a position where the arm angle or the boom angle is equal to or larger than a predetermined angle, the bucket 1 is automatically offset to the set position, and the offset operation of the offset arm 22 to the set work position, the arm 4 or the boom 6, wherein the bucket 1 is simultaneously rotated to the set work position, and the bucket 1 is configured to move obliquely and linearly to the set protrusion position. Automatic offset mechanism of the backhoe. 2. In the operation of the arm operating lever 9a or the boom operating lever 9b toward the working side, when the operator releases his / her hand from the full rotation position of the operating lever 9, the position of the bucket 1 at that moment is arbitrarily determined. 2. An automatic offset mechanism for a small turning backhoe according to claim 1, wherein said automatic turning mechanism is configured to stop. 3. The apparatus according to claim 1, wherein when the bucket is lowered to a predetermined height set by a height setting device, automatic offset to a set position is stopped. Automatic offset mechanism of the small swivel type backhoe described in the paragraph. 4. A bucket 1 having a different width can be selectively mounted on the tip of the arm 4, and the bucket setting position at the time of work can be automatically changed by replacing the bucket 1. 2. An automatic offset mechanism for a small turning backhoe according to claim 1.