JPH01271536A - Dangerous area avoiding device for work machine - Google Patents

Abstract

PURPOSE:To ensure safety of an operator, even when misoperation is generated, by automatically stopping turning a boom, arm and an offset arm when an excavator reaches the periphery of a cabin. CONSTITUTION:A boom 6, arm 4 and a bucket 1 are stored in a turn bed 12 in its circle in the sideward of a cabin 2, and its periphery is set to a dangerous area. When an excavator reaches the periphery of the cabin 2, the excavator is sensed approaching by an ultrasonic sensor serving as the contactless sensor and by a touch sensor serving as the contact sensor, and a turning motion of the boom 6, arm 4 and an offset arm 22 is automatically stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial Application Field The present invention is a backhoe configured so that when the boom, arm, and bucket are stored, they are stored inside the turning circle of the turning base, Furthermore, the present invention relates to a technique in which the arm portion of the structure can be offset by moving parallel to the boom from side to side.

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

For example, see Utility Model Publication No. 58-12926.

There is also a known technique in which the arms of the backhoe are offset to horizontal and parallel positions with respect to the boom.

For example, Japanese Patent Publication No. 40-208.79.

(C) Problems to be Solved by the Invention In the present invention, the arm is movable off-center with respect to the boom, and the bucket is stored in a stored state immediately to the side of the cabin, so that the operator can If care is not taken, if the bucket is pulled while still offset, it will interfere with the cabin and create a dangerous situation for the operator.

In the present invention, in order to ensure the minimum safety, when the bucket approaches the cabin, the cabin 2 is stopped in order to stop the rotation of the boom or arm.
A non-contact sensor and a contact sensor are placed side by side surrounding the hazardous area around the area.

In addition, in the event that these safety devices become ineffective due to failure of the sensors that detect automatic stop in the dangerous area or runaway of the CPU, a discrete system that is activated by abnormal signals from these electric circuits is used as a double safety device. A circuit was installed to cut off the power to the electromagnetic proportional valve and stop the movement of each part.

(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 movable up and down in a vertically movable manner, and is rotatably attached to the tip of the arm 4 to scoop up a bucket 1. , in a configuration in which the boom 6 and arm 4 are folded and the bucket 1 can be stored on the side of the cabin 2 when turning, a non-contact system detects when the bucket 1 approaches a dangerous area around the cabin 2. A sensor and a contact sensor that detects that the bucket 1 has contacted the cabin 2 are placed side by side, and when both sensors detect the bucket 1, etc., a solenoid valve that controls the drive of the boom 6, arm 4, and offset arm 22 is activated. It is configured to stop.

In another embodiment, a discrete circuit 53 that inputs signals from a non-contact sensor and a contact sensor is interposed, and the discrete circuit stops the solenoid valve when a signal of -a certain level or higher is input due to an abnormality of the sensor. 53
It is an intervening device.

(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 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 perspective view of the portion shown in FIG. 4, which shows the sensors, controller 21, electromagnetic proportional valve 20, and operation box 27 arranged in each part of the backhoe.

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 6 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 off-center angle of the offset arm 22, and an arm sensor 17 that detects the rotation angle of the arm 4 is arranged at the base of the parallel link 23. It is arranged at the tip and the pivot point of the 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 controlling 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 performs automatic control and shockless stopping.

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, and a power supply. Circuits are arranged to perform control operations.

Further, in FIG. 4, an ultrasonic sensor 19 as a non-contact sensor and a touch sensor 18 as a contact sensor are attached to the upper part of the cabin 2, as well as a boom sensor 15, an offset sensor 16, and an arm sensor 17.
If the safety device constructed by the above becomes ineffective due to runaway of the central processing circuit CPU, and the bucket 1 approaches the position where it touches the cabin 2, it stops pulling the bucket 1 to the storage position and issues an alarm. Double・
This constitutes a triple safety device.

Further, as shown in FIG. 3, a bucket sensor 26 is disposed at the tip of the arm 4 in order to automatically change the bucket width when the bucket 1 is replaced. The bucket width recognition body 25 is configured to be switched by changing the bucket width recognition body 25 provided in the bucket width recognition body 25. The bucket width recognition body 25 may be made of a magnetic material.

FIG. 7 shows a hydraulic circuit diagram constituting the dangerous area avoidance device for a working machine according to the present invention, in which each manually operated control valve operates the pressure oil to the boom cylinder 5, arm cylinder 24, and offset cylinder 3. The control valve and the electromagnetic proportional valve are interposed in tandem from the pump P side.

The manually operated control valve and the electromagnetic proportional valve have approximately the same boat configuration, and the manually operated control valve has a raised boat of 1-U.
On the side of , the solenoid proportional valve is also closed on the raising side, A bow 1-, and when the manually operated control valve is on the lowering bow 1-D, the lowering boat D is set as the lowering side B boat.

A lamp circuit, which is a special microcomputer circuit, is installed in the opening and closing of the electromagnetic proportional valve, and the voltage gradually rises and falls during opening and closing, and the flow of pressure oil changes proportionally, allowing the movement of the drive to stop. It is configured to be in a shockless state.

When the area is outside the danger area, the electromagnetic proportional valve also opens and closes in the direction of rotation of the operating lever 9, thereby constructing a shockless mechanism. The operation of automatically stopping the movement of the boom 6, arm 4, and offset without turning is performed by automatically operating the solenoid proportional valve in the opposite direction of the manually operated control valve. The boom 6
The structure is such that the rotation of the arm 4 and the offset arm 22 is automatically stopped in a shockless state.

(F) Function of the Invention The structure of the small swing type backhoe of the present invention is as described above, and next, according to the control flowcharts of FIGS. 5 and 6,
A detailed explanation of the present invention will be given below.

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, a check is made to see if the potentiometers that make up the angle sensors in each part are operating normally, and if there is an abnormality in the potentiometers under automatic control, the alarm lamp 30 on the operation panel 27 and the alarm Buzzer 31 is O
N, which alerts the operator to the danger.

Next, it is checked whether the width of bucket 1 is standard. Whether the bucket 1 is standard or narrow is input using the bucket width switch 33, which is a non-locking push-in switch. Ori,
If the bucket width switch 33 is pressed when changing to a narrow bucket, control is started so that the bucket 1 is stored at the narrowest position closest to the cabin 2.

Even if the width is changed to narrow, if the bucket width switch 33 is set to the normal 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, automatic offset control is not performed.

When excavation work is started and the rotation operation of the boom 6, arm 4, or offset arm 22 is started, it is first checked whether the boom operation lever 9b or the arm operation lever 9a is fully operated.

When either of the operating levers 9 is fully operated by the operator, the A boat side or the B port of the boom solenoid proportional valve 37 or the arm solenoid proportional valve 38 is turned on, and each boom cylinder 5 and arm cylinder 24 are turned on. In addition, 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 FIG.

This causes the boom 6 or the arm 4 to start rotating in the direction operated by the operating lever 9, but if the operator grasps either operating lever 9 and returns the lever even slightly from the fully operated state. , the boom electromagnetic proportional valve 37 or the arm electromagnetic proportional valve 38 senses this first before the oil passage is switched by the manual operation control valve and the rotation stops.
The state of the A port or B boat returns to the neutral position, and the control by this electromagnetic proportional valve has priority, so the oil amount is gradually adjusted by operating the proportional valve, and the engine is stopped in a shockless state.

That is, until then, the arm electromagnetic proportional valve 38 or the boom electromagnetic proportional valve 37 was switched to the A port or B boat side by turning on the solenoid, but when the operating lever 9 started rotating, it was switched to the A port side or the B port side. The solenoid on the side is turned off, and the proportional valve is activated to gradually stop the engine. After a slight delay, the manually operated control valve is also turned off and stopped.

Also, when either control lever 9 is fully operated, the boom 6
Check whether the bucket 1 is in a dangerous position on the left or right where it will interfere with the cabin 2 if the bucket 1 is rotated and the arm 4 is in a rotating state, and if the offset position is in the dangerous area around the cabin 2. In case, the boom solenoid proportional valve 37 or the arm solenoid proportional valve 38 is connected to the B boat side or the A port side of the boat opposite to the manually operated control valve.
N, the oil from the manually operated control valve is guided to the tank side, and is turned off in a shockless state, stopping the rotation of the boom 6 and arm 4 until the offset position returns to the safe position.

Furthermore, when approaching the offset prohibited area a for automatic offset control, the boom solenoid proportional valve 37 and the arm solenoid proportional valve 38 are switched to the B boat side to stop their rotation, and the offset solenoid proportional valve 39 is stopped. Only as ON state,
The bucket 1 is returned to its standard position where it can be stored.

Next, the height of the bucket 1 is checked and set by the bucket height setting switch 34. Only when the height is equal to or higher than the tip height, 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 B or boat A on the opposite side of the manual operation control valve is turned on in order to wait for bucket 1 to return to the offset reference position, turn off the boat on the opposite side. Then, 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 the 1'' position.

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 stop control in a dangerous area, which is the main part of the present invention. In particular, the automatic stop in this dangerous area works effectively when the off-cent automatic control is turned OFF and the manual scooping and
In this case, the automatic offset control will not work even if bucket 1 approaches, but there is also a danger in this case, so each sensor detects the surroundings of cabin 2. A safety device is constructed in case the bucket 1 approaches the dangerous area.

As shown in the flowchart, the danger angle is determined for each of the boom 6, arm 4, and offset arm 22, and if the danger angle for each arm is below the danger angle, the boom electromagnetic proportional valve 37 switches the arm electromagnetic proportional The boat on the opposite side of the valve 38 from the manually operated control valve is turned on, and regardless of the operating position of the manually operated control valve, the expansion and contraction of the boom cylinder 5 and the arm cylinder 24 are stopped and a safe state is obtained. It is.

That is, it is checked whether the bucket 1 is in the right offset state, and if it is in the right offset state, the bucket 1 is moved without checking the rotational position of the boom 6 or arm 4.
1 does not interfere with cabin 2, so work can continue as is.

If bucket 1 is offset to the left, check whether the angle of boom 6 is below the danger angle, but the angle of arm 4 is below the danger angle, and if both are below the danger angle, check whether the angle of arm 4 is 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 boat on the side opposite to the manual operation control valve of the boom electromagnetic proportional valve 37 is turned on, and the rotation of the boom 6 is stopped.

Further, if the arm operating lever 9a is being operated, the boat on the side opposite to the manually operated control valve of the arm electromagnetic proportional valve 38 is turned on to stop the rotation of the arm 4.

In addition, if both of the boom electromagnetic proportional valve 37 and the arm electromagnetic proportional valve 38 are operated, the boats on the side opposite to the manually operated valve are turned on and rotation is stopped.

The boat on the opposite side of the manual operation valve remains ON as long as the lever operation continues, and when the lever operation stops, the boat on the opposite side of the manual operation valve turns OFF.

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

In addition, the offset arm 22 is operated by the offset pedal 29.
When the offset angle is operated, it is determined whether this offset angle is in the dangerous range and the off-cent solenoid proportional valve 39 is operated.
It will automatically stop for safety reasons. In this case as well, the offset electromagnetic proportional valve 39 provides a shockless stop.

Fig. 8 is a block diagram of dangerous area avoidance control of the working machine of the present invention, Figs. 9 and 10 are front and side views of the state in which an ultrasonic sensor is attached as a triple safety device, and Fig. 11 The figure is a perspective view of the cabin 2 with a touch sensor attached thereto.

In the backhoe of the present invention, the boom sensor 15
A safety device based on the determination of dangerous areas by sensors such as the offset sensor 16 and arm sensor 17 and stopping by an electromagnetic proportional valve, and a discrete circuit 53 that prevents danger due to sensor failure. An ultrasonic sensor is placed as a non-contact sensor, and a touch sensor is placed side by side as a contact sensor.

That is, a front ultrasonic sensor 19b, a side ultrasonic sensor 19a, and a top ultrasonic sensor 19c are provided, and the electromagnetic proportional valve is configured to stop when the bucket 1 reaches within the detection range of the ultrasonic sensors. .

In addition, the touch sensor 18 is placed in parallel with the ultrasonic sensor 19.
This provides a fifth safety device.

That is, the touch sensor 18 also includes a side touch sensor 18b, a front touch sensor 18c, and a top touch sensor 18a.
are attached to each part of cabin 2, and bucket 1 is attached to these parts.
When they come into contact, the electromagnetic proportional valves stop the movement of each part.

Further, signals from the touch sensor 18 and the ultrasonic sensor 19 are passed through the discrete circuit 53,
If an abnormality occurs in these sensors or the power to the safety circuit is turned off and the safety circuit no longer operates, the electromagnetic proportional valve will be stopped so that the bucket 1 will stop at the safe position. It consists of three safety devices and six safety devices.

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

First, move the boom 6, arm 4, and bucket 1 to the cabin 2.
In a backhoe that enables small turning work by storing the arm in the circle of the swivel base 12 on the side of the boom 6, when the arm is further moved parallel to the boom 6 to enable offset, the offset However, in the case of the present invention, the area around the cabin 2 is configured as a dangerous area, and the excavation rig is pulled toward the cabin 2 side, creating a dangerous situation for the operator. When the excavator reaches the excavator, the ultrasonic sensor 19, which is a non-contact sensor, and the touch sensor 18, which is a contact sensor, detect the proximity of the excavation equipment and automatically stop the rotation of the boom 6, arm 4, and offset arm 22. The system is designed to ensure the safety of the operator even if an operational error occurs.

Second, an ultrasonic sensor 19 which is the contact sensor,
If an abnormality occurs in the touch sensor 18, which is a contact sensor, or if the sensor's power is turned off, the safety circuit will not operate, but in this case, the discrete circuit 53 will detect this. Since the power supply cutoff circuit 52 is configured to cut off the circuit of the electromagnetic proportional valve device 20, multiple safety devices can be constructed and the safety of the operator can be ensured.

[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 box 27 arranged in each part of the backhoe, FIG. 5 is a flowchart of automatic off-cent and shockless stop operation, and FIG. The figure is a flowchart of shockless and stopping in a dangerous area, Fig. 7 is a hydraulic circuit diagram of a small swing backhoe, Fig. 8 is a block diagram of dangerous area avoidance control of the working machine of the present invention, and Fig. 9. Figure 10 shows the front and side views of the triple safety device with the ultrasonic sensor attached, and Figure 11 shows the triple safety device.
The figure also shows cabin 2 with a touch sensor attached.
FIG. 1... Bucket 3... Offset cylinder 4... Arm 5... Boom cylinder 6... Boom 9a... Arm operating lever 9b... Boom operating lever 18... Touch sensor 19... Super Sonic sensor 52... Power cutoff circuit 53... Discrete circuit Figure 9 Figure 10 120° Procedure amendment, method, 1. Indication of the case 1986 Patent Application No. 100600 2 Name of the invention Hazardous area avoidance device for work equipment 3 Person making the amendment Relationship to the case Applicant Address 1-32 Chayamachi, Kita-ku, Osaka Name (67
B) Yanmar Diesel Co., Ltd. Representative Atsushi Yamaoka
Male (2 others) 4. Agent address: Nagahori Yachiyo Building, 1-11-9 Minamisenba, Minami-ku, Osaka July 6, 1988 (all date of delivery: July 26, 1988)
B) 6. Drawings subject to correction (Figures 5 and 6) 7. Contents of correction

Claims (2)

[Claims] (1) An arm 4 is supported at the tip of a boom 6 which is pivotably supported on a swivel table 12 so as to be able to move up and down, so that it 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 the arm 4 when turning, the dangerous area around the cabin 2 is
a non-contact sensor that detects when a drilling rig approaches;
A contact sensor that detects when the excavation equipment contacts the cabin 2 is placed side by side, and when both sensors detect the excavation equipment, the solenoid valve that controls the drive of the boom 6, the arm 4, and the offset arm 22 is stopped. A dangerous area avoidance device for a work machine, which is characterized by: (2) A discrete circuit 53 is installed that inputs signals from a non-contact sensor and a contact sensor, and a discrete circuit 53 is installed that stops the solenoid valve when a signal of a certain level or higher is input due to an abnormality in the sensor. A dangerous area avoidance device for a working machine according to claim 1, characterized in that: