JPH03208923A - Operation height limiting device - Google Patents

Abstract

PURPOSE:To prevent a collision by decelerating an operation speed when a part in the highest position of a work machine reaches the limit boundary between a safety area and a semi-danger area, and stopping when the part reaches the limit boundary between the semi-danger area and danger area. CONSTITUTION:A danger area A is set to the upper position of a hydraulic shovel 1, a semi-danger area B is set to the lower part of the area A, and a safety area C is set to the lower part of the area B. Potentiometers for boom, off-set and arm are mounted to each of pin connection sections of a rear arm, a front boom and arm of a work machine 4, and a detection signal is inputted to a controller of an operation height limiting device. When a part in the highest position among each of end positions of the work machine 4 reaches the limits boundary between the area C and area B, an operation speed of the work machine 4 is decelerated by the controller, and when the part reaches the limits boundary between the area B and area C, the work machine 4 is stopped by the controller.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a working height limiting device for a working machine installed mainly on a construction machine such as a hydraulic excavator.

In a conventional hydraulic excavator, a boom is attached to the front part of an upper revolving structure, and an arm and a packet (work tool) are sequentially connected to the tip of the boom to form a working machine. Excavation and loading work is performed by controlling the bending movement of the above-mentioned work equipment. Furthermore, many hydraulic excavators are equipped with a trench digging boom as the work equipment boom.

Problems to be Solved by the Invention When a hydraulic excavator performs work, there are obstacles above it, such as electric wires when outdoors, and ceilings when indoors. Packet for that purpose. Arms, booms, and other parts sometimes came into contact with or caught on the obstacles. This accident caused damage to objects it came into contact with and also caused disaster for the driver.

SUMMARY OF THE INVENTION An object of the present invention is to provide a working height limiting device for a hydraulic excavator working machine that can solve the above-mentioned problems and prevent accidental contact with obstacles above.

Means for Solving the Problems The means of this invention taken to solve the above problems are: (1) A. A dangerous area is placed above the construction machine in the vertical direction.
Also, a semi-dangerous area is set below the dangerous area, and a safety area is set below the semi-dangerous area, b. When the highest point of each tip of the above-mentioned work equipment reaches the boundary surface between the safe area and the semi-dangerous area during a lifting operation, the operating speed of the work equipment is decelerated, and The system is configured to stop the operation of the work equipment when it reaches the boundary between the area and the dangerous area. <2> A. In the working height limiting device according to claim 1, there is a lower boundary surface of the dangerous zone at a position slightly below the boundary surface between the dangerous zone and the semi-dangerous zone, and a boundary surface between the semi-dangerous zone and the safe zone. A semi-dangerous area lower boundary is set at a position slightly below the area boundary. When the highest point of each end of the work equipment reaches the above position or the boundary surface between the dangerous area and the semi-dangerous area during the lowering operation, it continues to pass through that operating state and the above dangerous area is reached. When it reaches the lower boundary surface of the area, it returns to the deceleration speed of the deceleration processing state described above, and when it reaches the area boundary surface between the semi-dangerous region and the safe region, it continues to pass through the deceleration processing state described above, and returns to the deceleration speed of the above-mentioned semi-dangerous region. It was arranged to return to normal operating speed when it reached the lower boundary surface.

(3) A. The working height limiting device according to claim 1 or claim 2, a display means for displaying the highest position among the respective tip positions of the working machine, and a setting means for setting a danger area;
A stop processing canceling means is provided for canceling the stop processing when the work machine is in the stop processing state.

Effect (1) a. Movement of the working machine is detected by the bending motion detection means, and a detection signal thereof is input to the controller. The controller makes a judgment based on the above detection signal, and when the highest part of the tip of the work equipment reaches the boundary surface between the safe area and the semi-dangerous area during the lifting operation, the controller sends the hydraulic pump regulator. A command signal is output to the evening electromagnetic proportional valve. The operation of the electromagnetic proportional valve controls the horsepower of the hydraulic pump to be reduced, so that the operating speed of the working machine is reduced.

B. Also, during the above-mentioned lifting operation, when the highest part of the tip of the work equipment reaches the boundary between the semi-hazardous area and the hazardous area, a command signal is sent from the controller to the solenoid valve of the pilot circuit for the remote control valve. Output. The operation of the solenoid valve shuts off the pilot circuit for the remote control valve, so that the work machine is stopped.

(2) A. When the highest end of the work equipment is being lowered, deceleration speed return processing and normal speed return processing are performed at the lower boundary surface of the dangerous area and the lower boundary surface of the semi-dangerous area, respectively. will be held. Thereby,
When the work equipment is in operation, the work equipment will not cause any chattering or shock at area boundary surfaces.

<3) A. By operating the setting switch in accordance with the height of the obstacle above, the current highest position among the parts of the working machine (referred to as the y1 position) can be stored in the controller as a danger area. (Here, the position stored in the controller is Y2.) Mouth. Movement of the work equipment is detected by a refraction motion detection means,
The detection signal is input to the controller. The controller calculates based on the above detection signal, and uses the height value of the highest position among the tip positions of the work equipment as a control information signal.
Output from the controller to the display. The display performs display based on the control information signal.

C. When the highest point among the tip positions of the work machine reaches the danger zone and the work machine is in the stop processing state, when the stop processing release switch is operated, the signal is input to the controller.

Based on the signal, the controller issues a control cut command signal to the relay contact leading to the solenoid for the electromagnetic valve. As the solenoid valve is released, the pilot circuit for the remote control valve becomes open, so that the work machine stop processing is canceled.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings. FIG. 2 is a side view of the hydraulic excavator 1 (an example is a hydraulic excavator equipped with a working machine for digging ditches).

In the figure, 2 is the lower traveling body of the hydraulic excavator 1, 3 is the upper rotating body, 4 is the working machine attached to the front part of the upper rotating body 3, 5 is the ditch digging boom of the working machine 4, and 6 is the ditch digging boom 5 , 7 is the front boom, 8 is the upper boom, 9 is the arm, 10 is the packet, 11 is the boom cylinder, 12 is the arm cylinder, 13 is the packet cylinder, l4 is the pin joint at the root of the rear boom 6, 15 is the float Bin connection part at the base end of boom 7, l6 is arm 9
The pin joint part at the base end, 16A is the front boom tip position which is the highest part near the pin joint part 16, 5o is the bottle joint part at the tip of arm 9, 50A is the highest part near the pin joint part 5o The arm tip position, l7 is the boom potentiometer attached to the pin coupling part l4, 18 is the offset potentiometer attached to the bottle coupling part 15, 15A is the rear boom tip position which is the highest part near the bottle coupling part 15, 19 is the arm potentiometer attached to the bottle joint 16, α is the boom inclination angle, β is the arm rotation angle, L1 is the aboom length, L2 is the front boom length, L3 is the upper frame length, and L4 is the arm length. It is. FIG. 3 is a plan view of the hydraulic excavator 1 in FIG. 2. In the figure, 20 is an offset cylinder;
γ is the offset angle, and , is the offset dimension. Fourth
The figure is a side view showing a danger area set in the hydraulic excavator 1. In the figure, range A is the dangerous area, range B is the semi-dangerous area, range C is the safe area, a is the area boundary between the safe area C and the semi-dangerous area B, and b is the area between the semi-dangerous area B and the dangerous area A. Boundary surface, C is the lower boundary surface of the semi-dangerous area set at a position slightly below the area boundary surface A (below by dimension M), and 2 is a position slightly below the area boundary surface entrance (below by dimension L). The lower boundary of the danger zone is set to
The dimension α is the distance from the zone boundary surface I to the zone boundary surface mouth, and the dimension b is the distance from the semi-dangerous zone lower boundary surface C to the zone boundary surface B. FIG. 1 is a circuit diagram showing a working height limiting device 22 according to the present invention. In the figure, 23L, 23
F1 is the left and right travel motor, 24 is the boom cylinder lIM
25 is a pilot switching valve for controlling the packet cylinder 13, 26 is a pilot switching valve for controlling the arm cylinder 12, 27 is a pilot switching valve for controlling the offset cylinder 20, 28 is an engine, and 29.30 is a pilot switching valve for controlling the engine 28. 31 and 32 are regulators of the first and second bombs 129 and 30, respectively, which are variable displacement hydraulic pumps to be driven; 37 is an electromagnetic proportional valve 38 is a solenoid of the electromagnetic proportional valve 37; 39 is a pilot pump, 40 is an oil tank, 41.42 is a remote control valve that operates the pilot switching valves 24, 27, 43
41 is a solenoid valve provided in the pilot circuit of the remote control valve 42, 44 is a solenoid of the solenoid valve 43, 45 is a controller, 46 is a memory, 47 is a stop processing release switch, 48 is a relay contact, 49 is a buzzer, 33 is a setting switch for working height limit, 34 is a reference setting switch for display, 3
5 is a display device. Note that by applying pilot pressure to the ports Pt and P″f of the regulators 31 and 32, the horsepower reduction control of the first and second bombs 29 and 30 can be performed.
Data such as lengths L1 to L5 of each part of the working machine 4 and rotation angles α, β, and γ of each part are stored in . FIG. 5 is a flowchart showing the functions of the controller 45.

Next, the functions of the working height control device 22 according to the present invention will be described with reference to FIGS. 1 to 5. A dangerous area A is set above the hydraulic excavator 1 in the vertical direction, a semi-dangerous area B is set below the dangerous area A, and a safety area C is set below the semi-dangerous area B. And each tip position 15A of the working machine 4. When the highest part of 16A and 50A reaches the area boundary surface A between the safety area C and the semi-dangerous area B during the lifting operation, the operating speed of the work equipment 4 is decelerated, and the operating speed of the work equipment 4 is reduced. The operation of the work equipment 4 is stopped when the boundary between the area B and the dangerous area A is reached.

Then, place the lower boundary surface 2 of the dangerous area at a position slightly (by the dimension L) below the area boundary surface 2 between the dangerous area A and the semi-dangerous area B, and the area boundary surface 2 between the semi-dangerous area B and the safe area C. The semi-dangerous area lower boundary surface C was set at a position slightly (by the dimension M) below A.

And each tip position 15A, 16A, 50A of the working machine 4
When the part at the highest position of the lowering operation reaches the area boundary face entrance between dangerous area A and semi-dangerous area B, it continues to pass through that operating state, and the lower part of the dangerous area When it reaches boundary surface 2, it returns to the deceleration speed of the deceleration processing state, and when it reaches the area boundary surface A between semi-dangerous area B and safe area C, it continues to pass through the deceleration processing state and returns to the above-mentioned semi-dangerous state. When reaching the lower boundary surface C, the normal operating speed is restored. Also, each tip position 15A of the working machine 4.
The device is equipped with a display means for displaying the highest position among 16A and 50A, a setting means for setting a danger area A, and a stop processing canceling means for canceling the stop processing when the work machine 4 is in the stop processing state.

Next, the functions of the working height limiting device 22 according to the present invention will be described. The movement of the work implement 4 is detected by potentiometers 17, 18, and 19 for the boom and offset arms, which are bending motion detecting means, and their detection signals are input to the controller 45, respectively. Based on the above detection signal, the controller 45 determines that when the highest position of each of the tip positions 15A, 16A, and 50A of the work equipment 4 reaches the area boundary surface A between the safety area C and the semi-dangerous area B. , the regulator 31 from the controller 45
．． A command signal is output to the electromagnetic proportional valve 37 of 32. ! Since the magnetic proportional valve 37 operates, the pilot pressure from the pilot pump 39 is applied to the oil passages 51, 52, the throttle 53, and the oil passage 54.
, through the electromagnetic proportional valve 37, oil passages 56, 57 and 58,
Boats Pf and P' of regulators 31 and 32, respectively
It acts on f. As a result, the first. 2nd bomb 29,3
0 is subjected to horsepower reduction control, so the operating speed of the working machine 4 is decelerated. In addition, when the highest position among the tip positions 15A, 16A, and 50a of the work implement 4 reaches the area boundary surface B between the semi-dangerous area B and the dangerous area A during the above-mentioned lifting operation, the controller 45 sends the solenoid valve A command signal is output to 43. Since the electromagnetic valve 43 is switched from the open oil passage position A to the shutoff oil passage position B, the pilot circuits for the remote control valves 41 and 42 are in a shut off state. Since the remote control valves 41 and 42 become inoperable, the work machine 4 is stopped.

Next, when the highest position of the tip positions 15A, 16A, and 50A of the work equipment 4 is being lowered, at the lower boundary surface 2 of the dangerous area and the lower boundary surface C of the semi-dangerous area, Deceleration speed return processing and normal speed return processing are respectively performed. In other words, in response to the deceleration process when the work equipment 4 is raised, the deceleration speed return process and the normal speed return process operate in a hysteretic manner, so the work equipment 4 moves smoothly without chattering or shock. You can do this. In addition, for obstacles such as electric wires above the hydraulic excavator 1, the height of the obstacle is confirmed, and the setting switch 33 is operated to decide to limit the working height of the working machine 4. That is, by operating the setting switch 33 in accordance with the height of the obstacle above, each tip position 15A. 16
^、Choose the current highest position of 50A to controller 4
5 can be stored as dangerous t4A. When the hydraulic excavator 1 is operated, the movement of the work implement 4 is detected by the bending motion detection means, and the detection signal is input to the controller 45. Based on the above detection signal, the controller 45 calculates the position of each tip of the working machine 4.
, 16A, and 50A is output from the controller 45 to the display 35 as a control information signal. The display 35 performs display based on the control information signal. Here, the display value displayed on the display 35 includes the reference setting switch 3 in addition to the absolute distance display.
The point in time when the switch 4 is turned on can be defined as O, and it can also be expressed as a relative distance to the position (Y+) of the highest part of the working machine 4. By visually checking the displayed value, the driver can confirm the distance from the highest part of the working machine 4 to the danger zone A above.

Further, when the work machine 4 is in the stop processing state, the switch 47 is operated. An operation signal from the switch 47 is input to the controller 45. Since the output signal from the controller 45 acts on the relay contact 48, the solenoid 44 of the solenoid valve 43 is de-energized. The solenoid valve 43 returns to the open oil path position A, and the remote control valves 41 and 42 can be operated. Also, the highest part of the work equipment 4 is in the semi-dangerous area B. When entering the danger area A, four buzzers each issue a warning such as an intermittent beep or a continuous beep in response to an output signal from the controller 45.

Note that the working height limiting device 22 is provided with boom, offset, and arm potentiometers 17, 18, and 19, and in addition, a packet potentiometer (
(not shown) at the arm tip 50, the position of the toe of the packet 10 can be detected, which is more effective.

Furthermore, as a method of using a detector other than a potentiometer, this work height limiting device can also be implemented by installing a stroke sensor to detect the extension/contraction length of each hydraulic cylinder and using the detection means at the tip of the work equipment. be.

Next, FIG. 6 is a circuit diagram showing another embodiment of the working height limiting device 22' according to the present invention. This working height limiting device 22' is different from the working height limiting device 22 described above in that when decelerating the working machine 4, a command signal from a controller 45'' is output to a control motor 60 such as a stepping motor. The control motor 60 operates and rotates the governor lever 62 of the engine 28 via the coupling mechanism 61.As a result, the rotation of the engine 28 is reduced to a low speed, so that the work in which the work equipment 4 is decelerated is performed. The functioning of the height limiting device 22' is similar to that of the working height limiting device 22.

Effects of the Invention In the working height limiting device according to the present invention, a semi-dangerous area and a dangerous area are set above the construction machine, and the work equipment is decelerated in the semi-dangerous area and stopped in the dangerous area. I made it. In addition, when the work equipment approaches an obstacle such as an overhead electric wire (in the case of raising the work equipment) and when moving away from it (in the case of lowering the work equipment), it exhibits a bisteresis-like transition. Furthermore, a stop processing canceling means for canceling the stop processing of the working machine is provided. As a result, when the highest part of the work equipment approaches an obstacle above, the operating speed is reduced to a low speed in the semi-dangerous area, and the work equipment can be stopped in the dangerous area without shock without causing load spillage. can. When the work machine moves away from the obstacle, it can be operated without chattering.

Therefore, in a construction machine equipped with the working height limiting device according to the present invention, the working height of the working machine is limited with a smooth feeling without shock or chattering, and accidental contact with obstacles above can be prevented.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing the working height limiting device according to the present invention, Fig. 2 is a side view of the hydraulic excavator, Fig. 3 is a plan view of the hydraulic excavator in Fig. 2, and Fig. 4 is a setting for the hydraulic excavator. FIG. 5 is a flowchart showing the functions of the controller, and FIG. 6 is a circuit diagram showing another embodiment of the working height limiting device according to the present invention. 4 ------------One working machine 15A, 16A. 50. - Rear boom, 11111 front boom, arm tip position 1 7, 1 8.
1 9-11---- Potentiometer 2 2.
2 2 ' -------
---------1 Display 3 7----------1 Solenoid proportional valve 4 3-Solenoid valve 45 45' Controller 4 7--------------------- ---Switch for canceling pause processing or above

Claims (3)

[Claims] (1) In a construction machine in which a working machine with a boom, an arm, a work tool, etc. connected in series is attached to the front part of the upper revolving body, and is equipped with an operation position detection means for detecting the position of the tip of the operating machine. , a dangerous area is set above the construction machine in the vertical direction, a semi-dangerous area is set below the dangerous area, and a safety area is set below the semi-dangerous area. When the highest part of the position reaches the boundary between the safe area and the semi-dangerous area during a lifting operation, the operating speed of the work equipment is decelerated, and the area between the semi-dangerous area and the dangerous area is A working height limiting device characterized in that it is configured to stop the operation of a working machine when it reaches a boundary surface. (2) In the working height limiting device according to claim 1, the lower boundary surface of the dangerous zone is located at a position slightly below the boundary surface between the dangerous zone and the semi-dangerous zone, and the lower boundary surface between the dangerous zone and the semi-dangerous zone is The lower boundary surface of the semi-dangerous area is set at a position slightly below the area boundary surface with the area, and when the highest position of each tip of the work equipment is lowered, the above position is equivalent to the dangerous area. When it reaches the boundary surface with the dangerous area, it continues to pass through that operating state, and when it reaches the lower boundary surface of the dangerous area, it returns to the deceleration speed of the deceleration processing state, and the semi-dangerous area and the safe area The work height is characterized in that the working height is configured such that when the workpiece reaches the boundary surface between the areas, the workpiece continues to pass through the deceleration processing state, and returns to the normal operating speed when the workpiece reaches the lower boundary surface of the semi-dangerous area. Limit device. (3) A display means for displaying the highest position of each tip of the work equipment, a setting means for setting a danger zone, and a stop processing canceling means for canceling the stop processing when the work machine is in a stop processing state. A working height limiting device according to claim 1 or claim 2.