JPH05331882A - Safety device of construction machine - Google Patents

Abstract

PURPOSE:To increase the safety by providing a controller which carries out the operation of the values of a speed signal and a position signal, and outputs a stop signal to prevent the operating part from contacting with an obstacle and a stopping means to stop the operating part by a stop signal. CONSTITUTION:When a back hoe moves to the rear side at a crawling speed, the speed signal is set to be a position signal to start the operation of a controller 10 when an obstacle 22 invades in a rear side perceiving area 16 which forms the minimum separation distance L1 in the processing area of perceiving sensors 5 and 6 at the rear side of the back hoe. When the back hoe moves to the rear side at a medium speed, the position signal is set to make the area in which the separation distance is larger than the L1. When it moves rearward at a high speed, the position signal is set to make the area of the maximum separation distance. Furthermore, the controller 10 expands or contracts the separation distance in each area according to the value of the speed signal, and it operates a stopping means 15 when an obstacle 28 approaches the inside of the area, so as to stop the back hoe.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects the separation distance between each operating part of a construction machine and an obstacle by a sensing sensor, and when the presence of the obstacle is detected within a predetermined value within the sensing area, the operation is performed. The present invention relates to a safety device for automatically stopping the operation of the machine, detecting the speed of the operating part of the machine, and causing the stopping means to operate within a safe range where the predetermined value in the sensing area is minimum accordingly. ..

[0002]

2. Description of the Related Art When an obstacle enters the working range of a vehicle-type construction machine or within the exclusion zone, the driver himself / herself recognizes it and stops the driving operation. A means for stopping has been proposed in the past, and as a method therefor, the presence of the obstacle is detected, and a probe signal transmitter such as an ultrasonic wave attached to the machine and a reflected wave from the obstacle are detected. It can be detected by a reflected wave detector that can be used, or an obstacle itself, for example, a transmitter is attached to a moving body such as a worker, and an obstacle signal from the transmitter is received by the machine. When the machine detects the obstacles and the obstacles are in a dangerous range, the engine of the machine is automatically stopped, or the operation of the operation levers for operating each part is disabled.

For example, FIG. 8 is an example disclosed in Japanese Examined Patent Publication No. 2-28026, which belongs to the latter, but shows a case where the mobile obstacle in the figure is the worker 21.
Reference numeral 2 is a transmitter attached to the head of the vehicle, and reference numeral 23 is a bulldozer, which is a typical example of a vehicle construction machine that works by moving the machine body back and forth, and receivers 24, 24. ,. ． ． Is installed. FIG. 9 is a block diagram showing the engine stopping means, showing a state in which the fuel cut solenoid 25 is energized.
Reference numeral 5 is connected to the positive electrode of the power supply 29 via the starting switch 26 and the normally closed contact 28a of the relay 27. Receiver 24
Is connected to the controller 30 and the controller 3
The output side of 0 is connected to the relay coil 28b of the relay 27.

When the starting switch 26 is turned on in the above-described structure, the current of the power source 29 is supplied to the solenoid 25 through the starting switch 26 and the normally closed contact 28a of the relay 27. When the solenoid 25 is energized, the fuel governor is freed and the fuel flows from the fuel injection pump to the engine via a fuel control linkage (not shown). When the worker 21 shown in FIG. 8 is in the vicinity of the bulldozer 23 in such a state, the receiver 24 receives the signal transmitted by the transmitter 22 carried by the worker 21, and the signal of the receiver 24 is transmitted to the controller 30. Is input to and amplified by
The relay coil 28b of the relay 27 is energized, as a result, the normally closed contact 28a is turned off, no current flows through the solenoid 25, no fuel flows from the fuel injection pump, and the engine stops.

On the other hand, in a machine, such as a power shovel, in which the upper revolving structure is mainly revolved to operate each part during work, when a person or an obstacle enters the revolving range, this is detected. A technique for stopping the turning is disclosed in Japanese Patent Publication No. 1-271534. This technique is shown in FIG. 1 which shows a turning range when the upper-part turning body turns.
At 0, the circle 36 having the turning radius R when the boom 34 and the arm 35 are operated so that the bucket 33 is farthest from the turning center O is the turning radius. Reference numerals 31 and 32 are ultrasonic sensors attached to the side of the upper swing body.
If 7 is a person or other obstacle that has entered the circle 36, the ultrasonic wave transmitted from the ultrasonic sensor 31 is reflected at 37, and the receiving portion of the sensor receives this, and the hydraulic circuit shown in FIG. Activate.

This operation will be described with reference to FIG. 11. The pressure oil from the hydraulic pump driven by the engine is switched by the swing valve 38, and the swing motor 39 turns right or left. Swing motor 39
An electromagnetic switching valve 40 is provided in the middle of the pipeline leading to
When a signal based on the reflected ultrasonic wave from the ultrasonic sensor 31 or 32 acts on the receiving portion thereof, the electromagnetic switching valve is actuated, and the pipe path leading to the swing motor 39 is cut off, so that the upper swing body is blocked by the obstacle 37. Stops approaching or colliding with automatically.

In any of the above-mentioned two prior arts, when various sensors detect an obstacle within the maximum danger range where danger may occur in the traveling direction of the machine, the left-right direction, or the operable range of the work tool, there is nothing. The conditions are to stop the occurrence of an accident by stopping the engine of the machine, stopping the turning motion, and operating a safety device that issues an alarm.

[0008]

As described above, in the prior art, if the sensing areas of a plurality of sensors are set in advance and an obstacle is present in any one of the sensing areas of the respective sensors, it is safe. Since the device is made to operate, safety can be expected during work, but it works regardless of work conditions, resulting in a decrease in work efficiency.
For example, the sensing distance in the traveling direction of the bulldozer must be set in advance so that the sensor can detect the presence of obstacles and stop the aircraft safely even when the machine is running at maximum speed. In addition, when turning a work tool such as a bucket like a power shovel, the presence of an obstacle in the turning range when the bucket is set to the maximum position from the turning center is detected, and at that time, Even if the upper revolving superstructure is at the maximum revolving speed, a safe stop must be made. An object of the present invention is to provide a safety device that minimizes the contradiction between the safety device and the work efficiency as described above.

[0009]

In order to solve the above problems, the present invention has taken the following means. That is, a) by moving the machine body forward and backward, or by rotating the upper swing body, the work device is moved to near the outer periphery of the machine body of the construction machine for performing work, for example, an ultrasonic sensor. It is composed of multiple sensing sensors, etc. that emit a probe signal like this, detect a reflection signal from an obstacle in a predetermined sensing area, detect a separation distance indicating a position related to it, and output it as a position signal. (2) A speed detecting means including a position detecting means, and (b) a speed sensor that directly or indirectly detects the traveling speed of the machine, the turning speed of the revolving structure, and outputs the magnitude as a speed signal or a speed command amount signal. Or a speed command amount detecting means, and c) built-in when a position signal from the above-mentioned sensing sensor and a speed signal or an operating speed command amount signal from a speed response sensor are input. A controller having a function of outputting a stop signal when the distance between the moving body and the obstacle due to the position signal increases as the signal value from the speed sensor increases, and d) from the controller Stop signal having the function of stopping the operation of the machine, turning of the upper swing body, braking action, or issuing an alarm by the stop signal.

[0010]

[Function] Position signals output by the sensing sensor and the speed sensor,
When the speed signal or the operation speed command amount signal is input to the controller and becomes a position signal indicating that the separation distance between the moving part of the machine body and the obstacle is less than a predetermined value, the controller outputs a stop signal. However, at this time, the arithmetic function of the controller operates, and the larger the speed signal is, the larger the position signal is, that is, the larger the separation distance is, the more the stop signal is output from the controller to the stop means. In this way, the machine is moved, the upper revolving superstructure is stopped, or they are braked.However, as described above, the position signal value from the sensor detects when the stop signal is output from the controller. The distance from a certain obstacle depends on the speed signal from the speed sensor or the operation speed command amount signal. Therefore, when the moving speed of the machine and the operating speed of the upper revolving superstructure are high, the distance to the obstacle is relatively large, and when the operating speed is low, the separation distance is small. Since it is the time point, the stop means will not operate at a separation distance more than necessary.

An embodiment of the present invention will be described below with reference to the drawings. 1 to 7 are views showing an embodiment in which the safety device according to the present invention is applied to an all-hydraulic backhoe as a typical example of construction machinery, and FIGS. 1 to 3 show that the backhoe moves rearward. 4 to 6 are plan views for explaining the operating conditions of the safety device of the present invention when turning the upper swing body of the backhoe to the right front, respectively. FIG. 7 is a block diagram showing the configuration of the safety device according to the present invention and the respective functions. In these figures, 1 is a boom, an arm,
The front attachment, which consists of an actuator that rotates the bucket and the hydraulic power source of the main body, etc., has a structure in which the lower traveling body supports the entire machine and controls the traveling. It has an actuator (not shown) for traveling driven by a source. An upper revolving structure 3 is rotatably mounted on the lower traveling structure 2 through a revolving bearing, and its revolving operation is driven by an oil pressure source of the main body (not shown).
The structure is made by.

A driver's cab 4 is provided on the upper revolving structure 3, and a driver operates an operating device arranged near the driver's seat in the driver's cab 4 to freely run, turn, and front-attach the machine 1. Performing the desired work by operating in the same manner as a general backhoe, in the present invention,
For example, in the cab 4 on the upper swing body 3, a controller 10, a speed sensor 11, and a stopping means 15 whose functions will be described later are provided.
In addition, in the vicinity of the outer periphery of the aircraft, for example, ultrasonic waves are directed generally outward, and the reflected wave from an obstacle in that direction is received to output the presence or absence of the obstacle and its separation distance as a position signal. Is a position detecting means including an ultrasonic sensor that can detect the obstacles 5 and 6 that detect an obstacle behind the machine or the front attachment 1 and the upper swing body 3 that detects an obstacle in the turning direction. , 8,
9 and the like are provided.

Next, the above-mentioned sensing sensors 5, 6, 7, 8,
9, controller 10, speed sensor 11, stopping means 15
The configuration, function, etc. of will be described with reference to the block diagram of FIG. Among the above, the speed sensor 11 detects the traveling speed or turning speed of the backhoe, and if necessary, the magnitude of the operating speed of the components of the front attachment 1 as the magnitude of the electric signal, and sends the speed to the controller 10 for each operating location. The signal is input, and the detection method is
For example, there is a speed detecting means for indirectly obtaining a speed signal by detecting the operation amount of each actuator operated by the driver, or a method for detecting the inflow / outflow amount of pressure oil to / from each actuator. The speed command amount detecting means may be indirectly used, such as a method of detecting the speed response of the rotating shaft driven by the method or a method of detecting a change in the ground angle of the rotating member. Can be achieved by using

The controller 10 has a calculation unit and a signal output unit, and an obstacle in the sensing area obtained by the detection sensors 5, 6, 7, 8 and 9 and a moving unit on a predetermined body are provided to the calculation unit. When the position signal indicating the separation distance of the above and the speed signal of the moving portion or the operation speed command amount signal obtained by the speed sensor 11 are input, the faster the speed indicated by the signal is, The output timing from the signal output unit is calculated so that the separation distance indicated by the position signal value is set large.
For example, when the backhoe moves backward at a slow speed, as shown in FIG. 1, when the obstacle 22 enters the rear sensing area 16 forming the minimum separation distance L1 within the sensing areas of the sensing sensors 5 and 6, the signal output unit is activated. The speed response signal is set so that it becomes the position signal value that starts, and the rear sensing area 1 where the separation distance is L2 which is larger than L1 when moving backward at medium speed.
Similarly, when moving backward at a high speed, the position signal is set so that the maximum separation distance L3 and the rear sensing area 18 are obtained. As another example, when the upper revolving structure 3 of the backhoe is turned to the right along with the front attachment, as shown in FIG. 4, at a very low turning speed, the turning sensing area 1 having the smallest separation angle response θ1 with respect to the turning direction.
When the obstacle 22 approaches 9 and the signal output unit of the controller 10 is activated for the first time, the calculation unit performs calculation so as to set the position signal value by inputting the speed signal. In high-speed turning, the divergence angle is θ1 and θ2, and the turning sensing area is 2 as shown in Figs.
At 0 and 21, the obstacle 22 is detected.

In this way, the rear sensing areas 19, 2 are
The separation distance and the separation angle in the range of 0, 21 and the like are enlarged or reduced according to the value of the speed signal in the calculation unit of the controller.
When the obstacle 22 approaches the range, the controller 1
The output unit of 0 receives this and outputs a stop signal to the stop means 15, so that the operation of the front attachment 1 and the machine body is stopped without coming too close to the obstacle 22. It should be noted that the faster the operating speed of the front attachment 1 and the machine body is, the more the stopping means 15 operates, even if the stopping means 15 operates. In addition, the position of the controller 10 with respect to the obstacle 22 to which the stop signal should be output according to the speed signal or the operation speed command amount signal from the speed sensor 11 is set as the position signal value, so that the distance and angle are safe and effective. Stop the operation of the machine.

Further, in one example of the stopping means 15, when a stop signal from the controller 10 is input to the electric oil converter 12, as shown in FIG. 7, the electric signal is converted into a hydraulic signal here. , A hydraulic switching valve for operating an actuator for traveling, turning, etc., regardless of the position of the operating lever, a hydraulic switching valve neutral return means 13 for disabling the switching is operated, or a braking means 14 is provided as necessary. It is also possible to activate the built-in alarm device 23. The stop means 15 having such a function can be easily realized by a combination of conventional techniques. For example, the electro-hydraulic converter 12 normally closes a port that communicates with a hydraulic power source, but a stop signal. Is a solenoid valve that opens when it acts on the receiving portion, and when this pressure oil acts on the oil chamber of the hydraulic pressure switching valve neutral return means 13, a switching that shuts off the pilot pressure operation of the pilot pressure switching type hydraulic pressure switching valve for actuators. A valve may be used, and as the braking means 14, there is a method in which when the pressure oil acts on the brake cylinder, a braking force is applied to the output rotary shaft of the traveling / turning actuator and one brake disc. As still another example, instead of the electro-hydraulic converter 12 and the hydraulic switching valve neutral return means 13, traveling,
An electromagnetic switching valve that directly shuts off the internal oil passage by a stop signal may be used in the main circuit of the turning actuator.

According to the present invention having the above-described configuration and function, the operating speed of traveling, turning, etc. is detected by the speed sensor 11, and the speed signal or the operating speed command amount signal is input to the arithmetic unit of the controller 10, The faster the operating speed is, the larger the position signals of the obstacles in the sensing areas of the plurality of sensing sensors, which are input simultaneously, are large, and the slower the operating signals are, the smaller the position signals are output from the output unit of the controller 10. The stop signal is changed so as to activate the stop means. Therefore, when the operating speed is slow, the distance or angle between the obstacle and the obstacle at the time of starting the operation of the safety device of the present invention can be set smaller than that of the conventional one, and in the precise work in a narrow place. Can also be used effectively as a safety device, and during strong and quick work, the distance or angle between the obstacle and the obstacle at the start of operation of the stopping means is large, and it is sufficient to slow down and stop the high operating speed. Secure a safe distance or angle.

In the embodiments shown in FIGS. 1 to 6, the safety backhoe is used only for the direction in which the body of the hydraulic backhoe moves backward and the direction in which the front attachment moves when the upper swing body turns right. Although the arrangement example of the sensing sensor has been described, the present invention is not limited to this, and in addition to this, the setting positions and directions of a plurality of sensing sensors, and the calculation unit of the controller 10 based on the speed signal from the speed detector 11 are used for setting. By changing the power position signal value variously and outputting a stop signal from the output section, the existence of obstacles when the machine is moving forward and turning to the left is known, and stop is automatically started from the most rational point. Needless to say, it can be used as a safety device against a start of braking, a warning, and the like, and further, a front attachment and an abnormal approach between a specific part of the body and an obstacle.

[0019]

According to the present invention, the faster the operating speed of the construction machine is, the longer the distance / angle between the obstacle and the specific part of the machine or machine is, and the slower the operating speed is. When the distance / angle between the obstacle and a specific part of the machine or machine becomes smaller, the stopping means of the safety device is activated, so when performing strong and quick construction in a relatively large area with a construction machine. When an obstacle tries to approach its operating range, the stopping means will start operating at the distance and angle necessary for decelerating and stopping from its fast operating speed, but on the other hand, in a narrow space or in a precise construction. When it is necessary, the stopping means automatically starts after the distance and angle are small enough to decelerate and stop the machine body having a slow operating speed. Therefore, regardless of the operating speed, when an obstacle enters a preset range, the stopping means is activated, and in some cases, the safety is sufficiently ensured as compared with the prior art in which the stopping means sometimes stops with an extra margin. Work efficiency can be improved when engaging in work types.

[Brief description of drawings]

FIG. 1 is a plan view illustrating an operation of a safety device of the present invention when a hydraulic backhoe is moving at a slow reverse speed.

FIG. 2 is a plan view for explaining the operation of the safety device of the present invention when the hydraulic backhoe is moving backward at medium speed.

FIG. 3 is a plan view illustrating the operation of the safety device of the present invention when the hydraulic backhoe is moving backward at high speed.

FIG. 4 is a plan view for explaining the operation of the safety device of the present invention when the upper swing body of the hydraulic backhoe is turned right at a slow speed.

FIG. 5 is a plan view illustrating the operation of the safety device of the present invention when the upper swing body of the hydraulic backhoe is turned right at medium speed.

FIG. 6 is a plan view for explaining the operation of the safety device of the present invention when the upper swing body of the hydraulic backhoe is swung right at high speed.

FIG. 7 is a block diagram showing the configuration and function of the present invention.

FIG. 8 is a side view showing a state in which a conventional safety device mounted on a bulldozer detects an obstacle.

9 is a block diagram showing functions of the safety device of FIG. 8. FIG.

FIG. 10 is a plan view showing a state in which a conventional safety device mounted on a power shovel detects an obstacle within a turning range.

11 is a hydraulic circuit diagram adopted in the safety device of FIG.

[Explanation of symbols]

 5, 6, 7, 8, 9 Sensing sensor 10 Controller 11 Speed sensor 15 Stopping means 16, 17, 18 Rear sensing area 19, 20, 21 Turning direction sensing area 22 Obstacles L1, L2, L3 Separation distances θ1, θ2, θ3 separation angle

Claims (2)

[Claims] 1. A position detecting means for detecting a relational position between a construction machine and an obstacle around the construction machine, a speed detecting means for detecting an operation speed of an operating portion as a signal, and a speed signal from the speed detecting means. Also, a controller that calculates the value of the position signal from the position detecting means, outputs a stop signal safely so that the operating portion does not come into contact with an obstacle, and an extra separation distance does not occur; A safety device for a construction machine, which is provided with a stop means for stopping an operating part by a stop signal output. 2. A position detecting means for detecting a relational position between a construction machine and an obstacle around the construction machine, a speed command amount detecting means for detecting an operation speed command amount signal of an operating portion as a signal, and the speed command. A stop signal is calculated so that the operating speed command amount from the amount detecting means and the value of the position signal from the position detecting means are calculated, and the operating portion does not come into contact with an obstacle safely and an extra separation distance does not occur. A safety device for a construction machine, comprising: a controller that outputs a signal, and a stop unit that stops an operating portion by a stop signal output by the controller.