JP2548978Y2 - Safety equipment for construction machinery - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine such as a hydraulic shovel and, more particularly, to a safety device for a construction machine having a structure driven by a hydraulic motor.

[0002]

2. Description of the Related Art In a conventional swivel type construction machine, a relative distance between the construction machine and a worker is constantly detected by a transceiver mounted on the construction machine and a transceiver carried by the worker, so that the vehicle can be located in a dangerous area. A safety device has been devised to notify both an operator (operator) and a worker of a construction machine of the intrusion of the worker through an alarm and a warning lamp when the worker enters.

[0003] However, with these safety devices alone, an accident such as an operator being pinched by the working device, being hit by the vehicle main body, or being directly hit by the working device is not stopped. In order to prevent such accidents, safety devices have been devised that stop all the movements of the construction machine, that is, both the working device and the vehicle body, simultaneously with the alarm.

[0004]

However, when such a construction machine is used at a narrow work site, the worker frequently approaches the construction machine, and the operation of the construction machine is stopped every time. There is a disadvantage that the efficiency is reduced.

[0005] The present invention has been made in view of such a point, and an object of the present invention is to provide a safety device that can ensure the safety of workers without lowering work efficiency.

[0006]

In order to achieve the above-mentioned object, a structure moved by a hydraulic motor, a control valve for changing a driving oil pressure supplied to the hydraulic motor in accordance with an operating oil pressure, and the control valve The following safety device is provided in a construction machine provided with an operation means for adjusting an operation oil pressure with respect to the following.

That is, a plurality of sensors for detecting the presence or absence of an obstacle including a human in a plurality of divided monitoring areas around the construction machine and an upper limit of an operating oil pressure for the control valve by the operating means are input. An electromagnetic relief valve that decreases based on the control signal, and a control unit that selects a control signal corresponding to the detection signal from each of the sensors and outputs the control signal to the electromagnetic relief valve, and detects the presence of an obstacle. Sometimes, the upper limit of the movement speed of the structure is reduced according to the monitoring area where the obstacle exists.

[0008] In addition to the above structure, the moving direction of the structure is detected, and the control means detects the moving direction of the structure only when detecting an obstacle in a monitoring area existing in the moving direction of the structure. The exercise speed is configured to lower the upper limit.

The "structure" in the specification of the present application means, for example, that an upper revolving body (working device) that is turned by a hydraulic motor is provided on a lower traveling body (vehicle body) that is driven by a hydraulic motor. In the case of a hydraulic excavator, it refers to the upper swing body or the lower traveling body.

[0010]

According to the present invention, an electromagnetic relief valve is controlled based on detection signals from a plurality of sensors for detecting the presence or absence of an obstacle including a human (operator), and an operating hydraulic pressure corresponding to a control valve by operating means is controlled. The upper limit is reduced.

Thus, for example, when a sensor in charge of a monitoring area relatively close to the construction machine detects a human or the like, the upper limit of the operating oil pressure is set to zero, and the upper limit of the operating oil pressure is gradually increased as the distance increases (however, less than the maximum). By setting so that, if there is an obstacle in the most dangerous work area, the movement of the structure will stop regardless of the operation of the operation means, and the movement speed of the operation means will increase as the distance increases Even if such adjustment is made, the actual movement speed becomes low.

Therefore, the operator (driver) can recognize the existence of the obstacle by the fact that the actual speed is lower than the speed expected by the driver, and the approximate existence of the obstacle can be recognized by the decrease rate of the upper limit speed. The position can also be recognized.

Thus, when the obstacle is relatively distant, the work can be carefully continued at a low speed, and the work can be performed efficiently without sacrificing safety. In addition, when an obstacle exists in a position where driving should not be continued, the movement of the structure is stopped irrespective of the operator's intention, which is very safe.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 2 and 3 are diagrams schematically showing a hydraulic shovel to which the present invention is applied. FIG. 2 is a side view, and FIG. 3 is a plan view.

The hydraulic excavator has an upper revolving unit 2 mounted on a lower traveling unit 1 so as to be revolvable, and a boom 3, a stick 4 and a bucket 5 connected to the upper revolving unit 2 in a rotatable manner. I have.

The lower traveling body 1 travels by being driven by a hydraulic motor (not shown), the upper revolving body 2 is driven by a hydraulic motor (not shown) to revolve, and the boom 3, the stick 4, and the bucket 5 are driven by a hydraulic motor (not shown). Hydraulic cylinders 6, 7, 8 respectively
, And is rotated.

As shown in FIG. 3, the hydraulic excavator is provided with a plurality of sensors 9a, 9b, 9c, 9d for detecting the presence of an obstacle including a human. Each of these sensors 9a, 9b, 9c, 9d has directivity and a predetermined detection range. In this example, the area to be monitored around the excavator is divided into four areas (first area, first area,
(The second area, the third area, and the fourth area), and the sensor 9a monitors the first area, the sensor 9b monitors the second area, the sensor 9c monitors the third area, and the sensor 9d monitors the fourth area. Like that. Sensors 9a, 9b, 9
As c and 9d, those that detect the presence of an object using ultrasonic waves, radio waves, infrared rays, or the like can be used.

FIG. 1 is a diagram showing a drive circuit of a hydraulic motor to which the safety device according to the present invention is applied. In the figure,
Reference numeral 11 denotes a hydraulic motor for rotating the upper rotating body 2, and the hydraulic motor 11 is connected to a hydraulic port 13 for supplying drive oil and a drain port 14 via a control valve 12.

The control valve 12 can continuously control the forward / reverse rotation and rotation speed of the hydraulic motor 11 in accordance with the operating oil pressure (control valve pilot pressure). Hydraulic port 16 for supplying operating oil via operation means 15, oil drain port 17
It is connected to the. By manually operating the remote control lever, the pilot pressure on the control valve 12 can be freely adjusted and set, whereby the right turning, left turning and turning speed of the upper turning body 2 can be arbitrarily adjusted. Can be.

Numerals 18 and 19 denote electromagnetic relief valves. These electromagnetic relief valves 18 and 19 cause the internal pressure of the operation oil supply pipes 20 and 21 between the control valve 12 and the remote control means 15 to exceed a set pressure. , The operation oil in the pipelines 20 and 21 is discharged to the oil drain ports 22 and 23 and the pipelines 20 and 21 are discharged.
This is a safety valve to keep the internal pressure below the set pressure. These electromagnetic relief valves 18 and 19 can change the above-mentioned set pressure according to an input control signal.

Reference numeral 24 denotes control means (signal processing circuit) having an adder, a solenoid valve drive amplifier circuit, and the like.
Detection signals from sensors 9a, 9b, 9c, 9d for detecting humans and the like are input to 4, and control signals for the electromagnetic relief valves 18, 19 are selected and output based on these detection signals.

In this embodiment, the relationship between the detection signal input to the control means 24 and the control signal (control valve pilot pressure) output from the control means 24 is set as shown in FIG.

That is, any of the sensors 9a, 9b, 9c,
If a detection signal indicating that a human or the like is present is not input from 9d, the control valve pilot pressure is not detected as _Pmax (the pressure at which the hydraulic motor 11 reaches the maximum output or the safety of the hydraulic circuit is reduced). Is output to the electromagnetic relief valves 18 and 19.

When a detection signal indicating the presence of a person or the like is input from the sensors 9b and 9d for monitoring the second area or the fourth area, the control valve pilot pressure becomes Ps ₂ (P
_max and the intermediate pressure) and a kind of control signals to zero pressure output to the electromagnetic relief valve 18 and 19, sensor 9a for monitoring the first area or the third area, that the human or the like is present from 9c Is input to the electromagnetic relief valves 18 and 19 such that the control valve pilot pressure becomes Ps ₁ (an intermediate pressure between Ps ₂ and zero pressure or zero pressure). Output.

[0025] Thereby, when no detection is made, the operation at the maximum output can be performed, and when a person or the like is present in the second area or the fourth area relatively far from the work position at that time, the operation is performed at a medium speed or less. When a person or the like is present in the first area or the third area which is relatively close, it becomes impossible to operate or operate at a low speed or lower.

Therefore, even if the operator (driver) does not notice the display lamp or the like indicating the presence of a person or the like, the operator can recognize the presence of the person or the like by restricting the driving speed. Yes, safety is improved.

In addition, it is possible to recognize the outline of the location of a person or the like (whether it is far from or close to the work position at that time, etc.) based on the limiting rate of the driving speed, and to limit the location according to the degree of danger. Work can be performed carefully at a speed lower than the speed, and work efficiency can be improved without lowering safety.

Further, when a person or the like exists in an area where the continuation of the work immediately leads to a disaster, it can be safely stopped regardless of the operator's intention.
In the above embodiment, four sensors 9a, 9b, 9
The four areas (first to fourth areas) around the excavator are monitored by c and 9d, the speed limit of the first or third area is strictly set, and the speed limit of the second or fourth area is set loosely. However, the present invention is not limited to this, and furthermore, a plurality of sensors can be provided and the speed can be set to be finely limited according to the risk factor of each monitoring area.

Further, the control means 24 in the above embodiment is used.
Is configured to limit the speed when detecting the presence of a person or the like regardless of the turning direction of the upper revolving unit 2, but detect the turning direction of the upper revolving unit 2 and determine the area on the turning direction side (for example, (First and second areas in case of left turn in FIG. 3)
If the speed is limited only when a human or the like is present in the vehicle, more efficient work can be performed.

Further, in the above embodiment, the safety device according to the present invention is applied to the drive circuit of the hydraulic motor 11 for rotating the upper revolving unit 2, but is also applied to the drive circuit of the hydraulic motor for moving the lower traveling unit 1. Good to do.

The present invention is not limited to the excavator,
It goes without saying that the present invention is applicable to all construction machines having a structure driven by a hydraulic motor.

[0032]

According to the present invention, when the presence of a person or the like is detected around the construction machine, the movement of the structure is not stopped uniformly, but the movement speed is determined according to the danger rate of the position of the structure. Can be limited, the operator (driver) can be made aware of the presence of a human (operator) or the like by the speed limitation, and work can be continued carefully according to the location of the person. There is an effect that work efficiency can be improved without lowering safety.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a main configuration of an embodiment of the present invention.

FIG. 2 is a side view showing a configuration of the hydraulic excavator according to the embodiment of the present invention.

FIG. 3 is a plan view showing a configuration of the hydraulic excavator according to the embodiment of the present invention.

FIG. 4 is a diagram showing a relationship between a detection signal from a sensor and a control valve pilot pressure in the embodiment of the present invention.

[Description of Signs] 1 Lower traveling structure 2 Upper revolving structure 9a, 9b, 9c, 9d Sensor 11 Hydraulic motor 12 Control valve 15 Remote control means 18, 19 Electromagnetic relief valve 24 Control means

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-142138 (JP, A) JP-A-61-53922 (JP, A) JP-A-48-44951 (JP, A) 84354 (JP, U)

Claims (2)

(57) [Scope of request for utility model registration] 1. A structure driven by a hydraulic motor,
In a construction machine having a control valve for changing a drive oil pressure supplied to the hydraulic motor in accordance with an operation oil pressure and an operation means for adjusting an operation oil pressure for the control valve, a monitoring area divided into a plurality of parts around the construction machine A plurality of sensors for respectively detecting the presence or absence of an obstacle including a human being, an electromagnetic relief valve for reducing the upper limit of the operating oil pressure for the control valve by the operating means based on an input control signal, and from each of the sensors. Control means for selecting a control signal corresponding to the detection signal and outputting the control signal to the electromagnetic relief valve, wherein when detecting the presence of an obstacle, A safety device for a construction machine, wherein an upper limit of a movement speed of a structure is reduced. 2. The safety device for a construction machine according to claim 1, wherein a movement direction of the structure is detected, and the control unit detects an obstacle in a monitoring area existing in the movement direction of the structure. A safety device for a construction machine, wherein the upper limit of the movement speed of the structure is reduced.