JP2613489B2 - Work area monitoring device for construction vehicles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a work area monitoring device for a construction work vehicle,
In particular, the present invention relates to a work area monitoring device for a construction work vehicle that detects an operator or the like entering a work area using an ultrasonic wave and issues an alarm.

(Conventional technology) In construction sites and the like, construction machines such as power shovels and workers often work in the same work area at the same time.

In such a case, the operator of the construction machine and the worker working near the construction machine often inadvertently come into contact with the operating construction machine and cause human injury such as death or injury.

Conventionally, as a means for preventing such a human disaster, an ultrasonic transducer is attached to the front or rear part of a construction work vehicle, and ultrasonic waves are emitted from the ultrasonic transducer in a predetermined direction to perform work. An ultrasonic wave reflected from a person or the like is received by a transducer so that an alarm is issued or a brake is automatically operated to stop the construction work vehicle.

(Problems to be Solved by the Invention) However, in the conventional detection method as described above, the ultrasonic wave reflected from the object in the alarm detection area is received by the transducer to detect the presence of the object. It is difficult to determine whether the detected object is an operator or a fixed object.

Therefore, there is a disadvantage that the construction work vehicle is automatically stopped in response to an object other than the worker,
There is a problem that the operation rate of the work vehicle is reduced.

In addition, since the ultrasonic transducer is provided only at one position in the front or rear part of the working vehicle, even if an operator or the like enters the work area other than the detection area of the ultrasonic transducer, this may not be possible. There is a problem that cannot be detected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and can simultaneously monitor all alarm detection areas of a construction work vehicle and can reliably detect a worker or the like that has entered the detection area. It is an object to provide an area monitoring device.

(Means for Solving the Problems) The present invention will be described with reference to FIGS. 1 and 2 which are one embodiment. The present invention relates to a support member 4 erected on a construction work vehicle 1 and a support member 4. A plurality of horn-type ultrasonic transducers 7a to 7l each having a predetermined opening angle and arranged in a ring shape obliquely downward so that the member 4 can cover an alarm detection area of a predetermined radius around the construction work vehicle 1. An oscillating means 91 for generating an ultrasonic wave of a predetermined frequency by applying an oscillating signal to each of the horn-type ultrasonic transducers 7a to 7l;
The intrusion object 10 that intrudes into the alarm detection area is carried by the horn-type ultrasonic transducers 7a to 7l, and has an ultrasonic receiver 121 for receiving ultrasonic waves. An operating ultrasonic wave transmitter that emits ultrasonic waves of different frequencies from the operating notification means 11 and the horn-type ultrasonic wave transmitters / receivers 7a to 7l
Ultrasonic wave transmitting / receiving unit 12 for an intruding object having 126, and each horn type ultrasonic wave transmitter / receiver 7a to 7l is based on a signal when receiving an ultrasonic signal from the ultrasonic wave transmitter 126 on the intruding object side. And control means 9 for detecting and monitoring the intruding object 10.

(Operation) When the horn-type ultrasonic transducers 7a to 7l oscillate,
Ultrasonic waves from the opening surfaces of these ultrasonic transducers 7a to 7l are radiated in all directions of 360 degrees around the work vehicle 1,
It is in a position to monitor the alarm detection area at the same time.

Thus, even if the intruding object 10 enters the alarm detection area from any direction, it can be reliably detected.

Since the ultrasonic waves having different frequencies are used for the communication between the work vehicle 1 and the intruding object 10, the detection and the recognition of both are ensured.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 (a) is an overall configuration diagram when the work area monitoring system of the present invention is applied to a power shovel, and FIG. 1 (b).
FIG. 4 is a side view of the ultrasonic wave transmitting / receiving unit.

In the figure, reference numeral 1 denotes a crawler-type power shovel, 2 denotes a cab of the power shovel 1, 3 denotes an ultrasonic wave transmitting / receiving unit for monitoring a work area of the power shovel 1, and the ultrasonic wave transmitting / receiving unit 3 is a leg with a magnet. It is installed on the roof 2a of the cab 2 by a stand 4 having 4a.

The ultrasonic wave transmitting / receiving unit 3 includes a bottom plate 5 and an umbrella-shaped cover 6 horizontally attached to an upper end portion of a stand 4, and has an opening angle of 30 ° in a circumferential direction between the bottom plate 5 and the cover 6. The horn-type ultrasonic transducers 7a to 7l of pyramids are radially arranged in a ring shape in the circumferential direction.

The opening surfaces of the ultrasonic transducers 7a to 7l are directed obliquely downward at a predetermined angle (for example, 13.5 °) with respect to the horizontal plane.

9 is a control unit installed in the cab 2 of the power shovel 1. The control unit 9 oscillates each of the ultrasonic transducers 7a to 7l and controls each of the ultrasonic transducers.
Signals received at 7a to 7l are processed to perform alarm and stop control of the power shovel 1, and are configured as shown in FIG.

Reference numeral 10 denotes a detection target object that enters the alarm detection area of the excavator 1, for example, a worker.
Reference numeral 10 carries an ultrasonic transmission / reception unit 12 having a built-in alarm buzzer 11.

Thus, when the worker 10 enters the alarm detection area of the excavator 1, the ultrasonic transmission / reception unit 3 of the power shovel 1 communicates with the ultrasonic transmission / reception unit 12 of the worker 10 by ultrasonic waves. Be aware of each other's presence and be alerted.

FIG. 2 shows an ultrasonic transmission / reception unit 3 for a power shovel.
FIG. 2 is a specific circuit block diagram of an ultrasonic transmission / reception unit 12 for an operator.

In the figure, the control unit 9 of the ultrasonic wave transmitting / receiving unit 3 for a power shovel simultaneously drives the ultrasonic wave transducers 7a to 7l at a predetermined frequency (for example, 28 KHz). Oscillation circuit 91
An amplification circuit 92 that amplifies the oscillation output from the oscillation circuit 91 and supplies the amplified output to the ultrasonic transducers 7a to 7l;
A detection circuit 93 for detecting an ultrasonic signal from the worker side received by 7a to 7l, a detection signal output from the detection circuit 93 to process the alarm device 95 and a stop control unit of the power shovel 1
It comprises a signal processing circuit 94 for controlling 96, and a power supply circuit 98 for supplying power to each circuit via a switch 97.

The worker ultrasonic transmission / reception unit 12 includes an ultrasonic receiver 121 for receiving ultrasonic waves emitted from the ultrasonic transmitters / receivers 7a to 7l of the power shovel 1, and an ultrasonic receiver 121 for receiving the ultrasonic waves. A detection circuit 122 for detecting the detected ultrasonic signal, and a detection signal output from the detection circuit 122 to process the alarm buzzer 11
A signal processing circuit 123 that controls sound and controls the oscillation of ultrasonic waves; an oscillation circuit 124 that oscillates a signal of a predetermined frequency (for example, 21 KHz) for a predetermined time based on an oscillation command from the signal processing circuit 123; An amplifier 125 amplifies the oscillation output from the oscillator 124, an ultrasonic transmitter 126 driven by the output of the amplifier 125, and a power supply 127 such as a dry battery for supplying power to these circuits.

The transmittable / receivable range of the power shovel-side ultrasonic transmission / reception unit 3 and the worker-side ultrasonic transmission / reception unit 12 is, as shown in FIG.
The distance is around m.

Next, the operation of the present embodiment configured as described above will be described in the third.
This will be described with reference to FIGS.

When the switch 97 is turned on when monitoring the detection area of the power shovel 1, power is supplied to each circuit from the power supply circuit 98, and the ultrasonic transmission / reception unit 3 is set to an operating state. When the oscillation circuit 91 operates accordingly, the oscillation output is applied to each of the ultrasonic transducers 7a to 7l via the amplifier circuit 92, so that each of the ultrasonic transducers 7a to 7l is operated, and a predetermined Ultrasonic waves of a frequency (28 KHz) are radiated obliquely downward from the respective aperture surfaces over the entire region of 360 °.

At this time, the directional characteristics in the horizontal direction of each of the ultrasonic transducers 7a to 7l are as shown by the broken line I in FIG. 3, and the directional characteristics in the vertical direction are as shown by the broken line II in FIG. , Third
Monitoring within the circle 20 indicated by the solid line in the figure becomes possible from any direction of 360 °.

In this state, when the worker 10 or the like carrying the ultrasonic transmission / reception unit 12 enters the alarm detection area indicated by the circle 20, the ultrasonic receiver 121 is switched to any of the power shovel-side ultrasonic transmitters / receivers 7a to 7l. In order to receive the ultrasonic waves, the ultrasonic waves are converted into electric signals. Then, the detection circuit 122 that has received the converted signal extracts only the ultrasonic signal of the frequency oscillated from the ultrasonic transducers 7a to 7l and outputs this to the signal processing circuit 123.

The signal processing circuit 123 outputs a drive signal to the alarm buzzer 11 based on the detection signal from the detection circuit 122,
By ringing 11, the worker 10 knows that he has entered the dangerous work area of the excavator 1. Thereby, the worker 10 knows the danger by himself and evacuates out of the detection area.

On the other hand, when the worker 10 enters the alarm detection area of the power shovel 1, the worker himself receives a warning and at the same time, the signal processing circuit 123 gives a start command to the oscillation circuit 124. Thereby, when the oscillation circuit 124 operates, the oscillation output is applied to the ultrasonic transmitter 126 via the amplifier circuit 125, and drives the ultrasonic transmitter 126 for a predetermined time. When the ultrasonic transmitter 126 is driven, an ultrasonic wave to be emitted (frequency 2)
1 KHz) is radiated toward the ultrasonic transmission / reception unit 3 of the power shovel 1.

When the ultrasonic wave radiated from the ultrasonic wave transmitter 126 on the worker side is received by any of the ultrasonic wave transmitters and receivers 7a to 7l on the power shovel side, the ultrasonic wave is converted into an electric signal and detected by a detection circuit. Output to 93. Detection circuit 93 receiving this converted signal
Extracts only the ultrasonic signal of the frequency oscillated from the ultrasonic transmitter 126 and outputs this to the signal processing circuit 94. The signal processing circuit 94 outputs a drive signal to the alarm device 95 based on the detection signal from the detection circuit 93, and drives the alarm device 95 to detect that an operator or the like has entered the alarm detection area. Notify the operator. And worker 10
When the power shovel 1 is present in the turning and working area of the power shovel 1, the operating power shovel 1 is automatically stopped.

In this case, the arrival time of the ultrasonic wave from the ultrasonic transmitter 126 on the worker side is determined by the signal processing circuit 94, and when the result is determined to be equal to or less than the predetermined value, a signal is transmitted to the stop control unit 96 to output the power. The excavator 1 may be stopped.

As described above, in the present embodiment, the horn type ultrasonic transducers 7a to 7l of the ultrasonic transducer unit 3 installed on the roof 2a of the operator cab 2 of the power shovel 1 are ring-shaped with the diagonally downward direction. The excavator 1 is arranged so that it is possible to monitor the entire alarm detection area in the 360 ° direction centered on the excavator 1. Even if the user enters the alarm detection area, the detection can be surely detected and the detection area can be monitored at the same time.

In addition, since the power shovel 1 and the worker 10 are configured to recognize each other's existence using ultrasonic waves having different frequencies from each other and to issue an alarm, the worker or the like who intrudes carelessly can be surely. In addition to being able to detect and identify, it is possible to solve the problem that the power shovel 1 is stopped by stationary objects such as telephone poles and walls as in the related art.

In addition, since the stand 4 supporting the ultrasonic transducers 7a to 7l can be attached to and detached from the roof 2a of the cab 2 by the legs 4a with magnets, the same ultrasonic transducer unit 3 can be mounted on a working vehicle other than the power shovel. When not in use, the ultrasonic transmission / reception unit 3 can be easily stored and stored in a place where it is not exposed to wind and rain.

In the above embodiment, the case where the work area of the power shovel is monitored has been described.
Of course, it can also be used for construction vehicles such as backhoes.

Further, in the above embodiment, the case where the presence of each other is recognized by the alarm buzzer has been described, but a rotating lamp or other means may be used.

Further, in the present invention, it is possible to change the carrying of the buzzer sound on the worker side in accordance with the distance between the worker and the worker in the monitoring area, and to control the sounding of the buzzer on the worker side.

In this case, as shown in JP-A-64-12285, for example, from the point in time when the ultrasonic transmitter / receiver on the working vehicle starts transmitting ultrasonic waves, the ultrasonic transmitting / receiving unit on the worker side moves the work vehicle. The ultrasonic wave from the side is received and the ultrasonic wave for response is transmitted, and the reciprocating time until this is received by the ultrasonic transducer on the work vehicle is calculated by the signal processing circuit on the work vehicle, and the work is performed. Find the distance between the car and the worker. Then, when it is determined that the worker is present in the monitoring detection area that is out of the dangerous work area where the work vehicle is turning (for example, the distance from the turning center is 13 m to 10 m)
), The ultrasonic transmission and reception unit carried by the worker,
For example, the buzzer sounds at a long interval.

When it is determined that the worker is in the turning area of the work vehicle (for example, when the distance from the turning center is 10 m to 6 m)
Sounds the buzzer of the work vehicle to alert the operator and the buzzer of the worker.

Further, when it is determined that the worker is in the dangerous turning area of the work vehicle (for example, the distance from the turning center is 6 m to 0 m).
), The work vehicle and the buzzer on the worker side are sounded by an emergency sound with a short interval.

By doing so, the operation rate of the work vehicle and the safety of the worker can be further improved.

(Effects of the Invention) As is apparent from the above description, according to the present invention, the support member provided on the construction work vehicle is attached to the construction work vehicle mainly.
A plurality of horn type ultrasonic transducers having a predetermined opening angle are arranged in a ring shape obliquely downward so as to cover an alarm detection area of a predetermined radius in the direction of 0 °, so that the alarm detection area can be monitored simultaneously. In addition, even if an intruding object enters the detection area from any direction, it can be reliably detected.

In addition, since the work vehicle and the intruding object recognize each other using ultrasonic waves having different frequencies, the intruding object can be reliably detected and identified.

[Brief description of the drawings]

FIG. 1A is an overall configuration diagram showing one embodiment of the present invention,
FIG. 1 (b) is a side view of a working vehicle-side ultrasonic wave transmitting / receiving unit in this embodiment, and FIG. 2 is a circuit showing a specific example of a working vehicle-side and intruding object-side ultrasonic wave transmitting / receiving unit in this embodiment. FIG. 3 is an explanatory diagram showing the relationship between the work vehicle and its alarm detection area, and FIG. 4 is an explanatory diagram showing the directivity of the ultrasonic transducer to an intruding object of the work vehicle. In the figures, 1 is a power shovel (work vehicle), 2 is a cab,
3 is an ultrasonic wave transmitting / receiving unit, 4 is a stand (support member), 7a to 7l are ultrasonic wave transmitter / receivers, 9 is a control unit, 10
Is an operator (intruding object), 11 is an alarm buzzer, 12 is an ultrasonic transmission / reception unit, 91 is an oscillation circuit, 94 is a signal processing circuit, 95 is an alarm, 96 is a stop control unit, and 121 is an ultrasonic receiver , 123 is a signal processing circuit, 124 is an oscillation circuit, and 126 is an ultrasonic wave transmitter.

Continued on the front page (72) Inventor Toshi Nagahama 4-6-115 Sendagaya, Shibuya-ku, Tokyo Inside Fujita Industries Co., Ltd. (72) Setsuro Kimura 2-16-46 Minami Kamata, Ota-ku, Tokyo Tokyo, Ltd. In the instrument (72) Inventor Isao Takiguchi 2-16-46 Minami Kamata, Ota-ku, Tokyo Tokyo Incorporated (72) Inventor Hideji Matsuzawa 2-16-46 Minami Kamata, Ota-ku, Tokyo Tokyo Incorporated Inside the instrument

Claims (2)

(57) [Claims] 1. A support member erected on a construction work vehicle, and the support member is arranged in a ring shape obliquely downward so as to cover an alarm detection area of a predetermined radius around the construction work vehicle. A plurality of horn-type ultrasonic transducers having a predetermined opening angle; an oscillating means for generating ultrasonic waves of a predetermined frequency by applying an oscillation signal to each of the horn-type ultrasonic transducers; An intrusion object that intrudes into the alarm detection area of the horn is carried by the horn-type ultrasonic transducer, and has an ultrasonic receiver for receiving an ultrasonic wave. And the horn-type ultrasonic transducer, an ultrasonic transmitting and receiving unit for an intruding object having an ultrasonic transmitter that emits ultrasonic waves having a different frequency from the horn-type ultrasonic transducer, Ultrasonic A work area monitoring device for a construction work vehicle, comprising: control means for detecting and monitoring an intruding object based on a signal when an ultrasonic signal is received from a transmitter. 2. The work area of a construction work vehicle according to claim 1, wherein a support member for supporting the horn type ultrasonic transducer is detachably mounted on a top of the construction work vehicle. Monitoring device.