JPH0434137A - Working area monitor device for working vehicle for construction - Google Patents

Abstract

PURPOSE:To ensure an improvement in efficiency of a working vehicle and a worker and the safety by providing a working vehicle with an ultrasonic transmitter and receiver for covering a dangerous section having a determined radius, and providing the worker with a transmitter and receiver unit having an alarm device sensitive to it. CONSTITUTION:A monitor device is formed of an ultrasonic transmitter and receiver unit 3 on a working vehicle 1 side and an ultrasonic transmitter and receiver unit 12 provided with a warning buzzer 11 and a control unit 9 on a worker 10 side. The transmitter and receiver 3 on the working vehicle 1 side is constituted as to be spread in bevel form of horn type transmitters and receivers 7a-7l, or the control unit 9 is constituted as to perform the alarm control by the oscillating operation and signal receipt of each receiver 7a-7l. When the worker 10 enters into an alarm detecting area, the communication is conducted between the transmitter and receiver 3 on the vehicle 1 side and the transmitter and receiver 12 on the worker 10 side to confirm the mutual existences. An improvement in working efficiency of the working vehicle 1 and the safety of the worker 10 thus can be ensured.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a work area monitoring device for a construction work vehicle, and in particular, uses ultrasonic waves to detect a worker or the like who has entered the work area and issues an alarm. The present invention relates to a work area monitoring device for a construction work vehicle.

(Prior Art) At construction sites, construction machines such as power shovels and workers often work in the same work area at the same time.

In such cases, the operator of the construction machine or the worker working near the construction machine often comes into contact with the operating construction machine, resulting in human disasters such as death or injury.

Conventionally, as a means to prevent such human accidents, ultrasonic transducers were attached to the front or rear of construction vehicles.
This ultrasonic transducer emits ultrasonic waves in a predetermined direction, and by receiving the ultrasonic waves reflected from the worker, etc., the transducer can issue an alarm or automatically operate the brakes. Construction vehicles were to be stopped.

(Problem to be Solved by the Invention) However, in the conventional detection method as described above, the presence of an object is detected by receiving ultrasonic waves reflected from an object within the alarm detection area using a transducer. , It is difficult to determine whether the detected object is a worker or a stationary object.

Therefore, there is an inconvenience that the construction vehicle automatically stops in response to objects other than the worker, resulting in a problem of lowering the operating rate of the construction vehicle.

In addition, since the ultrasonic transducer is only installed in one place at the front or rear of the work vehicle, even if a worker enters the work area other than the detection area of the ultrasonic transducer, the The problem was that it could not be detected.

The present invention has been made in view of the above-mentioned points, and is capable of simultaneously monitoring the entire alarm detection area of a construction work vehicle.
An object of the present invention is to provide a work area monitoring device for a construction vehicle that can reliably detect a worker or the like who has entered the detection area.

(Means for Solving the Problems) The present invention will be explained in conjunction with FIGS. 1 and 2 which are one embodiment. A plurality of horn-shaped ultrasonic transducers 7a to 7I2 having a predetermined opening angle are arranged in a ring shape diagonally downward so as to cover an alarm detection area of a predetermined radius around the construction work vehicle l on the member 4. , an oscillation means 9I that generates ultrasonic waves of a predetermined frequency by applying an oscillation signal to each of the horn-type ultrasonic transducers 7a to 7ε, and an intruding object 10 that intrudes into the first-report detection area of the construction vehicle I.
A horn type ultrasonic transducer 78
The ultrasonic device has an ultrasonic receiver 121 that receives ultrasonic waves from ~7β, and emits ultrasonic waves of a different frequency from the notification means 11 that operates when receiving ultrasonic waves and the horn-type ultrasonic transducers 7a to 7β. When the invading object ultrasonic transducer unit I2 having the transmitter 126 and each of the horn-type ultrasonic transducers 7a to 7I2 receive an ultrasonic signal from the ultrasonic transmitter 126 on the invading object side. III 111 means 9 for detecting and monitoring an intruding object 10 based on a signal.

(Function) When each of the horn-type ultrasonic transducers 7a to 7β performs an oscillating operation, the ultrasonic waves from the apertures of each of these ultrasonic transducers 7a to 7p are transmitted in all directions of 360 degrees with the work vehicle 1 as the center. It is possible to simultaneously monitor a single alarm detection area.

Thereby, no matter which direction the intruding object 1o enters the g-signal detection area, it can be reliably detected.

Since ultrasonic waves of different frequencies are used for communication between the work vehicle 1 and the intruding object 10, detection and recognition of both parties is ensured.6 (Embodiment) Hereinafter, one implementation of the present invention An example will be explained based on FIGS. 1 to 4.

Figure 1 (a) is an overall configuration diagram when the work furnace area monitoring system of the present invention is applied to a power shovel, and Figure 1 (b)
FIG. 2 is a side view of the ultrasonic wave transmitting/receiving unit.

In the figure, 1 is a crawler-type power shovel, 2 is a driver's cab of the power shovel 1, and 3 is an ultrasonic transceiver unit that monitors the working area of the excavator 1. This ultrasonic transceiver unit 3 is a magnet co-producing unit. It is installed on the roof 2a of the driver's cab 2 by means of a stand 4 having a stand 4a.

The ultrasonic transceiver unit 3 includes a bottom plate 5 and an umbrella-shaped cover 6 that are horizontally attached to the upper end of a stand 4, and there is an opening angle of 30° in the circumferential direction between the bottom plate 5 and the cover 6. Pyramidal horn-shaped ultrasonic transducers 78 to 7Q are arranged radially in a ring shape in the circumferential direction.

Further, the opening surfaces of each of the ultrasonic transducers 7a to 7C are oriented diagonally downward at a predetermined angle (for example, 13.5 degrees) with respect to the horizontal plane.

9 is a control unit installed in the operator's cab 2 of the power shovel 1. This control unit 9 causes each of the ultrasonic transducers 7a to 7e to perform oscillation operation, processes the signals received by each of the ultrasonic transducers 7a to 7J2, and issues an alarm and controls the stoppage of the power shovel l. The system is configured as shown in FIG.

Further, IO is an object to be detected that enters the alarm detection area of the power shovel l, such as a worker, and this worker 10 carries an ultrasonic wave transmitting/receiving unit 12 with a built-in alarm buzzer 11.

As a result, when the worker 10 enters the alarm detection area of the excavator L, ultrasonic waves are transmitted between the ultrasonic wave transmitting/receiving wave x = -y of the power shovel 1 and the ultrasonic wave transmitting/receiving unit 12 of the worker 10. They communicate with each other, allowing them to recognize each other's presence and issue warnings.

Figure 2 shows the power, ultrasonic transceiver unit 3 for excavators.
and a specific circuit block diagram of the ultrasonic wave transmitting/receiving unit 1-12 for workers.

In the figure, an ultrasonic transceiver unit 3 for a power excavator is shown.
The control unit 9 includes a zero oscillation circuit 91 that simultaneously drives the ultrasonic transducers 7a to 7ε at a predetermined frequency (for example, 28 KHz), and amplifies the oscillation output from this oscillation circuit 91 to drive the ultrasonic transducer 7a. ~7ε, a detection circuit 93 that detects the ultrasonic signal from the worker side received by the ultrasonic transducer 7a~7ε, and this detection circuit 9.
Consisting of a signal processing circuit 94 that processes the detection signal output from 3 to control an alarm 95 and a stop control section 96 of the excavator I, and a power supply circuit 98 that supplies power to each circuit via a switch 97. be done.

The ultrasonic transducer unit 12 for workers also includes an ultrasonic receiver 121 that receives ultrasonic waves emitted from the ultrasonic transducers 7a to 7β of the power excavator l, and the ultrasonic receiver 1.
a detection circuit 122 that detects the ultrasonic signal received at 21; and a signal processing circuit 123 that processes the detection signal output from the detection circuit 122 to control the sounding of the alarm buzzer 11 and control the oscillation of the ultrasonic wave. , this signal processing circuit 12
Based on the oscillation command from 3, a predetermined frequency (for example, 21K
Hz) signal for a predetermined period of time, an amplifier circuit 125 that amplifies the oscillation output from this oscillation circuit 124, an ultrasonic transmitter 126 that is driven by the output of this amplifier circuit 125, and these circuits. and a power source 127 such as a dry battery that supplies power to the .

The transmitting and receiving range of the excavator-side ultrasonic transmitting/receiving unit 3 and the worker-side ultrasonic transmitting/receiving unit 12 is within a radius of 1 around the excavator l as shown in FIG.
The distance is around 0m.

Next, the operation of this embodiment configured as described above will be explained with reference to FIGS. 3 and 4.

When the switch 97 is turned on when monitoring the detection area of the power shovel 1, power is supplied from the power supply circuit 98 to each circuit, and the ultrasonic wave transmitting/receiving unit 3 is set to an operating state. When the oscillation circuit 91 operates accordingly, its oscillation output is transmitted to each of the ultrasonic transducers 7a to 7 via the amplifier circuit 92.
I2, each ultrasonic transducer 7a to 7I2. is operated, and the predetermined frequency (28KHz) generated from this
The ultrasonic waves are radiated diagonally downward from each opening surface over the entire 360° area.

At this time, the horizontal directivity characteristics of each ultrasonic transducer 7a to 712 become as shown by the broken line I in FIG. 3, and the vertical directivity characteristics become as shown by the broken line II in FIG. 4. , monitoring within the circle 20 shown by the solid line in FIG. 3 is possible from any direction of 360 degrees.

In such a state, when a worker 1O or the like carrying the ultrasonic transducer unit 12 enters the alarm detection area indicated by the circle 20, the ultrasonic receiver 121 is activated by any of the excavator-side ultrasonic transducers 7a to 7I2. To receive the ultrasound, the ultrasound is converted into an electrical signal. Then, the detection circuit 122 that receives this converted signal is connected to the ultrasonic transducer 7.
Only the ultrasonic signal of the frequency oscillated from 8 to 7I2 is extracted and outputted to the signal processing circuit 123.

The signal processing circuit 123 outputs a drive signal to the alarm buzzer II based on the detection signal from the detection circuit 122, and by sounding the alarm buzzer 11, the worker lO himself/herself enters the dangerous work area of the power shovel l. I know that there has been an intrusion. As a result, the worker 10 becomes aware of the danger and evacuates outside the detection area.

On the other hand, when the worker 10 enters the alarm detection area of the excavator 1, the worker himself! Upon receiving the notification, the signal processing circuit 123 gives a start command to the oscillation circuit 124. As a result, when the oscillation circuit 124 is activated, its oscillation output is applied to the ultrasonic transmitter 126 via the amplifier circuit 125, and the ultrasonic transmitter! 26 for a predetermined period of time.

When the ultrasonic transmitter 126 is driven, the ultrasonic wave (frequency 21 KHz-J) emitted from the ultrasonic wave transmitter 126 is radiated toward the ultrasonic wave transmitting/receiving unit 3 of the power shovel l.

When the ultrasonic waves emitted from the ultrasonic transmitter 126 on the worker's side are received by any of the ultrasonic transducers 7a to 7i on the excavator side, this ultrasonic wave is converted into an electrical signal and sent to the detection circuit. 93. The detection circuit 93 that receives this converted signal extracts only the ultrasonic signal of the frequency oscillated from the ultrasonic transmitter 126 and outputs it 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 by driving the alarm device 95, the power shovel is notified that a worker or the like has entered the alarm detection area. Notify the operator. When the worker 10 is present in the turning and working area of the power shovel 1, the power shovel 1 in operation is automatically stopped.

In this case, the signal processing circuit 94 determines the arrival time of the ultrasonic waves from the ultrasonic transmitter 126 on the worker's side, and when the result is determined to be less than a predetermined value, it sends a signal to the stop control unit 96 and outputs the power. All you have to do is stop shovel 1.

In this embodiment, each of the horn-type ultrasonic transducers 7a to 7β of the ultrasonic transducer unit 3 installed on the roof 2a of the driver's cab 2 of the power excavator I is arranged in a ring shape with the horn-shaped ultrasonic transducers 7a to 7β facing diagonally downward. This makes it possible to monitor the entire alarm detection area in a 360° direction centered on the excavator 1, so that workers IO, etc. can monitor the power excavator 1 in any direction in 360 degrees. Even if someone enters the alarm detection area, this can be reliably detected, and the detection area can be monitored at the same time.

In addition, the power shovel l and the worker 10 are configured to use ultrasonic waves of different frequencies to recognize each other's presence and issue an alarm, making it possible to reliably prevent workers from inadvertently intruding. In addition to being able to detect and identify objects, it also solves the conventional problem of power shovels stopping due to stationary objects such as telephone poles and fences.

Furthermore, since the stand 4 that supports the ultrasonic transducers 7a to 7I2 can be attached to and removed from the roof 2a of the driver's cab 2 by means of a magnet assembly 4a, the same ultrasonic transducer unit 3 can be used on other work vehicles other than power excavators. It can also be used for
When it is inconvenient, the ultrasonic wave transmitting/receiving unit 3 can be easily stored and stored in a place where it will not be exposed to wind and rain.

In the above embodiment, a case has been described in which the work area of a power shovel is monitored, but it goes without saying that it can also be used for construction work vehicles such as bulldozers, roller trucks, and backhoes.

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

Further, in the present invention, the form of the buzzer sound on the worker side can be changed depending on the distance between the work vehicle and the worker in the monitoring area, and the ringing of the buzzer on the work vehicle side can be controlled.

In this case, for example, as shown in Japanese Patent Application Laid-Open No. 64-12285, from the time when the ultrasonic transducer on the working vehicle side starts transmitting ultrasonic waves, the ultrasonic transducing unit on the worker's side The signal processing circuit on the work vehicle side calculates the round trip time until the ultrasonic wave is received from the side, sends out a response ultrasonic wave, and is received by the ultrasonic transducer on the work vehicle side. Find the distance between the car and the worker. When it is determined that the worker is within the monitoring detection area that is outside the dangerous work area where the work vehicle is turning (for example, the distance from the turning center is 1
3 m to 10 m), the ultrasonic transmitting/receiving unit carried by the worker makes a buzzer sound with a long interval, for example.

In addition, 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), the buzzer of the work vehicle will sound to alert the operator. Sound the buzzer on the worker's side.

Furthermore, when it is determined that the worker is in a dangerous turning area of the work vehicle (for example, when the distance from the turning center is 6 m to 0.
m), the buzzers on the work vehicle and worker side will sound at short intervals for emergencies.

In this way, the operating rate of the work vehicle and the safety of the workers can be further improved.

(Effects of the Invention) As is clear from the above description, according to the present invention, the support member provided on the construction vehicle has a
Multiple horn-shaped ultrasonic transducers with a predetermined opening angle are arranged diagonally downward in a ring shape to cover the alarm detection area of a predetermined radius in the 0° direction, so the alarm detection area can be monitored simultaneously. At the same time, it is possible to reliably detect an intruding object no matter which direction it enters the detection area.

Furthermore, since the work vehicle and the intruding object use ultrasonic waves of different frequencies to recognize each other's presence, the intruding object can be reliably detected and identified.

[Brief explanation of drawings]

FIG. 1(a) is an overall configuration diagram showing an embodiment of the present invention,
FIG. 1(b) is a side view of the ultrasonic transceiver unit on the work vehicle side in this embodiment, and FIG. 2 is a circuit showing a specific example of the ultrasonic transceiver unit on the work vehicle side and the intruding object side in this embodiment. The block diagram, FIG. 3 is an explanatory diagram showing the relationship between a working vehicle and its alarm detection area, and FIG. 4 is an explanatory diagram showing the directivity of the ultrasonic transducer with respect to an intruding object of the working vehicle. In the figure, 1 is a power shovel (work vehicle), 2 is a driver's cab,
3 is an ultrasonic transceiver unit, 4 is a stand (supporting member)
, 78 to 7β are ultrasonic transducers, 9 is a control unit, 1
0 is a worker (invading object), 11 is a warning buzzer, 12 is an ultrasonic wave transmitting/receiving unit, 91 is an oscillation circuit, 94 is a signal processing circuit, 95 is an alarm, 96 is a stop control unit, 121 is an ultrasonic receiver. 123 is a signal processing circuit, 124 is an oscillation circuit,
126 is an ultrasonic transmitter 6 Patent applicant Fujita Kogyo Co., Ltd.
Tokyo Keiki Co., Ltd.

Claims (2)

[Claims] (1) A support member installed upright on a construction work vehicle, and a predetermined ring arranged on the support member diagonally downward so as to cover an alarm detection area of a predetermined radius around the construction work vehicle. a plurality of horn-shaped ultrasonic transducers having an opening angle; an oscillation means for generating ultrasonic waves of a predetermined frequency by applying an oscillation signal to each of the horn-shaped ultrasonic transducers; and an alarm for the construction vehicle. An intruding object that intrudes into a detection area carries an ultrasonic receiver that receives ultrasonic waves from the horn-type ultrasonic transducer, and a notification means that operates when ultrasonic waves are received; an ultrasonic wave transceiver unit for an intruding object having an ultrasonic wave transmitter that emits ultrasonic waves of a frequency different from a horn type ultrasonic wave transducer; A work area monitoring device for a construction work vehicle, comprising: a 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 monitoring device for a construction work vehicle according to claim 1, wherein the support member for supporting the horn-type ultrasonic transducer is removably installed on the top of the construction work vehicle. .