JPH07168987A - Proximity warning system and communication device used in the system - Google Patents

Abstract

(57) [Summary] [Purpose] Automatically detects when a work machine and a worker approach within a predetermined range within a common field such as a construction site, and outputs an alarm to alert the work machine operator or worker. We propose a proximity warning system that can prevent contact accidents by encouraging people. [Composition] One of the worker and the working machine is provided with a transmitting means for wirelessly outputting a signal of a long wave or a medium wave frequency band at a predetermined output level, and the other working machine or the worker is guided by the transmitting means. A means for receiving the signal having a specific coupling relationship is provided, and an alarm is output if the intensity of the signal received by the receiving means exceeds a predetermined reference intensity. Further, both the worker and the work machine are provided with a communication means so that they can exchange attention and instructions as they approach each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects that a working machine and a worker working in a common field such as a construction site approach within a predetermined range, outputs an alarm and outputs an alarm to prevent accidents. Regarding alarm system.

[0002]

2. Description of the Related Art At a construction site such as civil engineering / construction, a worker may enter an area where a working machine such as an excavator is used for work, and the worker enters the working range of the working machine to cause an accident. There was a risk of causing. Countermeasures against such dangers have been considered, such as monitoring by using a monitor camera, etc., or attaching a transceiver to the operator of the work machine or the worker so that they can communicate with each other. However, there was no reliable means for preventing accidents because they depend on the attention of people. Especially at such sites, work machines, materials,
The reality is that there are many cases where it is difficult to visually monitor because there is embankment and the visibility is poor.

[0003]

SUMMARY OF THE INVENTION Therefore, the present invention is designed to automatically detect that a working machine and a worker approach within a predetermined range and output an alarm to alert the operator of the working machine or the worker. We propose a proximity warning system that can prevent accidents.

In order to realize the approach warning system, a means for detecting the approach of the objects, that is, the distance between the objects is required, and particularly, a means for accurately detecting the distance in the range of 2 to 20 m is required. . By the way, conventionally, as a distance detecting means, a method using ultrasonic waves or the like has been known, but there is one that can easily detect distance without being affected by an obstacle or having directionality within the above range. I couldn't find it. Therefore, it is an object of the present invention to provide an approach warning system that can accurately detect the approach of a detection target in a range of 2 to 20 m (practically a range of 5 to 10 m).

Further, after the approach is detected, the worker and the operator of the working machine can appropriately communicate with each other so as to prevent an accident, thereby providing an approach warning system capable of safely continuing the work. .

[0006]

SUMMARY OF THE INVENTION The present invention detects when a first working body and a second working body working in a common field such as a construction site approach within a predetermined range and outputs an alarm. In the approach warning system according to claim 1, the first work unit is provided with a transmitting unit that wirelessly outputs a signal in a frequency band of a long wave or a medium wave at a predetermined output level, and a wireless communication unit. In the work body, an alarm output means for generating an alarm sound, a means for receiving the signal having an inductive coupling relationship with the transmitting means, an alarm output means and a voice generating unit are shared, and By providing a communication means capable of wireless communication and a means for controlling to output an alarm from the alarm output means if the intensity of the signal received by the receiving means exceeds a predetermined reference intensity, The above problems were solved. .

The signal may be output from a loop antenna that is provided substantially horizontally on the first working body and has a size much smaller than the wavelength of the signal.

The first working body is a working machine such as a construction machine, and a master unit having the transmitting means is attached to an upper surface of the working machine, and the talking means is portable by an operator of the working machine. In addition, the second work body is a worker, and the alarm output means, the receiving means, the communication means and the control means are integrally incorporated into a child machine to configure the system so that the worker can carry it. Good.

Further, there is provided voice control means for lowering the output level of the alarm sound generated from the voice generating section or for stopping the alarm sound when the communication means of the second work body is busy.
It is desirable to provide it on the second working body.

In the call device used in the approach warning system, which is provided as a call means for the first and second working bodies, an earphone is provided as a voice generating unit, and a bone conduction microphone is provided in the earphone. It is desirable that it be built-in and capable of inputting and outputting voice.

In the above-mentioned communication device, the speaker output of the received voice and the microphone input of the voice to be transmitted can be alternately switched, and at the same time, in a no-call state where there is no input / output signal higher than a predetermined level, the predetermined level is exceeded. It is desirable to provide a transmission / reception switching means for switching so as to give the reception right or the transmission right to the side receiving the signal input.

[0012]

The signal wirelessly output from the transmitting means in the first working body is received by the receiving means in the second working body, which is inductively coupled to the transmitting means, and is mainly guided as the signal here. Waves will be exchanged. This signal has a long-wave or medium-wave frequency band (30 KHz to 3 MH
z), a sharp attenuation characteristic is exhibited at a short distance of about 20 m from a transmission point far shorter than the wavelength (100 m or more). Therefore, even if various obstacles are present on the way and the influence of signal reflection or the like is exerted, it does not become so large as to significantly change the attenuation characteristic, and the intensity of the signal is detected by the second work body. By confirming the degree of attenuation, the distance from the first moving body can be detected with a small error, and the approach can be reliably detected and an alarm can be output.

Further, since a signal in the frequency band of long wave or medium wave is used, even if there are obstacles such as working machines, materials and embankments, they are so small as to cause no problem with respect to their wavelength.
It can be reliably received by the second mobile unit. It should be noted that after the approach is detected by the second work body, the call means may communicate with each other to call attention to each other.

By outputting the signal from the loop antenna provided substantially horizontally, a magnetic field orthogonal to the loop is formed in the radial direction with the antenna as the center, and the magnetic field is detected irrespective of the approach in any direction. it can. Moreover, since the size of the loop antenna is much smaller than the wavelength of the signal, the output of the electromagnetic wave from the antenna is suppressed to a very small value, and there is no danger of causing interference to the surroundings by the electromagnetic wave.

The first working body is a working machine such as a construction machine, and the second working body is a working machine.
The worker is the worker, the transmitting means is attached to the upper surface of the work machine to enable the loop antenna to be held substantially horizontally, and the other communication means can be carried by the operator of the work machine or the worker. , The system can be applied to the work site without affecting each work.

When the call means is talking on the second work body, the alarm sound accompanying the approach can be reduced or stopped so that the call in the call means is not hindered.

Further, the communication device used in this system is provided with an earphone having a bone conduction microphone as a voice generating unit, and a worker or an operator of the working machine can talk by simply attaching the earphone to the ear. Conversations can be conducted without hindrance to work, and conversations are possible even at a noisy work site.

Moreover, in the above-mentioned communication device, it is assumed that the speaker output and the microphone input are alternately switched, and the reception right or the transmission right is given to the side having the signal input earlier.
Since switching operation between transmission and reception is not required, and speaker output and microphone input are not performed at the same time, howling may occur even if the speaker output level and microphone sensitivity are sufficiently raised in consideration of noise at the work site. There is no inconvenience.

Embodiments will be described below with reference to the drawings.

FIG. 1 is an explanatory view showing an example of use of the present invention.
The example which aimed at the accident prevention between the mobile excavator A which is a working machine, and the worker B who works at the same construction site is shown.
The excavator A has a transmission / reception unit 1 as a master unit fixed to the horizontal surface of the ceiling, and an alarm unit 2 in the operator room. The operator C of the work machine A carries the communication device 3. The worker B attaches the slave unit 4 for exchanging signals with the master unit to the waist with a belt or the like.

FIG. 2 is a block diagram for explaining the structure of the approach warning system used as shown in FIG.

The transmission / reception unit 1 has a long-wave or medium-wave frequency band (preferably 500 K) through the loop antenna 5.
An FM band (for example, 60M) is transmitted via a transmitter 6 that outputs a modulated signal L of Hz or less) and a known whip antenna 7.
A receiving unit 8 for receiving the second modulated signal E of (Hz), an input unit 10 including means 9 for setting an approach distance to be detected,
When a modulation signal L corresponding to the approach distance set by the input unit 10 is output from the transmission unit 6 with a microcomputer at a predetermined timing, and when the reception unit 8 receives the second modulation signal E, the modulation signal L is output. The alarm unit 2 is provided with a control unit 14 for controlling to output an alarm. The distance setting means 9 sets the approach distance to be detected to 5
It can be set within a range of 10 m, and the transmitter 6 outputs the modulated signal L having an output level according to the set distance.

Since the loop antenna 5 is arranged horizontally in the unit 1 and the unit 1 is fixed horizontally with respect to the excavator A, the loop antenna 5 is always kept substantially horizontal, and the current of a predetermined frequency is applied. By flowing the magnetic field, a magnetic field orthogonal to the loop is periodically formed in the radial direction with the antenna 5 as the center, and the modulated signal L (mainly an induced wave) can be output to the front, rear, left, and right of the excavator A. Further, the loop antenna 5 is formed by winding a conductor wire in a circular shape having a diameter of 20 to 30 cm for 1 to 3 turns. If the frequency used for this is 500 KHz, for example, the wavelength is 600 m. Since the size of the antenna is much smaller, almost no electromagnetic waves are output.

The modulation signal L is preferably 500 KHz or less, for the following reason. This type of system needs to be easily usable by anyone without requiring a license, and therefore must be used without being regulated by the Radio Law. Further, since the modulated signal L exhibits a sharp attenuation as described above, it is necessary to transmit at a high output to some extent in order to accurately detect the approach distance of 10 m or more. According to the Radio Law Enforcement Regulation, the electric field strength generated according to the frequency band is limited, and according to the method of measuring the electric field strength, the lower the frequency, the higher the allowable output level becomes. Then, the modulation signal is 500 KH
If it is less than or equal to z, 10 without being regulated by the Radio Law
It was obtained as a result of the test that a modulated signal capable of detecting an approach distance of m or more in a stable manner can be output.

The alarm unit 2 comprises an output section 13 for outputting an alarm by a speaker 11 and a lamp 12,
In response to an output command from the control unit 14, a voice output and a warning by blinking a lamp are output.

The communication device 3 transmits and receives an FM band communication signal F to enable communication with a worker B working in a common field, and as shown in FIG. 3 in consideration of ambient noise. Earphone 15 with built-in known bone conduction microphone
Calls are possible by (details will be described later).

The slave unit 4 receives the modulated signal L from the transmitting unit 6 via the induction antenna 16 composed of a ferrite core coil, and the well-known whip antenna 18 to perform a second high frequency modulation. A transmission unit 19 that transmits a signal E, a communication unit 20 that transmits and receives the communication signal F to enable communication with the communication device 3, and an output unit 21 that generates an alarm sound.
Similarly to the earphone 15, an earphone 22 that has a bone conduction microphone built therein and performs a call through the call section 20 and outputs an alarm sound from the output section, and detects the intensity of the modulation signal received by the receiving section 17. If the detected intensity is equal to or higher than a predetermined reference intensity, the control unit 24 controls the earphone 22 to output an alarm via the output unit 21 and the high frequency signal E from the transmission unit 19. .

The induction antenna 16 efficiently receives an induction signal from the loop antenna 5 installed horizontally,
It is necessary to install it almost vertically as shown in FIG.
For this reason, the antenna 16 is installed in the slave unit 4 so that the worker wearing the slave unit 4 stands upright in a standing posture, and the slave unit 4 is compared in the direction of the antenna 16 even when the worker sits down or squats down. It is supposed to be attached to the waist of the worker as a place that does not change dynamically.

The output section 21 outputs an alarm if the modulated signal L is equal to or higher than a predetermined reference intensity as described above, but during the alarm output, a call is made in the call section 20 and a signal input (call device) of a predetermined level or higher is performed. 3) or a voice input from the bone conduction microphone), a switching signal accompanying this is received from the call section 20 to reduce the output level of the alarm and perform a switching operation so as not to hinder the call. I have it. Instead of reducing the output level, it is also possible to operate to stop the alarm sound only during a call.

FIG. 3 shows the call unit 20 used in the above embodiment.
3 is an explanatory view showing the configuration of the earphone 22 and the earphone 22.
Also, the earphones 15 have almost the same configuration.

The earphone 15 comprises an earphone body 31, an earpiece 32 made of a soft material, a bone conduction type microphone 33, and a speaker 34. The voice signal E received by the call section 20 is output from the speaker 34, and the earphone is also used. Two
The voice spoken by the worker wearing the 2 is the microphone 3 by bone conduction.
Sound can be collected at 3 and transmitted from the call unit 20. The call unit 20 includes a receiving unit 35 that receives the call signal F via the antenna 18, a transmitting unit 36 that outputs the call signal F from the antenna 18, and a transmission / reception switching unit 37 that switches between reception and transmission. There is.

The transmission / reception switching unit 37 includes means for detecting the level of the signal received by the receiving unit 35 and the signal collected by the microphone 33. In a normal state in which a signal exceeding a predetermined level is not input, reception / transmission is performed. If no signal is connected to either side and a signal of a predetermined level or higher is detected, the signal side is connected. That is, if there is a signal input at a predetermined level or higher through the receiving section 35, the signal is connected to the receiving side and the received signal is output from the speaker 34. During this time, the calling side is disconnected and the worker speaks. Even if the signal F from the transmitter 36
Is never output. Further, in the normal state, if a signal of a predetermined level or more is input from the microphone 33, the voice connected to the transmitting side and collected by the microphone 33 is output as the signal F from the transmitting unit 36, and the signal received by the receiving unit 35 during this period. Is not output from the speaker 34 as voice.

When the transmission / reception switching unit 37 detects a signal input above the predetermined level, the switching signal described above is output to the output unit 21, and the output unit 21 switches the output level of the alarm sound based on this signal. It will be.

Next, the operation of the system configured as described above will be described with reference to FIGS. 4 and 5.

The loop antenna 5 provided on the work machine A is periodically (1) at a predetermined timing given by the control unit 14.
-5 times / second) for a fixed time (5-10 milliseconds) at a predetermined frequency (preferably 5) in the medium wave or long wave frequency band.
Current of less than 00 KHz) and a modulation signal L
Is output intermittently. The modulated signal L is output at the output levels P ₁ and P ₂ according to the approach distances X ₁ and X ₂ that can be set by the distance setting means 9.

The output modulated signal L has a size much smaller than the signal wavelength of the loop antenna 5,
There is almost no output of electromagnetic waves, and it is output mainly as a magnetic field signal (induced wave) generated by energizing the antenna. As shown in FIG. 5, these signals are rapidly attenuated substantially inversely proportional to the square or the cube of the distance from the antenna 5, and in an actual field where noise shielding is not performed, it depends on the output level, but the antenna 5
If it is away from 50 to 100 m, it becomes too weak to measure accurately.

In the transmitter / receiver 4 carried by the worker B, the modulated signal L (mainly an induced wave) is applied to the induction antenna 16 which is inductively coupled to the loop antenna 5 as shown in FIG.
Is received instead of the induced voltage. The receiving unit 17 processes the received signal by an amplifier, a bandpass filter or the like and sends it to the control unit 24, and the control unit 24 intensifies the signal Y ₁
· Y ₂ is compared with the reference intensity Ys to be compared with (field strength). In FIG. 5, the intensity curve Y ₁ shows the attenuation characteristic according to the distance of the signal output at the output level P ₁ ,
Similarly, the intensity curve Y ₂ shows the attenuation characteristic at the output level P ₂ .

When the reception intensities Y ₁ and Y ₂ are equal to or higher than the reference intensity Ys, the worker B approaches the approach distance X ₁
When it is determined that the approach is made within X _2, the earphone 22 outputs an alarm sound via the output unit 21 to alert the worker B to the attention. At the same time, the transmitter 19 outputs the second modulated signal E to notify the approach of the worker B to the work machine A side.

The alarm output from the output unit 21 is the reception intensity Y.
_It continues until ₁ · Y ₂ falls below the reference intensity Ys. In addition,
Call from the communication device 3 or the earphone 2 while the alarm is being output.
2 has a voice input (signal input of a predetermined level or higher) in a built-in microphone, and when this is detected by the call unit 20, the output unit 21 lowers the output of the alarm sound and the transceiver unit 2
Allows 0 to call operator C. If the call is interrupted for a certain period of time and the reception intensities Y ₁ and Y ₂ are still at or above the reference intensity Ys, the alarm sound is output again at the normal level.

When the receiving section 8 of the working machine A receives the second modulated signal E from the transmitting section 19, the control section 14 outputs an alarm sound from the speaker 11 via the output section 13 and blinks the lamp 12. The operator C is notified that the operator B is approaching. Here, the operator C and the worker B can exchange attention and instructions with each other by using the communication device 3 and the communication unit 20.

The present invention is not limited to the above embodiments, and various embodiments are conceivable without departing from the scope of the claims. For example, the first work body may be the worker and the second work body may be the work machine. In this case, the worker carries the master unit integrally incorporating the transmitting means and the call means, and at least the alarm output means and The operator of the working machine may carry the child machine integrally incorporating the communication means. Further, even when the first and second work bodies are both working machines, the invention can be applied without any trouble.

[0041]

As described above, the first work body is the second work body.
Since an approach to the work body within a predetermined range is automatically detected and an alarm is output, a contact accident or the like can be prevented. In particular, the approach can be accurately detected within a range of about 2 to 20 m without being affected by an obstacle or having directionality, which is extremely effective in preventing a contact accident between a working machine and a worker at a construction site. Further, since the first and second work bodies are provided with the communication means, the work can be safely carried out by exchanging cautions and instructions with each other as they approach each other.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a usage example of the present invention.

FIG. 2 is a block diagram illustrating a configuration of an example system.

FIG. 3 is a configuration explanatory diagram of a call unit and earphones used in the embodiment.

FIG. 4 is an explanatory diagram of a main part of the embodiment system.

FIG. 5 is a characteristic diagram of reception intensity in the example system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmitter / receiver unit as a master unit 2 Alarm unit 3 Communication device 4 Slave unit 5 Loop antenna 6 Transmitter section of first working body 17 Receiving section of second working body 20 Calling section of second working body 21 Second work Body alarm output unit 24 Second work unit control unit A First work unit working unit B Second work unit worker E Second modulated signal F Call signal L Modulated signal

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoichi Takeda 1825, Amamiya, Sarahaku-shi, Nagano MK Seiko Co., Ltd. ) Inventor Terumasa Nakajima 1825 Amamiya, Aramiya, Sarahaku-shi, Nagano MK Seiko Co., Ltd.

Claims (6)

[Claims] 1. An approach alarm system for detecting when a first work body and a second work body working in a common field such as a construction site approach within a predetermined range and outputting an alarm. Transmitting means for wirelessly outputting a long-wave or medium-wave frequency band signal at a predetermined output level to the first work body;
A wireless communication means is provided, and the second work body is
An alarm output means for generating an alarm sound, a means for receiving the signal having an inductive coupling relationship with the transmitting means, and an alarm output means and a voice generating section are shared, and a wireless call with the call means is possible. An approach warning system comprising: a calling means and a means for controlling to output an alarm from the alarm output means if the strength of a signal received by the receiving means exceeds a predetermined reference strength. 2. The approach warning system according to claim 1, wherein the signal is output from a loop antenna provided substantially horizontally on the first work body and having a size much smaller than the wavelength of the signal. Alarm system. 3. The approach alert system according to claim 2, wherein the first work body is a work machine such as a construction machine, and a master unit provided with the transmitting means is attached to an upper surface of the work machine to perform the call. The means can be carried by the operator of the work machine, and the second work body is a worker, and the alarm output means, the receiving means, the communication means and the control means are integrally incorporated into a slave machine, and the worker is A proximity warning system that is portable. 4. The approach warning system according to claim 1, wherein the output level of the warning sound generated from the sound generating unit is reduced or the warning sound is stopped when the communication means of the second work body is talking. A cordless handset used in an approach warning system, wherein the voice control means is provided on the second work body. 5. The call device used in the approach warning system according to claim 1, wherein the call device is provided as a call means of the first and second work bodies, the earphone is provided as a voice generating unit, and the earphone is provided in the earphone. Is a communication device used in the proximity warning system, which is characterized by a built-in bone-conduction microphone that enables voice input and output. 6. The communication device used in the approach alert system according to claim 4, wherein the speaker output of the received voice and the microphone input of the voice to be transmitted are alternately switched to each other, and the input / output of a predetermined level or more is performed. A speech communication apparatus for use in an approach warning system, comprising transmission / reception switching means for switching so as to give a reception right or a transmission right to a side where a signal having a predetermined level or more is input in a no-call state without a signal.