JPH1088628A - Radio type annunciator for construction equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transmit a working sign etc., surely to an operator in a driver's cab for a construction equipment even at the time of large noises in a jobsite. SOLUTION: A transmitting device 3 consisting of a control switch and a transmitter transmitting communication radio waves by closing the control switch is installed to a hydraulic backhoe 1, and a receiving device 14 composed of a receiver receiving the communication radio waves transmitted from the transmitting device 3 and a speaker informing the reception of the communication radio waves by the reciver is mounted on a dump car 12 conducting Joint works with the hydraulic backhoe 1. Accordingly, a working sign, etc., can be transmitted from the driver of the hydraulic backhoe 1 to the driver of the dump car 12 through the communication radio waves.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless alarm device for a construction machine suitable for use in a construction machine such as a hydraulic shovel, a hydraulic crane, a wheel loader, a dump truck, and the like. The present invention relates to a wireless notification device for construction machines that transmits and receives communication radio waves between them and transmits work cues and the like.

[0002]

2. Description of the Related Art At mines, civil engineering sites, construction sites, and the like, a plurality of workers cooperate while operating and operating a plurality of construction machines such as hydraulic excavators and dump trucks. For this reason, for example, when starting work, when finishing loading earth and sand and materials from the hydraulic excavator to the dump truck, the workers give work signals to each other and confirm the progress of the work.

In this case, a horn is generally provided in a hydraulic excavator, a dump truck, or the like, and an operator presses a horn in a cab to generate an audible alarm. Work signals are sent to the other party.

However, in mines, civil engineering work sites, construction work sites, etc., extremely loud noises are continuously generated, such as the sound of breaking earth and sand by hydraulic excavators and the like, and the sound of moving construction materials. . For this reason, even if a horn is generated from a horn such as a hydraulic excavator or a dump truck, the audible alarm is drowned out by the surrounding noise, and the operator cannot hear the audible alarm. .

In order to solve such a problem, a horn is provided at the tip of the arm of the hydraulic excavator so that the horn can be brought closer to a dump truck or the like as a work partner, and the horn can be emitted from the horn. (Japanese Patent Application Laid-Open No. 6-49868).

[0006]

By the way, according to the above-mentioned prior art, in a work site where the noise is very intense, such as in a mine, the beeping sound of the horn is drowned out by the surrounding noise, and the work signal and the like are given. There is a problem that communication cannot be reliably made to the other party.

[0007] Further, there are cases where the worker is working with the windows of the cab of the hydraulic shovel or dump truck closed to avoid heat. In such a case, there is a problem that the audible alarm does not reach the cab and the operator in the cab cannot hear the audible alarm.

The present invention has been made in view of the above-mentioned problems of the prior art, and is capable of reliably transmitting a work signal and the like to a worker in a cab of a construction machine even when the work site is loud. An object is to provide a wireless alarm device for a machine.

[0009]

Means for Solving the Problems To solve the above-mentioned problems, the invention according to claim 1 is provided with a transmitting means provided on a first construction machine for transmitting a communication radio wave and a transmitting means provided on a second construction machine. Receiving means for receiving the communication radio wave transmitted from the transmission means, the transmission means comprising: an operation switch provided in a cab of the first construction machine; and a communication radio wave by closing the operation switch. And a receiver for transmitting the communication radio wave transmitted from the transmission means, and the receiver provided in the cab of the second construction machine, the receiver transmits the communication radio wave. And a notifying means for notifying that it has been received.

According to the above configuration, when a worker working in the cab of the first construction machine sends a work signal to a worker working in the cab of the second construction machine. The operator working in the cab of the first construction machine closes the operation switch provided in the cab. Thereby, the transmitter provided in the first construction machine transmits the communication radio wave to the outside.

[0011] Then, the receiver provided in the second construction machine receives the communication radio wave transmitted from the transmitter of the first construction machine. As a result, the notifying means provided in the cab of the second construction machine is activated, and notifies a worker who is working in the cab of the second construction machine of a work signal or an alarm.

According to a second aspect of the present invention, the transmission means includes a transmission distance changing means for changing a transmission distance of a communication radio wave.

According to the above configuration, the transmission distance of the communication radio wave transmitted from the transmitter provided in the first construction machine can be changed by the transmission distance changing means. This allows
For example, if the transmission distance of the communication radio wave is limited to a predetermined range by the transmission distance changing means, the communication radio wave can be transmitted only from the first construction machine to the second construction machine within the predetermined distance range. it can.

According to a third aspect of the present invention, the receiving means includes a receiving sensitivity changing means for changing the receiving sensitivity of the communication radio wave.

According to the above configuration, the receiving sensitivity of the receiver provided in the second construction machine can be changed by the receiving sensitivity changing means. Thus, for example, if the reception sensitivity is set to a predetermined sensitivity by the reception sensitivity changing unit, only the communication radio waves transmitted from the first construction machine within a predetermined distance range with respect to the second construction machine are received. be able to.

According to a fourth aspect of the present invention, the operation switch is
The configuration is such that the alarm switch provided in the operator's cab of the first construction machine is also used.

With the above configuration, at the same time as the worker working in the cab of the first construction machine presses the alarm switch, the operation switch is closed, and a communication radio wave is transmitted from the transmitter.

According to a fifth aspect of the present invention, the notifying means includes a second
A speaker is provided in the operator's cab of the construction machine, and when the receiver receives a communication radio wave, a warning sound is generated from the speaker.

With the above configuration, when the receiver provided in the second construction machine receives the communication radio wave transmitted from the transmission means of the first construction machine, the speaker sounds in the cab of the second construction machine. A warning sound is emitted in the driver's cab.

[0020]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

Here, FIGS. 1 to 4 show an example in which the wireless alarm device for construction equipment according to the first embodiment of the present invention is applied to a hydraulic shovel and a dump truck.

Reference numeral 1 denotes a hydraulic shovel as a first construction machine, and a cab 2 of the hydraulic shovel 1 is provided with a transmitting device 3 as transmitting means for transmitting communication radio waves.

The transmission device 3 includes an operation switch 4 provided in the operator cab 2 of the hydraulic shovel 1 and a transmitter 5 for transmitting a communication radio wave by closing the operation switch 4.
It is composed of

Further, regarding the operation switch 4, FIG.
3, reference numeral 6 in FIG. 3 denotes a driver's seat provided in the driver's cab 2, and a box-shaped control box 7 is disposed on the left side of the driver's seat 6. Is provided with a control lever 8. Further, the upper end of the control lever 8 is a grip portion 8A. Reference numeral 9 denotes an alarm switch disposed at the upper end of the grip portion 8A of the control lever 8, and when the alarm switch 9 is pressed,
A horn provided on the excavator 1 operates to emit an audible alarm toward the periphery of the excavator 1.

The alarm switch 9 also serves as the operation switch 4. That is, when the alarm switch 9 is depressed, the alarm switch operates, and at the same time, the operation switch 4 is closed, and a communication radio wave is transmitted from the transmitter 5.

Reference numeral 10 denotes an operation pedal provided on the floor of the cab 2, and reference numeral 11 denotes a travel lever extending upward from the floor of the cab 2.

The transmitter 5 of the transmission device 3 includes an oscillation circuit, an amplification circuit, and the like.
In a control box 7 provided in the driver's cab 2 of the vehicle. Further, the transmitter 5 is provided with a transmitting antenna 5A, and the transmitting antenna 5A is provided, for example, in the cab 2. When the alarm switch 9 is pressed by the operator in the cab 2, the operation switch 4 is pressed.
Is closed, a communication radio wave is transmitted from the transmitting antenna 5A of the transmitter 5.

Here, the transmission output of the transmitter 5 is, as shown in FIG.
Is set in advance to be within a circle having a radius d1 with the position Q as the center. For example, when excavating works such as earth and sand, rocks and the like are performed jointly, it is usually sufficient to be able to transmit communication radio waves within a radius of about 100 m around the position Q of the excavator 1. For this reason, the transmission output of the transmitter 5 is set in advance so that the radius d1 is approximately 100 m.

A predetermined transmission frequency is set in the transmitter 5 in advance. As a result, a communication radio wave of a predetermined frequency is output from the transmitter 5. The transmitter 5 may be provided with a transmission frequency varying means so that the frequency of the communication radio wave can be changed.

On the other hand, reference numeral 12 denotes a dump truck as a second construction machine. In a driver's cab 13 of the dump truck 12, a receiving device 14 as a receiving means for receiving the communication radio wave transmitted from the transmitting device 3 is provided. Is provided.

Here, the receiving device 14 is provided in the driver's cab 13 of the dump truck 12 and the receiver 15 for receiving the communication radio wave transmitted from the transmitting device 3 and confirms that the receiver 15 has received the communication radio wave. Speaker 16 as notification means for notifying
It is composed of

The receiver 15 comprises an amplifier circuit, a detection circuit, and the like, and is provided, for example, in a control section 18 of the cab 13 shown in FIG. The receiver 15 is provided with a receiving antenna 15A, and the receiving antenna 15A is provided, for example, in the cab 13. Then, the receiver 15 receives the communication radio wave transmitted from the transmitting device 3 by the receiving antenna 15A.

Here, the receiving sensitivity of the receiver 15 is set in advance so that the receiving distance range of the communication radio wave is within a predetermined range. For example, when excavation work such as earth and sand, rocks and the like is performed jointly, a radius of 10
It is usually sufficient if communication radio waves can be received within a circle of about 0 m. Therefore, the range of the communication radio wave reception distance is limited to the dump vehicle 12.
The reception sensitivity of the receiver 15 is set in advance such that the radius of the receiver 15 is about 100 m with the position of the center as an example.

Further, the same receiving frequency as the transmitting frequency set for the transmitter 5 is set in the receiver 15 in advance. As a result, only the communication radio waves transmitted from the transmitter 5 are received, and radio waves of other frequencies are not received. Note that the receiver 15 may be provided with a reception frequency varying means so that the reception frequency can be changed.

The speaker 16 will be described in detail with reference to FIG. 4. In FIG.
3 shows a driver's seat provided in front of the vehicle, and a control unit 18 provided with instruments for operating the dump truck 12 is provided in front of the driver's seat 17. The control unit 18 is provided with a handle 19 at a position facing the driver's seat 17. And the speaker 16
Is located near the handle 19 and the control unit 18
It is provided above.

The speaker 16 is connected to the output side of the receiver 15, and when the receiver 15 receives the communication radio wave transmitted from the transmitting device 3, emits a buzzer sound such as "buzz, boo".

The wireless alarm device for construction equipment according to the present embodiment has the above-described configuration. Next, the operation thereof will be described.

For example, when excavation work of earth and sand and rocks is started in a mine, or when the loading of earth and sand from the excavator 1 to the dump truck 12 is completed as shown in FIG. An operator (hereinafter, referred to as a “transmitting worker”) sitting in a driver's seat 6 provided in the driver's cab 2 of the dump truck 12 is provided with a driver's seat 17 provided in the driver's cab 13 of the dump truck 12. Workers sitting at
A work signal is sent to the "reception worker." Further, in order to prevent safety during work, a warning may be issued from the transmitting worker to the receiving worker.

At this time, the transmitting worker depresses the alarm switch 9 provided in the cab 2 of the excavator 1. As a result, the operation switch 4 of the transmission device 3 is closed, and the communication radio wave is transmitted from the transmitter 5.

When a communication radio wave is transmitted from the hydraulic excavator 1, the receiver 15 of the receiving device 14 of the dump vehicle 12 receives the communication radio wave. As a result, the speaker 16 provided in the driver's cab 13 of the dump truck 12 emits a warning sound. Therefore, the receiving worker working in the driver's cab 13 of the dump truck 12 can hear the audible alarm from the speaker 16 and confirm the work signal or warning from the transmitting worker.

Thus, according to the present embodiment, the transmitting device 3 is provided in the excavator 1 and the receiving device 14 is provided in the dump truck 12.
And transmitting a communication radio wave from the transmitting device 3 to the receiving device 14 so that a horn sounds from a speaker 16 provided in the cab 13 of the dump truck 12,
It is possible to reliably transmit a work signal or an alarm from the transmitting worker working in the cab 2 of the excavator 1 to the receiving worker working in the cab 13 of the dump truck 12. it can.

That is, when the transmitting worker depresses the alarm switch 9 of the excavator 1, the operator's cab 13 of the dump truck 12 is turned on.
Since the audible alarm is emitted from the speaker 16 provided inside, the receiving worker working in the cab 13 of the dump truck 12 can directly hear the audible alarm emitted from the speaker 16. Accordingly, when the noise around the work site is extremely strong, and even when the receiving worker closes the window of the driver's cab 13 and works, the receiving worker does not receive the work sent from the transmitting worker. Signals or warnings can be reliably heard, and work can be facilitated and work safety can be improved.

Further, since the operation switch 4 of the transmission device 3 is also used as the alarm switch 9 provided in the cab 2 of the excavator 1, the following effects are obtained.

The transmitting worker working in the cab 2 of the excavator 1 conventionally pushes down the audible switch 9 and issues a horn provided on the excavator when issuing a work signal or an alarm. Was ringing. For this reason, the operation of pressing down the alarm switch 9 when issuing a work signal or an alarm is a familiar operation for the transmitting worker. That is, since the operation switch 4 is also used as the alarm switch 9, the transmission-side worker can
By operating the transmission device 3 in the same operation as in the related art, a work signal or an alarm can be directly issued to the dump truck 12 via the communication radio wave. Therefore, since it is not necessary to learn a new operation, a worker who can conventionally operate and operate the hydraulic shovel can easily transmit a work signal or an alarm using the transmission device 3.

Next, a description will be given of an example in which the wireless alarm device for construction equipment according to the second embodiment of the present invention is applied to a hydraulic shovel and a dump truck, with reference to FIGS. 5 and 6. FIG. This embodiment is characterized in that the transmission means is provided with a transmission distance changing means for changing the transmission distance of the communication radio wave, and the receiving means is provided with a reception sensitivity changing means for changing the reception sensitivity of the communication radio wave. In this embodiment, the same components as those in the above-described first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

Reference numeral 21 denotes a transmitting device as transmitting means for transmitting communication radio waves, and the transmitting device 21 is provided on the hydraulic shovel 1 as a first construction machine. Further, the transmission device 21 includes an operation switch 4 provided in the cab 2 of the excavator 1 and a transmitter 5 that transmits a communication radio wave by closing the operation switch 4. The alarm switch 9 of the hydraulic excavator 1 is also used.

The above points are the same as those of the transmitting device 3 according to the first embodiment described above, but the transmitting device 21 according to the present embodiment changes the transmission output of the communication radio wave transmitted from the transmitter 5. Thus, the transmission device 3 differs from the transmission device 3 according to the first embodiment in that a transmission output adjusting unit 22 is provided as a transmission distance changing unit that changes the transmission distance of communication radio waves.

That is, the transmission output adjusting section 22 is connected to the transmitter 5 and changes the output of the communication radio wave output from the transmitter 5 when the operation switch 4 is closed. The transmission output adjustment unit 22 is adjusted, for example, by operating an adjustment knob or the like constituted by a rotary or slide type variable resistor. The adjustment knob or the like operates the hydraulic excavator 1. It is provided in the chamber 2.

Here, the transmission distance range of the communication radio wave transmitted from the transmission device 21 is formed in a substantially circular shape centering on the position Q of the excavator 1. When the output of the communication radio wave output from the transmitter 5 is increased by the transmission output adjusting unit 22, the transmission distance range of the communication radio wave is expanded. Conversely, when the output of the communication radio wave output from the transmitter 5 is reduced, the transmission distance range of the communication radio wave is narrowed.

When excavating works such as earth and sand, rocks and the like are performed jointly, a maximum transmission radius range of the communication radio wave of about 100 m around the position Q of the excavator 1 is sufficient. For this reason, by changing the transmission output of the transmitter 5 by the transmission output adjusting unit 22, the transmission distance range of the communication radio wave can be freely changed, for example, with a radius of 1 m to 100 m around the position Q of the excavator 1. You can do it.

On the other hand, reference numeral 23 denotes a receiving device as a receiving means for receiving the communication radio wave transmitted from the transmitting device 21;
The receiving device 23 includes a dump truck 1 as a second construction machine.
2 is provided. Further, the receiving device 23 is a receiver 15 for receiving the communication radio wave transmitted from the transmitting device 21.
Provided in the driver's cab 13 of the dump truck 12,
And a speaker 16 as notification means for notifying that a communication radio wave has been received.

The above points are the same as those of the receiving apparatus 14 according to the first embodiment described above, but the receiving apparatus 23 according to the present embodiment has a receiving sensitivity adjusting means for changing the receiving sensitivity of the receiver 15. The difference from the receiving device 14 according to the first embodiment is that a receiving sensitivity adjusting unit 24 is provided.

That is, the reception sensitivity adjustment unit 24 is provided with the receiver 15
The reception distance of the receiver 15 (reception area) is changed by changing the reception sensitivity of the communication radio wave. The adjustment of the reception sensitivity adjustment unit 24 is performed by operating an adjustment knob or the like constituted by, for example, a rotary or slide type variable resistor, and the adjustment knob or the like operates the dump truck 12. It is provided in the chamber 13.

Here, the receiving distance of the communication radio waves that can be received by the receiving device 23 is formed to be substantially circular with the dump truck 12 as a center. Then, when the reception sensitivity of the receiver 15 is increased by the reception sensitivity adjustment unit 24, the reception distance range of the communication radio wave is expanded. Conversely, when the receiving sensitivity of the receiver 15 is reduced, the receiving distance range of the communication radio wave is narrowed.

Further, when excavation work such as earth and sand, rocks and the like is performed jointly, the range of the communication radio wave reception range is limited to the dump truck 12.
A range with a maximum radius of about 100 m around the position is sufficient. For this reason, the receiver 15
By changing the receiving sensitivity of the dump truck 12, the receiving distance range of the communication radio wave can be freely changed within a radius of, for example, 1 m to 100 m around the position of the dump truck 12.

The wireless notification means for construction equipment according to the present embodiment has the above-described configuration, and its basic operation is the same as that according to the first embodiment.

However, in the present embodiment, the transmission distance of the communication radio wave transmitted from the transmitter 5 can be changed by providing the transmission output adjusting unit 22 in the transmission device 21, and By providing the sensitivity adjuster 24, the reception distance range of the receiver 15 can be changed.

Thus, even when a large number of construction machines such as hydraulic excavators and dump trucks are working at the work site,
By appropriately setting the transmission distance range of the transmission device 21 or the reception distance range of the reception device 23, the worker can transmit only the dump truck 12 located within a predetermined distance range from the excavator 1 via the communication radio wave. Can send work signals or alarms.

For example, as shown in FIG. 5, it is assumed that the excavator 1, the dump truck 12, and the other dump truck 31 exist at the same work site. Since the excavator 1 and the dump truck 12 work together, it is assumed that the distance between the excavator 1 and the dump truck is 50 m or less. On the other hand, since the excavator 1 and the dump truck 31 are working independently of each other, the excavator 1 and the dump truck 3
It is assumed that the distance from 1 is about 100 m.

In this case, the transmitting worker in the operator cab 2 of the excavator 1 adjusts the transmission output adjusting unit 22 to set the transmission distance range to a radius d2 (for example, 100 m) around the position Q of the excavator 1. ), The communication radio wave transmitted from the transmitter 5 reaches both the dump truck 12 and the dump truck 31 within this radius d2. Therefore, only for the dump truck 12 with which the transmitting worker works jointly,
When the alarm switch 9 is pressed in order to send a work signal or an alarm, not only is the loudspeaker 16 of the dump truck 12 beeping, but also the dump truck 31 performing unrelated work.
A warning sound may be emitted from the speaker of
Operation may be confused.

However, the transmission-side worker adjusts the transmission output adjustment section 22 to adjust the transmission distance range to the position Q of the excavator 1.
Is set at a radius d3 (for example, 50 m) with respect to the center, the communication radio wave transmitted from the transmitter 5
3 only reach the dump truck 12 inside the hydraulic excavator 1
Does not reach the dump truck 31 outside the radius d3 from the position Q. Thus, the transmitting worker working in the cab 2 of the excavator 1 can send a work signal or an alarm only to the receiving worker working in the cab 13 of the dump truck 12. it can. Accordingly, the work between the excavator 1 and the dump truck 12 can be made smoother and safer, and the work can be prevented from being confused due to the generation of an unnecessary audible alarm for the dump truck 31. .

In the above embodiments, the receiver 15 emits a buzzer sound from the speaker 16 when receiving the communication radio wave transmitted from the transmitting device 3 (21). However, the present invention is not limited to this. Instead, a configuration may be adopted in which a voice or melody digitized and stored in advance is reproduced according to a work signal.

In each of the above embodiments, when the receiver 15 receives the communication radio wave transmitted from the transmitting device 3 (21), the loudspeaker 16 emits an alarm sound, but the present invention is not limited to this. Not something. For example, a small lamp may be provided in the cab of the second construction machine, and the small lamp may be turned on when a communication radio wave is received. Furthermore, a configuration is possible in which a small lamp is turned on and an audible alarm is emitted from a speaker.

Further, in each of the above embodiments, the hydraulic shovel 1 is taken as an example of the first construction machine, and the hydraulic shovel 1 is provided with the transmitting device 3 (21).
Is not limited to a hydraulic excavator, and may be another construction machine such as a hydraulic crane, a wheel loader, a dump truck, and a truck. Further, the dump truck 12 is taken as an example of the second construction machine, and the receiving device 14 (23) is provided in the dump truck 12. However, the second construction machine is not limited to the dump truck, but may be a hydraulic shovel, a hydraulic excavator, or the like. Other construction machines such as cranes, wheel loaders, and trucks may be used.

[0065]

As described in detail above, according to the first aspect of the present invention, the transmitting means provided on the first construction machine for transmitting communication radio waves, and the transmitting means provided on the second construction machine include: Receiving means for receiving the transmitted communication radio wave,
The transmitting unit includes an operation switch provided in a cab of the first construction machine, and a transmitter that transmits a communication radio wave by closing the operation switch. Since the receiver includes the receiver for receiving the transmitted communication radio wave and the notifying means provided in the cab of the second construction machine for notifying that the receiver has received the communication radio wave, the noise Even if the worker is working at a severe work site, the work signal issued by the worker working in the cab of the first construction machine is transmitted to the second construction machine.
Can be reliably transmitted to the worker working in the cab of the construction machine.

In particular, since the notification means is provided in the cab of the second construction machine and is operated by the communication radio wave transmitted from the transmitting device, the worker can work while closing the window of the cab. In this case, the work signal can be reliably transmitted.

According to the second aspect of the present invention, since the transmission means is provided with the transmission distance changing means for changing the transmission distance of the communication radio wave, the transmission distance of the communication radio wave can be limited to a predetermined range. The communication radio wave can be transmitted only to the second construction machine within a predetermined distance range from the first construction machine. Thus, even when working with a large number of construction machines, it is possible to send work cues only to specific workers who are working directly together, and work can be performed smoothly. .

According to the third aspect of the present invention, since the receiving means is provided with the receiving sensitivity changing means for changing the receiving sensitivity of the communication radio wave, the receiving distance of the communication radio wave can be limited to a predetermined range. Only communication radio waves transmitted from the first construction machine within a predetermined distance range with respect to the second construction machine can be received. As a result, even when working with a large number of construction machines, it is possible to receive only work cues from specific workers who are working directly together and work can be performed smoothly. .

According to a fourth aspect of the present invention, the operation switch is
Since the alarm switch provided in the driver's cab of the first construction machine is also used, the communication radio wave is transmitted to the other party simply by pressing the alarm switch which has been conventionally used when sending a work signal. be able to. Thereby, the worker can transmit the communication radio wave by the operation which is more familiar than before, and the operation can be simplified.

According to a fifth aspect of the present invention, the notifying means includes a second
A speaker is provided in the operator's cab of the construction machine, and when the receiver receives a communication radio wave, a warning sound is generated from the speaker. Therefore, the noise at the work site is intense, and the operation of the second construction machine is performed. Even when the worker is working with the cabin window closed, the operator can be sure to hear the alarm in the driver's cab, and the work signal can be transmitted reliably.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a state in which a hydraulic crane and a dump truck according to a first embodiment of the present invention are working at the same work site.

FIG. 2 is a block circuit diagram showing a wireless notification device for construction equipment according to a first embodiment of the present invention.

FIG. 3 is an enlarged sectional view showing a cab of the hydraulic crane in FIG. 1;

FIG. 4 is an enlarged sectional view showing a cab of the dump truck in FIG. 1;

FIG. 5 is an explanatory diagram showing a state in which a hydraulic crane and a plurality of dump trucks according to a second embodiment of the present invention are working at the same work site.

FIG. 6 is a block circuit diagram showing a wireless notification device for construction equipment according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydraulic excavator (1st construction machine) 2,13 Operator's cab 3,21 Transmitting device (transmitting means) 5 Transmitter 9 Alarm switch 12 Dump truck (2nd construction machine) 14,23 Receiving device (receiving means) Reference Signs List 15 receiver 16 speaker (notification means) 22 transmission output adjustment unit (transmission distance changing unit) 24 reception sensitivity adjustment unit (reception sensitivity changing unit)

Claims (5)

[Claims] 1. A transmitting means provided on a first construction machine for transmitting communication radio waves, and a receiving means provided on a second construction machine for receiving communication radio waves transmitted from the transmitting means, The means comprises an operation switch provided in the cab of the first construction machine, and a transmitter for transmitting a communication radio wave by closing the operation switch, wherein the receiving means transmits from the transmitting means. And a notifying unit provided in the cab of the second construction machine for notifying that the receiver has received the communication radio wave. apparatus. 2. The construction machine radio annunciator according to claim 1, wherein said transmission means includes a transmission distance changing means for changing a transmission distance of a communication radio wave. 3. The wireless alarm device for a construction machine according to claim 1, wherein said receiving means includes a receiving sensitivity changing means for changing a receiving sensitivity of a communication radio wave. 4. The wireless alarm device for a construction machine according to claim 1, wherein the operation switch is configured to also serve as a warning switch provided in a cab of the first construction machine. 5. The system according to claim 1, wherein the notifying unit is provided with a speaker in a cab of the second construction machine, and generates an audible alarm from the speaker when the receiver receives a communication radio wave. Wireless alarm device for construction machinery.