JP3514327B2 - Helmet mounting alarm - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alarm device suitable for use with a disaster prevention helmet. 2. Description of the Related Art In order to ensure the safety of a working environment, an alarm device incorporating gas detecting means and radiation detecting means is attached to clothing, and when a predetermined standard is exceeded, sound or light is emitted. For example, an alarm device for notifying a worker of danger has been proposed. However, there is a problem that a warning is missed due to a masking effect due to the noise in a work site where the noise is loud. In order to solve such a problem, a method of transmitting a warning signal to a worker via earphones has been taken. However, there is a problem that the user forgets to attach the device or gets in the way. [0003] The present invention has been made in view of such a problem, and an object of the present invention is to reliably operate an alarm signal without receiving a masking effect due to noise. The purpose of the present invention is to provide a new alarm device that can be transmitted to a person. In order to solve such a problem, the present invention operates according to a signal from a means for detecting an external environment , and resonates with a helmet having an oscillation frequency from the outside. Frequency adjustment to adjust to frequency
An audio frequency oscillating means provided with a helmet , a sounding means operated by a signal from the audio frequency oscillating means, and an operating power supply are housed in a housing having a projection which makes point contact with the helmet.
As well as was the case in so that such comprises a fastening means by the elastic force by contacting the protrusions to the helmet. The frequency of the audible frequency oscillating means is adjusted to a maximum volume when mounted on a helmet. As a result, since the helmet vibrates at the self-resonant frequency, the alarm sound is transmitted to the wearer not only as sound but also in conjunction with the skull transmission through the helmet, so that it can be clearly recognized regardless of noise or the like. . BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention. FIG. 1 shows an embodiment of the present invention. In the drawing, reference numeral 1 denotes a housing for accommodating an alarm circuit to be described later, which can be opened and closed by a lid 1a, and a sounding means 9 such as a piezoelectric buzzer. A fixing device 2 made of an elastic material for elastically fixing to the edge of the helmet H is attached to the back surface thereof, which accommodates a signal processing means to be operated and a battery as a driving power source. FIG. 2 shows an embodiment of the above-mentioned alarm circuit. In the drawing, reference numeral 5 denotes a comparison circuit, which is a detecting means 6 for detecting a dangerous state such as a gas sensor or a radiation sensor.
Is compared with a preset reference value, and a signal is output when the reference value is exceeded. Reference numeral 7 denotes a variable frequency oscillation circuit, which is an oscillation frequency regulating element which can be operated from the outside. In this embodiment, the frequency is set by a variable resistor 8, and when the signal is output from the comparison circuit 5, the audio frequency signal is converted to a piezoelectric signal. It is configured to output to a sounding means 9 such as a buzzer. In addition, reference numeral 10 in the drawing indicates a battery serving as a driving power supply. In this embodiment, when the edge of the helmet H is inserted into the opening of the fixing device 2 and inserted into the back against the elastic force of the fixing device 2, the housing 1 is connected to the helmet H at one point. Elastically fixed in a state of contact with When a pseudo signal is input to the variable frequency oscillation circuit 7 to activate the sound generating means 9, the vibration of the sound generating means 9 is emitted as sound into the air and transmitted to the helmet H via the housing 1 at the same time. . When the variable resistor 8 is adjusted in this state, the frequency of the signal of the variable frequency oscillator 7 changes.
The vibration of the sound generator 9 resonates with the helmet H. In this state, the frequency is fixed and the case lid 1a of the housing 2 is closed. FIGS. 4 (a), (b) and (c) respectively show a vibration characteristic diagram of one safety helmet, a frequency characteristic diagram of the sounding means 9 of the above-mentioned alarm device, and an alarm device in the safety helmet. FIG. 4 is a diagram showing acoustic characteristics when the safety helmet is attached, and shows one resonance frequency f0 (about 2100H
When the vibration frequency of the alarm device coincides with z), FIG.
As shown in (1), the signal is amplified to an extremely large level. When the worker wears the helmet 1 and works, when the alarm device 3 is activated, the vibration of the sound generator 9 propagates through the air and is recognized by the auditory sense. Since it resonates with H, it is also transmitted to the skull of the wearer via the helmet H, so that both can clearly recognize the alarm. Of course, the sound from the sound generating means 9 propagates in the air, so that in an environment where noise is not severe, other people around can recognize the sound by hearing. FIG. 5 shows a second embodiment of the present invention.
In the figure, reference numeral 12 denotes a housing, and a projection 13 is formed at a position where it contacts the helmet. According to this embodiment, since the casing 12 forms a point contact with the helmet H by the projection 13, the contact state between the casing 12 and the helmet H can be always kept constant. Thus, the vibration of the sound generator 9 can be surely resonated with the helmet H. According to the present invention as described above ,
When an alarm signal is output and the sounding means is activated, the vibration of the sounding means resonates with the helmet, so that the warning can be clearly recognized in conjunction with the skull transmission through the helmet, and the signal transmitting means such as earphones is used. Without doing
The noise masking effect can be reduced as much as possible, and the alarm signal can be reliably transmitted to the wearer.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of the present invention. FIG. 2 is a block diagram showing an embodiment of an alarm means housed in a housing of the above device. FIG. 3 is a diagram showing a state in which the device is mounted on a helmet. FIGS. 4A, 4B, and 4C are diagrams showing the self-vibration characteristics of the helmet, the acoustic characteristics of the sounding means, and the acoustic characteristics when the sounding means is mounted on the helmet, respectively. . FIG. 5 is a view showing another embodiment of the present invention. [Description of Signs] 1 Housing 2 Fixture H Helmet

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Claims (1)

(57) [Claim 1] An audio frequency which is operated by a signal from a means for detecting an external environment and has frequency adjusting means for externally adjusting an oscillation frequency to a frequency which resonates with a helmet. Oscillating means, a sound generating means operated by a signal from the audio frequency oscillating means, and an operating power supply, housed in a housing having a projection that makes point contact with the helmet,
A helmet mounting alarm device, comprising: a fixing means for bringing the housing into contact with the projection with the helmet by elastic force.