JP2011158984A5

JP2011158984A5 -

Info

Publication number: JP2011158984A5
Application number: JP2010018269A
Authority: JP
Filing date: 2010-01-29
Publication date: 2012-09-27
Anticipated expiration: 2030-01-29

Description

本発明に係る音響警報装置によれば、コイルへの通電時間を調整するオン／オフ動作の周波数を変化させる。一般に、圧電ブザーは、最大音圧を得ることのできる駆動周波数は固体によってばらつきがあり、圧電ブザーを最大音圧で鳴動させるためには個別に適宜に周波数調整を行う必要がある。しかし、本発明に係る音響警報装置によれば、周波数を変化させるので、個別に周波数調整を行わなくとも最大音圧で圧電ブザーを鳴動させることができる。
また、本発明に係る音響警報装置によれば、コイルへの通電時間を調整するオン／オフ動作の周波数を変化させるとともに、デューティー比を変化させるようにした。このため、低周波数で駆動している際にコイルに通電する時間を短くすることができ、消費電流を低減させることができる。 According to the acoustic alarm device of the present invention, the frequency of the on / off operation for adjusting the energization time to the coil is changed. In general, the drive frequency with which the piezoelectric buzzer can obtain the maximum sound pressure varies depending on the individual, and in order to cause the piezoelectric buzzer to ring at the maximum sound pressure, it is necessary to individually adjust the frequency appropriately. However, according to the acoustic alarm device of the present invention, since the frequency is changed, the piezoelectric buzzer can be sounded with the maximum sound pressure without adjusting the frequency individually.
In addition, according to the acoustic alarm device of the present invention, the frequency of the on / off operation for adjusting the energization time to the coil is changed, and the duty ratio is changed. For this reason, it is possible to shorten the time for energizing the coil when driving at a low frequency, and to reduce the current consumption.

制御回路３１は、火災受信機ＦＡから音響鳴動の制御信号を受信すると、所定の周波数でトランジスタ３５をオン／オフさせて、コイル３３に所定の周波数で電圧を印加する。そして、トランジスタ３５をオフしたときにコイル３３に発生した昇圧電圧を圧電ブザー３２に印加することにより、圧電ブザー３２を鳴動させる。
ここで、最大音圧を得ることのできる圧電ブザー３２の駆動周波数は、各個体でばらつきがある。圧電ブザー３２の個体毎の特性に合わせて駆動周波数を調整すれば、それぞれの圧電ブザー３２が最大音圧で鳴動することができるが、個体ごとに調整するには手間がかかり、多大なコストがかかる。また、設置箇所の温度条件等によっても、最大音圧を得ることのできる圧電ブザー３２の駆動周波数が変化しうるので、たとえ調整したとしても最大音圧を得られるとは限らない。
このため、制御回路３１は、トランジスタ３５をオン／オフさせる周波数、すなわち、圧電ブザー３２に印加する電圧の周波数を所定の範囲でスイープさせる。例えば、２．５ｋＨｚ、２．６ｋＨｚ、２．７ｋＨｚ、・・・、３．５ｋＨｚ、のように、０．１ｋＨｚ刻みで１０ｍｓｅｃずつ電圧を印加し、その周波数で圧電ブザー３２を鳴動させる。このように、印加する電圧の周波数を所定の範囲でスイープさせることで、いずれかのタイミングで最も大きい音圧レベルで音響鳴動させることができる。なお、トランジスタ３５は、電流制限手段３４のオン／オフするスイッチとして動作するとともに、電流制限手段３４の構成部品としても兼用されているため、部品点数を削減することができ、コストにおいて優れる。 When receiving the acoustic ringing control signal from the fire receiver FA, the control circuit 31 turns on / off the transistor 35 at a predetermined frequency and applies a voltage to the coil 33 at the predetermined frequency. The boosted voltage generated in the coil 33 when the transistor 35 is turned off is applied to the piezoelectric buzzer 32 so that the piezoelectric buzzer 32 sounds.
Here, the driving frequency of the piezoelectric buzzer 32 capable of obtaining the maximum sound pressure varies among the individual. If the drive frequency is adjusted in accordance with the characteristics of each individual piezoelectric buzzer 32, each piezoelectric buzzer 32 can ring at the maximum sound pressure. Take it. Further, since the drive frequency of the piezoelectric buzzer 32 that can obtain the maximum sound pressure can be changed depending on the temperature condition of the installation location, the maximum sound pressure is not always obtained even if it is adjusted.
Therefore, the control circuit 31 sweeps the frequency at which the transistor 35 is turned on / off, that is, the frequency of the voltage applied to the piezoelectric buzzer 32 within a predetermined range. For example, a voltage is applied in increments of 0.1 kHz, such as 2.5 kHz, 2.6 kHz, 2.7 kHz,..., 3.5 kHz, and the piezoelectric buzzer 32 is caused to ring at that frequency. In this way, by sweeping the frequency of the voltage to be applied within a predetermined range, it is possible to sound the sound with the highest sound pressure level at any timing. The transistor 35 is configured to operate as a switch for turning on / off of the current limit means 34, because it is also used as a component of the current limiting means 34, it is possible to reduce the number of components, excellent in cost.

上述したように、本実施の形態１に係る音響警報装置Ｃ１１によれば、電流制限手段３４によりコイル３３に流れる電流を制限することができる。また、コンデンサ２３により、圧電ブザー鳴動回路３０が消費する電流のピークを抑えて平均化することができる。さらに、電流制限回路２２より、圧電ブザー鳴動回路３０に流れる電流を制限することができる。 As described above, according to the acoustic alarm device C11 according to the first embodiment, the current flowing through the coil 33 can be limited by the current limiting means 34. Moreover, the capacitor 23 can suppress and average the current peak consumed by the piezoelectric buzzer sounding circuit 30. Further, the current flowing through the piezoelectric buzzer sounding circuit 30 can be limited by the current limiting circuit 22.

このように、本実施の形態２に係る音響警報装置によれば、コイル３３に印加する電圧のデューティ比を変化させるようにした。このため、圧電ブザー３２の音圧レベル上昇に寄与しない電流が流れるのを抑制することができるので、消費電力を低減することができる。 Thus, according to the acoustic alarm device according to the second embodiment, and so as to vary the duty ratio of the voltage applied to the coil 3 3. For this reason, since it can suppress that the electric current which does not contribute to the sound pressure level rise of the piezoelectric buzzer 32 flows, power consumption can be reduced.

Claims

A piezoelectric buzzer,
A coil connected in parallel to the piezoelectric buzzer;
Switching means for adjusting energization time to the piezoelectric buzzer and the coil;
Control means for controlling on / off operation of the switching means;
An acoustic alarm device comprising: the coil connected in parallel; and a current limiting unit connected in series to the piezoelectric buzzer to limit a current to the coil.

A piezoelectric buzzer,
A coil connected in parallel to the piezoelectric buzzer;
A current limiting means for adjusting an energization time to the piezoelectric buzzer and the coil, and to limit a current to the coil during energization;
Control means for controlling the on / off operation of the current limiting means.

The current limiting means includes
The acoustic alarm device according to claim 2, comprising an emitter follower circuit including a transistor and a resistor connected to an emitter side of the transistor.

The acoustic alarm device according to any one of claims 1 to 3, wherein the control means changes a frequency of an on / off operation.

The acoustic alarm device according to claim 4, wherein the control unit changes a duty ratio of the on / off operation.

A fire receiver,
The sound alarm device according to any one of claims 1 to 5 , which is connected to the fire receiver via a signal line that is a signal transmission / reception route,
The sound alarm device sounds sound based on a control signal transmitted from the fire receiver.

A fire receiver,
A plurality of acoustic alarm devices according to any one of claims 1 to 5 , which are connected to the fire receiver via a signal line serving as a signal transmission / reception route,
The plurality of sound alarm devices sound intermittently and synchronously between the plurality of sound devices based on a control signal transmitted from the fire receiver.