JPH0416724A - Vibration detecting apparatus - Google Patents

Abstract

PURPOSE:To avoid waste of electricity when no vibration is received and to prevent consumption of a battery when the dry battery is used by turning ON a source circuit only when a piezelectric element receives vibrations, and outputting a detecting signal for a predetermined time. CONSTITUTION:When an object to be detected is vibrated, a transistor 2a of a source control part 2 is turned conductive because of the electromotive force generated to a piezoelectric element 1. Therefore, the base potential of a transistor 2b is lowered. The transistor 2a is kept conductive by a time constant circuit 2c for a time corresponding to the time constant. In other words, the source control part 2 operates as a timer to supply electricity for a fixed time, so that the voltage of a dry battery 5 is fed to an output circuit part 3 for the fixed time. As the output circuit part 3 is driven, a predetermined signal wave is generated, and the fact that the object is vibrated is informed to a receiver 6.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a vibration detection device that is turned on when vibration is detected.

<Prior art> There are various types of vibration detection devices that are configured to output a predetermined signal when vibration is detected. is also being carried out. Even in the case of this wireless type, the power is always on, and the circuitry of the device is usually in an operating state regardless of the presence or absence of vibration.

<Problems to be Solved by the Invention> Batteries, especially small-capacity dry batteries, are sometimes used as the power source for wireless devices such as those described above, and because the power is always on, the batteries are rapidly consumed. There was a problem that the cost was high due to the hassle of maintenance and the battery type.

The present invention has been made in view of these problems, and aims to provide a device that consumes less power and is suitable for use with dry batteries.

<Means for Solving the Problems> In order to achieve the above-mentioned object, the vibration detection device of the present invention includes a piezoelectric element that generates an electromotive force in response to vibration, and a piezoelectric element that is activated when the piezoelectric element generates an electromotive force. The power supply controller includes a power supply control section that turns on the power supply circuit for a preset time, and an output circuit section that operates and outputs a detection signal when the power supply circuit is turned on by the power supply control section.

When the piezoelectric element is not receiving vibration, the power supply circuit is not turned on, and it is turned on only when it receives vibration, and a detection signal is output. Therefore, no power is consumed when the piezoelectric element is not receiving vibration, and dry batteries can be used as a power source. When used, battery consumption is prevented.

<Example> Next, an illustrated embodiment will be described.

In Fig. 1, 1 is a piezoelectric element, 2 is a power supply control section, 3 is an output circuit section, 4 is a transmission (i-antenna), 5 is a dry battery for power supply,
6 is a receiver, and 7 is a receiving antenna.

The power supply control unit 2 has a first
It consists of a transistor 2a, a second transistor 2b, a time constant circuit 20 consisting of a resistor and a capacitor, etc., and the piezoelectric element 1 is installed in an appropriate manner on the object to be detected by vibration. One terminal of the transistor 2a is connected to the base of the first transistor 2a of the power supply control section 2.

The output circuit section 3 operates using a dry battery 5 as a power source, and is configured to transmit a predetermined signal radio wave from a transmitting antenna 4 to a receiver 6. and is connected to the output circuit section 3.

The receiver 6 may be configured as appropriate so that it can receive the signal radio waves from the output circuit section 3 and use the result for the desired purpose, and is generally installed in a location where commercial power is easily available. Using commercial power, the power source is kept on at all times, so that the I= radio waves can be received at any time.

This embodiment has the above-mentioned configuration, and when the object to be detected vibrates, an electromotive force is generated in the piezoelectric element 1.
The voltage causes the first transistor 2 of the power supply control unit 2 to
a becomes conductive. As a result, the base potential of the second transistor 2b decreases and the transistor 2b also becomes conductive, and this conductive state is continued for a time corresponding to the time constant by the action of the time constant circuit 2c. In other words, the power supply control unit 2 functions as a timer that supplies power for a certain period of time, and the voltage from the dry cell battery 5 is supplied for that period, the output circuit unit 3 operates, and a predetermined signal radio wave is transmitted to the target object. The receiver 6 is notified that vibration has occurred. Therefore, power is supplied from the dry cell battery 5 only during this period, and the consumption of the battery is significantly reduced compared to the case where the circuit section is operated all the time.

Next, an example will be described in which the vibration detection device of the present invention is used as a sensor for an intrusion prevention device installed at the entrance of a house or office.

FIG. 2 is a block diagram of the device, where 11 is a control device, 1
2 is a control circuit section, 13 is a receiver, 14 is a light receiver, 15 is an ultrasonic sensor I/F, 16 is an alarm unit drive circuit,
17 is a message output circuit, and 18 is a telephone I/F. The control circuit unit 12 is, for example, a ROM 12a that stores control programs and the like.

CPU 12b that performs various calculations, RAM used for calculations
12c, etc., but this does not necessarily have to be a microcomputer, and can also be constructed from a general discrete circuit.

21 is a person sensor, 22 is an insertion sensor, 23 is a door opening/closing sensor, and 24 is a lock sensor. As the person sensor 2], a sensor that can detect a person in front of the door without contact using ultrasonic waves or infrared rays can be used. In this embodiment, an ultrasonic sensor is used, for example, 40kHz.
z vibrates the transducer of the transmitter, and the receiver receives the reflection. A pulse is output every time the received waveform changes. This pulse signal is sent to the control circuit via the ultrasonic sensor I/F 15. 12.

Furthermore, the insertion sensor 22 can be used as long as it can detect that a key or something else is inserted into the keyhole of the entrance/exit door, but the vibration detection device according to the present invention is used here. .

In other words, when a suspicious person attempts to break in by inserting something into the keyhole of a door to unlock the door, it is normal for the inserted object to rattle or otherwise cause vibrations, so this abnormality may occur. It detects vibrations during operation to determine if something has been inserted into the keyhole. Therefore, the insertion sensor 22 consists of the piezoelectric element 1, power supply control section 2.
It is composed of an 8-power circuit section 3, a transmitting antenna 4, a dry battery 5, etc., and is installed inside an entrance/exit door, and the piezoelectric element 1 is fixed to the housing of a door lock or the like by an appropriate method. Further, the receiver 13 of the control section M11 corresponds to the receiver 6 in FIG.

The door opening/closing sensor 23 detects the opening/closing state of the door, and is designed to send eight-power light from a light emitting diode to the phototransistor of the light receiver 14, and detects the opening/closing state by changes in input light as the door opens/closes. be done. Further, the lock sensor 24 is a switch that detects the locked state, and is configured to detect whether or not the door is locked by turning it on and off.

16a is an alarm unit, 17a is a speaker, 25 is a telephone line, 26 is a reset switch, and alarm unit 1
6a is driven by the output of the alarm unit drive circuit 16 to issue an alarm, and at the same time the telephone I/F 18 is activated and an abnormality report is sent to a preset destination via the telephone line 25. When the reset switch 26 is turned on, the abnormality detection operation that is being executed according to the program is reset to the initial state, and the program is not executed until the reset switch 26 is turned off.

This embodiment has the configuration described above, and FIG. 3 shows a flowchart of the operating procedure.

First, in step S1, the presence or absence of a person detected by the person sensor 21 is determined, and if a person is detected, step S2
Step S3 starts the timer T1, and in the next step S3, the locked state detected by the lock sensor 24 is determined, and if the lock is in progress, the process goes to step S4. Then, the state of vibration detection by the insertion sensor 22 is determined, and if there is vibration, the process advances to step S5 to start timer T2, and in the next step S6, timer T3 is started.

Each of these timers, including a timer T4 to be described later, is built into the control circuit section 12. Timer T1 receives a pulse signal from the person sensor 21 when the person moves, so it maintains this input state for T1 time. Similarly, timer T2 inputs a pulse signal from the person sensor 21 when a vibration is detected. Since a pulse (j) is input from , this input state is held for only 12 hours. Also, timer T is set when each input condition of the person sensor 21, lock sensor 24, and insertion sensor 22 is set for a certain period of time. That is, T1
This is for determining whether or not it holds true for a certain period of time.

Next, in step S7, the count of timer T is checked, and the procedure from step S1 is repeated until time T ends. When the time T ends, since the input conditions of the sensors 21, 24, and 22 continue, it is regarded as abnormal, and the process advances to step S8 to start the timer T4. As a result, the telephone I/F 18 is activated and an abnormality report is sent to the preset destination via the telephone line 25, and at the same time, the alarm unit side circuit 16 is activated and an alarm is issued from the alarm unit 16a. The above-mentioned timer T4 is for setting the alarm output time, and the alarm continues until the count of timer T4 is confirmed in the next step S9 and time T4 ends, and when it ends, all timers are reset. Return to step Sl.

The above is the procedure when it is determined that there is an abnormality based on the inspection results of each sensor, but if no person is detected in step S1, the process proceeds to step Sll, where it is determined whether or not timer T1 is activated. If it is in the reset state, the process returns to step S1, and if it is activated, the process proceeds to step S12. While the count continues, the process returns to step 83 and subsequent steps, and when the count ends, the timer T□ is reset. It is assumed that the abnormal state has ended, and the timer T is reset in step S13. Furthermore, even when the door is not locked in step S3, it is assumed that there is no abnormality since the door has been unlocked by the legitimate owner of the key, and the process proceeds to step S13 to reset the timer T. In the next step S14, the open/closed state of the door detected by the door open/close sensor 23 is determined. If the door is closed, the process returns to step S1; if the door is open, the message output circuit 17 is activated, and a message such as "Welcome" is sent. A preset message is output from the speaker 17a, and the process returns to step S1.

Further, if no vibration is detected in step S4, the process proceeds to step S15, where it is determined whether or not the timer T2 is activated. If the timer T2 is in the reset state, the process returns to step S1, and if it is activated, the count continues. During this time, the process returns to step 86 and subsequent steps, and when the count ends, timer T2 and timer T are reset and the process returns to step S1.

Although not shown in this flowchart, as mentioned above, when the reset switch 26 is turned on, any part of the program being executed immediately returns to its initial state.
The program will not be executed until the reset switch 26 is turned off again, and the program being executed will continue to be executed as long as the reset switch 26 is not turned on.

In this device, as mentioned above, if there is a person in front of the entrance and something is inserted into the key 6 for a certain period of time, the alarm means will output an alarm signal,
It activates when the door is not yet opened and a suspicious person is attempting to enter, and reports an abnormality or threatens the suspicious person to prevent intrusion. Since the insertion sensor 22 operates only when vibration is detected, it consumes little power and can be of a wireless type using dry batteries as a power source.

<Effects of the Invention> As is clear from the above-described embodiments, in the present invention, the power supply circuit is turned on only when the piezoelectric element receives vibration, and an inspection signal is output for a certain period of time.

Therefore, when the piezoelectric element is not subjected to vibration, no power is consumed, and even when dry batteries are used as a power source, it is possible to prevent battery consumption, making it possible to install in places and applications where it is difficult to use commercial power. A suitable vibration inspection device can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of an embodiment of this invention, Fig. 2 is a block diagram of an intrusion prevention device to which this invention is applied, and Fig. 3(a)
and FIG. 3(b) is a flowchart of the operating procedure of the device. DESCRIPTION OF SYMBOLS 1... Piezoelectric element, 2... Power supply control part, 2a, 2b
...Transistor, 2c...Time constant circuit, 3...Output circuit section. 4... Transmission antenna, 5... Dry battery for power supply, 6...
・Receiver, 7...Receiving antenna, 13...Receiver,
22...Insertion sensor. Patent applicant Nishin Co., Ltd.

Claims (1)

[Claims] (1) A piezoelectric element that generates an electromotive force in response to vibration; a power control unit that operates when the piezoelectric element generates an electromotive force and turns on the power circuit for a preset time; A vibration detection device comprising: an output circuit section that operates when a power supply circuit is turned on and outputs a detection signal.