JPS62235559A - Destructive vibration detector - Google Patents

Abstract

PURPOSE:To detect separation of an object to be detected from a detector and a trouble in the detector, by providing a destructive vibration detector adapted to operate when mounted on the object being detected with a specified vibration element and a signal processing section for picking up the vibration thereof distinguishing it from destructive vibrations. CONSTITUTION:A detector 2 is mounted on an object 1 to be detected and detects destructive vibrations of the object 1 being detected with a vibration detection element 3 thereof to be outputted to a monitor 7 through a band pass filter 4 for detecting the frequency of destructive vibrations. The detector 2 is provided with a reference oscillation circuit 11 which oscillates a vibration of the frequency for self-diagnosis different from the destructive frequency and a vibrator 10 to be vibrated by the circuit 1 and a filter 14 for detecting self-diagnosing frequency and a synchronous signal 15B from the circuit 11 and a signal 15A through the vibrator 10, the object 1 being detected, the element 3 and the filter 12 are inputted into an exclusive OR gate 15. This enables the detection of the separation of the object 1 being detected from the detector 2 and a trouble in the element 3 with the unit 7.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The invention relates to a destructive vibration detector that detects the imaging frequency due to destruction and detects destruction of an object to be detected.

[Conventional technology]

A conventional breaking vibration detector will be explained using a glass breaking detector as an example. FIG. 3 shows the configuration of a conventional glass breakage detector, in which a detector 2 is fixed to the surface of glass, which is the object 1 to be detected, with adhesive or the like. The detector 2 includes a vibration detection element 3, a bandpass filter 4, an amplifier 5, and a processing circuit 6. 7 is a monitoring device.

In the above configuration, the vibration detection element 3 detects the vibration generated at 9 o'clock when the detected object 1 is broken and cut by a glass cutter, etc., and this detection signal is input to the band pass filter 4 to detect a specific vibration. Only the destructive vibration frequency is passed, and this signal is further amplified by an amplifier 5 and applied to a processing circuit 6. When the output level of the amplifier 5 exceeds a certain threshold, the processing circuit 6 outputs a breakdown alarm to the monitoring device 7. [Problems to be Solved by the Invention] However, the above-mentioned conventional breakdown vibration detector does not Since the detection method is passive, if the object to be detected 1 and the detector 2 are separated, or if the detection element 3 is defective, the object to be detected 1
There is a problem in that the monitoring device 7 cannot detect such an abnormal state when vibrations from the sensor cannot be detected.

This invention is the ninth to be made to solve the above-mentioned force problem, and it provides a destructive vibration detector capable of detecting a defective vibration detection element or separation of the vibration detection element from an object to be detected. The purpose is to obtain.

[Manual steps to solve the problem]

The destructive vibration detector according to the present invention includes a vibrating element that excites and generates a vibration different from the destructive vibration, and a vibration generated from the vibrating element and detected by the vibration detecting element through the object to be detected, which is distinguished from the destructive vibration. This is provided with a signal processing section that extracts signals separately.

[For production]

The signal processing unit according to the present invention is configured to extract the vibration generated from the vibration element and detected by the vibration detection element via the object to be detected, distinguishing it from destructive vibration. If it is separated from the object to be detected, the vibration detection element cannot detect the vibration generated from the vibration element, and this vibration cannot be extracted.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. 1st
In the figure, 12 is a pass frequency band t that does not overlap with the pass frequency band of the nopando pass filter 4 for detecting destructive vibration frequency.
-V pantone noise filter; 11 is a reference oscillation circuit that oscillates at a frequency within the pass frequency band of the bandpass filter 12; 10 is a vibration element that oscillates with the output of the reference oscillation circuit 11; 13 is the output of the bandpass filter 12. 14 is a processing circuit that processes the output of the amplifier 13;
5 is an exclusive OR gate to which the outputs of the processing circuit 14 and the reference oscillation circuit 11 are input. Other configurations are the same as before.

Next, the operation of the above configuration will be explained with reference to FIG. The vibration element 10 is attached to the surface of the object to be detected 1 like the vibration detection element 3, and is excited to vibrate by applying a self-diagnosis frequency based on the reference oscillation timing of the reference oscillation circuit 11. A synchronization signal 15B equal to the reference oscillation is output. When the device is normal and has no failure, the vibration output by the vibration element 10 at the time of outputting the reference oscillation is detected by the detection element 3 via the object to be detected 1,
This detection signal passes through the bandpass filter 12t, and an output 15A appears in the processing circuit 14. Therefore, gate 1
The output 15A of the processing circuit 14 and the reference oscillation synchronization signal 15B are applied to the gate 5, and no output appears at the gate 15. In this case, since the output of the detection element 3 has a different pass frequency band, it does not pass through the bandpass filter 4, and no output is generated in the processing circuit 6.

Next, if the detection element 3 becomes defective or the detection part 2
is away from the object 1 to be detected 1, the self-diagnosis frequency output from the vibration element 10 cannot be detected by the detection element 3, and no output appears in the processing circuit 14. This t-girl,
An output is generated at the gate 15 and a self-diagnosis abnormality signal is sent to the monitoring device 7.

On the other hand, when the detection element 3 detects destructive vibration of the detected object 1, this detection signal is input to the processing circuit 6 via the bandpass filter 4 and the amplifier 5t, and the processing circuit 6 determines that it is a destructive signal from the signal level. and sends the output to the monitoring device 7.

Incidentally, in the above embodiment, the oscillation output of the self-diagnosis frequency is made intermittent, but continuous oscillation may also be used. Further, although the destructive vibration detection frequency and the self-diagnosis frequency are separated, it is possible to differentiate them by making a difference in the detection level or detection time even if the same frequency band is used. Further, the detection element 3 and the vibration element 1o may be either an integrated package or a separate package.

〔Effect of the invention〕

As described above, according to the present invention, there is provided a vibration element that generates a vibration different from the destructive vibration of the object to be detected, and a vibration generated by the vibration element and detected by the vibration detection element via the object to be detected. A signal processing section is installed to distinguish vibration from destructive vibration and extract it.
Since the vibration caused by the vibration element cannot be detected, it is possible to detect a failure of the vibration detection element or separation of the vibration detection element from the object to be detected.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are a block diagram and a time chart showing the operation of the destructive vibration detector according to the present invention, respectively, and FIG.
The figure is a bottom view of a conventional destructive vibration detector. DESCRIPTION OF SYMBOLS 1... Object to be detected, 2... Detector, 3... Vibration detection element, 4.12... Pantone noise filter, 6.14
. . . processing circuit, 10 . . . oscillation element, 11 . . . reference oscillation circuit, 15 . . . exclusive OR gate. jll figure

Claims (1)

[Claims] (1) In a destructive vibration detector that has a vibration detection element attached to the detected object and detects destructive vibration when the detected object breaks through the vibration detection element, the It is characterized by being equipped with a vibrating element that excites and generates vibrations different from vibrations, and a signal processing unit that extracts the vibrations generated by the vibrating elements and detected by the vibration detection element via the object to be detected, distinguishing them from destructive vibrations. Destructive vibration detector.