Title:
【考案の名称】自動車の盗難等感知器
Document Type and Number:
Japanese Patent JP2585888
Kind Code:
Y2
Abstract:
An automobile theft sensor has a piezo-electric element adhered at one side to a base member and which generates a voltage in response to vibration of the automobile body, a weight adhered to the opposite side of the piezo-electric element, a silicon rubber coating covering at least a portion of the surface of the piezo-electric element and weight, a low pass filter for receiving the output voltage of the piezo-electric element and for providing an ultra low frequency signal within the range of 1-5 Hz produced by the above mentioned piezo-electric element; and a band pass filter for receiving the output voltage of the piezo-electric element and for providing a low frequency bandpass signal centered on the 30-50 Hz produced by the above mentioned piezo-electric element in response to vibration of the above mentioned automobile body. When either of the filter outputs exceeds a predetermined level it is judged that theft or tampering is occurring.
Inventors:
Keisuke Iwata
Application Number:
JP10579891U
Publication Date:
November 25, 1998
Filing Date:
November 28, 1991
Export Citation:
Assignee:
Iwata Electric Co., Ltd.
International Classes:
B60R25/10; B60R25/30; B60R25/31; B60R25/32; G08B13/00; G08B13/02; (IPC1-7): B60R25/10; G08B13/00; G08B13/02
Domestic Patent References:
| JP61135844A |
Attorney, Agent or Firm:
Shoji Yamamoto