Title:
CLOSED SWITHBOARD
Document Type and Number:
Japanese Patent JPH03295428
Kind Code:
A
Abstract:
PURPOSE:To improve the accuracy and to make the device inexpensive by fitting a sound generation source which generates a sound when a conductor exceeds certain set temperature, and providing a detecting machine which detects the generated sound and a measuring instrument which measures the generated sound. CONSTITUTION:Shape memory alloy 6 is fitted in the place of the conductor whose temperature rise is to be measured. This metal is rectangular and recessed downward hemispherically at the center part below the set temperature, but the hemspherically recessed part of the center part deforms upward to generate the sound at this time. If overheating occurs at a measurement point, the alloy 6 generates the sound, which is sensed by one microphone 9 fitted on each surface of the closed switchboard 1 and inputted to the measuring instrument 4 to generate a warning output 5. Consequently, the switchboard accurately operates for the set temperature and the accuracy can be improved.
Inventors:
AMANO YOSHIKI
NAGAO KENJI
NAGAO KENJI
Application Number:
JP9863490A
Publication Date:
December 26, 1991
Filing Date:
April 13, 1990
Export Citation:
Assignee:
MITSUBISHI ELECTRIC CORP
International Classes:
G01K5/48; G01K11/22; (IPC1-7): G01K5/48; G01K11/22
Attorney, Agent or Firm:
Hiroshi Murakami (1 outside)