Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
THERMAL RELAY
Document Type and Number:
Japanese Patent JP04109528
Kind Code:
A
Abstract:

PURPOSE: To previously control a breakage portion of a bimetallic strip to an ideal position by providing a weak point (stress concentration part) on a part or a peripheral part of radially arranged slits.

CONSTITUTION: In a bimetallic strip 2, a shaft supporting hole 2a for inserting and shaft-supporting an adjusting screw is provided on the center part and plural slits 2b-2g are provided radially from the shaft supporting hole 2a. Also a stress concentration part is provided in which a bottom surface 2c' of an optional slit 2c, coincident with neither a position on the center line X-axis connecting a pair of movable contacts 3 nor a position on the center line Y-axis orthogonal to the X-axis, is formed with a corner of R' radius smaller than a corner of R radius of the bottom surfaces 2b'-2g' of the other slits 2b-2g. When an overcurrent flows into a load connected in series, the metal 2 is heated with a heater 6, and when the metal 2 reaches a given temperature, it is reversed so that the movable contact 3 is quickly separated from a fixed contact 4 to break a circuit.


Inventors:
Shimada, Toshio
Kobayashi, Morio
Application Number:
JP1990000225051
Publication Date:
April 10, 1992
Filing Date:
August 29, 1990
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
HITACHI LTD
International Classes:
H01H61/01; G01K5/68; H01H37/54; H01H61/00; G01K5/00; H01H37/00; (IPC1-7): H01H37/54; H01H61/01