Patent ID: 6448880
Filing Date: 2002-09-10
Classification: H01H

Abstract:
An overload-protection push-button switch with a retractable actuating mechanism comprises:a housing; a switching circuit installed in the housing and including a first terminal, a second terminal, a first conducting leaf, and a bimetallic blade; the bimetallic blade having a movable closed end, being able to move to an overload position from a normal position in case of overload, and an open end formed with a first and a second legs for respectively connecting the first terminal and the first conducting leaf; the first conducting leaf being movable between a conduction position in which the second leg of the bimetallic blade is electrically connected to the second terminal and a broken position in which the second leg is disconnected from the second terminal; and an actuating unit installed in the housing and including: a slidable pressing stem to be actuated to one of a set and a reset positions; a positioning unit including a cantilever and a heart-shaped stepping recess and being able to position the pressing stem in the set position when the pressing stem is pressed downward; an enabling supporter provided on the housing; a rocker actuator pivotally supported on the pressing stem, having a main body formed with a nose for abutting against the first conducting leaf, and a sub-body retractably coupling to the main body and formed with a toe portion to be supported by the enabling supporter, and an abutting portion to be pushed by the closed end of the metallic blade; and an actuator-reseating member for abutting against the rocker actuator during the returning course of the pressing stem back to its reset position so that the toe portion can move into a position to be supported by the enabling supporter; whereby the toe portion could be enabled by the enabling supporter and the nose can make the first conducting leaf be alternatively located in its conduction position and its broken position in response to the location of the pressing stem in the set position and in the reset position respectively when the bimetallic blade is located in its normal position, and whereby the sub-body will retract so as to make the toe portion depart from the enabling supporter and to make the rocker actuator releases the first conducting leaf into a broken position in case of overload.