To improve a movable contact piece of a normally-closed contact which significantly affects the trip operation property of a thermal overload relay in order to secure stable quality management and a trip operation property by suppressing flection and warping deformation caused at a tip part of the movable contact piece in the manufacturing process to fix the contact.
In the thermal overload relay, a movable contact 13a facing a fixed contact 13b of the normally closed contact 13 is provided at the tip part of the movable contact piece 13c formed of a thin plate spring material (by caulking), and the movable contact piece 13c is driven to a trip operation position in linkage with a reversing mechanism which performs reversing operation in response to curving displacement of a main bimetal. Both lateral edges of the tip part of the movable contact piece 13c are subjected to bending processing to form L-shaped bent portions 13c-1, or are subjected to bead processing, whereby the rigidity of the tip part including an attachment site of the contact is enhanced.
MORISHITA FUMIHIRO
FURUHATA YUKIO
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