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US 4,789,800 AGranted
Fuse, in particular for electric motors
AssigneeBraun GmbH
InventorWalter Zimmermann
Life of this patent
Estimating the term…
Abstract
The invention is directed to a fuse (1), in particular for electric motors (3), which includes a sensor (13) taking support upon the stator winding (14) of the electric motor (3), the sensor being made of a fusible material the melting of which on undue heating of the stator winding (14) causes opening of a switching device (18) connected in the supply circuit of the motor.
Claims7
In an electric motor having a housing, a stator in said housing, and a rotor mounted in said housing for rotation about a motor axis,
- thermal protection structure mounted in said housing comprising a switching device in a supply circuit of said motor, said switching device including a fixed terminal member and a resilient control member,
- lever structure pivotably mounted in said housing structure, said lever structure having a control portion at one end and a sensor portion at its opposite end, said sensor portion being made of fusible material and being seated against said stator, said control portion being in engagement with said resilient control member such that said control member is biased into engagement with said terminal member of said switching device to close said supply circuit of said motor,
- said sensor portion melting upon undue heating of said stator such that said lever structure moves and allows said resilient control member to move from a position in engagement with said switching device terminal member to open said supply circuit of said motor.
Dependencies are inferred from the claim text.