Circuit breaker
AssigneeWestinghouse Electric Corp.
InventorsAlfred E. Maier, William I. Stephenson, Jr.
Life of this patent
Estimating the term…
Abstract
A molded case circuit breaker having thermal and magnetic trip means. A moving contact support structure is disposed about the magnetic trip means so as to cause current flowing through the circuit breaker contacts to pass twice through the magnetic circuit of the magnetic trip means. The moving contact support structure includes resistance material operable upon overcurrent conditions through the contacts to aid in heating the thermal trip means. An operating mechanism includes an operating spring in compression which acts as one leg of a toggle linkage and stores energy to operate the contacts with a snap action.
Claims12
A circuit breaker, comprising:
- an insulating housing;
- an operating handle having open, closed, and trip positions;
- a latch lever;
- means pivotally attaching said latch lever to said housing;
- a stationary contact;
- a moving contact assembly pivotally attached to said latch lever, said moving contact assembly comprising a moving contact cooperable with said stationary contact to open and close an electric circuit;
- an operating spring having one end pivotally connected to said moving contact assembly and having another end engaged by said operable handle;
- a latch member attached to said moving contact assembly and releasably engaging said latch lever, release of said latch lever allowing said moving contact assembly to pivot with respect to said latch lever, said pivoting movement causing said moving contact to separate from said stationary contact and open an electric circuit;
- and
- trip means operable upon overcurrent conditions through said moving and stationary contacts to effect automatic release of said latching lever by said latching member;
- actuation of said operating handle between open and closed position being operable to pivot said latch lever and said moving contact assembly and cause said moving contact to cooperate with said stationary contact to open and close an electric circuit.
A circuit breaker, comprising:
- an insulating housing;
- separable contacts comprising a stationary contact and a moving contact;
- an operating handle to open and close said contacts;
- releasable means operable upon actuation to automatically open said contacts;
- thermal trip means operable upon overcurrent conditions through said contacts to actuate said releasable means;
- and
- a contact arm supporting said moving contact, said contact arm comprising resistance material operable upon overcurrent conditions through said contacts to heat said thermal trip means;
- said thermal trip means comprising a bimetal element generally parallel to and separate from said contact arm;
- heat produced by said resistance material upon overcurrent conditions through said contacts causing said bimetal element to deflect and actuate said releasable means.
A circuit breaker, comprising:
- an insulating housing;
- separable contacts disposed in said housing and comprising a stationary contact and a moving contact;
- an operating handle to open and close said contacts;
- releasable means operable upon actuation to automatically open said contacts;
- magnetic trip means operable upon overcurrent conditions through said contacts to actuate said releasable means, said magnetic trip means including a magnetic circuit;
- and
- a contact support structure disposed about said magnetic trip means so as to cause current flowing through said contacts to pass twice through said magnetic circuit.
Dependencies are inferred from the claim text.