Abstract: A circuit breaker having an overload mechanism including an elongated bimetallic element having one end pivotally mounted in the circuit breaker housing and the other end pivotally positioned at one end of an armature element. The armature element has a latching surface engaging a trip arm to hold it in a set position. An overload current causes the bimetallic element to bend. Since the ends of the bimetallic element are constrained, its central portion moves causing the armature element to pivot disengaging its latching surface from the trip arm. The released trip arm pivots to a tripped position causing the breaker contacts to be opened.

Abstract: A circuit breaker having a pivotal movable contact arm (6) operated between open and closed positions with a stationary contact (14c) by an overcenter drive spring (8) in response to pivotal movement of a manual operating handle (4). A latch lever (10) is provided to locate the other end of the drive spring (8) and is releasable upon overload currents to carry the point of connection (10d) of the drive spring and latch lever essentially downward in line with the line of action of the drive spring to quickly reduce its force and stored energy, thereby quickly reducing the contact pressure provided thereby and enabling constriction and/or repulsion forces to separate the contacts (6c,14c). A further amount of movement of the latch lever (10) carries the point of connection (10d) of the drive spring and latch lever across the pivot plane of the movable contact arm (6) to separate the contacts. The latch lever (10) is released by a pivotally supported latch arm (12).

Abstract: A molded case circuit breaker having a movable contact arm (12) pivotally supported on a operating handle (4) and driven into and out of engagement with a stationary contact (6) by an overcenter toggle spring (28) stretched between the movable contact arm (12a) and a latch lever (14) which is releasable to carry the line of action of the spring (28) overcenter of the movable contact arm (12) to cause automatic separation of the contacts (6,10) in response to operation of a bimetal thermal overload sensing unit (18) and which has a separate magnetic overload current sensing unit (38,40) disposed on the stationary contact support (8) and isolated from the thermal overload current sensing unit (18), the magnetic sensing unit (8) operating to release an insulating wedge member (44) for movement between the circuit breaker contacts (6,10) to separate the contacts independently of the latch trip operating mechanism.

Abstract: An improved low cost relay which comprises a one-piece spool/base, a one-piece core/terminal and a one-piece yoke/armature (yokarm). A coil wound on the spool has one of its leads led to a wire which passes through the hollow stem of the spool for contact with the core upon its insertion into the stem. The stem also retains the yokarm in position with respect to the core and spool. A contact area on the yokarm moves against a contact area on a press-fit terminal mounted in the base with excellent wiping action. The other coil lead is led to a second wire mounted in the spool, and which is captured by a lanced split in a further terminal, which is also a press-fit in the base. A suppressor diode is received in the base and has one of its leads captured by the further terminal when inserted into the base, and its other lead received and captured between the yokarm and the base when the core/terminal is inserted. A backstop for the yokarm is provided by a cover for the device which is mounted on the base.

Abstract: A relay having a plunger-type armature is provided with a magnetic circuit having two serial air gaps arranged for additively applying a magnetic force to the armature in a direction substantially parallel to the longitudinal extent of its plunger to provide the requisite endwise motion to the armature. In addition to a relatively conventional air gap between the inner end of the armature and a base terminal included in the magnetic circuit, a second air gap is also provided between an armature flange and the bight of a ferromagnetic U bracket about the coil. The armature flange comprises a relatively large area extending transversely of the outer end of the armature plunger and over the U bracket bight portion. The length of the armature plunger from the underside of the flange is such that the flange comes into contiguous, but not contacting, relation with the U bracket's bight portion upon movement of the armature to its actuated position.