Abstract: Purging of a light beam path in an effective manner that minimizes the affect of the purging requirement on system throughput. In one embodiment, the invention is incorporated into a birefringence measurement system that has several components for directing light through a sample optical element and thereafter detecting and analyzing the light. The segment of the beam path through the sample is isolated to reduce the volume that requires continual purging.

Abstract: A circuit breaker includes a housing including a primary cover and a secondary cover having a tab; separable contacts; and an operating mechanism adapted to open and close the separable contacts. The operating mechanism includes a cradle pivotally mounted within the housing, the cradle including a latch, and a latch mechanism within the housing. The latch mechanism is adapted to capture the latch of the cradle when the separable contacts are closed. The operating mechanism also includes a rotary interlock pivotally mounted within the housing and cooperating with the latch mechanism and the tab of the secondary cover to release the latch of the cradle and to trip open the separable contacts when the secondary cover is removed from the primary cover.

Abstract: The disclosure is directed to systems and methods for precisely measuring birefringence properties of large-format samples of optical elements. A gantry-like configuration is employed for precise movement of birefringence measurement system components relative to the sample. There is also provided an effective large-format sample holder that adequately supports the sample to prevent induced birefringence therein while still presenting a large area of the sample to the unhindered passage of light.

Abstract: A circuit breaker includes a housing and an operating mechanism having a cross bar supported by a first housing surface and moving in an arcuate path between open/tripped and closed positions, a pivotally mounted cradle including a latch, and pivotally mounted primary and secondary latches. The primary latch includes a pivot, an opening and a free end. The cradle latch rests within the opening when the contacts are not tripped open. The secondary latch includes a pivot and a surface. The latches are between a second housing surface and the cross bar in a first position. The cross bar is offset from the latches in a second position. The secondary latch surface and pivot are between the second housing surface and the primary latch pivot. The secondary latch surface engages the primary latch free end when the contacts are not tripped open and maintain the cradle latch within the opening.

Abstract: Purging of a light beam path in an effective manner that minimizes the affect of the purging requirement on system throughput. In one embodiment, the invention is incorporated into a birefringence measurement system that has several components for directing light through a sample optical element and thereafter detecting and analyzing the light. The segment of the beam path through the sample is isolated to reduce the volume that requires continual purging.

Abstract: The disclosure is directed to systems and methods for precisely measuring birefringence properties of large-format samples of optical elements. A gantry-like configuration is employed for precise movement of birefringence measurement system components relative to the sample. There is also provided an effective large-format sample holder that adequately supports the sample to prevent induced birefringence therein while still presenting a large area of the sample to the unhindered passage of light.

Abstract: A molded case circuit breaker incorporates vacuum switches operated by a toggle mechanism. Pole arms tied together by a cross bar are rotated simultaneously by the toggle mechanism. A drive link translates the rotational movement of each pole arm into linear movement of a driven member along the axis of the movable electrode of the associated vacuum switch. A coupling bracket has a base section secured to the movable electrode, longitudinal sections straddling the movable electrode axis and terminal sections extending inward toward the plane of rotation of the pole arm from the ends of the longitudinal sections. Coupling members extend from the driven member through slots in the terminal sections of the coupling bracket. Springs couple the free ends of the coupling members to the coupling bracket to open and close the vacuum switch with operation of the toggle mechanism.

Abstract: A molded case circuit breaker incorporates vacuum switches operated by a toggle mechanism. Pole arms tied together by a cross bar are rotated simultaneously by the toggle mechanism. A drive link translates the rotational movement of each pole arm into linear movement of a driven member along the axis of the movable electrode of the associated vacuum switch. A coupling bracket has a base section secured to the movable electrode, longitudinal sections straddling the movable electrode axis and terminal sections extending inward toward the plane of rotation of the pole arm from the ends of the longitudinal sections. Coupling members extend from the driven member through slots in the terminal sections of the coupling bracket. Springs couple the free ends of the coupling members to the coupling bracket to open and close the vacuum switch with operation of the toggle mechanism.

Abstract: A molded case circuit breaker having current limiting capabilities optimized for relatively smaller frame sizes. More specifically, one aspect of the invention relates to a two-piece carrier assembly for carrying the main and arcing contact arms which allows the main and arcing contacts to be blown open during short circuit conditions. The two-piece carrier assembly includes an inner carrier and an outer carrier pivotally connected together. The contact arms are carried by the inner carrier. When sufficient magnetic repulsion forces are exerted on the contacts due to a short circuit condition, the inner carrier pivots relative to the outer carrier to allow the contact arms to blow open. In order to control the amount of force required for blow open, a compression spring loaded cam assembly is provided.

Abstract: A positive off mechanism for a circuit breaker includes a pair of positive off levers slideable in slots in the side plates and extendable into the path of the operating handle to prevent movement of the handle to the off position when the contacts are welded closed. The positive off levers are actuated by positive off links pivotally mounted to the side plates and coupled to the positive off levers by "dog bone" connections. The positive off links in turn are actuated by the toggle mechanism of the circuit breaker which collapses to open the contacts during normal circuit breaker operation, but which remains erect when the contacts are welded closed.

Abstract: A molded case circuit breaker having current limiting capabilities is dimensionally optimized for relatively smaller frame size circuit breakers. The handle yoke is supported with rollers thereby allowing the crossbar to be disposed in the space normally utilized for the handle yoke pivot axis. A clinch joint arcer assembly with a plurality of arcing contact arms, each pivotally connected by a clinch joint to a pivotally mounted main contact arm permits additional main contact arms to be provided in the same space normally occupied by the arcing contact arms alone. Additionally, arcing contact spring housings protect the arcing contact springs from deterioration due to corrosive ionizing gases generated during interruption. A positive off link assembly prevents the operating handle from being placed on an OFF position when the main contacts are welded together and transfers the force applied to the operating handle to the upper link to allow the weld to be broken.

Abstract: A circuit breaker having means for varying the thermal rating characterized by a circuit breaker mechanism including a releasable cradle for automatically tripping contacts to an open position in response to overload current conditions. A trip bar movable in response to movement of a bimetal element and the tie bar including a movably mounted member having an inclined surface for adjusting the spacing between the bimetal element and the movable member.

Abstract: A reverse loop circuit breaker characterized by a movable contact mounted on a contact-carrying arm movable between open and closed positions of a stationary contact that is mounted on one leg of a U-shaped conductor with another leg secured to the circuit breaker housing, an insulating block between the legs and including a pair of separable block portions having oppositely facing grooves for receiving edge portions of at least one leg to restrain its deflection, and means for securing the block portions together.

Abstract: A circuit breaker characterized by a movable contact on a contact-carrying arm movable between open and closed positions of a stationary contact mounted on one leg of a U-shaped conductor with another leg secured to the circuit breaker housing, a U-shaped brace between the legs and having a first support supporting and insulated from the other leg and having second supports on opposite sides of the one leg for retaining it against opposing repulsion magnetic forces due to current overloads.

Abstract: An electric circuit breaker with high interrupting capacity characterized by a multi-phase circuit breaker including a crossbar rotatable on its longitudinal axis and having an enlarged portion; a contact carrying arm pivotally mounted on the enlarged portion in response to an overload current at a positions paced from the axis; and a spring biased retainer contacting the arm for yieldingly retaining the arm in a contact closed position below a predetermined current rating.

Abstract: A molded case circuit breaker includes an elongated intermediate latch lever disposed between and in engagement with an intermediate latch plate and a trip bar. The intermediate latch lever is pivotable about a pivot axis and includes a first elongated portion between the latch plate and the pivot axis of a length substantially less than the length of a second elongated portion between the pivot axis and the trip bar. The intermediate latch lever so configured reduces the force required and the amount of travel of the trip bar required to effect a trip operation.