Abstract: A valve sizer for determining an appropriate replacement valve size when performing a heart valve replacement procedure is provided. In one version the valve sizer has a hollow shaft with proximal and distal ends. A movable sizing element couples to the distal end of the shaft and is radially expandable between first, contracted and second, expanded positions. An actuator assembly on a handle includes an actuator coupled to a clutch member via a ball-spring-detent clutch. A rod extends through the shaft and maintains a fixed distance between the handle and a distal hub in the sizing element. Movement of the actuator causes axial movement of the shaft, thereby causing radial expansion of sizing petals relative to the hub. The clutch slips when a predetermined reaction force from the surrounding valve annulus is met by the petals.

Abstract: A thermomagnetic trip is disclosed for an electrical switching device, especially a circuit breaker. In at least one embodiment it includes at least one first and one second terminal, a first heating element, a conductor able to be influenced by temperature, a yoke and a clapper armature. A current path is formed through at least the first terminal, the conductor, the first heating element and the second terminal. The current path is disposed at least in sections on and/or in the yoke such that a magnetic field acting on the clapper armature is induced in the yoke by the current flowing through the current path and wherein a second heating element is disposed in the current path especially between the first terminal and the conductor.

Abstract: An exemplary mechanically operated switching device includes at least one movable contact and an operating mechanism for coupling/separating the movable contact to/from a corresponding fixed contact. The operating mechanism includes first elastic mechanism for, upon release, providing the energy to separate the movable and fixed contacts. At least one shunt release having: a member movable between first and second stable positions, wherein movement from the first stable position to the second stable position releases the first elastic mechanism; at least a permanent magnet generating a force for holding the movable member in the first stable position, wherein the movable member held in the first stable position compresses a second elastic mechanism; and at least one electrical winding associated with the movable member and the electronic mechanism, which is configured to electrically drive the winding to generate a magnetic force that releases of the compressed second elastic mechanism.

Abstract: An electrical appliance designed according to the principle of a fork connection, and into which a contact element is insertable between two contact clips. In the event of high currents, such as those which can occur in the event of short circuits in a load which is connected to the fork connection, magnetic forces counteract current constriction forces, thus allowing higher currents to be carried through the connection without the contact clips being bent apart from one another in the process. This is achieved in that a magnetic field caused by a current is concentrated in a particularly advantageous manner for production of forces which draw the two clip contacts together with the aid of a part at least partially composed of a ferromagnetic material, one of which in at least one embodiment, is arranged between the contact clips.

Abstract: An electromechanical/solid-state AC relay has an electromechanical winding coil that moves an armature to force mechanical contacts to open or close. Electrical arcing across the mechanical contacts that occur as the contacts are opening or closing can damage and severely reduce the lifetime of the relay. Contact arcing is prevented by pulsing a triac on for a short period of time just before and after the mechanical contacts make or break contact. The triac limits the voltage difference across the mechanical contacts to less than one volt to prevent arcing. The triac is turned off after the mechanical contacts finish moving, reducing the heating and average power through the triac. A zero-sampling circuit that detects when the AC input voltage switches across 0 volts and activates a control integrated circuit to switch on the triac during zero-crossings to minimize power surges.

Abstract: A spring assembly is provided for a yoke assembly of an electrical switching apparatus including a housing, separable contacts enclosed by the housing, and an operating mechanism structured to open and close the separable contacts. The operating mechanism includes a pole shaft. The yoke assembly is coupled to the pole shaft and is movable among first and second positions corresponding to the separable contacts being closed and open, respectively. The spring assembly includes a number of first springs having a first spring rate and being coupled to the yoke assembly, and a number of second springs having a second spring rate and being coupled to the yoke assembly. The second spring rate is different than the first spring rate. The number of first springs and the number of second springs bias the yoke assembly toward the second position.

Abstract: A highly efficient electromagnetic actuator which can reduce leakage of the magnetic flux is provided. The electromagnetic actuator comprises a first coil 31, a movable body 2 adapted to move on the central axis of the first coil 31, a first stator 11 covering the top face, bottom face and outer peripheral face of the first coil 31, and a permanent magnet 15 adapted to firmly latch the movable body 2 at one end point of its movable range. A second stator 12 adapted to control the magnetic flux generated from the permanent magnet 15 is provided in succession with the first stator 11. By providing the second stator 12, when releasing the movable body 2 from its firmly latched state, the permanent magnet 15 is not inversely excited or demagnetized.

Abstract: The present invention relates to a family of resettable circuit interrupting devices that eliminates the need to rewire a resettable circuit interrupting device after it is installed and powered up to correct for a reverse wiring conditions.

Abstract: A contact spring assembly is provided for an electrical switching apparatus including a movable contact assembly and a stationary contact assembly having stationary electrical contacts. The movable contact assembly includes a carrier assembly, and movable contact arms pivotably coupled to the carrier assembly and carrying movable electrical contacts. The contact spring assembly includes a first contact spring housing member, a second contact spring housing member coupled to and disposed opposite from the first contact spring housing member, a spring guide disposed between and coupled to at least one of the first and second contact spring housing members and including spring holes, springs received in the spring holes, and sliders coupled to the springs. The springs and sliders individually bias the movable contact arms and movable electrical contacts toward engagement with corresponding stationary electrical contacts. A movable contact assembly and an electrical switching apparatus are also disclosed.

Abstract: An electrical switching apparatus accessory sub-assembly is for an electromagnetic coil including a movable stem. The electrical switching apparatus accessory sub-assembly includes a coil frame having a first end and an opposite second end. A housing includes a plurality of interior surfaces, a first end and an opposite second end. The second end of the housing has an opening structured to receive the movable stem of the electromagnetic coil. A number of the interior surfaces of the housing are structured to selectively hold the coil frame in either one of a first position in which the coil frame first end faces the housing first end and the coil frame second end faces the housing second end, and a second position in which the coil frame first end faces the housing second end and the coil frame second end faces the housing first end.

Abstract: A shunt assembly is provided for an electrical switching apparatus including a conductor assembly having a load conductor and a movable contact assembly with a number of movable contact arms. The movable contact assembly is movable in response to a fault current. The shunt assembly includes a number of flexible conductive elements each having a first end electrically connected to the load conductor, a second end electrically connected to a corresponding one of the movable contact arms, and a number of bends disposed between the first and second ends. At least one constraint element is disposed proximate a corresponding one of the bends and constrains movement of the flexible conductive element in response to the fault current, thereby translating the magnetic repulsion force associated with the fault current into a corresponding torque of the movable contact arms of the movable contact assembly.

Abstract: A circuit breaker including an overload trip mechanism having a current sensitive element forming a first load current conductive path. The trip mechanism is activated in response to a predetermined level of current through the trip current path. A multiple pole switch unit selectively connects a plurality of shunt load current conductive paths of various resistance values in parallel with the trip current path. The switch is operated by a cam member externally insertable into the circuit breaker in any one of a plurality of camming positions which set the switch unit to provide selected shunt current paths. Removing of the cam from the circuit breaker activates an interlock for automatically tripping the breaker. An alternative embodiment is presented wherein a contact switch unit connects, through a selectable resistance element, a shunt load current conductive path in parallel with the trip current path. The contact switch is activated by a resistance element externally insertable into the circuit breaker.