Abstract: A contact block for an electrical switch includes an insulating housing for a pair of spaced stationary contacts. A movable contact support carrier or stroker carries a bridging member including contacts for engagement with the stationary contacts. Biasing means positioned between the stroker and the housing normally biases the carrier in the direction of a projection carried by the stroker, the stroker being actuated by a linear or rotary operator. Both normally open and normally closec contact blocks are described.

Abstract: A pushbutton linear operator for use with an electrical contact block includes a base portion, which is preferably rectangular, and a hollow cylindrical extension having external threads on an end opposite the base portion. A pushbutton having a flush, extended or mushroom cap connected to a stem is disposed in the extension. A base plate, also preferably rectangular, is integrally formed with the stem and fits within the base portion of the operator. A clamp ring is threaded to the extension to retain the cap, stem and plate in the extension and base portion of the operator. The operator is adapted to be connected to a biased contact block or biasing means may be included in the extension to "load" the pushbutton operator against a gasket for "Oil-Tite" sealing.

Abstract: A rotary operator for use with an electrical contact block includes a housing having a base portion and a hollow cylindrical extension having external threads on an end opposite the base portion, and a rotatable stem assembly disposed in the base portion and extension. The stem assembly comprises a control knob secured to one end of an intermediate member and a cam member secured to the opposite end. A clamp ring threaded to the extension retains stem assembly in the housing. Multiple position, and more particularly, two and three position cam members having novel camming surfaces are disclosed.

Abstract: A convertible switch characterized by a dielectric housing comprising a contact compartment, a pair of stationary contacts at one end of the compartment, movable contacts movable between open and closed positions, a contact carrier slidably mounted in the housing and comprising a bridging contact member upon which the movable contacts are mounted, a coil spring at one end of the contact carrier for biasing the movable contacts in one of the open and closed position, and the assembly of the contact carrier and spring being reversible within the housing compartment for holding the movable contacts in the other of the open and closed positions.

Abstract: A rotary selector switch characterized by a rotatable switch actuating unit and two switch structures, the actuating unit having a shaft with multiple sides on which a cam is detachably mounted for operation in a plurality of modes to operate the switch structures in different combinations of open and closed conditions, whereby a single cam mounted on the shaft in different positions is useful to operate the switch structures in a plurality of switch combinations.

Abstract: The device trains a user of a windsurfer board, which comprises a mill (resembling a surfboard) having a central longitudinal daggerboard (similar to a keel) and a short skeg at the stern and has a mast pivoted to the board forward of the keel carrying a sail, the tack of the sail being attached to a curved boom extending from the mast. In water, the hull pivots around the daggerboard and the skeg functions as a drag on the pivoting. The training device simulates this effect on land. The hull (with daggerboard removed) is fastened to a table supported by a vertical shaft journalled in a base supported above the ground. The shaft has a radial crank connected to two shock absorbers which are also supported by the base. The shock absorbers simulate the friction of the hull and the drag of the skeg in water.

Abstract: A phase imbalance logic module for a solid state motor protection system for a three-phase motor. Three-phase line currents are converted to corresponding voltages and rectified. The resultant output voltage is a poorly regulated DC voltage having a ripple of approximately 4% during normal operating conditions. In the event of a phase failure, even if not total, the corresponding ripple percentage increases. The phase imbalance logic network senses ripple and provides an output signal to trip a protective circuit breaker if the component of ripple becomes significantly large.

Abstract: An electrical control system which is utilized for opening a circuit breaker which is connected to a load to be protected. The control system comprises a unitary current sensor module which senses current flowing in the load to be protected. The sensor is adapted to have connected at the output thereof a load resistor which is capable of cooperating with the sensed current to provide a range of voltage over which a set of plug-in modules are operable to either provide an indication of characteristics associated with the current or the load or to provide an output function which is adapted to open the circuit breaker. The load resistor is replaceable with other load resistors so that the voltage range may be maintained even though the expected value of currents to be sensed by the sensor may change depending upon the load and other circuit characteristics.

Abstract: A long acceleration module is provided for use with a current sensor which provides an output voltage which varies with load current. There is also provided an inverse time overload logic module which controls the tripping of a circuit breaker to protect the lines in which the load current flows in relationship to the output voltage of the current sensor. The long acceleration module allows motor startup when a motor is connected to the lines to be protected. The long acceleration module purposely simulates a relatively low voltage for the input to the inverse time overload logic module during the motor startup time when high but generally non-dangerous currents are drawn by the accelerating motor.

Abstract: An indicator light circuit utilizing a single lamp and providing continuous illumination during normal operation and on and off flashing during an emergency condition. The circuit can also provide an indication wherein the lamp is continuously on but pulsating bright and dim. The indicator light circuit can thus provide four visual indications: (1) Off; (2) Normal on; (3) Flashing on and off; and, (4) On, but pulsating bright and dim. The invention is particularly adaptable for use to provide motor running and relay trip indication.

Abstract: The utilization of a Zener diode long acceleration module in conjunction with a inverse time overload module for a motor starter control system. The long acceleration module prevents the quick opening of the motor starter during the acceleration mode of an electrical motor when overload currents of relatively high magnitude are present for short periods of time in the electrical system connected to the motor. Other protective devices in the circuit will protect the system should an overload occur other than the type of overload associated with the long acceleration of a motor or similar electric device.