Abstract: The present invention involves a lighting kit adapted for installation into a conventional fluorescent lighting unit having a fluorescent socket and a ballast disposed in the lighting unit. At least one elongated body has fixture ends configured to engage a fluorescent socket. The elongated body supports a plurality of light emitting diodes (LEDs). A control unit, capable of receiving exterior control signals, electrically connects the LEDs to a power source for selectively dimming the LEDs, and is adapted to be mounted in place of the ballast. Dimming may be accomplished by control circuitry that recognizes repeated switching of a power source, and/or by a dipswitch on the LED device that sets the dim level. A method of retrofitting a fluorescent housing unit involves installing a LED device in the fluorescent housing unit and mounting an LED driver in the location configured to receive a conventional fluorescent ballast.

Abstract: A magnetic bearing utilizes electromagnets together with a permanent magnet to provide controlled radial and axial (thrust) load support of a shaft including a thrust disc, relative to a housing. In one form, the magnetic bearing includes an arcuate ring of high magnetic flux permeability, and a plurality of electromagnet coils circumferentially positioned about the arcuate ring which generate a radially polarized controllable electromagnetic field. A permanent magnet is spaced radially outwardly from the plurality of electromagnet coils and is linked magnetically to the shaft through both a radial air gap and an axial air gap between the housing and the shaft/thrust disc. A pair of electromagnet coils associated with the arcuate ring and circumscribing a portion of the shaft, generate an axially polarized electromagnetic field which links the shaft to the housing through the axial air gap.

Abstract: A power line communication system. The system includes at least one transmitter for generating and transmitting signals over a power line and at least one receiver for the receipt of signals transmitted over the power line. The transmitter and receiver(s) devices include a storing mechanism containing the address of the device and a programming port for electrical connection to a mating connector of a programmer. The programmer also includes a selector for selection of a desired address such that the address of the addressable device may be changed by the programmer. The transmitter also includes a timing mechanism for automatically retransmitting signals over the power line and the receiver includes a time measuring mechanism for ascertaining whether a signal has been received within a predetermined time period and a mechanism for setting the receiver in a default state should no signals be received within that time period.

Abstract: An electromagnetic thrust bearing couples a rotatable member relative to a stationary member utilizing a combination of arcuately shaped constant flux permanent magnets and controllable electromagnets, each physically associated with the stationary member. More particularly, the rotatable member comprises a shaft having a radially extending thrust disc fixed thereto. A pair of solenoids are disposed about the rotatable member in facing relation on opposite sides of the thrust disc. The facing solenoids are capable of generating a controllable electromagnetic field. A constant flux high density magnetic field is generated between the solenoid housings and the thrust disc by a pair of axially polarized arcuately shaped permanent magnets disposed on each side of the thrust disc. Each pair of permanent magnets has an inner magnet and an outer magnet radially separated from one another. Each permanent magnet is linked magnetically to the adjacent solenoid housing by respective ferromagnetic pole pieces.

Abstract: A magnetic bearing structure utilizes two adjacent electromagnetic bearings to provide controlled radial, thrust and moment load support of a shaft relative to a housing. The first bearing generates a high density controllable magnetic field to radially flux couple the shaft to the housing. A second bearing generates a high density controllable magnetic field to axially flux couple the shaft to the housing. In a preferred form, the first bearing circumferentially surrounds the shaft and includes a stator ring associated with the housing which holds several electromagnetic coils radially spaced from the shaft. Power supplied to the coils generates a radially polarized electromagnetic field surrounding the shaft. A pair of additional electromagnetic coils, or permanent magnets, circumferentially extend around the shaft to generate an axially polarized, constant flux magnetic field.

Abstract: The invention comprises a linearly actuated valve which includes a valve body, a valve seal linearly movable with respect to the body between closed and open positions, a spring and a shape memory alloy wire. The spring both biases the valve toward the closed position, and forms a part of the electrical circuit providing current to the shape memory alloy wire. The valve seal may be accurately positioned between the closed position and the open position by applying a pulse frequency modulated electrical current to the spring and the shape memory alloy wire. The electrical circuit is continuously closed and is comprised entirely of electrical conductors having no sliding electrical contacts to eliminate arcing and sparking.