Abstract: A method and apparatus for improved flow control. A flow metering valve has an actuator formed of magnetic material which moves on response to an applied magnetic field to control fluid flow through the valve. A servo-control circuit receives a position command signal representative of a desired position of the actuator and produces an output command to produce a magnetic field in response thereto. The magnetic permeability of the actuator modifies the applied field and a magnetic field sensor measure the modified magnetic field to determine the position of the actuator. An actual position signal representative of the position of the actuator is negatively fed back to the servo-control circuit which produces an updated version of the output command.

Abstract: The invention both rotates and oscillates the electrode at the same time to increase the quality of materials deposited onto a substrate during an pulse fusion surfacing process. The PFS spark rate is also varied to further increase the quality and effectiveness of the PFS process. Electrode oscillation keeps the electrode from welding to the substrate surface and electrode rotation maintains even wear on the electrode work surface. An evenly worn electrode surface allows the PFS process to generate more consistent substrate surfaces. In addition, electrode oscillation neutralizes "run away" conditions and varying spark torque that occur with electrodes that are only rotated. The spark rate is varied according to various PFS process parameters (e.g., substrate material) to further improve the quality of the PFS deposition layer.

Abstract: A method for dynamically assigning addresses to new modules as they are coupled to a communication system with a synchronous data link control (SDLC) bus is described. These modules communicate with a display unit via the SDLC bus. The SDLC bus is controlled by a primary station in the display unit, with all modules acting as secondary stations. The primary station periodically broadcasts a time-tag to all modules at a thirty-two hertz rate. At power up, each module obtains a number, module 16, derived from the lower four bits of its unique twenty-four bit serial number. The module uses this number as a count of the number of time-tags which must occur before the module responds to the primary with an address request. If there are no collisions with other modules, the primary sends the module a packet which assigns the module the next available address. In the event of a collision (i.e.