Abstract: A liquid pump system for providing liquid to a tank includes a variable-speed motor drive and a control circuit coupling the variable-speed motor drive to a power source. The control circuit has a switch that may be disposed in a state according to the amount of liquid in the tank. The control circuit provides for supplying power to the variable-speed motor drive from the power source regardless of the state of the switch. The control circuit may include a transmitter that generates a high frequency signal representative of the state of the switch. In that embodiment, a detector coupled to the variable-speed motor drive receives the high frequency signal to control operation of the liquid pump system.

Abstract: A pumping system for use in a fuel service station including one or more fuel dispensers, a fuel storage tank and conduits connecting the fuel dispensers with the tank. The pumping system comprises a variable speed pump-motor assembly for pumping fuel from the storage tank to the conduit and the dispensers, and a control connected to the pump-motor assembly for holding the fuel pressure in a preset range. Preferably the range is that required for efficient operation of a vapor recovery system, or other requirement by the EPA or by another agency, or by a service station operator. The control includes sensors which respond to the pressure in the conduits leading to the fuel dispensers. The sensors may comprise, for example, a pressure sensor in the conduit, or they may comprise power consumption sensors connected to the electrical power supply for the variable speed pump-motor assembly.

Abstract: A pumping system for use in a fuel service station including one or more fuel dispensers, a fuel storage tank and conduits connecting the fuel dispensers with the tank. The pumping system comprises a variable speed pump-motor assembly for pumping fuel from the storage tank to the conduit and the dispensers, and a control connected to the pump-motor assembly for holding the fuel pressure in a preset range. Preferably the range is that required for efficient operation of a vapor recovery system, or other requirement by the EPA or by another agency, or by a service station operator. The control includes sensors which respond to the pressure in the conduits leading to the fuel dispensers. The sensors may comprise, for example, a pressure sensor in the conduit, or they may comprise power consumption sensors connected to the electrical power supply for the variable speed pump-motor assembly.

Abstract: A pumping system for use in a fuel service station including one or more fuel dispensers, a fuel storage tank and conduits connecting the fuel dispensers with the tank. The pumping system comprises a variable speed pump-motor assembly for pumping fuel from the storage tank to the conduit and the dispensers, and a control connected to the pump-motor assembly for holding the fuel pressure in a preset range. Preferably the range is that required for efficient operation of a vapor recovery system, or other requirement by the EPA or by another agency, or by a service station operator. The control includes sensors which respond to the pressure in the conduits leading to the fuel dispensers. The sensors may comprise, for example, a pressure sensor in the conduit, or they may comprise power consumption sensors connected to the electrical power supply for the variable speed pump-motor assembly.

Abstract: A pumping system for use in a fuel service station including one or more fuel dispensers, a fuel storage tank and conduits connecting the fuel dispensers with the tank. The pumping system comprises a variable speed pump-motor assembly for pumping fuel from the storage tank to the conduit and the dispensers, and a control connected to the pump-motor assembly for holding the fuel pressure in a preset range. Preferably the range is that required for efficient operation of a vapor recovery system, or other requirement by the EPA or by another agency, or by a service station operator. The control includes sensors which respond to the pressure in the conduits leading to the fuel dispensers. The sensors may comprise, for example, a pressure sensor in the conduit, or they may comprise power consumption sensors connected to the electrical power supply for the variable speed pump-motor assembly.

Abstract: This disclosure relates to a liquid supply system including a motor-pump unit designed for installation in a liquid supply such as a well or storage tank. The unit supplies the liquid to a supply pipe, and a pressure sensor connected to the pipe is operable to provide a control signal representative of the liquid pressure in the pipe. The motor is a variable-speed AC motor. A control for the motor is responsive to the control signal and actuates a power circuit to drive the motor at a speed adjusted to maintain the liquid pressure at a substantially constant value. The control circuit further includes means for turning off the power to the motor in the absence of flow through pipe, which does not require a flow sensor. The power circuit comprises a DC link including a rectifier and an inverter. The rectifier is located adjacent the pressure sensor; the inverter may be located adjacent the rectifier and the pressure sensor or in the casing of the motor-pump unit.

Abstract: An alternator for repetitive pulsing of an electromagnetic projectile launcher is provided with a stator structure having at least one pair of single layer concentric coil portions which are electrically connected in parallel. A rotating magnetic field induces a voltage in these coil portions without producing circulating currents. The alternator is connected through a switch to a pair of genrally parallel conductive projectile launching rails and a sliding conductive armature between the rails. By causing the switch to conduct at a predetermined phase angle, the voltage across the launching rails can be reduced to zero as the projectile leaves the rails. Where a succession of projectiles is to be fired, the phase angle at which the switch begins to conduct is controlled in order to achieve a substantially constant muzzle velocity for each projectile while minimizing the rail voltage as each projectile exits the rails.