Abstract: An Integrated controller for a commercial vehicle air conditioning system according to the present invention includes a central control unit in communication with a high-pressure switch or sensor, a low-pressure switch or sensor, and an evaporator thermostat. The central control unit includes outputs that control the air conditioning system compressor and fan according to the conditions detected by the high pressure switcher sensor, the low pressure switch or sensor, and the evaporator thermostat.

Abstract: A load center has an enclosure provided with a back wall and a swingable access door, a bus panel secured within the enclosure and a plurality of circuit breakers mounted to the bus panel for switching power between an electrical utility and an auxiliary power source. The load center includes an input receptacle for receiving a plug connector of the auxiliary power source and transferring auxiliary power to the bus panel and the circuit breakers. A pair of watt meters are connected to the input receptacle for monitoring the power transferred from the auxiliary power source. A mounting framework incorporates the input receptacle and the watt meters within the enclosure on the back wall.

Abstract: A flow control device to control the rate of flow of granular material or the like therethrough has a valved inlet to control the ingress of material into the flow control device. A flowmeter is downstream of the valved inlet to receive the material and detect the rate of flow thereof. The material travels along a generally steep path between the valved inlet and the flowmeter. The flowmeter includes a guide to collect the material into a generally coherent stream and redirect the stream from the generally steep path to a generally horizontal path. A controller is responsive to the flowmeter and controls the valved inlet so that the rate of flow of material through the flow control device is at or near to a desired rate.

Abstract: An apparatus and method for aiming a vehicle headlight to a standard image pattern includes a frame movable relative to the vehicle. A housing carried on a vertically adjustable housing includes a lens focusing a headlight beam onto a reflective screen which reflects the beam image to a camera. A control compares the digitized image output from the camera with a standard image pattern and generates a correlation factor based on the difference between the reflected image and a standard image. Based on the difference, the control generates output signals to an adjustment device engagable with the headlight mounting frame to adjust the position of the mounting frame to reduce the difference to zero.

Abstract: A thermal relief valve for a gas cylinder has a body with an inner wall defining a passageway for flow of fluid between inlet and outlet. A piston within the bore moves between a first position arresting flow from inlet to outlet, and a second position permitting flow from inlet to outlet. A restricting assembly for arresting movement of the piston towards the second position includes a thermal sensitive element of suitable eutectic material at the bore inner wall, with protrusions defining a first camming surface, and two or more restricting elements defining a second camming surface positioned to engage the first camming surface.

Abstract: A control valve is provided for a water conditioning system having a mineral tank. The control valve includes a housing having an upper body portion and a lower body portion. The housing defines a chamber located between the upper and lower body portions. The upper body portion includes a first upper port, a second upper port, and a third upper port. The lower body portion includes a first lower port, second lower port, and a third lower port which provide fluid communication with the tank. A cylindrical disk is located within the chamber and is selectively rotatable about a central axis. The disk includes an upper face having a generally centrally located aperture and a peripherally located aperture. The disk also includes a spaced apart lower face having a first peripherally located aperture and a second peripherally located aperture. A first fluid passage extends through the disk between the centrally located aperture in the upper face and the first peripherally located aperture in the lower face.

Abstract: A microprocessor controlled automatic transfer switch is provided with an improved voltage sensing scheme which utilizes an open-delta transformer and a control routine for determining voltage level or phase loss. The invention requires only two transformers for sensing three-phase power. An actuator protection feature is also provided to limit the duration of power applied to and to protect the actuator solenoids on the automatic transfer switch. Also provided are improved diagnostic annunciation features which provide specific information regarding switch position and sensing element and/or actuator malfunction.

Abstract: A high-speed constant-horsepower motor includes a rotor and a stator having a plurality of groups of windings which are separately driven. In one mode of operation, the polarity of the voltage applied to each winding is such that the windings behave as distinct electromagnets, each defining a separate magnetic pole. In another mode of operation, the polarity of voltage applied to some of the windings is reversed, such that pairs of adjacent windings behave as single electromagnets. In the latter mode, the effective number of magnetic poles is reduced by a factor of two. Thus, the effective number of magnetic poles of the motor can be varied electronically, even while the motor is operating. The invention makes it possible, in one example, to operate the motor as an eight-pole motor at low speeds, and as a four-pole motor at high speeds. The effective motor constants are changed appropriately from eight-pole to four-pole modes.

Abstract: An apparatus for controlling the speed of an induction motor includes a first winding and a second winding. The first winding and second winding are adapted to be coupled to an AC source for supplying an AC input signal. A first switching device is coupled to the first winding and a second switching device is coupled to the second winding. Each of the switching devices is operative in a low impedance state enabling current to flow through the associated winding of each switching device and a high impedance state preventing significant current flow through the associated winding of each switching device. A controller switches each of the switching devices from the high impedance state to the low impedance state in a sequence for controlling the current in the windings, which induces a phase shift between the AC voltages across the windings.

Abstract: A security electrical power interrupt apparatus prevents usage of an electrical appliance such as an electric stove, or other electrically operated device. The apparatus includes a relay controlled by a micro-processor based programmable controller. The device includes a detachable component through which data is input. Data is input to the detachable component through a key pad. A software computer program operates in the controller and causes the relay to disconnect the supply power from the device if any attempt is made to operate the appliance or device in a manner which draws electrical current exceeding a preset limit while the controller is in an interrupt mode.

Abstract: A fastener including a body, a shroud rotatably mounted on the body, and a resilient retaining ring located in opposed grooves between the shroud and the body, one end of the body extending outwardly beyond the shroud, and a frustoconical outer surface on the shroud which has its larger side proximate the end of the body which extends beyond the shroud.

Abstract: A fail-safe closed damper for installation in a system of ducts. The damper includes at least one damper blade connected to a spring-loaded shaft. A power-actuated unit is employed to disengage a coupling which interconnects the spring-loaded shaft to an operating linkage. The use of the power-actuated unit ensures that the damper will be tripped at the appropriate predetermined temperature and will not be affected by the large frictional forces imparted on the components of the damper by the biasing spring or by such external factors as dust, humidity and dirt. The damper employs a sensor having dual sensing devices and which is centrally disposed in the duct to ensure receipt of a representative sample of airflow. The damper further includes a damper blade position indicator for sensing whether the damper blade is open or closed.

Abstract: An orientation sensor especially suitable for use in an underground device is disclosed herein. This orientation sensor includes a sensor housing defining a closed internal chamber, an arrangement of electrically conductive members in a predetermined positional relationship to one another within the chamber and a flowable material contained within the housing chamber and through which electrical connections between the electrically conductive members are made such that a comparison between an electrical property, specifically voltage, of a first combination of conductive members to the corresponding electrical property of a second combination of conductive members can be used to determine a particular orientation parameter, specifically pitch or roll of the sensor.

Abstract: A novel digital servo valve system for use in controlling a displaceable actuator includes a valve body with ports, a valve spool displaceable within the valve body to regulate fluid flow through the ports, and a motor having a drive shaft which displaces the valve spool. The system is characterized by a null adjustment mechanism which makes a null rotational position of the drive shaft coincide with a null position of the valve spool, at which positions the valve spool cuts off fluid flow through the ports. The null adjustment mechanism provided in accordance with the present invention permits the null positions of the valve spool and stepper motor to be adjusted without having to disassemble the servo valve.

Abstract: An improved system for recovering and charging refrigerant of a refrigeration system. The system includes a series arrangement of two gas compressors that boost the pressure of the recovered refrigerant to a high enough level for storage in a DOT-3AA type cylinder. The recovered refrigerant is not condensed to the liquid state during recovery, nor is the cylinder chilled. The second high-pressure compressor includes a free-floating piston within a cylinder. The piston is hydraulically actuated. The system includes microprocessor control. The system is well suited for recovery of refrigerants such as R-13, R-23, R-503, and SUVA-95.

Abstract: A high-voltage switching circuit is formed of a series combination of switches, each of which is rated for use at a voltage lower than that of the power supply. The switches are connected in series with inductors, the inductors being magnetically coupled, in an anti-phase manner. A pair of capacitors, having substantially equal values of capacitance, are connected, respectively, in parallel with each series combination of a switch and inductor. The inductors and capacitors together insure that no more than one-half the total voltage of the power supply will ever appear across either switch. The series combination of switches can be used in place of a single switch, and permits the use of switches rated at low voltage to be combined to form an overall switch which works reliably at a higher voltage.

Abstract: An inverter by pass safety switch for rerouting electrical power either through or around AC variable frequency inverter drives during electrical disturbances, thus allowing a motor to continue operation. The switch works in a mechanical fashion, and comprises a contact block containing electrical contacts and cams operably connected to the contacts and mounted on a shaft that can be turned by an operator. The cams are shaped and mounted on the shaft in such a way to provide a desired switching pattern when the shaft is manually rotated.

Abstract: A power regulator system provides power to an electrical load. A power level selector generates a reference signal which indicates a desired power level for the electrical load, and a control circuit connected with a AC power source interrupts flow of the AC current for periods of time responsive to a reference system from the power selector. A filtering circuit filters the output of the control circuit and generates therefrom a second output AC circuit which is smooth relative to this interrupted AC circuit. This smooth AC output is applied to the load. A relay is provided to prevent overload conditions from forming adjacent the load in the circuit. Various types of sensors may be used as the power level indicator, such sensors including the light detector as movement detectors, and other electrical sensors.