Abstract: A hydraulic torque impulse generator uses a dual piston arrangement to provide impacts to a rotative anvil and automatic shut-off and control apparatus for limiting the pressure without reversing the direction of the driving clutch cage, a pressure venting arrangement permitting one impact per revolution.

Abstract: A reversible powered impact wrench is provided wherein improvements are incorporated in the detenting of the reverse direction valve, venting of excessive air pressure within the impact wrench motor housing which may use light weight material due to improved clutch and camming means and wherein an improved one piece anvil-timing shaft is designed to be supported by the impact wrench hammer and rotor.

Abstract: A hand held pneumatic tool is provided for driving fasteners in which the cam shape and arrangement between the driving and driven cams provides a "dwell" time for preventing further impacts after the desired torque has been reached and a latch arrangement provided to prevent undesired shut-off in the reverse direction of operation. Means are provided to assure restart after shut-off, and a ball spline between the driven cam and spindle is used to increase accuracy.

Abstract: A gasket assembly including a base having a central opening and a circular slot having an undercut portion extending around the central opening, a circular gasket positioned in the circular slot and having a tapered side located proximate the undercut portion, and cementitious sealant material abutting the tapered side of the gasket and in the undercut portion for retaining the gasket in the slot. The gasket assembly is especially useful for the seal for the pressure relief valve of an electrical power transformer.

Abstract: An electronic relay control circuit is provided for liquid cooled electric power transformers. The control circuit senses the rate of change of internal tank pressure and operates its relays in response to a sudden pressure increase. Relay control connections are provided for operating transformer trip and annunciator circuits. The relay response is field adjustable.

Abstract: An improved ratchet wrench tool ratcheting mechanism is provided wherein springs encased in the shank spindle have balls at each end of the springs to abut fixed washer surfaces so that tool operation and life is improved by increasing the frictional force and reducing the spring stress, unbalanced load, and housing yoke wear experienced by prior art mechanisms.

Abstract: A method and system is provided for electronically simulating, indicating and controlling the temperature of liquid cooled multi-phase electric power transformers. The temperatures of transformer windings are electronically computed from the actual top oil temperature and the computed incremental additional temperatures resulting from the transformer winding currents to determine the hottest spot temperature. The signals representative of the winding current for each phase of the multi-phase transformer are time processed to simulate the rate of rise of winding temperature resulting from those currents. A square-law function is generated to make a winding bias parameter for each winding. The signals representative of the actual and incremental additional temperature are added for each transformer phase and the largest signal, representative of the hottest winding is used to indicate and control the transformer temperature.

Abstract: A method and system for indicating and controlling the temperature of liquid cooled multi-phase power transformers. The winding temperatures of a transformer are electronically computed from the actual top oil temperature and the incremental additional temperatures resulting from the highest transformer load current to determine the hottest spot temperature. One curve from a family of curves representing the incremental temperature for various transformers may be selected or programmed by adjustments made which simulate the incremental additional temperature which results from transformer winding current. In this way the input current range, winding bias setpoint, winding bias curve, and time-constant can be chosen independently so that any electric power transformer may be simulated.

Abstract: A method and system for controlling the temperature of liquid cooled power transformers. The winding temperature of a transformer winding is electronically computed from the actual top oil temperature and the incremental additional temperature resulting from transformer load current. One curve from a family of curves representing the incremental temperature for various transformers may be selected or calibrated by adjustments made which simulate the incremental additional temperature which results from transformer winding current. The total temperature value resulting from the addition of both the top oil temperature and the incremental temperature are used to control indicators, cooling fans, circuit trips and retain an indication of the highest temperature occuring during the time period of interest.

Abstract: A method and apparatus is provided for computing the life expectancy of electrical power transformers by computing the used life of a transformer at a rate determined by the Arrhenius function of the temperature of the transformer device being monitored.

Abstract: A rotatable one-piece lens assembly that may be rotated relative to the instrument housing comprising a lens boss, integral with the lens, moving with the rotated lens to move the pointer to engage and test the switches. After the switch test the lens may then be rotated back to its normal position. In this manner the switches are tested without removing the lens from the instrument housing.

Abstract: A vibratory impact hammer including a hammer body assemblage suspended by rubber mounts for reciprocal axial movement in a support frame, the rubber mounts providing guiding and damping action of the assemblage in either director of axial movement without extraneous friction forces acting thereupon, and a pair of synchronously driven eccentric weights which are arranged to provide vibratory movement of the assemblage.