Abstract: A sound damping wallboard and methods of forming a sound damping wallboard are disclosed. The sound damping wallboard comprises a gypsum layer with a gypsum surface having an encasing layer. The encasing layer is partially removed to expose the gypsum surface and form a gypsum surface portion and a first encasing layer portion on the gypsum layer. A sound damping layer is applied to the gypsum layer to cover at least part of the gypsum surface portion and the encasing layer portion.

Abstract: A position sensing system includes a coded tape vertically mounted in an elevator shaft and a sensor unit mounted on an elevator car to detect code indicia on the tape. The sensor unit is connected to output circuitry for converting the sensor outputs to elevator position data for transmission to an elevator controller. The tape has two parallel tracks of indicia extending along its length. The first track comprises a pseudo-random code sequence which is non-repeating along any N successive bits for the length of the tape, and the sensor unit includes a first set of sensors for detecting the indicia in the first track and producing an N-bit output representative of a coarse elevator position. The second track has spaced indicia forming a fine scale between successive coarse code positions on the first track, and a second set of sensors detects the fine code indicia and produces fine code position information at successive points between each pair of coarse code positions as the sensors traverse the tape.

Abstract: An elevator control and indicator device comprises an assembly incorporating a circuit for mounting on a panel. The control circuit is connected to a piezoelectric element for generating an elevator control pulse in response to an output signal from the element. The circuit further comprises transient voltage suppression diodes shunted across the piezoelectric element and the transistor output. The device also can be configured to provide an indication of the position of an elevator car.

Abstract: An elevator control switch and position indicator assembly for mounting on a panel comprises a piezoelectric element and a control circuit connected to the element for generating an elevator control pulse in response to an output signal from the element. A push button assembly is arranged such that when the push button is operated, a force is applied to the piezoelectric element, and the push button assembly is restrained so that it can only deflect the element a predetermined distance sufficient to produce an output signal. The assembly further comprises an integral indicator device for providing an indication to the operator that an elevator control signal has been generated. The invention also can be configured to provide an indication of the position of an elevator car.

Abstract: A system for reading or sensing the position of an elevator relative to a landing and for providing corresponding control signals to a controller for controlling the elevator movement in response to the sensed position comprises a tape veritically mounted in an elevator shaft and having reflective vanes positioned on it to indicate position relative to a landing. Sensors are mounted on the elevator car and produce predetermined output signals in response to detection of vanes, and suitable control circuitry responds to predetermined combinations of the sensor output signals to produce suitable output control signals to a controller which controls the car's speed, direction and positioning. The system is installed by first vertically mounting a suitable tape in an elevator shaft so that it runs through a sensor unit mounted on an elevator cab, and positioning vanes on the tape at predetermined positions relative to each floor.

Abstract: An audible warning device is disclosed that is for use with internal combustion engines to monitor engine temperature and oil pressure and produce an audible warning signal if an over-temperature or oil pressure loss situation develops. An integrated circuit voltage comparator compares the output of a variable resistance temperature sensor against a reference voltage that is generated by a resistor network. The comparator drives an audible signal transducer to warn an operator of an over-temperature condition. Additionally, an input to the comparator from an oil pressure switch causes an audible warning to be produced if a loss of oil pressure is encountered. Self-test features are included to produce momentary audible signals each time the engine is started to indicate proper circuit functioning.

Abstract: An isothermal process solar collector panel is disclosed. The panel includes a collector plate for absorbing radiant heat; and a plurality of isothermal process heat pipes in an array over a surface of the collector plate. Each heat pipe is closed at both ends and contains thermodynamic working fluid for transferring heat energy from the collector plate to a second fluid flowing through a manifold pipe for conducting the heat energy from the collector panel. The manifold pipe is coupled to the heat pipes. One end of each heat pipe is coupled to the collector plate and has an evaporator section wherein heat energy is transferred from the collector plate to the thermodynamic working fluid; and the other end of each heat pipe is positioned within the manifold pipe and has a condenser section wherein heat energy is transferred from the thermodynamic working fluid to the second fluid flowing through the manifold pipe.

Abstract: The inherent phase ambiguity that results from the measurement of the phase difference between a reference signal and a data signal having a zero phase relationship is eliminated by adding 360.degree. to phase differences between 0.degree. and 180.degree.. Phase differences between 180.degree. and 360.degree. are measured in the conventional manner. Both the reference signal and the data signal are divided in frequency and the phase difference between the divided signals are compared. The data signal is inhibited for only 180.degree. of the original reference signal to prevent an initial comparing of phase differences between the data signal and the reference signals to establish the proper polarity relationship between the half rate data signal and the half rate reference signal.