Abstract: A portable gas pressure monitor includes a pressure sensor which may be coupled to a pipeline tap downstream of a work area, and first and second comparator circuits receiving the signal from the pressure sensor and comparing the pressure signal with a low pressure set point and a high pressure set point. The two set points define a safe range for the pressure of the gas being monitored. If the sensed gas pressure falls below the low set point one audible signal is generated, and if the sensed pressure exceeds the high set point, a distinctly different audible signal is generated, thus immediately and unequivocally alerting operating personnel of the nature of any alarm. The pressure is also displayed for the operator.

Abstract: A carriage having rotary cutter wheels is mounting for reciprocation on a frame adapted to be rigidly secured to a pipe casing which is desired to be split along a line parallel to its axis. A hydraulic motor is mounted to the frame at one end of the carriage. A rotary crank driven by the motor is coupled to an arm which is also coupled to drive the carriage in a reciprocating motion. An adjustable hydraulic valve controls the speed of the motor, and thus the speed of the cutter. An adjustable stabilizer is mounted to the frame to stabilize the cutter by bracing against the carrier pipe within the casing.

Abstract: A remote logger unit monitors various operating parameters of a distribution line, or transmission system, such as pressure, temperature and flow such as for natural gas, water or oil, and alerts a central controller via an RF link when predetermined operating limits as determined by the logger unit are exceeded. A plurality of such remote logger units may be employed along the length of the distribution line for monitoring the complete system, with the reports of more distant logger units routed to the central controller via closer logger units. Each logger unit is passive in operation, autonomous and entirely independent of the central controller, and also provides routine operation data to the central controller when prompted, or at designated time intervals. The reported data includes the identity of the logger unit, the nature of the data or alert, and the time and date of the report.

Abstract: Apparatus for covering an opening in a pipe and sealing a gas or fluid leak includes first and second pipe engaging blocks coupled to a frame. With the second block fixedly mounted to the frame and the first block movable along the frame by means of a hydraulic cylinder coupled thereto, the first block is positioned over and seals the leak under the force of hydraulic pressure. The frame includes first and second mounting arrangements for attaching an articulated boom such as on a backhoe to either an end of the frame (for positioning the apparatus in a generally upright orientation) or to an intermediate portion of the frame (for positioning the apparatus in an inclined orientation). The position of the second block along the length of the frame is adjustable depending upon the diameter of the pipe. A guide rod couples the movable first block to the frame to ensure linear displacement of the first block and proper alignment between the first and second blocks during engagement of the pipe.

Abstract: Apparatus for covering an opening in a pipe and sealing a gas or fluid leak includes first and second pipe engaging blocks coupled to a frame. With the second block fixedly mounted to the frame and the first block movable along the frame by means of a hydraulic cylinder coupled thereto, the first block is positioned over and seals the leak under the force of hydraulic pressure. The frame includes first and second mounting arrangements for attaching an articulated boom such as on a backhoe to either an end of the frame (for positioning the apparatus in a generally upright orientation) or to an intermediate portion of the frame (for positioning the apparatus in an inclined orientation). The position of the second block along the length of the frame is adjustable depending upon the diameter of the pipe. A guide rod couples the movable first block to the frame to ensure linear displacement of the first block and proper alignment between the first and second blocks during engagement of the pipe.

Abstract: A system for selectively obtaining information from a plurality of remotely located data indicating devices includes an interrogate source and a plurality of transponders each associated with a different one of the data indicating devices. The interrogate source transmits an interrogate signal for effecting the readout of a selected indicating device, the interrogate signal being a high frequency carrier amplitude modulated with a pair of low frequency signals to represent an eight bit sync code word, a four bit command word and a twenty-eight bit identification code word for addressing a selected transponder.

Abstract: An optical encoder for indicating revolutions of a shaft includes two phototransistors positioned to be energized concurrently by light from a light source, a barrier rotated by the shaft to shade the photosensors from the light source during a portion of each revolution, and a signal processing circuit which responds to outputs of the photosensors when both are illuminated to provide an unambiguous indication at the end of each revolution of the shaft. The signal processing circuit includes a latch circuit which is set in response to one photosensor, providing an output while the other photosensor is providing its output. The latch circuit is reset when the outputs from both photosensors terminate.

Abstract: A solid state oscillator circuit for operation at very high frequencies includes a field effect transistor having an input network connected between its gate and source electrodes and an output network connected between its drain and source electrodes, the input and output networks each including three discrete capacitors connected in a "pi" configuration, the input and output networks being connected in series with one another, and an inductor being connected in parallel with the series connected networks, the equivalent circuit impedance of the networks in series and the inductance determining the operating frequency of the oscillator circuit, and the relative ratio of impedance of the networks determining the amount of oscillator feedback.

Abstract: A top-loaded low profile antenna for data transponders includes an antenna pin mounted vertically, affording vertical polarization for the antenna, an aluminum plate mounted in a horizontal plane and connected to an upper end of the pin, providing top-loading of the antenna, the plate being supported by a lucite frame mounted on an upper surface of the data transponder and which also dielectrically loads the antenna feed region. The load plate and lucite frame enclose the antenna pin so that the antenna is less susceptible to vandalism, and the top-loading results in a reduction in the height of the antenna structure improving the aesthetics of the antenna and data transponder installation.

Abstract: A method for storing electric power and later utilizing the stored power is described which includes the steps of converting the electric power to chemical energy of molecular hydrogen, reacting the hydrogen with a source of carbon to produce a hydrocarbon compound such as methane or methanol, storing the hydrocarbon compound, and then supplying the hydrocarbon compound as fuel to a generator which operates to generate electric power. In one embodiment of the invention the hydrocarbon fuel is used to heat stored compressed air which is in turn used to drive a turbogenerator.

Abstract: The instrument uses a semiconductor gas sensor element energized with a regulated voltage source and placed in the atmosphere to be tested to generate a signal representative of the concentration of natural gas in the air. A meter displays the signal to determine whether the area is hazardous, and a variable repetition rate blocking oscillator feeding a speaker is responsive to the signal for generating an audible tick rate useful in locating a leak. The instrument is light-weight, portable, easy to use and intended to comply with industry standards as an intrinsically safe instrument.

Abstract: A frequency/space diversity data transmission system includes a transmitter for transmitting two or more distinct RF signals having the same modulation from different antennas separated a wavelength or more, the frequency spacing of the carrier signals being at least ten times greater than the frequency of the modulating signal, and a broad band receiver including a video diode detector and a frequency demodulator which recovers the modulating frequency from the carrier.

Abstract: A system for providing remote readout of a plurality of groups of data indicating devices including a control unit for each group of data indicating devices for receiving interrogate data signals transmitted over a communication line or RF signal link from an interrogate unit at a central location to the locations of the control units, and for transmitting the interrogate data to transponders associated with the indicating devices over existing electrical power lines to which the control unit and transponders are connected via existing electrical outlets. The transponders are responsive to the interrogate data to generate reply data representing the reading of an associated indicating device for transmission over the electrical power line to the control unit which effects the transmission of the reply data to the central location.

Abstract: An improved remote meter reading system is disclosed comprising apparatus for transmitting UHF AM interrogating signals from an interrogating mobile or central station to a remote transponder station, and apparatus for retransmitting UHF FM data signals from the energized transponder to the mobile or central interrogating station. The interrogating station further includes apparatus for validating that the UHF FM data signals received are in fact the UHF FM data signals actually sent by the remote transponder selected by the interrogating or central station.

Abstract: A data transmission system for obtaining information from a plurality of data sources includes an interrogate source for transmitting RF interrogate signals to the locations of the data sources and a transponder associated with each data source for receiving the interrogate signals and for generating RF reply signals representing the information. The transponder includes a transmitter having a voltage controlled oscillator responsive to data signals at first and second levels to generate sinusoidal output signals at first and second frequencies, respectively, a wave shaping circuit which converts the output signals to sawtooth wave signals at the corresponding frequencies and an FM oscillator for providing a carrier signal which is modulated by the sawtooth signals to produce a broad spectrum of sideband signals of approximately equal amplitude.