Abstract: A fluid flow speed measuring apparatus comprising a first pipe having an opening exposed into a fluid to be measured, a direction of the opening having an angle larger than a critical negative pressure angle, a second pipe having an opening exposed into the fluid to be measured, a direction of the opening of the second pipe having an angle larger than the critical negative pressure angle and at least one of conditions such as a diameter, a direction, and the number of the openings for determining a magnitude of the negative pressure being different from that of the opening of the first pipe, negative pressure difference detector for detecting a difference between negative pressures acting on the openings of the first and second pipes, and device for calculating a flow speed of the fluid to be measured on the basis of an output from the negative pressure difference detector.

Abstract: A membrane keyboard blockout apparatus for a keyboard having an array of a plurality of flexible key members in respective ones of a plurality of apertures arranged in a grid forming the keyboard includes a cover plate dimensioned to span a flexible key member and to provide a tight fit within an aperture defining a key member. The cover plate has a thickness providing a substantially inflexible configuration in response to normal operator manipulation and a plurality of corner support pedestals contacting respective corners of the flexible key member when the cover plate is inserted in a key member aperture. Thus, the pedestals provide a support between the cover plate and the flexible key member at the edges of the key member to preclude, in combination with the inflexible structural characteristic of the cover, an actuation of the flexible key member under the cover.

Abstract: A color sensor has a layered body obtained by stacking a first photoelectric sensor which is constituted by an amorphous semiconductor having a "PIN" structure and a spectral sensitivity which has a peak with respect to blue light and a second photoelectric sensor which is constituted by an amorphous semiconductor having a "PIN" structure and a spectral sensitivity which has a peak with respect to red light, so that a p-n junction is formed therebetween, and a pair of electrodes with each of the electrodes being provided at a respective end of the body, at least one of the pair of electrodes being transparent. A color measuring apparatus uses the color sensor with a bias voltage supply for supplying three different bias voltages between the sensor and the pair of electrodes, a photo-current detector for detecting photo-currents for each bias voltage and a color discriminator for discriminating incident light color on the basis of the detected photo-currents.

Abstract: A method for providing a power management for a DC solenoid actuator includes the steps of initially supplying a first number of DC current pulses to the actuator and after a first time interval reducing the number of pulses applied to the solenoid in direct proportion to an output voltage of a source of the DC power. The method further includes the step of changing the duration of the first time period in direct proportion to the output voltage of the source of the DC power.

Abstract: A method for operating a transmitting/receiving circuit for ultrasonic signals includes the steps of producing a carrier frequency by a voltage-controlled oscillator having an output frequency controlled in accordance with a temperature dependency of an inherent frequency of the transducer, modulating the carrier frequency, applying the modulated carrier frequency in a transmitting mode to energize an ultrasonic transducer to produce ultrasonic transmission signals, switching from the transmitting mode to a receiving mode, applying output signals from the transducer representative of received ultrasonic signals to a phase-locked-loop circuit using the voltage-controlled oscillator whereby the phase-lock-loop circuit is automatically matched to a frequency of the received signals.

Abstract: A transmitter for repeatedly transmitting a measured value in the form of a digital signal through a two-wire transmission line, includes a receiving unit for receiving a digital command signal from a communicator through the two-wire transmission line, and a processor for sending out a response signal in response to the command signal upon reception thereof. The measured value is sent using a newest measured value after repetitive transmission of the measured value is interrupted. The measured value is transmitted from the transmitter by a change in current supplied to the two-wire transmission line, and reception of the command signal is performed by a change in interline voltage of the two-wire transmission line.

Abstract: A cold junction compensation apparatus utilizes a block of thermally conductive material, such as copper, having a mounting flange extending radially outwardly which is attached to a terminal strip by a machine screw to maintain the screw temperature substantially at the temperature of the block of thermally conductive material. The temperature of the block is sensed by means of a temperature sensor inserted into a hole extending through the block. The sensor is supported on a printed circuit board and is inserted through the hole in the block during assembly of an apparatus using the cold junction temperature compensation. The block is covered by an exterior insulating sleeve to prevent electrical shorts and rapid temperature changes in the block.

Abstract: A pressure activated reserve battery, capable of being activated by increasing external or environmental seawater pressure as the device is lowered or sinks to depth, without benefit of an external pressure hull. Pressure compensation, balancing of external seawater pressure and internal electrolyte pressures continually after activation of the device precludes the use of a pressure hull. A pressure activated battery, made up of reserve cells, for selectively providing stored reserve electrolyte into cell electrode environments upon application of a specified activation pressure. Each cylindrical reserve cell housing includes an electrolyte reservoir and a cell electrode assembly. A first barrier having a pressure rupturable disc is arranged to provide a fluid-tight separation between the electrode assembly and the electrolyte reservoir.

Abstract: A reserve activated electrochemical cell uses a frangible glass ampule for storing an electrolyte. The ampule is located within a first cylindrical cup-shaped metal housing containing a pair of cell electrodes. One of the electrodes is formed by an electrically conductive ring electrically isolated from the wall of the housing while the other electrode is constituted by an electrically active coating on an inner surface of the wall of the housing. The first cylindrical housing is arranged to form a contiguous extension of a second cylindrical metal housing and is attached by an electrically conductive weld bead located along a peripheral edge of an open end of the cup to the second housing to form a fluid-tight seal therewith while facilitating an electrical connection to the first one of the electrodes. An electrical connection to the other one of the electrodes is provided by a wire extending through a fluid-tight seal in a wall of the second housing and connected to the other electrode.

Abstract: A receiver for receiving a reception signal defining a measured value is connected to a two-wire transmission line used for transmitting a digital command signal from a communicator, a digital measured value signal from a transmitter, and a response signal responding to the command signal. The receiver includes a timer for discriminating that a nonsignalling state of the two-wire transmission line has continued for a predetermined period, and a CPU for validating a specific period of a reception signal received after the discrimination operation of the timer.

Abstract: A refrigeration system control for minimizing cycling losses of a refrigeration system having an indoor coil, an indoor coil fan, an outdoor coil, an outdoor coil fan, a refrigerant line between one end of the indoor coil and one end of the outdoor coil, a compressor apparatus and a reversing valve connecting the compressor apparatus between the other end of the indoor coil and the other end of the outdoor coil includes the steps of operating the reversing valve to a state opposite to the one representative of the operating condition of the refrigeration system for a predetermined period of time starting prior to an energization of the compressor apparatus and ending after the energization of the compressor apparatus, restoring the reversing valve to a state needed for the operating condition of the refrigeration system at the end of the period of time while continuing the energization of the compressor apparatus.

Abstract: A slow opening and fast closing gas valve includes a valve seat and a valve closure member arranged to respond to a gas pressure to seal aganst the valve seat to close the valve to an input gas flow therethrough. In order to open the valve, the gas exerting the gas pressure for sealing the valve closure member against the valve seat is allowed to bleed-off through a fixed restriction while the input gas is allowed to urge the valve closure member away from the valve seat to provide a slow opening of the input gas flow path through the valve. In order to close the input gas path through the valve, the input gas pressure is applied to the valve closure member to assist a closure spring in urging the valve closure member against the valve seat to produce a fast closure of the valve. A second valve is arranged to selectively control the flow path of the gas being bled off from the valve closure member to provide an unrestricted flow path or a restricted flow path through the fixed restriction.

Abstract: A method of producing a fluid-tight seal between a thin, flexible member and a member support including the steps of providing a braze material receiving recess on an external surface of the member support having a depth to accommodate excess braze material during the brazing of the member to the support, providing an upwardly extending ridge on the external surface spaced from the recess and having a height above the external surface equal to the thickness of the braze material used to braze the member to the support, positioning the member to extend across the recess, the surface and the free end of the ridge and brazing the member to the surface while maintaining the contact between the braze material and the member and between the free end of the ridge and the member.

Abstract: A gas control apparatus with a pressure regulator selectively controls the setpoint of the regulator by an electrical current between a minimum and a maximum value of the gas outlet pressure. A diaphragm of the regulator is exposed to the pressure to be controlled and carries a closure member of a bleed valve. A control spring for determining the setpoint of the gas pressure acts between the diaphragm and an adjustable abutment. A solenoid actuator acts between a valve rod of a switch-on valve located between an inlet of the apparatus and the regulator and the abutment. A reset spring for the armature of the actuator acts between a stationary abutment and the armature to engage the armature after the armature has opened the switch-on valve. Thus, the solenoid actuator responds to an electrical current to control the operation of the switch-on valve to provide an inlet pressure for the regulator.

Abstract: A differential pressure signal generator uses a pressure sensor arranged to sense differential pressure between a pair of right and left pressure measuring chambers in right and left portions of a signal generator body to which high and low pressure-side measured pressures are applied through respective barrier diaphragms and a center diaphragm arranged to define right and left pressure measuring chambers with the center diaphragm providing a pressure coupling to a fill fluid contacting the pressure sensor and being made of a material having a larger thermal expansion coefficient than the right and left portions of the generator body to provide an ambient temperature compensation by absorbing temperature induced volume changes in the full fluid. The temperature compensation is also applicable to an absolute pressure signal generator using a diaphragm to transmit a measured pressure to a sensor located within a body of the signal generator.

Abstract: An apparatus for detecting the distance of an object from a signal transmitter during radiation of a transmitter signal uses a first capacitor which is initially short-circuited by means of a first switch and subsequently is charged from a constant current source following an opening of the switch. Upon a reception of an echo signal, the charge of the first capacitor is transferred to a second capacitor by closing a second switch at the time of the echo signal reception. The charge on the second capacitor, which is proportional to the elapsed time between transmitted and received signals, is delivered to an output via a low pass filter with the output signal representing a distance measuring signal.

Abstract: A composite material and metal canister has a cylindrical corrosion resistant metal shell and a composite material bulkhead within the shell which provides corrosion resistance and minimal weight coupled with the ability to withstand high internal pressures and bending stresses. The metal shell and the composite bulkhead are joined by a circumferential compression exerted on the shell by an external ring of shape memory material to produce a fluid-tight seal therebetween the shell and an adjacent bulkhead. A pair of composite material bulkheads and a pair of shape memory material rings can be used to seal both ends of the shell by locating an inner bulkhead and an external ring at respective ends of the shell.

Abstract: A two wire line voltage thermostat has first and second terminals for receiving line voltage power and for connection to a load, a transformer having a current primary winding, a voltage primary winding and a secondary winding, a primary controller connecting the current and voltage primary windings to the terminals, the controller having at least first and second states, the controller in the first state energizing both the current and voltage primary windings and in the second state energizing only the current primary winding, and a temperature responsive circuit connected to the secondary winding for controlling the controller between the first and second states in accordance with sensed temperature such that the load can be energized when the controller is in one of the states and can be deenergized when the controller is in the other of the states.

Abstract: A method for detecting very small concentrations of gases in gas mixtures passed as a gas stream through a measuring cell having a chamber through which the gas stream flows through, a drift zone provided between an inlet and an outlet of the chamber, a gas stream ionizing radiation source located at the inlet of the drift zone, a collector electrode located at the outlet of the drift zone, a grid consisting of two groups of parallel wires located in the drift zone current adjacent grid wires are supplied with different electrical voltages and whereat an AC voltage of adjustable frequency is fed to the two groups of grid wires, and a measuring apparatus for detecting the collector current, including the steps of inducing the movement of the ions through the drift zone by means of a ventilator which generates a controlled gas flow to the collector electrode, periodically changing the frequency of the AC voltage applied to the groups of grid wires either continuously or stepwise, simultaneously measuring the co

Abstract: For the evaluation of a film independent of its predetermined recording velocity, a film storage drum is provided on which a film take-up reel is mounted. The film storage drum and the film take-up reel are capable of rotating with respect to each other in both directions. The film is fed via the storage drum to the film take-up reel, whereat a film evaluating device is mounted on the storage drum with the film passing the evaluating device on its way from the storage drum to the film take-up reel.