Abstract: The present invention provides a simple apparatus for modifying at will the trajectory of heads in a rotating head magnetic recorder (for example, when the playback speed is changed) without introducing any active elements in the moving parts. Fixed electromagnets, controlled by a position sensor, control pendulum movements of the heads oscillating under centrifugal force due to their rotation.

Abstract: A flow meter comprises electrodes (16, 18), induction windings (12, 14), a winding driver circuit (20), and a processor circuit (22). The winding excitation current is a combination of a current of period T.sub.1 and a current of period T.sub.2, where T.sub.2 >T.sub.1. The processor circuit (22) processes the voltage signal sent by the electrodes and generates intermediate measurement signals of periods T.sub.1 and T.sub.2. These signals are then used to generate a correction signal for removing the relaxation effect from the measurement signal S.

Abstract: Apparatus for recording and reading information on a magnetic tape, comprising heads rotating in the median plane of a drum (38) against which the tape can pass over a helical path (11). Means are provided for modifying the pitch of the helical path (11) of the tape, such as two movable rollers (55, 56) disposed respectively downstream and upstream of the drum (38), separated by a fixed difference in height and adapted to move in such a manner as to vary the length of the portion of tape connecting them without varying said difference in height.

Abstract: A Hall device is formed from a generally rectangular body of material exhibiting the Hall effect, with two excitation electrodes disposed along opposite edges of the device. Two Hall output voltage electrodes are disposed along one of the remaining edges of the main body and at least one additional output electrode is disposed on the edge of the main body opposite the first pair of electrodes. At least two of the output electrodes are offset from a centerline drawn through the electrical midpoint of the main body. By deliberately offsetting the Hall voltage output electrodes from the centerline the first and second order voltage offsets due to inhomogeneities of the Hall material and mask misalignment are eliminated or easily compensated.

Abstract: A solid state electricity demand recorder (10) is controlled by a programmable microprocessor (38) to obtain energy demand survey and billing data. The accumulated count of pulses during a record interval is compared with an encoded register reading obtained from an electricity meter (30) at the end of the reord. If there is acceptable correlation between the accumulated count and encoded meter reading, the interval pulse counts associated with that record are deemed verified. Power for the recorder (10) is obtained from the power line, except during power outages in which case a battery (28) provides back-up power. Error conditions such as power outages, meter failure, and low battery condition are automatically detected and communicated to the central computer for remedial action by the electrical utility.

Abstract: A solid state electricity demand recorder (10) is controlled by a programmable microprocessor (38) to obtain energy demand survey and billing data. The accumulated count of pulses during a record interval is compared with an encoded register reading obtained from an electricity meter (30) at the end of the record. If there is acceptable correlation between the accumulated count and encoded meter reading, the interval pulse counts associated with that record are deemed verified. The recorder then downloads the recorded demand data to a central computer at a preselected time over a communications line. The recorder is receptive to communications and commands from the central computer at times other than the normal preprogrammed data downloading time by detecting a particular number of rings.

Abstract: A solid state electricity demand recorder (10) is controlled by a programmable microprocessor (38) to obtain energy demand survey and billing data. The accumulated count of pulses during a record interval is compared with an encoded register reading obtained from an electricity meter (30) at the end of the record. If there is acceptable correlation between the accumulated count and encoded meter reading, the interval pulse counts associated with that record are deemed verified. The recorder is programmably configurable for operation over a wide range of customer demand by scaling the KYZ pulse input frequency.

Abstract: A charge balance voltage-to-frequency converter utilizes CMOS circuitry to provide a digital pulse output proportional to an analog input signal. The converter approaches a desired charge balance by cycling between a charging and a discharging state. A clock signal provided by a stable oscillator is applied to a clock input of a CMOS D-type flip-flop. The analog input signal effectively is fed to a non-inverting input of an integrating amplifier. The output of the integrating amplifier is fed to the D input of the flip-flop, which input has a threshold level. The Q output of the flip-flop is connected via a voltage divider to an inverting input of the integrating amplifier. This configuration eliminates the need for a dual polarity power supply. When the output of the integrating amplifier rises above the threshold level of the D input, on the next rising edge of the clock signal, the flip-flop sends feedback pulses to the inverting input, thus beginning the discharge state.

Abstract: In a solid state electricity meter, a display consisting of a number of juxtaposed display elements provides, in a vector form, an indication of the direction and range of power flow in the line being measured. Circuitry for driving the vector display comprises a first memory storing a plurality of power measurement references and a second memory storing corresponding vector symbols. A microprocessor compares each power measurement with the reference stored in the first memory to determine the range of power measurement and, in response, reads the corresponding vector symbol from the second memory to drive the display.

Abstract: A solid state electricity demand recorder (10) is controlled by a programmable microprocessor (38) to obtain energy demand survey and billing data. The accumulated count of pulses during a record interval is compared with an encoded register reading obtained from an electricity meter (30) at the end of the record. If there is acceptable correlation between the accumulated count and encoded meter reading, the interval pulse counts associated with that record are deemed verified. Power for the recorder (10) is obtained from the power line, except during power outages in which case a battery (28) provides back-up power. The time of day and date of detection of a low battery condition is stored and used to assess data reliability.

Abstract: The invention provides a DC-FM phase locked loop for use in transmitters for measuring and control purposes, wherein the modulation signal controls, via an A/D converter, the output frequency of a frequency synthesizer, this output frequency being used as the reference for the phase comparator. This permits modulation with extremely low frequencies or DC without the necessity to interrupt the loop.

Abstract: The present apparatus concerns round monitoring and includes a portable recording device together with a plurality of keys for indicating different locations through which a watchman is to pass. In order to simplify the drive mechanism of the apparatus, the apparatus comprises a clock movement (20) having an hours shaft on which a disk (34) is mounted having time data print elements (36) disposed around its rear face. A strip of paper (50) is displaced between said print elements (34) and a print hammer (52).

Abstract: A card reader for electronic memory cards of the type which include a integrated circuit and integral electrical contact pads. The card reader includes a slot for introduction of the card. Within the slot are a series of contact elements for supplying power and information signals to the contact pads on the memory card. A card position detector, e.g. a microswitch, detects when the card is in the correct position, i.e. when the contact elements are contacting the electric contact pads of the memory card. When the card is so positioned, electric power and information signals are applied to the contact elements and then to the integrated circuit of the memory card via the electric contact pads.

Abstract: A method of initializing the position of an optical shaft encoder without having to precisely index the encoder with respect to its shaft. The optical encoder includes an optical shutter mounted for rotation with the shaft and light emitters and light detectors associated with the optical shutter for respectively illuminating and detecting a predetermined pattern of code markings formed on the optical shutter. An electrical circuit, such as a suitably programmed microprocessor, is responsive to the status of the light emitters and light detectors for determining the angular position of the optical shutter and shaft relative to the light emitters and detectors from the detected predetermined pattern. The optical shutter is mounted to the shaft in some arbitrary position and the code pattern associated with this position is detected by the electrical circuit.

Abstract: An electrical time-switch has two relays on a circuit board with electrical connector blades extending from it. A backplate carrying cable connectors is provided with slots such that it can be fitted over the blades, making electrical connection between the cable connectors and the circuit board, with either face exposed. Thus the same backplate can be used for both wall-mounting and panel-mounting, while maintaining ease of access to the cable connectors for cable attachment. An optional unit with a second pair of relays can be fitted on the circuit board and has additional blades for connection to the extra relays.

Abstract: A measuring diaphragm (1) separates in a pressure-tight manner two half chambers (9, 10) suitable for being respectively subjected to two pressures to be compared. In a central zone of the diaphragm (1) there are two magnetic cores (118, 127) which are disposed on opposite sides of the diaphragm in respective ones of the half chambers and which are displaced with the diaphragm when the faces of the diaphragm are subjected to different pressures. The cores are movable inside respective simple inductors (132, 133 ), thereby varying their impedances. By measuring this impedance variation it is possible to determine the position of the cores in the associated inductors, and consequently to establish the difference between the pressures being applied to respective faces of the measuring diaphragm (1). The above arrangement provides for automatic zero correction in an inductive differential pressure sensor.

Abstract: In order to reduce the measurement time of a device for measuring fluid temperature, in particular of water in the primary circuit of a nuclear power station, the device comprises a resistance probe (50) sensitive to the temperature of a stem (23) which is removably slid into a socket (1) itself secured in the pipe in which flows the fluid (10) whose temperature is to be measured. The stem ends with a surface in the form of a convex segment of a sphere (39) arranged to be urged by a resilient member onto a dish (42) force-fitted in the bottom of the socket.

Abstract: It is proposed to store spent nuclear fuel elements in welded-shut steel containers, which are filled with argon at about 2 atmospheres pressure. It is desirable to be able periodically to check the containers for leaks. The invention proposes to do this by providing apparatus for sensing the pressure within the container from outside the container. To achieve this, a pressure responsive bellows is mounted inside the container, such that changes in the container pressure move a metal plate attached to the bellows towards or away from a portion of the inside wall of the container. Then, if the container starts to develop a leak, the pressure will begin to drop, and the gap between the metal plate and the wall will change. This gap can be sensed from outside the container, by an ultrasonic pulse echo technique. Preferably, the bellows and plate are mounted within the head of the combined valve and lifting pintle by which the container is sealed.

Abstract: Tampering with an optically encoded meter display register or metering mechanism can be readily detected by comparing the quantity shown by the meter display with the encoded values of the optical encoders. A discrepancy is indicative of tampering with the register display. Any tampering with the optical encoders or the metering mechanism can be detected by comparing the present position of the encoders with that of a previous position and generating a signal indicative of tampering when these positions have a predetermined relationship to each other.

Abstract: A thermal link provides a thermal path between a heat source and a heat sink which compensates for irregularities on the surface of the heat source and/or heat sink and/or nonuniformity in the spacing therebetween. One embodiment utilizes a spring metal device having a free arm which allows the link to align itself under low pressure so that it is in intimate contact with both the heat source and heat sink. Another embodiment utilizes an elastomeric material filled with thermally conducting particles to form a mat that has a plurality of raised sections having air spaces between each of the sections. The raised areas deform under low pressure by expanding laterally into the air spaces to conform to the space between the heat source and the heat sink.