Abstract: A clock signal extraction circuit for extracting a clock signal from a reproduced self-clocking digital recording while masking unwanted data transitions from the extracted clock signal. A plurality of input single-shots are selectively operated to produce control signals having respective durations for controlling the gating of a reproduced self-clocking input signal. The gating of the input signal allows only the clock signal transitions in the input signal to be applied to a clock signal output. The single-shots are selected by a comparator circuit which sequentially compares the time of occurrence of the extracted clock signal to each of a plurality of nominal occurrence times equal in number to the number of input single-shots to be controlled thereby.

Abstract: Variable incrementation of an analog output signal is achieved by using a variable frequency clock generator for providing input signals to be counted by a presettable counter. The counter is preset by a digital word from a control processor which may include a digital computer. An output signal from the counter is applied to a digital-to-analog converter to produce a process control analog signal. The output signal of the variable frequency clock generator is obtained by a sequential selection of a plurality of differing fixed frequency signals from a frequency divider arranged to generate a plurality of lower frequency signals from a fixed frequency clock signal source. A second counter is driven by an output of the frequency divider to further subdivide the clock source signal.

Abstract: A bar graph device has a column of 200 cathodes connected in three sets which are energized in sequence to give a visible gas discharge which travels up the column from a reset cathode. The cathode drive is from a clock which also drives a sawtooth which is compared with the input signal. When equality occurs, the anode is de-energized to extinguish the discharge. Cathode drive continues until all cathodes in the column have been energized. Divide-by-200 circuitry ensures proper resetting. Scale markers are provided in the display itself by splitting the divide-by-200 circuit as shown, and using the pulses from the divide-by-5 section to fire a one-shot and a disable gate for, say, three clock pulses. This effectively freezes the system after every five pulses passing through the gate, resulting in the display in the device dwelling on every fifth cathode; these cathodes, therefore, appearing brighter than the rest.

Abstract: A pressure to current transmitter has an internal fill fluid chamber separated from a process fluid by a diaphragm and backup plate. A fluid-tight seal is achieved between the backup plate and the wall of the fluid chamber by a continuous weld bead while the wall of the chamber is arranged on a flexible cantilever to accommodate differential thermal expansion between the backup plate and the chamber wall.

Abstract: A calibration device having a thermally insulated storage receptacle for a liquid to be analyzed. The liquid is converted to a vapor form by passing a carrier gas through the liquid to be analyzed whereby the carrier gas is saturated with the liquid. The partial pressure of the liquid vapor in the gas is the function of the temperature of the liquid and the pressure of the saturated carrier gas. The saturated carrier gas is applied to the sample inlet of a vapor phase analyzer by a sample transport line that is maintained above the dew point of the saturated carrier gas. Since the concentration of the calibration liquid in the carrier gas can be precisely calculated by measuring the liquid temperature and the pressure of the saturated carrier gas, the response of the analyzer can be calibrated to this known concentration while maintaining the liquid to be analyzed in a liquid state.

Abstract: A cathode-ray tube, i.e., CRT, console having a plurality of CRT display faces with a data display on each CRT being divided among predetermined spatially oriented locations with correlated manually operable switches adjacent to each location area on the periphery of an associated CRT. The switches are used to control the display of additional and detailed information concerning an associated data area either on a CRT adjacent to the switches or on another adjacent CRT. Additional switches are provided on the console to enable an operator to respond to a data display by manipulating these additional switches to effect an adjustment or control of the data being displayed.

Abstract: An interface circuit for a transmission line between a remote transmitter and a central control room instrument includes an operational amplifier. The input of the operational amplifier is derived from the current drawn by the remote transmitter. The output signal of the operational amplifier is applied to control the operation of a transistor current controlling amplifier. The current controlled by the transistor amplifier is drawn from the same source as the current drawn by the transmitter. Because of a feedback connection from the transistor amplifier to the input of the operational amplifier, the output current from the transistor amplifier is a mirror image of current drawn by the transmitter. With that arrangement, both the power supply and the remote transmitter may be grounded without loss of accuracy or reliability.

Abstract: A continuously rotatable shaft is employed in a multipoint recorder for slidably and rotatably supporting a print carriage thereon in order to minimize the friction occurring between the print carriage and the shaft while the carriage traverses the shaft and as a print wheel supported by the carriage is rocked into and out of printing engagement with a record medium. A print pad wheel is provided with characterized gear teeth for meshing with characterized gear teeth of the print wheel. This print pad-print wheel construction allows each of the markers on the outer surface of the print wheel to be brought into proper precise color alignment with an associated colored ink pad formed in the ink pad wheel as the print wheel is directly indexed by a pawl and ratchet drive from one print position to another.

Abstract: A closed system couples the inlet and outlet pressures generated by a centrifugal pump to a pair of flexible diaphragms which seal the flow tube in a pressure rebalance system for measuring fluid flow. The system is filled with a conducting fluid which forms certain resistance paths whose resistance varies with diaphragm position. This resistance change is used to generate signals which control the pump motor to the end that the diaphragms maintain a predetermined position and the pump head is equal to the differential pressure.

Abstract: A pulse duration to current converter wherein the output current is proportional to the duty cycle, or duration, of the input pulse. A first current source is modulated by an input signal while a second current source is held constant by an input reference signal level. The sum of the currents from the first and second current sources are averaged by a filter network to produce an output signal that is subsequently applied to the noninverting input of an amplifier to be amplified thereby. An output signal from the amplifier is converted to a current output by an output circuit driven by the amplifier. The output circuit will operate with maximum load impedances by using a level shifter at the input of the amplifier to shift the level of operation of the inverting input of the amplifier away from a power source level supplied to the amplifier.

Abstract: A skirt, containing a number of spaced apart helical grooves along its outer longitudinal surface and an array of spaced apart perforations therein, is attached at one of its ends to one end of a plug of a cage valve. This perforated multi-helical grooved skirt provides a noise attenuating affect on a fluid as it flows through the valve. This skirt construction allows a portion of the fluid to flow through the grooves and across jets of fluid flowing through and between perforations in the wall of the skirt and in the valve cage to thereby create turbulence in the combined fluids. The grooves are formed between lands that have sharp outer edges, which lands continuously clean foreign matter from an inner bore wall portion of the cage as the unitary plug and skirt is moved between an open and closed position.

Abstract: In a computer system wherein a number of peripheral devices contend with each other for access to a communication bus, a priority selection system is provided. The priority selection system includes priority address code setting means as a part of each of the peripheral devices. A contention bus is provided to which all of the peripheral devices are connected in parallel. Logic means are provided as a functional part of each of the peripheral devices. A logic means are responsive to the setting of the priority address codes to resolve the priority selection among the several contenders. With the logic means and the address code means being a part of the peripheral devices, the selection is independent of card cage slot position or of slot gaps. The system is also independent of the length of the communication bus.

Abstract: A process control system including a control station responds to the departure of a process variable from a set point to provide a direct current signal in a two-wire transmission line in a direction dependent upon the direction of such departure and time-proportioned in accordance with the magnitude of the departure. A solid state power relay that accepts the d-c signal at a single pair of input terminals includes high-current rating triacs that are adapted selectively to be fired by triggering pulses generated in response to the d-c signals to supply alternating current power from a source of single-phase or three-phase alternating current to a heavy-duty motorized valve for operation of the latter in one direction or the other and at a speed in accordance with the signals.

Abstract: A process control system including a control station responds to the departure of a process variable from a set point to provide a direct current signal in a two-wire transmission line in a direction dependent upon the direction of such departure and time-proportioned in accordance with the magnitude of the departure. A solid state power relay that accepts the d-c signal at a single pair of input terminals includes high-current rating triacs that are adapted selectively to be fired by triggering pulses generated in response to the d-c signals alternating current power from a source of alternating current to a heavy-duty motorized valve for operation of the latter in one direction or the other and at a speed in accordance with the signals.

Abstract: A thermal recording instrument has an incrementally advanced thermal web. Selectively energized heating elements record alphanumeric information on the web and a logic circuit insures that the web will advance while the elements are energized in order to prevent sticking.

Abstract: A data communication system for an industrial plant includes a plurality of communication stations which are interconnected by a coaxial cable that is required to pass through one or more hazardous areas. The communication stations are energized from a source of alternating voltage of commercial frequency and are arranged to transmit over and to receive from said cable communicating signals that have frequencies which are substantially higher and that have an energy level which is substantially lower than that of the frequency and energy level, respectively, of the power source. Each of said stations is coupled to the cable by an individually associated intrinsic safety barrier each of which includes an iron core transformer. Each transformer includes a primary winding connected in circuit with the associated station and an inductively coupled secondary winding that is connected between the sheath and the internal conductor of the cable.

Abstract: A capstan drive motor having a integrated motor armature and driving capstan assembly with the capstan being mounted directly in one end of a rotatable center shaft of the motor with the other end of the shaft supporting an armature of the motor. The center shaft is rotatably supported on bearings positioned by adjustable mounts and with one of the bearing mounts having a cantilevered structure for temperature compensation of the shaft and bearing support system.

Abstract: The minimum and maximum values attained by an analog data signal in each of successive sampling periods are determined by alternately operative amplitude detectors which produce and store a corresponding minimum and maximum signal for each of these periods. A generator produces a ramp signal which repeats in each period in synchronism with the sweep of the beam of a fiber optics strip cathode ray tube along the strip thereof. A record sheet is advanced at right angles to this strip. Comparators are operative in each period to compare the stored detector signals of the immediately preceding period with the ramp signal, and to produce an output when the ramp signal exceeds either of the detector signals. An EXCLUSIVE OR gate receives these outputs and unblanks the normally blanked tube beam for a time in each period to produce a line on the sheet extending along the strip between points representing the minimum and maximum signal values for the preceding period.

Abstract: A memory system has a data storage element connected by a first memory read device to a first memory output line and by a second memory read device to a second memory output line. A first and a second decoder are connected to the first and second memory read devices, respectively, to read-out data stored in the storage element in response to read address signals applied to the first and second decoders. A "write" operation is effected on the storage element by a write-in device connected between a data input line and the storage element and energized by a third decoder arranged to respond to a write address signal.

Abstract: An eccentrically rotatable control valve having a spherical shaped valve plug is positioned in a valve chamber to regulate the flow of fluid there through. The valve plug is retained in a loosely captured position by means of a bolt and spring to the end of a valve actuating arm for flexible, swivel movement thereon. This construction enables the plug to be initially rotated from a completely open position into line contact with a part of the valve seat in the wall of the chamber, and to then be jointly tilted and rolled about this seat part into and out of fluid tight surface to surface contact with the entire valve seat. The plug and arm are mounted on and for limited longitudinal movement with an associated valve actuator shaft that extends through the chamber. The latter construction provides a means by which the plug can center itself in a properly seated fluid tight position on the seat in the event that the valve seat is out of properly aligned seating surface engagement with the plug.