Abstract: A sequencer control for controlling the time sequencing of the energization of controlled elements includes a microprocessor unit. A large number of input lines and output lines are uniquely multiplexed into a relatively small number of I/O terminals on the microprocessor. The multiplexing, the sequencing and all of the delays are effectively controlled by the microprocessor.

Abstract: A rotary valve has a valve body with a pair of fluid ports providing fluid exits on a face of the valve body. The fluid ports are connected to corresponding fluid channels in the valve body extending between the fluid ports and fluid inlet connections to the valve body. A fluid control plate is positioned in contact with the face of the valve body and extends across the fluid ports. The control plate has a fluid channel therein which is dimensioned to extend between the fluid ports in one position of the valve plate. The valve plate is axially mounted on an output shaft of a drive motor which is connected to the valve plate by a coupling shaft. The face of the valve body and the contacting face of the valve plates are ground precisely flat and after hard anodizing are coated with a low friction coating such as molydisulphide. The motor is arranged to urge the valve plate parallel to and against the face of the valve body by the weight of the motor and the connecting elements between the motor and the valve.

Abstract: A gray tone recorder uses a selective variation in a recording stylus duty cycle of an electrostatic recording system which recording stylus continues to write at full voltage using a dry toner electrostatically attracted to a recording paper by an electrostatic charge deposited by the recording stylus. The full voltage recording operation produces a high degree of consistency in the gray level density while the duty cycle variation is effective to vary the separation between record segments by producing variable length segments within fixed recording time periods to achieve a gray scale record. The toner is subsequently fixed or bonded to the paper to create a permanent record. Input data codes are compared with a sequence of fixed codes during a writing time period to determine the cut-off point of each write cycle. The system is adaptable for a plural stylii write head by supplying individual stylus write data during each write cycle.

Abstract: An improved means and method for accomplishing floating point calculations in computational apparatus includes a primary microprocessor and a secondary microprocessor, each with its own control ROM. The normal or fixed point calculations are handled by the primary microprocessor under the control of a first segment of the associated control ROM. When a floating point calculation is called for, a second segment of that ROM is addressed. The addressing of the second segment of the first ROM also effects the coincident addressing of the ROM of the secondary microprocessor. For floating point calculations, the exponent portion of the numbers being manipulated is handled by the primary microprocessor. Simultaneously therewith, the mantissa portion of the numbers being manipulated is handled by the secondary microprocessor under the control of its associated control ROM. The resultant calculations are recombined in the primary microprocessor to produce a complete solution for the floating point calculation.

Abstract: A mounting arrangement for magnetic record transducers wherein a single locking screw is provided for clamping each transducer in position. Additionally there is provided, for each transducer assembly, a pair of adjusting members such as set screws, each of which has an eccentric boss projecting from the end thereof. Each of the adjusting screws fits snugly in a correspondingly threaded hole in the mounting bracket while the eccentric pin or boss cooperates with a longitudinally oval recess in the end of the transducer assembly. The external end of each of the adjusting screws is keyed to indicate the relative position of the eccentric boss at the opposite end thereof. The two adjusting screws are positioned on opposite sides of the clamping screw and are effective to provide both lateral and angular adjustment of the transducer relative to the mounting bracket. When the transducer is properly adjusted, the locking screw is tightened to clamp the transducer in position.

Abstract: A tape transport speed control uses a synthesized clock signal primarily derived from playback data signals in a preselected primary data track. Data signal drop-out in the primary data track used to produce the synthesized clock signal is monitored by a digital logic circuitry which is effective to borrow secondary derived clock signals from an adjacent data track on the same tape. The borrowed secondary synthesized clock signals are used during the drop-out interval on the primary data. The handover of the borrowed clock signals from the adjacent track and the return to the clock signals derived from the primary track is performed automatically by a sensing of the start and end of the drop-out.

Abstract: A tape cleaner for cleaning debris from the surface of a recording tape uses a tape wiping or cleaning medium advanced across the surface of the recording tape at a speed correlated with a selected speed of operation of the recording tape. The tape wiping medium may be in the form of cleaning tape driven between a supply reel and a take-up reel by a stepping motor driving the take-up reel at a sub-multiple of the selected recording tape speed. Thus, the speed of the cleaning medium is automatically selected by selection of the recording tape speed, and, to minimize the usage of the cleaning medium, the cleaning medium is driven at a predetermined fixed ratio of the recording tape speed.

Abstract: An air conditioning system for providing an air cooling operation during a load phase management shutdown of the air conditioning compressor utilizes a thermally insulated cold water tank for storing chilled water. The water is cooled by a free cooling effect using wet bulb temperature drop of a refrigerant circulating between a secondary coil in a condenser section of the air conditioning system and a heat exchanger in the chilled water tank located below the condenser. The secondary coil in the condenser is cooled by a waterspray which can advantageously be derived from the condensate obtained from the evaporator section during a compressor operation phase of the air conditioning system. The chilled water is supplied to a chilled water coil in an evaporator section to cool the air flow in a chilled water cooling operation when the air conditioning compressor is inoperative during the load management phase of the peak hour of the air conditioning system.

Abstract: A butterfly valve having a valve body and a valve disc which is selectively rotated to produce a fluid-tight engagement of a peripheral edge of the disc with an annular seal or wall defined by a portion of an internal fluid passage in the valve body uses an annular fluid pressure seal member mounted in an annular groove in the valve body adjacent to the annular seat. The seal member is a layered structure including a pair of coaxial metallic annular seal rings having aligned J-shaped inner sides arranged in a facing relationship and a resilient annular seal ring captured between the metallic rings and having a sealing surface aligned with an outside surface of the J-shaped sides. The sealing surface of the resilient seal ring and an outside surface of the J-shaped sides are arranged to produce the fluid-tight engagement with the peripheral edge of the valve disc.

Abstract: A temperature sensor uses a thin film structure having an RF sputtered layer of a temperature sensitive material forming a thermistor element deposited on an electrically insulating and thermally insulating substrate. The sensor may include a plurality of deposited thermistor layers arranged on both sides of the substrate and having electrical connection means attached thereto. The sensor is arranged on a substrate suitable for inclusion in a detector cell forming a chamber arranged to be connected to a source of fluid flow.

Abstract: A method and apparatus for process control of batch processes utilizing the steps of storing in a memory the actual measured values of the process variable and utilizing the memorized values for an estimative operation to determine the timing for supplying a manipulated variable to the process. Thus, the process control apparatus of the present invention commits to memory the actual measured values of the process variable, utilizes the memorized values for the estimative operation to determine the point of time for suspending the supply of the manipulated variable and the point of time for starting the regular constant value control and, based on the outcome of this estimative operation, effects the separation of the process control under the steady condition from the control under the transient condition. Such a control operation ensures that the control value is not increased beyond its limit and, at the same time, it permits the adjusting period to be reduced to the minimum.

Abstract: A combustible gas analyzer for determining the Wobbe Index of a combustible gas uses a constant pressure combustible gas supply and constant flow rate air supply to provide oxygen and gas for combustion. The air is supplied directly to be mixed with the combustible gas while the gas is passed through a variable orifice or valve before mixing with the air supply. A zirconium oxide detector is arranged to measure the oxygen content of the combustion products to enable a predetermined oxygen level to be reached. The valve is operated by a valve control response to the output of the zirconium oxide detector to maintain the preset oxygen level. The position of the valve is monitored as a representation of the Wobbe Index of the combustible gas.

Abstract: A tape transport speed control uses a speed controller supplied with packing density or digital bits per inch of recording medium and data rate or digital bits per second to compute the speed of the tape which would conform to these selected parameters by the speed being equal to the data rate divided by the packing density. The speed controller uses a combination of digital and analog circuits to produce a reference signal and a speed select signal for the tape transport speed control operation using a comparison between the reference signal and a tachometer signal to control the tape transport about the basic selected tape speed.

Abstract: A combustible gas analyzer for determining the calorific content of a combustible gas uses a constant flow rate air supply and a constant pressure combustible gas supply to provide oxygen and gas for combustion. The regulated air is supplied directly to be mixed with the combustible gas. On the other hand, the combustible gas is passed through a series connection of a pressure regulator and a variable orifice or valve before mixing with the air supply. A feedback pressure to control the pressure regulator for the gas is obtained from the output of the valve. The mixture of air and gas is burned in a combustion chamber, and a zirconium oxide detector is arranged to measure the oxygen content of the combustion products to enable a predetermined oxygen level to be reached, e.g., stoichiometric combustion. The valve is operated by a valve control apparatus responsive to the output of the detector to maintain the preset oxygen level.

Abstract: A tape drive capstan has a porous ceramic matrix in the form of a cylindrical shell using spherical ceramic particles bonded together to form a network of interstitial pores which are substantially uniform in size and interconnected. A urethane elastomer is impregnated into the pores to form a tape driving surface on the outside surface of the cylinder. The outer surface of the capstan is finish-ground to an outside diameter suitable for use in a tape drive apparatus. The particles occupy approximately 70% of the internal volume of the shell and the elastomer occupies the remaining 30%. The shell is attached by an epoxy to an outside surface of a drive shaft suitable for driving the capstan.

Abstract: In an electronic thermostatic circuit, a resistive bridge network is employed to sense the level of the ambient temperature. The bridge includes three legs having fixed resistors and one leg having a temperature sensitive resistor as well as a serially connected adjustable potentiometer. The adjustable potentiometer is adjustable to provide a selected set point for the operation of the thermostat within a given range of temperatures. The adjustable potentiometer is provided with a shaft to which an adjusting knob having a pointer thereon is secured by means of a slip fastener. Calibration of the assembly is accomplished by turning the knob with its pointer pointed in a preferred direction then holding the knob while adjusting the shaft and the associated potentiometer until the bridge output corresponds with the value indicated by knob pointer.

Abstract: A delta modulation circuit features a variable input voltage which is compared periodically with a quantized previous signal sample, resulting in a digitized output. The digitized output of the comparison controls the selective operation of a switching control circuit which, in turn, is clocked at a predetermined rate. The switching control circuit selectively applies a positive or a negative reference signal to the input of the quantizer from a common voltage reference source. A quantum charge is derived from the signal reference source then, through selective switching, that quantized charge is transferred in a positive or a negative direction to the input of a quantized charge memory device, resulting in the quantized last signal sample.

Abstract: A programmable signal equalizer uses a plurality of active RC circuits arranged to be controlled by a ladder resistor network. The resistor ladder circuits are selected by digital word signals representative of the selected magnetic tape speed to produce a signal equalization operation at each of the selected tape speeds. A combination of the ladder network circuits is selected by the digital bits in the digital word to form an active RC circuit producing a signal equalization correlated to a selected tape speed. Using an eleven line digital word code and an eleven RC ladder, eight master speed equalizations are selected as well as seven equalizations between the master speeds for a total of sixty-four equalization functions.

Abstract: A terminal block connector uses a first nut having an internal thread of a first diameter and type and a second nut coaxially arranged therewith having an internal thread of a second diameter and type. To further the universality of the connector, the first thread may be an SAE thread while the second thread may be a metric thread, while the first diameter is always smaller than the second diameter. The first nut is arranged to cooperate with a first diameter machine screw while the second nut is arranged to cooperate with a second diameter machine screw. The two nuts are held rotationally captive in a coaxial recess in an electrically insulating block with the larger thread diameter second nut located at the entrance to the recess. The smaller thread diameter first nut is initially positioned beneath the large diameter second nut and in frictional engagement with the wall of the recess with a space between the first nut and the bottom of the recess.

Abstract: There is disclosed herein an apparatus for displaying data and communicating with another data processing device via a parallel port or over a long distance communications network via a full duplex modem, said computer terminal utilizing a microprocessor for programmed control of the terminal. The terminal is capable of displaying information on a standard black and white television set and utilizes a keyboard for entering information to be displayed or sent to the main data processing system. Limited graphics with sixty four graphics patterns are also available by using the microprocessor chip to scan the keyboard and communicate with the modem and parallel ports, and by utilizing a standard television set instead of a cathode ray tube, substantial material cost savings can be made in building the terminal which could be built for under $250 in parts in 1979.