Abstract: A yarn of a synthetic, fibre-forming, polymeric material comprising a plurality of filaments having a substantially rectangular cross-section and having a birefringence assymetry across the width of the filaments, each of the filaments being twisted about the longitudinal axis of the filament in such a manner that the overall lateral dimension of the twisted filament corresponds substantially with the length of the rectangular cross-section of the filament.

Abstract: A specially designed multifilament textured yarn has alternating twists therein. A woven or knitted fabric manufactured from the yarn has a handling similar to that obtained by a hard twist yarn or a true twist yarn and provides pattern with a heather like feeling.In the yarn, S-twist yarn portions and Z-twist yarn portions are alternatingly distributed along the length of the yarn but the non-twisted portion is substantially not included in the yarn. Either S-twist yarn portions or Z-twist yarn portions have a compact twist yarn structure, and the other portions have a bulky twist yarn structure.

Abstract: An electrothermal hydrazine thruster passes the hydrazine through a catalyst bed and an augmentation heater. The augmentation heater includes an electrical heating element powered by a satellite battery. A load resistance is coupled in series with the heating element to reduce the current through the electrical circuit including the heating element to a safe level. A switch coupled across the load resistance is closed bypassing the load resistance when the heating element heats up and increases its resistance value to a value that can be tolerated in the battery circuit.

Abstract: A fluid flow control system has a capability of operating selectively in a power matching mode, in which power consumption is low, and a maximum flow mode in which high responsivity and high speed features can be appreciated. For this purpose, a mode selector valve is used to switch the system between these two modes.

Abstract: A load responsive fluid power and control system in which the speed of the prime mover, driving a fixed displacement pump, is varied to maintain a constant pressure differential between pump discharge pressure and maximum system load pressure, above a certain predetermined system flow level and in which this constant pressure differential is maintained by pump flow bypass control, at system flows below this predetermined level.

Abstract: In an air storage power station heat is withdrawn from the compression process via a heating element (18) and passed into a heat storage device (15). During turbine operation the cold compressed air taken from the air reservoir (1) is first pre-heated with the stored heat in an air heater (21) and then passes via the recuperator (14) to the gas turbine (12',12"). In this way low-temperature corrosion at the exchange surfaces of the recuperator (14) on the flue gas side is avoided, especially during start-up of the gas turbine.

Abstract: A cold storage body that comprises a hermetically sealed vessel made of aluminum alloy in which a cold storage medium in an appropriate amount is enclosed with a space remaining within the vessel filled with a compressed inert gas at an appropriate pressure. The vessel may comprise a can type trunk portion of a thin aluminum sheet having an open end with a cover member closing the open end of the trunk member. The thus formed cold storage body has sufficient strength regardless of temperature variation for cooling the cold storage body as well as a long durability and a high corrosion resisting property.

Abstract: An air ventilator for ventilating indoor air to the environment comprising a motor provided with a shaft, a rotor mounted on said shaft, a plurality of fan blades pivotally attached to the rotor, a rotating circular plate having a plurality of sliding slots and a plurality of connecting holes mounted on said shaft of the motor, a fixed circular plate connected to the rotating circular plate with pins and mounted on the shaft of said motor, centrifugal weight members disposed between the fixed circular plate and the rotating circular plate, and a torsion coil spring connecting the centrifugal weight member with the rotating circular plate for elastically supporting the weight member, whereby when the motor is operating, the centrifugal weight members engage the rotating circular plate, apply a circumferential directional force thereto, and angularly displace the circular plate, said displacement being transmitted to the fan blades for ventilating the inside air to the environment; and when the motor is not ope

Abstract: A refrigeration system is disclosed which may have multiple compression and condenser stages, in which an electronic refrigerant expansion valve is controlled by the digital output of a microcomputer which adjust the expansion valve in response to a valve change signal which is a function of a fraction of the deviation of the sensed refrigerant superheat from a desired superheat added to a multiple of the computed rate of change of the refrigerant superheat.

Abstract: An incrementally adjustable electronic expansion valve for precisely controlling refrigerant flow through the valve is disclosed. Basically, the expansion valve includes a stepper motor, a sleeve member, and an orifice assembly. The sleeve member is incrementally moved over a slot(s) in the orifice assembly by operation of the stepper motor to control refrigerant flow between an inlet and an outlet of an expansion valve. A control system provides electronic digital control signals to the stepper motor to control operation of the motor in response to superheat of refrigerant flowing from an evaporator to a compressor of the refrigeration system. The electronic expansion valve may also include sealing means to substantially prevent refrigerant flow through the valve when the sleeve member is in its fully closed position.

Abstract: An air conditioning system for a vehicle of the type having an engine which produces heat conveyed from the engine by an exhaust system, a water circulation system and an oil circulation system, comprising a heat engine including a refrigerant circulation system and a refrigerant circulation subsystem. The refrigerant circulation system is connected to at least one of the heat conveying systems from the engine such that the refrigerant in the refrigerant circulation system is heated. The heat so received drives the refrigerant in the refrigerant circulation subsystem by means of an ejector. Expansion of refrigerant in the refrigerant circulation subsystem provides air conditioning through a load evaporator. The refrigerant circulation system is preferably connected to the vehicle engine to obtain synergistic use of the engine water pump, radiator fan, oil circulation system and exhaust circulation system.

Abstract: The apparatus includes a condenser (4), through which passes a duct (3") that carries, downward, the fumes from heating boiler (1) to bring them into a lower chamber (5). The fumes are mixed with ambient air in this chamber (5), a mixture that is then moved upward, going through the evaporator (4) by the action of a fan (9), placed contiguous to the collection chamber (10), placed above the evaporator (4). Together with the recovery of heat from the fumes there is a recovery of the heat contained in the ambient air. Besides the high efficiency that can be obtained with a limited capital investment, in the case of fumes the apparatus purifies them of the solid particles in suspension and even noxious gaseous components. The apparatus is used independently of the hot gas, for example, to heat water for domestic use. The air that is exhausted by the fan (9) after having given up its heat inside the evaporator (4) can be used for conditioning a closed area.

Abstract: A refrigerated display case is provided which includes a framework having a plurality of first panels connected to each other to form a structure having a polygonal cross-section. Each first panel is connected to an adjacent first panel such that an extending portion of the first panel extends beyond its connection point to an adjacent first panel. The framework also includes a plurality of second panels, each second panel being connected at one end to an extending portion of a first panel. The framework defines a plurality of refrigeration compartments. Each compartment includes an information board to provide information relating to the products displayed in the compartments.

Abstract: A device for regulating the length of thread absrobed by a knitting machine and/or for correcting the variations in tension of a thread supplying a textile machine, is disclosed. The device comprises a tensioning means of any type, a drive member whose rotation results in the movement of the tension-generating member of the tensioning means, a feeler element over which the thread passes and which is moved when the length of thread absorbed and/or the tension of the thread varies and two switches, one controlling the placing in rotation of the drive member in one direction and the other the placing in rotation in the other direction. The direction of rotation of the drive member is selected so that the corelative action of the feeler corrects the variation in the length of thread absorbed and/or of the tension which is the cause of triggering this rotation.

Abstract: The invention relates to a yarn handling arrangement in which the yarn is subjected to conditioning in a humid atmosphere before and as it is drawn off for use in a textile machine. The apparatus described in an example consists of an enclosure comprising a housing, in one compartment whereof are a plurality of pairs of bobbins on support rods, another compartment being defined by a sleeve member which is kept constantly moist by a water distributing device. A flow of air is arranged to fill the sleeve member and to escape therefrom through slots provided at levels corresponding to each of the levels at which the bobbins are supported.

Abstract: A U-shaped part (1) of which the two parallel branches (1a, 1b) may slide in corresponding grooves (9a, 9b) of a casing, forms a key receiver ring. In a chamber (13) of the casing (2) there is provided a mechanism comprising an oscillating part (3) provided with a spring blade (11) and having a series of notches (14) forming latch locks. The free end of the longer branch (1b) of the U-shaped part (11) is provided with a bolt (4). A maneuver button (10) allows to oscillate the oscillating part (3) against the action of its spring (11) to disengage the bolt (4) of the latch lock (14) where the spring was keeping it engaged, thereby allowing to disengage from the casing (2) the shorter branch (1a) of the U and to bring the bolt (4) selectively facing one of the latch locks (14) so that the length of the portion of the ring (1) being outside the casing corresponds to the number of the keys engaged on that portion.

Abstract: The disclosure relates to a key keeper comprising a key-retaining loop 3 with an opening 17 for the receipt of keys; said loop is connected to a loop holder 2 being slideably mounted within a housing 1. The loop is being closed if the holder is in its slid-in position, whereas the loop can be opened if the holder is partially slid out of the housing. Means are further provided for locking the holder in its slid-in position.The means for locking the holder consist of a wheel 4, which is rotatably mounted in the housing, the rotation of which can be prevented by a snap connection 11. By rotating the wheel 4, the loop holder is displaced in or out of the housing 1.

Abstract: Methods of and apparatus for controlling the gap between a mandrel and an extrusion die during extrusion wherein upon the actual gap between the mandrel and die during extrusion being detected as being larger than a predetermined gap, relative movement between the mandrel and die is produced to close the actual gap and establish the predetermined gap, and upon the actual gap between the mandrel and die during extrusion being detected as being smaller than the predetermined gap, relative movement between the mandrel and die is produced to open the actual gap and establish the predetermined gap.

Abstract: The hot working method using a swaging machine provides for the minimizing heat transfer by the heat conduction from the preheated dies and work through the surrounding mechanical power transmission parts during the swaging process for the workpiece. The swaging machine has a die section including pairs of die elements and curved-profile buckers, the die elements having the working ends exposed toward the center beyond the inner sides of the corresponding buckers and the die elements and buckers being held together by means of steel balls, the motor-driven sectorial spindles for driving the die working section for rotation, the spindles and buckers being held together by means of steel balls, and springs for biasing the die working section toward the outside.

Abstract: Machine permitting a deep slitting in a periphery of non planar discs for obtaining wheels carrying a pneumatic tire, wherein the disc to be slit is driven in rotation on a floating support, that is a support which automatically compensates for flatness irregularities while slitting knurling means are mounted on a driving device which is rigidly supported on a fixed frame.

Abstract: A wire coiler comprising an elongated coil support, gripping device holding the coil support for rotation therewith, a drive connected to the gripping device for rotating the gripping device, the drive having an axis extending parallel to the direction of elongation of the coil support, a control for the drive, a device for guiding and feeding the wire to the coil support, and an adjustment drive connected and responsive to the rotating drive control, the adjustment drive cooperating with the wire guiding and feeding device for adjustably positioning the same in directions parallel to the direction of elongation of the coil support and relative thereto.

Abstract: A method for continuously producing a core member to be embedded within a trim, comprises the continuous steps of forming slits in a band-shaped metallic plate by means of slitting rolls, elongating the slit metallic plate by means of elongating rolls and pressing the elongated metallic plate by means of finishing rolls.

Abstract: A grip-feed machine for gripping a material in the form of strip or the like and feeding the gripped material in a bending machine which has a sun gear, comprising: a guide bracket having a guide shaft securely received therein; a cradle member having lower and upper portions and movable axially forwardly and backwardly on and along the guide shaft and formed at the lower portion thereof with a rack gear in parallel to the guide shaft; a gripping mechanism for gripping the material and feeding the gripped material in the forward and backward directions of the guide shaft; a pinion gear held in mesh with the rack gear of the cradle member; a direct current servomotor for driving the pinion gear to rotate about an axis thereof; an angular position detector having mounted thereon a detecting gear which is held in mesh with the sun gear and adapted for detecting the angular position of the detecting gear to produce a pulse signal indicative of the angular position of the detecting gear; and control mechanism for

Abstract: This invention contemplates a rapid method of calibrating probe-pin combinations, such as star probes or rotary-swing probes, which method is applicable when the probe system forms part of or is coupled to the control system of a measuring machine wherein a self-centering probe of workpieces is possible. The calibration procedure employs a calibration standard having a plurality of probe-centering elements distributed over its surface and facing in different directions, the positional geometry of these elements being stored in the computer of the measuring machine. Each of the individual probe balls is successively introduced into a centering element which is accessible. Thereupon, the position of each ball-center point is determined in the computer, from the stored positional data and the pre-established diameter of corresponding probe balls.

Abstract: An hydraulic proximity probe arrangement for determining the spacing of the surface of a rotating body from another fixed body as it rotates in a fluid medium. The body is provided with a plurality of circumferentially and equally spaced surface irregularities of like size and shape, such as indentations or projections, and at least a pair of probes are circumferentially spaced around the body, each being axially spaced an equal distance from the body's surfaces when at rest. The probes pick-up pulsations in the fluid medium caused by the rotating body, the amplitudes of which are indicative of the spacing of the surface of the rotating body from the end of the probes. These pulsations are signalized and the resultant signals are compared with calibrated deviation signals to provide data indicative of the spacing of the body's surface from a reference point during rotation of the body.

Abstract: An improved method of measuring leak rates by placing a source of fluid pressure in communication with a cavity being tested, and measuring the flow rate to the cavity after a predetermined time to determine the leak rate from the cavity. The improved method achieves a determination of the leak rate in a shorter time than that required to establish steady state flow conditions between the pressure source and the test piece cavity. The improved method measures the flow rate to the test piece cavity at a much earlier time after pressurization of the cavity than normally required to establish such steady state conditions, and applies a previously generated calibration function based on a linear correspondence between the measured flow rates and the steady state flow rates.

Abstract: A method for determining the erosion of a borehole or cavity by providing a source of liquid inert gas, preferably nitrogen, placing the inert gas in a storage tank, and suspending the storage tank so that one may determine the actual weight of the nitrogen as it is withdrawn from the tank in liquid state. There is further provided hydraulic elements for lifting or lowering the storage tanks suspended from a weight cell as a tank is placed into use or non-use. Further, the liquid nitrogen is pumped from the storage tank with the use of a reciprocating pump, and converted into gaseous nitrogen (in the state of 100.degree. F.) and is injected into a borehole or the like. The nitrogen gas is then allowed to flow under a certain pressure down the borehole, and due to the properties of nitrogen gas, the nitrogen interfaces at a horizontal plane as it moves down the borehole.

Abstract: A storage tank system especially useful for storing liquid gasoline comprises a rigid inner tank encased by a flexible outer jacket with a leak detecting means associated with the closed space between the inner tank and jacket. The system results in a storage facility which is less likely to lose its stored liquid to the environment due to a slow leak or a sudden large leak such as is possible with an earthquake.

Abstract: The invention concerns a press for the testing by means of internal pressure of tubes provided with threaded ends, in which end pieces screwed in a pressure medium-tight manner on the tube ends are inserted into the sealing heads of the press. The end pieces are cap-like and have radially arranged connecting boreholes so that the pressure medium feed is radial in contrast to the axial pressure medium feed of the familiar constructions. No appreciable axial forces thus arise between the tubes and the test heads. In addition, the outer end of the cap-like end pieces facing away from the tube serves for the coupling of a shaft, which can displace the tube with the end piece axially and act upon it with a torque. Furthermore, the sealing head is readily detachable in a like manner in a retaining head and is inserted pressure medium-tight to the outside, just as the end pieces in the sealing heads.

Abstract: The determination of the surface tension of a liquid or of the interfacial tension between two immiscible liquids is effected by drainage methods in which the movement of an air bubble or a droplet of the lighter liquid is observed, certain measurements made and the surface tension or interfacial tension determined from such measurments. The apparatus used, comprising a tapered tube, a rotating uniform diameter tube or a tilted uniform diameter tube, is simple and inexpensive and accurate measurements are obtained.

Abstract: An installation for the indication of the fuel consumption, especially of heavy truck engines, with a sensor for the position of the drive pedal and with a set of fuel consumption-engine rotational speed-characteristic curves stored in a storage device and dependent on the drive pedal position; a predetermined number of at least single-color light diodes, of which each is coordinated to a predetermined partial range of engine rotational speed and indicates an information about the specific fuel consumption as a function of the instantaneous control rack, respectively, throttle valve position coordinated to the drive pedal position within the engine rotational speed partial range corresponding to the stored set of fuel consumption-engine rotational speed curves, are integrated into the dial of a tachometer corresponding to their coordination to the predetermined engine rotational speed partial ranges.

Abstract: A device for testing fuel injectors in situ. The device comprises a detector (10) having a piezoelectric crystal (50) which converts mechanical impulses caused by the fuel injector valve needle snapping back onto its seat onto electrical signals. The signals are fed to electronic processing means (15) which detects the signal amplitude and displays it on an LED bar graph display (2) as an indication of the operating efficiency of the fuel injector. A timing system using the detector (10) as a generator of timing signals is also disclosed.

Abstract: In a method for performing a step rate test on an injection well, a portable pumping unit is employed to increase the pressure on the injected water to a predetermined level in order to carry out the step rate test, and the predetermined pressure and flow rate are maintained and controlled by separating a portion of the pressurized water outflow from the portable pump from the main stream thereof, and the separated portion of pressurized water is returned to the water storage tank which feeds the input to the portable pump.

Abstract: A system which enables the measuring, testing and accounting for a fluid, preferably oil, as stored in a tank battery adjacent a producing oil well system. In its most basic form, the system includes a master control unit associated with a level transducer for each tank, basic sediment and water monitors for various conduits within the system, temperature sensors for each tank and the various conduits, and a data collection box for transferring data stored in the master control unit after a predetermined amount of time has transpired. Several options are available with this system and these include telemetry options for remote reporting of the various parameters of the system and various alarm and theft prevention devices.

Abstract: An electronic anemometer for measuring air mass flow in a conduit having a straight length of temperature-dependent resistive wire; a circuit board for holding at least a portion of the electronic circuitry used when the anemometer is operating to maintain the wire at a substantially constant temperature and generate an air mass flow-indicating signal based upon the air mass flow in the conduit sampled by the wire, the circuit board being mountable on the exterior of the conduit; a rigid support plate having a pair of spaced-apart openings, the plate being fixedly attached to the circuit board; a pair of electrically nonconductive support inserts, each of the inserts being fixedly retained within one of the openings in the support plate; and a pair of electrically conductive, resilient posts capable of withstanding the elevated operating temperatures encountered when the anemometer is operating, each of the posts having a wire-supporting end portion fixedly connected to the wire, the end portions being spaced

Abstract: A constant temperature anemometer having an enhanced frequency response. A sensor element is included within one leg of a bridge circuit with a feedback circuit being operatively connected to the bridge circuit. The bridge circuit frequency response is shaped by impedance elements connected in parallel with another leg of the bridge circuit. In a preferred embodiment, the impedance elements include serially connected resistance and capacitance elements.

Abstract: Air filtering apparatus includes a filter cell having ionizing and collecting structure, a high voltage power supply and control unit for supplying a high voltage to the filter cell, a separate low voltage power supply unit for supplying operating power to the high voltage power supply unit and a separate probe unit for monitoring the flow of air within a duct in which the filter cell is installed. The high voltage power supply and control unit includes an output transistor in series with a primary winding of a step-up transformer and controlled by an oscillator circuit which is operative to control and limit the output voltage and current and also the current through the output transistor. The probe unit includes a pair of thermistors and a bridge circuit and operates to provide a signal which is independent of variables other than air flow velocity. A modified apparatus is also disclosed, arranged for portable use and arranged for energization from a standard power line with no separate low voltage supply.

Abstract: A simple device for measuring flow rate of liquid in a partially-full pipe. This device comprises a generally vertical, first chamber into which liquid is introduced, a non-opaque, second generally vertical chamber in communication with the lower portion of the first chamber, an orifice communicating with the lower portion of the first and second chambers, an overflow leg and an outlet for liquid passing through the orifice or overflow. The height of liquid in the second chamber provides a visible indication of the flow rate.

Abstract: An acoustic system is provided for measuring the fluid level in oil, gas or water wells under pressure conditions that does not require an electrical link to the surface for level detection. A battery powered sound transmitter is integrated with a liquid sensor in the form of a conductivity probe, enclosed in a sealed housing which is lowered into a well by means of a wire line reel assembly. The sound transmitter generates an intense identifiable acoustic emission when the sensor contacts liquid in the well. The acoustic emissions propagate up the well which functions as a waveguide and are detected by an acoustic transducer. The output signal from the transducer is filtered to provide noise rejection outside of the acoustic signal spectrum. The filtered signal is used to indicate to an operator the liquid level in the well has been reached and the depth is read from a footage counter coupled with the wire line reel assembly at the instant the sound signal is received.

Abstract: The tubes of tube and shell heat exchangers destructively vibrate at certain velocities with which fluid flows over their outside surfaces. An acoustic generator is positioned to respond to the fluid vibrations generated by the tubes. The structure of the acoustic generator is sized and arranged to produce a modulated tone representative of tube vibration. A detector mounted external the heat exchanger shell responds to the tone to initiate corrective action which will reduce the tube vibration.

Abstract: A resonant sensing device for measuring the hardness of a workpiece to be tested includes a diamond tipped rod adapted to be resonant and for determining the hardness of a workpiece to be tested is brought into forced contact with such workpiece. The difference in resonant frequency of the rod between its not-constrained condition and its constrained condition (forced contact) is a measure of the hardness of the workpiece. The present invention describes a circuit wherein during a first time interval an up/down counter accumulates the counts arising from the oscillations of the not-constrained rod. During the ensuing interval of the same duration, the counter counts down the accumulated count responsive to the oscillations of the constrained rod.

Abstract: A first array (A) of ultrasonic transducers transmits ultrasonic shear waves circumferentially around an examined cylindrical object (110). A second array (B) transmits ultrasonic shear waves axially along the examined object. Triggering pulses from a triggering amplifier (22) are switched by a multiplexer (24) to each individual transducer of the first and second arrays. As one of the transducers assumes the role of a transmitting transducer and transmits an ultrasonic wave, the other transducers of the first and second arrays assume a receiving mode to receive reflected ultrasonic components. A wave travel timer (26) measures the duration for an ultrasonic wave to be transmitted from the transmitting transducer to a defect and for a reflected component to propagate from the defect to the receiving transducer.

Abstract: A series of pulses are transmitted to a first laser and the same series of ulses through a time delay network to a second laser. Each laser provides pulses of light through separate diagonal mirrors and through respective transparent holograms. Each light beam is then brought into convergence by respective sides of a wedge shaped reflector and brought into spacially coincident focus by an imaging lens onto the surface of a sample under test. The two hologram transparencies are imaged spacially coincident but separated in time on the face of the sample. Thermal elastic waves produced by laser heating at the sample surface transform into a desired acoustic beam pattern determined by the nature of the wavefronts which the hologram transparency represents. The position of the coincident image on the sample may be moved by varying the time between the two pulses.

Abstract: Probe for the nondestructive testing of cylindrical cavities, including a rotatable testing head, an outwardly cylindrical housing supporting the testing head, a motor disposed in the housing for driving the testing head, a shell body being surrounded by the housing and being in the form of a semi-cylindrical part with a relatively smaller diameter in vicinity of the motor, a tube sealing the shell body in vicinity of the motor, and means disposed on the shell body for securing the motor in a definite position.

Abstract: An ultrasonic transducer in which a plurality of elements are employed alternate ones of which are utilized as transmitters and receivers and having the same area but in which the transmitter elements are composed of material having a high transmit sensitivity while the receiver elements are composed of a material having a high receive sensitivity.

Abstract: An improved transceiver for use in ultrasonic echo-ranging systems is disclosed together with a system for its use. The transceiver comprises a capacitor to store power received from a central location during an inactive mode, and switching means to disconnect the capacitor from the power supply during the active mode. The capacitor is used both to supply power to an electrostatic transducer to generate an ultrasonic pulse and also to provide a noise free bias voltage to the transducer to enable it to receive the reflected pulse. An amplifier is provided as part of the transceiver so that long transmission lines between transceiver and controller are possible without undue noise. The power supply line can also be used as the signal transmission line and can be provided in a simple two-wire shielded cable, the other wire being used for logic level control signal transmission, thus allowing simplified multiplexing of a plurality of transceivers.

Abstract: A dark-field magneto-elastic non-destructive testing technique for detection of defects in a conductive material by inducing eddy currents or applying an electric current to the material along a path in such manner that the current will be diverted from the path in the vicinity of any material defect, causing the generation of acoustic waves locally from the interaction of the diverted current with a local magnetic field. The resulting acoustic waves are detected as an indication of the presence and location of a material defect. In typical application, a current is induced in the conductive material by the generation of eddy currents in the material along a substantially linear path by coupling from a current excited wire insulated from and applied near the surface of the material. The eddy current will tend to follow substantially the direction opposite of the current excited wire.

Abstract: A capacitive sensor for use in the measurement of pressure or pressure changes of a fluid medium which sensor maintains the capacitor electrodes in a substantially parallel relationship. Maintenance of this parallel relationship provides a substantially linear capacitive output over a given range without further electronic buffering or calibration. The capacitive signal may be enhanced or amplified by use of multiple parallel plates which are movable simultaneously with deflection of the flexible diaphragm.

Abstract: A device for, and a method of, applying an incremental strain to a test specimen of a solid propellant which is at the stress-free temperature, while simultaneously subjecting the test specimen to an incremental temperature change above and below the stress-free temperature. The device includes a frame assembly in which a captive "strain multiplier" is used to apply the thermally induced loads to the test specimen of the solid propellant that is mounted within the device. Temperature changes, above or below the stress-free temperature, cause volume changes of the rubber members of the "strain multiplier" and result in the "strain multiplier" axially loading the mounted test specimen in simulation of the loading conditions that occur in a case-bonded solid rocket grain. When the temperature is raised, the rubber members expand and exert an axial compressive load on the mounted specimen; and, when the temperature is lowered, the rubber members contract and exert an axial tensile load on the mounted specimen.

Abstract: A differential pressure gauge 10 utilizes a piston member 18 provided with a series of grooves 19 right around it, so that the piston member 18 itself forms the rack of a rack-and-pinion device (pinion 22) for converting linear displacement of the piston member into rotary displacement of the pinion. For sensitivity and accuracy, the seal between the piston member 18 and the passage 13 is a hard-surface-to-hard-surface engagement between substantial (total) hard surface areas at any one time of the passage 13 and the piston member 18, including regions of the surface area of the piston member 18 intermediate mutually adjacent end ones of the grooves 19. In this way, the gauge is insensitive to the base pressure, there being no soft seals to deform under pressure. A magnetic coupling is used through the wall of the housing, which can thus be made completely pressure-tight.