Abstract: A temperature sensor is formed by mounting a force-sensitive resonator on a resilient or non-resilient base structure, preferably in an enclosure such that thermally induced expansions or contractions of the base structure apply a stress to the resonator. The resonant frequency of the resonator is measured to provide an indication of the temperature of the base structure and resonator.

Abstract: Measurements of the gravitational field are made by generating a frequency representative of the gravitational field. In one aspect, the frequency is generated by oscillations in a magnetic vibrator formed by magnets having vertically opposed magnetic poles.

Abstract: A transducer (51) extended by an electroexpansive longitudinal effect, actuates a lever (77) through a bendable plate (56). Preferably, the plate actuates a first arm (53) having an end which provides the fulcrum. Another bendable plate (79) actuates a second arm (76) having an end which exterts the power to the lever. The plates are symmetrically disposed on both sides of the transducer axis. The lever is differentially actuated by the arms. When such lever actuators are combined into an impact printer head, a guide for printing elements carried by the respective levers are preferably used in preventing the levers from excessively excursing.

Abstract: A cast string-type measurement cell, including a metallic string member having cast thereto nodal masses, clamping elements, and spring and suspension elements, thereby to define an integral structural assembly that may be formed by a casting mold in substantially finished condition ready for installation in the measuring apparatus. Preferably, the string is formed of an amorphous metal, and the cast components comprise a glass-fiber-reinforced synthetic plastic material.

Abstract: A very sensitive force or vibration indicating device is claimed and made by the use of the movement of a ferramic rod or slab of a microwave resonance ferramic gyrator in operation with microwave energy. The movement of the ferramic rod or slab is mechanically connected to a force or vibration source. The varied detected output of microwave energy produced by a phase shift caused by the gyrator is detected as a very sensitive indication of force or vibration applied.

Abstract: A motion sensing system which can be oriented in any position and which provides an output signal when it is moved or tilted. The system includes an oscillator which provides an output signal; the amplitude of the oscillator signal is modulated responsive to motion. A signal level detector provides an output signal when the modulation amplitude exceeds a predetermined level. The output signal from the level detector indicates excessive motion and can be used to provide an alarm or to control associated equipment.

Abstract: A mounting structure for double-bar resonators to ensure symmetrical loading of the resonator responsive to external forces. In one embodiment, the resonator is connected to a pair of mounting pads through compliant coupling members. The coupling members allow longitudinal, force-induced displacements of the mounting pads to load the resonator while making the resonator insensitive to spurious transverse displacements of the mounting pads. In another embodiment, a force is applied to a load-sensitive, double-bar resonator through a force-transmitting bar which is mounted on an elongated flexure hinge. The hinge is compliant about an axis of rotation which is perpendicular to the longitudinal axis of the resonator so that the hinge attenuates any force component acting perpendicular to the longitudinal axis of the resonator which would otherwise non-symmetrically load the resonator.

Abstract: A flat measuring string is disclosed that is formed from a blank of sheet metal (such as a niobium-zirconium alloy), characterized by the provision of bendable or foldable wing flaps arranged at the nodal portions of the string, thereby to permit the connection of nodal masses to the string. In this manner, it is possible to achieve good measurement-technical data, especially, data regarding hysteresis and creepage under load, coupled with extensive freedom in the choice of materials and very economical mass production of the string components. The measuring string is particularly suitable for use in force or distance measurement.

Abstract: A vibratory, force transducer includes a pair of elongate, generally parallel bars coupled together at their ends in a type of double-ended tuning fork arrangement. The bars each have a thickness of t, a width of w and a length between fixed ends of L. The distance separating the points where the bars are coupled together is m. Apparatus is provided to cause the bars to vibrate in a transverse direction and in substantially 180.degree. phase opposition. Apparatus is also provided for determining the frequency of vibration of the bars so that when the bars are subjected to either compressive or tensile forces along the longitudinal axis of the bars, the magnitude of such forces can be readily determined by simply determining the magnitude of the frequency change. The values of w and t are selected so that 0.

Abstract: A rotation angle detecting device with a pair of variable capacitors which are formed with a rotating object, i.e. a movable electrode, and two stationary electrodes disposed around the rotating object, so that the capacitors operate in a differential mode. Alternatively, the central electrode can be stationary while the two outer electrodes move with the rotating object. The capacitors are combined with oscillators, so that a signal varying with the rotation of the rotating object is provided by obtaining the difference between the output frequencies of the oscillators.

Abstract: To increase the responsiveness of a vehicle alarm system to, for example, unauthorized entry through windows, jacking up for removal of parts or vehicle theft as well violent impact by another vehicle, at least one position sensitive sensor has its output signal, which represents the instantaneous position of the vehicle stored after activation of the alarm system. Any change in that position is detected and triggers a warning device when the deviation exceeds a predeterminable amount. The position sensitive sensor may be a fluid-filled vessel the internal resistance of which is measured in a resistance bridge or it may be a variable inductance sensor which is connected to a frequency generator whose output signals are counted and compared with a given value. The system according to the invention may also serve as an accelerometer.

Abstract: Instrument system including an electronic transmitter for a vibrating-wire differential-pressure sensor at a field location and connected by a two-wire line to a control room. The transmitter includes an oscillator to produce vibrations of the wire at its resonant frequency, and applies to the two-wire line a corresponding alternating voltage signal. The control room equipment converts this raw measurement data to an analog measurement signal. The control room equipment provides for adjustment of the zero and span of this signal, and for linearization with respect to the input differential pressure. The two-wire line carries a direct-current component the average value of which is automatically adjusted at the control room to match the scaled and linearized analog measurement signal. This line current passes through a meter at the transmitter to provide field service personnel with a visual indication of the value of the scaled and linearized measurement signal.

Abstract: The method of making a force-responsive instrument of the type including a tensioned wire of round cross-section to be vibrated perpendicular to the wire axis, wherein said instrument includes field-producing magnetic means operable with said wire to induce vibration; said method including the steps of:positioning said wire in a magnetic field directed perpendicularly to the wire axis;vibrating said wire by electrical means connected to the wire and arranged to develop interaction with said magnetic field;developing an electrical signal proportionately responsive to the magnitude of vibrations of said wire;effecting relative rotation between said wire axis and said magnetic field while maintaining constant the intensity of said magnetic field;making measurements of the amplitude of the signal developed by said wire;determining from said measurements the position of said wire relative to said magnetic field providing maximum signal amplitude; andfixing said wire in said instrument in said position relative to

Abstract: A force transducer is provided comprising a vibrator having a pair of plate-shaped vibrating pieces parallel with each other, coupling pieces for joining the respective ends of the vibrating pieces, and attachment portions connected to the coupling pieces, exciting means for causing the vibrator to resonate, and sensing means for detecting the vibrations of the vibrator. An input force to be converted is applied in the longitudinal direction of the vibrating pieces. This force transducer is capable of converting an industiral process variable such as force, pressure, difference pressure, weight or level into a proportional frequency signal at a high efficiency.

Abstract: Positive feedback is utilized with a flexible piezoelectric strip that is stretched in tension to cause the strip to oscillate at a frequency which is determined by the magnitude of the force stretching the flexible strip. Since the oscillation frequency can readily be measured, the strip is utilized as a device for measuring tension.

Abstract: A vibratory wire strain gage and more particularly a vibratory wire strain gage having an improved means for readily tensioning the gage wire and, if desired, adjusting such tension prior to installation.

Abstract: A mass and force meter locked over its measuring system and comprising a frame, a load support, and a force transmission channel with a load-dependent force transmission ratio and at least one swivel lever is provided, in which the combination of the non-linearity of the measuring system with that of other elements of the meter can be eliminated with a force transmission channel having a non-linear characteristic, such a channel having a smaller resilience than the known meters coupled with a better adaptability to meeting the requirements for the parameters determining the non-linearity to be eliminated and with easy adjustment of these parameters, the swivel lever being connected with at least one adjacent element of the force transmission channel by means of a link having one of its ends fitted to the swivel lever, the link being mounted at least partly outside the action line of the force transmitted and being at least zone-wise elastically bendable.

Abstract: A digital pressure sensor for measuring fluid pressures at relatively high temperatures includes an electrically conducting fiber coupled to the fluid by a force disc that causes tension in the fiber to be a function of fluid pressure. The tension causes changes in the mechanical resonant frequency of the fiber, which is caused to vibrate in a magnetic field to produce an electrical signal from a positive-feedback amplifier at the resonant frequency. A count of this frequency provides a measure of the fluid pressure.

Abstract: An acceleration sensor including a block having comb-like projections forming three cantilever beams. A semiconductor filament is then fixed in tension between each adjacent pair of the beams. The beam on one extreme side has a length equal to that of the beam on the other, whereas the center beam is longer than the other two.

Abstract: A mass and force meter comprising, a frame, a load support connected to said frame; a measuring system comprising two dynamometers, a reference base and a force input; a load spring mounted between said frame and said load support, and a measuring spring mounted between said load support and said force input, said load spring being at least ten times stronger than said measuring spring, said load spring and said measuring spring eliminating partly or completely force-reducing lever systems in mass meters and allowing, if required, the linearization of non-linear characteristics of several components of the meter.

Abstract: A minute change detecting system comprises sensor means which changes its electrical constant according to a physical change of an object under measurement to affect the oscillation frequency of at least one of two high-frequency oscillators, and mixer means for producing a beat frequency signal from the output oscillation frequencies of the two oscillators, thereby to detect the physical change.

Abstract: A pressure measuring instrument of the vibrating-wire type comprising an elongate base on which is pivotally mounted an elongate lever parallel to the base. A vibratory wire in the form of a very thin flat ribbon of tungsten is held tautly between the lever and the base. A pair of bellows are supported on the base, on opposite sides of the pivot mounting for the lever, and apply a torque to the lever proportional to differential pressure. Counterbalance means are provided to prevent errors with changes in spatial orientation of the instrument. The lever support-structure is formed of a composite of elements providing a match of temperature expansion characteristics with the vibratory wire. An overrange protection mechanism prevents the application of excessive force to the wire.

Abstract: A monitoring system for detecting and indicating typical operating conditions, particularly vibration of an aircraft engine, wherein at least two measuring feelers such as accelerometers are exposed to the same conditions, the output signals from said feeler are compared with each other and logical means detect normal conditions when the output signals are equal, system defect conditions when the output signals differ from each other and alarm conditions when the output signals both exceed a safety limit. Such a system greatly increases the reliability and at the same time avoids false alarms.

Abstract: A digital weigh feeder includes a conveyor belt for transporting material thereon. The conveyor belt has an average tare weight. A digital weight transmitter provides at least first and second outputs having first and second frequencies respectively. The ratio of the first and second frequencies is indicative of the weight of material on the belt. A weight processor digitally computes a scaled ratio of the first and second frequencies. An auto tare circuit digitally computes the average tare weight of the conveyor belt. The computed average tare weight is substracted from the computed scaled ratio of the first and second frequencies to obtain a reading of the actual weight of material on the belt.

Abstract: A tensioned helical wire for use as a displacement sensor. The sensor made of high strength piano wire is attached at its ends to two anchors which in turn are attached to or are a part of the object or objects to be tested. In the preferred embodiment the sensor has straight ends which are attached to two small anchor blocks. These blocks are then attached to the test object. The displacement range and sensitivity of the sensor can be controlled by the initial geometry selected. If an initial tension applied is small, the sensor has a very large response range that is about fifty times that of a straight wire sensor. If a large initial tension is applied, the helical shape approaches that of a straight sensor and has a displacement range only a few times that of a straight wire sensor. If the sensor has a large displacement range, the sensitivity is much less than that of a straight wire sensor and if the sensor has a small range the sensitivity is comparable to that of the straight wire sensor.

Abstract: A mass and force meter with a frame, a load-support and a measuring system, wherein the mass or force to be measured acts indirectly on the tension of two transversally vibrating, pre-loaded strings excited by electronic means, so that the resultant frequency changes serve for calculating the magnitude of said mass or force in a computing device. Both strings, a first transmission element for the transmission of a pre-loading force and a second transmission element for the transmission of a force depending on the load to be measured are fixed to a force distributor.

Abstract: A method and apparatus is provided for measuring tension in stressed cables in which use is made of the relationship between the tension and the natural frequency of vibration of the cable. An electrical signal is generated by sensing the fluctuating field of a small permanent magnet attached to the vibrating cable and generating from this signal a periodic pulse signal having an average level proportional to the square of the cable variation frequency. The resulting signal is scaled to produce a final signal which is directly proportional to cable tension.

Abstract: A temperature compensation mechanism for a vibrating beam accelerometer comprising first and second bridge circuits. A quadrature signal is applied to the first bridge circuit containing the quartz crystal which pulls the resonant frequency of the quartz oscillator up or down depending upon the frequency shift caused by temperature variations.

Abstract: A pressure measuring instrument of the vibrating-wire type comprising an elongate base on which is pivotally mounted an elongate lever parallel to the base. A vibratory wire in the form of a very thin flat ribbon of tungsten is held tautly between the lever and the base. A pair of bellows are supported on the base, on opposite sides of the pivot mounted for the lever, and apply a torque to the lever proportional to differential pressure. Counterbalance means are provided to prevent errors with changes in spatial orientation of the instrument. The lever support-structure is formed of a composite of elements providing a match of temperature expansion characteristics with the vibratory wire. An overrange protection mechanism prevents the application of excessive force to the wire.

Abstract: A primary sensing device, or apparatus, for measuring energy level changes, or variations, in a medium capable of transmitting energy. An elongated reed, the ends of which are tensioned upon suitable support means, is acted upon by the energy level changes, or variations, within the medium and energy is absorbed by the reed which causes the latter to resonate in a harmonic mode to produce nodes and antinodes in known relation to the amount of energy transmitted thereto by the medium and absorbed by said reed. An output signal, suitably as produced by one or a plurality of strain gauges, is taken off from the resonating reed, and interpreted via suitable read-out means as an intelligible signal indicative of the change in magnitude of the variable property measured within the medium.

Abstract: A force-measuring instrument of the vibrating-wire type wherein the mechanical components are located at the force-measuring location and the vibrating wire is coupled through a two-wire transmission line to electronic circuitry at a distant location. The electronic circuitry includes means to excite the vibrating wire and to produce a d-c measurement output signal corresponding to the frequency of vibrations. The electronic circuitry further includes function-generating means to establish a closely-linear relationship between the output current and the force applied to the wire. Means also are incorporated in the electronic circuitry for adjusting the zero and span of the instrument, and this can be done without interaction between the adjustments.

Abstract: A tension in a paper or foil web is measured by subjecting an area of the web between points of support to transverse oscillations. The impedance of an oscillation generating means located adjacent the web changes with the oscillation and impedance is measured with the transverse oscillation at a frequency approaching the expected fundamental resonant frequency for the web tension under consideration. The damping effect of the transverse oscillations by the web is a function of the web tension.

Abstract: A damping mechanism suitable for use with a vibrating beam accelerometer comprising a piezoelectric block mounted between the vibrating beam force transducer and the pendulum of the instrument. The proof mass, or pendulum, is mounted for pendulous motion about a pair of hinge means. Vibration of the instrument causes opposite charges to appear on electrodes which are on two opposite faces of the block. These charged electrodes are connected to each other by a resistor and so a current will flow through the resistance to neutralize the charge. The resistor will then dissipate the vibration energy as heat. This energy dissipation is effectively damping.

Abstract: Apparatus and methods for measuring strain and torque are described. The apparatus, which is used in the methods, usually includes a thin walled cylinder within a thick walled cylinder, the cylinders being fixed together at their ends only, means for vibrating the walls of the thin walled cylinder and means for indicating the frequency of vibration. As torque is applied to the thick walled cylinder and therefore to the thin walled cylinder, longitudinal strain appears in the thin walled cylinder and the frequency of vibration changes. Thus an indication is obtained of the applied torque or of strain in a test member applying the torque.

Abstract: A vibrating quartz accelerometer of moving object under test, wherein both ends of at least two vibrating quartz resonators are rigidly coupled each other so as to confront their faces each other and to form gap between said resonators, one end of which is made as a fixed end to said moving object and another end thereof is made as a free end to said moving object, a weight is provided on said free end, and when said moving object is put into motion, inertia force, which acts on said weight in the direction for keeping original state of motion or state of standstill relative to said motion, is converted into beat frequency in resonant frequency of said two vibrating quartz resonators, which beat frequency is caught to detect acceleration of said moving object.

Abstract: A mass and force meter comprising a frame, a load support, a digital evaluation and display device and two electrically-excited, transversely-vibrating, pre-tensioned strings each having one end fixed to the frame. The other ends of the strings are connected to a force distributor, and first and second transmission elements are provided for transmitting to the force distributor a pre-tensioning force and a force which depends on the load to be measured. One end of each of the transmission elements is fixed to the force distributor and the other ends are connected to the respective pre-tensioning and load forces. A guide member having one end connected to the frame and the other end connected to the force distributor acts together with the strings to guide the force distributor in a statically defined manner relative to the frame with respect to the pre-tensioning force and the force established by the load to be measured.

Abstract: A loaded spring in a pressure relief valve or other spring-loaded device is excited with acoustic vibrations and the resonant frequencies of selected vibration modes are measured. Changes in spring constant due to aging and high temperature are detected by monitoring the longitudinal vibration mode resonant frequency, and changes in loading by monitoring the transverse and/or torsional vibration mode resonant frequency. The pressure set point is ascertained from manufacturing data of resonant frequency versus set point.

Abstract: A force and mass meter using two transversally vibrating preloaded strings as the force sensitive members. The two strings are placed in a transverse magnetic field and are caused to vibrate by means of an exciting current flowing across them which is delivered by one exciter each. The exciters consist of a metering bridge, and an operational amplifier deriving the exciting current from the error signal measured across the bridge. Mutual interference of the two exciters is drastically reduced, when the point of common potential of the two exciters is connected with at least one conductor to each of the exciters.

Abstract: A vibratory-wire strain gage has mounting flanges integral to the instrument for disposition of the wire and its low-profile casing in intimate, substantially coplanar relation to the measuring surface.

Abstract: A vibrating wire measuring instrument, such as a vibrating wire galvanometer, dynamometer, or strain gauge, wherein the wire which is to execute transverse vibrations is mounted between two fixing members, and node masses are rigidly attached to the wire so that the latter is subdivided into (a) two connection portions (between the node masses and the fixing members) and (b) an intermediate portion (between the node masses); the wire is of constant cross section and integrally formed; the node mass may be soldered or welded to the wire or clamped, e.g. in a detachable manner.

Abstract: The proposed force measuring transducer with a frequency output signal comprises an elastic body arranged in a casing in spaced relationship with said casing. The elastic body, which is subjected to the action of a force, has a base and a working member. The base is secured in the casing with the aid of at least three supports. One end of each support is tapered and bears up against the surface of the base, whereas the other end of each support is joined to the casing. The working member is connected to an oscillating element whose oscillation frequency is dependent upon the action of the force. The oscillating member is the resonator of an electromechanical self-excited oscillator.

Abstract: Mass and force meter with a frame, a load-support and a measuring system, wherein the mass or force to be measured acts indirectly on the tension of two transversally vibrating, pre-loaded strings excited by electronic means, so that the resultant frequency changes serve for calculating the magnitude of said mass or force in a computing device, both strings, a first transmission element for the transmission of a pre-loading force and a second transmission element for the transmission of a force depending on the load to be measured being fixed to a force distributor guided in a statically determined way relatively to the frame by means of the two strings and of at least one guide with respect to the pre-loading force and to the force depending on the load to be measured. The force distributor comprises three parts forming a triangle, both strings, the guide and both transmission elements being fastened to the corners of the force distributor.

Abstract: A contactless inductance interface pickup, having within an external housing an auxiliary housing installed, and formed as a pot, with at least the bottom thereof being constructed from a non-magnetic material, and a clearance between the external housing and the auxiliary housing wherethrough a cooling agent flows around the pickup. Inside the auxiliary housing, in immediate proximity to the bottom thereof, a magnetic circuit is disposed with at least one measuring winding and at least one energized winding.

Abstract: A mass and force meter having a frame, a load support and a digital computing device, a first and a second electrically excited, transversely vibrating string, first transmission elements transmitting the mass or force to be measured to said strings, second transmission elements transmitting a pre-loading force to said strings, so that the resultant frequency variations caused by the application of said mass or force are used in the computing and display device for computation of the magnitude of said mass or force, said first transmission elements having a first and a second branch, a first guide fixed to the frame, said first string having one end fastened to said frame and the other end connected to one end of said second string, to said first guide and to said first branch of said first transmission elements, a second guide fixed to the frame, the other end of said second string being connected to said second guide, to said second transmission elements and to said second branch of said first transmission

Abstract: A force measuring apparatus having a vibrator which resonates with the frequency of a vibration generator. The force to be measured is applied directly to the vibrator in a manner to effectively tune it to the frequency of the generator. The vibrating motions of the vibrator are transmitted to a transducer which converts them to an electric signal which in turn is fed into a readout device.

Abstract: A force sensing device in which the oscillations of a vibrator are damped by applying a weight, force, which is to be measured directly against a vibrating element. The output of a transducer, which converts the vibrator's motions into an electric signal, is fed into a readout instrument, recorder, or computer for observation and evaluation.

Abstract: This invention discloses apparatus for linearizing the relation between altitude and an output signal of a sensor which represents the n th power of atmospheric pressure by means of generating a basically exponential signal of a parameter and obtaining the corresponding value of the parameter at which the exponential signal coincides with the output signal of the pressure sensor. This invention also includes means for measuring an accurate altitude by correcting the above linearized value according to the standard atmosphere adopted by the ICAO by means of generating a function for compensating the effect of temperature distribution of the standard atmosphere.

Abstract: A force-measuring instrument of the vibrating-wire type wherein the mechanical components are located at the force-measuring location and the vibrating wire is coupled through a two-wire transmission line to electronic circuitry at a distant location. The electronic circuitry includes means to excite the vibrating wire and to produce a d-c measurement output signal corresponding to the frequency of vibrations. The electronic circuitry further includes function-generating means to establish a closely-linear relationship between the output current and the force applied to the wire. Means also are incorporated in the electronic circuitry for adjusting the zero and span of the instrument, and this can be done without interaction between the adjustments.