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Showing papers on "Transducer published in 1972"


Patent
07 Jan 1972
TL;DR: In this paper, an ultrasonic motor construction where the compressional wave mechanical energy is transmitted through a transmission member into flexural vibrational wave energy to a working tip or surface removed a distance from the transducer associated therewith is described.
Abstract: An ultrasonic motor construction wherein the compressional wave mechanical energy is transmitted through a transmission member into flexural vibrational wave energy to a working tip or surface removed a distance from the transducer associated therewith. Various forms of ultrasonic motor constructions are illustrated as in the form of a welding instrument or scissor. The ultrasonic motor operates between 10,000 cps and 500,000 cps and produces peak accelerations of the order of the last 1,000g.

104 citations


Patent
18 Aug 1972
TL;DR: A piezoelectric-type electroacoustic transducer composed of two convex or concave polymers with electrodes on both surfaces of the polymers is described in this article.
Abstract: A piezoelectric-type electroacoustic transducer composed of two convex or concave piezoelectric polymer films each having electrodes on both surfaces thereof, said two polymer films being so connected to electric wiring that, when the one of the piezoelectric polymer films elongates by the action of an electric field in one direction, the other shrinks by the action of the same electric field.

72 citations


Patent
21 Apr 1972
TL;DR: In this paper, a conditioning circuit includes a computer connected to a pressure transducer having a variable frequency oscillator the output signal of which varies with pressure, a temperature sensor, a read only memory storing constants which are dependent upon the particular transducers and application, and a counter connected to count the variable frequency output signal when gated.
Abstract: A conditioning circuit includes a computer connected to a pressure transducer having a variable frequency oscillator the output signal of which varies with pressure, a temperature sensor, a read only memory storing constants which are dependent upon the particular transducer and application, and a counter connected to count the variable frequency output signal when gated. In accordance with the disclosed method, the computer obtains a digital count signal indicative of oscillator frequency by gating the output signal to the counter for a predetermined interval, converts an analog signal from the temperature sensor to a digital signal, and then computes a linearized, temperature compensated digital pressure signal in accordance with a predetermined function which utilizes constants stored in the read only memory to initially scale and translate the count signal for maximum computer accuracy, corrects for nonlinearities in the count signal, and corrects for variations in the count signal with temperature. The computed signal then appears at the output as a binary digital word accurately representing sensed pressure over a wide range.

71 citations


Journal ArticleDOI
TL;DR: Fluid-containing structures can be localized and aspirated by using a specially-designed ultrasonic transducer with a central hole and a needle is directed through the hole and into the tissue.
Abstract: Fluid-containing structures can be localized and aspirated by using a specially-designed ultrasonic transducer with a central hole. A needle is directed through the hole and into the tissue. The path of the needle tip can be followed ultrasonically as it enters the fluid. The same transducer is used to monitor the procedure continuously while the fluid is aspirated.

70 citations



Patent
24 Feb 1972
TL;DR: In this paper, an ultrasonic imaging scanner was proposed to produce a processed signal time function for high resolution imaging of reflecting bodies in a multiuser ultrasonic propagation medium, where a sequence of phase coherent ultrasonic pulse signals is produced from a set of transducer positions.
Abstract: This invention comprises an ultrasonic imaging scanner which produces a processed signal time function for high resolution imaging of reflecting bodies in an ultrasonic propagation medium. A sequence of phase coherent ultrasonic pulse signals is produced from a set of transducer positions. The reflected pulse signals are detected and mathematically processed with specified filter functions to produce a processed signal time function from which a high resolution image of the reflecting bodies can be produced.

67 citations


Patent
05 Jun 1972
TL;DR: In this paper, a bone conduction microphone assembly with a transducer mounted in a transducers mount supported from a surrounding support member by spring means is presented, which yieldably urges the transducers against the user''s head with predetermined pressure.
Abstract: A bone conduction microphone assembly with a transducer mounted in a transducer mount supported from a surrounding support member by spring means which yieldably urges the transducer mount against the user''s head with predetermined pressure.

65 citations


Journal ArticleDOI
TL;DR: In this article, a transducer for the generation of high directional ultrasonic radiation in fluids is studied, which consists of a plate of particular shape set in oscillation by an adequate vibrator.
Abstract: A transducer for the generation of high directional ultrasonic radiation in fluids is studied. It consists of a plate of particular shape set in oscillation by an adequate vibrator. Since the directional pattern depends substantially on the phase with which the single elements of the plate vibrate, the radiating surface is shaped into steps covering areas vibrating with the same phase, the height of the steps being equal to a half‐wavelength of the radiated sound, in order to obtain a coherent acoustic radiation. To facilitate the design of such plates, an approximate theory of their vibration is shown, and the experimental proofs, whose results confirm the full validity of the adopted method, are described.

64 citations


Patent
06 Mar 1972
TL;DR: A vortex-type mass flowmeter for measuring the mass of fluid passing through a flow tube as well as the density thereof is described in this article, where a pressure responsive transducer adapted to generate an electrical signal whose frequency is proportional to the fluidic pulse rate and whose amplitude is a function of the kinetic energy contained in the vortex.
Abstract: A vortex-type mass flowmeter for measuring the mass of fluid passing through a flow tube as well as the density thereof. A bluff body, swirl blades or other means disposed within the tube acts to create a pulsatory fluidic vortex therein whose frequency varies as a function of the volumetric flow rate of the fluid being measured. Placed within the flow tube is a pressureresponsive transducer adapted to generate an electrical signal whose frequency is proportional to the fluidic pulse rate and whose amplitude is a function of the kinetic energy contained in the vortex. The transducer signal is processed by an operational amplifier, the gain of which is inversely proportional to frequency, thereby effectively dividing the transducer signal by frequency throuhgout the operating range of the meter to yield an output signal whose amplitude is indicative of mass flow. By additionally dividing this output signal by frequency with a second amplifier having a gain which is inversely proportional to frequency, a signal indicative of the fluid density is produced.

59 citations


Patent
Donald K. Georgi1
22 May 1972
TL;DR: In this article, an optical sensor is used to translate the movement of a positive displacement pump into electrical signal pulses that are serially fed into a counter which converts them to parallel binary or binary-coded decimal form.
Abstract: An apparatus and method for a fluid metering system that employs a high resolution position sensor and electronics to very accurately control the amount of fluid dispensed. This sensor may be an optical sensor which translates the movement of a positive displacement pump into electrical signal pulses that are serially fed into a counter which converts them to parallel binary or binary-coded decimal form. The optical sensor uses a lightsensitive transducer to convert light rays to electrical pulses, a light source, and two graticule frames therebetween. One graticule frame moves relative to the other graticule. Each of the graticules has a large number of equally-spaced lighttransmitting areas. Preset counts in the counter compensate for time lags in the system operation such as the lag due to the movement of the dispensing valve and the solenoid valve in an actuating piston. These preset counts are added to the serial counts from the sensor, and then an electrical signal from the counter is sent to a comparator which compares the sum with a programmable number. This programmable number directly relates to the amount of fluid it is desired to dispense. When it and the sum from the counter are equal, the comparator sends a second signal to actuate the solenoid valve which results in the fluid flow being stopped. The programmable number may be manually inputted or may be determined by any measurable characteristic of an object, like its weight, or any fixed relationship relating to the object, for example, a percentage of its weight. In a modification to the basic system, provision is also made to control the position of the object fluid is being dispensed into relative to the dispenser. Positioning is obtained by utilizing a control circuit and an hydraulic-linear actuator to move the object. This latter operation may be positionally controlled by a signal directly proportional to the object''s weight, for example, the weight of a fowl that is being injected with a fluid additive.

57 citations


Journal ArticleDOI
TL;DR: In this paper, a novel dispersive delay line with a time-bandwidth product in excess of 1500 has been developed, which uses the reflection of elastic surface waves from sputter-etched gratings on LiNbO3.
Abstract: A novel dispersive delay line with a time-bandwidth product in excess of 1500 has been developed. The device uses the reflection of elastic surface waves from sputter-etched gratings on LiNbO3. This reflective-array compressor is relatively free of the spurious signals which limit the performance of inter-digital transducer arrays.

Patent
22 Dec 1972
TL;DR: In this article, an information storage system is disclosed in which a reticle and associated photocell are used to effect coarse positioning of a transducer relative to a desired informational track, following which a fine system is used for track accessing and following.
Abstract: An information storage system is disclosed in which a reticle and associated photocell are used to effect coarse positioning of a transducer relative to a desired informational track, following which a fine system is used for track accessing and following. The transducer senses both information and servo data which are serially disposed on a storage medium such as a magnetic disc, the servo data comprising groups of magnetized pattern areas corresponding to groups of concentric tracks. The pattern areas have staggered flux reversals providing relative track indentification for each group of tracks. A digital address defining the location of a desired track within a group of tracks is decoded so as to generate a window signal determining the polarity of errors in the position of the transducer. The polarities of the sensed flux reversals are coded in time under the control of the window signal so as to provide an error signal which communicates with an actuator to move the transducer toward the desired track and into precision alignment therewith.

Patent
10 Oct 1972
TL;DR: In this paper, a measuring apparatus for detecting relative movement between a fixed object and a movable object is disclosed. The measuring apparatus comprises a transducer guided on a grating tape slidingable mounted within a housing.
Abstract: A measuring apparatus for detecting relative movement between a fixed object and a movable object is disclosed. The measuring apparatus comprises a transducer guided on a grating tape slidably mounted within a housing. The housing is connected to one of the relatively moving members. The transducer is connected to the other of the relatively moving members. A flexible ball joint provides the connection between the transducer and the other relatively moving member. Means are provided for length calibration and to compensate for expansion and contraction due to temperature fluctuations. The whole measuring system is self-contained so that the system accuracy is not dependent on relative accuracies of the carrier machine members.

Patent
G Brock1, F Schelledy1
11 Oct 1972
TL;DR: In this article, the need for accurate and stable bias to reduce distortion is eliminated by subjecting similar adjacent MR elements to opposite currents, and each element is then symmetrically and oppositely biased so that a differential resistance sensing circuit provides an output signal relatively immune to distortion.
Abstract: A magnetic transducer exhibiting the magnetoresistive (MR) effect includes at least two thin film layers. A three-legged MR film in electrical contact with a higher resistivity layer is magnetically biased by a portion of the MR sense current shunted through the nonmagnetic layer. The need for an accurate and stable bias to reduce distortion is eliminated by subjecting similar adjacent MR elements to opposite currents. Each element is then symmetrically and oppositely biased so that a differential resistance sensing circuit provides an output signal relatively immune to distortion.

Patent
16 Nov 1972
TL;DR: In this article, an ultrasonic transducer is described having an alternating current conductor located in the field of a permanent magnet with said conductor defining a serpentine path lying parallel to the surface of a test object to induce eddy currents in the test object flowing in directions transverse to the magnetic field of the permanent magnet.
Abstract: An ultrasonic transducer is disclosed having an alternating current conductor located in the field of a permanent magnet with said conductor defining a serpentine path lying parallel to the surface of a test object to induce eddy currents in the test object flowing in directions transverse to the field of the permanent magnet. Two such transducers are provided and are employed as a transmitter-receiver pair to generate and detect Rayleigh, Lamb, or other elastic waves within the object under test without requiring contact of the transducers with the object.

Patent
Keisuke Honda1
08 May 1972
TL;DR: In this paper, an ultrasonic cleaning device is provided which comprises a base unit and a cleaning chamber unit removably mounted on the base unit, and the high frequency energy output of a high frequency oscillator circuit which is disposed within the base units together with a power supply circuit is transmitted to the ultrasonic frequency transducer by electromagnetic induction coupling.
Abstract: An ultrasonic cleaning device is provided which comprises a base unit and a cleaning chamber unit removably mounted on the base unit. An ultrasonic frequency transducer is attached to the bottom of a cleaning chamber, and the high frequency energy output of a high frequency oscillator circuit which is disposed within the base unit together with a power supply circuit is transmitted to the ultrasonic frequency transducer by electromagnetic induction coupling.

Patent
02 Mar 1972
TL;DR: In this article, a transducer of a size and nature adapted to be held in the mouth for producing ultrasonic (or subsonic) vibrations in the closed liquid was presented.
Abstract: Apparatus for cleaning teeth with liquid dentifrice, optionally mixed with dental-disease-inhibiting agents, comprising: a transducer of a size and nature adapted to be held in the mouth for producing ultrasonic (or subsonic) vibrations in the mouthinclosed liquid; a handle attached to the transducer; a circuit leading to the transducer, including an electric oscillator, an optional automatic time control, a switch actuator (optionally a pushbutton), and an electric cord that goes thru the handle. The portion of the transducer assembly that fits between the lips is sufficiently small in vertical thickness to allow the lips to seal around this portion against escape of the dental solution. The invention includes a simple and efficient method of cleaning teeth comprising filling the mouth with liquid dentifrice and sonically (ultrasonically or subsonically) agitating and circulating the liquid into all areas of the mouth.

Patent
24 Jan 1972
TL;DR: In this article, the thickness of one or several superimposed sheets is sensed to determine how many sheets are simultaneously transported, and the transformed signals are evaluated and supplied by an output selector to different outputs which are, respectively, correlated with different numbers of sensed sheets.
Abstract: An apparatus and a method for controlling the correct transport of sheets. The thickness of one or several superimposed sheets is sensed to determine how many sheets are simultaneously transported. Transducer means transform mechanical magnitude signals into signals having a different physical quality, for example electric signals, and the transformed signals are evaluated and supplied by an output selector to different outputs which are, respectively, correlated with different numbers of sensed superimposed sheets.

Journal ArticleDOI
T.R. Meeker1
TL;DR: In this paper, a tutorial review of the theory of the simple thickness mode piezoelectric transducer is given, showing what basic assumptions are made, and which material constants must be used in the equations.

Patent
01 Dec 1972
TL;DR: In this paper, a transducer is used to detect defects in rotating and/or reciprocating components, such as gears or bearings, and a demodulator converts the resulting signal into a series of pulses in which each pulse represents an individual impact.
Abstract: An apparatus for detecting defects or flaws in mechanical systems with rotating and/or reciprocating components, such as gears or bearings. The scheme utilizes a transducer, which is excited at its mounted natural frequency by the vibrations caused by the impacting of components of a device across a flaw in a bearing or the like, a filter to eliminate background noise and signals other than the natural resonant frequency of the transducer, and a demodulator which converts the resulting signal into a series of pulses in which each pulse represents an individual impact. A spectral analysis is then performed on the series of pulses to obtain the location and nature of the surface defect in the bearing or other rotating and/or reciprocating component.

Patent
12 Oct 1972
TL;DR: In this paper, a system for detecting the presence of particulate material, e.g., sand, in a fluid stream flowing through a conduit, is presented, which consists of an acoustical probe which is positioned directly into the flow stream.
Abstract: A system for detecting the presence of particulate material, e.g., sand, in a fluid stream flowing through a conduit, said system comprising an acoustical probe which is positioned directly into the flow stream. The probe has a housing in which a transducer, e.g., piezolectric crystal, is suspended. The housing is filled with oil to acoustically couple the transducer to the housing. Particulate material in the flow stream gives up kinetic energy upon striking the housing of the probe which in turn excites the transducer to generate an output signal having a frequency component which is representative of the particulate material. The system includes circuitry which amplifies and filters the output signal to provide a processed signal corresponding to said frequency component and which includes means for utilizing said processed signal, e.g., an alarm activated when a certain sand content condition in the flow stream is exceeded.

Journal ArticleDOI
TL;DR: An instrument for monitoring backscattered light from living tissue, in two wavelengths, is described, used for thein vivo determination of the blood's relative oxygen saturation and the intention of developing an optimal compact analogue processor.
Abstract: An instrument for monitoring backscattered light from living tissue, in two wavelengths, is described. The backscattered light data is used for thein vivo determination of the blood's relative oxygen saturation. The instrument contains a small optical transducer, 0·75 in. (19 mm) in diameter, with red and infra-red light emitting diodes (L.E.D.'s) and a photodetector. This small and easy to apply transducer allows monitoring the reflectance in various locations on the body. The light emitting diodes are controlled by a line synchronized pulse generator which alternatively drives the L.E.D.'s. The detection is accomplished synchronously and the photodetector's output is separated into red and infra-red channels, by means of a chopper and hold cicuits. This information is currently processed by a computer, with the intention of developing an optimal compact analogue processor.

Patent
06 Nov 1972
TL;DR: In this paper, a piezoelectric type electroacoustic transducer element having a high sensitivity in a high frequency region is composed of a PEG polymer sheet having on one surface thereof a backing of a material having a larger elasticity (Young''s Modulus) and mass than the elasticity and mass of the PEG sheet.
Abstract: A piezoelectric type electroacoustic transducer element having a high sensitivity in a high frequency region is composed of a piezoelectric polymer sheet having on one surface thereof a backing of a material having a larger elasticity (Young''s Modulus) and mass than the elasticity and mass of the piezoelectric polymer sheet.

Patent
02 Oct 1972
TL;DR: An electro-mechanical force sensing transducer for use with suitable receiving and recording means for measuring intraarterial blood pressure which includes a housing having a bore formed therethrough with a force sensing head disposed in the lower portion of the bore for engaging the surface of the skin over a superficial artery to sense blood pressure variations is presented in this article.
Abstract: An electro-mechanical force sensing transducer for use with suitable receiving and recording means for measuring intraarterial blood pressure which includes a housing having a bore formed therethrough with a force sensing head disposed in the lower portion of the bore for engaging the surface of the skin over a superficial artery to sense blood pressure variations. A positioning member is threadedly secured in the upper portion of the bore and a compression spring is disposed between the positioning member and the force sensing head for urging the force sensing head into contact with the surface of the skin. The force sensing head includes a conventional strain gage enclosed therein with electrical conduit means extending therefrom for connection to the receiving and recording means. Another aspect of the present invention is a transducer assembly including the force sensing transducer carried in a supporting frame and attachable to a patient by means of a strap secured to the supporting frame. In another form the transducer assembly includes two force sensing transducers. In still another form the force sensing transducer assembly includes three force sensing transducers. In yet another form the transducer assembly includes four force sensing transducers. Also disclosed are methods for continuously monitoring blood pressure utilizing the transducer assemblies disclosed.

Patent
10 Mar 1972
TL;DR: In this paper, a fluid flow metering method and system using digital signals and logic for producing a compensated manifestation of fluid flow by the mathematical multiplication of two or more sensed parameters, one parameter being the fluid flow rate and the other one or more parameters being related to a condition of the fluid such as its constituency, pressure, density, dielectric constant, temperature or the like.
Abstract: A fluid flow metering method and system using digital signals and logic for producing a compensated manifestation of fluid flow by the mathematical multiplication of two or more sensed parameters, one parameter being a fluid flow rate and the other one or more parameters being related to a condition of the fluid such as its constituency, pressure, density, dielectric constant, temperature or the like, where the parameters are represented by series of electrical pulses The digital output signal pulses of the flowmeter are related to fluid flow, and are used to gate packets of high frequency pulses from a transducer The duration of the pulse packet is designed to be less than spacing between two adjacent flow pulses at maximum flow rate, and the exact number of high frequency pulses in each packet is related to the condition of the fluid as sensed by the transducer In one embodiment, the duration of the packet is a function of time in which case the pulses in the packet may be gated from a continuous series of high frequency pulses having a frequency related to the condition of the fluid The flow pulses recorded in a first counter provide a manifestation of gross fluid flow The pulses from the packets recorded in a second counter provide manifestation of compensated fluid flow Subtraction of the pulse trains through suitable scalers can yield a manifestation directly related to the compensated fluid flow in the same units as are used in providing gross fluid flow A transducer output linearizing circuit and a flowmeter bearing friction compensating circuit may optionally be incorporated in the described system

Patent
20 Jul 1972
TL;DR: In this paper, motion within a large specified volume is detected by multiple ultrasonic transducer assemblies with a redundant microwave antenna to reduce false alarms, when either transducers indicate a fault condition, an alarm signal is generated by combining logic networks.
Abstract: Motion within a large specified volume is detected by multiple ultrasonic transducer assemblies with a redundant microwave antenna to reduce false alarms. Each of the ultrasonic transducer assemblies contains a plurality of highly directive transmitting radiating elements and/or a plurality of highly directive receiving elements. Combining networks interconnect the various radiating elements in parallel to a frequency source. The microwave transducer includes a transmit/receive antenna coupled to a microstrip oscillator through a microstrip balanced mixer. Signals from the ultrasonic transducers are processed by means of time integration to provide an alarm signal. Similarly, signals received at the microwave antenna are processed by means of time integration to provide an alarm signal. Alarm signals from both the ultrasonic subsystem and the microwave subsystem are combined in logic that responds to generate a system alarm only upon the simultaneous existence of alarm signals from both sources. Also coupled to the ultrasonic subsystem and the microwave subsystem is an automatic self-testing and tamper determining system. When either transducer source indicates a fault condition, an alarm signal is generated by combining logic networks.

Patent
13 Dec 1972
TL;DR: In this paper, an elongate bipartite housing constructed to be inserted into the auditory or hearing channel is provided, where in the lengthwise direction of the housing there are arranged adjacent to one another the output transducer, the voltage source, the amplifier, the input transducers and the gain control.
Abstract: A hearing apparatus equipped with an output transducer, a voltage source, an amplifier, an input transducer capable of magnetic or electrical reception and a gain control. There is provided an elongate bipartite housing constructed to be inserted into the auditory or hearing channel. In the lengthwise direction of the housing there are arranged adjacent to one another the output transducer, the voltage source, the amplifier, the input transducer and the gain control. The output transducer is arranged in a first part of the housing, the amplifier, the input transducer and the gain control are arranged in a second part of the housing which is detachably connected with the first part of the housing. The voltage source is arranged between the output transducer and the amplifier at the region of the connection location of the housing parts.

Patent
06 Nov 1972
TL;DR: An electrostatic type electroacoustic transducer having improved acoustic characteristics is composed of a piezoelectric polymer-type oscillator having a stretching-type PPE effect, such as a polarized polyvinylidene fluoride film having electrodes vacuum-coated on both surfaces and at least one fixed electrode disposed facing the oscillator and spaced therefrom.
Abstract: An electrostatic type electroacoustic transducer having improved acoustic characteristics is composed of a piezoelectric polymer-type oscillator having a stretching-type piezoelectric effect, such as a polarized polyvinylidene fluoride film having electrodes vacuum-coated on both surfaces and at least one fixed electrode disposed facing the oscillator and spaced therefrom.

Patent
07 Sep 1972
TL;DR: In this article, a hearing aid employs a differential transducer for converting sound information into an electrical output and to which sound energy can be directed in one of two modes: omnidirectional or directional reception.
Abstract: A hearing aid in which the sound reception characteristics are selectable by a user to provide omnidirectional or directional reception, as desired. The hearing aid employs a differential transducer for converting sound information into an electrical output and to which sound energy can be directed in one of two modes. In one mode of operation, for providing omnidirectional reception, sound is received from a front and rear aperture of the hearing aid and directed to a first input of the transducer. In a second mode of operation, for providing directional reception, sound energy received by the front facing aperture of the hearing aid is directed to the first input of the transducer, while energy received by the rearwardly facing aperture is directed to a second input of the transducer to substantially minimize the magnitude of sounds received from rearward positions.

Patent
04 Dec 1972
TL;DR: In this article, an underwater transducer with both projector and hydrophone elements was proposed, which allows the annular projector rings of a given piezoelectric material and resonant frequency to be tailored in diameter to accommodate various requirements such as a need for more interior space.
Abstract: An underwater transducer having both projector and hydrophone elements utilizes a new technique permitting the annular projector rings of a given piezoelectric material and resonant frequency to be tailored in diameter to accommodate various requirements, such as a need for more interior space. Where the projector rings can be expanded to the diameter of an accompanying hydrophone array, this makes possible a more compact and, in particular, a shorter structure than has been used for transducers of similar capability before. In the transducer the projector rings are positioned axially along a central support tube alternating with the hydrophones arranged in annular groups. Each projector ring is formed of a plurality of segments of alternately active material and inactive material having a sound velocity differing from (usually faster than) that of the active material. Thus the diameter of the annular elements for a given active material and a desired resonant frequency may be varied since the resonant frequency is related to the velocity of sound in the composite material used in the elements.