Abstract: A guided wave probe for use in guided wave testing of plate structures. The probe comprises a cup having a flat or nearly flat bottom, and a guided wave sensor, such as a magnetostrictive sensor, placed in the bottom of the cup. The sensor and/or cup are coupled to the plate structure, such that ultrasonic energy from the sensor is transmitted to the cup and the plate surface. The sensor is incrementally rotated in the cup, and sensor data is acquired at each incremental position.

Abstract: The present disclosure relates to a leak detection system and method for tube or catheter placement. The system and method includes acoustically sensing a leak in the seal between a tube or catheter within a body and the body cavity against which it is sealed, assisting the user in adjusting the system until the leak has been substantially sealed, and establishing system parameters to be used thereafter to maintain the system in an operating state that will substantially prevent leakage, all using a noninvasive acoustic technique.

Abstract: A breathing assistance system having active noise control may include a gas delivery system, a patient interface, a connection system, and a noise control system. The gas delivery system may supply breathing gas to a patient via the connection system and the patient interface. The noise control system may include a processor, a speaker, a reference signal source, and a feedback sensor. The processor may generate noise control signals to be output by the speaker for canceling noise caused by a noise source of the breathing assistance system. The reference signal source may communicate reference signals associated with the noise source. The feedback sensor may detect noise caused by the noise source and noise control signals output by the speaker, and communicate to the processor feedback noise signals based on the detected noise. The processor may generate the noise control signals based at least on the reference signals and the feedback noise signals.

Abstract: An apparatus for making pulsed acoustic measurements to determine particle size in a sample (1) such as a colloid. The apparatus includes two electrodes (2) between which an electric voltage is applied to the sample. The voltage is applied in short pulses. The applied voltage generates an acoustic signal, such as a sound wave (5), in the sample which is detected with a transducer (3) after the wave (5) has passed through a delay element (4). The delay element (4) is used to introduce enough of a time delay between the application of the voltage pulse and sound wave (5) reaching the transducer so that the received wave's signal can be isolated from any signal generated in the transducer (3) by the applied voltage. The delay element (4) and the transducer (3) are arranged into a geometry, or, alternatively, the delay element (4) is shaped, so that any reflections of the sound wave (5) from the sidewalls of the delay element (4) are deflected away from the transducer (3).

Abstract: The apparatus and method for moving a sensor over a workpiece includes a sensor, and an actuating member. The sensor, such as a non-destructive test sensor, is carried by the actuating member, and the actuating member is at least partially disposed within a housing. The actuating member is adapted for automated movement in one direction, and the housing may be configured to be grasped by an operator and manually moved in another direction. As such, the sensor may automatically move in one direction with respect to the workpiece without manual intervention, and manually move in another direction, such that the sensor is moved by the combination of automated and manual movement. In addition, the actuating member may have at least two substantially parallel arms extending from near the sensor, which permits the sensor to slide along the workpiece while maintaining a substantially normal relationship to a surface of the workpiece.

Abstract: An apparatus for making pulsed acoustic measurements to determine particle size in a sample (1) such as a colloid. The apparatus includes two elctrodes (2) between which an electric voltage is applied to the sample. The voltage is applied in short pulses. The applied voltage generates an acoustic signal, such as a sound wave (5), in the sample which is detected with a transducer (3) after the wave (5) has passed through a delay element (4). The delay element (4) is used to introduce enough of a time delay between the application of the voltage pulse and sound wave (5) reaching the transducer so that the received wave's signal can be isolated from any signal generated in the transducer (3) by the applied voltage. The delay element (4) and the transducer (3) are arranged into a geometry, or, alternatively, the delay element (4) is shaped, so that any reflections of the sound wave (5) from the sidewalls of the delay element (4) are deflected away from the transducer (3).

Abstract: In an ultrasonic inspection and imaging instrument, a pulse generator and a burst wave generator are provided in association with the activation of an ultrasonic probe by the pulse generator and in response to a measurement value obtained from a signal reception circuit portion. A first gate position is obtained with regard to an inspection portion in a sample, and then a second gate position for a burst wave measurement is set by correcting the first gate position. The burst wave measurement is performed by activating the burst wave generator.

Abstract: Ultrasonic wave converged by an acoustic lens is made incident onto a sample and wave reflected from the sample is received and converted into received electric signal by a transducer. A part of this electric signal is picked up by a gate section and the signal thus picked up is applied to an attenuator where it is converted into a variable ratio of input to output. The strength of the signal thus gain-adjusted is compared with a threshold value by a comparator. Responsive to the comparison result thus obtained, the gain of the attenuator is adjusted to make the input/output ratio of the attenuator a desired value. A computer calculates the focus position of the acoustic lens from a gain curve of the attenuator changing when the acoustic lens is moved from a position, remote enough from its focus position, to the sample. Drivel signal responsive to the result thus calculated is applied to a Z-drive control section.

Abstract: A measuring apparatus using an ultrasonic wave according to the invention transmits an ultrasonic wave pulse into a specimen, receives the echo reflected by the specimen and converts it into an electric signal. The components of the electric signal that represent the wave reflected by the specimen and contain data on the state of the specimen are extracted by a gate circuit. The components obtained by the gate circuit are converted into a power spectrum by a circuit for performing a Fourier transformation. The thickness of the specimen and/or the flaking state of the specimen can be determined from this power spectrum.

Abstract: An ultrasonic system for determining the quality of concrete under water hout inaccuracies caused by electromagnetic interference from the ultrasonic generator. An ultrasonic generator applies pulses to the concrete. An ultrasonic detector detects the ultrasonic pulses and produces corresponding signals that are indicative of ultrasonic pulses that have passed through the material. Signal processing circuitry processes the signals to determine the transit time of the ultrasonic pulses through the material. The signal processing circuitry is disabled for a predetermined time after application of each ultrasonic pulse to the material to prevent noise produced by the means for applying ultrasonic pulses to the material from entering the signal processing circuitry and causing spurious measurements.

Abstract: The binder content of bituminous building materials, especially asphalts is determined. To enable samples of relatively great mass to be analyzed within comparatively little time, the binder is removed from the sample by thermal degradation. The binder content is then calculated from the weight loss which the sample undergoes due to the thermal decomposition.

Abstract: A sample of a fuel/oil/additive mixture is metered continuously to a channel-like, inclined test element along which there is an increasing temperature profile. Under the increasing action of heat on the flowing mixture, solid residual products form on the test element after a certain flow distance. Their weight and the flow distance are evaluated in order to evaluate the additive.

Abstract: This system measures the concentration level of additives dissolved or sunded in a liquid by measuring the changes which the additives cause to the heat transfer characterisitics of the liquid. A plurality of cylinders and pistons sample the liquid to be measured and pump the samples past a hot film anemometer probe at a constant flow rate. A grid of wires upstream from the hot film anemometer probe is used to cause isotropic turbulence in the liquid flow around the measuring probe. The output signal from the measuring probe is proportional to the rate at which heat is transferred away from the probe by the liquid flowing past. The rate at which heat is transferred away from the probe is a function of the specific heat, thermal conductivity, viscosity, and turbulent flow characteristics of the liquid which in turn are a function of the concentration level of additives in the liquid.

Abstract: A sample cell connected through valving to a refrigeration system allows a prescribed mass of refrigerant with entrained oil to be collected and the refrigerant to be vaporized and returned to the system while leaving the oil in a graduated measuring tube. The sample cell has transparent upper and lower portions with graduated bores for measurement of the original sample and the oil residue, and an aluminum middle portion also containing a bore for conducting heat from the ambient air to the refrigerant to assist in the vaporization as well as for normalizing the temperature of the sample during filling.

Abstract: An impurity detector atomizes a liquid sample by injecting the sample into a chamber with a gas. In the chamber the liquid is heated, preferably by heating the gas prior to injection, to cause all the liquid to evaporate. The solid impurities contained in the liquid are thus entrained in the gas and carried to a detector region. The chamber is arranged so that all the gas and all the particles arrive at the detector region. A particle detector measures the number and size of the particles and from that measurement, the concentration of impurities in the sample can be determined. The system permits on-line operation, and produces accurate results.

Abstract: A cell (4) for analyzing a fluid which is condensable, at least in part. The cell comprises a volume (16, 17, 18) in which the fluid is inserted. The volume is delimited firstly by an envelope (11, 12, 13) and secondly by an upper piston (14) capable of sliding in a sealed manner in the envelope and associated with apparatus for adjusting the pressure of the fluid being analyzed, together with lower apparatus enabling the level of the gas/liquid separation surface to be adjusted. The envelope is provided with portholes (19) associated with marking in order to display and measure the level of the surface. Conduits (20, 21) are provided between the piston and said lower apparatus for inserting the fluid to be analyzed into the volume and for emptying the volume of the fluid. The cell includes the improvement whereby a rod (27) from a first hydraulic control actuator is linked to the upper piston and a lower piston (15) is connected to a rod (29) from a second hydraulic control actuator.

Abstract: A system and method for monitoring vibrations of a machine tool metal-cutting tool insert and interpreting them to promptly detect the initial touch to the workpiece and signal the tool to stop advancing before marring the surface. The signal generated by a sensor such as an accelerometer is preprocessed to eliminate lower frequency machine noise and detect the energy in a higher frequency band, then sampled and analyzed by digital circuitry. In order to avoid false alarms on high amplitude spiky noise pulses generated by traverse operation of the machine tool, the tool touch alarm is delayed longer than the maximum duration of the noise pulses. Two techniques are given to ignore the noise spikes while still detecting the tool touch signal.

Abstract: During a process for determining the percentage of a given liquid contained in a liquid mixture, the given liquid having a lower evaporation temperature than the rest of the mixture, an observed spontaneous change in an electric resistance wire, which is immersible into the liquid mixture, while temporarily applying a predetermined energy quantity and thus heating the wire until the liquid mixture reaches or exceeds boiling temperature, is used for determining suitable measured quantities. When supplying a specific and defined energy quantity, having been determined in a representative sample, for heating the wire to the boiling point of the liquid mixture, either the energy conversion, which occurred during this time interval with a constant time interval for the energy supply, or the time interval for the energy conversion, which occurred with a given energy quantity, is measured and compared with the corresponding measured quantities determined in the sample.

Abstract: The invention relates to a method of suppressing unwanted indications in automated ultrasonic testing of a test piece.In order to improve the suppression of unwanted indications, in particular in the case of extended statistical suppression, a variable discriminator threshold (3) is derived from the highest of all maximum amplitudes (2) by means of a predetermined amplitude difference (4), wherein the ultrasonic signals are not evaluated as flaw signals when only said variable discriminator threshold (3) is exceeded but are evaluated as flaw signals only when additionally at least the highest of all maximum amplitudes (2) exceeds the fixed discriminator threshold (1) preset for the testing operation.

Abstract: A semi-quantitative method for determining the amount of water in contaminated oil samples wherein a small sample of contaminated oil is placed in one or more compartments of a container. An equal size sample of reference oil of the same composition as the test oil, but containing a known quantity of water, is placed in one or more compartments of said container. The container is then heated rapidly and bubbles formed in the contaminated oil are compared with bubbles formed in the reference oil, thereby bracketing the water content rapidly (less than 5 minutes) with reasonable accuracy.

Abstract: A microprocessor controlled distillation analyzer for petroleum products performs, computes, displays and records distillation data. An interactive/keyboard display and printer system reports and records test conditions and prompts user inputs to define test parameters. Before the initial boiling point, the heater is automatically controlled in two time intervals. Following the initial boiling point, the heater is controlled to keep the monitored distillation rate within a predetermined range. Upon attaining an automatically calculated volume of distillate, the final heat is incremented to a programmed level. In one mode, the end point is automatically detected by monitoring vapor temperature for a decline, followed by the cessation of meniscus movement to terminate the test. After measuring the residue, the analyzer automatically recomputes temperatures at a series of percentage volumes of evaporated sample.

Abstract: A device for the detection of soot content of an oil sample is provided comprising a source of infrared radiation, an oil-sample receptacle of infrared permeable material, an infrared detector and an independent power means.

Abstract: In order to determine the boiling point of a liquid, especially a nonaqueous one such as a brake fluid, a device suspended in a body of that liquid--e.g. in a reservoir supplying fluid to a brake cylinder--forms a narrow chamber which is open at the bottom and the top and which contains means for heating the liquid in that chamber and measuring its temperature; the two functions can be simultaneously performed by a thermistor. When the boiling point is reached and the liquid in the chamber is vaporized, partial evaporation of that liquid and replacement thereof by fresh liquid from the main body results in a leveling of the temperature curve; the boiling point marked by this event can be read on a meter and/or qualitatively indicated by differently colored lights, for example. An excessive temperature rise early in the test will also show an unduly low liquid level in the reservoir.

Abstract: An object displacement sensor specifically adapted for high speed counting of passing nonmagnetic objects is disclosed which has a resonant circuit made up of at least one inductive element 2 and a condensor whose one plate consists of a conductive surface 3 and whose other plate is successively formed by each object 4 passing close to this surface 3. The resonant circuit is connected to a first oscillator 6 which determines the functioning frequency such that the signal issued from the first oscillator 6 is modulated in frequency to the rhythm of the passage of the objects 4.

Abstract: A method and a device for measuring the maturity of concrete, in which the heat generated by the setting of the concrete causes a special liquid to evaporate and the amount of evaporated liquid is taken as a measure of the concrete maturity. The liquid is contained in a closed capillary tube placed on a scale. For measuring purposes the capillary tube is broken at a well-defined point, and capillary and scale are then placed in a casing containing an absorbing agent for the evaporated liquid. The casing is hermetically sealed and pressed into the concrete. For reading purposes the casing is opened and the scale with the capillary is removed to determine the level of the liquid column and thus the maturity of the concrete.

Abstract: An apparatus for measuring acoustic emission is activated only at critical periods which are determined by detection of the background noise from a reference level. An acoustic emission transducer continuously transmits a signal to a detection circuit which delivers the top modulation envelope of the background noise to a comparator at a reference level delivered by a control unit.When a mean level of the background noise does not exceed a threshold reference level the AE is sampled at a low rate, f. When the background noise exceeds the threshold reference level the data sampling unit is activated to sample AE at a much higher rate F. Therefore AE is sampled at a high rate only when the pump or other machine under test is running and at a low rate when the article under test is not operating. The AE testing device also includes a frequency spectrum correlator which allows background noise to activate the increased sampling rate only if the noise is in a given frequency range.

Abstract: An evaporimeter formed of a capillary tube hydraulically coupled to a sheet of filter paper to form a capillary system establishing hydraulic continuity of liquid between the tube and the surface of the filter paper is automatically replenished with the liquid as the liquid evaporates. The rate of evaporation from the surface of the filter paper of a liquid, such as water, in the tube and filter paper is automatically measured using a photoelectric sensor as the air-liquid interface moves upwardly in the tube as the water is drawn from the tube to replace the evaporated water.

Abstract: In order to determine the boiling point of a liquid, especially a nonaqueous one such as a brake fluid, a device suspended in a body of that liquid--e.g. in a reservoir supplying fluid to a brake cylinder--forms a narrow chamber which is downwardly open and upwardly closed and which contains means for heating the liquid in that chamber and measuring its temperature; the two functions can be simultaneously performed by a thermistor. When the boiling point is reached and the liquid in the chamber is vaporized, a lessening of the heat conduction to the main body of liquid results in a steep rise in temperature; the boiling point marked by this event can be read on a meter and/or qualitatively indicated by differently colored lights, for example. An excessive temperature rise early in the test will also show an unduly low liquid level in the reservoir.

Abstract: An ultrasonic imaging equipment employing a transducer which includes an acoustic propagating medium formed with a concave surface at one end thereof and formed with a piezoelectric thin film on the other end thereof opposing to the one end, and a medium arranged in the concave surface in order to permit the concave surface to effect a lens action, and a dummy transducer which eliminates a transmitted echo and an echo from the lens boundary and which is constructed of the acoustic propagating medium and an acoustic absorber.

Abstract: Sheet or plate stock is used as to defects by a row of ultrasonic transmitting transducers on one side and receiving transducers on the other. The transmitting transducers receive frequency-modulated signals via individual buffers, and the receiving transducers feed individual, digital amplitude envelope minima to detection circuits whose outputs are fed to a computer which also feeds operating parameters to the source for the modulated signals. Different types (autonomy) of the receiver channels are described as well as diagnostic and setup procedures.

Abstract: A digital type ultrasonic holography apparatus includes a clock generator for generating a clock pulse signal having a fixed period, a transducer for transmitting spike-like ultrasonic pulses toward an object in synchronism with trigger pulses derived through the frequency division of the clock pulse signal and receiving the reflected wave from the object, a waveform shaping circuit for shaping the received wave into a digital pulse signal, a coincidence detecting circuit for narrowing the pulse width of the digital pulse signal to a magnitude shorter than the period of the clock pulse signal and judging whether or not the pulse width-narrowed digital pulse is present at the level-changing time of the clock pulse signal, thereby to generate a coincidence signal, a scanner for scanning the transducer, and a device for displaying a hologram of the object in accordance with the value of the coincidence signal and the scanning of the transducer.

Abstract: A cylinder containing a vacuum lid opening at one end and a tee connector is used as a containment vessel to measure the rate of volatilization of dissolved volatiles from solids. One end of the tee is connected to a vacuum pump and the other end is attached to a vacuum pressure gauge. A thermal sensor is located at the bottom end of the cylinder for monitoring the temperature of the solid material. In operation, a sample of contaminated solid is placed in the cylinder, the vacuum pump is activated and the vacuum pressure and solid temperature are monitored over a period of time. The mass transport coefficient for volatilization of dissolved gases from contaminated solids can be determined from Henry's law and a mass transport equation.

Abstract: An evaporimeter is formed of a capillary tube hydraulically coupled to a sheet of filter paper to form a capillary system establishing hydraulic continuity of liquid between the tube and the surface of the filter paper. The rate of evaporation from the surface of the filter paper of a liquid such as water in the tube and filter paper is measured by the water front movement in the tube as the water is drawn from the tube to replace the evaporated water.

Abstract: Ultrasonic inspection of a structure such as steel tubing is enhanced by moving the ultrasonic wave transmitter and receiver through the pipe and periodically injecting an ultrasonic pulse into the tube. Reflected waves are received during a sample period after each pulse injection. By proper selection of linear displacement between pulses and the sample time interval, the time reference of received signals can be adjusted whereby signals reflected from only one direction are coherently added.

Abstract: A method for determining the quality of a vapor wherein a representative sample is heated at constant volume to a superheated or compressedliquid state so that a measurement of the pressure and temperature in this state, in addition to knowing the pressure or temperature of the vapor, will uniquely determine the vapor quality by means of an appropriate relationship. The method is not limited to the degree of wetness and does not require calibration.

Abstract: A dish transducer unit comprising a dish-defining structure into which a drop of sample fluid is dropped for contact with the electrical or electrochemical transducer of the transducer, both the dish-defining structure and the transducer unit being thermostatically heated. The technician presses a button to initiate a timer, whereupon a transducer warm-up period begins, during which the meter connected to the transducer is maintained inoperative, to preclude readings. When the transducer warm-up period ends, the meter becomes operative so that the technician can calibrate. Prior to completion of a timed calibration period, the technician must drop the sample into the dish-defining structure, or else the timer stops and the thermostatic heating is discontinued. If the sample is timely dropped, a sample warm-up period follows, during which the sample is heated and the meter again inoperative, followed by a reading-taking interval during which the meter is again operative.

Abstract: An improved apparatus for measuring high-boiling components and particularly existent gum levels in aviation fuel comprising: a piezoelectric crystal, a lipophobic coating applied to the crystal for controlling sample location, a supply device for applying a sample to the crystal, a heater for heating the sample on the crystal, an evacuator, an oscillator associated with the crystal for measuring the resonant frequency thereof and an insulated housing for the crystal and heater.

Abstract: A signal processor is provided which uses an analog integrating circuit in conjunction with a set of digital counters controlled by a precision clock for sampling timing to provide an improved presentation of an ultrasonic transmitter/receiver signal. The signal is sampled relative to the transmitter trigger signal timing at precise times, the selected number of samples are integrated and the integrated samples are transferred and held for recording on a strip chart recorder or converted to digital form for storage. By integrating multiple samples taken at precisely the same time with respect to the trigger for the ultrasonic transmitter, random noise, which is contained in the ultrasonic receiver signal, is reduced relative to the desired useful signal.

Abstract: A method for ultrasonic inspection of materials in which a reception and processing of ultrasonic vibrations reflected from a material being inspected is followed by separating signals from noise at a level that for each period of radiating ultrasonic vibrations is automatically set to be equal to the mean noise power per interval of time selected within the maximum sensitivity zone of a preceding period of radiating ultrasonic vibrations.

Abstract: According to the proposed method for ultrasonic inspection of materials, a eception and processing of ultrasonic vibrations reflected from a material being tested are followed by separating signals from noise at a preset level, which is carried out by means of time selection of signals performed within time intervals during which the signals' amplitudes exceed the preset level. In the device for effecting the method of this invention, an output of an ultrasonic generator, whose input is connected to one of the outputs of a synchronizer, is connected to an input of an ultrasonic converter acoustically coupled to the material being tested. An output of the ultrasonic converter is connected to an input of a reflected ultrasonic vibrations preprocessing unit whose output is electrically coupled to one of inputs of a signals recording unit.

Abstract: Electro-optical gaging system has an electronic camera which develops a raw camera pulse having a width that approximates the dimension between edges of an object imaged on the camera. A camera pulse processor employs edge detecting techniques using raw pulse differentiators, threshold detectors, zero cross-over detectors, and an autocorrelator to eliminate differentiator-generated noise. This processor produces a precise output pulse that accurately defines the object edge dimension and may be used to drive A/D measuring and/or converting circuits.

Abstract: A method for detecting contamination of a liquid, particularly a Quench Oil, comprises introducing a sensing element at a high temperature into a liquid, allowing the sensing element to commence cooling, and thereafter timing the cooling of the sensing element between two selected temperatures. The time thus measured is compared with a pre-set time, to provide an indication of contamination of the liquid. In apparatus for carrying out the method, a slug of stainless steel in which is embedded a thermo couple is heated in a furnace and then lowered into a receptacle containing the liquid under test. These operations, and the timing and comparison, are effected in a pre-determined automatic cycle.

Abstract: The apparatus comprises a test tube having substantially the same composition as the heat-exchanger tube suspected as fouling internally. A pressure chamber encloses this test tube and forms a space around the test tube and isolated from external influences. This pressure chamber has means for filling the space around the test tube with a vapor that condenses to liquid on the outside of the test tube, the pressure in the pressure chamber being dependent on whether or not or the degree the vapor condenses to liquid on the test tube. Means are provided for measuring the fluid pressure on the inside of the pressure chamber, this means providing a measure of the heat exchange between the vapor and any medium flowing inside of the test tube.