Krautkramer Branson, Inc.

Peter Renzel

Klaus Kroesen

Hanno Jacobs

Werner Vermoehlen

Werner Vermohlen

The invention relates to an ultrasonic test instrument for the nondestructive testing of materials. The instrument includes a transit time measuring circuit and an amplitude and time gate circuit. According to the invention, to measure the amplitudes and the corresponding transit times of a number of echo signals falling within a predetermined measurement range, the output of the amplitude and time gate circuit is connected to the input of a presettable counter which outputs a signal whenever the number of counted pulses is equal to the preset value of the counter. The counter output is connected to the transit time measuring circuit and by way of a second time gate circuit to the amplitude measuring circuit so that amplitude evaluation is carried out only during the time interval defined by the second time gate circuit.

Ultrasonic test instrument

The invention relates to an ultrasonic test instrument, in which a receiver amplifier is controlled in dependence upon time by means of a depth compensation signal or else the ultrasonic signal amplified independently of the depth is evaluated by means of a time-dependent variable threshold signal. The depth compensation signals and the time-dependent threshold signals are derived from the same digital signal values stored in a main memory. The test instrument comprises a microprocessor by means of which the digital signal values for each material requiring testing are automatically measured by the instrument itself in conjunction with whichever test probe is used provided a corresponding test block of this material is available. The microprocessor also controls the circuit generating the depth compensation and threshold signals, so that depending upon the type of operation selected the cathode ray tube can display either the ultrasonic echo responsive signals corrected as a function of depth or the uncorrected ultrasonic signals are shown together with the time-dependent threshold value.

Ultrasonic test instrument with controllable amplifier

An ultrasonic test instrument includes a pulse generator, a receiver, a cathode ray tube screen display and a time gate means providing a gated time interval for viewing only echo signals which arise from a predetermined workpiece region under test. The time gated interval is shown as a horizontal gate bar display on the screen and the length of the bar being indicative of the gated time interval. Circuitry provided generates a reference signal to cause the gate bar to appear at a height commensurate with the echo signal received in the gated intervals having the highest peak amplitude. Unless reset, the amplitude of the gate bar remains at this peak value although subsequent echo signals may have a lower amplitude.

Ultrasonic instrument with time and amplitude gate bar display

The results of the non-destructive testing of objects with a beam of ultrasonic energy is enhanced by generating display control signals commensurate with a precisely defined region in the test object. These region related signals may be displayed as a 'gate' bar on the screen of a cathode ray tube simultaneously with the display of echo related signals. Echo related signals having a magnitude greater than a threshold level, as also defined by the 'gate' bar, are detected and may be employed to energize an alarm.

Ultrasonic test apparatus and sweep voltage generator for use therein

A method and apparatus for determining by the pulse-echo method the acoustic velocity of a workpiece of known thickness utilize measurement of the transit time of the first rear wall echo signal and that of the second rear wall echo signal. The two transit times are then processed in a microprocessor which also controls the entire measuring cycle. For accurate measurement the transit time is defined as the time interval from the leading edge of the trigger pulse, which triggers the transmit pulse generator, to the time at which the respective echo signal exceeds a preset threshold amplitude.

Method and apparatus for determining the acoustic velocity of a workpiece

Echo related signals, commensurate with the results of the non-destructive testing of an object with a beam of ultrasonic energy, are presented along with or alternately with textual information on the screen of a cathode ray tube. The textual information is derived from data permanently stored in a memory of a computer and combined with variable data also stored in a memory of the computer.

Display device for non-destructive testing apparatus

Display of the results of non-destructive testing with a beam of ultrasonic energy is enhanced by exercising precise control over the horizontal sweep voltage which is applied to the deflection plates of a cathode ray tube on which the test information is displayed. The sweep voltage generator produces a sawtooth waveform which has a precisely selectable slope. The sawtooth voltage waveform slope may be adjusted by selecting the capacitance, which is charged from an adjustable constant current source, and by varying the charging current. A microprocessor, which stores information commensurate with various waveform slopes, will control the adjustment of the sawtooth waveform slope by comparison of the stored information with keyboard entered data corresponding to a desired slope.

Display of ultrasound test data

A method and apparatus are provided for converting into digital form the analog ultrasonic echo signals received as a result of cyclically transmitted ultrasonic search signals intercepting an acoustic discontinuity in a workpiece. The ultrasonic echo signals are divided into a discrete number of raster-like scan lines which are scanned electronically by a microprocessor. Digital signals are generated for each line of the raster-like scan and such signals assume either a first or second state along the scan line in accordance with the signal amplitude along that line. As successive scans are made at progressively higher amplitudes of the echo signal, the amplitude required for varying the digital signal between the states for a particular scan line is incrementally increased with each scan line. A comparator receives at a first input the echo signals and at a second input a signal from a digital-to-analog converter whose output is incrementally increased on successive scan lines by the microprocessor. The outputs of the comparator are placed into storage in the microprocessor.

Method and apparatus for converting analog ultrasonic echo signals into

In order to increase the speed at which a workpiece is tested by the ultrasonic pulse-echo method, the dead time between individual measurement time intervals is shortened by providing a minimum predetermined time interval selected for the specific test conditions. When an echo responsive signal is manifest in the receiving circuit, in order to prevent the occurrence of phantom echo signals arising in the following measuring interval, the generation of the succeeding transmit signal is inhibited for the predetermined time interval after receipt of the last echo responsive electrical signal of the measuring interval having an amplitude exceeding a predetermined minimum amplitude. The test speed therefore, is made adaptive to the condition of the receipt of the number of echo responsive electrical signals exceeding a predetermined minimum amplitude.

Growing community of inventors

Duren, Germany

Peter Renzel