WO2000039574A1 - Procede et dispositif de controle qualite d'une piece a usiner - Google Patents

Procede et dispositif de controle qualite d'une piece a usiner Download PDF

Info

Publication number
WO2000039574A1
WO2000039574A1 PCT/DE1999/004098 DE9904098W WO0039574A1 WO 2000039574 A1 WO2000039574 A1 WO 2000039574A1 DE 9904098 W DE9904098 W DE 9904098W WO 0039574 A1 WO0039574 A1 WO 0039574A1
Authority
WO
WIPO (PCT)
Prior art keywords
workpiece
vibration
pendulum
measured
spectral components
Prior art date
Application number
PCT/DE1999/004098
Other languages
German (de)
English (en)
Inventor
Volker Sauer
Fawzi Attia
Andreas Frede
Ronny Jahnke
Original Assignee
Robert Bosch Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=7892957&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=WO2000039574(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Robert Bosch Gmbh filed Critical Robert Bosch Gmbh
Priority to JP2000591423A priority Critical patent/JP2002533720A/ja
Priority to EP99967912A priority patent/EP1058842A1/fr
Publication of WO2000039574A1 publication Critical patent/WO2000039574A1/fr

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01HMEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
    • G01H9/00Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01HMEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
    • G01H3/00Measuring characteristics of vibrations by using a detector in a fluid
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01MTESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M7/00Vibration-testing of structures; Shock-testing of structures
    • G01M7/02Vibration-testing by means of a shake table
    • G01M7/022Vibration control arrangements, e.g. for generating random vibrations
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01MTESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M7/00Vibration-testing of structures; Shock-testing of structures
    • G01M7/02Vibration-testing by means of a shake table
    • G01M7/025Measuring arrangements
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04Analysing solids
    • G01N29/045Analysing solids by imparting shocks to the workpiece and detecting the vibrations or the acoustic waves caused by the shocks
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00Indexing codes associated with group G01N29/00
    • G01N2291/02Indexing codes associated with the analysed material
    • G01N2291/028Material parameters
    • G01N2291/02872Pressure

Definitions

  • the invention relates to the non-destructive quality inspection of workpieces.
  • Ultrasound test methods are based on the reflection of ultrasound waves entering a workpiece from cracks or faults in the same. Although such methods are inherently highly sensitive to cracks hidden in the material, ultrasound reflections occur at any interface of a workpiece, which makes the evaluation of ultrasound reflection data that complicates and complexes on irregularly shaped or made of different materials.
  • eddy current methods in which eddy currents are generated in a material to be checked with the aid of a current-carrying coil and disturbances in the course of the current eddies induced by cracks in the material are detected by changing the impedance of the coil
  • leakage flux measuring methods in which from an agnetized workpiece externally displaced magnetic flux, the existence of a crack in the workpiece is only applicable to certain classes of materials.
  • a method and a device for quality inspection of a workpiece in particular for the detection of cracks or defects in a workpiece, are created, the fast and uncomplicated quality inspection of workpieces made of practically any solid materials allow.
  • the effort required to process the measurement signals obtained is low, in particular no complex image processing is required, and the processing effort is essentially independent of the complexity of the shape of the workpiece to be checked.
  • the temporal development of the oscillation amplitude or the frequency of the oscillation can preferably be used as the parameter of the oscillation to be measured.
  • the temporal development can in particular be characterized by the decay time of the oscillation.
  • an excited vibration will always include a plurality of spectral components.
  • frequency and temporal development of individual spectral components can be recorded or monitored.
  • the individual spectral components generally differ in their decay behavior and are influenced in different ways by possible errors in the workpiece. In general, higher-frequency components are more sensitive to errors of small extent than low-frequency ones.
  • the sensitivity of a given spectral component to a disturbance differs depending on whether it is located in the region of an antinode or node of the vibration mode of the workpiece belonging to this component.
  • the decay time of the oscillation and / or individual spectral components of the oscillation is preferably measured and the workpiece is found to be good if the decay time lies in a predetermined interval. This interval can be determined in advance on the basis of experimental parts known to be free of defects.
  • the workpiece is found to be bad if the decay time is within a second predetermined interval.
  • This interval need not be complementary to the first; if inadequately long or short decay times are measured, this is more an indication of a measurement error than of an actual defect in the workpiece being examined. In such a case, it is advisable to check the workpiece using another method. This can also be expedient if the measured value lies between the two predetermined intervals.
  • Measured decay times of the oscillation or of individual spectral components can be different for one and the same workpiece if the Vibration excitation occurs with different strengths. In order to achieve reproducible measurements, it is therefore important that the vibration is reproducibly excited, in particular by striking the workpiece with an object at a fixed speed.
  • a to some extent unavoidable spread of the excitation energy or - which is equivalent - the velocity can be compensated for by the normalization of measurement data, in particular vibration amplitudes, to the excitation energy or velocity.
  • This object is preferably a pendulum deflected with a fixed amplitude.
  • the excited vibration of the workpiece is preferably measured interferometrically.
  • a laser beam is divided into two partial beams, one of them on one Surface area of the workpiece is directed.
  • Laser light reflected from the workpiece is brought into interference with the other partial beam and the interference pattern is evaluated. In this way, the movement of the irradiated surface area of the workpiece can be measured with high accuracy, without the vibration behavior of the workpiece being influenced in any way.
  • the vibration is measured using sound waves emitted by the workpiece through air, for example with the aid of a microphone.
  • An arrangement for carrying out the method according to the invention comprises, in addition to devices for excitation and for measuring the vibration, an oscillatable bearing for the workpiece. Because this mounting is capable of oscillation itself, it is ensured that the vibration of the workpiece is not suppressed at any point, and that consequently errors can be detected in the same way at any point on the workpiece.
  • This storage expediently supports the workpiece at three points. This makes it stable Fixation of the workpiece with minimal restriction of its oscillation ability.
  • the bearing preferably comprises projections, for example in the manner of arms, columns or knobs, made of a rubber-elastic material which supports the workpiece.
  • a simple means of exciting the vibration of the workpiece is a pendulum.
  • a stop element should be provided which defines a maximum deflection of the pendulum.
  • the pendulum has an actuating lever which extends upward beyond the pendulum axis and which an operator can tilt to move the pendulum against the stop element and then release it so that the pendulum can hit the workpiece. After the pendulum has struck the workpiece, the operator can also hold it on the operating lever to prevent a second impact on the workpiece.
  • FIG. 1 shows a schematic representation of a first part of an arrangement for carrying out the method according to the invention, which comprises a device for exciting the vibration;
  • Figure 2 is a schematic representation of the arrangement for performing the method according to the invention including a device for measuring the vibration;
  • Figure 3 is a schematic representation of a variant of the arrangement of Figure 2;
  • FIG. 4 shows a graphical representation of results of a method according to a first embodiment of the invention.
  • Figure 5 is a graphical representation of the results of a method according to a second embodiment.
  • Figure 1 shows a side view of a device for exciting a vibration in a workpiece, which a first part of the arrangement for Implementation of the method according to the invention forms.
  • a base plate 3 On a base plate 3, three columns 2 made of, for example, silicone are mounted, which support a workpiece 1 to be tested, here a cam ring of a radial piston injection pump, at three points near its circumference.
  • the base plate 3 also carries an arm 4 which holds a pendulum 6 rotatable about an axis 5 perpendicular to the plane of the figure.
  • the pendulum comprises an impact body 8 which, in the position shown in solid lines in FIG. 1, just abuts the workpiece 1.
  • the impact body 8 is connected to the axis 5 by a flexible sheet 9, for example made of spring steel.
  • An operating lever 7 above the axis 5 is firmly connected to the sheet 9.
  • the pendulum By tilting the operating lever counterclockwise in FIG. 1, the pendulum reaches the position shown in broken lines in FIG. 1, in which its lower end abuts a stop element 10.
  • This stop element 10 defines the maximum possible deflection of the pendulum.
  • the pendulum can be released from this position and then strikes the workpiece 1 at a precisely defined, reproducible speed. This speed is selected so that it is not sufficient to overcome the static friction of the workpiece 1 on the columns 2 and this to be placed on the pillars slide. Thus, the workpiece 1 and the columns 2 are excited to oscillate with a precisely predetermined energy by the impact with the pendulum.
  • the pendulum After hitting the workpiece 1, the pendulum rebounds and is stopped by the operator before it can hit the workpiece 1 a second time. In this way, the vibration excited by the first impact with the pendulum can end undisturbed.
  • the position of the stop element 10 can be displaceable in order to be able to reproducibly set different pendulum deflections for different types of workpieces which differ, for example in terms of their weight.
  • the support of the workpiece can also be displaceable in order to avoid a second stop directly.
  • an electromagnetic coil can be mounted on the stop element 10, which can have different functions. On the one hand, it can be energized before the start of a measurement in order to hold the impact body 8 on the stop element 10 until the current is interrupted is and thus the pendulum is released to hit the workpiece 1. A short time later, the coil is expediently energized again so that it exerts a magnetic attraction on the pendulum 6 rebounding from the workpiece 1 and pulls it back to the stop element 10.
  • FIG. 2 shows the entire arrangement for carrying out the method, the device for exciting the vibration described with reference to FIG. 1 being shown schematically in a top view.
  • a continuous wave laser 11 for example a HeNe laser, emits a beam which is split into two partial beams at a partially reflecting mirror 12, one of which is reflected on a reflector 13, here a 90 ° prism, and finally reaches a sensor 18, and the second hits a lateral surface of the workpiece 1, which is arranged on the columns 2 (not visible in this figure) on the base plate 3.
  • the reflected beam is fanned out on the convex outer surface of the ring-shaped workpiece 1, part of the reflected light passes through an aperture 14 and returns to the partially reflecting mirror 12 and is reflected in the direction of the sensor 18.
  • a sensor 18, the light reflected by the workpiece 1 is superimposed with the beam reflected by the reflector 13.
  • the reflector 13 is positioned such that the optical path lengths of the two partial beams do not differ by more than the coherence length of the laser light, so that an interference pattern arises at the sensor 18.
  • the amount of light reflected back from the workpiece 1 to the sensor 18 can be maximized.
  • the interferometer arm, which contains the reflector 13 is temporarily blocked, which prevents the formation of an interference pattern on the sensor 18.
  • the measurement signal from the sensor 18 is then a direct measure of the amount of light reflected by the workpiece. This can be optimized, for example, by moving the base plate 3 perpendicular to the direction of the beam coming from the laser 11 or by tilting the base plate.
  • the evaluation electronics comprise, on the one hand, an oscilloscope 19, which directly displays brightness differences occurring at the sensor 18 and thus gives an operator an immediate impression of the course of the vibration excited in the workpiece 1.
  • Another essential component of the evaluation electronics is a computer 20, which receives digitized brightness values from the sensor 18 via an AD converter 21 and is programmed to convert them into instantaneous deflections of the workpiece and to calculate the decay behavior of the entire oscillation therefrom, or possibly also the oscillation break down into their individual spectral components and determine their frequencies and their temporal behavior. Since the vibration modes of the workpiece 1, which correspond to the individual spectral components, are coupled to one another, the temporal behavior of these individual components can be quite complex, for example, depending on the workpiece, beats between individual components can occur, the intensity of individual components can gradually increase after the workpiece 1 has been hit, since vibration energy is only gradually coupled into the corresponding vibration mode, etc.
  • Amplitudes and frequencies of the individual spectral components can be obtained in a simple manner using known processing techniques, such as the fast Fourier transformation, and from one Any deviations of the measured values from standard values previously determined on workpieces known to be error-free can easily be concluded that there is an error in workpiece 1.
  • a screen 22 connected to the computer 20 displays the results of the evaluation, for example as numerical values of the measured frequencies, decay times, etc. Of course, the screen 22 can also display a decision made by the computer 20 about the defectiveness or freedom from defects of the workpiece.
  • FIG. 3 shows a variant of the device in which the vibration of the workpiece 1 is not detected optically-interferometrically, but acoustically with the aid of a microphone 23.
  • the processing of the signal supplied by the microphone 23 is essentially the same as that of the signal supplied by the sensor 18 and is carried out using the same devices 19 to 22.
  • the acoustic examination of the workpiece can also accompany tending to be interferometric.
  • the two variants differ essentially in that the optical signal evaluated in the structure shown in FIG. 2 is obtained only from a locally limited area of the workpiece, while the acoustic signal is an “averaged” signal to which the entire workpiece contributes.
  • the stop 10 contains a magnetic coil, the triggering of the measuring device and the interruption of the current of this coil can take place with a common switch.
  • the computer 20 calculates the instantaneous deflection of the workpiece 1 from its rest position and the amplitude of the oscillation from the brightness values provided by the sensor 18.
  • the decay time is determined by continuously monitoring the amplitude. Previous measurements on the cam rings used here as a workpiece have shown that they normally have a decay time in a range around 800 ms. The computer is therefore instructed to assess a cam ring as correct when the measured decay time is between 600 and 1500 ms. Significantly larger deviations from the normal value are permitted upwards than downwards because a long decay time is generally regarded as an indication of a good, crack-free and trouble-free material structure. If a decay time of more than 1500 ms is measured, there is probably a measurement error. In such a case the measurement can be repeated from the beginning, or ' the cam ring in question is checked by another method.
  • the computer 20 decides that the cam ring is bad. A decay time shorter than 100 ms is in turn an indication of a lack of measurement.
  • the decay time is between 400 and 600 ms, the assessment is not completely certain. In such a case, a low-value workpiece could simply be discarded; for higher-quality workpieces, it can be economical to carry out a check beforehand using another method.
  • FIG. 4 shows a typical result of a check of a batch of 300 cam rings in the form of a diagram, on the axes of which the ordinal number of the respective cam ring or the measured decay time is plotted in ms.
  • the overwhelming majority of the cam rings have decay times that fall within a band between 600 and 1000 ms, which is shown hatched in the figure, and are therefore within the dashed interval of 600 to 1500 ms within which the cam rings are found to be in order.
  • Individual rings, represented by cross 30 in the diagram have decay times between 100 and 400 ms and are therefore sorted out as faulty.
  • FIG. 5 shows the results of a model examination on two different batches of cam rings, which differ in their dimensions.
  • the ordinal numbers of the cam rings are plotted on the axes of the diagram and their resonance frequency in Hz is plotted vertically.
  • the first batch corresponds to the area of the diagram designated I, the second to that designated II.
  • a group of defective cam rings is inserted in the section designated 31 in the first batch.
  • the measured value of each cam ring in this group is indicated by a circle in the diagram. It can be seen that the measured resonance frequencies of the defective cam rings vary widely and are usually below the typical resonance frequency of about 3750 Hz for the batch.
  • Outliers 32 in area I are due to individual defective cam rings or measurement errors.
  • a small group 33 of cam rings of the second batch is inserted into the batch, the resonance frequencies of which are significantly higher at approximately 4050 Hz.
  • the second batch also contains a group 34 of defective cam rings, the measured values of which, denoted by small circles, in comparison to the actual one Scatter the batch heavily and lie lower on average.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
  • Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)

Abstract

L'invention concerne un procédé de contrôle qualité d'une pièce à usiner (1). Ce procédé consiste à exciter (8) la pièce à usiner (1) pour la soumettre à des vibrations et à mesurer (18) au moins un paramètre de vibration. La pièce à usiner est qualifiée de bonne lorsque le paramètre se situe dans des limites prédéterminées.
PCT/DE1999/004098 1998-12-28 1999-12-27 Procede et dispositif de controle qualite d'une piece a usiner WO2000039574A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2000591423A JP2002533720A (ja) 1998-12-28 1999-12-27 工作物の品質検査をする方法および装置
EP99967912A EP1058842A1 (fr) 1998-12-28 1999-12-27 Procede et dispositif de controle qualite d'une piece a usiner

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19860471.8 1998-12-28
DE1998160471 DE19860471C2 (de) 1998-12-28 1998-12-28 Verfahren zur Qualitätsprüfung eines Werkstücks

Publications (1)

Publication Number Publication Date
WO2000039574A1 true WO2000039574A1 (fr) 2000-07-06

Family

ID=7892957

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/DE1999/004098 WO2000039574A1 (fr) 1998-12-28 1999-12-27 Procede et dispositif de controle qualite d'une piece a usiner

Country Status (4)

Country Link
EP (1) EP1058842A1 (fr)
JP (1) JP2002533720A (fr)
DE (1) DE19860471C2 (fr)
WO (1) WO2000039574A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010098822A (ja) * 2008-10-15 2010-04-30 Fanuc Ltd サーボモータ制御装置
DE102011100370A1 (de) * 2011-05-03 2012-11-08 Bundesanstalt für Wasserbau Verfahren und Vorrichtung zur zerstörungsfreien Untersuchung eines Pollers auf Schäden oder der Verankerung
EP1205749B1 (fr) * 2000-10-10 2013-12-04 Snecma Contrôle acoustique de roues aubagées monoblocs

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10333410B4 (de) * 2003-07-15 2017-03-23 Minebea Co., Ltd. Verfahren und Vorrichtung zur Bestimmung der Eigenfrequenzen eines Lagersystems mit einer gelagerten Welle
DE102004018683B3 (de) * 2004-04-17 2005-09-08 Daimlerchrysler Ag Verfahren zur Qualitätsprüfung eines Werkstücks
JP4905836B2 (ja) * 2007-08-01 2012-03-28 SAW&SPR−Tech有限会社 接触角測定装置
DE102022130379A1 (de) 2022-11-16 2024-05-16 Ford Global Technologies Llc Vorrichtung zur Erzeugung von Körperschall, insbesondere in einem Prüfobjekt

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4388832A (en) * 1980-08-06 1983-06-21 Krautkramer-Branson, Inc. Method and apparatus for receiving ultrasonic waves by optical means
EP0379622A1 (fr) * 1986-03-11 1990-08-01 Powertech Labs Inc. Appareil et méthode pour le contrôle de poteaux en bois
WO1997004291A1 (fr) * 1995-07-14 1997-02-06 Brent Felix Jury Procede et appareil permettant d'effectuer des essais de controle et de relaxation des tensions internes

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
HU172832B (hu) * 1976-04-27 1978-12-28 Magyar Vagon Es Gepgyar Sposob i izmeritel'noe ustrojstvo dlja kontrolja vibrogasjahhego ehffekta torzinnykh vibrogasitelej s kolebljajuhhimsja kol'com, napolnennykh vjazkoj zhidkost'ju
DE3810194C1 (fr) * 1988-03-25 1989-08-24 Daimler-Benz Aktiengesellschaft, 7000 Stuttgart, De
DE3943133A1 (de) * 1989-12-28 1991-07-18 Zeuna Staerker Kg Verfahren zur akustischen pruefung von monolithen auf beschaedigung und vorrichtung zur durchfuehrung des verfahrens

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4388832A (en) * 1980-08-06 1983-06-21 Krautkramer-Branson, Inc. Method and apparatus for receiving ultrasonic waves by optical means
EP0379622A1 (fr) * 1986-03-11 1990-08-01 Powertech Labs Inc. Appareil et méthode pour le contrôle de poteaux en bois
WO1997004291A1 (fr) * 1995-07-14 1997-02-06 Brent Felix Jury Procede et appareil permettant d'effectuer des essais de controle et de relaxation des tensions internes

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1205749B1 (fr) * 2000-10-10 2013-12-04 Snecma Contrôle acoustique de roues aubagées monoblocs
JP2010098822A (ja) * 2008-10-15 2010-04-30 Fanuc Ltd サーボモータ制御装置
JP4620148B2 (ja) * 2008-10-15 2011-01-26 ファナック株式会社 サーボモータ制御装置
DE102011100370A1 (de) * 2011-05-03 2012-11-08 Bundesanstalt für Wasserbau Verfahren und Vorrichtung zur zerstörungsfreien Untersuchung eines Pollers auf Schäden oder der Verankerung
DE102011100370B4 (de) 2011-05-03 2020-01-09 Bundesanstalt für Wasserbau Verfahren zur zerstörungsfreien Untersuchung eines Pollers auf Schäden oder auf dessen Verankerungsfestigkeit

Also Published As

Publication number Publication date
EP1058842A1 (fr) 2000-12-13
DE19860471C2 (de) 2000-12-07
JP2002533720A (ja) 2002-10-08
DE19860471A1 (de) 2000-07-06

Similar Documents

Publication Publication Date Title
EP1751535B1 (fr) Procédé et dispositif pour determiner des defauts dans une ailette de turbine par un reseau ultrasonore en phase
DE102007059502B3 (de) Verfahren zum Prüfen eines Rotorblatts einer Windkraftanlage und Prüfvorrichtung
DE3820862A1 (de) Verfahren und vorrichtung zur kontaktlosen untersuchung von oberflaechen und inneren strukturen eines festen pruefkoerpers
DE4428363C2 (de) Röntgen-Mikrodiffraktometer
EP2992321B1 (fr) Procédé et dispositif pour l'evaluation des defauts par saft (synthetic aperture focussing technique)
EP2898322B1 (fr) Procédé et dispositif d'amélioration d'une analyse saft en cas de densité de mesures locale irrégulière
EP1693668A1 (fr) Méthode et appareil pour la détection de defauts dans un élément d'une turbine
WO2000039574A1 (fr) Procede et dispositif de controle qualite d'une piece a usiner
DE3117073A1 (de) Einrichtung zum erkennen des lidschlags waehrend der untersuchung eines auges
DE2238130C3 (de) Verfahren zur Ermittlung und Kompensation von unterschiedlichen Schallschwächungseigenschaften bei der Ultraschall-Werkstoffprüfung
DE60127541T2 (de) Kontrollsystem für widerstandsschweissung
EP1576364B1 (fr) Procede d'evaluation de signaux ultrasonores d'un defaut d'une piece
EP1576363B1 (fr) Appareil d'essai ultrasonore et procede d'evaluation de signaux ultrasonores
DE102012002127B3 (de) Verfahren und Vorrichtung zur Erkennung von Oberflächenrissen
EP1690084B1 (fr) Procédé et dispositif pour tester un élément structurel par ultrasons, ainsi qu'utilisation du procede et du dispositif
DE102020214570A1 (de) Vorrichtung und Verfahren zur berührungslosen Streuflussmessung
DE19849102C1 (de) Verfahren und Vorrichtung zur zerstörungsfreien Prüfung von Gegenständen auf oberflächenoffene und/oder oberflächennahe Fehlstellen
WO2019219596A1 (fr) Procédé d'ajustement et de calibrage de bancs d'essai pour le contrôle par ultrasons de pièces
DE3633556A1 (de) Vorrichtung zur zerstoerungsfreien pruefung von bauteilen aus faserverstaerkten verbundwerkstoffen und sonstigen werkstoffen mit starker ultraschallstreuung auf kleinste fehler
WO2002073123A1 (fr) Tete palpeuse dotee d'une tare
DE3743560C1 (en) Method for testing the noise development of safety belt retractors of motor vehicles and device for carrying out the method
DE102004030154A1 (de) Verfahren zur Prüfung der Qualität einer mechanischen Verbindung
DE4109029C1 (en) Operating ultrasonic workpiece tester - measuring time period of receiver oscillation effected by transmitted HF pulse
DE2251426A1 (de) Pruefsystem zur unterscheidung der formechos von fehleranzeigen bei der ultraschall-werkstoffpruefung
DE4118757A1 (de) Verfahren und winkelpruefkopf zum zerstoerungsfreien pruefen von plattierten werkstuecken mittels ultraschallwellen im impuls-echo-verfahren

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE

WWE Wipo information: entry into national phase

Ref document number: 1999967912

Country of ref document: EP

121 Ep: the epo has been informed by wipo that ep was designated in this application
WWP Wipo information: published in national office

Ref document number: 1999967912

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 09623064

Country of ref document: US

WWR Wipo information: refused in national office

Ref document number: 1999967912

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1999967912

Country of ref document: EP