FR2242902A5 - Cavity detector for refrigeration chamber walls - measures resistance changes of loudspeaker facing the walls - Google Patents

Cavity detector for refrigeration chamber walls - measures resistance changes of loudspeaker facing the walls

Info

Publication number
FR2242902A5
FR2242902A5 FR7331835A FR7331835A FR2242902A5 FR 2242902 A5 FR2242902 A5 FR 2242902A5 FR 7331835 A FR7331835 A FR 7331835A FR 7331835 A FR7331835 A FR 7331835A FR 2242902 A5 FR2242902 A5 FR 2242902A5
Authority
FR
France
Prior art keywords
walls
loudspeaker
resistance changes
cavity detector
refrigeration chamber
Prior art date
Legal status (The legal status 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 status listed.)
Expired
Application number
FR7331835A
Other languages
French (fr)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
DOUCET HENRI FR
Original Assignee
DOUCET HENRI FR
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
Application filed by DOUCET HENRI FR filed Critical DOUCET HENRI FR
Priority to FR7331835A priority Critical patent/FR2242902A5/en
Application granted granted Critical
Publication of FR2242902A5 publication Critical patent/FR2242902A5/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
    • G01H1/00—Measuring characteristics of vibrations in solids by using direct conduction to the detector
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating 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
    • G01N29/04—Analysing solids
    • G01N29/12—Analysing solids by measuring frequency or resonance of acoustic waves

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)
  • Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)

Abstract

The cavity detector uses an electromagnetic resonator in the form of a loudspeaker (1) supplied by the secondary of a transformer (2) whose primary is coupled to a sinusoidal wave source (3), whose frequency varies over the range of operation of the loudspeaker (1). A measuring resistance (4) having a low value in comparison to the loudspeaker resistance is placed in series with the loudspeaker (1), with the potential across the terminals of the resistance (4) displaced on an oscilloscope (5) also receiving the signal from the wave source at its sweep inputs.
FR7331835A 1973-09-04 1973-09-04 Cavity detector for refrigeration chamber walls - measures resistance changes of loudspeaker facing the walls Expired FR2242902A5 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR7331835A FR2242902A5 (en) 1973-09-04 1973-09-04 Cavity detector for refrigeration chamber walls - measures resistance changes of loudspeaker facing the walls

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR7331835A FR2242902A5 (en) 1973-09-04 1973-09-04 Cavity detector for refrigeration chamber walls - measures resistance changes of loudspeaker facing the walls

Publications (1)

Publication Number Publication Date
FR2242902A5 true FR2242902A5 (en) 1975-03-28

Family

ID=9124594

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7331835A Expired FR2242902A5 (en) 1973-09-04 1973-09-04 Cavity detector for refrigeration chamber walls - measures resistance changes of loudspeaker facing the walls

Country Status (1)

Country Link
FR (1) FR2242902A5 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2422718C1 (en) * 2010-02-24 2011-06-27 Общество С Ограниченной Ответственностью "Газпромэнергодиагностика" Procedure for determination of contact place of pipeline with protective jacket in system of main crossing over road

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2422718C1 (en) * 2010-02-24 2011-06-27 Общество С Ограниченной Ответственностью "Газпромэнергодиагностика" Procedure for determination of contact place of pipeline with protective jacket in system of main crossing over road

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Legal Events

Date Code Title Description
ST Notification of lapse