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US4307602A Expired / Lapsed US ⏱️ 0.0 years remaining

Knock sensor

Assignee: Toyota Motor Corp
•
Filing: 1979-12-27
•
Granted: 1981-12-29
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Expires: 1999-12-27
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Abstract

Abstract A piezoelectric ceramic vibrator is mounted inside a metal case including a portion adapted for fastening the case to an engine, and the vibrator is adapted to resonate in response to a vibration frequency produced upon knocking of the engine. The output of the vibrator is taken out as a knock output.

Inventors

  • 👤 Daisaku Sawada
  • 👤 Juhei Takahashi
  • 👤 Tadayori Makino
  • 👤 Kenzo Miura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 16:22
CPC Classifications
G; G01; G01L; G01L23/00; G01L23/22; G01L23/221; G01L23/222

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 183 words
A knock sensor for detecting vibrations of an engine comprising: a metal case having a recess and an attachment means for fixing said metal case to a body portion of said engine, a ceramic vibrator mounted inside of said recess, said ceramic vibrator having one end fixed to said metal case by means of a fixing metal plate sandwiching said one end against a surface of said recess, a base plate of electrically insulating material having an electrically conductive layer formed on one surface thereof, said base plate being interposed between said one end of said ceramic vibrator and the surface of the recess of said metal case so that said electrically conductive layer is in contact with said ceramic vibrator, a cable for providing an output signal from said ceramic vibrator, one conductor of said cable having one end electrically connected to one of said fixing metal plate and said metal case, the other conductor of said cable having one end electrically connected to said electrically conductive layer, and a cover covering the recess of said metal case enclosing said ceramic vibrator.
Claim 2
Dependent Claim 183 words
A knock sensor for detecting vibrations of an engine comprising: a metal case having a recess and an attachment means for fixing said metal case to a body portion of said engine, a ceramic vibrator mounted inside of said recess, said ceramic vibrator having one end fixed to said metal case by means of a fixing metal plate sandwiching said one end against a surface of said recess, a base plate of electrically insulating material having an electrically conductive layer formed on one surface thereof, said base plate being interposed between said one end of said ceramic vibrator and the surface of the recess of said metal case so that said electrically conductive layer is in contact with said ceramic vibrator, a cable for providing an output signal from said ceramic vibrator, one conductor of said cable having one end electrically connected to one of said fixing metal plate and said metal case, the other conductor of said cable having one end electrically connected to said electrically conductive layer, and a cover covering the recess of said metal case enclosing said ceramic vibrator.
Claim 3
Dependent Claim 20 words
A knock sensor as set forth in claim 1, wherein said ceramic vibrator is in the form of a cantilever.
Claim 4
Dependent Claim 23 words
A knock sensor as set forth in claim 1, wherein said ceramic vibrator is composed of two ceramic pieces placed one upon another.
Claim 5
Dependent Claim 36 words
A knock sensor as set forth in claim 1, wherein said metal case is formed in a hexagonal shape, and said attachment means is a threaded projection extending outwardly from the bottom of said metal case.

References Cited (Backward Citations)

US3497731A Cited
US4091679A Cited
US4153020A Cited
DE2801969A1 Cited
US4233836A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-12-28 1985-06-29 1985-12-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-12-28 1989-06-29 1989-12-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-12-28 1993-06-29 1993-12-29 $7700.00 Window Closed / Lapsed

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