← Back to Patent Explorer
US4225802A Expired / Lapsed US ⏱️ 0.0 years remaining

Piezoelectric knocking detector for internal combustion engine

Assignee: Denso Corp
•
Filing: 1979-01-09
•
Granted: 1980-09-30
•
Expires: 1999-01-09
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A knocking detector for an internal combustion engine includes a vibration unit comprising an inertial mass member and springs which are mounted in a housing attached to an engine body. The spring constants of the springs are so selected that the resonant frequency of the vibration unit becomes substantilly equal to the frequency of vibration due to knocking of the engine, and the vibration of the vibration unit is detected and converted into an electric signal.

Inventors

  • 👤 Yutaka Suzuki
  • 👤 Osamu Ito
  • 👤 Nobuhito Hobo
  • 👤 Kenji Goto
  • 👤 Daisaku Sawada
  • 👤 Takashi Shigematu
  • 👤 Yuji Takeda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 21:07
CPC Classifications
G; G01; G01L; G01L23/00; G01L23/22; G01L23/221; G01L23/222

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 151 words
A knocking detector for an internal combustion engine comprising: a housing attached to a body of an engine for vibration together with said body; piezoelectric means having one of the opposite faces thereof connected with said housing by way of a first spring and the other face connected by way of inertial mass means and a second spring with conductive means disposed to deliver an electric output to outside; and insulating means attached to said housing to press said piezoelectric means against said housing through said conductive means, said first and second springs and said inertial mass means under a predetermined load, said insulating means electrically insulating said conductive means from said housing; wherein the resonant frequency of a vibration system comprising said inertial mass means and said first and second springs is selected so as to be substantially equal to a frequency of vibration caused by knocking of said engine.
Claim 2
Dependent Claim 151 words
A knocking detector for an internal combustion engine comprising: a housing attached to a body of an engine for vibration together with said body; piezoelectric means having one of the opposite faces thereof connected with said housing by way of a first spring and the other face connected by way of inertial mass means and a second spring with conductive means disposed to deliver an electric output to outside; and insulating means attached to said housing to press said piezoelectric means against said housing through said conductive means, said first and second springs and said inertial mass means under a predetermined load, said insulating means electrically insulating said conductive means from said housing; wherein the resonant frequency of a vibration system comprising said inertial mass means and said first and second springs is selected so as to be substantially equal to a frequency of vibration caused by knocking of said engine.
Claim 3
Dependent Claim 87 words
A detector according to claim 1, wherein said mass means includes first and second recesses respectively formed in the lower and upper surfaces thereof, wherein said piezoelectric means has the one end embedded and held in said first recess and the other end slidably fitted in a depression formed in said housing in opposition to said first recess to press said first spring mounted in said housing depression, and wherein said conductive means is slidably fitted in said second recess to press said second spring mounted therein.
Claim 4
Dependent Claim 31 words
A detector according to claim 2, wherein said second spring is a compression spring, and wherein said piezoelectric means is disposed to press said first spring through a conductive flat plate.
Claim 5
Dependent Claim 149 words
A knocking detector for an internal combustion engine comprising: a housing attached to a body of an engine for vibration together with said body; piezoelectric means having one of the opposite faces thereof connected with said housing and the other face connected by way of a first spring, inertial mass means and a second spring with conductive means disposed to deliver an electric output to outside; and insulating means attached to said housing to press said piezoelectric means against said housing through said conductive means, said first and second springs and said inertial mass means under a predetermined load, said insulating means electrically insulating said conductive means from said housing; wherein the resonant frequency of the vibration system comprised of said inertial mass means and said first and second springs is selected so as to be substantially equal to the frequency of vibration caused by knocking of said engine.
Claim 6
Dependent Claim 149 words
A knocking detector for an internal combustion engine comprising: a housing attached to a body of an engine for vibration together with said body; piezoelectric means having one of the opposite faces thereof connected with said housing and the other face connected by way of a first spring, inertial mass means and a second spring with conductive means disposed to deliver an electric output to outside; and insulating means attached to said housing to press said piezoelectric means against said housing through said conductive means, said first and second springs and said inertial mass means under a predetermined load, said insulating means electrically insulating said conductive means from said housing; wherein the resonant frequency of the vibration system comprised of said inertial mass means and said first and second springs is selected so as to be substantially equal to the frequency of vibration caused by knocking of said engine.

References Cited (Backward Citations)

US2411401A Cited
DE909257C Cited
US3075098A Cited
US2972006A Cited
US3145311A Cited
US3394275A Cited
US3819962A Cited
US4110654A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-09-30 1984-03-31 1984-09-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-09-30 1988-03-31 1988-09-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-09-30 1992-03-31 1992-09-30 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag