Patent US4475029A successfully refreshed from Google Patents.
US4475029A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ceramic heater
Assignee: Denso Corp
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Filing: 1983-03-01
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Granted: 1984-10-02
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Expires: 2003-03-01
Abstract
Abstract A ceramic heating element is held in a metal housing to be mounted on an internal combustion engine, so that the heating element is operated as a glow plug for igniting an air-fuel mixture. The ceramic heating element is formed of an electrode section housed in the housing and a heat generating section extending out of the housing, whereby the heat generating section is exposed to the mixture in an engine cylinder. The electrode and heat generating sections are divided into two portions, respectively, and both forward ends of divided heat generating portions are connected with each other, so that electric current flows from one of the electrode portions through the divided heat generating portions to the other electrode portion.
Inventors
- 👤 Hitoshi Yoshida
- 👤 Shunzo Yamaguchi
- 👤 Morihiro Atsumi
- 👤 Takeshi Fukazawa
- 👤 Tomio Kumoi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:48
CPC Classifications
F; F23; F23Q; F23Q7/00; F23Q7/001
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
185 words
A ceramic heater for an internal combustion engine comprising: a cylindrical metal housing constructed and arranged to be mounted on an internal combustion engine; a central electrode fixed to one end of said housing and electrically insulated from said housing; a cylindrical ceramic insulating sleeve secured to the other end of said metal housing; and a heating element formed of a ceramic material for generating heat when supplied with electric power, said heat element having (i) an electrode section inserted into and secured to one end of said insulating sleeve, and having a first and a second electrode portions, and (ii) a heat generating section extending out of said insulating sleeve and having a first and a second heat generating portions to be directly exposed to an air-fuel mixture, both forward ends of said first and second heat generating portions being connected with each other, the cross-sectional area of said electrode section being larger than that of said heat generating section; means for electrically connecting said first electrode portion with said metal housing; and means for electrically connecting said second electrode portion with central electrode.
Claim 2
Dependent Claim
185 words
A ceramic heater for an internal combustion engine comprising: a cylindrical metal housing constructed and arranged to be mounted on an internal combustion engine; a central electrode fixed to one end of said housing and electrically insulated from said housing; a cylindrical ceramic insulating sleeve secured to the other end of said metal housing; and a heating element formed of a ceramic material for generating heat when supplied with electric power, said heat element having (i) an electrode section inserted into and secured to one end of said insulating sleeve, and having a first and a second electrode portions, and (ii) a heat generating section extending out of said insulating sleeve and having a first and a second heat generating portions to be directly exposed to an air-fuel mixture, both forward ends of said first and second heat generating portions being connected with each other, the cross-sectional area of said electrode section being larger than that of said heat generating section; means for electrically connecting said first electrode portion with said metal housing; and means for electrically connecting said second electrode portion with central electrode.
Claim 3
Dependent Claim
48 words
A ceramic heater according to claim 1, further comprising: a ceramic insulator inserted into the other end of said insulating sleeve, said ceramic insulator having a pair of grooves extending axially of said insulating sleeve, and said electrically connecting means being received in said pair of grooves, respectively.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-02 | 1988-04-02 | 1988-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-02 | 1992-04-02 | 1992-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-02 | 1996-04-02 | 1996-10-02 | $7700.00 | Window Closed / Lapsed |