US3842819A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ignition devices
Assignee: Associated Engineering Ltd
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Filing: 1972-11-16
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Granted: 1974-10-22
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Expires: 1992-11-16
Abstract
Abstract An ignition device for an internal combustion engine has a chamber provided with a hole through which the chamber communicates with a medium to be ignited and includes first and second electrodes defining between them a first gap transverse to the hole, and a third electrode defining a second gap between itself and one of the first and second electrodes. A potential is applied between the first and second electrodes which is insufficient by itself to cause electrical breakdown of the first gap, and a higher potential is applied across the second gap so as to cause breakdown of the first gap, and thereby to cause the potential applied to the first and second electrodes to discharge across the first gap.
Inventors
- 👤 F Atkins
- 👤 K Waterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:12
CPC Classifications
F; F02; F02P; F02P9/00; F02P9/002; F02P9/007
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
166 words
An ignition device for an internal combustion engine having means for providing first and second potential differences, said ignition device comprising: a chamber having a wall perforated by a hole through which said chamber is in communication with a medium to be ignited, and means to produce a plasma flame which projects through said hole to ignite said medium, said means including first and second electrodes defining therebetween a first gap transverse to said hole and having a breakdown potential too great to break down when only said first potential difference is applied across said electrodes, and a third electrode defining between itself and one of said first and second electrodes a second gap having a breakdown potential such that it breaks down when said second potential difference is applied across it, thus causing ionization in said first gap when said first potential is simultaneously applied across said first gap, with a consequent electrical discharge across said first gap which causes said plasma flame to occur.
Claim 2
Dependent Claim
166 words
An ignition device for an internal combustion engine having means for providing first and second potential differences, said ignition device comprising: a chamber having a wall perforated by a hole through which said chamber is in communication with a medium to be ignited, and means to produce a plasma flame which projects through said hole to ignite said medium, said means including first and second electrodes defining therebetween a first gap transverse to said hole and having a breakdown potential too great to break down when only said first potential difference is applied across said electrodes, and a third electrode defining between itself and one of said first and second electrodes a second gap having a breakdown potential such that it breaks down when said second potential difference is applied across it, thus causing ionization in said first gap when said first potential is simultaneously applied across said first gap, with a consequent electrical discharge across said first gap which causes said plasma flame to occur.
Claim 3
Dependent Claim
19 words
An ignition device as claimed in claim 1 in which the second potential difference is greater than the first.
Claim 4
Dependent Claim
18 words
An ignition device as claimed in claim 1, including a further gap in series with said third electrode.
Claim 5
Dependent Claim
18 words
An ignition device as claimed in claim 3, wherein said series gap is wider than said second gap.
Claim 6
Dependent Claim
25 words
An ignition device as claimed in claim 1 wherein the first and second electrodes are aligned, so that the first gap is between their ends.
Claim 7
Dependent Claim
38 words
An ignition device as claimed in claim 1, wherein the first and second electrodes are in staggered relationship so that the first gap is between their ends but at right angles to the longitudinal axes of the electrodes.
Claim 8
Dependent Claim
17 words
An ignition device as claimed in claim 1, wherein the third electrode is coaxial with the hole.
Claim 9
Dependent Claim
35 words
An ignition device as claimed in claim 1, wherein the chamber is formed in a body of insulating material and the first and second electrodes form at least part of a wall of the chamber.
Claim 10
Dependent Claim
25 words
An ignition device as claimed in claim 8, wherein the first and second electrodes are exposed at a surface of the device adjacent the hole.
Claim 11
Dependent Claim
31 words
An ignition device as claimed in claim 8, wherein the device includes an outer threaded portion for mating with the threads of a spark plug aperture in an internal combustion engine.
Claim 12
Dependent Claim
40 words
An ignition device as claimed in claim 10, wherein the threaded portion is formed on a metal member which surrounds the body of insulating material, said metal member also having a part defining one of said first and second electrodes.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-21 | 1978-04-22 | 1978-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-21 | 1982-04-22 | 1982-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-21 | 1986-04-22 | 1986-10-22 | $7700.00 | Window Closed / Lapsed |