US3722480A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary combustion engine with improved firing channel
Assignee: John Deere Technologies International Inc
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Filing: 1971-12-20
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Granted: 1973-03-27
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Expires: 1991-12-20
Abstract
Abstract A rotary combustion engine having in its housing an insert coaxial with the spark plug, to define the shape and volume of the spark plug chamber and of the firing channel between the spark plug and the combustion chamber. The insert is formed of material of high heat resistance and high heat conductivity, and is contoured to provide smooth gas flow and to obviate areas of high heat concentration; the insert has its hoop strength relieved to enhance retention in the housing wall.
Inventors
- 👤 M Berkowitz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:28
CPC Classifications
H; H01; H01T; H01T13/00; H01T13/02; H01T13/08; F; F02; F02B; F02B53/00; F02B53/12; F02B1/00; F02B1/02; F02B1/04; F02B2053/005; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
184 words
A rotary combustion engine with external ignition having a housing and a rotor mounted therein for relative rotation, the housing having a smooth inner surface swept by sealing elements carried by the rotor, the housing having in a wall thereof at least one spark plug cavity communicating with the interior of the housing and a spark plug installed in the cavity, wherein the improvement comprises: a. an insert having approximately the same outer diameter as the cavity and positioned therein in interference engagement with the housing wall with its inner end flush with the smooth housing surface, b. the other end of the insert having therein a counterbore of greater diameter and depth than the nose of the spark plug, the nose of the spark plug being received within the counterbore in a nesting relationship and slightly spaced apart therefrom, c. the insert having a firing channel communicating with the counterbore and coaxial therewith and having an orifice at the inner end of the insert, the firing channel being faired into the counterbore of the insert without arrises to provide smooth gas flow therethrough.
Claim 2
Dependent Claim
184 words
A rotary combustion engine with external ignition having a housing and a rotor mounted therein for relative rotation, the housing having a smooth inner surface swept by sealing elements carried by the rotor, the housing having in a wall thereof at least one spark plug cavity communicating with the interior of the housing and a spark plug installed in the cavity, wherein the improvement comprises: a. an insert having approximately the same outer diameter as the cavity and positioned therein in interference engagement with the housing wall with its inner end flush with the smooth housing surface, b. the other end of the insert having therein a counterbore of greater diameter and depth than the nose of the spark plug, the nose of the spark plug being received within the counterbore in a nesting relationship and slightly spaced apart therefrom, c. the insert having a firing channel communicating with the counterbore and coaxial therewith and having an orifice at the inner end of the insert, the firing channel being faired into the counterbore of the insert without arrises to provide smooth gas flow therethrough.
Claim 3
Dependent Claim
34 words
The combination recited in claim 1, wherein the cavity end of the insert has a plurality of diametral slits thereacross to reduce its hoop strength and to lower the spring rate of the insert.
Claim 4
Dependent Claim
21 words
The combination recited in claim 2, wherein the insert has a funnel-shaped transition portion between the counterbore and the firing channel.
Claim 5
Dependent Claim
47 words
The combination recited in claim 3, wherein the insert slits have concavely arcuate bottoms emerging at the outer circumference of the insert about one-fourth to one-half the axial length of the insert from its cavity end and emerging at the inner circumference in the funnel-shaped transition portion.
Claim 6
Dependent Claim
25 words
The combination recited in claim 2, wherein the insert is formed of copper and has A higher thermal conductivity than the material of the housing.
Claim 7
Dependent Claim
32 words
The combination recited in claim 5, wherein the copper material of the insert contains from about 20 troy ounces of silver to about 30 troy ounces of silver per ton of copper.
References Cited (Backward Citations)
US2560799A
Cited
US3512907A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |