Patent US4355561A successfully refreshed from Google Patents.
US4355561A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Projectile launching system with assured current division
Assignee: Northrop Grumman Corp
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Filing: 1980-09-10
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Granted: 1982-10-26
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Expires: 2000-09-10
Abstract
Abstract Series resistance is added to the projectile current loop to assure there will be no premature launching or excessive heating of the projectile armature during the energizing cycle.
Inventors
- 👤 George A. Kemeny
- 👤 John P. Barber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:57
CPC Classifications
F; F41; F41B; F41B6/00; F41B6/006
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
113 words
An electromagnetic projectile launching system comprising: a pair of conductive rails: means for conducting current between said rails and for propelling a projectile from one end of said rails to another; a source of high current; means for commutating current from said current source to said rails connected to said rails in parallel with said means for conducting current and said means for propelling the projectile; and a resistance electrically connected between said current conducting and projectile propelling means and said means for commutating current for limiting the flow of current to said rails prior to the commutation of current to said rails and for carrying the full current during the entire launch.
Claim 2
Dependent Claim
113 words
An electromagnetic projectile launching system comprising: a pair of conductive rails: means for conducting current between said rails and for propelling a projectile from one end of said rails to another; a source of high current; means for commutating current from said current source to said rails connected to said rails in parallel with said means for conducting current and said means for propelling the projectile; and a resistance electrically connected between said current conducting and projectile propelling means and said means for commutating current for limiting the flow of current to said rails prior to the commutation of current to said rails and for carrying the full current during the entire launch.
Claim 3
Dependent Claim
30 words
An electromagnetic projectile launching system as set forth in claim 1, wherein the source of high current comprises an inductive energy storage means, a DC generator and a make switch.
Claim 4
Dependent Claim
57 words
An electromagnetic projectile launching system as set forth in claim 1, wherein the means for commutating current comprises a second pair of conductive rails electrically connected to said first mentioned pair of rails and an armature slidably disposed between said second pair of rails and a source of DC current connected to said second set of rails.
Claim 5
Dependent Claim
28 words
An electromagnetic projectile launching system as set forth in claim 3, wherein the resistance is disposed in at least one of the conductive rails of said second pair.
Claim 6
Dependent Claim
24 words
An electromagnetic projectile launching system as set forth in claim 3 wherein the resistance is disposed in the conductive rails of said second pair.
Claim 7
Dependent Claim
26 words
An electromagnetic projectile launching system as set forth in claim 3 and further comprising means for releasably holding the armature between said second pair of rails.
Claim 8
Dependent Claim
41 words
An electromagnetic projectile launching system as set forth in claim 3, wherein the second pair of conductive rails has at least one insulating strip disposed between a rail and the armature adjacent the attachment to the first pair of conductive rails.
Claim 9
Dependent Claim
35 words
An electromagnetic projectile launching system as set forth in claim 3, wherein the second pair of conductive rails has insulating strips disposed adjacent their trailing ends between the rail and the armature slidably disposed therein.
Claim 10
Dependent Claim
27 words
An electromagnetic projectile launching system as set forth in claim 3, wherein the source of high current comprises an inductive energy storage means and a DC generator.
Claim 11
Dependent Claim
41 words
An electromagnetic projectile launching system as set forth in claim 3 and further comprising means for decelerating the armature disposed between the second set of rails, the decelerating means being disposed at the trailing end of the second pair of rails.
Claim 12
Dependent Claim
21 words
An electromagnetic projectile launching system as set forth in claim 1, wherein the means for commutating current comprises circuit breaking means.
Claim 13
Dependent Claim
19 words
An electromagnetic projectile launching system as set forth in cliam 1, wherein the means for commutating current comprises semiconductors.
Claim 14
Dependent Claim
19 words
An electromagnetic projectile launching system as set forth in cliam 1, wherein the means for commutating current comprises semiconductors.
References Cited (Backward Citations)
US1370020A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-10-25 | 1986-04-26 | 1986-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-25 | 1990-04-26 | 1990-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-25 | 1994-04-26 | 1994-10-26 | $7700.00 | Window Closed / Lapsed |