US4714003A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromagnetic launcher with a passive inductive loop for rail energy retention or dissipation
Assignee: Westinghouse Electric Corp
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Filing: 1985-02-19
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Granted: 1987-12-22
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Expires: 2005-02-19
Abstract
Abstract An electromagnetic projectile launching system is provided with a passive, conductive loop for energy retention, dissipation or recovery. In a parallel rail launcher, this passive loop is inductively coupled to substantially link magnetic flux produced within the launcher by current flowing in a pair of parallel projectile launching rails. During projectile acceleration, parasitic current flow in the passive inductive loop turn or turns is prevented by a rectifier array. When the projectile exits, post-firing rail inductive energy is inductively and rapidly transferred to the passive inductive loop and is either dissipated there or may be beneficially employed to help accelerate a successive projectile.
Inventors
- 👤 George A. Kemeny
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:19
CPC Classifications
F; F41; F41B; F41B6/00; F41B6/006
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
98 words
An electromagnetic projectile launcher comprising: a pair of conductive rails, having a breech end and a muzzle end; a source of electric current; means for switching current from said current source to said rails; means for conducting current between said rails and for propelling a projectile along said rails; means for electrically insulating; a first conductive loop which is electrically insulated by said insulating means from said rails and inductively coupled to said rails to link magnetic flux produced between said rails by current flowing through said rails; and means for controlling current flow in said conductive loop.
Claim 2
Dependent Claim
98 words
An electromagnetic projectile launcher comprising: a pair of conductive rails, having a breech end and a muzzle end; a source of electric current; means for switching current from said current source to said rails; means for conducting current between said rails and for propelling a projectile along said rails; means for electrically insulating; a first conductive loop which is electrically insulated by said insulating means from said rails and inductively coupled to said rails to link magnetic flux produced between said rails by current flowing through said rails; and means for controlling current flow in said conductive loop.
Claim 3
Dependent Claim
39 words
An electromagnetic projectile launcher as recited in claim 1, wherein said means for controlling current flow comprises: circuit elements electrically connected in series with said conductive loop to prevent current flow in said loop during acceleration of said projectile.
Claim 4
Dependent Claim
38 words
An electromagnetic projectile launcher as recited in claim 1, wherein said first conductive loop is positioned substantially within said rails to link substantially all of the magnetic flux produced between said rails by current flowing through said rails.
Claim 5
Dependent Claim
26 words
An electromagnetic projectile launcher as recited in claim 1 wherein said first conductive loop includes conductors which are substantially coaxial with each of said conductive rails.
Claim 6
Dependent Claim
19 words
An electromagnetic projectile launcher as recited in claim 1, wherein said conductive loop comprises: a plurality of transposed conductors.
Claim 7
Dependent Claim
24 words
An electromagnetic projectile launcher as recited in claim 1, further comprising: means for providing ohmic resistance electrically connected in series with said conductive loop.
Claim 8
Dependent Claim
41 words
An electromagnetic projectile launcher as recited in claim 1, wherein said means for switching current comprises: a firing switch connected between the breech ends of said rails; and means for closing said firing switch when said projectile reaches a predetermined position.
Claim 9
Dependent Claim
27 words
An electromagnetic projectile launcher as recited in claim 1, wherein said conductive rails each include a portion of increased electrical impedance located adjacent to the muzzle end.
Claim 10
Dependent Claim
44 words
An electromagnetic projectile launcher as recited in claim 1, further comprising: a second conductive loop electrically connected in series with said first conductive loop and inductively coupled to said rails to link magnetic flux produced between said rails by current flowing through said rails.
Claim 11
Dependent Claim
53 words
An electromagnetic projectile launcher as recited in claim 1, further comprising: a second conductive loop electrically insulated from said first conductive loop and inductively coupled to said rails to link magnetic flux produced between said rails by current flowing through said rails; and means for controlling current flow in said second conductive loop.
Claim 12
Dependent Claim
129 words
An electromagnetic projectile launcher as recited in claim 1, further comprising: a second pair of conductive rails; means for switching current from said current source to said second pair of rails; means for conducting current between said second pair of rails and for propelling a second projectile along said second pair of rails; a controllable switch electrically connected in series with said first conductive loop; a second conductive loop electrically connected across said controllable switch and inductively coupled to said second pair of rails to link magnetic flux produced between said second pair of rails by current flowing through said second pair of rails; and means for opening said controllable switch when current flow in said first pair of conductive rails ceases following the acceleration of said first projectile.
Claim 13
Dependent Claim
21 words
An electromagnetic projectile launcher as recited in claim 1, further comprising: an electrical energy storage means connectable into said conductive loop.
Claim 14
Dependent Claim
48 words
An electromagnetic projectile launcher as recited in claim 12, wherein said means for shorting said energy storage device comprises: a switch electrically connected across said energy storage device; and means for opening said switch when the current flow in said rails ceases following a launch of said projectile.
Claim 15
Dependent Claim
19 words
An electromagnetic projectile launcher as recited in claim 12, further comprising: means for electrically shorting said energy storage device.
Claim 16
Dependent Claim
18 words
An electromagnetic projectile launcher as recited in claim 14, wherein said electrical energy storage means comprises a capacitor.
Claim 17
Independent Claim
85 words
A method of inhibiting arcing at muzzle ends of a pair of projectile launching rails of a parallel rail electromagnetic projectile launcher following the launch of a projectile, said method comprising the steps of: placing a conductive loop adjacent to and electrically insulated from said pair of projectile launching rails to link magnetic flux produced by current flowing in said rails; and controlling current in said conductive loop to prevent induced current flow during projectile acceleration and to permit induced current flow after projectile acceleration.
Claim 18
Independent Claim
85 words
A method of inhibiting arcing at muzzle ends of a pair of projectile launching rails of a parallel rail electromagnetic projectile launcher following the launch of a projectile, said method comprising the steps of: placing a conductive loop adjacent to and electrically insulated from said pair of projectile launching rails to link magnetic flux produced by current flowing in said rails; and controlling current in said conductive loop to prevent induced current flow during projectile acceleration and to permit induced current flow after projectile acceleration.
Claim 19
Independent Claim
92 words
A method of recovering energy stored in a pair of projectile launching rails of a parallel rail electromagnetic projectile launcher following the launch of a projectile, said method comprising the steps of: placing a conductive loop adjacent to and electrically insulated from said pair of projectile launching rails to link magnetic flux produced by current flowing in said rails; controlling current in said conductive loop to prevent induced current flow during projectile acceleration and to permit induced current flow after projectile acceleration; and connecting an energy storage means into said conductive loop.
Claim 20
Independent Claim
92 words
A method of recovering energy stored in a pair of projectile launching rails of a parallel rail electromagnetic projectile launcher following the launch of a projectile, said method comprising the steps of: placing a conductive loop adjacent to and electrically insulated from said pair of projectile launching rails to link magnetic flux produced by current flowing in said rails; controlling current in said conductive loop to prevent induced current flow during projectile acceleration and to permit induced current flow after projectile acceleration; and connecting an energy storage means into said conductive loop.
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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) | 1990-12-21 | 1991-06-22 | 1991-12-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-12-21 | 1995-06-22 | 1995-12-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-12-21 | 1999-06-22 | 1999-12-22 | $7700.00 | Window Closed / Lapsed |