Patent US2427933A successfully refreshed from Google Patents.
US3698321A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rocket assisted projectile
Assignee: ATK Launch Systems LLC
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Filing: 1969-10-29
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Granted: 1972-10-17
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Expires: 1989-10-29
Abstract
Abstract An improved projectile suitable for use in artillery pieces, through preferably in the higher calibres, is disclosed wherein projectile range upon launching by the gun is considerably extended by means of a solid propellant rocket motor in combination therewith which is characterized by internal means for supporting the solid propellant. Ignition of the propellant produces propulsive gases. The motor is operated after exit from the gun barrel and extends the flight range of the projectile.
Inventors
- 👤 Richard H Wall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:55
CPC Classifications
F; F42; F42B; F42B15/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
213 words
A rocket motor assisted projectile, said motor and projectile launched by a gun the in-flight propulsion means for which is said rocket motor, said motor consisting of a propellant grain having a central perforation and a casing, the inner surface of said casing defining a propellant chamber, said casing terminating at its rear end in at least one nozzle; a supporting tube for said propellant grain, said tube forming the inner wall for said propellant chamber and being connected to said chamber through at least one opening, said grain consisting of a solid propellant having an ultimate strain adapted to withstand relatively high axial and tangential forces when supported by said tube, said supporting tube extending into the central perforation of said grain and having an outer dimension which in a substantial nUmber of cross sections thereof is less than the dimension of the central perforation in said grain, so that the grain during the launch of said projectile from said gun is forced to take support against said tube without cracking, but so that when said axial force ceases said grain returns to its earlier shape and then elongates due to centrifugal force to expose a space between the grain and the supporting tube whereby at least radial burning is rendered possible.
Claim 2
Dependent Claim
213 words
A rocket motor assisted projectile, said motor and projectile launched by a gun the in-flight propulsion means for which is said rocket motor, said motor consisting of a propellant grain having a central perforation and a casing, the inner surface of said casing defining a propellant chamber, said casing terminating at its rear end in at least one nozzle; a supporting tube for said propellant grain, said tube forming the inner wall for said propellant chamber and being connected to said chamber through at least one opening, said grain consisting of a solid propellant having an ultimate strain adapted to withstand relatively high axial and tangential forces when supported by said tube, said supporting tube extending into the central perforation of said grain and having an outer dimension which in a substantial nUmber of cross sections thereof is less than the dimension of the central perforation in said grain, so that the grain during the launch of said projectile from said gun is forced to take support against said tube without cracking, but so that when said axial force ceases said grain returns to its earlier shape and then elongates due to centrifugal force to expose a space between the grain and the supporting tube whereby at least radial burning is rendered possible.
Claim 3
Dependent Claim
81 words
A rocket assisted projectile according to claim 1 wherein the length of the grain is shorter than the length of the rocket chamber, such that a space is formed between the front end of the motor and the front of the grain, so that the grain after launch of said projectile and motor, is elongated by centrifugal forces until until contained by the opposite ends of said rocket chamber, and the space between said grain and said supporting tube becomes larger.
Claim 4
Dependent Claim
23 words
A rocket assisted projectile according to claim 1 wherein said grain is at least partially bonded to said inner surface of said casing.
Claim 5
Dependent Claim
21 words
A rocket assisted projectile according to claim 1 wherein the space between the supporting tube and the grain is substantially uniform.
Claim 6
Dependent Claim
30 words
A rocket assisted projectile according to claim 1 further including a nozzle plug for preventing hot gas from said launching gun charge from entering the interior of said propellant chamber.
Claim 7
Dependent Claim
42 words
A rocket assisted projectile according to claim 5 wherein said plug has a closed orifice and said orifice is adapted to be opened by said gas from said launching gun charge, whereby said gas enters said chamber and ignites said propellant grain.
Claim 8
Dependent Claim
26 words
A rocket assisted projectile according to claim 1 wherein the material of the supporting tube is ablatable by the gases produced by said solid propellant grain.
Claim 9
Dependent Claim
24 words
A rocket assisted projectile according to claim 1 wherein the tube material is selected from the group consisting of aluminum, magnesium and alloys thereof.
Claim 10
Dependent Claim
18 words
A rocket assisted projectile according to claim 1 wherein thickness of the supporting tube walls is substantially uniform.
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) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |