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US4664033A Expired / Lapsed US ⏱️ 0.0 years remaining

Pyrotechnic/explosive initiator

Assignee: ET Inc
•
Filing: 1985-03-22
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Granted: 1987-05-12
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Expires: 2005-03-22
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Abstract

Abstract Pyrotechnic/explosive initiator for use with a detonating cord or fuse comprising an elongated hollow tube with a longitudinally extending channel through which a gaseous percussion wave is propagated. The initiator includes a charge of pyrotechnic or explosive material and a valve for cutting off communication between the gas channel and the charge upon initiation of the charge to prevent gases and other reaction products from being exhausted back into the fuse.

Inventors

  • 👤 Frank B. Burkdoll
  • 👤 Harold W. Hannagan

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 16:42
CPC Classifications
C; C06; C06C; C06C7/00; F; F42; F42C; F42C15/00; F42C15/34; F42D; F42D1/00; F42D1/04

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 78 words
In a pyrotechnic/explosive initiator: a fuse having a longitudinally extending gas channel through which a gaseous percussion wave is transmitted, a charge of pyrotechnic explosive material positioned in communication with the gas channel and adapted to be initiated by the percussion wave, and valve means responsive to gas pressure produced by initiation of the charge for closing off communication between the charge and the gas channel to prevent gas produced by the charge from passing into the channel.
Claim 2
Dependent Claim 78 words
In a pyrotechnic/explosive initiator: a fuse having a longitudinally extending gas channel through which a gaseous percussion wave is transmitted, a charge of pyrotechnic explosive material positioned in communication with the gas channel and adapted to be initiated by the percussion wave, and valve means responsive to gas pressure produced by initiation of the charge for closing off communication between the charge and the gas channel to prevent gas produced by the charge from passing into the channel.
Claim 3
Dependent Claim 26 words
The initiator of claim 1 wherein the fuse comprises an elongated hollow tube with a coating of pyrotechnic material on the inner wall of the tube.
Claim 4
Dependent Claim 28 words
The initiator of claim 1 wherein the valve means comprises a seat which faces the charge and a movable valve member positioned between the seat and the charge.
Claim 5
Dependent Claim 13 words
The initiator of claim 3 wherein the valve member comprises a spherical ball.
Claim 6
Dependent Claim 29 words
The initiator of claim 3 wherein one of the valve member and the seat is fabricated of a resilient material, and the other is fabricated of a rigid material.
Claim 7
Dependent Claim 85 words
In a pyrotechnic/explosive initiator for use with a fuse having a longitudinally extending gas channel through which a percussion wave is transmitted: a body having an inlet port to which the fuse is connected, a chamber within the body in communication with the inlet port, a charge of pyrotechnic/explosive material in the chamber which is initiated by the percussion wave from the fuse, and gas pressure responsive valve means for closing off communication between the inlet port and the chamber upon initiation of the charge.
Claim 8
Dependent Claim 85 words
In a pyrotechnic/explosive initiator for use with a fuse having a longitudinally extending gas channel through which a percussion wave is transmitted: a body having an inlet port to which the fuse is connected, a chamber within the body in communication with the inlet port, a charge of pyrotechnic/explosive material in the chamber which is initiated by the percussion wave from the fuse, and gas pressure responsive valve means for closing off communication between the inlet port and the chamber upon initiation of the charge.
Claim 9
Dependent Claim 31 words
The initiator of claim 6 wherein the charge comprises a primary explosive material initiated by the percussion wave and a secondary explosive material initiated by ignition of the primary explosive material.
Claim 10
Dependent Claim 58 words
The initiator of claim 6 including a bore which extends from the chamber, and an impactor disc positioned toward one end of the bore and adapted to be propelled through the bore by ignition of the charge, and a second charge of explosive material positioned toward the other end of the bore for detonating impact by the disc.
Claim 11
Dependent Claim 33 words
The initiator of claim 6 wherein the charge comprises a first-fire pyrotechnic material which is initiated by the percussion wave, and a gas producing pyrotechnic material which is initiated by the first-fire material.
Claim 12
Dependent Claim 27 words
The initiator of claim 6 wherein the valve means comprises a seat which faces the chamber and a movable member positioned between the seat and the chamber.
Claim 13
Dependent Claim 13 words
The initiator of claim 10 wherein the valve member comprises a spherical ball.
Claim 14
Dependent Claim 29 words
The initiator of claim 10 wherein one of the valve member and the seat is fabricated of a resilient material, and the other is fabricated of a rigid material.
Claim 15
Dependent Claim 98 words
In an ignitor: a fuse comprising an elongated hollow tube with a coating of pyrotechnic material on the inner wall thereof, a generally cylindrical sleeve mounted within the bore of the tube toward the distal end thereof with the outer wall of the sleeve in sealing engagement with the inner wall of the tube, a charge of ignitive material spaced from the sleeve toward the distal end of the tube, and a valve member positioned between the sleeve and the charge and being urged into sealing engagement with the sleeve by gases produced by ignition of the charge.
Claim 16
Dependent Claim 98 words
In an ignitor: a fuse comprising an elongated hollow tube with a coating of pyrotechnic material on the inner wall thereof, a generally cylindrical sleeve mounted within the bore of the tube toward the distal end thereof with the outer wall of the sleeve in sealing engagement with the inner wall of the tube, a charge of ignitive material spaced from the sleeve toward the distal end of the tube, and a valve member positioned between the sleeve and the charge and being urged into sealing engagement with the sleeve by gases produced by ignition of the charge.
Claim 17
Dependent Claim 32 words
The ignitor of claim 13 wherein the valve member comprises a spherical ball, and the ignitive charge is spaced from the sleeve by a distance greater than the diameter of the ball.
Claim 18
Dependent Claim 25 words
The ignitor of claim 13 wherein the ignitive charge comprises a mixture of an oxidant and a particulate fuel having a high heat of combustion.

References Cited (Backward Citations)

US3530762A Cited
US3129663A Cited
US3326127A Cited
US3590739A Cited
US3537352A Cited
US3628272A Cited
US3789761A Cited
US3945322A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-05-11 1990-11-10 1991-05-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-05-11 1994-11-10 1995-05-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-05-11 1998-11-10 1999-05-12 $7700.00 Window Closed / Lapsed

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