US3776135A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Non-electric blasting cap assembly
Assignee: Ireco Inc
•
Filing: 1972-06-29
•
Granted: 1973-12-04
•
Expires: 1992-06-29
Abstract
Abstract Non-electric blasting caps, preferably of the delay type, containing a shell closure plug of new configuration, including a perforation extending through the shell and a constriction in the perforation intermediate the ends thereof to divide the perforation into upper and lower sections. The constriction is cross-sectionally dimensioned to retard egress of heat and pressure from the lower perforation section passed thereinto from combustion of one or more of the charges in the ignition area, when the combustion is initiated by action of a detonator cord positioned in the perforation. The volume of the lower perforation section is correlated with the cross-sectional dimension of the constriction to permit egress of sufficient heat and pressure from the combustion for maintaining integrity of the shell while retaining sufficient heat and pressure for the combustion to propagate the resulting burning front for subsequent detonation of the base charge. A further feature of the invention is means, such as a web, or diaphragm, at least partially closing the perforation intermediate the constriction and the ingress end of the perforation for the detonator cord, as a blocking member for spacing the cord in the perforation, albeit the constriction, per se, can serve, without further means, as that stopping means.
Inventors
- 👤 D Zebree
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:47
CPC Classifications
F; F42; F42D; F42D1/00; F42D1/04
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
285 words
In a non-electric blasting cap assembly, a closed shell including a plug closure member therefor, a base explosive charge, and an ignition-primer charge system, with or without delay range, disposed in said shell for operative relationship with a detonator cord for detonation of said base charge when said cord is disposed in said plug as described hereinafter, said plug closure containing a perforation extending therethrough in communication with the outside of said shell and with the interior thereof, a constriction in the cross-section of said perforation intermediate the ends thereof and dividing said perforation into an adjacent lower section extending to the shell interior and an adjacent upper section extending to the outside of said shell and adapted to coaxially accept along at least a portion of its length, said detonator cord extending thereinto from outside said shell, means in said perforation at least partially closing same and disposed ahead of said cord, when extending into said perforation as described, so as to interceptively block extension of said cord beyond said upper perforation section, and said constriction adaptable to constitute said means, said constriction cross-sectionally dimensioned to retard egress of heat and pressure from said lower perforation section passed thereinto from combustion of one or more of said charges when said combustion is initiated by detonating action of said cord extending into said perforation as described, and said lower perforation section having a volume correlated with the cross-sectional dimension of said constriction so as to permit egress of sufficient heat and pressure from said combustion for maintaining integrity of said shell while retaining sufficient of said heat and pressure for said combustion to propagate the resulting burning front for subsequent detonation of said base charge.
Claim 2
Dependent Claim
285 words
In a non-electric blasting cap assembly, a closed shell including a plug closure member therefor, a base explosive charge, and an ignition-primer charge system, with or without delay range, disposed in said shell for operative relationship with a detonator cord for detonation of said base charge when said cord is disposed in said plug as described hereinafter, said plug closure containing a perforation extending therethrough in communication with the outside of said shell and with the interior thereof, a constriction in the cross-section of said perforation intermediate the ends thereof and dividing said perforation into an adjacent lower section extending to the shell interior and an adjacent upper section extending to the outside of said shell and adapted to coaxially accept along at least a portion of its length, said detonator cord extending thereinto from outside said shell, means in said perforation at least partially closing same and disposed ahead of said cord, when extending into said perforation as described, so as to interceptively block extension of said cord beyond said upper perforation section, and said constriction adaptable to constitute said means, said constriction cross-sectionally dimensioned to retard egress of heat and pressure from said lower perforation section passed thereinto from combustion of one or more of said charges when said combustion is initiated by detonating action of said cord extending into said perforation as described, and said lower perforation section having a volume correlated with the cross-sectional dimension of said constriction so as to permit egress of sufficient heat and pressure from said combustion for maintaining integrity of said shell while retaining sufficient of said heat and pressure for said combustion to propagate the resulting burning front for subsequent detonation of said base charge.
Claim 3
Dependent Claim
25 words
In a non-electric blasting cap assembly of claim 1, said closed shell being tubular, and said plug substantially coaxially disposed as an end closure therefor.
Claim 4
Dependent Claim
30 words
In a blasting cap assembly of claim 2, said means for interceptively blocking extension of the cord disposed intermediate said constriction and the opposite end of said upper perforation section.
Claim 5
Dependent Claim
38 words
In a blasting cap assembly of claim 3, a diaphragm closing said perforation as said means for blocking extension of the cord, and rupturable by force from detonation of said cord when extended into said perforation as described.
Claim 6
Dependent Claim
33 words
In a blasting cap assembly of claim 4, a crimp about the periphery of said shell extending through said plug closure into said perforation, as said constriction, in a plane subjacent said diaphragm.
Claim 7
Dependent Claim
21 words
In a blasting assembly of claim 2, said constriction adapted to also constitute said means for blocking extension of said cord.
Claim 8
Dependent Claim
27 words
In a blasting cap assembly of claim 6, a crimp about the periphery of said shell and extending through said plug into said perforation as said constriction.
Claim 9
Dependent Claim
50 words
In a blasting cap assembly of claim 3, a crimp disposed about the periphery of said shell extending through said plug and into said perforation intermediate said constriction and the opposite end of said upper section to partially close said perforation as said means for blocking extension of the cord.
Claim 10
Dependent Claim
31 words
In an assembly of claim 5, said diaphragm integral with said plug member, and closure means for said shell, integral therewith, at the end of said shell opposite said closure plug.
Claim 11
Dependent Claim
41 words
In an assembly of claim 9, a base charge, a primer charge, a delay charge and an ignition charge disposed contiguously in that order from the integrally closed end of said shell, and said plug member superposed on said ignition charge.
Claim 12
Dependent Claim
38 words
In a blasting cap assembly of claim 2, a diaphragm in transverse water-tight closing relationship with said lower perforate section, and rupturable in response to force of detonation of said cord when extending into said perforation as described.
Claim 13
Dependent Claim
56 words
In a blasting cap assembly of claim 2, a diaphragm in water-tight closing relationship with said upper perforate section in a plane in the portion thereof accepting said cord, in open communication with the outside of said shell, and yieldable to penetrating action of said cord when said cord is extended within said perforation as described.
Claim 14
Dependent Claim
24 words
In a blasting cap assembly of claim 5, a detonator cord extending into said upper perforate section into substantially abutting contact with said diaphragm.
Claim 15
Dependent Claim
25 words
A blasting cap assembly of claim 13 wherein the core loading of said cord is from 2 to 7 grains per foot (PETN or equivalent).
Claim 16
Dependent Claim
24 words
In a blasting cap assembly of claim 5, a detonator cord extending into said upper perforate section into spaced apart relationship with said diaphragm.
Claim 17
Dependent Claim
25 words
A blasting cap assembly of claim 15 wherein the core loading of said cord is from 2 to 25 grams per foot (PETN or equivalent).
Claim 18
Dependent Claim
22 words
A blasting cap assembly of claim 1 containing a delay charge having a burning rate faster than about 3 seconds per inch.
Claim 19
Dependent Claim
48 words
A blasting cap assembly of claim 1 containing a delay charge having a burning rate slower than about 3 seconds per inch; and, as an ignition system, an ignition charge, with or without a wafer charge, having a heat of reaction of at least 110 calories per gram.
Claim 20
Dependent Claim
15 words
A blasting cap assembly of claim 18 containing said ignition and wafer charges in combination.
Claim 21
Dependent Claim
30 words
A blasting cap assembly of claim 19, wherein the heat of reaction of said combination of ignition and wafer charges is within the range of about 400-600 calories per gram.
References Cited (Backward Citations)
US1293354A
Cited
US1599078A
Cited
GB855749A
Cited
US3020844A
Cited
US3238876A
Cited
US3587466A
Cited
US3713392A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-03 | 1977-06-04 | 1977-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-03 | 1981-06-04 | 1981-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-03 | 1985-06-04 | 1985-12-04 | $7700.00 | Window Closed / Lapsed |