US3763782A - Metal layer initiator - Google Patents

Metal layer initiator Download PDF

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Publication number
US3763782A
US3763782A US00137464A US3763782DA US3763782A US 3763782 A US3763782 A US 3763782A US 00137464 A US00137464 A US 00137464A US 3763782D A US3763782D A US 3763782DA US 3763782 A US3763782 A US 3763782A
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United States
Prior art keywords
element according
electrical detonator
electrode
detonator element
electrical
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Expired - Lifetime
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US00137464A
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English (en)
Inventor
P Roh
H Bendler
U Brede
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Dynamit Nobel AG
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Dynamit Nobel AG
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B3/00—Blasting cartridges, i.e. case and explosive
    • F42B3/10—Initiators therefor
    • F42B3/103—Mounting initiator heads in initiators; Sealing-plugs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B3/00—Blasting cartridges, i.e. case and explosive
    • F42B3/10—Initiators therefor
    • F42B3/195—Manufacture

Definitions

  • Data side of a non-conductive carrier which is inserted into Apr. 24, Germany P a conductive housing one urface contacting a pole piece and the other surface having the bridge UuSn Clt t t EB, R f r d th r pressed against the [51] Int. Cl.
  • F42b 3/12 charge which is electrically connected i the h [58] Field of Search 102/28 EB, 28 R, ing, and conductive means interconnecting the bridge 102/ R on one side of the carrier with the surface of the carrier contacting the pole piece either through a bore in [56] Reerences Cited the carrier or around the periphery thereof.
  • the present invention relates in general to the manufacture of electric detonator elements, such as primer caps, and more particularly to an initiator, having an electrically conductive housing, a pole piece, and an ignitable charge, wherein a carrier of glass or ceramic having metallic layers plated thereon forms an ignition bridge disposed between said pole piece and the ignitable charge, which charge contacts or is in electrically conductive relationship with the conductive housing.
  • the ignition bridge is conventional to form as an extremely thin and very short metallic wire jointed to the housing or the pole piece by soldering or welding.
  • this procedure exhibits the disadvantage that the manufacturing expenses are relatively high, since the dimensions of the individual parts are very small, and accordingly, a large amount of skill and precision is required to flawlessly execute the welding or soldering operations necessary to effect the connection of the incandescent bridge with the poles.
  • suitable materials for the nonconductive carrier element are laminated materials consisting of synthetic resin'materials such as phenol, epoxy, or of unsaturated polyesters, impregnated cellulose paper, cotton, glass fiber, and synthetic fiber fabrics impregnated with unsaturated polyester, or the like.
  • the ignition bridge can also be fashioned, for example, as an extremely thin metallic wire which is held on the non-conductive carrier element, for instance, by means of an adhesive.
  • the thus-produced primer elements possess the disadvantage that the mechanical stability thereof is not sufficiently large to withstand the shock stress arising, for example, by the firing of a projectile, with a sufficient degree of safety.
  • the invention is based on the problem of producing a connection of the conductive ignition bridge with a solid non-conductive carrier material, so that the conductive bridge is provided with an increased mechanical stability. Thereby, it is possible to produce primer elements withstanding an impact stress of up to 500,000 gs (g gravitational acceleration), without the necessity of utilizing a welded or soldered incandescent wire, and thus to fashion these elements with a maximum degree of safety.
  • This invention relates to an electric primer element consisting of an insulating body carrying two lead electrodes and a metallic bridge, which bridge serves to ignite a primer composition upon the passage of current therethrough, which element is characterized in that the insulating body consists of a glass or ceramic carrier material to which the electrodes and the bridge are applied by vaporization, printing, and in a chemical manner.
  • the mechanical strength of this primer element is determined solely by the carrier material. Due to the high mechanical stability of the carrier material, which is made of glass or ceramic, it is possible to press the primer composition against the conductive bridge with a higher pressure, whereby a substantially better thermal contact is established between the conductive bridge and the primer composition than is possible in the usual dipping or dripping process. Thus, it is possible to place pure explosives, for example lead trinitroresorcinate, lead azide, or lead picrate, into a close thermal bond with the primer element, for example by compression.
  • pure explosives for example lead trinitroresorcinate, lead azide, or lead picrate
  • FIG. 1 is a side elevation partly in section of a conventional electrical detonator element
  • FIG. 2 is a side elevation partly in section of an electrical detonator in accordance with the present invention.
  • FIGS. 3a and 3b are bottom elevational and side sectional views of the ignition bridge element used in the device of FIG. 2;
  • FIG. 4 is a side elevation partly in section of a second embodiment of the present invention.
  • FIGS. 5a and 5b are bottom elevational and side sectional views of the ignition bridge element used in the device of FIG. 4;
  • FIG. 6 is a detailed view of the conductive bridge member used on the ignition bridge element of FIGS. 5a and 5b.
  • FIG. 1 shows a conventional electrical primer of the spark gap type.
  • the primer consists of a conductive casing 1 containing, in an insulated manner, a pole 'piece 2.
  • An insulating ring 3 is disposed on the inner side of the pole piece 2, this ring being pressed against the pole piece 2 by means of a conductive supporting ring 4.
  • the gap 5 is formed between the pole piece 2 and a primer composition 6 which is pressed into the area defined laterally by the conductive supporting ring 4, the latter being retained by the casing 1.
  • FIG. 2 shows an electrical primer constructed according to FIG. 1, except that the insulating ring 3 is replaced by a metal covered ignition bridge element 7 constructed as seen in FIGS. 3a and 3b.
  • the structure of the remaining parts of the initiator corresponds to the primer cap illustrated in FIG. 1.
  • the bridge element 7 consists of a carrier 8 in the form of a round disk of glass or a ceramic material, especially sintered aluminum oxide, having a high surface quality and conductive contact members 9 applied to the surfaces of this carrier material.
  • the insulator 8 is provided with a bore 10 made conductive by means of a metallic layer 10' on the surface thereof which extends through the bore, so that electrical contact can be established therethrough to conductive layers 9' on the opposite surface of the carrier.
  • the round disk carrier 7 can be provided with indentations, notches, or it can be flattened on one side by sections, so that the primer element can be inserted or fitted in the housing 1 during the assembly of the initiator in an oriented manner.
  • the bore 10, lined with a conductive material, is connected with one of the contact surfaces 9 by a conductive ignition bridge 11, overlapping both the conductive layer 10 and the contact surface 9 at portions 14. As shown in FIGS. 3a and 3b the contact surface 9" is not electrically connected and serves a support function to ensure proper positioning of the bridge element.
  • the ignition current flows via the pole piece 2 through the metallized bore 10, by way of the ignition bridge 11 to the conductive spacer ring 4, the latter constituting the connection to ground together with the external housing 1.
  • the ignition bridge is heated in such a manner that the primer composition 6 is ignited.
  • FIG. 4 shows another embodiment of the metal layer ignition bridge initiator wherein the current is fed to a bridge electrode constructed according to FIGS. 5a, 5b and 6 using a metallic bracket 12 extending around the periphery of the carrier so as to eliminate need for the bore 10.
  • a metallic bracket 12 extending around the periphery of the carrier so as to eliminate need for the bore 10.
  • an additional layer of insulation 13 is provided therebetween.
  • the current flows, in this embodiment, from the pole piece 2 on the outside via the bracket 12 to the ignition bridge 11, which interconnects the contact surfaces 9.
  • FIGS. 50 and 5b the details of the further embodiment of a metal layer bridge element are shown.
  • the carrier 8 does not have a bore for electrical conducting purposes, but rather utilizes a rerouting or by-pass element 12 made of a conductive material.
  • a rerouting or by-pass element 12 made of a conductive material.
  • FIG. 6 One embodiment of this rerouting element 12 is shown in FIG. 6.
  • a segment has been cut out from the circular surface of the carrier 7, whereby simultaneously space has been made available for the lateral conductive rerouting element 12.
  • the ignition bridge 11 is disposed in the center of the carrrer.
  • the contacting surfaces 9 are applied to the carrier material 8 preferably by the silk screen printing process, wherein conventional material is employed, for example palladium, a palladium silver mixture, palladium gold, platinum silver, platinum gold, nickel, or a silver-aluminum alloy.
  • the thus-applied material is sintered at about l,000 l,100 C.
  • Any bore, such as the bore 10 of the embodiment illustrated in FIG. 2, required in certain cases in the bridge element for establishing electrical contact through the carrier is already provided during the production of the blank. Thereafter, a tantalum or tantalum nitride layer of a specific thickness is deposited thereon by vaporization in a high-vacuum process.
  • silver can be employed as the contact material.
  • a photosensitive layer is applied by means of a spraying or sputtering process.
  • the desired and predetermined shape of the ignition bridge 11 is applied either by positive or negative contact copying procedures to the pretreated electrodes 9 and transferred to the lightsensitive coating of the electrodes 9 by appropriate developing methods.
  • the electrodes 9 illustrated in FIGS. 3a, 3b and 5a, 5b are shaped essentially in the form of circular segments, for example of platinum silver. Since the primer element shown in FIG. 3a is provided with a bore 10, a layer of platinum silver is likewise arranged around this bore; however, this layer does not have any connection with the electrodes 9.
  • the ignition bridge 11 is disposed between the layer around the bore 10 and an electrode 9, and in the example of FIG.
  • the bridge is arranged between the two electrodes 9.
  • the ignition bridge 11 consisting of tantalum or tantalum nitride, is enlarged at the contact surface with the electrodes 9, so that it covers part of the electrodes 9.
  • the overlapping portions 14 serve for the purpose of establishing as good a contact as possible with the electrodes.
  • an ignition bridge 11 is obtained at a predetermined place, the ignition sensitivty of which is determined by the layer thickness, length, and width of the transition between the contact surfaces and can be measured by the electric resistance thereof.
  • the conductive bridge preferably exhibits a width and a length of 50 u, and a thickness of 0.1 1.5 a.
  • an electrical detonator element including a pole piece and a housing means forming a pair of electrical leads, a primer composition and an ignition bridge element disposed with said primer composition between said pole piece and said housing means, said ignition bridge element comprising an insulating body having first electrode means arranged on at least a first surface of said body for electrically contacting said pole piece and second electrode means arranged on a second surface of said body for electrically contacting said housing means, each of said first and second electrode means including an electrode member formed on said second surface of said body, and a bridge member of a size providing a specific electrical resistance interconnecting said first and second electrode means, said bridge member being provided as a plated metal layer on said second surface of said body in overlapping relationship with portions of each of said electrode members.
  • said insulating body is formed as a round disc having a bore therethrough
  • said first electrode means includes a conductive layer provided on the first surface of said body in contact with said pole piece and a metal portion plated on the surface of said bore electrically interconnecting said conductive layer on said first surface with said electrode member of said first electrode means on said second surface of said body.
  • An electrical detonator element according to claim 1, wherein said insulating body is formed as a round disc, said first electrode means including a conductive layer on said first surface of said body contacting said pole piece and means for connecting said conductive layer to said electrode member of said first electrode means on said second surface of said body.
  • An electrical detonator element according to claim 1 said bridge member having a width and a length of 50 p. and a thickness of 0.1 1.5 p
  • Electrodes 13 are formed of a conductive material selected from the group consisting of nickel, palladium, palladium silver alloy, palladium gold, platinum gold, platinum silver, or a silveraluminum alloy.
  • said bridge member consists of a metal selected from the group consisting of tantalum and tantalum nitride.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Spark Plugs (AREA)
  • Air Bags (AREA)
US00137464A 1970-04-24 1971-04-26 Metal layer initiator Expired - Lifetime US3763782A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2020016A DE2020016C3 (de) 1970-04-24 1970-04-24 Metallschichtzündmittel

Publications (1)

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US3763782A true US3763782A (en) 1973-10-09

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US00137464A Expired - Lifetime US3763782A (en) 1970-04-24 1971-04-26 Metal layer initiator

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US (1) US3763782A (enrdf_load_stackoverflow)
DE (1) DE2020016C3 (enrdf_load_stackoverflow)
FR (1) FR2090579A5 (enrdf_load_stackoverflow)
GB (1) GB1344922A (enrdf_load_stackoverflow)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3440660A1 (de) * 1983-11-09 1985-07-25 Dynamit Nobel Ag, 5210 Troisdorf Elektrisches zuendmittel
US4644863A (en) * 1983-11-09 1987-02-24 Dynamit Nobel Aktiengesellschaft Electric detonator
US4770099A (en) * 1976-10-23 1988-09-13 Dynamit Nobel Ag Propellant charge igniter
US4881463A (en) * 1988-02-24 1989-11-21 The State Of Israel, Ministry Of Defence, Israel Military Industries Electric igniter assembly
WO1994019661A1 (en) * 1993-02-26 1994-09-01 Quantic Industries, Inc. Improved semiconductor bridge explosive device
US5433147A (en) * 1993-03-12 1995-07-18 Dynamit Nobel Aktiengesellschaft Ignition device
US5495806A (en) * 1993-05-28 1996-03-05 Altech Industries (Proprietary) Limited Detonators
WO1996024024A1 (en) * 1995-01-31 1996-08-08 Quantic Industries, Inc. Improved semiconductor bridge explosive device
WO1998010236A1 (en) * 1996-09-03 1998-03-12 Teledyne Industries, Inc. Thin film bridge initiators and method of manufacture
US6054760A (en) * 1996-12-23 2000-04-25 Scb Technologies Inc. Surface-connectable semiconductor bridge elements and devices including the same
US6133146A (en) * 1996-05-09 2000-10-17 Scb Technologies, Inc. Semiconductor bridge device and method of making the same
US6199484B1 (en) * 1997-01-06 2001-03-13 The Ensign-Bickford Company Voltage-protected semiconductor bridge igniter elements
WO2002057705A2 (en) 2001-01-22 2002-07-25 Smi Technology (Pty) Limited An initiating device for an electronic detonator
US7055434B1 (en) * 2003-03-04 2006-06-06 The United States Of America As Represented By The Secretary Of The Navy Electrical initiation system
WO2012108931A1 (en) * 2011-02-07 2012-08-16 Raytheon Company Shock hardened initiator and initiator assembly

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2245308C3 (de) * 1972-09-15 1981-05-07 Dynamit Nobel Ag, 5210 Troisdorf Elektrisches Brückenzündmittel
DE2328184C3 (de) * 1973-06-02 1981-06-25 Dynamit Nobel Ag, 5210 Troisdorf Elektrisch zu zündendes Schaltelement für Stifteinzug
DE2654087C3 (de) * 1976-11-29 1981-07-16 Dynamit Nobel Ag, 5210 Troisdorf Elektrisches Zündmittel
SE431681B (sv) * 1977-04-19 1984-02-20 Bofors Ab Eltenddon
DE2747163A1 (de) * 1977-10-20 1979-04-26 Dynamit Nobel Ag Elektrisches anzuendelement
DE3024554C2 (de) * 1980-06-28 1985-06-05 Dynamit Nobel Ag, 5210 Troisdorf Anordnung zur kontaktlosen Übertragung elektrischer Energie auf Flugkörper bei deren Abschuß
DE3035932A1 (de) * 1980-09-24 1982-05-06 Dynamit Nobel Ag, 5210 Troisdorf Elektrisches zuendmittel
FR2513751B1 (fr) * 1981-09-28 1986-04-11 France Etat Initiateur pyrotechnique electrique a effet joule
DE3231369C1 (de) * 1982-08-24 1984-01-05 Dynamit Nobel Ag, 5210 Troisdorf Sekundaerspule fuer induktive Anzuendmittel
DE3245187A1 (de) * 1982-12-07 1984-06-07 Dynamit Nobel Ag, 5210 Troisdorf Kontaktierung von traegerelementen in elektrischen zuendmitteln
FR2538099B1 (fr) * 1982-12-15 1986-10-03 France Etat Amorce electrique a element resistif
EP0120176B1 (de) * 1983-02-22 1987-11-19 Ems-Inventa AG Elektrischer Polkörper
EP0143071A1 (de) * 1983-11-18 1985-05-29 Fela E. Uhlmann Aktiengesellschaft für gedruckte Schaltungen Verfahren zur Herstellung einer elektrischen Zündvorrichtung, danach hergestellte Zündvorrichtung und deren Verwendung
DE3415625A1 (de) * 1984-04-26 1985-10-31 Dynamit Nobel Ag, 5210 Troisdorf Elektrisches zuendelement mit soll-funkenstrecke
ZA852777B (en) * 1984-05-24 1985-11-27 Inventa Ag Pole body for an electric fuze,method of manufacturing and method of using the pole body
DE3702241C1 (de) * 1987-01-27 1996-06-20 Daimler Benz Aerospace Ag Verfahren und Einrichtung zur Herstellung von Primärzündsätzen, insbesondere Brückenzündern und Spaltzündern
DE4222223C1 (de) * 1992-07-07 1994-03-17 Dynamit Nobel Ag Elektrische Anzünd-/Zündmittel
FR2704944B1 (fr) * 1993-05-05 1995-08-04 Ncs Pyrotechnie Technologies Initiateur électro-pyrotechnique.
FR2746461B1 (fr) * 1996-03-21 1998-05-29 Dixi Fresard Microtechniques Dispositif pour la fixation traversante d'un corps axial dans un support
AT405591B (de) * 1997-10-03 1999-09-27 Schaffler & Co Heizelement und verfahren zu dessen herstellung
AU778545B2 (en) * 1998-12-21 2004-12-09 Orica Explosives Technology Pty Ltd A detonation initiating device
AT413150B (de) 2003-01-28 2005-11-15 Hirtenberger Schaffler Automot Heizelement zum zünden pyrotechnischer ladungen

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2974591A (en) * 1957-04-04 1961-03-14 Wasag Chemie Ag Fa Electric fuses for detonators and the like
US3295446A (en) * 1964-03-12 1967-01-03 Rheinmetall Gmbh Electric primer
US3420174A (en) * 1967-09-29 1969-01-07 Us Navy Pulse sensitive electro-explosive device
US3557699A (en) * 1968-06-26 1971-01-26 Olin Mathieson Electroexplosive primer ignition assembly

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2974591A (en) * 1957-04-04 1961-03-14 Wasag Chemie Ag Fa Electric fuses for detonators and the like
US3295446A (en) * 1964-03-12 1967-01-03 Rheinmetall Gmbh Electric primer
US3420174A (en) * 1967-09-29 1969-01-07 Us Navy Pulse sensitive electro-explosive device
US3557699A (en) * 1968-06-26 1971-01-26 Olin Mathieson Electroexplosive primer ignition assembly

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4770099A (en) * 1976-10-23 1988-09-13 Dynamit Nobel Ag Propellant charge igniter
US4644863A (en) * 1983-11-09 1987-02-24 Dynamit Nobel Aktiengesellschaft Electric detonator
DE3440660A1 (de) * 1983-11-09 1985-07-25 Dynamit Nobel Ag, 5210 Troisdorf Elektrisches zuendmittel
US4881463A (en) * 1988-02-24 1989-11-21 The State Of Israel, Ministry Of Defence, Israel Military Industries Electric igniter assembly
US5912427A (en) * 1993-02-26 1999-06-15 Quantic Industries, Inc. Semiconductor bridge explosive device
WO1994019661A1 (en) * 1993-02-26 1994-09-01 Quantic Industries, Inc. Improved semiconductor bridge explosive device
JP3484517B2 (ja) 1993-02-26 2004-01-06 エヌ・ケイ・エヌ・エム・リミテッド 改良された半導体ブリッジ起爆装置
US5433147A (en) * 1993-03-12 1995-07-18 Dynamit Nobel Aktiengesellschaft Ignition device
US5495806A (en) * 1993-05-28 1996-03-05 Altech Industries (Proprietary) Limited Detonators
WO1996024024A1 (en) * 1995-01-31 1996-08-08 Quantic Industries, Inc. Improved semiconductor bridge explosive device
US6133146A (en) * 1996-05-09 2000-10-17 Scb Technologies, Inc. Semiconductor bridge device and method of making the same
US5732634A (en) * 1996-09-03 1998-03-31 Teledyne Industries, Inc. Thin film bridge initiators and method of manufacture
WO1998010236A1 (en) * 1996-09-03 1998-03-12 Teledyne Industries, Inc. Thin film bridge initiators and method of manufacture
US6054760A (en) * 1996-12-23 2000-04-25 Scb Technologies Inc. Surface-connectable semiconductor bridge elements and devices including the same
US6199484B1 (en) * 1997-01-06 2001-03-13 The Ensign-Bickford Company Voltage-protected semiconductor bridge igniter elements
WO2000079210A3 (en) * 1999-06-15 2001-04-19 Ensign Bickford Co Voltage-protected semiconductor bridge igniter elements
WO2002057705A2 (en) 2001-01-22 2002-07-25 Smi Technology (Pty) Limited An initiating device for an electronic detonator
US7055434B1 (en) * 2003-03-04 2006-06-06 The United States Of America As Represented By The Secretary Of The Navy Electrical initiation system
WO2012108931A1 (en) * 2011-02-07 2012-08-16 Raytheon Company Shock hardened initiator and initiator assembly
US8701557B2 (en) 2011-02-07 2014-04-22 Raytheon Company Shock hardened initiator and initiator assembly
US9816790B2 (en) 2011-02-07 2017-11-14 Raytheon Company Shock hardened initiator and initiator assembly
US9879951B2 (en) 2011-02-07 2018-01-30 Raytheon Company Shock hardened initiator and initiator assembly

Also Published As

Publication number Publication date
GB1344922A (en) 1974-01-23
DE2020016B2 (de) 1974-04-11
DE2020016C3 (de) 1974-12-12
FR2090579A5 (enrdf_load_stackoverflow) 1972-01-14
DE2020016A1 (de) 1971-11-11

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