US3682096A - Electric detonator element - Google Patents

Electric detonator element Download PDF

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Publication number
US3682096A
US3682096A US844823A US3682096DA US3682096A US 3682096 A US3682096 A US 3682096A US 844823 A US844823 A US 844823A US 3682096D A US3682096D A US 3682096DA US 3682096 A US3682096 A US 3682096A
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US
United States
Prior art keywords
housing
carrier
conductive
pole piece
bridge
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US844823A
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English (en)
Inventor
Wolfgang Ludke
Peter Roh
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dynamit Nobel AG
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Dynamit Nobel AG
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Filing date
Publication date
Application filed by Dynamit Nobel AG filed Critical Dynamit Nobel AG
Application granted granted Critical
Publication of US3682096A publication Critical patent/US3682096A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
    • F42C19/00—Details of fuzes
    • F42C19/08—Primers; Detonators
    • F42C19/12—Primers; Detonators electric

Definitions

  • ABSTRACT An electric detonator element in which an incan- V descent bridge, intended to set off a charge, is formed on one side of a non-conductive carrier which is inserted into a conductive housing and rests on its side opposite the bridge, against a center pole electrically connected with the housing by way of the bridge.
  • the present invention relates to an electric detonator element with an electrically conductive housing and a pole piece arranged therein and accessible from the outside, which pole piece is connected with the housing in an electrically conductive manner by way of an incandescent or heater bridge, as well as with an ignitable charge accommodated in the housing and being in operative connection with the incandescent or heater bridge.
  • the incandescent or glow bridge as an extremely thin and very short metallic wire which is connected with the housing or the pole piece, respectively, by soldering or welding.
  • this procedure entails the disadvantage that the manufacturing expense is relatively high since the dimensions of the individual components are very small, and accordingly a large amount of skill and patience is required to carry out completely satisfactorily and flawlessly the welded or soldered connections of the incandescent or heater bridge with the poles.
  • the present invention is based on the aim to simplify the manufacture of the electrical connection between the housing and the pole piece, constructed as a glow or incandescent bridge, and thus simultaneously to make the same also more reliable.
  • the glow or incandescent bridge is formed on the side opposite the pole, of an electrically non-conductive carrier element abutting at the pole piece and together with the same held in the housing by form-locking and/or frictional contact.
  • Such a construction makes it possible to apply the glow or incandescent bridge, independently of the housing and of the pole piece, onto an element which, as compared to the incandescent bridge, is relatively large and correspondingly more easy to handle whereby this element, like the pole piece, can then be inserted simply into the housing and, with a corresponding shape of the housing, can be maintained in secure contact connection with the housing as well as with the pole piece so that the electrically conductive connection between the housing and the pole piece can be established by way of the glow or incandescent bridge by simple contact connections, and accordingly the otherwise required, time-consuming welding or soldering operations, which frequently are carried out not completely satisfactorily, may be completely dispensed with.
  • the housing can be formed, for example, as a sleeve open at both ends which, after insertion of the pole piece and of the carrier element, is together, crimped or flanged over at the ends in such a manner that the individual parts are pressed against one another to a sufiiciently great extent.
  • the carrier element made from an electrically non-conductive material, with a bore disposed, for example, in the center thereof, through which an end of the glow or incandescent bridge is then extended to the side of the carrier element facing the pole piece.
  • Another improvement of the contact connection between the ends of the glow or incandescent bridge and the outer pole or center pole, respectively, can be achieved in accordance with another proposal of the present invention by enlarging the surface area of the glow or incandescent bridge at the ends.
  • the housing, on the end facing the glow or incandescent bridge is formed with a shoulder or ofiset, instead of being simply pressed or flanged over against the glow or incandescent bridge, against which the carrier element can rest in flush contact with one end of the glow or incandescent bridge.
  • the glow or incandescent bridge itself can be formedin a conventional manner, for example, as an extremely thin metallic wire which is held on the carrier element, for instance, by means of an adhesive or bonding material.
  • an essentially more economical and yet more reliable manufacture of the glow or incandescent bridge and the application thereof to the carrier element is possible if according to a further suggestion of the present invention, the glow or incandescent bridge is applied to the carrier element in accordance with the conventional methods for the manufacture of printed electric circuits. This can be done, for example, by applying a metallic foil, possible with the aid of an adhesive, onto a carrier material with the use of pressure and heat.
  • the metallic foil material are, depending on the requirements to be met by the glow or incandescent bridge, for example, copper, silver, gold, nickel, chrome nickel, or also Constantan (an alloy consisting of about percent copper and of about 40 percent nickel), whereas for the carrier material can be used, for example, a molded laminated plastic which consists of cellulose paper, cotton fabric, glass fiber fabric, synthetic fiber fabric, or the like impregnated with a synthetic resin on the basis of phenol, epoxy, or an unsaturated polyester of any known type.
  • the carrier material for example, a molded laminated plastic which consists of cellulose paper, cotton fabric, glass fiber fabric, synthetic fiber fabric, or the like impregnated with a synthetic resin on the basis of phenol, epoxy, or an unsaturated polyester of any known type.
  • the metallic foil is masked with an etch-resistant coating such as varnish or lacquer corresponding to the intended construction of the glow or incandescent bridge, thereupon the metallic foil is removed in the unmasked areas by means of an etching acid, and finally the etch-resistant varnish or lacquer is removed, so that there remains on the molded laminated plastic only a metallic foil pattern corresponding to the desired configuration of the glow or incandescent bridge.
  • an etch-resistant coating such as varnish or lacquer corresponding to the intended construction of the glow or incandescent bridge
  • this glow or incandescent bridge could also be applied directly in the desired configuration to the carrier element by chemical and/or galvanic process, for example according to the Noviganth process of Schering A.G., Berlin, or the Nibodur" process of Wegriken Bayer A.G., Leverkusen.
  • the shape of the glow or incandescent bridge and of the ends thereof formed as contact surfaces can be adapted to the respective requirements in a particularly simple manner, i.e., the glow or incandescent bridge can be constructed, for example, rectilinearly or spirally shaped and the contact surfaces can be constructed, for example, approximately in the shape of a circular disk, of a ring or also of an annular segment.
  • FIG. 1 is a plan view on the carrier element in accordance with the present invention and having a glow or incandescent bridge with an enlarged surface area at the ends thereof;
  • FIG. 2 is a cross sectional view of the carrier element, taken along line AA of FIG. 1;
  • FIG. 3 is a longitudinal axial cross sectional view through an electric detonator of center pole construction with a carrier element inserted therein according to the present invention.
  • the circular-disk-shaped carrier element 1 illustrated in FIGS. 1 and 2 is provided on the topside with a radially extending metallic web of a small thickness and width, forming the glow or incandescent bridge 2, which is enlarged at the outer end thereof into an annular contact surface 3 and whose inner end is extended through a central bore 4 to the circular-disk-shaped contact surface 5 formed on the bottomside of the carrier element 1.
  • connection between the inwardly disposed end of the heater or incandescent bridge 2 and the lower contact surface 5 can thereby be either so constructed that the entire cross section of the bore 4 is filled out, in that for example, a solid rivet is inserted into the bore 4, or as indicated in dashed lines-in that this connection is limited only to a thin layer along the wall of the bore, which can, for example, be applied simultaneously with the other metallic surfaces by galvanic means.
  • the carrier element 1 is inserted with the lower contact surface 5 abutting against pole piece 6 serving as center pole, into a cylindrical housing 7 forming the outer pole whereby the pole piece 6 is supported against the bottom 9 of the housing by way of a cup-shaped electrical insulation 8 and is accessible from the outside by way of central apertures 10, 11 formed in this housing bottom 9 as well as in the insulation 8.
  • a metallic cylindrical sleeve 12 is placed over the carrier element 1, the sleeve, on the one hand, is in electrically conductive connection with the contact surface 3 of the carrier element 1 and, on the other hand, with the housing 7, and is formed, on the end opposite the carrier element 1, with an external annular chamfer 13 against which is pressed the housing after the insertion of the sleeve 12.
  • the ignitable composition or charge 14 is arranged in the sleeve 12 which for the purpose of a completely satisfactory and flawless ignition, should touch the heater or incandescent bridge 2 to the greatest extent possible. This is applicable, in particular, when the conditions are such that the glow or incandescent bridge 2, is brought only to incandescence, but not to an explosive vaporization as a result of the electrical voltage applied to the pole piece 6 and to the housing 7.
  • An electric detonator element having an electrically conductive housing with a pole piece arranged therein so as to be accessible from the outside, which pole piece is electrically connected with the housing by way of incandescent bridge means, and an ignitable charge accommodated in the housing in operative con tact with the bridge means, characterized in that the bridge means is formed on one uniformly planar side of an electrically nonconductive carrier means facing opposite the pole piece, the other side of said carrier means resting against the pole piece and together with said pole piece being retained in the housing, one end of said bridge means being extended to said other side of said carrier means through a bore formed in the car rier means and the other end of said bridge means being connected to an annular conductive member surrounding said bridge means and electrically contacting said housing, said bridge means and said annular conductive member being contiguous plated layers of substantially the same thickness.
  • An electric detonator element according to claim 1 characterized in that said carrier means, together with said pole piece, is retained in said housing by form-locking means.
  • An electric detonator element according to claim 1, characterized in that said carrier means, together with said pole piece, is retained in said housing by frictional contact means.
  • An electric detonator element characterized in that a shoulder is formed in the housing on the side of said carrier means opposite said pole piece by a sleeve means of an electrically conductive material containing at least a portion of the ignitable charge, said sleeve means being inserted into the housing and being connected with the housing in an electrically conductive manner.
  • An electric detonator element characterized in that the bridge means is applied to the carrier means in the manner of a printed electric circuit.
  • An electric detonator element characterized in that the bridge means is applied to the carrier means in the manner of a printed electric circuit.
  • an electric detonator having a conductive housing, a pole piece insulatedly positioned within said housing so as to protrude from one end thereof, a generally annular conductive sleeve positioned in the other end of said housing in conductive contact therewith and an ignitable charge disposed within said annular sleeve
  • incansaid conductive sleeve including an electrically nonconductive carrier having a hole therethrough, first and second concentric conductive rings on one surface of said carrier, said first ring surrounding said hole and being in contact with said ignitable charge, said second ring following the periphery of said carrier and contacting said sleeve, a conductive bridge formed on said one surface of said carrier and interconnecting said first and second rings while contacting said ignitable charge, a conductive disc formed on the other side of said carrier surrounding said hole and contacting said pole piece, and conductive means interconnecting said first ring with said conductive disc through said hole, said first and second rings and said conductive disc

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Air Bags (AREA)
  • Resistance Heating (AREA)
US844823A 1968-07-25 1969-07-25 Electric detonator element Expired - Lifetime US3682096A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19681771889 DE1771889A1 (de) 1968-07-25 1968-07-25 Elektrisches Zuendelement

Publications (1)

Publication Number Publication Date
US3682096A true US3682096A (en) 1972-08-08

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ID=5701025

Family Applications (1)

Application Number Title Priority Date Filing Date
US844823A Expired - Lifetime US3682096A (en) 1968-07-25 1969-07-25 Electric detonator element

Country Status (9)

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US (1) US3682096A (xx)
AT (1) AT286851B (xx)
BE (1) BE736604A (xx)
CH (1) CH496940A (xx)
DE (1) DE1771889A1 (xx)
FR (1) FR2013677A1 (xx)
GB (1) GB1278611A (xx)
NL (1) NL6911388A (xx)
SE (1) SE369959B (xx)

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3867885A (en) * 1972-09-15 1975-02-25 Dynamit Nobel Ag Electrical primer
FR2388246A1 (fr) * 1977-04-19 1978-11-17 Bofors Ab Dispositif d'allumage electrique
US4369707A (en) * 1978-07-12 1983-01-25 Daimler-Benz Aktiengesellschaft Short circuit fuse for electrical igniters
US4378738A (en) * 1979-12-19 1983-04-05 Proctor Paul W Electromagnetic and electrostatic insensitive blasting caps, squibs and detonators
US4525238A (en) * 1982-12-15 1985-06-25 Sfernice Societe Francaise De L'electro-Resistance Process for manufacturing an electric circuit intended for firing a pyrotechnic device and the circuit thus obtained
JPS62269000A (ja) * 1986-05-15 1987-11-21 中国化薬株式会社 雷管の発火方法
US4881463A (en) * 1988-02-24 1989-11-21 The State Of Israel, Ministry Of Defence, Israel Military Industries Electric igniter assembly
US4904196A (en) * 1987-07-17 1990-02-27 Yazaki Corporation Releasable connector for electric circuits
US4976200A (en) * 1988-12-30 1990-12-11 The United States Of America As Represented By The United States Department Of Energy Tungsten bridge for the low energy ignition of explosive and energetic materials
US5204491A (en) * 1990-11-27 1993-04-20 Thomson -- Brandt Armements Pyrotechnic detonator using coaxial connections
US5847309A (en) * 1995-08-24 1998-12-08 Auburn University Radio frequency and electrostatic discharge insensitive electro-explosive devices having non-linear resistances
US5992326A (en) * 1997-01-06 1999-11-30 The Ensign-Bickford Company Voltage-protected semiconductor bridge igniter elements
US6105503A (en) * 1998-03-16 2000-08-22 Auburn University Electro-explosive device with shaped primary charge
EP1036298A1 (en) * 1997-12-11 2000-09-20 Remington Arms Company, Inc. Electric primer
US6199484B1 (en) 1997-01-06 2001-03-13 The Ensign-Bickford Company Voltage-protected semiconductor bridge igniter elements
US6422146B1 (en) * 1999-08-27 2002-07-23 Trw Airbag Systems Gmbh & Co. Kg Igniter unit for an inflator
EP1421328A2 (en) * 2001-08-28 2004-05-26 SCB Technologies, Inc. Tubular igniter bridge
US6772692B2 (en) 2000-05-24 2004-08-10 Lifesparc, Inc. Electro-explosive device with laminate bridge
US20050067071A1 (en) * 2003-09-04 2005-03-31 Hamilton Brian K. Low density slurry bridge mix
US20050066833A1 (en) * 2003-09-04 2005-03-31 Hamilton Brian K. Single pin initiator for a gas generating device
RU2541355C1 (ru) * 2013-08-27 2015-02-10 Российская Федерация, от имени которой выступает Государственная корпорация по атомной энергии "Росатом" Электрическая взрывная сеть
WO2015018828A1 (de) * 2013-08-05 2015-02-12 Ruag Ammotec Gmbh Elektrisches anzündhütchen für kleinkaliber-munition
US10215545B2 (en) * 2013-08-05 2019-02-26 Ruag Ammotec Gmbh Electromechanical primer cap
RU2745086C1 (ru) * 2020-05-12 2021-03-19 Российская Федерация, от имени которой выступает Министерство обороны Российской Федерации Инициатор модульного метательного заряда

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2654087C3 (de) * 1976-11-29 1981-07-16 Dynamit Nobel Ag, 5210 Troisdorf Elektrisches Zündmittel
DE2701373C2 (de) * 1977-01-14 1982-12-23 Dr. Johannes Heidenhain Gmbh, 8225 Traunreut Verfahren zum Herstellen einer Widerstandsschicht von Metallschichtzündmitteln
SE430723B (sv) * 1982-04-30 1983-12-05 Bofors Ab Forfarande och anordning for att astadkomma en veldefinerad och elektriskt ledande brygga mellan tva polkroppar forfarande och anordning for att astadkomma en veldefinerad och elektriskt ledande brygga mellan tva polkroppar
DE3231369C1 (de) * 1982-08-24 1984-01-05 Dynamit Nobel Ag, 5210 Troisdorf Sekundaerspule fuer induktive Anzuendmittel
FR2538099B1 (fr) * 1982-12-15 1986-10-03 France Etat Amorce electrique a element resistif
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

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA581316A (en) * 1959-08-11 Canadian Industries Limited Blasting caps with printed circuit bridge
US2972951A (en) * 1952-05-06 1961-02-28 Richard H Stresau Electric initiator for fuze
US2974591A (en) * 1957-04-04 1961-03-14 Wasag Chemie Ag Fa Electric fuses for detonators and the like
US3196041A (en) * 1960-11-25 1965-07-20 Gen Lab Associates Inc Method of making a semiconductor gap for an initiator
US3426682A (en) * 1967-04-27 1969-02-11 Sidney A Corren Exploding fuse
US3447416A (en) * 1967-09-01 1969-06-03 Us Army Electric initiator

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA581316A (en) * 1959-08-11 Canadian Industries Limited Blasting caps with printed circuit bridge
US2972951A (en) * 1952-05-06 1961-02-28 Richard H Stresau Electric initiator for fuze
US2974591A (en) * 1957-04-04 1961-03-14 Wasag Chemie Ag Fa Electric fuses for detonators and the like
US3196041A (en) * 1960-11-25 1965-07-20 Gen Lab Associates Inc Method of making a semiconductor gap for an initiator
US3426682A (en) * 1967-04-27 1969-02-11 Sidney A Corren Exploding fuse
US3447416A (en) * 1967-09-01 1969-06-03 Us Army Electric initiator

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3867885A (en) * 1972-09-15 1975-02-25 Dynamit Nobel Ag Electrical primer
FR2388246A1 (fr) * 1977-04-19 1978-11-17 Bofors Ab Dispositif d'allumage electrique
US4267567A (en) * 1977-04-19 1981-05-12 Aktiebolaget Bofors Electric igniter
US4369707A (en) * 1978-07-12 1983-01-25 Daimler-Benz Aktiengesellschaft Short circuit fuse for electrical igniters
US4378738A (en) * 1979-12-19 1983-04-05 Proctor Paul W Electromagnetic and electrostatic insensitive blasting caps, squibs and detonators
US4525238A (en) * 1982-12-15 1985-06-25 Sfernice Societe Francaise De L'electro-Resistance Process for manufacturing an electric circuit intended for firing a pyrotechnic device and the circuit thus obtained
JP2501560B2 (ja) * 1986-05-15 1996-05-29 中国化薬株式会社 雷管の発火方法
JPS62269000A (ja) * 1986-05-15 1987-11-21 中国化薬株式会社 雷管の発火方法
US4904196A (en) * 1987-07-17 1990-02-27 Yazaki Corporation Releasable connector for electric circuits
US4881463A (en) * 1988-02-24 1989-11-21 The State Of Israel, Ministry Of Defence, Israel Military Industries Electric igniter assembly
US4976200A (en) * 1988-12-30 1990-12-11 The United States Of America As Represented By The United States Department Of Energy Tungsten bridge for the low energy ignition of explosive and energetic materials
US5204491A (en) * 1990-11-27 1993-04-20 Thomson -- Brandt Armements Pyrotechnic detonator using coaxial connections
US5847309A (en) * 1995-08-24 1998-12-08 Auburn University Radio frequency and electrostatic discharge insensitive electro-explosive devices having non-linear resistances
US5905226A (en) * 1995-08-24 1999-05-18 Auburn University Radio frequency and electrostatic discharge insensitive electro-explosive devices having non-linear resistances
US6272965B1 (en) * 1995-08-24 2001-08-14 Auburn University Method of forming radio frequency and electrostatic discharge insensitive electro-explosive devices
US6199484B1 (en) 1997-01-06 2001-03-13 The Ensign-Bickford Company Voltage-protected semiconductor bridge igniter elements
US5992326A (en) * 1997-01-06 1999-11-30 The Ensign-Bickford Company Voltage-protected semiconductor bridge igniter elements
EP1036298A1 (en) * 1997-12-11 2000-09-20 Remington Arms Company, Inc. Electric primer
EP1036298A4 (en) * 1997-12-11 2003-06-18 Ra Brands Llc ELECTRIC PRIMER
US6105503A (en) * 1998-03-16 2000-08-22 Auburn University Electro-explosive device with shaped primary charge
US6422146B1 (en) * 1999-08-27 2002-07-23 Trw Airbag Systems Gmbh & Co. Kg Igniter unit for an inflator
US6772692B2 (en) 2000-05-24 2004-08-10 Lifesparc, Inc. Electro-explosive device with laminate bridge
US6925938B2 (en) 2000-05-24 2005-08-09 Quantic Industries, Inc. Electro-explosive device with laminate bridge
US20050115435A1 (en) * 2000-05-24 2005-06-02 Baginski Thomas A. Electro-explosive device with laminate bridge
EP1421328A2 (en) * 2001-08-28 2004-05-26 SCB Technologies, Inc. Tubular igniter bridge
EP1421328A4 (en) * 2001-08-28 2008-10-01 Ensign Bickford Aerospace & De TUBE BRIDGE
US6905562B2 (en) 2003-09-04 2005-06-14 Autoliv Asp, Inc. Low density slurry bridge mix
US20050066833A1 (en) * 2003-09-04 2005-03-31 Hamilton Brian K. Single pin initiator for a gas generating device
US20050067071A1 (en) * 2003-09-04 2005-03-31 Hamilton Brian K. Low density slurry bridge mix
WO2015018828A1 (de) * 2013-08-05 2015-02-12 Ruag Ammotec Gmbh Elektrisches anzündhütchen für kleinkaliber-munition
KR101921167B1 (ko) * 2013-08-05 2018-11-22 루아그 암모텍 게엠베하 소구경 탄환용 전기적 점화 캡
US10215545B2 (en) * 2013-08-05 2019-02-26 Ruag Ammotec Gmbh Electromechanical primer cap
US10415944B2 (en) 2013-08-05 2019-09-17 Ruag Ammotec Gmbh Electronic primer cap for small-caliber ammunition
RU2541355C1 (ru) * 2013-08-27 2015-02-10 Российская Федерация, от имени которой выступает Государственная корпорация по атомной энергии "Росатом" Электрическая взрывная сеть
RU2745086C1 (ru) * 2020-05-12 2021-03-19 Российская Федерация, от имени которой выступает Министерство обороны Российской Федерации Инициатор модульного метательного заряда

Also Published As

Publication number Publication date
AT286851B (de) 1970-12-28
FR2013677A1 (xx) 1970-04-03
BE736604A (xx) 1969-12-31
NL6911388A (xx) 1970-01-27
CH496940A (de) 1970-09-30
GB1278611A (en) 1972-06-21
SE369959B (xx) 1974-09-23
DE1771889A1 (de) 1972-01-27

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