GB2177483A

GB2177483A - Interconnecting low energy fuses

Info

Publication number: GB2177483A
Application number: GB08613819A
Authority: GB
Inventors: Jean Luc Curutchet; Wayne Guy Fensham
Original assignee: AECI Ltd
Current assignee: AECI Ltd
Priority date: 1985-06-28
Filing date: 1986-06-06
Publication date: 1987-01-21
Anticipated expiration: 2006-06-06
Also published as: ES556733A0; NO165362C; MW4786A1; NO862375D0; AU590576B2; EP0208416A1; ATE41998T1; GB8613819D0; NO862375L; ZW12186A1; ES8704629A1; ZM6086A1; GB2177483B; AU5859086A; NZ216541A; EP0208416B1; BR8602961A; DE3662727D1; NO165362B

Abstract

A connector 100 for interconnecting two lengths of low energy fuse 108, 110 includes connecting means 101 having a needle-like portion 102. The needle-like portion 102 is pointed at both ends 104, 106 to facilitate the penetration of the ends 104, 106 into the lengths of fuse 108 and 110 respectively. The connector 100 further includes a body 112 which defines seats 114 on which regions of the lengths of fuse 108, 110 can seat to be retained in position relative to the connecting means 101. End caps 116 are provided to clip into the body 112 to retain the lengths of fuse 108, 110 on the seats 114.

Description

1 0 p GB 2 177 483 A 1

SPECIFICATION

Interconnecting low energy fuses This invention relates to the interconnecting of low 70 energy fuses, in particular low energy fuses such as that known by the trademark "NONEU.

Low energy fuses of this type comprise plastics tubing containing a suitable explosive material.

According to one aspect of the invention,there is provided a connectorfor interconnecting at leasttwo lengths of lowenergyfuse of thetype described,for transferring a shockwavefront of an explosion prop agating along one length of fuseto the other length of fuse which includes a hollow tubular connecting meanswhich definesa passage and which is insertable into the lengths of fuse so thatthe interior of a first length of fuse is in flow communication with the interior of a second length of fusevia the passage of the connecting 85 means; and a retaining meansfor retaining the connecting means in position relativeto the lengths of fuse.

Itwill be appreciated thattwo ormore lengths of fuse maybe interconnected. Thus, the connecting means may havetwo or more end portions, depen dent on the numberof lengths of tubing thatareto be interconnected.

The connecting means may include at leastone needle-like portion having a pointed end for piercing a wall of at least one of the lengths of fuse.

In one embodiment of the invention, the needle-like portion may have a second end remote from the pointed end, which second end is fast with the retain ing means, the pointed end of the need le-1 ike portion being insertable through the walls of the two lengths of fuse when the lengths of fuse are arranged adja cent one another with their longitudinal axes parallel to one another.

In another embodiment of the invention the needle like portion may have a second end that is also pointed, so that one of the pointed ends of the needle like portion is insertable through the wall of one of the lengths of fuse and the other pointed end of the nee die-like portion is insertable through the wall of the other length of fuse, the lengths of fuse being spaced from each other, in use.

The passage of the connecting means, may, if de sired, contain a primary and/ora secondary explo sive. The passage may also contain a pyrotechnic delay.

The retaining means may comprise a body defining at least one seat in which a connecting region of at least one of the lengths of fuse is receivable for se curely retaining the connecting means in position relative to the length of fuse.

The retaining means may further comprise at least one end cap which is releasably engageable with the body.

In one form of the connector a chamber may be defined in the body and the needle-like portion of the connecting means may comprise two hollow ele ments, each having a pointed end and each project ing from the chamber, the pointed end of one element projecting out of the seat defined by the body and the 130 pointed end of the other element projecting out of another seat defined by the body.

The lengths of fuse may be interconnected with one another intermediate their ends. Instead, the end of one length of fuse may be interconnected with another length of fuse intermediate its ends, in a "T"-configu ration. With this arrangement, one end portion of a connecting meansthat is received within an end of thefuse will be co-linear therewith and the other end portion of the connecting means will be inserted into the other length of fuse in a transverse manner. Further, if two lengths of fuse are to be interconnected with one another intermediate theirends then the end portions of the connecting means will be transversely located with respectto the lengths of fuse. Itwill also be understood thattwo lengths of fuse may be interconnected intermediate their ends with the lengths of fuse being either parallel, ortransverse.

Those skilled in the artwill appreciate that there will not be any problem in inserting an end portion of the connecting means into an end of the fuse. However, if the end portion of the connecting means is to be inserted into the length of fuse intermediate its ends then the end portion must pass through a wall of the fuse so that an opening into the end portion is located within the length of fuse. This may be accomplished by eitherfirst forming a hole in thewall of the fuse and then inserting the end portion, or by adapting the end portion so that itforms a hole as it is inserted through the wall of the fuse. The pointed end of the connecting means may provide an angled opening, the angled opening facing in a suitable direction. Thus, it may face transversely with respectto the length of fuse or longitudinally.

The invention is now described, byway of examples, with referenceto the accompanying drawings, inwhich:- Figure 1 shows a schematic sectioned view of two lengths of fuse interconnected intermediate their ends by means of a connector in accordance with a first embodiment of the invention; Figure2 shows a sectional side view of the connectortaken along line 1111 in Figure 1; Figure3 shows a sectional end view of the connectortaken along line 111- 111 in Figure 1; Figure4shows schematically howtwo lengths of fuse are interconnected in a "T"-conf ig u ration, in accorclancewith another embodiment of the inven- tion.

Figure 5shows a sectional side view of a connector in accordancewith a further embodiment of the invention; Figure 6shows a sectional side view of yetanother embodiment of a connector in accorclancewith the invention: and Figure 7shows a sectional side elevation of still a further embodiment of a connector in accordance with the invention.

Referring to Figures 1 to 3, a connector in accordance with the invention for connecting at leasttwo lengths of low energy fuse fortransferring a shock wavefront of an explosion propagating along one length of fuse to the other length of fuse is designated generally bythe reference numeral 10. The connector 2 GB 2 177 483 A 2 is used for interconnecting two lengths of fuse 12 and 14. Eachfuse 12,14 comprises a length of tubing 16 having its innerwalls coated with an explosive powdertoform a lowenergyfuse such asthat known 5 bythetrade mark"NONEL".

The connector 10 comprisesa hollowtubularconnecting means 18 which is pointed at both ends 20 and 22. Secured to the connecting means 18 intermediate its ends is a collar 24 made of a plastics material.

The collar 24 has abutment shoulders 26 on each side. Secured to the collar 24 and extending past and around the pointed ends 20 and 22 are two clips 28 and 30 which are formed integrally with the collar 24. The clips 28 and 30 togetherwith the abutment shoul- ders 26 of the collar 24 define seats 32 forsecurely retaining the length of tubing 16 in position relativeto the connecting means 18.

The clips 28 and 30 are made of a suitably resilient material so thatthey can be bent back, the fuses 12 and 14 can be engaged with the ends 20 and 22 of the connecting means 18 so that the ends 20 and 22 pierce the tubing 16 of the fuses 12 and 14 respectivelyto extend into the tubing 16. The clips 28 and 30 can then be released to engage with the tubing 16 of the fuses 12 and 14to secure them to the connecting means 18.

Referring nowto Figure 4 another embodiment of the invention isshown. In this embodiment of the invention,two lengths offuse40and42 areinterconnected byrneans of a connector 44 which comprisesa short length of metal tube. As shown, the lengthsof tubing 40 and 42 are interconnected in a "T"configuration with one end of the tube 44 longitudinallyengaging an end of the fuse 40 and the otherend portion of thetube 44 being inserted through a wall of the length of fuse 44 intermediate its ends in atransverse manner. The connector44 includes an outwardly extending flange 45 defining a shoulder against which the end of the length of fuse 40 can abut.

Referring nowto Figure 5 yet another embodiment 105 of the invention is shown. In this embodiment of the invention, a connector in accordance with the inven tion is designated generally bythe reference numeral 50. The connector 50 comprises a connecting means 51 having a needle-like portion which is constituted bytwo elements 52 and 54, each having a pointed end portion 56 and 58 respectively. The elements 52 and 54 project parallel to each otherfrom a chamber60. The chamber 60 is defined bya body 62 of a retaining means 64. The chamber 60 contains a primaryand/or a secondary explosive and, if desired, can also contain a pyrotechnic delay. The body 62 defines seats 66 within which regions of lengths of fuse 68 and 70 of thetype described can seat. The lengths of fuse 68 and 70 are retained in position on the seats 66 of the body 62 by means of an end cap 72 which engages the body portion 62 and is clipped into position.

Referring to Figure 6 yet a further embodiment of a connector in accordance with the invention is shown, the connector being designated generally by reference numeral 80. In this embodiment, the connector comprises a hollowtubular connecting means 82 having a needle-like portion 84. The needle-like portion 84 has a pointed end 86for piercing thewalls of two lengths of fuse 88 and 90 which lie adjacentone another so thattheir longitudinal axes are parallel to each other.

The needle-like portion 84 includes a second end 92 remote from the pointed end 86. The second end 92 is fastwith a retaining means 94 of the connector80. The connecting means 82 defines a passage 96 so thatthe interior of the length of fuse 88 is inflow communication with the interior of the length of fuse 90 when the needle-like portion has been inserted through the lengths of fuse 88 and 90.

Referring nowto Figure 7, still a further embodiment of the invention is shown, the connector being designated generally by the reference numeral 100. The connector 100 comprises a connecting means 101 having a needle-like portion 102. Both ends 104 and 106 of the needle- like portion 102 are pointed to facilitate the penetration of the connecting means 101 into two lengths of fuse 108 and 110 respectively. The connector 100 further includes a retaining means in the form of a body 112 which defines seats 114 on which the lengths of fuses 108 and 110 can seat. The ends 104 and 106 of the needle-like portion 102 projectfrom the seats 114. The connector 100 further includes end caps 116 which clip into the body 112 to retain the lengths of fuses 108 and 110 in position relative to the needle-like portion 102.

Typically, the connecting means of the various embodiments described above can have an outside diameter of about 1 mm and a length ranging from about 15 mm to 25 mm. The angle of the pointed end of the connecting means of the various embodiments should be about 45'and ideally, should facetowards an oncoming shockwave front of an explosion propagating down a length of fuse.

By means of the invention low energyfuses may be interconnected in a simple, effective and reliable manner.

Claims

1. A connectorfor interconnecting at leasttwo lengths of low energy fuse of the type described, for transferring a shockwave front of an explosion propagating along one length of fuse to the other length of fuse which includes a hollow tubular connecting means which defines a passage and which is insertable into the lengths of fuse so thatthe interior of a first length of fuse is in flow communication with the interior of a second length of fuse via the passage of the connecting means; and a retaining meansfor retaining theconnecting means in position relativetothe lengths of fuse.

2. A connector as claimed in Claim 1, in which the passage of said connecting means contains a primary and/or a secondary explosive.

3. A connector as claimed in Claim 2 in which the said passage contains a pyrotechnic delay.

4. A connector as claimed in any of the preceding claims in which the connecting means includes at leastone needle-like portion having a pointed endfor piercing awall of at least one of the lengths offuse.

5. A connector as claimed in Claim 4, in which the needle-like portion has a second end remote from the pointed end, which second end is fastwith the retain- 3 0 10 GB 2 177 483 A 3 ing means,the pointed end of the needle-like portion being insertable through thewalls of thetwo lengths of fusewhen the lengths of fuse are arranged adjacent one anotherwith their longitudinal axes parallel 5 tooneanother.

6. A connector as claimed in Claim 4, in which the needle-like portion has a second end that is also pointed, so that one of the pointed ends of the needlelike portion is insertable through the wall of one of the lengths of fuse and the other pointed end of the needie-like portion is insertable through the wall of the other length of fuse, the lengths of fuse being spaced from each other, in use.

7. A connector as claimed in anyone of Claims 4 to 6 inclusive in which the retaining means comprises a body defining at least one seat in which a connecting region of at least one of the lengths of fuse is receivable for securely retaining the connecting means in position relative to the length of fuse.

8. A connector as claimed in Claim 7, in which the retaining means further comprises at least one end cap which is releasably engageable with the body.

9. Aconnector as claimed in Claim 7 or Claim 8 in which a chamber is defined in the body and.in which the needle-like portion of the connecting means cornprises two hollow elements, each having a pointed end and each projecting from the chamber, the pointed end of one element projecting out of the seat defined by the body and the pointed end of the other element projecting out of another seat defined by the body.

10. A method of transferring a shockwave front of an explosion propagating along a first length of low energy fuse to a second length of low energyfuse which includes Interconnecting the respective lengths of fuse by means of a hollowtubular connecting means defining a passage, so thatthe shockwavefront can propagate through the passage of the connecting means into the second length of fuse.

11. The method as claimed in Claim 10 which includes retaining the connecting means in position relative to the lengths of fuse byway of a retaining means.

12. A connectorfor interconnecting at leasttwo lengths of low energy fuse substantially as described and as illustrated herein.

13. A method of transferring a shock wave front propagating along a first length of low energy fuse to a second length of low energy fuse substantially as described herein.

Printed for Her Majesty's Stationery Office by Croydon Printing Company (1.1 K) Ltd, 11186, D8817356. Published by The Patent Office, 25 Southampton Buildings, London, WC2A l AY, from which copies maybe obtained.