Initiation fixture and an initiator assembly including the same

Abstract

An initiator assembly ( 38 ) is factory-pre-assembled and comprises an initiation fixture ( 10 ) secured to a triggering device ( 40 ). The initiation fixture ( 10 ) comprises a unitary body, i.e., one without moving parts, and includes a bushing groove ( 18 ) to receive as an accessory an O-ring ( 64 ) to seal the device within the barrel ( 42 ) of the triggering device ( 40 ). A fuse/fixture sub-assembly ( 34 ) includes an initiation charge ( 30 ) disposed at the firing face ( 13 a ) and a signal-transmission fuse ( 22 ). The initiation fixture ( 110 ) may be a “universal” fixture having thereon optional external threads ( 36 ) and being otherwise dimensioned and configured to be received within either an internally threaded barrel ( 42 ) of a triggering device ( 40 ) or the barrel ( 42 ) of a triggering device which utilizes a fuse-holder cap ( 56 ). The initiator assembly ( 38 ) may include a spool ( 66 ) on which the signal-transmission tube ( 22 ) is wound.

1 . An initiator assembly comprising:
 (a) a triggering device having a barrel comprising an output end and an interior surface, the barrel having disposed therein an internal positioning member and a firing mechanism comprising a firing pin;   (b) an initiation fixture which is of unitary construction whereby no part thereof defined as (i) through (iv) below is movable relative to any other part (i) through (iv) thereof, and the initiation fixture is secured to the triggering device and comprises: (i) a cylindrical body member having an external surface and a nose portion terminating in a firing face, the body member being configured to be received longitudinally within the barrel of the triggering device at the output end thereof, (ii) a longitudinal internal passage extending through the body member, (iii) an external positioning member disposed on the external surface of the body member and engaging the internal positioning member, thereby positioning the body member at a predetermined position within the barrel, and (iv) a well formed in the body member at the firing face thereof and dimensioned and configured to receive an initiation charge, the well being in signal-transfer communication with the longitudinal internal passage; and   (c) a signal-transmission fuse secured to and extending from the body member and having an input end disposed in signal-transfer relation to the initiation charge, and an opposite output end.   
   
   
       2 . The assembly of  claim 1 , wherein the internal positioning member comprises an internal stop and the external positioning member comprises a shoulder which is dimensioned and configured to abut the internal stop. 
   
   
       3 . The assembly of  claim 1  or  claim 11 , wherein the initiation fixture further comprises a sealing member disposed circumferentially about the body member and dimensioned and configured to engage the interior surface of the barrel to form a seal therewith. 
   
   
       4 . The assembly of  claim 1  or  claim 11 , wherein the triggering device further comprises a fuse-holder cap disposed at the output end of the barrel and having therein an aperture through which the signal-transmission fuse passes. 
   
   
       5 . The assembly of  claim 4 , wherein the end face of the body member is dimensioned and configured to be engaged by the fuse-holder cap to retain the body member within the barrel. 
   
   
       6 . The assembly of  claim 1  or  claim 11 , wherein the initiation fixture further comprises a sleeve extending from the end face of the body member and through which the signal-transmission fuse passes. 
   
   
       7 . The assembly of  claim 6 , wherein the triggering device further comprises a fuse-holder cap disposed at the output end of the barrel, and having therein an aperture through which the sleeve of the initiation fixture extends. 
   
   
       8 . The assembly of  claim 1  or  claim 11 , wherein the triggering device is mounted on a spool on which the signal-transmission fuse is wound. 
   
   
       9 . The assembly of  claim 1  or  claim 11 , wherein the output end of the signal-transmission fuse is received within a detonator. 
   
   
       10 . The assembly of  claim 9 , wherein the detonator is positioned within a connector block dimensioned and configured to receive a plurality of signal-transmission lines therein. 
   
   
       11 . An initiator assembly comprising:
 (a) a triggering device having a barrel comprising an output end and an interior surface, the barrel having disposed therein an internal positioning member and a firing mechanism comprising a firing pin;   (b) an initiation fixture which is of unitary construction whereby no part thereof defined as (i) through (iv) below is movable relative to any other part (i) through (iv) thereof, and the initiation fixture is secured to the triggering device and comprises: (i) a cylindrical body member having an external surface and a nose portion terminating in a firing face, the body member being configured to be received longitudinally within the barrel of the triggering device at the output end thereof, (ii) a longitudinal internal passage extending through the body member, (iii) an external positioning member disposed on the external surface of the body member and engaging the internal positioning member, thereby positioning the body member at a predetermined position within the barrel, and (iv) a well formed in the body member at the firing face thereof and in signal-transfer communication with the longitudinal internal passage; and   (c) an initiation charge disposed within the well at the firing face of the body member and exposed to the firing pin of the firing mechanism, and a signal-transmission fuse secured to and extending from the body member and having an input end disposed in signal-transfer relation to the initiation charge, and an opposite output end.