The Ensign-bickford Company

Ronald M Dufrane

Ernest L Gladden

Daniel P Sutula, Jr

Daniel A Toro

Lyman G Bahr

Brendan M Welch

Ronald D Thomas

Thomas C Tseka

Thomas F Lilley, Jr

Robert G Pallanck

Steven L Renfro

Frank J Lucca

Jeffrey H Burton

A detonator (10) is equipped with an input lead (29) having multiple signal transmission lines (30, 31) which provide redundant initiation signals to the target charge (14) of a detonator (10, 10') thereby increasing the reliability of initiation. The multiple signal transmission lines (30, 31) may be made of shock tube and can be part of a long or short input lead (29, 129) and may be initiated by any suitable means, for example by being disposed in signal transmission relation to a detonating cord (60, 62) to improve the reliability with which a signal is transferred from the detonating cord (60, 62) to the detonator (10, 10').

Detonators having multiple-line input leads

A method and apparatus for transferring non-electric blasting initiation signals from detonating cord signal donor lines to signal transmission tube acceptor lines involves disposing the acceptor line in enhanced signal transfer configuration with the donor line. The acceptor line (30) may constitute the input lead (29a) of a detonator (10a). Enhanced signal transfer configuration between the input lead (29a) and the detonating cord (60) can be established by disposing input line (30) in at least partial wrap-around contact with the detonating cord (60) or in multiple abutting contact with the detonating cord (60). Enhanced signal transfer configuration can also be achieved for a detonator having at least two input lines in abutting contact with the detonating cord. A slider (44) is designed to extend contact between a detonator input lead and a detonating cord. The slider (44) provides a detonator retainer (48) for holding a detonator (10a) and a base fixture (74') that includes a pass-through aperture (58a) for a detonating cord (62). Input lead-retaining means (52) on the base fixture (74') disposes the input lead (29a) in position for enhanced signal transfer configuration with a detonating cord that may extend through the pass-through aperture (58a).

Method and apparatus for transfer of initiation signals

A connector device (10, 214) for transferring a nonelectric blast initiation signal from a donor line (26, 224) to an acceptor line, e.g., an input stub (24, 217) has donor line retaining means (20a, 20b, 229) for disposing a donor line (26, 224) in signal transfer relation to the input stub (24, 217). An anvil member (27, 130, 226) is provided to support input stub (24, 217) at the point where it is in signal transfer relation with the donor line (26), preferably in conforming contact with the donor line (26). In a particular embodiment, the connector device has a body portion (10a) on which is retained a detonator cap (22). Cap (22) detonates upon receipt of a detonation signal from an input stub (24), optionally after a delay period if delay elements are incorporated into the cap 22. The connector device (10) has retainer spring clips (20a, 20b) for retaining the donor line (26) in signal transfer relation to the input stub (24). An output line retaining member (16) holds the output line (28) in signal transfer relation to the detonator cap (22).

Connector for blast initiation system

A slider (36) has a base fixture (40) and a shielding tube (42). The slider (36) is used to operably couple a detonator (44) to a detonating cord (62) that passes through a booster device (10), i.e., to prevent the detonating cord (62) from directly initiating or fracturing the booster (10). The base fixture (40) includes input lead-retaining means for disposing the input lead (47) of a detonator (44) in signal transfer relation to the detonating cord (62). Optionally, the slider (36) has a detonator retainer (38) for carrying the detonator (44) on the slider (36). Preferably, the detonator retainer (38) is able to hold detonators of various lengths in proper position to initiate the booster device (10). By disposing the shielding tube (42) on the slider (36) a booster device (10) can be used with various detonating cords (62) and a slider (36) having a shielding tube (42) suitable for the chosen detonating cord (62) can be inserted into the booster device (10).

Slider member for booster explosive charges

A delay train ignition buffer (45) is positioned between a transmission tube (11) and a delay train (25) in a detonator housing (15) or a signal transmission tube housing. The buffer controls the rate at which the transmission tube temperature/pressure pulse is applied to the delay train pyrotechnic surface, attenuating the effects of the pulse with a resulting improvement in delay timing precision. The buffer also attenuates the effects of sudden depressurization within the detonator resulting from the rupture of the transmission tube or ejection of the tube from the housing, thereby preventing separation of the reacting pyrotechnic which could otherwise cause the reaction to cease at the point of separation, thus causing failure of the delay train to continue combustion of the pyrotechnic through its length.

Growing community of inventors

North Granby, CT, United States of America

Ronald M Dufrane