Brendan J Walsh

US Patent:

6408759, Jun 25, 2002

Filed:

Feb 29, 2000

Appl. No.:

09/402868

Inventors:

David W. Ewick - North Granby CT
Brendan M. Walsh - Simsbury CT

Assignee:

The Ensign-Bickford Company - Simsbury CT

International Classification:

F42B 310

US Classification:

1022025, 1022755

Abstract:

An initiator ( ) assembled from a housing ( ), an output charge ( ) and an initiation means ( ) includes a pulverulent ignition charge ( ) disposed in direct initiation relation to the initiation means, and an output charge ( ) that may contain a pulverulent deflagration-to-detonation transition (DDT) charge ( ) and an explosive base charge ( ). The ignition charge ( ) has an average particle size of less than 10 microns, or even less than 5 microns, e. g. , 1 to 2 microns. The initiation means may include a semiconductor bridge ( ) and the ignition charge ( ) may be compacted with a force of less than about 5880 psi, e. g. , with a force of 1000 psi. In another embodiment, an initiator ( ) includes a low-energy electrical initiator ( ), a loosely packed BNCP ignition charge ( ) and a pyrotechnical output charge ( ).

US Patent:

58892281, Mar 30, 1999

Filed:

Apr 9, 1997

Appl. No.:

8/831664

Inventors:

David W. Ewick - North Granby CT
Brendan M. Walsh - Simsbury CT

Assignee:

The Ensign-Bickford Company - Simsbury CT

International Classification:

C06C 500
F42B 310

US Classification:

1022755

Abstract:

A detonator (100) assembled from a housing (112), an output charge (144) and an initiation means (110, 120, 58, 54) includes a pulverulent ignition charge (46a) disposed in direct initiation relation to the initiation means, and an output charge (144) that may contain a pulverulent deflagration-to-detonation transition (DDT) charge (144a) and a base charge (144b). The ignition charge (46a) has an average particle size of less than 10 microns, or even less than 5 microns, e. g. , 1 to 2 microns. The initiation means may include a semiconductor bridge (18) and the ignition charge (46a) may be compacted with a force of less than about 5880 psi, e. g. , with a force of 1000 psi.

US Patent:

54600936, Oct 24, 1995

Filed:

Aug 2, 1993

Appl. No.:

8/101237

Inventors:

Francois Prinz - San Jose CA
Kent Steeves - Newark DE
Peter L. C. Atkeson - Newark DE
Brendan Walsh - Elkton MD
J. Michael Wilson - Gilroy CA

Assignee:

Thiokol Corporation - Ogden UT

International Classification:

F42D 1055

US Classification:

102217

Abstract:

A programmable electronic time delay initiator includes a digital time-delay circuit that counts in response to a dual-resonator clock and, at the end of the programmed time delay, gates the pre-stored charge on a capacitor to a semiconductor bridge initiator to fire an explosive. The timer circuit includes a combined crystal/RC oscillator that provides high accuracy oscillations from the crystal or oscillations from the RC components in the event the crystal fails. The timer circuit functions in response to multi-part serial commands delivered on a conventional two-wire path. The timer is initially powered-on to provide power to a capacitor that supplies power to the time-delay and related circuits. An initial ATTENTION pulse initializes the circuitry and starts a watchdog timer that counts a fixed number of clock cycles and resets the logic if a following WRITE, ARM, or FIRE command is not received. A WRITE pulse and following programming pulses programs a fusible link memory with time-delay information, an ARM pulse effects charging of a firing-charge capacitor, and a FIRE pulse gates the firing-charge to the bridge initiator to fire the explosive.

US Patent:

59293683, Jul 27, 1999

Filed:

Dec 9, 1996

Appl. No.:

8/762262

Inventors:

David W. Ewick - North Granby CT
Paul N. Marshall - Avon CT
Kenneth A. Rode - Granby CT
Thomas C. Tseka - West Suffield CT
Brendan M. Walsh - Simsbury CT

Assignee:

The Ensign-Bickford Company - Simsbury CT

International Classification:

H03K 17687
H03K 17567
F42D 1055

US Classification:

102215

Abstract:

An electronic delay circuit (10) for use in a detonator (100) has a switching circuit (20) and a timer circuit (22). Switching circuit (20) controls the flow of a stored charge of electrical energy from a storage capacitor (12) to a bridge initiation element such as a semiconductor bridge (18) or a tungsten bridge. The timing of the release of this energy is controlled by timer circuit (22). Switching circuit (20) is an integrated, dielectrically isolated, bipolar CMOS (DI BiCMOS) circuit, whereas timer circuit (22) is a conventional CMOS circuit. The use of a DI BiCMOS switching circuit allows for greater efficiency of energy transfer from the storage capacitor (12) to the semiconductor bridge (18) than has previously been attained.