Accession Number:

ADA021906

Title:

A Capacitor Discharge Squib Firing Unit

Descriptive Note:

Corporate Author:

WENTWORTH INST BOSTON MA

Personal Author(s):

• Green, Owen R.

Report Date:

1975-04-01

Pagination or Media Count:

23.0

Abstract:

In 1973, Wentworth Institute WI was asked to produce a practical, reliable, off-the-shelf CD unit for firing standard squibs. Design objectives included simultaneous four-bridgewire firing capability, one-second recovery, 0. 5A supply drain, and three outputs. A 28 VDC supply is required. The Model CD- B is described a 28 volt firing command closes a selected firing relay for 30 ms at 20 ms, the firing capacitors are discharged into the squib circuit through an SCR. The unit includes standard safety features ARMSAFE relay and 100 k-ohm squib isolation, and monitors for both capacitor voltage and squib current. Nine CD units have been built by WI for use in sounding rockets. Four flights have used the CD units for primary squib ignition no malfunctions have been indicated. CD squib current data is shown for eight in-flight firings. This data suggests that a reduction in the size of the CD unit may be possible. The Model CD-B measures 10.2 x 12.7 x 5.7 cm 4 x 5 x 2.25 in. and weighs 0.7 kg 24.7 oz..

Descriptors:

• *CAPACITORS
• *ELECTRIC IGNITERS
• VOLTAGE
• PRIMERS
• ELECTRIC DISCHARGES
• SAFING AND ARMING(ORDNANCE)
• ARMING DEVICES
• FIRING CIRCUITS
• EXPLODING WIRES
• SILICON CONTROLLED RECTIFIERS
• CURRENT LIMITERS

Subject Categories:

• Ammunition and Explosives

Distribution Statement:

APPROVED FOR PUBLIC RELEASE