EP 0256613 A3 19900816 - IGNITION SYSTEM
Title (en)
IGNITION SYSTEM
Publication
Application
Priority
CA 509201 A 19860515
Abstract (en)
[origin: GB2190552A] The system includes a transformer 15 having a primary winding 17 and a secondary winding 21 which is electromagnetically coupled to the blasting caps via small toroid transformers (49), (Figure 5). On connection to an AC source, A.D.C. power supply 1 charges a capacitor 3 to a predetermined voltage whereupon a sensing circuit 7 operates a latch 9 which turns off the supply 1 and activates a delay circuit 13. After a 30 m.sec delay a 10 KHz oscillator and flip flop circuit 35 is enabled to trigger driver circuits 27,29 alternately thereby producing an A.C. pulse train of decreasing amplitude by periodic discharge of capacitor 3 into the transformer primary 17. Each driver circuit has eight parallel-connected FETs (43), (Figure 2), and the transformer secondary delivers sufficient energy (eg. 950 volts peak, 6 amps average) simultaneously to fire up to 300 blasting caps (55) and allows the conventional inductance-cancelling capacitance in the secondary circuit to be omitted. <IMAGE>
IPC 1-7
IPC 8 full level
F42D 1/05 (2006.01)
CPC (source: EP)
F42D 1/05 (2013.01)
Citation (search report)
- [X] GB 2132041 A 19840627 - TROLEX PROD LTD
- [X] GB 2096415 A 19821013 - ICI PLC
- [X] EP 0096482 A2 19831221 - ICI PLC [GB]
Designated contracting state (EPC)
AT DE ES FR SE
DOCDB simple family (publication)
GB 2190552 A 19871118; GB 2190552 B 19900418; GB 8708957 D0 19870520; AU 595873 B2 19900412; AU 7153087 A 19871119; CA 1266522 A 19900306; EP 0256613 A2 19880224; EP 0256613 A3 19900816; FI 872066 A0 19870511; FI 872066 A 19871116; MX 161736 A 19901220; NO 872005 D0 19870514; NO 872005 L 19871116; NZ 219934 A 19900327; ZM 3787 A1 19881028
DOCDB simple family (application)
GB 8708957 A 19870414; AU 7153087 A 19870414; CA 509201 A 19860515; EP 87303256 A 19870414; FI 872066 A 19870511; MX 642687 A 19870511; NO 872005 A 19870514; NZ 21993487 A 19870409; ZM 3787 A 19870505