http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-1439448-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_01d154741d5155e492a45ed03f58ee85 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/G08B17-113 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/H01J41-08 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/G01T7-125 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G01T7-12 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G08B17-11 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G08B17-113 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G08B17-10 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/H01J41-08 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G01N27-64 |
| filingDate | 1974-06-18-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1976-06-16-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-1439448-A |
| titleOfInvention | Ionization smoke detector |
| abstract | 1439448 Smoke detector HONEYWELL Inc 18 June 1974 [22 June 1973 (2) 2 July 1973] 26897/74 Heading G1N [Also in Division H1] An analogue signal from a dual ionization chamber assembly 11, 12 (see Division H1) is applied to the gate electrode G of a FET 123 connected across supply lines 120, 121 and having its source electrode 5 connected via junction 124 and a resistor 126 to a four terminal comparator switch 131 comprising a PNP and an NPN transistor connected for positive feedback. A reference terminal 132 of the switch 131 is connected to the adjustable wiper of a potentiometer 136 which permits selection of a desired reference voltage at terminal 132. Further terminals 133 and 134 of the switch 131 are connected respectively to a delay circuit 140, 141 and a transistor 142 the collector load circuit of which includes a resistor 143 and a light emitting diode LED. Terminals 1 to 7 of the detector circuit 10 are connected to a common panel 111 containing a D.C. source, a test switch, resetting switch 156, alarm relay 153, voltmeters 154 and 155 for indicating the voltages at junction 124 and terminal 132, and an optional relay 152 for indicating changes in current consumption of the whole circuit. With no smoke in the sensing chamber 12, the circuit is adjusted so that the switch 131 does not operate. The delay circuit 140, 141 ensures that the switch is not operated by transient volt- ages. With smoke present in the chamber 12, the switch 131 operates to light the LED and to energize the alarm relay 153. In an alternative circuit Fig. 9, (not shown), the switch 131 is replaced by a silicon controlled switch. |
| priorityDate | 1973-06-22-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
| Predicate | Subject |
|---|---|
| isDiscussedBy | http://rdf.ncbi.nlm.nih.gov/pubchem/compound/CID5461123 http://rdf.ncbi.nlm.nih.gov/pubchem/substance/SID419559541 |
Total number of triples: 19.