Combination door chime and particulate products of combustion detector
US3982237A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 1975 |
| Grant date | Sep 21, 1976 |
| Priority date | — |
| Expiry date | Feb 28, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B17/113
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A combination door chime and detector responsive to the particulate products of combustion passing through multiple passageways formed in the chime cover. The door chime includes conventional spaced tone bars each cooperating with a tuned resonator chamber. A tone bar striker mechanism capable of single-note, two-note, and sustained-repetitive note striking of the tone bars is disposed between the tone bars. A photoelectric particulate products of combustion detector is also disposed between the tone bars. The conventional low-voltage door and chime transformer serves as a power supply for both the combustion detector and the striker mechanism. The closing of a first remote door chime switch generates a single-note signal; the closing of a second remote door chime switch generates a two-note signal; and the detection of the particulate products of combustion generates a sustained-repetitive note which serves as an intense audible alarm. An optional voltage comparator and signal gate serves to generate a pulsing repetitive signal with a relative large time interval between successive pulses. This fourth signal indicates a malfunctioning of the particulate products of combustion dete…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.