Optical obscruation smoke monitor having a shunt flow path located between two access ports
February 28, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3500450 3544218 3708675 Photoelectric detector for smoke or the like Smoke detector with chamber for producing eddy currents Smoke detector and housing assembly therefore Smoke detector Smoke detector Device for the detection of foreign components in a gas and an application of the device Optical smoke detector InventorsAssigneeApplicationNo. 202565 filed on 02/28/1994US Classes:250/573, Fluent material in optical path340/630, Photoelectric356/438Exhaust, dust or smokeExaminersPrimary: Nelms, David C.Assistant: Le, Que T. Attorney, Agent or FirmInternational ClassG01N 015/06AbstractAn obscuration type optical smoke monitor is provided for use particularly in dusty and dirty environments. The smoke monitor comprises a housing enclosing a smoke monitoring chamber; two access ports located opposite each other on the housing; a shunt air flow path located between said two access ports; means to conduct air from said access ports through an optical chamber; a light emitting diode at the first end of said optical chamber, which light emitting diode produces a light beam axially through the center of said optical chamber; a photo transistor at the second end of said optical chamber to receive the light bean and issue an electrical signal proportional to the received light intensity; and an electronic module which provides variable electronic output, generating an analog output essentially proportional of the optical obscuration caused by the smoke. Baffle means are provided to minimize extraneous light scattering from dust and dirt in the air, | |
