Resources Contact Us Home
Early warning heat sensor system

Image Number 2 for United States Patent #5384562.

A heat-sensitive alarm trigger is used to set off a fire alarm system having an alarm circuit with a rated trigger resistance. The alarm circuit is triggered when a resistance across two sensor leads, between which the alarm trigger is connected, falls below the rated trigger resistance. The heat-sensitive alarm trigger comprises a laminate structure which includes an optionally perforated first electrode layer and a second electrode layer. A barrier material layer which is disposed between the two electrode layers has a resistance above the rated trigger resistance. A layer of hydrated material is disposed on the perforated electrode layer. When the hydrated material is heated above a given alarm trigger temperature, moisture is given off through the holes in the first electrode and, as a result, the barrier layer becomes sufficiently conductive so as to lower a resistance across the electrodes to below the rated trigger resistance. In the alternative, the hydrated layer is the barrier layer sandwiched between the electrodes. When the barrier layer reaches a given trigger temperature, its resistance falls below the rated trigger resistance, and the alarm circuit is triggered.

  Recently Added Patents
Cryptographically generated addresses using backward key chain for secure route optimization in mobile internet protocol
Hydrogenolysis of ethyl acetate in alcohol separation processes
Communication apparatus, power supply control method, display apparatus, communication method, and computer program product
Information display device and program storing medium
Image processing apparatus, method, and storage medium for performing soft proof processing
Bend resistant cable
Blur correction device and imaging apparatus
  Randomly Featured Patents
Bed coil spring unit and method of making same
Low voltage signaling
Aggregation devices processing keep-alive messages of point-to-point sessions
Water soluble polyesters
Polyamide resin composition and molded article
Game dial settable to alter player's odds of success
Vacuum cleaner attachment for cleaning small crevices or the like, attachable to vacuum extension hoses of different sizes
Control of abnormal growth in dichloro silane (DCS) based CVD polycide WSix films
Centrally coordinated peer assignment
Optical fiber transmission system with noise loading