Commissariat a L'energie Atomique

Compagnie Centrale Sicli

Daniel Barbier

Robert Poujois

Jean-Michel Ittel

Bernard Lauwick

Jean C Lancre

A physical quantity such as temperature, infrared radiation or smoke is detected by means of a conversion device for emitting an alarm signal whose amplitude is representative of the intensity of the physical quantity. The detector comprises a unit for measuring relative variations of the signal in time, for comparing them with a preset threshold level and for actuating the alarm when they exceed the threshold level.

Alarm detector responsive to rate change of a monitored condition

The detector comprises a transducer designed to convert to an electrical signal a physical quantity which is representative of an abnormal phenomenon. The output of the transducer is connected to one input of a comparator whose output is connected to a delay circuit. The output of the delay circuit controls a signal generator, the output of which is connected to the other input of the comparator, the signal delivered by the comparator being representative of the time-dependent variations of the signal delivered by the transducer.

Detector for abnormal phenomena

Alarm detector responsive to rate of change of a monitored condition

The connections between the two inputs of an amplifier and the two outputs of a signal source as well as between the outputs of the amplifier and the inputs of a downstream output element into which the amplifier delivers a signal are inverted periodically and simultaneously and integration is carried out between the outputs of the amplifier and the inputs of the output element. In addition, the inputs of the amplifier are short-circuited periodically, the frequencies of inversion and of short-circuiting being multiples of each other.

Growing community of inventors

Echirolles, France

Daniel Barbier