Method of fabricating a fire detector

A method of fabricating a fire detector utilizing:

• a smoke sensor unit which generates a smoke density signal indicative of a sensed smoke density as well as determines the fire-presence or not based upon the sensed smoke density to generate a fire-determination signal indicative of the determination, said smoke sensor unit having
• a power input terminal for receiving an operating voltage,
• a smoke density output terminal for providing said smoke density signal, and
• a fire-determination output terminal for providing said fire-determination signal;
• a thermal sensor unit which senses an environmental temperature to generate a temperature signal indicative thereof, said thermal sensor unit having
• a power input terminal for receiving the operating voltage, and
• a temperature output terminal for providing said temperature signal;
• a signal processing unit which determines the fire-presence or not based upon one of said smoke density signal and said temperature signal and generates a fire-determination signal indicative of the determination, said signal processing unit having:
• a smoke density input terminal for receiving said smoke density signal,
• a temperature input terminal for receiving said temperature signal,
• a power input terminal for receiving the operating voltage,
• a fire-determination output terminal for providing the fire-determination signal, and
• an interrogation signal input terminal for receiving an interrogation signal;
• a signal transmission unit adapted to be connected to a receiver and converting said fire-determination signal into a multiplex signal for multiplex transmission to said receiver, said signal transmission unit transforming the interrogation signal from said receiver into a suitable format to be processed at said signal processing unit, said signal transmission unit having:
• a power input terminal for receiving the operating voltage,
• an interrogation input terminal for receiving said interrogation signal,
• a fire-determination input terminal for receiving said fire-determination signal,
• an interrogation signal output terminal for transmitting said interrogation signal, and
• an multiplex signal output terminal for transmitting said multiplex signal;
• a power unit providing said operating voltage, said power unit including a switch circuit which is adapted to be connected to the receiver for providing a short-circuit signal in accordance with said fire-determination signal, said power unit further including a transfer circuit which transfers said interrogation signal from the receiver to said signal transmission unit as well as said multiplex signal from said signal transmission unit to the receiver, said power unit having:
• a power output terminal for providing said operating voltage,
• a multiplex signal input terminal for receiving said multiples signal,
• an interrogation output terminal for providing said interrogation signal,
• a fire-determination input terminal for receiving said fire-presence signal, and
• a port for connection with the receiver,
• said method comprising combining at least one of said smoke sensor unit and said thermal sensor unit with said power unit and optionally with at least one of said processing unit and said signal transmission unit.