초록 ▼

A metal detection device is disclosed and includes a housing defining a central aperture. An induction member is mounted to the housing and surrounds the aperture for generating an output voltage in response to the presence of a metal object near the induction member. A mechanism is provided for cal

A metal detection device is disclosed and includes a housing defining a central aperture. An induction member is mounted to the housing and surrounds the aperture for generating an output voltage in response to the presence of a metal object near the induction member. A mechanism is provided for calibrating the induction member by comparing the output voltage to a reference voltage to establish a threshold voltage which is unaffected by transient fluctuations in the output voltage. A mechanism is also provided in the housing and spaced about the aperture for selectively sensing an object passing through the aperture. The sensing mechanism generates a detection signal in response to passage of an object through the aperture only upon activation of the sensing mechanism. A mechanism activates the sensing mechanism upon generation of an inductive member output voltage above the threshold voltage. Finally, a device is provided for triggering an alarm in response to the generation of the detection signal.

대표청구항 ▼

A metal detection device comprising: a housing defining a central aperture; an induction member mounted to said housing and surrounding said aperture for generating an output voltage in response to the presence of a metal object near said induction member; means for calibrating said induction member

A metal detection device comprising: a housing defining a central aperture; an induction member mounted to said housing and surrounding said aperture for generating an output voltage in response to the presence of a metal object near said induction member; means for calibrating said induction member by comparing said output voltage to a reference voltage to establish a threshold voltage which is unaffected by transient environmental fluctuations in said output voltage; means disposed in said housing and spaced about said aperture for selectively sensing an object passing through said aperture, said sensing means generating a detection signal in response to passage of an object through said aperture only upon activation of said sensing means; means for activating said sensing means upon generation of an inductive member output voltage above said threshold voltage; and means for triggering an alarm in response to the generation of said detection signal.