Proximity switching device
AssigneeOmron Tateisi Electronics Co.
InventorsFumio Kamiya, Hisatoshi Nodera, Kenji Ueda, Hiroyuki Miyamoto
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Abstract
A proximity switching device is disclosed, which comprises an oscillating circuit including a detection coil, a signal producing circuit for producing a detection signal in response to an oscillating amplitude of said oscillating circuit, and an output circuit for producing an output signal in response to said detection signal. The output circuit comprises a pair of Darlington circuits and a driving transistor for driving said Darlington circuits, one of said Darlington circuits operating as a NPN transistor and another operating as a PNP transistor, said Darlington circuit being connected complementarily for providing complementary output signals.
Claims4
A proximity switching device, comprising:
- an oscillating circuit including a detection coil,
- a signal producing circuit for producing a detection signal in response to a change in the oscillation amplitude level of said oscillating circuit, and
- an output for producing an output signal in response to said detection,
- said output circuit comprising a pair of Darlington circuits and a driving transistor for driving said Darlington circuits,
- wherein one of said Darlington circuits operates as a NPN transistor and the other operates as a PNP transistor, said Darlington circuits being connected complementary to provide complementary output signals, and
- wherein one of said Darlington circuits is provided with a constant-current circuit which provides a constant base-biasing current to at least one of the transistors of the particular Darlington circuits.
Dependencies are inferred from the claim text.