초록 ▼

A liquid level indicator uses a conductive probe and when the circuit is energized a logic signal indicates whether the liquid is above or below a certain level. The signal is processed by a logic circuit and the output of the logic circuit controls an indicator circuit. An inhibit circuit provides

A liquid level indicator uses a conductive probe and when the circuit is energized a logic signal indicates whether the liquid is above or below a certain level. The signal is processed by a logic circuit and the output of the logic circuit controls an indicator circuit. An inhibit circuit provides an input to the logic circuit and prevents the indicator circuit from indicating low liquid within a start time delay period after energization of the sensing circuit. The logic circuit includes a time constant circuit which interposes time delays in the logic signal output of the logic circuit to prevent false indications from momentary changes in liquid level.

대표청구항 ▼

A liquid level indicator comprising: a sensing circuit responsive, when energized, to a liquid level for producing a first logic signal having one logic state when the liquid is above a predetermined level and another logic state when the liquid is below said predetermined level, an energizing circu

A liquid level indicator comprising: a sensing circuit responsive, when energized, to a liquid level for producing a first logic signal having one logic state when the liquid is above a predetermined level and another logic state when the liquid is below said predetermined level, an energizing circuit coupled with said sensing circuit and including a voltage source and a switch for energizing said sensing circuit, a logic circuit coupled with said sensing circuit and responsive to said first logic signal for producing a second logic signal in a first logic state in response to said first logic signal being in said one logic state and for producing said second logic signal in a second logic state in response to said first logic signal being in said another logic state, an indicator circuit coupled with said logic circuit and responsive to said second logic signal in said first logic state for signifying that said liquid is above said predetermined level and responsive to said second logic signal in said second logic state for signifying that said liquid is below said predetermined level, and inhibiting means responsive to energization of said sensing circuit and coupled with said logic circuit for holding said second logic signal in said first logic state for a predetermined time period after said sensing circuit is energized.