US 5,758,688 A · Automatic faucet

Abstract

In an automatic faucet having a hand sensor S to start and stop discharging water automatically, only hands can be detected accurately without detecting a washbowl (chinaware) and water stream erroneously. The sensor S comprises a light emitter and a light receiver. The directional axis d of a detection region (in which the light emitting region of the light emitter and the light receiving region of the light receiver are overlapped with each other) intersects the discharged water stream, and further the intersection angle between both is adjusted less than 70 degrees, irrespective of the flow rate of the discharged water. The reflected light levels detected by the light receiver are sampled periodically to calculate an average value and a variance value on the basis of at least eight most updated sampled data. Water discharge is started and stopped on the basis of the calculated average value and the variance value.

Claims13

Dependent claims

An automatic faucet for starting and stopping discharging water automatically by detecting presence or absence of hands with a non-contact reflection type active sensor, which comprises:

sampling data means for sampling data indicative of reflective signal levels on the active sensor periodically:
statistical calculating means for calculating at least one statistical value on the basis of a plurality of data from said sampling date means including updated data obtained by sampling;
and
means for determining the presence or absence of hands on the basis of the statistical value for starting and stopping water discharging.

1 more element

Dependencies are inferred from the claim text.

Automatic faucet

Life of this patent

Automatic faucet

Life of this patent

Abstract

Claims13