Patent Number: 7,134,332

Title: Liquid detecting apparatus, liquid-amount detecting apparatus, liquid detecting method, and liquid-amount detecting method

Abstract: A liquid-amount detecting apparatus detects the amount of a liquid in containers. The liquid-amount detecting apparatus includes a liquid detecting circuit and a determining unit. The liquid detecting circuit includes electrode units disposed so as to be in contact with the liquid in the containers, which becomes electrically conductive when in contact with the liquid, an impedance, and an AC-signal source. An AC signal not containing a DC component is input from the AC-signal source to the electrode units through the source impedance, and a signal representing the status of electric connection of the electrode units is output. Furthermore, based on the output signal, a binary signal representing the presence or absence of electrical connection of the electrode units is output. The determining unit determines the presence or absence of the liquid at the electrode units based on the binary signal output from the liquid detecting circuit.

Inventors: Eguchi; Takeo (Kanagawa, JP), Takenaka; Kazuyasu (Kanagawa, JP), Namekawa; Takumi (Kanagawa, JP)

Assignee: Sony Corporation

International Classification: G01F 23/00 (20060101)

Expiration Date: 2019-11-14 0:00:00