Patent ID: 8301043

Claim:
A liquid-level detection device being configured to detect that a liquid level in a liquid storing container is in a predetermined position, comprising: a rotator disposed in the interior of the liquid storing container, the rotator being configured to be rotated by a liquid to be supplied to the liquid storing container, the rotator includes a rotary shaft and a blade member; the rotary shaft is rotatably attached to a wall of the liquid storing container, and the blade member is formed to extend radially from the rotary shaft and is configured to be hit by liquid to be supplied to the liquid storing container; a rotation detection mechanism detecting a rotation state of the rotator; and a liquid-level detection device detecting whether liquid level in the liquid storing container is positioned in a predetermined position based on a result detected by the rotation detection mechanism, wherein even when the liquid stored in the liquid storing container is not stirred, the liquid-level detection device detects whether the liquid level in the liquid storing container is positioned in a predetermined position.