Switching valve and suction-discharge device including the same

A switching valve comprising:

• a rotor
• that includes a pair of rollers rotatably mounted on both ends thereof;
• a rotor drive unit that rotationally drives the rotor;
• a pair of pressing members, each of the pair of pressing members being provided at a position where each of the pair of pressing members cooperates with each of the pair of rollers outside a revolution orbit of each of the pair of rollers revolving by rotation of the rotor;
• and
• a pair of tubes, each of the pair of tubes being disposed between the revolution orbit of each of the pair of rollers and each of the pair of pressing members,
• wherein a gap between each of the pair of pressing members and the revolution orbit of each of the pair of rollers is narrow, and a pair of pressing areas where the pair of rollers and the pair of pressing members cooperate with each other to press and block one or both of the pair of tubes is formed by revolution of the pair of rollers,
• the pair of rollers is rotationally movable among a position where the pair of tubes is both blocked, a position where only one of the pair of tubes is blocked, and a position where flows in the pair of tubes are both allowed,
• the pair of tubes is selectively blocked and opened from an outside by the pair of rollers and the pair of pressing members by the revolution of the pair of rollers,
• a rotation center axis of the rotor is disposed at a position deviating from a straight line connecting centers of rotation of the pair of rollers, and
• the pair of pressing members has the pair of pressing areas that is symmetrical with respect to a straight line passing through center of rotation of the rotor and extending a horizontal direction.