Air chuck having first and second solenoid valves

An air chuck comprising:

• a chuck unit including a plurality of fingers;
• and
• a valve unit attached to a robot arm or a transport device, wherein
• the chuck unit includes a first pressure chamber and a second pressure chamber disposed on both sides of a piston configured to drive the plurality of fingers,
• the valve unit includes a first output air flow path connected to one of the first pressure chamber or the second pressure chamber, a second output air flow path connected to another one of the first pressure chamber or the second pressure chamber, a first solenoid valve connected to the first output air flow path, and a second solenoid valve connected to the second output air flow path,
• the first solenoid valve connects the first output air flow path to an air supply source when energized and opens the first output air flow path to atmosphere when de-energized, and
• the second solenoid valve opens the second output air flow path to the atmosphere when energized and connects the second output air flow path to the air supply source when de-energized, wherein
• the chuck unit is configured to be selectively connected to the valve unit at a first rotation position or a second rotation position, a rotation angle of the chuck unit around a central axis of the valve unit at the first rotation position being different from the rotation angle of the chuck unit around the central axis of the valve unit at the second rotation position,
• the first output air flow path is connected to the first pressure chamber and the second output air flow path is connected to the second pressure chamber at the first rotation position, and
• the first output air flow path is connected to the second pressure chamber and the second output air flow path is connected to the first pressure chamber at the second rotation position.