Vibration actuator, and drive device, multi-axis stage unit, and articulated robot that use vibration actuator

A drive device comprising:

• one or more vibration actuators each of which comprising:
• vibrator devices that respectively have vibrators each of which includes an elastic member and an electro-mechanical energy conversion element;
• a contact member that contacts the vibrators and is movable in a predetermined direction relatively to the vibrators to drive a target;
• a restraint member that fixes a first vibrator device that is at least one of the vibrator devices to restrict a degree of freedom in the predetermined direction;
• and
• a flexible member that has predetermined rigidity in the predetermined direction, has rigidity, which is lower than the predetermined rigidity, in directions other than the predetermined direction, and connects a second vibrator device that is at least one of the vibrator devices to the first vibrator device;
• and
• a main body to which the one or more vibration actuators are fixed by the restraint member.

A multi-axis stage unit comprising:

• a stationary part;
• a stage that is movable with respect to the stationary part;
• and
• at least one vibration actuator that is provided in the stationary part and drives the stage, the vibration actuator comprising:
• vibrator devices that respectively have vibrators each of which includes an elastic member and an electro-mechanical energy conversion element;
• a contact member that contacts the vibrators and is movable in a predetermined direction relatively to the vibrators to drive the stage;
• a restraint member that fixes a first vibrator device that is at least one of the vibrator devices to restrict a degree of freedom in the predetermined direction;
• and
• a flexible member that has predetermined rigidity in the predetermined direction, has rigidity, which is lower than the predetermined rigidity, in directions other than the predetermined direction, and connects a second vibrator device that is at least one of the vibrator devices to the first vibrator device.

An articulated robot comprising:

• joints;
• movable parts that are connected by the joints;
• and
• vibration actuators that drive the movable parts, and each of the vibration actuators comprising:
• vibrator devices that respectively have vibrators each of which includes an elastic member and an electro-mechanical energy conversion element;
• a contact member that contacts the vibrators and is movable in a predetermined direction relatively to the vibrators to drive the movable parts;
• a restraint member that fixes a first vibrator device that is at least one of the vibrator devices to restrict a degree of freedom in the predetermined direction;
• and
• a flexible member that has predetermined rigidity in the predetermined direction, has rigidity, which is lower than the predetermined rigidity, in directions other than the predetermined direction, and connects a second vibrator device that is at least one of the vibrator devices to the first vibrator device.