A drive device for a vibration actuator, which makes it possible to perform low-speed and stable driving and expand a dynamic range of driving speed. A first switching circuit and a second switching circuit apply a first drive signal and a second drive signal for exciting vibration, to an electromechanical energy conversion element of a vibrating body. A position detection sensor acquires information on a relative position between the vibrating body and a driven body in pressure contact with each other. An MPU switches the first and second drive signal to a third drive signal and a fourth drive signal, respectively, based on the acquired information, to thereby change a position at which a largest one of peaks of amplitude of vibration excited in the vibrating body is formed.

A drive device for a vibration actuator, which makes it possible to perform low-speed and stable driving and expand a dynamic range of driving speed. A first switching circuit and a second switching circuit apply a first drive signal and a second drive signal for exciting vibration, to an electromechanical energy conversion element of a vibrating body. A position detection sensor acquires information on a relative position between the vibrating body and a driven body in pressure contact with each other. An MPU switches the first and second drive signal to a third drive signal and a fourth drive signal, respectively, based on the acquired information, to thereby change a position at which a largest one of peaks of amplitude of vibration excited in the vibrating body is formed.

A numerical control device is for machining a machining object by moving a tool and the machining object relative to each other along a movement path while applying vibration, by use of a drive axis provided for the tool or the machining object. The device includes a storage unit that holds an invalid frequency region, and a vibration condition determining unit to determine a frequency for the vibration, based on a rotational speed of a main shaft for rotating the machining object, a number of vibrations of the vibration in each one rotation of the main shaft, and the invalid frequency region.

A drive device for a vibration actuator, which makes it possible to perform low-speed and stable driving and expand a dynamic range of driving speed, includes first and second switching circuits, a position detection sensor, and a microprocessing unit (MPU). The first switching circuit and the second switching circuit apply a first drive signal and a second drive signal, for exciting vibration, to an electromechanical energy conversion element of a vibrating body. The position detection sensor acquires information on a relative position between the vibrating body and a driven body in press contact with each other. The MPU switches the first and second drive signals to third drive and fourth drive signals, respectively, based on the acquired information, to thereby change a position at which a highest one of peaks of amplitude of vibration excited in the vibrating body is formed.

A drive device for a vibration actuator, which makes it possible to perform low-speed and stable driving and expand a dynamic range of driving speed, includes first and second switching circuits, a position detection sensor, and a microprocessing unit (MPU). The first switching circuit and the second switching circuit apply a first drive signal and a second drive signal, for exciting vibration, to an electromechanical energy conversion element of a vibrating body. The position detection sensor acquires information on a relative position between the vibrating body and a driven body in press contact with each other. The MPU switches the first and second drive signals to third drive and fourth drive signals, respectively, based on the acquired information, to thereby change a position at which a highest one of peaks of amplitude of vibration excited in the vibrating body is formed.

A numerical control device is for machining a machining object by moving a tool and the machining object relative to each other along a movement path while applying vibration, by use of a drive axis provided for the tool or the machining object. The device includes a storage unit that holds an invalid frequency region, and a vibration condition determining unit to determine a frequency for the vibration, based on a rotational speed of a main shaft for rotating the machining object, a number of vibrations of the vibration in each one rotation of the main shaft, and the invalid frequency region.

A numerical control device is for machining a machining object by moving a tool and the machining object relative to each other along a movement path while applying vibration, by use of a drive axis provided for the tool or the machining object. The device includes a storage unit that holds an invalid frequency region, and a vibration condition determining unit to determine a frequency for the vibration, based on a rotational speed of a main shaft for rotating the machining object, a number of vibrations of the vibration in each one rotation of the main shaft, and the invalid frequency region.