Linear ultrasonic motor and optical apparatus including the same

A driving apparatus, comprising:

• a movable part comprising a vibrator including a piezoelectric element and a pressurization part being configured to bring the vibrator into pressure contact with a base part by applying impression force to the vibrator, the movable part being linearly driven;
• and
• a cover part being configured to receive reactive force of the impression force through intermediation of a rolling part, the cover part being fixed to the base part by a holding part extending in a direction crossing a movement direction of the movable part,
• wherein the rolling part is sandwiched by a guide part of the movable part extending in the movement direction of the movable part and a cover guide part of the cover part extending in the movement direction of the movable part, and
• wherein the guide part of the movable part is positioned on an outer side beyond a side of the holding part facing the movable part when the movable part is positioned at at least one movable end.

A lens device comprising a driving apparatus, said driving apparatus including:

• a movable part comprising a vibrator including a piezoelectric element and a pressurization part being configured to bring the vibrator into pressure contact with a base part by applying impression force to the vibrator, the movable part being linearly driven;
• and
• a cover part being configured to receive reactive force of the impression force through intermediation of a rolling part, the cover part being fixed to the base part by a holding part extending in a direction crossing a movement direction of the movable part,
• wherein the rolling part is sandwiched by a guide part of the movable part extending in the movement direction of the movable part and a cover guide part of the cover part extending in the movement direction of the movable part, and
• wherein the guide part of the movable part is positioned on an outer side beyond a side of the holding part facing the movable part when the movable part is positioned at at least one movable end.

A movable part of a driving apparatus, which is disposed between a base part and a cover part fixed to the base part and which is linearly driven with a rolling part interposed between the movable part and the cover part, the movable part comprising:

• a vibrator including a piezoelectric element;
• a pressurization part being configured to bring the vibrator into pressurized contact with the base part by applying impression force to the vibrator;
• and
• a guide part being configured to accommodate the rolling part,
• wherein the guide part comprises three guide parts, and the three guide parts are arranged so as to form a triangle by connecting each other the three guide parts by a straight line, and
• wherein the movable part is linearly driven so that an impression center of the pressurization part is positioned in the triangle formed by connecting each other the rolling parts accommodated in the three guide parts by the straight line.