Drive device and imaging apparatus

A drive device that drives an imaging optical system, the device comprising:

• a piezoelectric element;
• a drive shaft that receives vibration of the piezoelectric element and vibrates along an optical axis direction of the imaging optical system;
• an engagement member that is frictionally engaged with the drive shaft and is connected to the imaging optical system;
• and
• a processor that controls vibration of the piezoelectric element,
• wherein the imaging optical system is provided to receive vibration of the piezoelectric element and to be movable in a range including at least a first position and a second position,
• the processor performs control of moving the imaging optical system from the first position to the second position in a case in which a signal for instructing a power of the drive device to be turned off is received,
• the first position is a position within a movement range for imaging that guarantees optical accuracy of the imaging optical system,
• the second position is a position other than the movement range for imaging in a range in which the imaging optical system is engaged with the drive shaft via the engagement member, and
• in a case in which a maximum movement amount of movement of the imaging optical system within the movement range for imaging in the optical axis direction is denoted by A, an engagement length of engagement between the engagement member and the drive shaft is denoted by W, and a length of the drive shaft is denoted by L, a relationship of L>A+2W is satisfied.

A drive device that drives an imaging optical system, the device comprising:

• a piezoelectric element;
• a drive shaft that receives vibration of the piezoelectric element and vibrates along an optical axis direction of the imaging optical system;
• an engagement member that is frictionally engaged with the drive shaft and is connected to the imaging optical system;
• and
• a processor that controls vibration of the piezoelectric element,
• wherein the imaging optical system is provided to receive vibration of the piezoelectric element and to be movable in a range including at least a first position and a second position,
• the processor performs control of moving the imaging optical system from the first position to the second position in a case in which a signal for instructing a power of the drive device to be turned off is received,
• the first position is a position within a movement range for imaging that guarantees optical accuracy of the imaging optical system,
• the second position is a position other than the movement range for imaging in a range in which the imaging optical system is engaged with the drive shaft via the engagement member,
• a lubricant reservoir portion for retaining a lubricant is provided on a track of the drive shaft, and
• the second position is located closer to the movement range for imaging than the lubricant reservoir portion in the optical axis direction.

A drive device that drives an imaging optical system, the device comprising:

• a piezoelectric element;
• a drive shaft that receives vibration of the piezoelectric element and vibrates along an optical axis direction of the imaging optical system;
• an engagement member that is frictionally engaged with the drive shaft and is connected to the imaging optical system;
• and
• a processor that controls vibration of the piezoelectric element,
• wherein the imaging optical system is provided to receive vibration of the piezoelectric element and to be movable in a range including at least a first position and a second position,
• the processor performs control of moving the imaging optical system from the first position to the second position in a case in which a signal for instructing a power of the drive device to be turned off is received,
• the first position is a position within a movement range for imaging that guarantees optical accuracy of the imaging optical system,
• the second position is a position other than the movement range for imaging in a range in which the imaging optical system is engaged with the drive shaft via the engagement member,
• a lubricant reservoir portion for retaining a lubricant is provided on a track of the drive shaft, and
• the second position is located on a side opposite to the lubricant reservoir portion in the optical axis direction with the movement range for imaging interposed therebetween.