Rotary reciprocating drive actuator

A rotary reciprocating drive actuator, comprising:

• a base part;
• a movable magnet fixed to a shaft part to which a movable object is connected;
• and
• a drive unit including a core body and a plurality of coil bodies disposed around outside of parts of the core body, the drive unit being configured to generate a magnetic flux in the core body when a current is supplied, and drive the movable magnet in a rotary reciprocating manner by an electromagnetic interaction between the magnetic flux generated from the core body and the movable magnet,
• wherein the movable magnet is formed in a ring shape, and is configured by alternately magnetizing an even number of magnetic poles forming an S-pole and an N-pole at an outer periphery of the shaft part;
• a number of core magnetic poles as magnetic poles of the core body and a number of magnetic poles of the movable magnet are equal to each other;
• the core magnetic poles are disposed to face the movable magnet with an air gap therebetween on an outer peripheral side of the movable magnet in a direction orthogonal to the shaft part;
• the drive unit is provided with a magnet position holding part which is a magnetic material provided to face the movable magnet and magnetically attracts the movable magnet to a reference position of an operation;
• the core body has a shape that connects between one end portion side and another end portion side among an even number of the core magnetic poles so as to surround the even number of the core magnetic poles;
• the coil body is disposed at the core body adjacent to each of the even number of the core magnetic poles;
• each magnetic pole is disposed with a gap from a portion that surrounds the core magnetic poles in the core body;
• and
• a spacer part is disposed at the gap between each core magnetic pole and the portion.