Tape feeder and component mounter

A tape feeder comprising:

• a sprocket with teeth, the teeth engaging with feeding holes of component supply tape in which many components are arranged at a specified pitch;
• a gear concentrically fixed to a side surface of the sprocket;
• a motor that transmits rotation to the gear such that the component supply tape is fed intermittently by the specified pitch so that the components in the component supply tape can be picked up one by one by a suction nozzle of a component mounter;
• a magnetic member concentrically fixed to an inner circumference of the gear and configured to rotate together with the sprocket;
• a magnetic field detecting element arranged at a position facing a rotation region of the magnetic member on a side of the gear opposite to the sprocket and configured to output a signal in accordance with a magnetic field of the magnetic member;
• a rotation angle detecting circuit configured to process the output signal of the magnetic field detecting element to detect a rotation degree of the sprocket in terms of an absolute angle;
• and
• a control section including circuitry configured to control pitch feeding operation of the sprocket by the motor, the control section correcting the pitch feeding amount of the motor based on the rotation angle of the sprocket detected by the rotation angle detecting circuit for each pitch feeding operation of the sprocket immediately after the motor is started, and when the rotation angle of the sprocket detected by the rotation angle detecting circuit is deviated from a predetermined sprocket angle range the pitch feeding amount is corrected such that the rotation angle of each pitch feeding operation of sprocket is within the predetermined sprocket angle range.