Encoder, driving apparatus, method for calculating absolute position, and method for manufacturing encoder

A driving apparatus comprising:

• a motor configured to move a moving body in a movable range;
• a position data obtainer configured to obtain superordinate data representing a position of the moving body in a superordinate section included in the movable range and subordinate data representing a position of the moving body in a subordinate section repeated in the superordinate section with higher resolution than that of the superordinate data;
• a storage in which a correction value capable of correcting a deviation amount generated in advance based on the deviation amount occurring in the superordinate data against the subordinate data and measured in advance, is recorded to be associated with an absolute position with lower resolution than that of the subordinate data of the moving body;
• a corrector configured to obtain, based on an absolute position with the low resolution when the superordinate data is obtained by the position data obtainer, a correction value associated with the absolute position from the storage and to correct the superordinate data based on the correction value;
• a section identifier configured to identify, based on the superordinate data corrected by the corrector and the subordinate data when the superordinate data is obtained, the subordinate section in which the subordinate data is obtained against the superordinate section;
• an absolute position calculator configured to calculate, based on at least the subordinate section identified by the section identifier and the subordinate data when the superordinate data is obtained, an absolute position with resolution nearly equal to that of the subordinate data of the moving body;
• and
• a control apparatus configured to control the motor based on the absolute position calculated by the absolute position calculator.

A method for calculating an absolute position comprising:

• obtaining superordinate data representing a position of a moving body in a superordinate section in which the moving body is capable of moving and subordinate data representing a position of the moving body in a subordinate section repeated in the superordinate section with higher resolution than that of the superordinate data;
• obtaining, from a storage in which a correction value capable of correcting a deviation amount generated in advance based on the deviation amount occurring in the superordinate data against the subordinate data and measured in advance, is recorded to be associated with an absolute position with lower resolution than that of the subordinate data of the moving body, and based on the absolute position with lower resolution than that of the subordinate data when the superordinate data is obtained, the correction value associated with the absolute position, and correcting the superordinate data based on the correction value;
• and
• identifying, based on the superordinate data corrected and the subordinate data when the superordinate data is obtained, the subordinate section in which the subordinate data is obtained against the superordinate section.

A method for manufacturing an encoder comprising:

• obtaining superordinate data representing a position of a moving body in a superordinate section in which the moving body is capable of moving and subordinate data representing a position of the moving body in a subordinate section repeated in the superordinate section with higher resolution than that of the superordinate data;
• identifying, based on the superordinate data and the subordinate data obtained, the subordinate section in which the subordinate data is obtained against the superordinate section;
• calculating, based on at least the subordinate section identified and the subordinate data obtained, an absolute position with resolution nearly equal to that of the subordinate data of the moving body;
• calculating a true absolute position of the moving body, based on subordinate data obtained;
• measuring, based on the absolute position calculated and the true absolute position calculated, a deviation amount occurring in the superordinate data against the subordinate data;
• generating, based on the deviation amount measured, a correction value capable of correcting the deviation amount;
• and
• associating the correction value generated with an absolute position with lower resolution than that of the subordinate data of the moving body and recording the correction value in a storage in an encoder.

An encoder comprising:

• a means for obtaining superordinate data representing a position of a moving body in a superordinate section in which the moving body is capable of moving and subordinate data representing a position of the moving body in a subordinate section repeated in the superordinate section with higher resolution than that of the superordinate data;
• a means for storing in which a correction value capable of correcting a deviation amount generated in advance, based on the deviation amount occurring in the superordinate data against the subordinate data and measured in advance, is recorded to be associated with an absolute position with lower resolution than that of the subordinate data of the moving body;
• a means for correcting the superordinate data based on a correction value, obtained from the means for storing based on an absolute position with the low resolution when the superordinate data is obtained by the means for obtaining, associated with the absolute position;
• and
• a means for identifying, based on the superordinate data corrected by the means for correcting and the subordinate data when the superordinate data is obtained, the subordinate section in which the subordinate data is obtained against the superordinate section.