Drive control apparatus for stepping motor

A driving control apparatus for a stepping motor having a full step driving mode where an exciting current for step driving is energized to each phase and a micro step driving mode where a step in the full step driving mode is divided into a plurality of steps and the exciting current, which is increased and decreased step by step, is energized to each phase, said driving control apparatus comprising:

• a drive control circuit, which causes a drive circuit to switch between a full step driving mode and a micro step driving mode at a timing such that an absolute value of an energized electrical current in each phase during the micro step driving mode is a same value and an energization value at the micro step driving mode is different from an energization value at the full step driving mode.

A driving apparatus for a stepping motor comprising:

• a memorizing circuit which memorizes a micro step driving table constituted by a combination of the energization values;
• a control circuit which sets a number of driving steps of the stepping motor;
• wherein said control circuit carries out micro step driving selectively by one of said micro step driving table and a calculation of a value of said micro step driving table with a first function depending upon an area in the number of driving steps.

A driving method for a stepping motor having a micro step driving mode where an exciting current, which is increased and decreased step by step, is energized to each phase, comprising:

• a drive control step which causes a drive circuit to perform energization to each phase by a predetermined combination of energization values to each phase, when said stepping motor rotates in one direction, and energization to each phase by a combination different from the predetermined combination of energization values to each phase when said stepping motor rotates in another direction.

A driving control method for a stepping motor having a full step driving mode where an exciting current for step driving is energized to each phase and a micro step driving mode where a step in the full step driving mode is divided into a plurality of steps and the exciting current, which is increased and decreased step by step, is energized to each phase, comprising:

• a drive control step which causes a drive circuit to switch between the full step driving mode and the micro step driving mode at a timing such that an absolute value of an energized electrical current in each phase during the micro step driving mode is the same value and energization value at the micro step driving mode is different from energization value at the full step driving mode.

A driving apparatus for a stepping motor using a micro step driving mode where an exciting current, which is increased and decreased step by step, is energized to each phase, comprising:

• a drive control circuit, which sets a number of driving steps of the stepping motor and which causes a drive circuit to perform energization to each phase by a predetermined combination of the energiztion values to each phase,
• wherein said control circuit causes said drive circuit to perform energization to each phase by a calculation of a value of said predetermined combination with a first function when the remaining number of driving steps of the stepping motor is equal to or less than a predetermined value.

A driving control apparatus for a stepping motor having a full step driving mode where an exciting current for step driving is energized to each phase and a micro step driving mode where a step in the full step driving mode is divided into a plurality of steps and the exciting current, which is increased and decreased step by step, is energized to each phase, said driving control apparatus comprising:

• a driving control circuit, which causes a drive circuit to switch between a full step driving mode and a micro step driving mode at a timing such that an absolute value of an energized electrical current in each phase during the micro step driving mode is a value close to the same value and an energization value at the micro step driving mode is different from an energization value at the full step driving mode.

A driving control method for a stepping motor having a full step driving mode where an exciting current for step driving is energized to each phase and a micro step driving mode where a step in the full step driving mode is divided into a plurality of steps and the exciting current, which is increased and decreased step by step, is energized to each phase, said driving apparatus comprising:

• a driving control step which causes a drive circuit to switch between the full step driving mode and the micro step driving mode at a timing such that an absolute value of an energized electrical current in each phase during the micro step driving mode is a value close to the same value and energization value at the micro step driving mode is different from an energization value at the full step driving mode.