Apparatus for controlling motor drive and method for controlling thereof

An apparatus for controlling revolution drive of a motor comprising:

• a motor including a rotor and a plurality of coils for defining a plurality of excitation phases in accordance with rotational points of said rotor,
• means for supplying a plurality of drive currents in a successive order to said plurality of coils from a voltage source directly,
• means for detecting a rotational position of said rotor in each of said plurality of excitation phases,
• a CPU for detecting a number of revolution of said rotor and for generating a time setting signal for varying a current supply time in accordance with a difference between said number of revolution of said rotor and a predetermined target number of revolution of said rotor, and
• means for generating drive pulse signals of a determined pulse width in response to said timing signal from said CPU to said means for supplying a plurality of drive currents synchronized to said position signal from said means for detecting a rotor position, said drive pulse signals being a single pulse in each of said excitation phases.

An apparatus for controlling revolution drive of a motor comprising:

• a motor including a rotor and a plurality of coils for defining a number of excitation phases for making said rotor complete each one cycle revolution,
• means for supplying a plurality of drive currents to said plurality of coils in a successive order in said defined number of excitation phases,
• means for supplying a certain controlled value of constant drive current from a voltage source to said means for supplying a plurality of drive currents,
• means for detecting a rotational position of said rotor in each of said excitation phases,
• means for detecting a number of revolution of said rotor by using a rotor position signal from said means for detecting a rotational position of said rotor,
• means for switching between first and second motor drive control modes by detecting a small signal operation,
• means for setting a current supply time for an excitation of said coils in each of said excitation phases in accordance with a difference between said detected number of revolution of said rotor and a predetermined target number of revolution of said rotor during said first motor drive control mode during other operations than said small signal operation, and further for setting a current supply time to a full term of each of said excitation phases during said second control mode during said small signal operation, and
• means for setting a maximum value of said drive current during said first control mode and further for setting a certain value of said drive current in accordance with a detected difference between said detected number of revolution of said rotor and a predetermined target number of revolution of said rotor during said second control mode.

A method for controlling rotation drive of a motor including a rotor and a plurality of coils for defining a number of excitation phases, comprising the steps of:

• detecting a rotational position of said rotor in each of said excitation phases,
• detecting a number of revolution of said rotor by using a detected rotor position signal from said step of detecting a rotational position of said rotor,
• determining a current supply time during each of said excitation phases in accordance with a difference between said detected number of revolution from said step of detecting a number of revolution of said rotor and a predetermined target number of revolution, and
• supplying a plurality of drive current signals to said plurality of coils in a predetermined successive order synchronized to an excitation timing in response to said detected rotor position, said drive current signals having a single pulse in each of said excitation phases having a duration corresponding to said determined current supply time.

A method for controlling rotation drive of a motor including a rotor and a plurality of coils for defining a number of excitation phases, comprising the steps of:

• detecting a rotational position of said rotor in each of said excitation phases,
• detecting a member of revolution of said rotor by using a detected rotor position signal from said step of detecting a rotational position of said rotor,
• detecting a small signal operation,
• if said small signal operation is not detected, the method for providing drive currents includes the steps of:
• setting a maximum value of drive current,
• setting a PWM duty (B/A) in accordance with a detected difference between said detected number of revolution of said rotor and a predetermined target number of revolution,
• calculating one phase time (A) from said rotor position signal, and
• calculating said current supply time (B) from said PWM duty (B/A) and said one phase time (A), and further
• if said small signal operation is not detected, the method for providing drive currents includes the steps of:
• setting a certain value of drive current in accordance with a detected difference between said detected number of revolution of said rotor and a predetermined target member of revolution of said rotor,
• setting said PWM-duty to 100%, and
• setting a drive time to 100% in each excitation phase.

A method for controlling rotation drive of a motor including a rotor and a plurality of coils for defining a number of excitation phases, comprising the steps of:

• detecting a rotational position of said rotor in each of said excitation phases,
• detecting a number of revolution of said rotor by using a detected rotor position signal from said step of detecting a rotational position of said rotor,
• switching first and second motor drive control modes by detecting a small signal operation,
• setting a current supply time for an excitation of said coils in each of said excitation phases in accordance with a difference between said detected number of revolution of said rotor and a predetermined target number of revolution of said rotor during said first motor drive control mode during other operations than said small signal operation, and further for setting a current supply time to a full term of each of said excitation phases during said second control mode during said small signal operation, and
• setting a maximum value of said drive current during said first control mode and further setting a certain value of said drive current in accordance with a detected difference between said detected number of revolution of said rotor and a predetermined target number of revolution of said rotor during said second control mode.