Brushless motor

Claim 2

A brushless motor comprising: a field means having a permanent magnet type rotor for producing P field poles (P is an even number integer not less than 2); K-phase driving windings (K is an integer not less than 2) fixed to a stator; driving commanding means for generating a substantially sinusoidal driving command signal; and driving control means for supplying a substantially sinusoidal driving current to said driving windings responding to said driving command signal, said driving commanding means comprising: rotation detecting means for obtaining a pulse signal in synchronization with rotation of said rotor; time interval measurement means for measuring a timing interval of said pulse signal; and driving command generating means for estimating an estimated electric angle at an estimating interval shorter than said timing interval and responsive to a measurement result of said time interval measurement means, and generating the substantially sinusoidal driving command signal corresponding to said estimated electric angle.

Claim 3

A brushless motor in accordance with claim 1, wherein said driving command generating means comprises: electric angle estimating means for obtaining a generated timing signal at a time interval responding to the measurement result of said time interval measurement means, and estimating the estimated electric angle responding to generation of the generated timing signal; and command generating means for generating the substantially sinusoidal driving command signal corresponding to the estimated electric angle.

Claim 4

A brushless motor in accordance with claim 1, wherein said driving command generating means comprises: electric angle estimating means for obtaining a generated timing signal at a time interval responding to the measurement result of said time interval measurement means, and estimating the estimated electric angle responding to generation of the generated timing signal; and command generating means for generating the substantially sinusoidal driving command signal corresponding to the estimated electric angle; deviation amount detecting means for detecting a deviation of the estimated electric angle from a predetermined value at a timing of the pulse signal in said rotation detecting means; and deviation correcting means for, in accordance with the deviation, correcting the time interval of the generated timing signal.

Claim 5

A brushless motor in accordance with claim 1, wherein said driving command generating means comprises: electric angle estimating means for obtaining a generated timing signal at a time interval responding to the measurement result of said time interval measurement means, and estimating the estimated electric angle responding to generation of the generated timing signal; and command generating means for generating the substantially sinusoidal driving command signal corresponding to the estimated electric angle; and deviation correcting means for correcting the estimated electric angle to a predetermined value at a timing of the pulse signal in said rotation detecting means.

Claim 6

A brushless motor in accordance with claim 1, wherein said driving command generating means comprises: electric angle estimating means for obtaining a generated timing signal at a time interval responding to the measurement result of said time interval measurement means, and estimating the estimated electric angle responding to generation of the generated timing signal; and command generating means for generating the substantially sinusoidal driving command signal corresponding to the estimated electric angle; acceleration/deceleration detecting means for detecting an acceleration/deceleration state of said rotor; and acceleration/deceleration correcting means for, in accordance with an output of said acceleration/deceleration detecting means, correcting the time interval of the generated timing signal.

Claim 7

A brushless motor in accordance with claim 1, wherein said driving command generating means comprises: electric angle estimating means for obtaining a generated timing signal at a time interval responding to the measurement result of said time interval measurement means, and estimating the estimated electric angle responding to generation of the generated timing signal; and command generating means for generating the substantially sinusoidal driving command signal corresponding to the estimated electric angle; deviation amount detecting means for detecting a deviation of the estimated electric angle from a predetermined value at a timing of the pulse signal in said rotation detecting means; and deviation correcting means for, in accordance with the deviation, correcting the time interval of the generated timing signal; acceleration/deceleration detecting means for detecting an acceleration/deceleration state of said rotor; and acceleration/deceleration correcting means for, in accordance with an output of said acceleration/deceleration detecting means, correcting the time interval of the generated timing signal.

Claim 8

A brushless motor in accordance with claim 1, wherein said driving commanding means further comprises: position detecting means for generating a rotational position signal corresponding to a rotational position of said rotor; and start driving command generating means for, in a start process, generating the driving command signal in accordance with the rotational position signal.

Claim 9

A brushless motor in accordance with claim 1, wherein said driving commanding means uses said rotation detecting means for obtaining the pulse signal corresponding to a counter electromotive force generated in said driving windings during rotation.

Claim 10

A brushless motor comprising: a field means having a rotor for producing P field poles (P is an even number not less than 2); K-phase driving windings (K is an integer not less than 2) fixed to a stator; driving commanding means for generating a substantially sinusoidal driving command signal; and driving control means for obtaining a current feedback signal corresponding to a current supplied to said driving windings, and supplying a substantially sinusoidal driving current to said driving windings in accordance with a result of comparison between the driving command signal and the current feedback signal, said driving commanding means comprising: rotation detecting means for obtaining a pulse signal in synchronization with rotation of said rotor; time interval measurement means for measuring a timing interval of said pulse signal; electric angle estimating means for obtaining a generated timing signal at a time interval responding to the measurement result of said time interval measurement means, and estimating the estimated electric angle responding to generation of the generated timing signal; and command generating means for generating the substantially sinusoidal driving command signal corresponding to the estimated electric angle; deviation amount detecting means for detecting a deviation of the estimated electric angle from a predetermined value at a timing of the pulse signal in said rotation detecting means; and deviation correcting means for, in accordance with the deviation, correcting the time interval of the generated timing signal.

Claim 11

A brushless motor comprising: a field means having a rotor for producing P field poles (P is an even number not less than 2); K-phase driving windings (K is an integer not less than 2) fixed to a stator; driving commanding means for generating a substantially sinusoidal driving command signal; and driving control means for obtaining a current feedback signal corresponding to a current supplied to said driving windings, and supplying a substantially sinusoidal driving current to said driving windings in accordance with a result of comparison between the driving command signal and the current feedback signal, said driving commanding means comprising: rotation detecting means for obtaining a pulse signal in synchronization with rotation of said rotor; time interval measurement means for measuring a timing interval of said pulse signal; electric angle estimating means for obtaining a generated timing signal at a time interval responding to the measurement result of said time interval measurement means, and estimating the estimated electric angle responding to generation of the generated timing signal; and command generating means for generating the substantially sinusoidal driving command signal corresponding to the estimated electric angle; deviation amount detecting means for detecting a deviation of the estimated electric angle from a predetermined value at a timing of the pulse signal in said rotation detecting means; and deviation correcting means for, in accordance with the deviation, correcting the time interval of the generated timing signal.

Claim 12

A brushless motor in accordance with claim 9, wherein said driving commanding means further comprises: acceleration/deceleration correcting means for, in accordance with an output of said acceleration/deceleration detecting means, correcting the time interval of the generated timing signal.

Claim 13

A brushless motor in accordance with claim 9, wherein said driving commanding means further comprises: position detecting means for generating a rotational position signal corresponding to a rotational position of said rotor; and start driving command generating means for, in a start process, generating the driving command signal in accordance with the rotational position signal.

Claim 14

A brushless motor according to claim 9, wherein said driving commanding means uses said rotation detecting means for obtaining the pulse signal corresponding to a counter electromotive force generated in said driving windings during rotation.

Claim 15

A brushless motor comprising: a field means having a permanent magnet type rotor for producing P field poles (P is an even number not less than 2), K-phase driving windings (K is an integer not less than 2) fixed to a stator; current commanding means for generating a current command signal; current detecting means for obtaining a current feedback signal corresponding to a current supplied to said driving windings; transforming and comparing means for comparing the current feedback signal with the current command signal; and driving control means for supplying a substantially sinusoidal driving current to said driving windings in accordance with an output signal of said transforming and comparing means, said transforming and comparing means comprising: rotation detecting means for obtaining a pulse signal in synchronization with rotation of said rotor; time interval measurement means for measuring a timing interval of said pulse signal; electric angle estimating means for obtaining a generated timing signal at a time interval responding to a measurement result of said time interval measurement means, and estimating an estimated electric angle responding to generation of the generated timing signal; transform feedback means for obtaining a transformed feedback signal by operating coordinate transformation on the current feedback signal with the estimated electric angle; control signal generating means for obtaining a control signal responding to a result of comparison between the transformed feedback signal and the current command signal; transformed control signal generating means for obtaining a transformed control signal which is obtained by operating coordinate transformation on the control signal with the estimated electric angle; and output generating means for obtaining the output signal responding to the transformed control signal.

Claim 16

A brushless motor comprising: a field means having a permanent magnet type rotor for producing P field poles (P is an even number not less than 2), K-phase driving windings (K is an integer not less than 2) fixed to a stator; current commanding means for generating a current command signal; current detecting means for obtaining a current feedback signal corresponding to a current supplied to said driving windings; transforming and comparing means for comparing the current feedback signal with the current command signal; and driving control means for supplying a substantially sinusoidal driving current to said driving windings in accordance with an output signal of said transforming and comparing means, said transforming and comparing means comprising: rotation detecting means for obtaining a pulse signal in synchronization with rotation of said rotor; time interval measurement means for measuring a timing interval of said pulse signal; electric angle estimating means for obtaining a generated timing signal at a time interval responding to a measurement result of said time interval measurement means, and estimating an estimated electric angle responding to generation of the generated timing signal; transform feedback means for obtaining a transformed feedback signal by operating coordinate transformation on the current feedback signal with the estimated electric angle; control signal generating means for obtaining a control signal responding to a result of comparison between the transformed feedback signal and the current command signal; transformed control signal generating means for obtaining a transformed control signal which is obtained by operating coordinate transformation on the control signal with the estimated electric angle; and output generating means for obtaining the output signal responding to the transformed control signal.

Claim 17

A brushless motor in accordance with claim 13, wherein said transforming and comparing means further comprises: deviation amount detecting means for detecting a deviation of the estimated electric angle from a predetermined value at a timing of the pulse signal in said rotation detecting means; and deviation correcting means for, in accordance with the deviation, correcting the time interval of the generated timing signal.

Claim 18

A brushless motor in accordance with claim 13, wherein said transforming and comparing means further comprises: deviation correcting means for correcting the estimated electric angle to a predetermined value at a timing of the pulse signal in said rotation detecting means.

Claim 19

A brushless motor in accordance with claim 13, wherein said transforming and comparing means further comprises: acceleration/deceleration detecting means for detecting an acceleration/deceleration state of said rotor; and acceleration/deceleration correcting means for, in accordance with an output of said acceleration/deceleration detecting means, correcting the time interval of the generated timing signal.

Claim 20

A brushless motor in accordance with claim 13, wherein said transforming and comparing means further comprises: position detecting means for generating a rotational position signal corresponding to a rotational position of said rotor; and means for, in a start process, changing the output signal of said transforming and comparing means responding to the rotational position signal.

Claim 21

A brushless motor in accordance with claim 13, wherein said transforming and comparing means uses said rotation detecting means for obtaining the pulse signal corresponding to a counter electromotive force generated in said driving windings during rotation.