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US 7,733,040 B2Granted
Brushless motor
AssigneeSeiko Epson Corporation
InventorKesatoshi Takeuchi
Life of this patent
Estimating the term…
Abstract
In the m phase brushless motor, n (n<m) phase magnet coil groups are provided with magnetic sensors, while the remaining (m−n) phase magnet coil groups are not provided with magnetic sensors. The drive control circuit utilizes the sensor outputs of the n magnetic sensors to generates n sets of drive signals for the n phase magnet coil groups. The drive control circuit further generates (m−n) sets of drive signals for the (m−n) phase magnet coil groups not associated with the n magnetic sensors, using one or more of the sensor outputs of the n magnetic sensors in generation of each of the (m−n) sets of drive signals.
Claims12
A brushless motor comprising:
- a coil array having m phase magnet coil groups, where m is an integer equal to 3 or greater;
- a magnet array having a plurality of permanent magnets;
- n magnetic sensors associated with n phase magnet coil groups among the m phase magnet coil groups, where n is an integer equal to 2 or greater but less than m, wherein the n magnetic sensors are used for detecting relative position of the magnet array and the coil array;
- and
- a drive control circuit that utilizes the sensor outputs of the n magnetic sensors to drive the coil array;
- wherein the drive control circuit includes:
- a simulated sensor output generator that, based on computation using one or more of the sensor outputs of the n magnetic sensors as a variable, generates (m−n) simulated sensor outputs for the (m−n) phase magnet coil groups not associated with the n magnetic sensors;
- and
- a drive signal generator that generates m sets of drive signals for the m phase magnet coil groups, in response to m sensor outputs inclusive of the sensor outputs of the n magnetic sensors and the (m−n) simulated sensor outputs, and
- wherein the drive control circuit:
- generates n sets of drive signals for the n phase magnet coil groups associated with the n magnetic sensors using the respective sensor outputs of the n magnetic sensors;
- and
- generates (m−n) sets of drive signals for the (m−n) phase magnet coil groups not associated with the n magnetic sensors, using one or more of the sensor outputs of the n magnetic sensors in generation of each of the (m−n) sets of drive signals.
10 more elements
An electronic device, comprising:
- a brushless motor;
- and
- a driven member driven by the brushless motor,
- wherein the brushless motor includes:
- a coil array having m phase magnet coil groups, where m is an integer equal to 3 or greater;
- a magnet array having a plurality of permanent magnets;
- n magnetic sensors associated with n phase magnet coil groups among the m phase magnet coil groups, where n is an integer equal to 2 or greater but less than m, wherein the n magnetic sensors are used for detecting relative position of the magnet array and the coil array;
- and
- a drive control circuit that utilizes the sensor outputs of the n magnetic sensors to drive the coil array;
- wherein the drive control circuit includes:
- a simulated sensor output generator that, based on computation using one or more of the sensor outputs of the n magnetic sensors as a variable, generates (m−n) simulated sensor outputs for the (m−n) phase magnet coil groups not associated with the n magnetic sensors;
- and
- a drive signal generator that generates m sets of drive signals for the m chase magnet coil groups, in response to m sensor outputs inclusive of the sensor outputs of the n magnetic sensors and the (m−n) simulated sensor outputs, and
- wherein the drive control circuit:
- generates n sets of drive signals for the n phase magnet coil groups associated with the n magnetic sensors using the respective sensor outputs of the n magnetic sensors;
- and
- generates (m−n) sets of drive signals for the (m−n) phase magnet coil groups not associated with the n magnetic sensors, using one or more of the sensor outputs of the n magnetic sensors in generation of each of the (m−n) sets of drive signals.
14 more elements
A fuel cell equipped apparatus, comprising:
- a brushless motor;
- a driven member driven by the brushless motor;
- and
- a fuel cell for supplying power to the brushless motor,
- wherein the brushless motor includes:
- a coil array having m phase magnet coil groups, where m is an integer equal to 3 or greater;
- a magnet array having a plurality of permanent magnets;
- n magnetic sensors associated with n phase magnet coil groups among the m phase magnet coil groups, where n is an integer equal to 2 or greater but less than m, wherein the n magnetic sensors are used for detecting relative position of the magnet array and the coil array;
- and
- a drive control circuit that utilizes the sensor outputs of the n magnetic sensors to drive the coil array;
- wherein the drive control circuit includes:
- a simulated sensor output generator that, based on computation using one or more of the sensor outputs of the n magnetic sensors as a variable, generates (m−n) simulated sensor outputs for the (m−n) phase magnet coil groups not associated with the n magnetic sensors;
- and
- a drive signal generator that generates m sets of drive signals for the m phase magnet coil groups, in response to m sensor outputs inclusive of the sensor outputs of the n magnetic sensors and the (m−n) simulated sensor outputs, and
- wherein the drive control circuit:
- generates n sets of drive signals for the n phase magnet coil groups associated with the n magnetic sensors using the respective sensor outputs of the n magnetic sensors;
- and
- generates (m−n) sets of drive signals for the (m−n) phase magnet coil groups not associated with the n magnetic sensors, using one or more of the sensor outputs of the n magnetic sensors in generation of each of the (m−n) sets of drive signals.
15 more elements
Dependencies are inferred from the claim text.