Patent ID: 12231005

DESCRIPTION OF EMBODIMENTS

First Embodiment

A motor10according to the first embodiment of the present disclosure will be described with reference toFIGS.1-4. In addition, the arrows Z, R and C suitably shown in the drawings respectively indicate one side in a rotation axial direction, the outer side in a rotation radial direction and one side in a rotation circumferential direction of a rotor14that will be described later. Moreover, in the case of merely indicating the axial direction, the radial direction and the circumferential direction, unless specified otherwise, the arrows Z, R and C respectively indicate the rotation axial direction, the rotation radial direction and the rotation circumferential direction of the rotor14.

As shown inFIG.1, the motor10of the present embodiment is a motor designed to be used as an actuator in a vehicle. For example, the motor10of the present embodiment may be a motor for an electric clutch. Specifically, an electric clutch system of the vehicle is configured to include the motor, a speed reducer and a rotation-translation mechanism. The torque generated by the motor is multiplied by a speed reduction ratio in the speed reducer and converted into a linear-motion direction force in the rotation-translation mechanism. The electric clutch system is connected with a multiple disc clutch via a coned disc spring or a piston. The speed reducer may be implemented by planetary gears or mechanical paradox planetary gears. The rotation-translation mechanism may be implemented by a ball cam. The motor10is configured to include a stator12, the aforementioned rotor14that rotates upon generation of magnetism (or magnetic field) by the stator12, and sensors16(i.e., magnetic sensors) for detecting the rotation angle of the rotor14.

The rotor14is arranged radially inside the stator12that will be described later. The rotor14includes an annular rotor core18fixed on a rotating shaft that is not shown in the drawings, and a plurality of magnets20fixed to an outer peripheral part of the rotor core18. The magnets20are formed to have a rectangular shape when viewed from the radially outer side. Moreover, the magnets20are arranged at constant intervals in the circumferential direction.

As shown inFIGS.2and3, the stator12includes a stator core26that has a plurality of teeth22arranged at equal intervals in the circumferential direction and a back core24formed in an annular shape and connecting outer peripheral parts of the teeth22in the circumferential direction. Moreover, the stator12also includes a coil30that is formed by winding an electrically-conductive winding28around the teeth22of the stator core26. In addition, the stator12is supported by an annular housing31arranged on the outer peripheral side of the stator12.

To the stator core26, there is mounted an insulator32that is formed of an electrically-insulative material such as a resin material. The insulator32has a back-core covering portion34that covers both axial end faces of the back core24, and a tooth covering portion36that covers both axial end faces and both circumferential end faces of each of the teeth22.

As shown inFIGS.3and4, the sensors16of the present embodiment are so-called lead-type magnetic sensors. Each of the sensors16includes a sensor body38that is formed in the shape of a rectangular block. A central portion of the sensor body38constitutes a sensing point40for sensing the magnetism of the magnets20. Moreover, each of the sensors16also includes a plurality of (e.g., three in the present embodiment) legs42that protrude from the sensor body38toward one side thereof. Each of the sensors16is mounted to a circuit board44by soldering end portions of the legs42, on the opposite side thereof to the sensor body38, to the circuit board44. In the present embodiment, the circuit board44is formed in a substantially U-shape so as to extend both radially and circumferentially with its thickness direction coinciding with the axial direction. When viewed along the axial direction, the circuit board44covers part of the stator12in the circumferential direction. Moreover, in the present embodiment, the three sensors16are mounted to the circuit board44such that they are located at equal intervals in the circumferential direction. Furthermore, in the state of having been mounted to the circuit board44, the three sensors16protrude from the circuit board44to the other side in the axial direction. In addition, though the lead-type sensors16(i.e., magnetic sensors) are employed in the present embodiment, it is also possible to employ mount-type sensors46(i.e., magnetic sensors) as shown inFIG.5. It should be noted that portions of the sensors46corresponding to those of the sensors16as shown inFIG.4are designated by the same reference numerals as the corresponding portions of the sensors16.

As shown inFIGS.1and3, on the radially inner side of the sensor body38of each of the sensors16, there is provided a magnetism converging member48in close proximity to the sensor body38to converge the magnetism of the magnets20of the rotor14. The magnetism converging member48is formed of a magnetic material, such as iron, in a rectangular plate shape or a rectangular block shape. Moreover, the circumferential and axial dimensions W1and W2of the magnetism converging member48are set so that when viewed along the radial direction, the magnetism converging member48covers the sensing point40(seeFIG.4) of the sensor body38.

The sensor bodies38of the sensors16and the magnetism converging members48are held (or supported) by a busbar50that is mounted to the insulator32. As shown inFIG.3, the busbar50is formed of an electrically-insulative material such as a resin material. The busbar50has three sensor-holding portions52each of which is arranged between a circumferentially-adjacent pair of the teeth22. Moreover, each of the sensor-holding portions52is formed in a prismatic shape such that both axial end faces (i.e., bottom faces) thereof are shaped in an equilateral trapezoid tapering radially inward. In addition, the dimension from the end face (i.e., bottom face) on one axial side to the end face (i.e., bottom face) on the other axial side in each of the sensor-holding portions52is set such that the axial end faces (i.e., bottom faces) of each of the sensor-holding portions52do not protrude respectively from coil ends (i.e., axial ends of the coil30) to one axial side and the other axial side.

On the radially inner side in each of the sensor-holding portions52, there is formed a sensor insertion hole54that opens on the one side in the axial direction. Further, a portion56of the sensor insertion hole54on the one side in the axial direction is formed to expand toward the one side in the axial direction. Moreover, in the present embodiment, a corresponding one of the magnetism converging members48is held in a radially inner space on the closed end side (i.e., the other side in the axial direction) in the sensor insertion hole54. Further, the sensor body38of a corresponding one of the sensors16is held in a radially outer space on the closed end side (i.e., the other side in the axial direction) in the sensor insertion hole54.

The busbar50also has a fixing portion58that is formed in an annular shape and connects outer peripheral parts of the three sensor-holding portions52in the circumferential direction. The busbar50is mounted to the insulator32by fixing the fixing portion58to a surface of the back-core covering portion34of the insulator32on the one side in the axial direction.

Next, a process of inserting the magnetism converging members48and the sensor bodies38of the sensors16into the corresponding sensor insertion holes54will be described.

FIG.3shows the stator12and the like with the busbar50mounted to the insulator32. First, each of the three magnetism converging members48is inserted into the radially inner space on the closed end side in the sensor insertion hole54formed in a corresponding one of the three sensor-holding portions52of the busbar50. Consequently, as shown inFIG.6, each of the three magnetism converging members48is held in the radially inner space on the closed end side in the sensor insertion hole54formed in the corresponding one of the three sensor-holding portions52of the busbar50.

Next, as shown inFIG.3, by moving the circuit board44with the three sensors16mounted thereto to the other side in the axial direction, the sensor body38of each of the three sensors16is inserted into the radially outer space on the closed end side in the sensor insertion hole54formed in a corresponding one of the three sensor-holding portions52of the busbar50. Consequently, as shown inFIGS.6and7, the sensor body38of each of the three sensors16is held in the radially outer space on the closed end side in the sensor insertion hole54formed in the corresponding one of the three sensor-holding portions52of the busbar50.

Moreover, in the state where the sensor body38of each of the three sensors16is held in the radially outer space on the closed end side in the sensor insertion hole54formed in the corresponding one of the three sensor-holding portions52of the busbar50, an outer peripheral part of the circuit board44abuts a surface of the fixing portion58of the busbar50on the one side in the axial direction, as shown inFIG.2. In this state, the outer peripheral part of the circuit board44is fixed to the fixing portion58of the busbar50. In addition, in the case of employing the sensors46as shown inFIG.5instead of the sensors16, each of the sensors46may be inserted along with part of the circuit board44into the corresponding sensor insertion hole54.

FIG.8shows the stator12viewed from the side of a rotation center of the rotor14. In addition, in this figure, depiction of the rotor core18of the rotor14is omitted and the busbar50is shown by imaginary lines (i.e., dashed lines). As shown in this figure, in a state of being held on the closed end side in the sensor insertion hole54formed in one of the three sensor-holding portions52of the busbar50, each corresponding pair of one of the three magnetism converging members48and one of the sensor bodies38of the three sensors16is located in a circumferentially and axially intermediate area (more particularly, at substantially the center in the present embodiment) between a circumferentially-adjacent pair of the teeth22.

Next, operation and effects of the motor10according to the present embodiment will be described.

As shown inFIG.1, in the motor10according to the present embodiment, upon supply of electric current to the coil30of the stator12, a rotating magnetic field is generated around the stator12, causing the rotor14to rotate.

With rotation of the rotor14, the magnets20of the rotor14successively pass through the radially inner side of the sensor body38of each of the sensors16. Then, change in the magnetic flux density of the magnets20at the position of the sensor body38thereof is detected by each of the sensors16. Consequently, the rotation angle and/or the rotational speed of the rotor14can be calculated based on the detection results.

Moreover, in the present embodiment, each of the sensors16for detecting change in the magnetic flux density of the magnets20is arranged between a circumferentially-adjacent pair of the teeth22. With such a configuration, it becomes unnecessary to form recesses or the like in the teeth22to have the sensors16arranged therein. Consequently, it becomes possible to suppress deterioration of the characteristics of the motor10.

Further, in the present embodiment, each of the magnetism converging members48for converging the magnetism of the magnets20of the rotor14is provided in close proximity to the sensor body38of a corresponding one of the sensors16. Consequently, it becomes possible to suppress variation in the detection of change in the magnetism of the magnets20by the sensors16.

Hereinafter, analysis results of the effect of the magnetism converging members48will be described.

InFIGS.9A-9D, there are respectively shown a stator12A of a first analytical model, a stator12B of a second analytical model, a stator12C of a third analytical model and a stator12D of a fourth analytical model. It should be noted that in the stators12A,12B,12C and12D of these analytical models, members and portions corresponding to those in the above-described stator12(seeFIG.1) are designated by the same reference numerals as the corresponding members and portions in the stator12.

As shown inFIG.9A, the stator12A of the first analytical model include no magnetism converging members48as described above. Moreover, the analysis of the stator12A of the first analytical model was performed on the assumption that an air layer having a circumferential width of 1 mm and a radial thickness of 0.5 mm intervenes between an imaginary circle C1, which connects the radially inner ends of the teeth22in the circumferential direction, and the sensor body38of each of the sensors16. In addition, the diameter of the imaginary circle C1is 90.1 mm.

On the other hand, as shown inFIGS.9B-9D, the stators12B,12C and12D of the second, third and fourth analytical models include magnetism converging members48as described above. The circumferential center of the radially inner surface of each of the magnetism converging members48is located on the imaginary circle C1that connects the radially inner ends of the teeth22in the circumferential direction. Moreover, the analysis of the stator12B of the second analytical model was performed on the assumption that a magnetism converging member48having a circumferential width of 4 mm and a radial thickness of 0.5 mm intervenes between the imaginary circle C1, which connects the radially inner ends of the teeth22in the circumferential direction, and the sensor body38of each of the sensors16. The analysis of the stator12C of the third analytical model was performed on the assumption that a magnetism converging member48having a circumferential width of 4 mm and a radial thickness of 2 mm intervenes between the imaginary circle C1, which connects the radially inner ends of the teeth22in the circumferential direction, and the sensor body38of each of the sensors16. The analysis of the stator12D of the fourth analytical model was performed on the assumption that a magnetism converging member48having a circumferential width of 4 mm and a radial thickness of 4 mm intervenes between the imaginary circle C1, which connects the radially inner ends of the teeth22in the circumferential direction, and the sensor body38of each of the sensors16.

FIG.10Ashows a graph representing the change in magnetic flux density at the position of the imaginary circle C1(seeFIG.9A) in the stator12A of the first analytical model.FIG.10Bshows a graph representing the change in magnetic flux density at the circumferential position (shown respectively by (1), (2), and (3)) of the sensor body38(seeFIG.9A) of each of the sensors16in the stator12A of the first analytical model.

FIG.11Ashows a graph representing the change in magnetic flux density at the position of the imaginary circle C1(seeFIG.9B) in the stator12B of the second analytical model.FIG.11Bshows a graph representing the change in magnetic flux density at the position of the sensor body38(seeFIG.9B) of each of the sensors16in the stator12B of the second analytical model.

FIG.12Ashows a graph representing the change in magnetic flux density at the position of the imaginary circle C1(seeFIG.9C) in the stator12C of the third analytical model.FIG.12Bshows a graph representing the change in magnetic flux density at the position of the sensor body38(seeFIG.9C) of each of the sensors16in the stator12C of the third analytical model.

FIG.13Ashows a graph representing the change in magnetic flux density at the position of the imaginary circle C1(seeFIG.9D) in the stator12D of the fourth analytical model.FIG.13Bshows a graph representing the change in magnetic flux density at the position of the sensor body38(seeFIG.9D) of each of the sensors16in the stator12D of the fourth analytical model.

As shown inFIGS.10A,11A,12A, and13A, the magnetic flux density at the position of the imaginary circle C1(seeFIG.9B) is higher in the stators12B,12C and12D of the second, third and fourth analytical models including the magnetism converging members48than in the stator12A of the first analytical model including no magnetism converging members48. Moreover, as shown inFIGS.11A,12A, and13A, in the stators12B,12C and12D of the second, third and fourth analytical models including the magnetism converging members48, the magnetic flux density at the position of the imaginary circle C1(seeFIG.9B) increases with increase in the thickness of the magnetism converging members48.

Furthermore, as shown inFIGS.11B,12B and13B, comparing the change (or waveform) of magnetic flux density at the position of the sensor body38of each of the sensors16in the stator12B of the second analytical model with the change (or waveform) of magnetic flux density at the position of the sensor body38of each of the sensors16in the third and fourth stators12C and12D of the third and fourth analytical models, it can be seen that variation in the change (or waveform) of magnetic flux density at the position of the sensor body38of each of the sensors16is smaller in the case of the thickness of the magnetism converging members48being equal to 2 mm or 4 mm than in the case of the thickness of the magnetism converging members48being equal to 0.5 mm. Moreover, comparing the change (or waveform) of magnetic flux density at the position of the sensor body38of each of the sensors16in the stator12C of the third analytical model with the change (or waveform) of magnetic flux density at the position of the sensor body38of each of the sensors16in the stator12D of the fourth analytical model, it can be seen that there is almost no difference in variation in the change (or waveform) of magnetic flux density at the position of the sensor body38of each of the sensors16between the case of the thickness of the magnetism converging members48being equal to 2 mm and the case of the thickness of the magnetism converging members48being equal to 4 mm. From the above, it can be concluded that setting the ratio of the thickness to the width of the magnetism converging members48to be higher than or equal to 1/2, variation in the change (or waveform) of magnetic flux density at the position of the sensor body38of each of the sensors16can be suppressed.

In addition, it is preferable for the circumferential center of the radially inner surface of each of the magnetism converging members48to be located on the imaginary circle C1that connects the radially inner ends of the teeth22in the circumferential direction. However, it should be noted that the circumferential center of the radially inner surface of each of the magnetism converging members48may alternatively be located radially outside the imaginary circle C1.

In the present embodiment, with each corresponding pair of one of the sensor bodies38of the sensors16and one of the magnetism converging members48located in a circumferentially and axially intermediate area between a circumferentially-adjacent pair of the teeth22, it becomes possible to suppress increase in the axial size of the motor10. Moreover, it becomes unnecessary to mount a sensor magnet, which is dedicated for detection of the rotation angle of the rotor14, to the rotor14; consequently, the parts count of the motor10can be reduced.

Moreover, in the present embodiment, the magnetism converging members48and the sensor bodies38of the sensors16are held by the corresponding sensor-holding portions52of the busbar50. Consequently, it becomes possible to mount the busbar50to the insulator32after winding the winding28around the teeth22and then have the magnetism converging members48and the sensor bodies38of the sensors16held by the corresponding sensor-holding portions52of the busbar50. That is, the magnetism converging members48and the sensor bodies38of the sensors16can be held without impeding the process of winding the winding28around the teeth22.

In the present embodiment, the fixing portion58of the busbar50is fixed to the surface of the back-core covering portion34of the insulator32on the one side in the axial direction. Further, the circuit board44is fixed to the fixing portion58of the busbar50. Consequently, it becomes possible to perform the assembly of the stator12in the space on only one axial side of the stator core26.

In the present embodiment, the portions56of the sensor insertion holes54on the one side in the axial direction are formed to expand toward the one side in the axial direction. Consequently, even if the positions of the sensor bodies38of the sensors16mounted to the circuit board44are slightly deviated, the sensor bodies38of the sensors16can still be guided by the portions56of the corresponding sensor insertion holes54formed in the sensor-holding portions52of the busbar50to the closed end side in the corresponding sensor insertion holes54during insertion of the sensor bodies38of the sensors16into the corresponding sensor insertion holes54.

In addition, in the present embodiment, an example has been described above in which the sensor bodies38of the sensors16are held by the busbar50. However, the present disclosure is not limited to the above example. For example, as shown inFIG.14, the sensor bodies38of the sensors16may alternatively be held by the insulator32. In this case, the insulator32further has three connecting portions60each connecting, in the circumferential direction, those parts of the tooth covering portion36of the insulator32which respectively cover a circumferentially-adjacent pair of the teeth22on the one side in the axial direction. Moreover, in a circumferentially central part of each of the connecting portions60, there is formed a holding groove62that opens on both axial sides and the radially inner side. The sensor bodies38of the sensors16are fitted respectively into the holding grooves62formed in the connecting portions60of the insulator32from one axial side of the holding grooves62, thereby being held by insulator32. With this configuration, it becomes unnecessary to employ the above-described busbar50; consequently, it becomes possible to reduce the parts count of the motor10and simplify the assembly process of the motor10. Moreover, no magnetism converging members48as described above are employed in this configuration. Therefore, in terms of suppressing decrease in the accuracy of detecting the magnetism of the magnets20, it is preferable for the sensor bodies38of the sensors16to be located on the imaginary circle C1(seeFIG.9A) that connects the radially inner ends of the teeth22in the circumferential direction. However, it should be noted that the sensor bodies38of the sensors16may alternatively be located slightly radially outside the imaginary circle C1.

Second Embodiment

Next, a motor70according to the second embodiment of the present disclosure will be described. It should be noted that in the motor70according to the second embodiment, members and portions corresponding to those in the motor10according to the first embodiment are designated by the same reference numerals as the corresponding members and portions in the motor10and explanation thereof will be omitted hereinafter.

As shown inFIGS.15,16and17, in the motor70according to the present embodiment, the circuit board44is shaped such that the coil30wound around each of the teeth22of the stator core26is visible when the circuit board44is viewed along the axial direction. Consequently, the circuit board44does not overlap the coil ends of the coil30in the axial direction.

Specifically, as shown inFIGS.15,18and19, the circuit board44has a first extending portion72that extends along the radially inner ends of the teeth22of the stator core26and a plurality of second extending portions74that each extend radially outward from the first extending portion72and are arranged at equal intervals in the circumferential direction. The first extending portion72is formed in a substantially U-shape such that the radially outer and radially inner ends of the first extending portion72are arc-shaped and the radial width of the first extending portion72is constant along the circumferential direction. In the present embodiment, the circuit board44has six second extending portions74. The outer edges of the six second extending portions74are formed to be identical in shape to each other. More specifically, radially inner parts of the second extending portions74are formed in a substantially trapezoidal shape such that the circumferential dimension of the radially inner parts gradually increase in a radially outward direction. On the other hand, radially outer parts of the second extending portions74are formed in a substantially square shape such that the circumferential dimension of the radially outer parts is kept substantially constant in the radially outward direction.

Hereinafter, the six second extending portions74will be sequentially referred to as the second extending portion74A, the second extending portion74B, the second extending portion74C, the second extending portion74D, the second extending portion74E and the second extending portion74F from one side to the other side in the circumferential direction. In radially and circumferentially central parts of the second extending portions74A and74F, there are formed fixing holes74G into which fixing protrusions76formed in the insulator32are respectively inserted. In addition, the circuit board44is fixed to the insulator32by heat-staking the fixing protrusions76. On the other hand, in a circumferentially central part of the second extending portion74B, there are formed a plurality of terminal insertion holes74H at intervals in the radial direction to have a plurality of terminals (not shown in the drawings) respectively inserted therein. As shown inFIGS.19and20, to circumferentially central parts of radially inner end portions of the surfaces of the second extending portions74C,74D and74E on the other side in the axial direction, there are respectively mounted three mount-type sensors46. Moreover, as shown inFIG.15, in a state of the circuit board44having been fixed to the insulator32, each of the second extending portions74is located in a circumferentially intermediate area between a circumferentially-adjacent pair of the teeth22in an axial view from the one side. Further, as shown inFIG.21, in the state of the circuit board44having been fixed to the insulator32, each of the second extending portions74circumferentially overlaps the coil end of the coil30on the one side in the axial direction. Furthermore, as shown inFIGS.16and21, in the state of the circuit board44having been fixed to the insulator32, each of the sensors46mounted respectively to the second extending portions74C,74D and74E is located between a circumferentially central area between a circumferentially-adjacent pair of the teeth22in an axial view from the other side. In addition, in the state of the circuit board44having been fixed to the insulator32, each of the sensors46mounted respectively to the second extending portions74C,74D and74E is located in close proximity to ends of the magnets20of the rotor14on the one side in the axial direction.

As described above, in the motor70according to the present embodiment, the circuit board44is shaped such that the coil30wound around each of the teeth22of the stator core26is visible when the circuit board44is viewed along the axial direction. Consequently, it becomes possible to prevent heat dissipation of the coil30from being impeded by the circuit board44.

Moreover, in the motor70according to the present embodiment, in the state of the circuit board44having been fixed to the insulator32, each of the second extending portions74circumferentially overlaps the coil end of the coil30on the one side in the axial direction. Consequently, it becomes possible to prevent the circuit board44from protruding from the coil30to the one side in the axial direction, thereby suppressing increase in the axial dimension of the motor70.

Third Embodiment

Next, a motor78according to the third embodiment of the present disclosure will be described. It should be noted that in the motor78according to the third embodiment, members and portions corresponding to those in the above-described motors10and70are designated by the same reference numerals as the corresponding members and portions in the motors10and70and explanation thereof will be omitted hereinafter.

As shown inFIGS.22and23, compared to the motor70according to the second embodiment, the motor78according to the present embodiment further includes three magnetism converging members48and a support member80that supports the three magnetism converging members48.

The three magnetism converging members48are formed in a rectangular solid shape with its longitudinal direction coinciding with the axial direction. It should be noted that the three magnetism converging members48may alternatively be formed in a cylindrical shape or a columnar shape extending in the axial direction.

Similar to the insulator32, the support member80is formed of an electrically-insulative material such as a resin material. Specifically, the support member80has a plate-shaped outer peripheral portion80A extending along the surface of the back-core covering portion34of the insulator32on the other side in the axial direction and three block-shaped support portions80B extending from the outer peripheral portion80A radially inward and arranged at equal intervals in the circumferential direction. In the outer peripheral portion80A, there are formed fixing holes80C into which fixing protrusions84formed in the insulator32are respectively inserted. In addition, the support member80is fixed to the insulator32by heat-staking the fixing protrusions84. Each of the support portions80B is formed in a prismatic shape such that both axial end faces thereof are trapezoidal-shaped. The axial dimension of the support portions80B is set to be larger than the axial dimension of the outer peripheral portion80A. Moreover, the surfaces of the support portions80B on the other side in the axial direction is substantially flush with the surface of the outer peripheral portion80A on the other side in the axial direction. The three magnetism converging members48are respectively supported by radially inner end portions of the three support portions80B.

In a state of the support member80having been fixed to the insulator32so as to axially face the circuit board44, each of the three support portions80B is located in a circumferentially intermediate area between a circumferentially-adjacent pair of the teeth22in an axial view from the other side. Consequently, the three magnetism converging members48supported respectively by the three support portions80B of the support member80are axially located in close proximity respectively to the three sensors46mounted to the circuit board44and radially located in close proximity to the magnets20of the rotor14.

As described above, in the motor78according to the present embodiment, the magnetism of the magnets20of the rotor14can be guided to the three sensors46respectively via the three magnetism converging members48. Consequently, it becomes possible to suppress variation in the detection of change in the magnetism of the magnets20by the sensors46.

Moreover, with the configuration where the support member80supporting the three magnetism converging members48is fixed to the insulator32, it becomes possible to facilitate the positioning of the three magnetism converging members48with respect to the three sensors46.

Fourth Embodiment

Next, a motor86according to the fourth embodiment of the present disclosure will be described. It should be noted that in the motor86according to the fourth embodiment, members and portions corresponding to those in the above-described motors10,70and78are designated by the same reference numerals as the corresponding members and portions in the motors10,70and78and explanation thereof will be omitted hereinafter.

As shown inFIGS.24,25and26, in the motor86according to the present embodiment, the circuit board44is formed by cutting and removing part of a rectangular plate-shaped board-constituting member88. After the circuit board44is fixed to the insulator32, an end90A of the first extending portion72on the opposite side to the second extending portions74has the shape of a straight line perpendicular to the radial direction when viewed along the axial direction. Moreover, ends90B of the second extending portions74on the opposite side to the first extending portion72also have the shape of a straight line perpendicular to the radial direction when viewed along the axial direction. Furthermore, circumferential ends90C of the first extending portion72and the second extending portions74, which are circumferentially located outermost in the circuit board44, have the shape of a straight line parallel to the radial direction.

In addition, in spaces between circumferentially-adjacent teeth22different from those where the second extending portions74of the circuit board44are arranged, there are provided connection portions92to which power lines (not shown in the drawings) are connected.

As described above, in the motor86according to the present embodiment, the circuit board44is formed by cutting and removing part of the rectangular plate-shaped board-constituting member88. Consequently, compared to the motor70according to the second embodiment, the amount of removal of the board-constituting member88, which constitutes the circuit board44, can be reduced. That is, the yield rate of the board-constituting member88that constitutes the circuit board44can be improved. In addition, it is possible to improve the yield rate of the board-constituting member88that constitutes the circuit board44by forming at least one of the ends90A,90B and90C of the circuit board44in a straight-line shape.

Fifth Embodiment

Next, a motor94according to the fifth embodiment of the present disclosure will be described. It should be noted that in the motor94according to the fifth embodiment, members and portions corresponding to those in the above-described motors10,70,78and86are designated by the same reference numerals as the corresponding members and portions in the motors10,70,78and86and explanation thereof will be omitted hereinafter.

As shown inFIGS.27and28, in the motor94according to the present embodiment, the circuit board44is fixed, at a position offset to the one side in the axial direction with respect to that in the motor78according to the third embodiment, to the insulator32. Consequently, the three sensors46mounted to the circuit board44are located on the one side in the axial direction with respect to the coil end of the coil30. Moreover, in the motor94according to the present embodiment, the three magnetism converging members48are supported by the support member80at positions offset to the one side in the axial direction with respect to those in the motor78according to the third embodiment so as to correspond the positions of the three sensors46mounted to the circuit board44.

As described above, in the motor94according to the present embodiment, even with the configuration where the three sensors46mounted to the circuit board44are located on the one side in the axial direction with respect to the coil end of the coil30, it is still possible to guide the magnetism of the magnets20of the rotor14to the three sensors46via the three magnetism converging members48. Consequently, it is possible to suppress variation in the detection of change in the magnetism of the magnets20by the sensors16.

The above-described configurations of the motors according to the present disclosure can also be applied to motors where the magnets20of the rotor16are arranged radially outside the stator core26.

While the above particular embodiments of the present disclosure have been shown and described, it will be understood by those skilled in the art that the present disclosure is not limited to the above particular embodiments, but may be carried out through various modifications without departing from the spirit of the present disclosure.

Moreover, while the present disclosure has been described pursuant to the embodiments, it should be appreciated that the present disclosure is not limited to the embodiments and the structures. Instead, the present disclosure encompasses various modifications and changes within equivalent ranges. In addition, various combinations and modes are also included in the category and the scope of technical idea of the present disclosure.