JP6659169B2 - Rotor and rotating electric machine - Google Patents

Description

  The present invention relates to a rotor and a rotating electric machine of a rotating electric machine having a structure for fixing a sensor magnet, in particular, a sensor magnet is hardly broken, a position sensor can be easily installed, and the rotor position detection accuracy is excellent. .

  2. Description of the Related Art In a conventional rotary electric machine, a rotary electric machine that mounts an embedded magnet rotor having a magnet embedded therein and realizes high efficiency and high torque has attracted attention. In the following description, an embedded magnet rotor (hereinafter, referred to as “IPM rotor” using an abbreviation of “Interior Permanent Magnet” written in English) includes a rotating magnet (hereinafter, referred to as “main magnet”) and a rotor. (Hereinafter, referred to as “sensor magnet”). There is a type in which the magnetic flux of the sensor magnet is detected by a position sensor such as a Hall element to detect the phase of the rotor.

  On the other hand, there is a rotor in which a magnet is assembled on the outer peripheral surface of the rotor (hereinafter, referred to as "SPM rotor" using an abbreviation of "Surface Permanent Magnet" in English). In the SPM rotor, the magnetic flux of the main magnet is often directly detected by a sensor.

  In recent years, in order to quickly respond to customer requirements, a rotating electric machine has been developed that shares parts of a stator and can support both an IPM rotor and an SPM rotor. The main magnet and the sensor magnet are generally weak in tensile force and easily broken. Therefore, when integrally forming the magnet, it is necessary to suppress the force applied to the magnet. In particular, when the magnet receives an internal pressure, the larger the diameter, the greater the tensile force and the easier it is to break.

  For example, Patent Literature 1 proposes a method of embedding a main magnet in a hole provided in a rotor core and integrally molding the main magnet with a resin to fix the main magnet. After the rotation detecting sensor magnet is fixed to the sensor magnet support member, it is integrally molded with the permanent magnet and fixed. Therefore, the method is easy to manufacture and assemble without using screws and the like.

  Further, Patent Document 1 has a structure in which the outer periphery of the sensor magnet is covered with a resin. In this structure, since the molding pressure is applied from the outer peripheral side during molding, the received force becomes a compressive force, and the sensor magnet is not easily broken. The main magnet is embedded in the hole of the rotor core, and is hardly cracked because the molding pressure receives only the compressive force in the axial direction.

  Another patent document 2 proposes a structure in which a ring-shaped main magnet and a sensor magnet are integrally molded with a resin together with a shaft. In this patent document 2, the end face of the main magnet is made uneven so that a resin flow path is secured, and the resin is filled on the outer periphery before the resin is filled on the inner periphery of the sensor magnet. Is preventing.

Japanese Patent No. 4666934 JP 2014-187754 A

  In the conventional patent document 1, since the sensor magnet is disposed on the inner peripheral side of the main magnet, the position detecting sensor must be disposed on the inner peripheral side of the rotor, which complicates the sensor support structure and reduces the number of parts. To increase. Further, in order to improve the detection accuracy of the sensor, it is necessary to shorten the distance between the sensor and the sensor magnet. However, since it is necessary to adjust in the radial direction, dimensional control is difficult.

  Further, when the sensor element is mounted on a substrate and connected to a circuit for stabilizing a sensor signal, it is necessary to bring the flat substrate into close proximity to the inner periphery of the sensor magnet, which is a cylindrical surface. Further, when the SPM rotor and the IPM rotor are diverted by a common stator, there is a problem that there is a restriction that the inner diameter of the magnet of the SPM rotor and the inner diameter of the sensor magnet of the IPM rotor are aligned.

  In another conventional patent document 2, sensors are arranged in the axial direction. However, there is a problem that there is a limitation in material selection only when a material that can be manufactured in a complicated shape such as a resin magnet is used for the main magnet. There was a point.

  The present invention has been made in order to solve the above-described problems, and provides a rotor and a rotating electric machine in which a sensor magnet is not easily broken, a position sensor can be easily installed, and the rotor position detection accuracy is excellent. The purpose is to do.

The rotor of the present invention
A cylindrical rotor core,
An annular sensor magnet disposed coaxially with the rotor core on one axial end of the rotor core,
A resin portion that covers the sensor magnet and is fixed to the rotor core,
The rotor core has a plurality of pin insertion holes at different positions in the circumferential direction on one end side in the axial direction,
A plurality of pins that are inserted into the pin insertion holes of the rotor core on the other end side in the axial direction,
A plurality of notches are provided at different positions in the circumferential direction on the other end side in the axial direction.
Further, the rotating electric machine of the present invention includes the above-mentioned rotor,
A stator arranged coaxially with the rotor.

According to the rotor and the rotating electric machine of the present invention,
The sensor magnet is not easily broken, the position sensor can be easily installed, and the accuracy of detecting the position of the rotor is excellent.

FIG. 1 is a plan view showing a configuration of a rotor according to Embodiment 1 of the present invention. FIG. 2 is a side view schematically illustrating an internal structure of the rotor illustrated in FIG. 1. FIG. 2 is a top view illustrating a configuration of an outer race of the rotor core illustrated in FIG. 1. FIG. 2 is a top view illustrating a configuration of an inner race of the rotor core illustrated in FIG. 1. FIG. 4 is a perspective view illustrating a configuration of a main magnet accommodated in an outer race of the rotor core illustrated in FIG. 3. FIG. 2 is a top view illustrating a configuration of a sensor magnet of the rotor illustrated in FIG. 1. FIG. 7 is a side view illustrating a configuration of the sensor magnet illustrated in FIG. 6. FIG. 7 is a perspective view illustrating a configuration of a sensor magnet illustrated in FIG. 6. FIG. 4 is a cross-sectional view illustrating a relationship between a rotor core and a pin in a cross section taken along line AA of the outer race of the rotor core illustrated in FIG. 3. FIG. 4 is a cross-sectional view illustrating a relationship between the rotor core and a tapered portion in a cross section taken along line BB of the outer race of the rotor core illustrated in FIG. 3. FIG. 14 is a diagram for explaining a magnetic flux distribution of a sensor magnet passing in the Q direction of the rotor shown in FIG. 13 and a configuration of the sensor magnet. FIG. 3 is a cross-sectional view illustrating a flow of resin around a sensor magnet illustrated in FIG. 2. FIG. 2 is an explanatory view schematically illustrating a mounting structure of the rotor illustrated in FIG. 1. FIG. 2 is a cross-sectional view illustrating a configuration of a rotating electric machine using the rotor illustrated in FIG. 1. FIG. 15 is a perspective view illustrating an appearance of the rotating electric machine illustrated in FIG. 14.

Embodiment 1 FIG.
Hereinafter, embodiments of the present invention will be described. The rotor 1 according to the first embodiment will be described as an IPM rotor. FIG. 1 is a plan view showing a configuration of a rotor according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional side view for schematically explaining the internal structure of the rotor shown in FIG. FIG. 3 is a top view showing the configuration of the outer race of the rotor core shown in FIG. FIG. 4 is a top view showing the configuration of the inner race of the rotor core shown in FIG.

  FIG. 5 is a perspective view showing a configuration of a main magnet housed in the outer race of the rotor core shown in FIG. FIG. 6 is a top view showing the configuration of the sensor magnet of the rotor shown in FIG. FIG. 7 is a side view showing the configuration of the sensor magnet shown in FIG. FIG. 8 is a perspective view showing the configuration of the sensor magnet shown in FIG. FIG. 9 is a diagram for explaining the magnetic flux distribution of the sensor magnet passing in the Q direction of the rotor shown in FIG. 13 and the configuration of the sensor magnet.

  FIG. 10 is a cross-sectional view for explaining the flow of resin around the sensor magnet shown in FIG. FIG. 11 is a cross-sectional view for explaining the relationship between the rotor core and the pin in a cross section taken along line AA of the outer race of the rotor core shown in FIG. FIG. 12 is a cross-sectional view illustrating the relationship between the rotor core and the tapered portion in a cross section taken along line BB of the outer race of the rotor core shown in FIG. FIG. 13 is an explanatory view schematically showing the rotor mounting structure shown in FIG. FIG. 14 is a sectional view showing a configuration of a rotating electric machine using the rotor shown in FIG. FIG. 15 is a perspective view showing the appearance of the rotating electric machine shown in FIG.

  1 and 2, the rotor 1 includes a rotor core 12, a sensor magnet 2, and a resin part 11. The rotor core 12 includes an outer ring 5, an inner ring 7, and a main magnet 9 described later. The sensor magnet 2 is formed in an annular shape disposed coaxially with the rotor core 12 at one end Y1 of the rotor core 12 in the axial direction Y. The sensor magnet 2 is arranged outside the main magnet 9 installed on the rotor core 12 in the radial direction X. The sensor magnet 2 detects a rotational position of the rotor core 12. The rotor core 12 and the sensor magnet 2 are integrally fixed by the resin portion 11.

  3 and 4, the outer ring 5 and the inner ring 7 are formed in an annular shape. As the material, for example, an electromagnetic steel sheet is used. The outer race 5 and the inner race 7 made of thin plates are laminated to a predetermined thickness in the axial direction Y to form the rotor core 12.

  As illustrated in FIG. 3, the outer ring 5 includes an insertion hole 61, a pin insertion hole 62, an uneven portion 51, a convex portion 52, and a space portion 53. The insertion hole 61 is a hole for inserting a main magnet 9 described later. A plurality of insertion holes 61 are provided at different locations in the circumferential direction Z, here, an example in which the number of poles is 10, is formed at 10 locations at equal intervals in the circumferential direction Z. In addition, although the example in which the number of poles is 10 is shown, the number is not limited to this, and other poles can be similarly formed.

  The pin insertion holes 62 are holes formed continuously at both ends of each of the insertion holes 61. The pin insertion hole 62 is a hole for inserting a pin 21 of the sensor magnet 2 described later. The example in which the pin insertion hole 62 is formed so as to communicate with the insertion hole 61 has been described. However, the present invention is not limited to this, and the pin insertion hole 62 may be formed as a separate hole from the insertion hole 61 as appropriate.

  The space 53 is a circular space formed at a center position of the outer ring 5 for disposing an inner ring 7 described later. A plurality of uneven portions 51 are formed at different locations in the circumferential direction Z and at different locations in the radial direction X. The uneven portion 51 is used for caulking and fixing when the thin outer ring 5 is laminated. A plurality of protrusions 52 are formed at different locations in the circumferential direction Z of the inner periphery of the outer ring 5 in the radial direction X and project inward in the radial direction X.

As shown in FIG. 4, the inner ring 7 includes a shaft insertion hole 63, an uneven portion 71, and a concave portion 72.
The shaft insertion hole 63 is a hole formed at the center position of the inner ring 7. The shaft insertion hole 63 is a hole for inserting a shaft 8 described later. The plurality of uneven portions 71 are formed at different locations in the circumferential direction Z. The uneven portion 71 is used for caulking and fixing when the thin inner ring 7 is laminated. A plurality of recesses 72 are formed in the outer periphery of the inner ring 7 in the radial direction X at positions corresponding to the protrusions 52 of the outer ring 5 and are recessed inward in the radial direction X.

  Therefore, when the inner ring 7 is installed in the space 53 of the outer ring 5, the projection 52 of the outer ring 5 and the recess 72 of the inner ring 7 engage with each other. Then, the displacement of the outer race 5 and the inner race 7 is prevented by the action of the rotating torque. Then, the rotor core 12 is formed by inserting the main magnet 9 shown in FIG. 5 into each of the ten insertion holes 61 of the outer ring 5. As described above, by configuring the rotor core 12 with the individual components of the outer ring 5 and the inner ring 7, the electrolytic corrosion of the rotor 1 is suppressed. Further, as shown in FIG. 5, the main magnet 9 can be formed in a simple shape, and there is no restriction on material selection.

  As shown in FIGS. 6, 7, and 8, the sensor magnet 2 includes a pin 21, a notch 22, and a taper 23. The pins 21 are formed at two different positions in the circumferential direction Z, here, two places separated by 180 degrees, so as to protrude toward the other end Y2 in the axial direction Y. The pin 21 is formed in a cylindrical shape. The pin 21 may have a shape other than a column shape, and for example, may be formed in a shape such as a cone or a triangular prism. Further, the number of pins 21 may be two or more, and is not limited.

  The notch 22 is formed on the other end Y2 in the same direction as the direction in which the pin 21 is formed in the axial direction Y. The notch 22 is formed at a different position in the circumferential direction Z so as to be recessed at one end Y1 in the axial direction Y. The notch portions 22 are formed at equal intervals in the circumferential direction Z at the same number of poles as 10 places. The notch portion 22 is formed for the purpose of improving the fluidity of the resin portion 11 when fixing the rotor core 12 and the sensor magnet 2.

  The tapered portion 23 is formed on the inner peripheral side of the sensor magnet 2 on the other end Y2 in the same direction as the direction in which the pins 21 are formed in the axial direction Y. The tapered portion 23 has a shape in which the width in the radial direction X decreases from one end Y1 in the axial direction Y to the other end Y2 on which the pin 21 is formed (in particular, see FIGS. 10 and 12). The sensor magnet 2 is disposed such that the other end Y2 in the axial direction Y on which the pins 21 are formed faces the upper surface of the rotor core 12. Then, the pin 21 is inserted into a pin insertion hole 62 formed in the outer ring 5.

  As described above, the sensor magnet 2 has a complicated shape such as the cutout portion 22 and the tapered portion 23. For this reason, in order to manufacture efficiently, a plastic magnet that can be molded with a mold by mixing a resin and a magnetic material as a material is used. Therefore, since the sensor magnet 2 is formed by a mold, a gate cutting portion 15 described later is inevitably formed at a gate (filling opening) for filling the plastic magnet into the mold.

  Here, details of the formation position of the cutout portion 22 of the sensor magnet 2 and the formation position of the gate cutting portion 15 of the sensor magnet 2 will be described with reference to FIG. FIG. 9 is a diagram showing a magnetic flux distribution of the sensor magnet 2 passing in the Q direction of the rotor 1 shown in FIG. 13 and a developed view showing the sensor magnet 2 at a location corresponding to the magnetic flux distribution. In the diagram showing the magnetic flux distribution, the horizontal axis indicates the position in the rotation direction of the rotor 1, any position is set to 0 degree, and is expanded up to 360 degrees in the circumferential direction. The vertical axis indicates the amount of magnetic flux at each position.

  A position sensor 44 for detecting the position of the rotor 1, which will be described later, detects a point 17 (hereinafter, referred to as a zero cross point 17) at which the magnetic flux of the sensor magnet 2 switches between the N pole and the S pole as shown in FIG. Therefore, the notch 22 needs to be formed at a position that does not overlap with the position of the zero cross point 17 in the circumferential direction Z. Therefore, the notch 22 is formed in the circumferential direction Z at an intermediate position between a plurality of zero cross points 17 of the magnetic flux waveform of the sensor magnet 2.

  This is because the thickness of the sensor magnet 2 near the position of the zero cross point 17 is formed to be thick, and a sufficient amount of magnetic flux near the position of the zero cross point 17 is secured. By securing the amount of magnetic flux in this way, the position detection accuracy of the position sensor 44 increases. Therefore, the notch 22 where the thickness of the sensor magnet 2 becomes thinner needs to be formed at a position that does not overlap with the position of the zero cross point 17.

  Next, when the sensor magnet 2 is molded with a plastic magnet, a weld line (welding line) 16 is formed between the gates as shown in FIG. 9 due to the merging of the flows of the plastic magnets. The weld line 16 is formed between the gates, that is, between the gate cut portions 15 in the circumferential direction Z.

  From the necessity of securing the strength of the sensor magnet 2, it is necessary to set the weld line 16 so that the weld line 16 does not overlap the notch 22. Further, deterioration of the magnetic characteristics of the sensor magnet 2 due to the weld line 16 may affect the position detection accuracy of the position sensor 44. Therefore, it is necessary to set so that the weld line 16 does not overlap the zero cross point 17.

  Therefore, it is necessary to set a position where the weld line 16 of the sensor magnet 2 may be formed at a position where the notch portion 22 and the zero cross point 17 do not overlap. Specifically, the gate cutting portions 15 are arranged at five locations that are half the number of poles in the circumferential direction Z, at the midpoint between the zero cross point 17 adjacent to the circumferential direction Z and the circumferential end face of the cutout portion 22. An example is considered. With such a configuration, the weld line 16 does not overlap with the cutout portion 22, thereby preventing the sensor magnet 2 from being easily broken.

  As shown in FIG. 2, the rotor core 12 and the sensor magnet 2 are fixed to each other by a resin portion 11 to form the rotor 1. The resin portion 11 is formed of, for example, a thermoplastic polybutylene terephthalate resin or a thermosetting unsaturated polyester resin. In the resin portion 11, a plurality of holes 14 where the sensor magnet 2 is exposed at one end Y1 in the axial direction Y are formed at different positions in the circumferential direction Z.

  The hole portion 14 corresponds to a portion where a reference pin 30 (see FIG. 10) to be described later, which is formed in a mold when filling the resin portion 11, is formed. In order to ensure the accuracy of the position sensor 44 described later, it is necessary to ensure the position accuracy of the sensor magnet 2 near the position of the zero cross point 17 in the axial direction Y.

  For this reason, it is desirable to arrange the reference pin 30 formed on the mold when filling the resin portion 11 at the position of the zero cross point 17 in the circumferential direction Z. That is, the hole 14 necessarily formed by the reference pin 30 is formed at the position of the zero cross point 17 in the circumferential direction Z.

  Next, a method of manufacturing the rotor 1 according to the first embodiment configured as described above will be described. First, an integral molding die is prepared, and the outer ring 5 and the inner ring 7 are arranged in the integral molding die. Then, the main magnet 9 is inserted into each of the insertion holes 61 of the outer ring 5. Next, the sensor magnet 2 is arranged so that the pin 21 of the sensor magnet 2 faces the pin insertion hole 62 of the outer ring 5. Next, the pin 21 is inserted into the pin insertion hole 62, and the sensor magnet 2 is placed on one end Y1 of the outer ring 5 in the axial direction Y.

  FIG. 11 is a cross section corresponding to the position of line AA in FIG. As shown in FIG. 11, the pin 21 of the sensor magnet 2 is inserted into a pin insertion hole 62 formed in the outer ring 5 of the rotor 1. The mounting position of the sensor magnet 2 with respect to the rotor core 12 is ensured by the pins 21. Then, the mold is closed and the inside is filled with the resin portion 11. The resin portion 11 filled in the mold covers the entirety of the sensor magnet 2 evenly while flowing through the notch portion 22 provided in the sensor magnet 2.

  The operation and effect of the cutout portion 22 and the tapered portion 23 when filling the resin portion 11 will be described with reference to FIGS. FIG. 10 is a cross-sectional view of a portion where the cutout portion 22 of the sensor magnet 2 is formed. FIG. 12 is a cross section corresponding to the position of line BB in FIG. However, FIG. 3 is a view before the resin portion 11 is formed, while FIG. 12 is a view after the resin portion 11 is formed.

  When filling the resin portion 11, the resin is filled in the direction of the arrow from the gate portion 18 shown in FIG. Then, as shown in FIG. 10, in the vicinity of the sensor magnet 2, the flow of the resin flows as shown by the arrow. Since the notch 22 is formed in the sensor magnet 2, the flow of the resin is dispersed, and before the resin is filled with excessive pressure when the resin is filled, the resin flows in the radial direction X of the sensor magnet 2. It flows outward. Therefore, it is possible to prevent the sensor magnet 2 from being broken due to an excessive load of the resin flow.

  Further, as shown in FIG. 10, the tapered portion 23 of the sensor magnet 2 is arranged so as to face the direction of the rotor 1. Therefore, the tapered portion 23 is pushed up by the resin portion 11 between the sensor magnet 2 and the rotor core 12 in a direction away from the rotor core 12 on one end side Y1 in the axial direction Y. The tapered portion 23 has a function of pushing up the sensor magnet 2 to one end Y1 in the axial direction Y by the flow of filling the resin portion 11.

  Then, one end Y1 of the sensor magnet 2 in the axial direction Y is pressed against the reference pin 30 provided on the mold and stops. Therefore, the positional accuracy of the sensor magnet 2 in the axial direction Y is ensured. As described above, even if the sensor magnet 2 floats on one end side Y1 (upper side) in the axial direction Y, the sensor magnet 2 maintains the positional relationship with the rotor core 12 by the pins 21 inserted into the pin insertion holes 62. .

  After that, the filling of the resin portion 11 is completed, and the resin portion 11 is cured. Then, a hole 14 from which the sensor magnet 2 is exposed is formed as a trace that the reference pin 30 is pressed. The holes 14, that is, the reference pins 30 are evenly arranged in the circumferential direction Z so that the pressing force applied to the sensor magnet 2 is not biased. Then, as shown in FIG. 1, the rotor 1 having the rotor core 12 and the sensor magnet 2 fixed and integrated is formed.

  Next, a rotary electric machine 100 using the rotor 1 formed as described above will be described with reference to FIGS. In FIG. 13, the rotor 1 is supported by a shaft 8 inserted into a shaft insertion hole 63 of the rotor 1 and a bearing 13 that supports the shaft 8 up and down with the rotor 1 interposed therebetween. When the rotor 1 is driven, the rotational motion is transmitted to an external device connected via the shaft 8.

  As described above, since the rotor 1 in which the rotor core 12 and the sensor magnet 2 for detecting the rotational position are integrally formed by the resin portion 11 is used, even if the rotor 1 is rotationally driven, the rotor core 12 and the sensor magnet 2 does not shift.

  As shown in FIG. 14, the stator 4 includes a stator core 40, an insulator 41, a coil 42, and a resin portion 43. A coil 42 wound on a stator core 40 via an insulator 41 is provided. These are formed by molding with a resin part 43. The rotating electric machine 100 is arranged so that the stator 4 is coaxial with the rotor 1. The external appearance of the rotating electric machine 100 is configured as shown in FIG.

  The rotary electric machine 100 is provided with a position sensor 44 for detecting the position of the rotor 1 in the rotation direction. The position sensor 44 is mounted on a sensor board 45, and the sensor board 45 is welded to a support 46. The support portion 46 is fixed by welding to the resin portion 43 of the stator 4. The support 46 is formed by injection molding a resin in a mold. If the shape of the support portion 46 is configured by appropriately setting a mold, the positional relationship of the position sensor 44 can be easily and reliably adjusted and formed. That is, it is possible to bring the position sensor 44 and the sensor magnet 2 closer to each other.

  In the first embodiment, an example is shown in which the stator 4 is combined with the rotor 1 which is an IPM rotor. However, using the same stator 4 as the configuration shown in FIG. Even if it is changed to, the positional relationship of the position sensor 44 can be effectively used, so that it can be configured as a rotating electric machine.

  Further, the example in which the rotor core 12 is formed by the outer race 5 and the inner race 7 has been described. However, the present invention is not limited to this, and the rotor core 12 is formed by one part in which the outer race 5 and the inner race 7 are integrated. Also, the sensor magnet 2 can be formed in the same manner, and the same effect can be obtained.

  Further, the example in which the tapered portion 23 is formed inside the sensor magnet 2 in the radial direction has been described. However, the present invention is not limited to this, and the tapered portion 23 is connected to the other end Y2 in the axial direction Y from one end Y1 in the axial direction Y. A tapered portion whose width in the radial direction X decreases toward the other end Y2 may be provided outside the sensor magnet 2 in the radial direction.

  Further, the example in which the sensor substrate 45 and the support portion 46 and the support portion 46 and the stator 4 are welded and fixed has been described. However, the present invention is not limited to this example. Any method and configuration, such as screwing, screwing, and bonding, can be used in the same manner, and the same effects can be obtained.

  Further, although an example is shown in which the support portion 46 is formed of resin, the present invention is not limited to this. For example, the support portion 46 may be formed of a sheet metal part formed by a press machine.

  According to the rotor and the rotating electric machine of the first embodiment configured as described above, the rotor is fixed by the integrally inserted mold while the positional relationship between the sensor magnet and the rotor core is maintained by the pin inserted into the rotor core. Therefore, the sensor magnet can be installed with excellent positional accuracy with respect to the rotor core. In addition, there is no need for an operation for separately attaching the sensor magnet and the rotor core, and no parts for the operation.

  Further, since the rotor core and the sensor magnet are integrally formed, the rotating electric machine does not rattle due to driving, so that noise during driving can be reduced.

  In addition, since the notch formed in the sensor magnet allows the resin portion filled in the mold to flow through the notch, the sensor magnet can be covered all over, and the sensor magnet is less likely to be broken.

  In addition, since a plurality of notches are formed in the circumferential direction at an intermediate position between a plurality of zero-cross points of the magnetic flux waveform of the sensor magnet, the notch is formed without lowering the position detection accuracy of the position sensor. Cracking of the sensor magnet due to pressure can be prevented.

  The sensor magnet has, on the other end side in the axial direction, a tapered portion in which the width in the radial direction decreases from one end side in the axial direction to the other end side. When the mold is filled with resin, the sensor magnet is pushed up to the other end in the axial direction, and the hole is formed by pressing against the reference pin of the mold. Is done. Thereby, the distance between the sensor magnet and the rotor core is kept constant. Therefore, the dimensional control of the distance between the sensor magnet and the position sensor for position detection becomes easy.

  Further, since the tapered portion is formed inside the sensor magnet in the radial direction, the sensor magnet is reliably pressed against the reference pin.

Also, since the hole is formed at the position of the zero cross point of the magnetic flux waveform of the sensor magnet,
The distance between the sensor magnet and the rotor core is reliably kept constant.

  The sensor magnet is formed of a plastic magnet, and the sensor magnet has a plurality of gate cut portions formed in the plastic magnet at different positions in the circumferential direction, and is located at an intermediate position between the adjacent gate cut portions in the circumferential direction. Are formed so as not to be arranged at the positions of the plurality of zero cross points of the magnetic flux waveforms of the notch and the sensor magnet, so that the weld line can be prevented from being formed at the notch and the zero cross point, and the sensor magnet can be formed. And the accuracy of position detection can be secured.

  Further, since the sensor magnet is formed radially outside the main magnet provided on the rotor core, the configuration is simplified.

  Further, since the rotor is formed of the outer ring and the inner ring disposed coaxially inside the outer ring, it is possible to suppress the electrolytic corrosion of the rotor.

  In the present invention, the embodiments can be appropriately modified and omitted within the scope of the invention.

1 rotor, 11 resin part, 12 rotor core, 13 bearing, 14 hole,
15 gate cut, 16 weld line, 17 zero cross point,
2 sensor magnet, 21 pin, 22 notch, 23 taper,
30 reference pins, 4 stators, 40 stator cores, 41 insulators,
42 coil, 43 resin part, 44 position sensor, 45 sensor board, 46 support part,
5 outer ring, 51 uneven part, 52 convex part, 53 space part, 61 insertion hole,
62 pin insertion hole, 63 shaft insertion hole, 7 inner ring, 71 uneven part, 72 concave part,
8 shaft, 9 main magnet, 100 rotating electric machine, Z circumferential direction, X radial direction,
Y-axis direction, one end of Y1 and the other end of Y2.

Claims (10)

A cylindrical rotor core,
An annular sensor magnet disposed coaxially with the rotor core on one axial end of the rotor core,
A resin portion that covers the sensor magnet and is fixed to the rotor core,
The rotor core has a plurality of pin insertion holes at different positions in the circumferential direction at one axial end, and the sensor magnet is inserted into the pin insertion hole of the rotor core at the other axial end. Multiple pins,
A rotor having a plurality of notches at different positions in a circumferential direction on the other end side in the axial direction. 2. The rotor according to claim 1, wherein the notch is formed in a circumferential direction at an intermediate position between a plurality of zero cross points of the magnetic flux waveform of the sensor magnet. 3. The sensor magnet has a tapered portion on the other end in the axial direction, the width of which in the radial direction decreases from one end in the axial direction to the other end,
3. The rotor according to claim 1, wherein the resin portion has a hole formed on one end side in the axial direction so that the sensor magnet is exposed. 4. The rotor according to claim 3, wherein the tapered portion is formed radially inside the sensor magnet. The rotor according to claim 3, wherein the hole is formed at a position of a zero cross point of a magnetic flux waveform of the sensor magnet. The sensor magnet is formed of a plastic magnet,
In the sensor magnet, a plurality of gate cut portions in the formation of the plastic magnet are formed at different positions in the circumferential direction,
6. The semiconductor device according to claim 1, wherein an intermediate position between the adjacent gate cut portions in the circumferential direction is formed so as not to be located at a plurality of zero cross points of the magnetic flux waveform of the sensor magnet. Item 2. The rotor according to item 1. The rotor according to any one of claims 1 to 6, wherein the sensor magnet is formed radially outside a main magnet installed on the rotor core. The rotor according to any one of claims 1 to 7, wherein the rotor is formed of an annular outer ring and an annular inner ring disposed coaxially with the outer ring inside the outer ring. A rotor according to any one of claims 1 to 8,
A rotating electric machine comprising the rotor and a stator arranged coaxially. The rotating electric machine according to claim 9, wherein a position sensor for detecting the position of the rotor is formed at a position facing the sensor magnet in an axial direction.

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