JP6745674B2 - Rotor and rotating electric machine - Google Patents

Description

The present invention relates to a rotor of a rotary electric machine and a rotary electric machine having a structure for fixing a sensor magnet, and particularly, the sensor magnet is hard to break, a position sensor can be easily installed, and the rotor position detection accuracy is excellent. ..

BACKGROUND ART In a conventional rotating electric machine, a rotating electric machine that mounts an embedded magnet rotor in which a magnet is embedded and realizes high efficiency and high torque is drawing attention. In the following description, an embedded magnet rotor (hereinafter referred to as "IPM rotor" using an abbreviation of Interior Permanent Magnet in English) is a rotating magnet (hereinafter referred to as "main magnet") and a rotor. And a magnet for detecting the rotational position (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" by 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 the sensor.

In recent years, in order to quickly meet customer requirements, a rotating electric machine has been developed that shares stator components and is compatible with both IPM rotors and SPM rotors. The main magnet and the sensor magnet are generally weak against tensile force and easily cracked. Therefore, when the magnet is integrally molded, it is necessary to suppress the force applied to the magnet. In particular, when the magnet receives an internal pressure, the larger the diameter is, the larger the tensile force is and the more easily the magnet is cracked.

For example, Patent Document 1 proposes a method in which a main magnet is embedded in a hole provided in a rotor core and integrally molded with resin to fix the main magnet. The sensor magnet for rotation detection is fixed to the sensor magnet supporting member and then integrally molded and fixed together with the permanent magnet. Therefore, it is a method that is easy to manufacture and assemble without requiring screws or the like.

Further, in Patent Document 1, the outer circumference of the sensor magnet is covered with resin. With this structure, since the molding pressure is applied from the outer peripheral side during molding, the force received is a compressive force and the sensor magnet is unlikely to break. The main magnet is embedded in the hole of the rotor core, and the molding pressure receives only the compressive force in the axial direction, so it is hard to crack.

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. According to this patent document 2, the end surface of the main magnet is formed into an uneven shape, a flow path for the resin is secured, and before the inner circumference of the sensor magnet is filled with the resin, the outer circumference is also filled with the resin, so that the sensor magnet is cracked. Is preventing.

Japanese Patent No. 4669734 JP, 2014-187754, A

In the conventional patent document 1, since the sensor magnet is arranged on the inner circumference side of the main magnet, the sensor for position detection must be arranged on the inner circumference 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 reduce the distance between the sensor and the sensor magnet. However, it is difficult to control the dimensions because it needs to be adjusted in the radial direction.

Further, when the sensor element is mounted on the substrate and is connected to the circuit for stabilizing the sensor signal, it is necessary to bring the substrate, which is a flat plate, closer to the inner circumference of the sensor magnet, which is a cylindrical surface. Further, when the SPM rotor and the IPM rotor are shared by the common stator, there is a problem that there is a constraint 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 the other conventional Patent Document 2, the sensor is arranged in the axial direction, but there is a problem that the material selection is limited 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 problems, and provides a rotor and a rotating electric machine in which the sensor magnet is hard to break, the position sensor can be easily installed, and the rotor position detection accuracy is excellent. The purpose is to

The rotor of this invention is
A sensor magnet provided in one end side in the axial direction and formed in an annular shape,
A cylindrical rotor core provided on the other end side in the axial direction,
A resin portion that covers the sensor magnet and is fixed to the rotor core;
The sensor magnet is formed of a plurality of divided magnets that are divided in the circumferential direction, and the plurality of divided magnets are formed by being annularly arranged in the circumferential direction,
The resin portion covers a surface of the sensor magnet on one end side in the axial direction ,
Each of the split magnets is formed between the adjacent zero cross points of the magnetic flux waveform of the sensor magnet in the circumferential direction on the other end side in the axial direction, and is more than the thickness in the axial direction at the zero cross point. Has a notch with a small axial wall thickness,
The notch portion is formed between all the adjacent zero cross points .

According to the rotor and the rotating electric machine of the present invention,
The sensor magnet is hard to break, the position sensor can be easily installed, and the rotor position detection accuracy is excellent.

It is a top view which shows the structure of the rotor of Embodiment 1 of this invention. It is a cross-sectional side view which shows typically the internal structure in the TT line of the rotor shown in FIG. It is a cross-sectional side view which shows typically the internal structure in the HH line of the rotor shown in FIG. FIG. 2 is a top view showing a configuration of an outer ring of the rotor core shown in FIG. 1. It is a top view which shows the structure of the inner ring of the rotor core shown in FIG. 5 is a perspective view showing a configuration of a main magnet housed in an outer ring of the rotor core shown in FIG. 4. FIG. It is a perspective view which shows the structure of the sensor magnet of the rotor shown in FIG. FIG. 8 is a top view showing the configuration of one split magnet that constitutes the sensor magnet of the rotor shown in FIG. 7. FIG. 9 is a side view showing the configuration of the split magnet shown in FIG. 8. It is a perspective view which shows the structure of the division magnet shown in FIG. FIG. 16 is a diagram for explaining a magnetic flux distribution of a sensor magnet passing in the Q direction of the rotor shown in FIG. 15 and a configuration of the sensor magnet. FIG. 3 is a cross-sectional view for explaining the flow of resin around the sensor magnet shown in FIG. 2. 5 is a cross-sectional view illustrating a relationship between a rotor core and a pin in a cross section taken along the line AA of the outer ring of the rotor core illustrated in FIG. 4. FIG. 5 is a cross-sectional view illustrating the relationship between the rotor core and the tapered portion in the cross section taken along the line BB of the outer ring of the rotor core shown in FIG. 4. It is explanatory drawing which shows typically the attachment structure of the rotor shown in FIG. It is sectional drawing which shows the structure of the rotary electric machine using the rotor shown in FIG. It is a perspective view which shows the external appearance of the rotary electric machine shown in FIG. It is a perspective view which shows the structure of the rotor except the resin part for demonstrating arrangement|positioning of the sensor magnet shown in FIG. It is a perspective view which shows the structure of the rotor shown in FIG. It is a top view which shows the structure of one split magnet of another example which comprises the sensor magnet of the rotor shown in FIG. It is a side view which shows the structure of the division magnet shown in FIG. It is a perspective view which shows the structure of the division magnet shown in FIG. It is a perspective view which shows the structure of the rotor except the resin part for demonstrating arrangement|positioning of the division magnet shown in FIG.

Embodiment 1.
Hereinafter, embodiments of the present invention will be described. The rotor 1 according to the first embodiment will be an IPM rotor. 1 is a plan view showing the structure of a rotor according to a first embodiment of the present invention. FIG. 2 is a cross-sectional side view for schematically explaining the internal structure of the rotor shown in FIG. 1 along the line TT. FIG. 3 is a cross-sectional side view for schematically explaining the internal structure along the line HH of the rotor shown in FIG. FIG. 4 is a top view showing the structure of the outer ring of the rotor core shown in FIG. FIG. 5 is a top view showing the structure of the inner ring of the rotor core shown in FIG.

FIG. 6 is a perspective view showing the structure of the main magnet housed in the outer ring of the rotor core shown in FIG. FIG. 7 is a perspective view showing the configuration of the sensor magnet of the rotor shown in FIG. FIG. 8 is a top view showing the configuration of one split magnet that constitutes the sensor magnet shown in FIG. FIG. 9 is a side view showing the configuration of the split magnet shown in FIG. FIG. 10 is a perspective view showing the structure of the split magnet shown in FIG. FIG. 11 is a diagram for explaining the magnetic flux distribution of the sensor magnet passing in the Q direction of the rotor shown in FIG. 15 and the configuration of the sensor magnet.

FIG. 12 is a sectional view for explaining the flow of resin around the sensor magnet shown in FIG. FIG. 13 is a cross-sectional view illustrating the relationship between the rotor core and the pins in the cross section taken along the line AA of the outer ring of the rotor core shown in FIG. FIG. 14 is a cross-sectional view illustrating the relationship between the rotor core and the tapered portion in the cross section taken along the line BB of the outer ring of the rotor core shown in FIG. FIG. 15 is an explanatory view schematically showing the mounting structure of the rotor shown in FIG. FIG. 16 is a cross-sectional view showing the configuration of a rotary electric machine using the rotor shown in FIG. FIG. 17 is a perspective view showing the external appearance of the rotary electric machine shown in FIG. FIG. 18 is a perspective view showing the configuration of the rotor excluding the resin portion for explaining the arrangement of the sensor magnet shown in FIG. 19 is a perspective view showing a configuration of the rotor shown in FIG. 1, that is, a perspective view showing a configuration after the resin portion is installed in FIG.

1 to 4, the rotor 1 includes a rotor core 12, a sensor magnet 2, and a resin portion 11. The rotor core 12 is composed of an outer ring 5, an inner ring 7, and a main magnet 9. The sensor magnet 2 is formed in an annular shape coaxial with the rotor core 12 on one end side Y1 of the rotor core 12 in the axial direction Y. The sensor magnet 2 is arranged outside the main magnet 9 installed in the rotor core 12 in the radial direction X. The sensor magnet 2 detects the rotational position of the rotor core 12. The rotor core 12 and the sensor magnet 2 are integrally fixed by the resin portion 11.

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

As shown in FIG. 4, the outer race 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 positions in the circumferential direction Z, and here, an example in which the number of poles is 10 is shown, and the insertion holes 61 are formed at 10 positions at equal intervals in the circumferential direction Z. Although the number of poles is 10 in the example, the number of poles is not limited to this, and other numbers of poles can be similarly formed.

The pin insertion hole 62 is a hole that is formed continuously at both ends of each insertion hole 61. The pin insertion hole 62 is a hole for inserting each pin 21 of the split magnet 20 constituting the sensor magnet 2 described later, and is formed at a position corresponding to each pin 21 of the split magnet 20. Although the pin insertion hole 62 has been shown as an example formed in communication with the insertion hole 61, the pin insertion hole 62 is not limited to this and may be formed as a hole different from the insertion hole 61 as appropriate.

The space portion 53 is a circular space formed in the 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 positions in the circumferential direction Z and at different positions in the radial direction X. The concavo-convex portion 51 is used for caulking and fixing when the thin outer rings 5 are stacked. A plurality of convex portions 52 are formed so as to protrude inward in the radial direction X at different locations in the circumferential direction Z on the inner circumference of the outer ring 5 in the radial direction X.

As shown in FIG. 5, the inner ring 7 includes a shaft insertion hole 63, an uneven portion 71, and a recess 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 the shaft 8 described later. A plurality of uneven portions 71 are formed at different positions in the circumferential direction Z. The concavo-convex portion 71 is used for caulking and fixing when laminating the inner races 7 of thin plates. A plurality of recesses 72 are formed on 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 convex portion 52 of the outer ring 5 and the concave portion 72 of the inner ring 7 are engaged with each other. The action of the rotating torque prevents the outer ring 5 and the inner ring 7 from being displaced. Then, the rotor core 12 is formed by inserting the main magnet 9 shown in FIG. 6 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 race 5 and the inner race 7, electrolytic corrosion of the rotor 1 is suppressed. Further, as shown in FIG. 6, the main magnet 9 can be formed in a simple shape, and there is no restriction on material selection.

As shown in FIG. 7, the sensor magnet 2 is formed by arranging five divided magnets 20 which are divided in the circumferential direction Z in an annular shape. Between each of the divided magnets 20, there is a gap portion 19 as a divided position formed by the division. Then, as shown in FIGS. 8, 9, and 10, one split magnet 20 constituting the sensor magnet 2 includes a pin 21, a cutout portion 22, and a taper portion 23. The pin 21 is formed at two different positions in the circumferential direction Z so as to project to the other end side Y2 in the axial direction Y. Moreover, the pin 21 is formed in an approximate cylindrical shape.

The number of pins 21 formed on one split magnet 20 may be any number that enables positioning when the sensor magnet 2 of the rotor 1 is installed, and may be three, four or more. , But not limited to. However, considering the easiness of performing the assembling process, two pieces are most desirable. The pin 21 may have a shape other than a cylindrical shape, and may be formed in a conical shape or a triangular prism shape, for example. However, if the pin 21 has a corner, cracks or chips may occur, so a shape with rounded corners is desirable.

The cutout portion 22 is formed on the other end side 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 as a recess in one end Y1 in the axial direction Y at different positions in the circumferential direction Z as a whole of the sensor magnet 2. The cutouts 22 are formed in the sensor magnet 2 as a whole at ten positions in the circumferential direction Z at equal intervals in the same number as the number of poles. The cutout portion 22 is formed for the purpose of improving the fluidity of the resin portion 11 when the rotor core 12 and the sensor magnet 2 including the split magnet 20 are fixed to each other.

The taper portion 23 is formed on the inner peripheral side of the sensor magnet 2 constituted by the split magnets 20 on the other end side Y2 in the same direction as the pin 21 is formed in the axial direction Y. The taper portion 23 has a shape in which the width in the radial direction X decreases from one end side Y1 in the axial direction Y toward the other end side Y2 where the pin 21 is formed (particularly, see FIGS. 12 to 13). The sensor magnet 2 including the split magnets 20 is arranged such that the other end side Y2 in the axial direction Y on which the pin 21 is formed faces the upper surface of the rotor core 12. Then, the pin 21 is inserted into the pin insertion hole 62 formed in the outer ring 5.

As described above, the sensor magnet 2 including the split magnets 20 has a complicated shape such as the notch portion 22 and the taper portion 23. For this reason, in order to manufacture efficiently, a plastic magnet material (resin magnet material) that can be mixed with resin and magnetic material and molded with a die is used as the material. Further, since the sensor magnet 2 is composed of a plurality of divided magnets 20, it is possible to reduce the mold size and reduce the mold cost as compared with the sensor magnet formed in one annular shape. it can. Further, since the five divided magnets 20 are formed in the same shape, they can be manufactured with one type of die, and the die cost can be reduced.

Here, details of the formation position of the cutout portion 22 of the sensor magnet 2 and the formation position of the gap portion 19 of the divided magnet 20 of the sensor magnet 2 will be described with reference to FIG. 11. FIG. 11 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. 15 and a developed view showing the sensor magnet 2 in a portion corresponding to the magnetic flux distribution in an expanded manner. In the figure showing the magnetic flux distribution, the horizontal axis is the position in the rotation direction of the rotor 1, and any one point is set to 0 degree, and the magnetic field is expanded in the circumferential direction up to 360 degrees. The vertical axis represents the amount of magnetic flux at each position.

A position sensor 44, which will be described later, for detecting the position of the rotor 1 detects a point 17 (hereinafter referred to as a zero cross point 17) at which the N pole and the S pole of the magnetic flux of the sensor magnet 2 are switched, as shown in FIG. 11. Therefore, the notch 22 needs to be formed at a position that does not overlap 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 the positions of the plurality of zero cross points 17 of the magnetic flux waveform of the sensor magnet 2.

This is because the sensor magnet 2 is formed such that the wall thickness of the sensor magnet 2 near the position of the zero-cross point 17 is increased, and a sufficient amount of magnetic flux near the position of the zero-cross point 17 is secured. By thus securing the amount of magnetic flux, the position detection accuracy of the position sensor 44 is increased. Therefore, the notch 22 where the wall thickness of the sensor magnet 2 becomes thin must be formed at a position that does not overlap the position of the zero cross point 17.

Further, the gap portion 19 formed between the adjacent divided magnets 20 is installed in the circumferential direction Z at an intermediate position (center position of the magnetic pole) of the positions of the plurality of zero cross points 17 of the magnetic flux waveform of the sensor magnet 2. .. Similar to the arrangement of the cutout portion 22, this is formed so that the wall thickness of the sensor magnet 2 near the position of the zero cross point 17, that is, the split magnet 20, is thickened to secure a sufficient magnetic flux amount near the position of the zero cross point 17. This is because By thus securing the amount of magnetic flux, the position detection accuracy of the position sensor 44 is increased.

Therefore, the gap portion 19 which is a portion where the split magnet 20 does not exist needs to be formed at a position that does not overlap the position of the zero cross point 17. The size of the gap portion 19 in the circumferential direction Z is shown as an example to have a certain size (space) for convenience of explanation, but the size of the gap portion 19 in the circumferential direction Z is not limited to this. However, the size is not limited to the above, as long as the divided magnets 20 do not collide with each other and the sensor magnet 2 formed by the divided magnets 20 can be used.

As shown in FIGS. 2 and 3, the rotor core 12 and the sensor magnet 2 are fixed to each other by the resin portion 11 to form the rotor 1. The resin portion 11 is formed of, for example, a thermoplastic polybutylene terephthalate resin, a thermosetting unsaturated polyester resin, or the like. The resin portion 11 is provided with a plurality of hole portions 14 in which the divided magnets 20 are exposed at one end Y1 in the axial direction Y at different positions in the circumferential direction Z. Here, two holes 14 are formed for each split magnet 20.

The hole portion 14 corresponds to a portion where a reference pin 30 (see FIG. 12), which will be described later, is formed in the mold when the resin portion 11 is filled. In order to secure the accuracy of the position sensor 44, which will be described later, it is necessary to secure the positional accuracy in the axial direction Y of each split magnet 20 near the position of the zero cross point 17.

Therefore, it is desirable to dispose the reference pin 30 formed in the mold when the resin portion 11 is filled at the position of the zero cross point 17 in the circumferential direction Z. That is, the hole portion 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 of the first embodiment configured as described above will be described. In the following description, the sensor magnet 2 composed of the split magnets 20 may be simply referred to as the sensor magnet 2. 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 five split magnets 20 are annularly arranged in the pin insertion holes 62 of the outer ring 5 so that the pins 21 of the split magnets 20 face each other. Next, the pin 21 of each split magnet 20 is inserted into the pin insertion hole 62, and as shown in FIG. 18, the sensor magnet 2 composed of five split magnets 20 on one end side Y1 of the outer ring 5 in the axial direction Y. Place as.

FIG. 13 is a cross section corresponding to the position of line AA in FIG. As shown in FIG. 13, the pin 21 of each split magnet 20 is inserted into the pin insertion hole 62 formed in the outer ring 5 of the rotor 1. The pin 21 ensures the attachment position of the sensor magnet 2 constituted by the split magnet 20 to the rotor core 12. Then, the mold is closed and the inside is filled with the resin portion 11. The resin portion 11 filled in the mold flows uniformly through the cutout portion 22 formed in the sensor magnet 2 constituted by the split magnets 20 and uniformly covers the entire sensor magnet 2.

The action and effect of the cutout portion 22 and the taper portion 23 when the resin portion 11 is filled will be described with reference to FIGS. 12 and 14. FIG. 12 is a cross-sectional view of a portion where the cutout portion 22 of the sensor magnet 2 including the split magnet 20 is formed. FIG. 14 is a cross section corresponding to the position of line BB in FIG. However, while FIG. 4 is a diagram before the resin portion 11 is formed, FIGS. 13 and 14 are diagrams after the resin portion 11 is formed.

When the resin portion 11 is filled, the resin is filled from the gate portion 18 shown in FIG. 14 in the direction of the arrow. Then, as shown in FIG. 12, in the vicinity of the sensor magnet 2, the flow of resin flows as indicated by the arrow. Since the notch 22 is formed in the sensor magnet 2, the resin flows in the radial direction X of the sensor magnet 2 before the resin flow is dispersed and excessive pressure is applied to the sensor magnet 2 when the resin is filled. Flowing to the outside. Therefore, it is possible to prevent the sensor magnet 2 from being cracked due to an excessive load of the resin flow. Further, since the sensor magnet 2 is composed of the plurality of divided magnets 20, the tensile force generated by the molding pressure can be reduced.

Further, as shown in FIG. 12, the taper portion 23 of the sensor magnet 2 composed of the split magnets 20 is arranged so as to face the rotor 1. Therefore, the taper portion 23 is pushed up by the resin portion 11 between the sensor magnet 2 and the rotor core 12 in the direction Y1 in the axial direction Y, that is, in the direction away from the rotor core 12. The taper portion 23 has a function of pushing up the sensor magnet 2 to the one end side Y1 in the axial direction Y by the flow filled with the resin portion 11.

Then, one end side Y1 of each split magnet 20 in the axial direction Y is pressed against the reference pin 30 provided on the mold and stopped. Therefore, the positional accuracy of the sensor magnet 2 constituted by the split magnets 20 in the axial direction Y is ensured. In this way, even if the sensor magnet 2 composed of the split magnets 20 floats up to the one end side Y1 (upper side) in the axial direction Y, the sensor magnet 2 composed of the split magnets 20 is inserted into the pin insertion hole 62. The inserted pin 21 maintains the positional relationship with respect to the rotor core 12.

Then, the filling of the resin portion 11 is completed and the resin portion 11 is cured. Then, as a trace of the reference pin 30 being pressed, the hole portion 14 exposing each split magnet 20 is formed. The holes 14, that is, the reference pins 30 are evenly arranged with respect to the divided magnets 20 in the circumferential direction Z so that the pressing force applied to the divided magnets 20 is not biased. Then, as shown in FIG. 1 and FIG. 19, the rotor 1 in which the rotor core 12 and the sensor magnet 2 constituted by the split magnet 20 are fixed and integrated is formed.

Next, a rotating electric machine 100 using the rotor 1 thus formed will be described with reference to FIGS. 15 to 17. In FIG. 15, the rotor 1 is supported by a shaft 8 that is inserted into the shaft insertion hole 63 of the rotor 1 and a bearing 13 that vertically supports the shaft 8 with the rotor 1 interposed therebetween. When the rotor 1 is driven, the rotational movement is transmitted to the external device connected via the shaft 8.

As described above, since the rotor core 12 and the sensor magnet 2 including the divided magnet 20 for detecting the rotational position are integrally molded by the resin portion 11, the rotor 1 is rotationally driven. However, the rotor core 12 and the sensor magnet 2 including the split magnets 20 are not displaced.

Then, as shown in FIG. 16, the stator 4 includes a stator core 40, an insulator 41, a coil 42, and a resin portion 43. A coil 42 wound around an insulator 41 is installed on the stator core 40. Then, these are molded by the resin portion 43. The rotating electric machine 100 is arranged so that the stator 4 is coaxial with the rotor 1. The external appearance of the rotary electric machine 100 is configured as shown in FIG.

The rotary electric machine 100 is provided with a position sensor 44 that detects the position of the rotor 1 in the rotation direction. The position sensor 44 is mounted on the sensor substrate 45, and the sensor substrate 45 is welded to the support portion 46. The supporting portion 46 is welded and fixed to the resin portion 43 of the stator 4. The support portion 46 is formed by injection molding a resin in a mold. The shape of the supporting portion 46 can be formed by adjusting the position of the position sensor 44 easily and surely by appropriately setting a mold. That is, it is possible to bring the position sensor 44 and the sensor magnet 2 constituted by the split magnets 20 closer to each other before they interfere with each other.

In the above-described embodiment, the example in which the sensor magnet 2 is composed of the five divided magnets 20, which is a divisor of the number of poles of the sensor magnet 2, has been shown, but the present invention is not limited to this and other numbers may be used. However, it can be set appropriately. As another example, an example in which the sensor magnet 2 is composed of ten divided magnets 25, which is a divisor of the number of poles, will be described. For example, FIG. 20 shows a top view of the structure of a split magnet showing another example of the rotor shown in FIG. FIG. 21 is a side view showing the configuration of the split magnet of another example shown in FIG. 22 is a perspective view showing the structure of another example of the split magnet shown in FIG. FIG. 23 is a perspective view showing a configuration in which a resin portion is removed from the rotor for explaining the arrangement of the ten divided magnets of the other example shown in FIG.

In the figure, the same parts as those in the first embodiment described above are designated by the same reference numerals and the description thereof is omitted. The sensor magnet 2 is composed of ten divided magnets 25. Then, two pins 21, a notch portion 22 and a taper portion 23 are formed in each split magnet 25 as in the first embodiment. FIG. 23 shows a state where the ten divided magnets 25 are inserted into the pin insertion holes 62 of the outer ring 5. In this way, by arranging the ten divided magnets 25 in the annular direction in the circumferential direction Z, the sensor magnet 2 configured by the divided magnets 25 is configured as in the first embodiment. Further, at this time, the gap portion 19 is formed at a position different from the zero cross point 17 as in the first embodiment.

As described above, if the divided magnets 20 and 25 are formed by the number of poles of the sensor magnet 2, the divided magnets 20 and 25 can be formed in the same structure. Can be formed into a mold and can be manufactured at low cost.

Further, in the above-described first embodiment, an example in which the stator 4 is combined with the rotor 1 which is an IPM rotor has been shown. However, using the same stator 4 having the configuration shown in FIG. Even if it is changed to, the positional relationship of the position sensor 44 can be effectively used, and the magnetic flux of the main magnet attached to the outer circumference can be read as it is, so that it can be configured as a rotary electric machine.

Further, although the example in which the rotor core 12 is formed by the outer ring 5 and the inner ring 7 is shown, the invention is not limited to this, and the rotor core 12 is formed by one part in which the outer ring 5 and the inner ring 7 are integrated. However, the sensor magnet 2 including the split magnets 20 can be formed in the same manner, and the same effect can be obtained.

Further, although the taper portion 23 is shown as an example of being formed on the inner side in the radial direction of the sensor magnet 2 constituted by the split magnets 20, the present invention is not limited to this, and the other end side Y2 in the axial direction Y may have A taper portion whose width in the radial direction X decreases from the one end side Y1 in the direction Y toward the other end side Y2 may be provided outside the sensor magnet 2 in the radial direction.

Further, an example in which the sensor substrate 45 and the supporting portion 46, and the supporting portion 46 and the stator 4 are welded and fixed has been shown, but the present invention is not limited to this, and any method of fixing flat surfaces to each other may be used. The same effect can be obtained by using any method and structure such as fixing with screws, bonding, or the like.

Further, although an example in which the support portion 46 is formed of resin is shown, the support portion 46 is not limited to this, and may be formed of, for example, 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 sensor magnet is formed of a plurality of divided magnets that are divided in the circumferential direction, so that the mold can be downsized. It can be manufactured at low cost. Further, since the resin portion is divided and formed in advance, it is possible to reduce the tensile force generated by the molding pressure when the resin portion is formed. Therefore, it is possible to prevent cracks occurring in unnecessary portions of the sensor magnet.

In addition, the gap between the split magnets is formed at an intermediate position between the positions of the multiple zero cross points, which is a position different from the zero cross point of the magnetic flux waveform of the sensor magnet configured by the split magnets in the circumferential direction. It is possible to prevent cracking of the sensor magnet composed of the split magnets due to molding pressure without lowering the position detection accuracy of the sensor.

Further, since the split magnets are formed in a number that is a divisor of the number of magnetic poles, the split magnets can be formed in the same shape, and can be manufactured with one type of die, resulting in low cost. Can be manufactured at.

Also, since the pin of the split magnet is installed in the pin insertion hole formed in the rotor core, the sensor magnet is fixed to the rotor core by the integral molding die while maintaining the positional relationship between the sensor magnet and the rotor core. On the other hand, it can be installed with excellent positional accuracy. Further, the work of individually attaching the split magnet and the rotor core, and the parts for that are unnecessary. Further, since the split magnet has two pins, it can be securely mounted on the rotor core and can be formed with a simple structure.

Further, since the rotor core and the sensor magnet are integrally molded, the rotating electric machine does not cause rattling due to driving, and thus noise during driving can be reduced.

In addition, since the resin portion filled in the mold flows through the notch portion by the notch portion formed in the sensor magnet formed of the split magnets, the sensor magnet can be covered all over, and the sensor magnet Is hard to crack.

Further, since the notch is formed in the circumferential direction at a position intermediate between the positions of a plurality of zero cross points of the magnetic flux waveform of the sensor magnet configured by the split magnet, the position detection accuracy of the position sensor is improved. It is possible to prevent the sensor magnet from cracking due to the molding pressure without lowering the pressure.

The sensor magnet composed of split magnets has a taper portion on the other end side in the axial direction whose radial width decreases from one end side in the axial direction to the other end side, and one end in the axial direction of the resin part. The end face on the side has a hole that exposes the part corresponding to each split magnet, so when the mold is filled with the resin part, each split magnet is pushed up to the other end side in the axial direction, and A hole is formed by being pressed against the reference pin of the mold. As a result, the distance between the sensor magnet composed of the split magnets and the rotor core is kept constant. Therefore, it becomes easy to manage the dimension of the distance between the sensor magnet composed of the divided magnets and the position sensor for position detection.

Further, since the taper portion is formed on the inner side in the radial direction of the sensor magnet composed of the split magnets, it can be reliably pressed against the reference pin against each split magnet.

Moreover, 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 can be reliably kept constant.

Further, since the sensor magnet configured by the split magnets is formed radially outside the main magnet installed in the rotor core, the configuration becomes simple.

Moreover, since the rotor is formed of the outer ring and the inner ring coaxially arranged inside the outer ring, electrolytic corrosion of the rotor can be suppressed.

The present invention can appropriately modify or omit the embodiments within the scope of the invention.

1 rotor, 11 resin part, 12 rotor core, 13 bearing, 14 hole part,
17 zero cross points, 18 gates, 19 gaps, 2 sensor magnets,
20 split magnets, 21 pins, 22 notches, 23 taper,
25 split magnets, 30 reference pins, 4 stators, 40 stator cores,
41 insulator, 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 portion, 61 insertion hole, 62 pin insertion hole, 63 shaft insertion hole, 7 inner ring,
71 convexoconcave portion, 72 concave portion, 8 shaft, 9 main magnet, 100 rotating electric machine, Z circumferential direction, X radial direction, Y axial direction, Y1 one end side, Y2 other end side.

Claims (13)

A sensor magnet provided in one end side in the axial direction and formed in an annular shape,
A cylindrical rotor core provided on the other end side in the axial direction,
A resin portion that covers the sensor magnet and is fixed to the rotor core;
The sensor magnet is formed of a plurality of divided magnets that are divided in the circumferential direction, and the plurality of divided magnets are formed by being annularly arranged in the circumferential direction,
The resin portion covers a surface of the sensor magnet on one end side in the axial direction ,
Each of the split magnets is formed between the adjacent zero cross points of the magnetic flux waveform of the sensor magnet in the circumferential direction on the other end side in the axial direction, and is more than the axial wall thickness at the zero cross point. Has a notch with a small axial wall thickness,
The notch portion is a rotor formed between all the adjacent zero cross points . The rotor according to claim 1, wherein circumferentially divided positions of the plurality of divided magnets are formed at positions different from a plurality of zero cross points of a magnetic flux waveform of the sensor magnet in the circumferential direction. The rotor according to claim 1, wherein the sensor magnet is formed of the divided magnets whose number is a divisor of the number of magnetic poles. 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,
The rotor according to any one of claims 1 to 3 , wherein each of the split magnets has a pin that is inserted into the pin insertion hole of the rotor core on the other end side in the axial direction. The rotor according to claim 4 , wherein each of the split magnets includes two pins. The notch portion is provided such that the outside in the radial direction is recessed toward the one end side in the axial direction at the other end side in the axial direction of the sensor magnet.
The rotor according to any one of claims 1 to 5 . Each of the split magnets has, on the other end side in the axial direction, a taper portion whose width in the radial direction decreases from one end side in the axial direction to the other end side,
The rotor according to any one of claims 1 to 6 , wherein the resin portion has a hole portion formed on one end side in the axial direction to expose each of the split magnets. The rotor according to claim 7 , wherein the hole is formed at positions of a plurality of zero cross points of a magnetic flux waveform of the sensor magnet in the circumferential direction. The rotor according to claim 7 , wherein the tapered portion is formed inside a radial direction of each of the split magnets. The rotor is formed from an annular outer ring and an annular inner ring arranged inside the outer ring coaxially with the outer ring,
The resin portion covers a surface on one end side and the surface on the other end side in the axial direction of the outer ring, and is in contact with the radially inner surface of the outer ring and the radially outer surface of the inner ring to be integrally formed. The rotor according to any one of claims 1 to 9 , which is provided as a rotor. The divided magnet rotor according to any one of claims 1 to 10, which are formed by plastic magnet material. A rotor according to any one of claims 1 to 11 ,
A rotating electric machine comprising: the rotor and a stator arranged coaxially. The rotary electric machine according to claim 12 , wherein a position sensor that detects the position of the rotor is formed at a position that faces a surface of the sensor magnet on one end side in the axial direction in the axial direction.

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