Rotor, motor using same, and electronic device

Abstract

The invention provides a rotor, a motor using the rotor, and an electronic device. The rotor can effectively utilize magnetic flux generated by a magnet. The rotor is provided with: a rotor core (33) having an annular part (33a) and a plurality of magnetic pole pieces (33b) radially extending from the annular part (33a) through a pair of connecting parts (33c, 33c); a plurality of first magnets (31) disposed between the magnetic pole pieces (33b) adjacent to each other in the circumferential direction; and a plurality of second magnets (32) disposed between the pair of connecting portions (33c, 33c), each first magnet (31) being in contact with the side surfaces (32i, 32i) of two adjacent pole pieces (33b) in the circumferential direction, and the second magnets (32) being in contact with the inner surfaces (32g) of the pole pieces (33b) in the radial direction.

Description

This application is a divisional application of a patent application with application number 201980077391.8, application date August 19, 2019, and invention name “rotor, motor using the rotor, and electronic device”. Technical Field

[0001] The present invention relates to a rotor, a motor using the rotor, and an electronic device. Background Art

[0002] In the past, motors were used as drive sources in various devices. There are many types of motors, and various motors are selected according to the purpose and scene of use. Among them, the IPM (Interior Permanent Magnet) motor that actively uses reluctance torque has high efficiency and can achieve high torque. IPM motors are disclosed in Patent Documents 1 and 2, for example.

[0003] However, in the technology described in Patent Document 1, the radially arranged pole pieces on the rotor core are in a state of being supported by thin connecting portions between adjacent magnetic isolation portions on an annular portion at the center of the rotor core, making it difficult to ensure strength. Furthermore, due to the force (centrifugal force or magnetic force) acting on the pole pieces when the motor is driven, the pole pieces are likely to vibrate or shift, thereby causing noise, rotor damage and other adverse conditions.

[0004] In addition, in the technology described in Patent Document 2, although the rigidity can be ensured to a certain extent, the magnet is long in the radial direction of the rotor, so in the area of ​​the magnetic pole surface that is far away from the outer periphery of the rotor, the magnetic flux is difficult to be directed toward the outer periphery, and the magnetic flux cannot be effectively used. Therefore, even if a relatively large magnet is used to obtain a larger magnetic pole surface, the efficiency that matches the size cannot be obtained, and on the contrary, since a larger magnetic pole surface must be ensured, it is impossible to achieve miniaturization of the motor. (Prior art literature) (Patent Document)

[0005] Patent Document 1: Japanese Patent Application Publication No. 2015-177721 Patent Document 2: Japanese Patent Application Publication No. 2015-211623 Summary of the invention (Problems to be solved by the invention)

[0006] Therefore, the present invention has been made in view of the above background, and an object of the present invention is to provide a rotor capable of effectively utilizing magnetic flux generated from a magnet, and a motor and an electronic device using the rotor. (Technical solutions to solve problems)

[0007] The above-mentioned problems are solved by the following present invention. That is, the rotor of the present invention comprises: a rotor core having an annular portion and a plurality of magnetic pole pieces radially extending from the annular portion through a pair of connecting portions; a plurality of first magnets arranged between the magnetic pole pieces adjacent to each other in the circumferential direction; and a plurality of second magnets arranged between the pair of connecting portions, wherein each of the first magnets contacts the side surfaces of two adjacent magnetic pole pieces in the circumferential direction and the second magnets contact the inner surfaces of the magnetic pole pieces in the radial direction.

[0008] In the rotor of the present invention, the pole of the first magnet located on one of the two side surfaces of the pole piece in the circumferential direction, the pole of the first magnet located on the other side surface of the two side surfaces in the circumferential direction, and the pole of the second magnet located on the inner surface side of the pole piece in the radial direction are the same poles.

[0009] In the rotor of the present invention, preferably, a first gap is provided between the inside of the first magnet and the outer surface of the annular portion in the radial direction. In this case, the width of the first gap in the circumferential direction can be set to increase from the annular portion toward the magnetic pole piece.

[0010] In the rotor of the present invention, preferably, a second gap is provided between both side surfaces of the second magnet and side surfaces of the pair of connection portions in the circumferential direction. In this case, the width of the second gap in the circumferential direction can be set to become narrower from the annular portion toward the magnetic pole piece.

[0011] In addition, at this time, preferably, the corner of the second magnet contacts the corner on the magnetic pole piece side among the plurality of corners of the second gap. Furthermore, at this time, among the plurality of corners of the second gap, the corner on the annular portion side can be separated from the corner of the second magnet.

[0012] Furthermore, in the rotor of the present invention, preferably, an inner surface of the second magnet is in contact with an outer surface of the annular portion in a radial direction. In addition, in the rotor of the present invention, it is possible that, in the radial direction, the outer surface of the second magnet and the inner surface of the pole piece are curved toward the outside of the rotor.

[0013] Furthermore, in the rotor of the present invention, the inner surface of the second magnet and the outer surface of the annular portion may be curved in the radial direction toward the hole portion of the annular portion. Furthermore, in the rotor of the present invention, preferably, the width of the connection portion in the circumferential direction becomes narrower from the annular portion toward the pole piece.

[0014] On the other hand, a motor of the present invention includes: the rotor of the present invention described above; a shaft fixed to the rotor; and a stator having a coil and a magnetic body around which the coil is wound. Furthermore, an electronic device according to the present invention includes the motor according to the present invention described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a longitudinal sectional view of a motor using a rotor according to an embodiment of the present invention, Figure 2 BB section view in. Figure 2 is a cross-sectional view of a motor using a rotor according to an embodiment of the present invention, Figure 1 AA section view in. Figure 3 It is a partially enlarged cross-sectional view of a rotor according to one embodiment of the present invention. Figure 4 This is a schematic diagram simulating how magnetic flux from a magnet draws magnetic lines of force in a rotor core in a conventional rotor that does not have a second magnet. Figure 5 This is a schematic diagram simulating how magnetic flux from the magnets draws magnetic lines of force in the rotor core in this embodiment. Figure 6 The connecting portion and its surroundings in the rotor of one embodiment of the present invention ( Figure 2 A partial enlarged view of the area in C). Figure 7 This is a partially enlarged cross-sectional view of a rotor according to a first modified example as one example of the present invention. Figure 8 This is a partially enlarged cross-sectional view of a rotor according to a second modified example as an example of the present invention. Fig. 9 This is a partially enlarged cross-sectional view of a rotor according to a third modified example as an example of the present invention. Fig.10 This is a partially enlarged cross-sectional view of a rotor according to a fourth modified example as an example of the present invention. Fig.11 The connecting portion and its surroundings in the rotor of the fourth modified example as one example of the present invention ( Fig.10 A partial enlarged view of the area in (E). DETAILED DESCRIPTION

[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Figure 1 is a longitudinal sectional view of a motor 1 using a rotor 3 as an example embodiment of the present invention, Figure 2 It is a cross-sectional view. Figure 1 Equivalent to Figure 2 BB section view in Figure 2 Equivalent to Figure 1 AA section view in.

[0017] In the description of this embodiment, the terms "upper" and "lower" refer to Figure 1 The up-down relationship in the direction of gravity is not consistent with the up-down relationship in the direction of gravity. The motor 1 in the present embodiment is a kind of inner rotor type brushless motor, and is a spoke type IPM motor.

[0018] An IPM motor is a motor in which magnets are embedded in a rotor, and is also called an embedded magnet motor. IPM motors also have various forms, and a spoke-type IPM motor is known in which magnets with rectangular cross-sections are radially arranged in the long side direction in the rotor core. In this spoke-type motor, the surface on the long side becomes a magnetic pole, and the opposing magnetic pole surfaces of adjacent magnets in the circumferential direction become the same pole.

[0019] In this IPM motor, if magnetic flux short-circuits inside the rotor, the average magnetic flux density decreases, resulting in a decrease in efficiency. Therefore, in a spoke-type IPM motor, a magnetic shielding portion is formed by providing a gap in the rotor core, and the operating efficiency is improved by directing the magnetic flux as much as possible toward the stationary portion.

[0020] The motor 1 includes: a shaft 2 serving as a rotating shaft; a rotor 3 formed by arranging magnets 31 and 32 in a rotor core 33 formed by a magnetic body, and fixed to the shaft 2 so as to rotate together with the shaft 2; a stator 4 formed by winding a coil 42 around a stator core 41 formed by a magnetic body, and arranged so as to surround the rotor 3; and a housing 5 to which the stator 4 is fixed and which accommodates part or all of the components of the motor 1 inside.

[0021] The housing 5 includes: a housing body 51 that houses part or all of the components of the motor 1 such as the rotor 3 and the stator 4, and fixes the stator 4 therein; and a cover 52 that covers the opening provided at the top of the housing body 51. The housing body 51 includes a bottom 51a, a cylinder 51b, and an outer peripheral portion 51c, wherein the bottom 51a includes a protruding portion 51aa described later. The cover 52 includes an annular flat plate portion 52a and an outer peripheral portion 52c, wherein the flat plate portion 52a includes a protruding portion 52aa described later. The protruding portion 52aa of the cover 5 is provided on the flat plate portion 52a, and protrudes in the direction of the rotor 3 in the long side direction of the shaft 2. By fixing (fastening) the outer peripheral portion 51c of the housing body 51 and the outer peripheral portion 52c of the cover 52, the inside of the housing 5 is shielded from the outside, and the motor 1 is completed.

[0022] In the motor 1, a plurality of (two in this embodiment) bearings 61 and 62 are provided to rotatably support the shaft 2 relative to the housing 5. One of the bearings 61 and 62 is provided at the bottom 51a of the housing body 51. A protrusion 51aa (hereinafter referred to as a bearing housing) and a hole 51ab are provided at the bottom 51a of the housing body 51 that supports the bearing 61 along the length direction of the shaft 2, and the bearing 61 is fixed to the bearing housing 51aa by pressing or the like. The other bearing 62 is fixed to the protrusion 52aa (hereinafter referred to as a bearing housing) of the cover body 52 by pressing or the like. In the radial direction, the outer diameter and inner diameter of one bearing 61 are approximately the same as the outer diameter and inner diameter of the other bearing 62, respectively. It should be noted that the outer diameter and inner diameter of one bearing 61 are approximately the same as the outer diameter and inner diameter of the other bearing 62, and the outer diameter or inner diameter or both of the other bearing 62 may be set larger than the outer diameter or inner diameter or both of the one bearing 61. In addition, the hole portion 51ab may not be provided in the bottom portion 51a.

[0023] The shaft 2 has two ends 2a and 2b, one end 2b located on the housing body 51 side is rotatably supported relative to the housing body 51 via a bearing 61, and the other end 2a located on the cover body 52 side is rotatably supported via another bearing 62. Thus, the shaft 2 is rotatably fixed to the housing body 51 via the bearing 61, and is rotatably fixed to the cover body 52 via the bearing 62, and the other end 2a of the shaft 2 protrudes from the cover body 52. ​​The rotational force can be transmitted to the outside from the other end 2a of the shaft 2. The shaft 2 is fixed to the rotor 3, and when the rotor 3 rotates due to the electromagnetic action of the stator 4 and the rotor 3, the shaft 2 rotates together with the rotor 3.

[0024] The stator 4 is composed of a stator core 41 including teeth 43 , and a coil 42 . The stator core 41 is composed of a laminate of magnetic materials such as silicon steel plates, and is composed of an annular portion (hereinafter referred to as an annular portion) 44 arranged coaxially with the shaft 2, and a plurality of magnetic pole portions (hereinafter referred to as teeth portions) 43 formed to extend from the annular portion 44 toward the shaft 2 side. The coil 42 is wound around each of the plurality of teeth 43. The stator core 41 and the coil 42 are insulated from each other by an insulating layer 45 formed of an insulator.

[0025] Next, the rotor 3 of this embodiment will be described in detail. Figure 3 2 is a partially enlarged cross-sectional view of the rotor 3 according to the present embodiment. The rotor core 33, which is one of the components of the rotor 3, is formed of a laminate of a plurality of magnetic bodies, and has a hole 34 into which the shaft 2 is inserted; an annular portion 33a having a hole 34 provided in the center; a plurality of pole pieces 33b formed radially toward the stator 4 with a position separated from the outer surface 33ad of the annular portion 33a as a base point D; and a pair of connecting portions 33c, 33c connecting the end of each pole piece 33b on the base point D side of the plurality of pole pieces 33b to the outer surface 33ad of the annular portion 33a. The plurality of pole pieces 33b radially extend from the annular portion 33a via a pair of connecting portions 33c, 33c toward the outside (stator 4) in the radial direction. In addition, the annular portion 33a has an outer surface 33ad and an inner surface 33ae forming the hole 34.

[0026] The plurality of pole pieces 33b are respectively provided with an outer surface 33bc, an inner surface 33bd located on the side of the annular portion 33a, two side surfaces 33be circumferentially opposed to the side surface (31e) of the first magnet described later, and a plurality of protrusions 33f, and a gap 33g is formed between the protrusions 33f and the first magnet in the radial direction. The protrusions 33f extend toward other adjacent pole pieces 33b in the circumferential direction. In addition, in the circumferential direction, among two adjacent pole pieces 33b, the protrusions 33f of one pole piece 33b and the protrusions 33f of the other pole piece 33b are separated in a manner that they are opposed to each other and form a given gap.

[0027] A plurality of first magnets 31 are disposed between the circumferentially adjacent magnetic pole pieces 33b, 33b. These plurality of first magnets 31 extend radially from the annular portion 33a in the radial direction. In the first magnet 31, two surfaces intersecting the circumferential direction are magnetic pole surfaces 31n, 31s, and these magnetic pole surfaces 31n, 31s are in contact with the side surface 33be of the magnetic pole piece 33b.

[0028] In addition, the first magnet 31 has an outer surface 31c radially opposite to the protrusion 33f of the pole piece 33b, an inner surface 31a radially located on the side of the annular portion 33a, and two side surfaces 31e circumferentially opposite to the pole piece 33b, and the pole surfaces 31n and 31s correspond to the two side surfaces 31e.

[0029] In addition, a plurality of second magnets 32 are arranged between a pair of connecting portions 33c, 33c. The second magnet 32 ​​includes an inner surface 32g located on the annular portion 33a side, an outer surface 32h located on the pole piece 33b side, and two side surfaces 32i, 32i located on the pair of connecting portions 33c, 33c side. In addition, in the second magnet 32, the inner surface 32g and the outer surface 32h intersecting (orthogonal) with the radial direction of the rotor 3 become magnetic pole surfaces 32n, 32s, and any one of these magnetic pole surfaces 32n, 32s becomes the outer surface 32h, and is in contact with the end (inner surface 33bd) on the annular portion 33a side of the magnetic pole piece 33b.

[0030] Figure 3 Among the multiple pole pieces 33b, the description will focus on two pole pieces marked with numbers 33bn and 33bs. In the circumferential direction, among the two side surfaces 33be and 33be possessed by a pole piece (33bn or 33bs), the pole of the first magnet 31 located on one side surface, the pole of the first magnet 31 located on the other side surface, and the pole of the second magnet 32 ​​located on the inner surface 33bd side of the pole piece (33bn or 33bs) in the radial direction are the same poles.

[0031] Specifically, in the pole piece 33bn, two pole faces 31n, 31n of the first magnet 31 contacted by two circumferential side faces 33be, 33be and a pole face 32n of the second magnet 32 ​​contacted by the radial inner face 33bd all form N poles. On the other hand, in the pole piece 33bs, the two pole faces 31s, 31s of the first magnet 31 contacted by the two circumferential side faces 33be, 33be and the pole face 32s of the second magnet 32 ​​contacted by the radial inner face 33bd all form S poles.

[0032] That is, in a certain pole piece 33b, the magnets are arranged so that the two pole faces 31n, 31n or 31s, 31s contacted by the first magnet 31 on the two circumferential side faces 33be, 33be, and the pole face 32n or 32s contacted by the second magnet 32 ​​all become the same poles.

[0033] The magnetic force of the N pole or S pole is applied to the magnetic pole piece 33b, and is released radially outward as one magnetic flux line. The magnetic pole of the magnetic pole piece 33b is configured so that the N pole and the S pole are alternately repeated in the circumferential direction. For example, in the pole piece 33bn, the magnetic flux lines coming out from the two pole surfaces 31n of the first magnet 31 which is long in the radial direction of the rotor 3 are bundled, and are released from the radial inner side toward the outer side, from the end (outer surface 33bc) of the pole piece 33bn on the opposite side of the base point D side (annular portion 33a side), and act on the stator 4.

[0034] At this time, in the area of ​​the magnetic pole surface 31n that is away from the outer surface 33bc of the rotor 3 (close to the departure point D, the inner surface 33bd), for example, Figure 3 In the region X in the rotor 33bn (hereinafter simply referred to as "region X"), since the distance from the region X to the outer surface 33bc is long, it is difficult for the magnetic flux to be directed toward the outer surface 33bc. However, in the present embodiment, the second magnet 32, which is the same N-pole as the magnetic pole face 31n and faces the radially outer direction, is arranged at the end (inner surface 33bd) on the base point D side of the magnetic pole piece 33bn, so the magnetic flux from the region X is effectively directed toward the outer surface 33bc together with the magnetic flux from the magnetic pole face 32n. Therefore, the magnetic flux generated by the first magnet 31, which is long in the radial direction of the rotor 3, can be effectively utilized. The magnetic flux generated from the first magnet 31 is effectively directed toward the outer surface 33bc together with the magnetic flux generated from the second magnet 32, not only in the pole piece 33bn but also in all the pole pieces 33b including the pole piece 33bs.

[0035] exist Figure 4 2 shows a schematic diagram simulating how the magnetic flux from the magnet 131 draws magnetic lines of force in the rotor core in a conventional rotor (see Patent Document 2) that does not have the second magnet 32. Figure 4 It can be seen that only in the area of ​​about two-thirds of the long side direction of the magnet 131 that is long in the radial direction of the rotor, the magnetic lines of force are directed in the radial outward direction of the pole piece 133b, and the magnetic lines of force from the remaining one-third of the area leak from the connecting portion 133c serving as the magnetic circuit to the annular portion 133a.

[0036] exist Figure 5 2 shows a schematic diagram simulating how the magnetic flux from the magnets (31, 32) draws magnetic lines of force in the rotor core in this embodiment. Figure 5 It can be seen that, despite the use of the first magnet 31 which is long in the radial direction of the rotor 3, the magnetic lines of force from most of the area in the long side direction are directed to the radially outer side of the magnetic pole piece 33b. Therefore, the following situation is shown: the number of magnetic lines of force leaking from the connecting portion 33c as a magnetic circuit to the annular portion 33a is equal to Figure 4 The rotor shown is extremely small compared to the conventional rotor without the second magnet 32 ​​, and the magnetic flux can be effectively utilized.

[0037] As described above, according to the present embodiment, since the magnetic flux generated by the magnets (magnets 31 and 32) can be effectively utilized, the amount of magnets used can be reduced, and cost reduction, lightness, and miniaturization of the motor 1 can be achieved. According to the research of the present inventors, the following is confirmed: Compared with the prior art (refer to Figure 4 ) compared to the conventional motor 1, even if the amount of magnets used (volume basis) is reduced by about 20%, the performance of the motor 1 is no different.

[0038] Will Figure 4 and Figure 5 By comparison, it can be seen that in this embodiment, compared with the prior art, the length of the magnetic pole piece 33b in the radial direction is shorter, and the length of the first magnet 31 in the radial direction is also shorter. Even if the second magnet 32 ​​is also included in the calculation, the amount of magnets used (volume basis) is about 20% less. Figure 4 In the case of the conventional technology shown and the case of the present embodiment, the density of the magnetic flux emitted from the outer peripheral side of the pole piece 33b is approximately the same. Alternatively, according to the present embodiment, it is also possible to provide a motor having higher efficiency and performance than the conventional technology without reducing the amount of magnets used or reducing the amount of magnets used very much.

[0039] The connecting portion 33c and its surroundings ( Figure 3 A partial enlarged view of the area C) in FIG. Figure 6 In addition, Figure 6 In the figure, for convenience, the three connecting parts 33c are labeled 33c-1, 33c-2, and 33c-3 in a clockwise manner.

[0040] like Figure 6 As shown, a pair of connecting parts 33c are connected to both ends of the end of the annular part 33a side of the pole piece 33b in the circumferential direction. A pair of connecting parts 33c-2 and 33c-3 extend radially from the annular part 33a toward two adjacent pole pieces 33b, and the distance (circumferential direction) between the pair of connecting parts 33c-2 and 33c-3 on the pole piece 33b side is greater than the distance (circumferential direction) between the pair of connecting parts 33c-2 and 33c-3 on the annular part 33a side. In other words, the distance between the pair of connecting parts 33c-1 and 33c-2 from the annular part 33a toward one pole piece 33b becomes narrower, and the distance (circumferential direction) between the pair of connecting parts 33c-1 and 33c-2 on the pole piece 33b side is smaller than the distance (circumferential direction) between the pair of connecting parts 33c-1 and 33c-2 on the annular part 33a side.

[0041] In addition, the width of each of the pair of radially connecting portions 33c is formed to be smaller than the width of any one of the pole piece 33b, the first magnet 31, and the second magnet 32. In this way, by forming the pair of connecting portions 33c, a non-contact surface with respect to the first magnet 31 and the second magnet 32 ​​is provided, so that the (surface) area of ​​the non-contact region is increased, or the magnetic flux passing through the pair of connecting portions 33c is saturated, thereby improving the magnetic efficiency of the rotor 3.

[0042] In addition, if Figure 6 As shown, a first gap 35 is formed between the inner surface 31a, which is the end of the annular portion 33a in the first magnet 31, and the outer surface 33ad of the annular portion 33a (region C surrounded by the inner surface 31a and the connecting portions 33c-2 and 33c-3). By providing the first gap 35 in the region C near the first magnet 31, a so-called magnetic isolation portion is formed, so that the short circuit of the magnetic flux can be suppressed inside the rotor core 33. In addition, by providing the first gap 35 in the region C, the connecting portions 33c-2 and 33c-3 as the magnetic path are thinned, and the leakage of the magnetic flux can be suppressed.

[0043] The width of the first gap 35 in the circumferential direction is formed so as to increase from the annular portion 33a toward the magnetic pole piece 33b. By setting such a shape, the strength of the connecting portion 33c can be improved.

[0044] The side surfaces 32i, 32i of the second magnet 32 ​​are separated in a manner to form a given gap 32j relative to a pair of connecting portions 33c in the circumferential direction. Thus, in the circumferential direction, second gaps 36a, 36b are formed in regions D1, D2 between the two side portions 32a, 32b and the pair of connecting portions 33c-1, 33c-2 in the second magnet 32, respectively. By providing the second gaps 36a, 36b in regions D1, D2, short-circuiting of the magnetic flux of the second magnet 32 ​​can be suppressed. In addition, by providing the second gaps 36a, 36b in regions D1, D2, the connecting portions 33c-1, 33c-2 as the magnetic circuit become thinner, and leakage of the magnetic flux can be suppressed.

[0045] The width of the second gaps 36a and 36b in the circumferential direction is formed so as to become narrower as it moves from the annular portion 33a toward the magnetic pole piece 33b. By setting such a shape, the strength of the connecting portion 33c can be improved.

[0046] The two corners 32c and 32d on the side of the pole piece 33b of the second magnet 32 ​​are in contact with the two corners (hereinafter referred to as connection points) 37a and 37b facing the second gaps 36a and 36b where the pair of connecting parts 33c-1 and 33c-2 and the pole piece 33b are connected. In this way, the end (inner surface 33bd) on the side of the annular portion 33a (base point D side) of the pole piece 33b is in contact with the second magnet 32 ​​with a sufficient width, so that the magnetic flux from the pole surface 32n of the second magnet 32 ​​can be efficiently injected into the pole piece 33b, and the leakage of the magnetic flux can be suppressed.

[0047] The two corners (hereinafter referred to as connection points) 38a and 38b facing the second gaps 36a and 36b where the pair of connecting parts 33c-1 and 33c-2 and the annular part 33a are connected are separated from the two corners 32e and 32f on the annular part 33a side of the second magnet 32. In this way, the short circuit of the magnetic flux of the second magnet 32 ​​can be suppressed. In addition, in this way, the connecting parts 33c-1 and 33c-2 as the magnetic circuit are thinned, which can suppress the leakage of the magnetic flux.

[0048] The inner surface 32g of the second magnet 32, which is opposite to the outer surface 32h in contact with the pole piece 33b, contacts the outer surface 33ad of the annular portion 33a. The second magnet 32 ​​contacts both the pole piece 33b and the annular portion 33a in the rotor core 33 in the radial direction and is sandwiched therebetween, thereby strengthening the connection through the connection portion 33c and improving the strength of the rotor core 3.

[0049] As described above, the motor 1 using the rotor 3 of the embodiment can be used as a driving device for a mobile body such as an electric car, a compressor of an air conditioner (air conditioner) and other electronic devices used in the home, and a rotation driving device of various other electronic devices. In particular, it can be preferably used in applications requiring high output, high torque, energy saving, space saving, etc.

[0050] The rotor of the present invention and the motor and electronic device using the rotor are described above by listing preferred embodiments, but the rotor of the present invention and the motor and electronic device using the rotor are not limited to the configuration of the above embodiments. For example, the shape of the connecting portion 33c in the above embodiment can be changed to other shapes.

[0051] (First Modification) Figure 7 FIG. 1 is a partially enlarged cross-sectional view of a rotor 73 according to a first modified example of the present invention. Figure 7 In the embodiment, the same components as those in the above embodiment are also given Figure 3 The same reference numerals are used to designate the components, and detailed descriptions of their functions, structures, etc. are omitted. The rotor 73 of the present modification is different from the rotor 3 of the above-described embodiment in the shape of the connection portion ( 73c , 33c ).

[0052] like Figure 7 As shown, the connection portion 73c in this modification is a shape in which the width of the connection portion 73c in the circumferential direction narrows as it moves away from the annular portion 33a. Specifically, in the radial direction, between the first magnet 31 and the annular portion 33a, the connection portions 73cc divided into two in the pair of connection portions 73c intersect at the intersection 73ca, and one connection portion 73cb extends from the intersection 73ca toward the annular portion 33a and is connected to the outer surface 33ad of the annular portion 33a. The intersection 73ca is located between the inner surface 31d of the first magnet 31 and the outer surface 33ad of the annular portion 33a in the radial direction. The aforementioned first gap 35 is formed between the pair of connection portions 73c and at a position on the first magnet 31 side relative to the intersection 73ca. In addition, in the circumferential direction, second gaps 36a, 36b are formed between the intersection 73ca and the second magnet 32.

[0053] Furthermore, the configuration of this example in which the two connected portions 73cc intersect at the intersection portion 73ca to form one connected portion 73cb is also included in the concept of "a pair of connected portions (73c)" referred to in the present invention. The connection portion 73c functioning as a magnetic path preferably has a narrow magnetic flux path in order to suppress leakage of magnetic flux from the first magnet 31 and the second magnet 32. In a narrow magnetic flux path, the magnetic flux is easily saturated and no more magnetic flux leaks out.

[0054] Therefore, as long as there is a narrow part at any position of the magnetic circuit, the leakage of magnetic flux can be suppressed. In the case of the connecting portion (73c, 33c), if there is a narrow part of the magnetic circuit at a certain position from the annular portion 33a side to the magnetic pole piece 33b side, it can be said that the leakage suppression effect of magnetic flux is manifested.

[0055] However, the connection portion 73c of this modification is preferably used because the magnetic path is narrowed as close as possible to the magnetic pole piece 33b, thereby further improving the effect of suppressing the leakage of magnetic flux. In addition, by not narrowing the entire connection portion (73c, 33c) and widening the other widths, the connection strength can be increased, thereby improving the strength of the rotor 73.

[0056] (Second Modification) The shape of the connection portion is not limited to the above-described embodiment or the above-described modified examples. exist Figure 8 FIG. 1 is a partially enlarged cross-sectional view of a rotor 73 according to a second modified example of the present invention. Figure 8 Similarly, for components that have the same functions as those in the above-mentioned embodiments, the same Figure 3 The same reference numerals are used to designate the components, and detailed descriptions of their functions, structures, etc. are omitted.

[0057] like Figure 8 As shown, the pair of connecting portions 83c, 83c in this modified example are parallel to the surface intersecting (orthogonal) with the circumferential direction of the second magnet 32, and the circumferential width is uniform. In addition, the two corners 32c, 32d on the side of the magnetic pole piece 33b of the second magnet 32 ​​do not contact the pair of connecting portions 83c, 83c and the two connecting points 87a, 87b of the magnetic pole piece 33b facing the second gaps 86a, 86b.

[0058] Therefore, although it is not possible to expect the unique functions and effects of the connecting portion (73c, 33c) of the characteristic shape as shown in the above-mentioned embodiment and the first modified example, even the structure of this modified example will fully exert the excellent functions and effects of the present invention such as being able to effectively utilize the magnetic flux generated from the magnets (31, 32). In addition, since the shape is not complicated, the manufacturing adaptability is excellent.

[0059] (Third Modification) exist Fig. 9 A partially enlarged cross-sectional view of a rotor 93 according to a third modified example of the present invention is shown in FIG. Fig. 9 Similarly, for components that have the same functions as those in the above-mentioned embodiments, the same Figure 3 The same reference numerals are used to designate the components, and detailed descriptions of their functions, structures, etc. are omitted. In this modification, the outer shape of the second magnet 92 is different from the second magnet 32 ​​of the above embodiment, and the shape of the corresponding rotor 93 is also different from the rotor 3 of the above embodiment.

[0060] In this modification, the second magnet 92 is seamlessly fitted into the area surrounded by the outer surface 33ad of the annular portion 33a of the rotor 93, the inner surface 93d of the pole piece 93b, and the pair of connecting portions 33c, and is surrounded by and in contact with them. That is, the second gaps 36a and 36b in the above embodiment are not provided.

[0061] The outer surface 92h of the second magnet 92, which the pole piece 93b contacts, contacts the inner surface 93d of the pole piece 93b. The outer surface 92h of the second magnet 92 and the inner surface 93d of the pole piece 93b are curved convexly toward the hole 34 of the rotor 93. By curving the outer surface 92h of the second magnet 92 and the inner surface 93d of the pole piece 93b in this way, it is possible to suppress the leakage of magnetic flux to the connecting portion 33c.

[0062] The maximum value θ1 of the angle formed between the tangent line L1 on the curved outer surface 92h of the second magnet 92 and the side surface 31e of the first magnet 31 is larger than that of the angle formed by the tangent line L1 on the curved outer surface 92h of the second magnet 92 and the side surface 31e of the first magnet 31 in the above embodiment. Figure 3 ) and the extended line of the inner surface 31n of the first magnet 31 are larger. Therefore, the leakage of magnetic flux to the connecting portion 33c can be suppressed. On the other hand, regardless of whether the leakage of magnetic flux to the connecting portion 33c can be reduced, the contact area between the outer surface 92h of the second magnet 92 on the side of the magnetic pole piece 93b and the inner surface 93d of the magnetic pole piece 93b becomes larger, so the strength and rigidity of the rotor 93 as a whole can be improved.

[0063] When examining the maximum value θ1 of the angle, the target angle may be the angle formed by the tangent line L1 on the curved outer surface 92 h of the second magnet 92 and the extension line of the side surface 31 e of the first magnet 31 .

[0064] (Fourth Modification) Fig.10 A partial enlarged cross-sectional view of the rotor 103 according to the fourth modified example of the present invention is shown. Fig.10 A partial enlarged view of area E) in FIG. Fig.11 In addition, Fig.10 as well as Fig.11 Similarly, for components that have the same functions as those in the above-mentioned embodiments, the same Figure 3 The same reference numerals are used to indicate the functions and structures thereof, and detailed descriptions thereof are omitted. In this modification, similarly to the third modification, the outer shape of the second magnet 102 is different from the second magnet 32 ​​of the above embodiment, and the shape of the corresponding rotor 103 is also different from the rotor 3 of the above embodiment.

[0065] In this modification, the second magnet 102 is, like the third modification, seamlessly fitted into the region surrounded by the outer surface 103ad of the annular portion 103a of the rotor 103, the inner surface 33d of the pole piece 33b, and the pair of connecting portions 33c, and is surrounded by and in contact with them. That is, the second gaps 36a and 36b in the above embodiment are not provided.

[0066] The inner surface 102g of the second magnet 102 on the side opposite to the outer surface 102h in contact with the pole piece 33b contacts the outer surface 103ad of the annular portion 103a. The inner surface 102g of the second magnet 102 and the outer surface 103ad of the annular portion 103a are curved convexly toward the outside of the rotor 103. By curving the inner surface 102g of the second magnet 102 and the outer surface 103ad of the annular portion 103a in this way, it is possible to suppress leakage of magnetic flux to the connecting portion 33c.

[0067] In addition, if Fig.11 As shown, the minimum value θ2 of the angle formed by the tangent line L2 in the curved inner surface 102g of the second magnet 102 and the extension line L3 of the connecting portion 33c (the center line) is smaller than that of the straight line passing through the inner surface 32g (see Figure 3 ) and the extended line of the connecting portion 33c are smaller. Therefore, it is possible to suppress the leakage of magnetic flux to the connecting portion 33c. On the other hand, regardless of whether the leakage of magnetic flux to the connecting portion 33c can be reduced, the contact area between the inner surface 92g of the second magnet 102 on the annular portion 103a side and the outer surface 103ad in the annular portion 103a becomes larger, thereby improving the overall strength and rigidity of the rotor 103.

[0068] In addition, it is also possible to have a configuration that combines the features of both the third variant and the fourth variant. That is, it can be in the following shape: Fig. 9 As shown, the outer surface 92h of the second magnet 92 and the inner surface 93d of the pole piece 93b are convexly curved toward the hole portion 34 of the rotor 93, and as shown in FIG. Fig.10 As shown, the inner surface 102 g of the second magnet 102 and the outer surface 103 ad of the annular portion 103 a are convexly curved toward the outside of the rotor 103 .

[0069] In addition, those skilled in the art can appropriately modify the rotor of the present invention and the motor and electronic device using the rotor according to the prior art knowledge. Even if modified, as long as they have the structure of the present invention, they are of course included in the scope of the present invention. Description of symbols

[0070] 1 motor; 2 shaft; 2a, 2b end; 3 rotor; 31 first magnet; 31a inner surface; 31c outer surface; 31e side surface; 31n, 31s magnetic pole surface; 32 second magnet; 32n, 32s magnetic pole surface; 32a, 32b both sides; 32c, 32d, 32e, 32f corner; 32g inner surface; 32h outer surface; 32i side surface; 32j gap; 33 rotor core; 33 a annular portion; 33ad outer surface; 33ae inner surface; 33b pole piece; 33bc outer surface; 33bd inner surface; 33be side surface; 33f protrusion; 33c connecting portion; 33g gap; 34 hole portion; 35 first gap; 36a, 36b second gap; 4 stator; 41 stator core; 42 coil; 43 tooth portion; 44 annular portion; 45 insulating layer; 5 housing; 51 housing body; 51a bottom; 51aa bearing housing (protruding portion); 51b cylinder; 51c outer peripheral portion; 52 cover; 52a flat plate; 52aa bearing housing (protruding portion); 52c outer peripheral portion; 73 rotor; 73c connecting portion (a pair of connecting portions); 73ca intersection; 73cb connecting portion (one connecting portion); 73cc connecting portion (two connecting portions); 83 rotor; 83c connecting portion; 8 6a, 86b second gap; 87a, 87b connection point; 92 second magnet; 92h outer surface; 93 rotor; 93b pole piece; 93d inner surface; 102 second magnet; 102g inner surface; 103 rotor; 103a annular portion; 103ad outer surface; 131 magnet; 133a annular portion; 133b pole piece; 133c connection portion; C region; D base point; E region; X region.

Claims

1. A rotor comprising: a rotor core having an annular portion and a plurality of magnetic pole pieces radially extending from the annular portion via a pair of connecting portions; a plurality of first magnets disposed between the magnetic pole pieces adjacent to each other in the circumferential direction; a plurality of second magnets disposed between the pair of connecting portions, In the circumferential direction, each of the first magnets contacts the side surfaces of two adjacent pole pieces. In the radial direction, the second magnet contacts the inner surface of the pole piece.

2. The rotor according to claim 1, wherein: The pole of the first magnet located on one of the two side surfaces of the pole piece in the circumferential direction, the pole of the first magnet located on the other side surface, and the pole of the second magnet located on the inner surface side of the pole piece in the radial direction are the same poles.

3. The rotor according to claim 1 or 2, wherein: The pair of connection portions are connected to both ends of the end portion of the pole piece on the annular portion side in the circumferential direction.

4. The rotor according to claim 1, wherein: In the radial direction, a first gap is provided between the inner surface of the first magnet and the outer surface of the annular portion.

5. The rotor according to claim 4, wherein: The width of the first gap in the circumferential direction increases from the annular portion toward the pole piece.

6. The rotor according to claim 1, wherein: In the circumferential direction, a second gap is provided between both side surfaces of the second magnet and the side surfaces of the pair of connection portions.

7. The rotor according to claim 6, wherein: The width of the second gap in the circumferential direction becomes narrower from the annular portion toward the pole piece.

8. The rotor according to claim 6 or 7, wherein: The corner of the second magnet contacts a corner on the magnetic pole piece side among the plurality of corners of the second gap.

9. The rotor according to claim 8, wherein: Among the plurality of corners included in the second gap, a corner on the annular portion side is separated from a corner of the second magnet.

10. The rotor according to claim 1, wherein: In the radial direction, the inner surface of the second magnet contacts the outer surface of the annular portion.

11. The rotor according to claim 1, wherein: In a radial direction, an outer surface of the second magnet and an inner surface of the pole piece are bent toward an outer side of the rotor.

12. The rotor according to claim 1, wherein: In the radial direction, the inner surface of the second magnet and the outer surface of the annular portion are curved toward the hole portion of the annular portion.

13. The rotor according to claim 1, wherein: The width of the connection portion in the circumferential direction becomes narrower from the annular portion toward the magnetic pole piece.

14. A motor comprising: The rotor according to claim 1; a shaft fixed to the rotor; The stator includes a coil and a magnetic body around which the coil is wound.

15. An electronic device comprising the motor according to claim 14.

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