Magnetic Gear Device

Abstract

To provide a magnetic gear device that can improve manufacturability and assemblability, and restrain an increase of an axial length.SOLUTION: An outside rotor 18 of a magnetic gear device comprises fitting concave parts 44 in first side surfaces 40a of pole pieces 40, and comprises fitting convex parts 46 fitted into the fitting concave parts 44, in second side surfaces 42a of pole piece holding members 42. The outside rotor 18 comprises a first end part constituting member 36 connected to one end part of each of a plurality of the pole piece holding members 42, and a second end part constituting member 38 connected to the other end part of each of the plurality of the pole piece holding members 42. One end part of each of a plurality of the pole pieces 40 is in contact with the first end part constituting member 36. The other end part of each of the plurality of the pole pieces 40 is in contact with the second end part constituting member 38.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a magnetic gear device having an inner rotor and an outer rotor. [Background technology]

[0002] The magnetic gear device of Patent Document 1 comprises a rotor for high-speed rotation housed inside a housing and a stator arranged on the inner periphery of the housing. Multiple permanent magnets are arranged on the outer periphery of the rotor. Multiple permanent magnets are arranged on the inner periphery of the stator. A magnetic modulation section is provided between the rotor and the stator. The magnetic modulation section comprises a magnetic body made of a magnetic material and a non-magnetic body made of a non-magnetic material. The magnetic body and non-magnetic body are fixed to each other in the circumferential direction of the magnetic modulation section. A protrusion on the axial end of each non-magnetic body is fitted into a recess in an end component that is integral with the output shaft. The magnetic modulation section and the output shaft are connected via the end component. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5350438 Summary of the Invention [Problem to be solved by the invention]

[0004] The magnetic gear device of Patent Document 1 has a pair of protrusions arranged at the end of the non-magnetic body in the extension direction, and the end of the magnetic body is arranged and held between the pair of protrusions, and the protrusions of adjacent non-magnetic bodies are connected to each other, thereby increasing the fixing strength between the non-magnetic body and the magnetic body.

[0005] However, providing the protrusions reduces the manufacturability of the non-magnetic body and complicates the assembly of the non-magnetic body and the magnetic body. Furthermore, since the end of the magnetic body is held by the protrusions, the axial length of the non-magnetic body with the protrusions increases.

[0006] The present invention aims to solve the above-mentioned problems. [Means for solving the problem]

[0007] One aspect of the present invention is a magnetic gear device comprising: an inner rotor having rotor-side magnets; an outer rotor formed in a cylindrical shape surrounding the inner rotor and rotating at a slower speed than the inner rotor as the inner rotor rotates; a cylindrical stator core; and a stator having stator-side magnets arranged on the inner periphery of the stator core and surrounding the outer rotor; wherein the outer rotor comprises a plurality of magnetic pole pieces made of a magnetic material and a plurality of magnetic pole piece holding members made of a non-magnetic and non-conductive member; and the plurality of magnetic pole pieces and the plurality of magnetic pole piece holding members are arranged alternately in the circumferential direction of the outer rotor, and wherein the plurality of magnetic pole pieces and the plurality of magnetic pole piece holding members are arranged alternately in the circumferential direction of the outer rotor, and A mating recess extending along the axial direction of the outer rotor is provided on one of the opposing side surfaces of the holding member, and a mating protrusion extending along the axial direction and fitting into the mating recess is provided on the other of the opposing side surfaces. The outer rotor has a disk-shaped first end component connected to one ends of the plurality of pole piece holding members and a disk-shaped second end component connected to the other ends of the plurality of pole piece holding members, the first end component being formed from a non-magnetic and non-conductive material, and one ends of the plurality of pole pieces abutting against the first end component, and the second end component being formed from a non-magnetic and non-conductive material, and the other ends of the plurality of pole pieces abutting against the second end component. [Effects of the Invention]

[0008] According to the present invention, in the outer rotor, the circumferentially adjacent pole pieces and pole piece holding members are fitted together using fitting recesses and fitting protrusions, thereby ensuring the strength of the outer rotor made up of the pole pieces and pole piece holding members against centrifugal force. This simplifies the configuration of the outer rotor and improves the manufacturability of the outer rotor compared to a structure in which a magnetic body is held between a pair of non-magnetic protrusions. By fitting the fitting recesses and fitting protrusions, the outer rotor can be easily assembled. This improves the assembly efficiency of the outer rotor. Because one end and the other end of the pole pieces abut against the first and second end component members, respectively, the axial length of the pole piece holding member is reduced. As a result, the axial length of the outer rotor is reduced, enabling it to be made smaller. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is an overall cross-sectional view of a magnetic gear device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 3 is an external perspective view showing the outer rotor of the magnetic gear device of FIG. [Figure 4] FIG. 4 is an enlarged cross-sectional view of the magnetic gear device shown in FIG. [Figure 5] FIG. 5 is an enlarged cross-sectional perspective view showing a portion of the pole pieces and pole piece holding members of the outer rotor. [Figure 6] FIG. 6 is an external perspective view showing a state in which the pole piece holding member is assembled to the second end component member. [Figure 7] FIG. 7 is an exploded perspective view of the outer rotor shown in FIG. [Figure 8] FIG. 8 is an axial cross-sectional view of the outer rotor. DETAILED DESCRIPTION OF THE INVENTION

[0010] As shown in FIG. 1, the magnetic gear device 10 according to this embodiment includes an annular housing 12, a stator 14, an inner rotor 16, an outer rotor 18 that rotates at a slower speed than the inner rotor 16, and an output shaft 20 connected to the outer rotor 18.

[0011] The stator 14 is accommodated inside the housing 12. The stator 14 includes a cylindrical stator core 22 and a plurality of slots (not shown). Coils are arranged in the slots. The stator core 22 is formed by stacking a plurality of steel plates 22a in the axial direction. A plurality of stator side magnets 26 are arranged on the inner peripheral surface of the stator core 22. Each stator side magnet 26 is a permanent magnet. The plurality of stator side magnets 26 are arranged along the inner peripheral surface of the stator core 22 (see FIG. 2). The north poles and south poles of each stator side magnet 26 are arranged alternately along the circumferential direction of the stator core 22. Each stator side magnet 26 faces the outer peripheral surface of the outer rotor 18.

[0012] As shown in FIG. 2, the inner rotor 16 is rotatably disposed inside the stator 14. The inner rotor 16 includes a first rotor body 28 and a plurality of rotor-side magnets 30. The first rotor body 28 is cylindrically formed from a magnetic material. A rotating shaft 32 is connected to the center of the first rotor body 28. As shown in FIG. 1, the rotating shaft 32 includes a rotor holding portion 32a that holds the first rotor body 28, a tip portion 32b provided at the tip of the rotor holding portion 32a, and an intermediate portion 32c provided on the base end side of the rotor holding portion 32a. The tip portion 32b and the intermediate portion 32c each have a smaller diameter than the rotor holding portion 32a. The rotor-side magnets 30 are disposed on the outer periphery of the first rotor body 28. The plurality of rotor-side magnets 30 are disposed circumferentially along the outer circumferential surface of the first rotor body 28. The plurality of rotor-side magnets 30 are disposed with north and south poles alternating along the circumferential direction of the inner rotor 16. Each rotor-side magnet 30 faces the inner circumferential surface of the outer rotor 18 .

[0013] The outer rotor 18 surrounds the inner rotor 16. The outer rotor 18 is rotatably disposed between the stator 14 and the inner rotor 16.

[0014] As shown in Fig. 1, the outer rotor 18 has a cylindrical second rotor body 34, a first end component 36, and a second end component 38. As shown in Fig. 3, the second rotor body 34 includes a plurality of pole pieces 40 and a plurality of pole piece holding members 42. Below, a description will be given of a case where 19 pole pieces 40 and 19 pole piece holding members 42 are included. Note that the numbers of pole pieces 40 and pole piece holding members 42 are not limited to this.

[0015] As shown in FIG. 2, the multiple pole pieces 40 are formed of a magnetic material and have the same shape. The multiple pole pieces 40 are arranged along the circumferential direction of the second rotor body 34. Each pole piece 40 is a segment obtained by equally dividing the second rotor body 34 along the circumferential direction of the second rotor body 34. The multiple pole pieces 40 are equally spaced from one another with pole piece holding members 42 between them. In other words, the multiple pole pieces 40 are arranged radially around the central axis of the outer rotor 18 (second rotor body 34). When viewed axially of the outer rotor 18 shown in FIG. 2, each pole piece 40 has an arc-shaped cross section. Each pole piece 40 is a long member extending in the axial direction of the outer rotor 18 (see FIG. 3).

[0016] 4, each pole piece 40 has a pair of first side surfaces 40a and a pair of fitting recesses 44. The first side surfaces 40a are respectively located at one end and the other end of each pole piece 40 in the circumferential direction. The first side surfaces 40a are flat surfaces extending along the axial direction of the second rotor body 34. The first side surfaces 40a face the two adjacent pole piece holding members 42, respectively.

[0017] The pair of fitting recesses 44 are arranged on the pair of first side surfaces 40a. Each fitting recess 44 is a recess recessed into the first side surface 40a (see FIG. 5). In the radial direction of the second rotor body 34, the fitting recesses 44 are arranged in the center of the first side surface 40a. In the radial direction of the second rotor body 34, the positions of each fitting recess 44 on each first side surface 40a are the same.

[0018] The fitting recess 44 is recessed from the first side surface 40a in the circumferential direction of the second rotor body 34. When viewed in the axial direction of the second rotor body 34, the fitting recess 44 has a semicircular cross section. As shown in Figure 6, the fitting recess 44 extends along the axial direction of the outer rotor 18. The fitting recess 44 penetrates from one end to the other end of the pole piece 40 in the extension direction.

[0019] As shown in FIG. 4, the multiple pole piece holding members 42 are formed in the same shape from a non-magnetic, non-conductive material. The pole piece holding members 42 are molded articles made of resin. The multiple pole piece holding members 42 are arranged along the circumferential direction of the second rotor body 34. Each pole piece holding member 42 is a segment obtained by equally dividing the second rotor body 34 along the circumferential direction of the second rotor body 34 (see FIG. 3). The multiple pole piece holding members 42 are equally spaced from one another, with the pole pieces 40 between them. In other words, the multiple pole piece holding members 42 are arranged radially around the central axis of the outer rotor 18 (second rotor body 34). When viewed axially of the outer rotor 18 shown in FIG. 4, each pole piece holding member 42 has an arc-shaped cross section. Each pole piece holding member 42 is an elongated member extending in the axial direction of the outer rotor 18 (see FIG. 3).

[0020] A plurality of pole pieces 40 and a plurality of pole piece holding members 42 are arranged alternately in the circumferential direction of outer rotor 18 .

[0021] Each pole piece holding member 42 has a pair of second side surfaces 42a, a pair of mating protrusions 46, a first connecting portion 48a, and a third connecting portion 48b (see FIG. 7). The second side surfaces 42a are respectively disposed at one end and the other end of each pole piece holding member 42 in the circumferential direction. The second side surfaces 42a are flat surfaces extending along the axial direction of the second rotor body 34. The second side surfaces 42a face the first side surfaces 40a of the adjacent pole pieces 40. The second side surfaces 42a of the pole piece holding member 42 and the first side surfaces 40a of the pole pieces 40 are capable of contacting each other.

[0022] The pair of mating protrusions 46 are arranged on the pair of second side surfaces 42a. Each mating protrusion 46 is a protrusion that protrudes from the second side surface 42a. In the radial direction of the second rotor body 34, the mating protrusions 46 are arranged in the center of the second side surface 42a. In the radial direction of the second rotor body 34, the positions of each mating protrusion 46 on each second side surface 42a are the same.

[0023] The fitting protrusion 46 protrudes from the second side surface 42a in the circumferential direction of the second rotor body 34. When viewed from the axial direction of the second rotor body 34, the cross-sectional shape of the fitting protrusion 46 is semicircular. The cross-sectional shape of the fitting protrusion 46 corresponds to the cross-sectional shape of the fitting recess 44.

[0024] The fitting protrusions 46 extend along the axial direction of the outer rotor 18 (see FIG. 6). The fitting protrusions 46 penetrate the pole piece holding member 42 from one end to the other in the extension direction. Each fitting protrusion 46 fits into the fitting recess 44 of the pole piece 40 adjacent in the circumferential direction of the outer rotor 18. At this time, the second side surface 42a of the pole piece holding member 42 and the first side surface 40a of the pole piece 40 abut against each other.

[0025] With the plurality of pole pieces 40 and the plurality of pole piece holding members 42 arranged alternately in the circumferential direction, the fitting recesses 44 and the fitting protrusions 46 are fitted together to form the outer rotor 18, in which the plurality of pole pieces 40 and the plurality of pole piece holding members 42 are connected in an annular shape. The pole piece holding member 42 has a columnar holding body portion 43 arranged between the first end component member 36 and the second end component member 38. A pair of second side surfaces 42a and a pair of fitting protrusions 46 are provided on the holding body portion 43. One end face of the holding body portion 43 abuts against the first end component member 36, and the other end face of the holding body portion 43 abuts against the second end component member 38. In the axial direction of the outer rotor 18, the length of the holding body portion 43 is approximately the same as the length of the pole pieces 40. Therefore, one end face of the holding body 43 and one end face of the pole piece 40 are flush with each other, and the other end face of the holding body 43 and the other end face of the pole piece 40 are flush with each other.

[0026] As shown in FIG. 8, the first connection portion 48a is disposed at one axial end of the pole piece holding member 42. The first connection portion 48a is a convex portion that protrudes in the axial direction from one end face of the pole piece holding member 42. The third connection portion 48b is disposed at the other axial end of the pole piece holding member 42. The third connection portion 48b is a convex portion that protrudes in the axial direction from the other end face of the pole piece holding member 42. The first connection portion 48a and the third connection portion 48b have the same shape. When viewed in the axial direction of the second rotor body 34, the first and third connection portions 48a, 48b are circular. However, the first and third connection portions 48a, 48b are not limited to being circular.

[0027] As shown in FIG. 1 , the first end component 36 is connected to one end of the plurality of pole piece holding members 42. The first end component 36 is formed from a non-magnetic and non-conductive material. The first end component 36 is a molded product made of a resin material. The first end component 36 is disposed at one axial end of the second rotor body 34. The first end component 36 has a disk-shaped first cover portion 50, a shaft hole 52 disposed in the center of the first cover portion 50, and a first bearing support portion 53.

[0028] One ends of the plurality of pole piece holding members 42 are connected to the first cover portion 50. One ends of the plurality of pole pieces 40 abut against the first cover portion 50 (see FIG. 3). The first bearing support portion 53 is formed in an annular shape and protrudes from the first cover portion 50 toward the first rotor body 28. The first bearing support portion 53 is disposed radially outward of the shaft hole 52. A first shaft bearing 55 is held inside the first bearing support portion 53. The first shaft bearing 55 rotatably supports the middle portion 32c of the rotating shaft 32.

[0029] The second end component member 38 is connected to the other ends of the multiple pole piece holding members 42. The second end component member 38 is formed from a non-magnetic and non-conductive material. The second end component member 38 is a molded product made of a resin material. The second end component member 38 is disposed at the other axial end of the second rotor body 34. The second end component member 38 has a disk-shaped second cover portion 54 and a second bearing support portion 56. The first cover portion 50 covers one axial end of the second rotor body 34. The second cover portion 54 covers the other axial end of the second rotor body 34.

[0030] The other ends of the plurality of pole piece holding members 42 are connected to the second cover portion 54. The other ends of the plurality of pole pieces 40 abut against the second cover portion 54 (see FIG. 3). The output shaft 20 is integrally formed at the center of the second cover portion 54. The second bearing support portion 56 is formed in an annular shape and protrudes from the second cover portion 54 toward the first rotor body 28. A second shaft bearing 57 is held inside the second bearing support portion 56. The second shaft bearing 57 rotatably supports the tip end 32b of the rotating shaft 32. In other words, the rotating shaft 32 is rotatably supported by the first shaft bearing 55 and the second shaft bearing 57.

[0031] The outer diameters of the first and second cover portions 50, 54 and the outer diameter of the second rotor body 34 are approximately the same (see FIG. 3).

[0032] As shown in FIG. 7, the outer edge of the first cover part 50 has second connection parts 58a. The second connection parts 58a can be connected to the first connection parts 48a of the pole piece holding members 42 that constitute the second rotor body 34. The second connection parts 58a have a plurality of holes 60a. The plurality of holes 60a are arranged at equal intervals along the circumferential direction of the first cover part 50. As shown in FIG. 8, the plurality of holes 60a and the plurality of first connection parts 48a of the second rotor body 34 face each other in the axial direction of the outer rotor 18. The diameter of the holes 60a is such that the first connection parts 48a can be fitted into them. The holes 60a have a circular shape that can fit into the first connection parts 48a.

[0033] The shape of the hole 60a is not limited to a circle as long as it corresponds to the shape of the first connecting portion 48a. The second connecting portion 58a is not limited to a concave shape formed by the hole 60a, and the first connecting portion 48a connected to the second connecting portion 58a is convex. The second connecting portion 58a may be convex, and the first connecting portion 48a connected to the second connecting portion 58a may be concave.

[0034] As shown in FIG. 7, the outer edge of the second cover portion 54 has a fourth connection portion 58b. The fourth connection portion 58b can be connected to the third connection portion 48b of the pole piece holding member 42 that constitutes the second rotor body 34. The fourth connection portion 58b has a plurality of holes 60b. The plurality of holes 60b are arranged at equal intervals along the circumferential direction of the second cover portion 54. As shown in FIG. 8, the plurality of holes 60b and the plurality of third connection portions 48b of the second rotor body 34 face each other in the axial direction of the outer rotor 18. The diameter of the hole 60b is a diameter that allows the third connection portion 48b to fit into. The hole 60b has a circular shape that allows the third connection portion 48b to fit into.

[0035] The shape of the hole 60b is not limited to a circular shape as long as it corresponds to the shape of the third connection portion 48b. The fourth connection portion 58b is not limited to a concave shape formed by the hole 60b, and the third connection portion 48b connected to the fourth connection portion 58b is convex. The fourth connection portion 58b may be convex, and the third connection portion 48b connected to the fourth connection portion 58b may be concave.

[0036] As shown in Fig. 8, shaft hole 52 opens at the center of first cover part 50. Shaft hole 52 passes through first cover part 50 in the axial direction. As shown in Fig. 1, rotating shaft 32 of inner rotor 16 is inserted through shaft hole 52. Rotating shaft 32 protrudes through shaft hole 52 to the outside of first end component member 36. First cover part 50 is rotatably supported with respect to housing 12 by bearing 62a.

[0037] 8, output shaft 20 protrudes axially away from second cover portion 54 of second end component 38. This allows outer rotor 18 and output shaft 20 to rotate integrally. Second cover portion 54 is rotatably supported relative to housing 12 by bearing 62b.

[0038] The first end component 36 is disposed at one axial end of the second rotor body 34, and the first connection portions 48a of each pole piece holding member 42 are fitted into the respective hole portions 60a of the second connection portion 58a. As a result, one axial end of the second rotor body 34 is covered by the first end component 36. The second end component 38 is disposed at the other axial end of the second rotor body 34, and the third connection portions 48b of each pole piece holding member 42 are fitted into the respective hole portions 60b of the fourth connection portion 58b. As a result, the other axial end of the second rotor body 34 is covered by the second end component 38.

[0039] Next, the assembly of the outer rotor 18 of the magnetic gear device 10 will be described.

[0040] First, the multiple pole piece holding members 42 are assembled to the second end component 38. As shown in FIG. 6, the third connection portion 48b of each pole piece holding member 42 is press-fitted into the hole 60b of the fourth connection portion 58b of the second end component 38. The third connection portion 48b and the fourth connection portion 58b may be joined to each other with an adhesive. This fixes the multiple pole piece holding members 42 to the outer edge portion of the second end component 38. This connects and fixes the multiple pole piece holding members 42 to the outer edge portion of the second end component 38 (second cover portion 54).

[0041] The pole piece holding members 42 are equally spaced apart in the circumferential direction of the second end component member 38. Each pole piece holding member 42 is perpendicular to the second cover portion 54 of the second end component member 38. The second side surfaces 42a of two adjacent pole piece holding members 42 face each other. The outer surface of each pole piece holding member 42 forms part of the outer peripheral surface of the second rotor body 34. The inner surface of each pole piece holding member 42 forms part of the inner peripheral surface of the second rotor body 34.

[0042] Next, the second rotor body 34 is formed by inserting each pole piece 40 into the space between two adjacent pole piece holding members 42. Each pole piece 40 is inserted into the space between two adjacent pole piece holding members 42 along the axial direction of the second rotor body 34. Between the two pole piece holding members 42, the first side surface 40a of each pole piece 40 faces and abuts against the second side surface 42a of the pole piece holding member 42. The mating protrusions 46 of the two adjacent pole piece holding members 42 are mated with the mating recesses 44 of each pole piece 40. The outer surface of each pole piece 40 forms part of the outer peripheral surface of the second rotor body 34. The inner surface of each pole piece 40 forms part of the inner peripheral surface of the second rotor body 34. As shown in FIG. 3 , multiple pole pieces 40 are abutted against and held by the outer edge of the first end component 36.

[0043] At this time, adhesive is applied between the first side surface 40a including the fitting recess 44 and the second side surface 42a including the fitting protrusion 46. The first side surface 40a and the second side surface 42a are firmly connected to each other by the adhesive. The fitting recess 44 and the fitting protrusion 46 are firmly connected to each other by the adhesive.

[0044] In this way, the pole pieces 40 and the pole piece holding members 42 are arranged alternately in the circumferential direction with respect to the second end component member 38, and are fitted to one another via the fitting recesses 44 and the fitting protrusions 46. In other words, the second rotor body 34 is formed by connecting a plurality of pole pieces 40 and pole piece holding members 42 in the circumferential direction, and the other axial end of the second rotor body 34 is connected to the second end component member 38. The other axial end of the second rotor body 34 is covered by the second end component member 38. Each pole piece 40 is connected to the second end component member 38 by two adjacent pole piece holding members 42.

[0045] Finally, the second end component 38 having the output shaft 20 is assembled to the second rotor body 34 .

[0046] First, the inner rotor 16 is housed inside the second rotor body 34 from one axial end of the second rotor body 34. As shown in FIG. 3, one axial end of the second rotor body 34 is covered with the first end component 36. The first connection portions 48a of the second rotor body 34 are press-fitted into the holes 60a of the second connection portion 58a of the first end component 36. At this time, the first connection portions 48a and the second connection portions 58a are joined to each other with an adhesive. As a result, the multiple pole piece holding members 42 are connected and fixed to the outer edge portion of the first end component 36 (first cover portion 50). The multiple pole pieces 40 are held in contact with the outer edge portion of the first end component 36. As shown in FIG. 3, the first end component 36 is fixed to one axial end of the second rotor body 34, completing the assembly of the outer rotor 18. The inner rotor 16 is housed inside the outer rotor 18.

[0047] The method of assembling the outer rotor 18 is not limited to the above-described method. After the second rotor body 34 is formed by alternately fastening the plurality of pole pieces 40 and the plurality of pole piece holding members 42, the first and second end components 36, 38 may be fastened to one end and the other end of the second rotor body 34 in the axial direction, respectively.

[0048] Next, the operation of the magnetic gear device 10 will be described.

[0049] When power is supplied to the coils of the stator 14 from a power source (not shown), a magnetic flux is generated by the current flowing through the coils. The magnetic flux, the rotor-side magnets 30 of the inner rotor 16, and the magnetic flux create a magnetic force that causes the inner rotor 16 to rotate around the rotating shaft 32. The magnetic flux generated by the rotation of the inner rotor 16 causes the outer rotor 18, which has an output shaft 20, to rotate at a reduced speed at a predetermined reduction ratio. The rotational speed of the outer rotor 18 is slower than that of the inner rotor 16. The rotational force of the outer rotor 18 is output as a driving force from the output shaft 20 to the outside. In other words, by rotating the inner rotor 16, the magnetic gear device 10 can rotate the outer rotor 18 at a slower speed than the inner rotor 16 in accordance with the reduction ratio.

[0050] When the outer rotor 18 rotates, centrifugal force acts radially outward on the second rotor body 34. The pole pieces 40 and pole piece holding members 42 are firmly connected in the circumferential direction by the mating recesses 44 and mating protrusions 46. Therefore, the outer rotor 18 has sufficient strength to withstand the centrifugal force.

[0051] As described above, in the embodiment of the present invention, in the outer rotor 18 having a plurality of pole pieces 40 and pole piece holding members 42, circumferentially adjacent pole pieces 40 and pole piece holding members 42 are fitted together using the fitting recesses 44 and fitting protrusions 46. Therefore, when the outer rotor 18 rotates, the outer rotor 18 (second rotor body 34) made up of the pole pieces 40 and the pole piece holding members 42 can be ensured to have sufficient strength against centrifugal force. This simplifies the configuration of the outer rotor 18 and improves manufacturability. By fitting the fitting recesses 44 and fitting protrusions 46 together, the outer rotor 18 can be easily assembled. This improves the assembly of the outer rotor 18.

[0052] One axial end of the pole piece 40 abuts against the first end component 36, and the other axial end of the pole piece 40 abuts against the second end component 38, so the axial length of the pole piece holding member 42 is reduced compared to a configuration in which the end of a magnetic material is held by a non-magnetic protrusion. This reduces the axial length of the outer rotor 18, making it possible to make it smaller.

[0053] By making the multiple pole piece holding members 42, the first end component member 36 and the second end component member 38 into molded products made of resin material, the pole piece holding members 42, the first end component member 36 and the second end component member 38 made of non-magnetic and non-conductive material can be easily formed.

[0054] By joining the mating recesses 44 and mating protrusions 46 with an adhesive, each pole piece 40 and each pole piece holding member 42 can be connected more firmly in the circumferential direction.

[0055] The first connection portions 48a of the multiple pole piece holding members 42 are connected to the second connection portions 58a of the first end component member 36, and the third connection portions 48b of the multiple pole piece holding members 42 are connected to the fourth connection portions 58b of the second end component member 38. As a result, when the outer rotor 18 rotates, the first and second connection portions 48a, 58a, which are perpendicular to the direction in which centrifugal force acts, can reliably maintain the connected state between the first end component member 36 and each pole piece holding member 42, and the connected state between the second end component member 38 and each pole piece holding member 42.

[0056] By joining the first connecting portion 48a and the second connecting portion 58a with adhesive, and joining the third connecting portion 48b and the fourth connecting portion 58b with adhesive, the connection strength between each pole piece holding member 42 and the first end component member 36, and the connection strength between each pole piece holding member 42 and the second end component member 38 can be further increased.

[0057] The above embodiment can be summarized as follows.

[0058] The above embodiment includes an inner rotor (16) having rotor-side magnets (30); an outer rotor (18) formed in a cylindrical shape surrounding the inner rotor, which rotates at a slower speed than the inner rotor as the inner rotor rotates; a stator (14) having a cylindrical stator core (22) and a stator-side magnet (26) arranged on the inner periphery of the stator core, the stator (14) surrounding the outer rotor; and The magnetic gear device (10) is configured such that the outer rotor includes a plurality of magnetic pole pieces (40) made of a magnetic material and a plurality of magnetic pole piece holders (42) made of a non-magnetic and non-conductive material, and the plurality of magnetic pole pieces and the plurality of magnetic pole piece holders are alternately arranged in the circumferential direction of the outer rotor, In the plurality of pole pieces and the plurality of pole piece holding members, a fitting recess (44) extending along the axial direction of the outer rotor is provided on one of the mutually facing side surfaces (40 a, 42 a) of the pole pieces and pole piece holding members adjacent to each other in the circumferential direction, and a fitting protrusion (46) extending along the axial direction and fitting into the fitting recess is provided on the other of the mutually facing side surfaces, The outer rotor has a first end component (36) in the form of a disk connected to one end of the plurality of pole piece holding members, and a second end component (38) in the form of a disk connected to the other end of the plurality of pole piece holding members, the first end component is formed from a non-magnetic and non-conductive material, one ends of the plurality of magnetic pole pieces abut against the first end component; The second end component is formed from a non-magnetic and non-conductive material, and the other ends of the plurality of magnetic pole pieces abut against the second end component.

[0059] Each of the plurality of magnetic pole piece holding members, the first end portion component member, and the second end portion component member is a molded product made of a resin material.

[0060] The fitting recess and the fitting protrusion are joined with an adhesive.

[0061] One end of each of the plurality of magnetic pole piece holding members has a first connecting portion (48a) formed in a convex or concave shape in the axial direction, the first end component member has a second connection portion (58a) formed in a concave or convex shape in the axial direction and to which the first connection portion is connected, The other end of each of the plurality of magnetic pole piece holding members has a third connection portion (48b) formed in a convex or concave shape in the axial direction, The second end component member has a fourth connecting portion (58b) formed in a concave or convex shape in the axial direction and to which the third connecting portion is connected.

[0062] The first connecting portion and the second connecting portion are joined by an adhesive, and the third connecting portion and the fourth connecting portion are joined by an adhesive.

[0063] The present invention is not limited to the above disclosure, and various configurations can be adopted without departing from the gist of the present invention. [Explanation of symbols]

[0064] 10...magnetic gear device 14...stator 16...Inner rotor 18...Outer rotor 20...Output shaft 26...Stator side magnet 30... rotor side magnet 34... second rotor body 36...First end portion component 38...Second end portion component 40...Magnetic pole piece 40a...First side 42...Magnetic pole piece holding member 42a...Second side surface 44...Mating recess 46...Mating protrusion

Claims

1. an inner rotor having rotor-side magnets; an outer rotor formed in a cylindrical shape surrounding the inner rotor, which rotates at a slower speed than the inner rotor as the inner rotor rotates; a stator having a cylindrical stator core and a stator side magnet disposed on the inner periphery of the stator core, the stator surrounding the outer rotor; and A magnetic gear device in which the outer rotor comprises a plurality of magnetic pole pieces made of a magnetic material and a plurality of magnetic pole piece holding members made of a non-magnetic and non-conductive material, the plurality of magnetic pole pieces and the plurality of magnetic pole piece holding members being alternately arranged in the circumferential direction of the outer rotor, In the plurality of pole pieces and the plurality of pole piece holding members, a fitting recess extending along the axial direction of the outer rotor is provided on one of the mutually facing side surfaces of the pole pieces and pole piece holding members adjacent to each other in the circumferential direction, and a fitting protrusion extending along the axial direction and fitting into the fitting recess is provided on the other of the mutually facing side surfaces, The outer rotor is a first end component member having a disk shape, the first end component member being made of a non-magnetic and non-conductive material and connected to one end of the plurality of pole piece holding members; a second end component member having a disk shape, the second end component member being made of a non-magnetic and non-conductive material and connected to the other end of the plurality of pole piece holding members; and Each of the plurality of magnetic pole piece holding members has a main body portion extending in the axial direction and having a first end face and a second end face at both ends in the axial direction, a first convex portion protruding in the axial direction from the first end face of the main body portion, and a second convex portion protruding in the axial direction from the second end face of the main body portion, the first end component member has a first abutment surface provided at an end in the axial direction and abutting against the first end surface, and a first hole portion that opens in the first abutment surface and into which the first protrusion is inserted, the second end component member has a second abutment surface provided at an end in the axial direction and abutting against the second end surface, and a second hole portion that opens in the second abutment surface and into which the second protrusion is inserted, the first abutment surface of the first end component member abuts against one ends of the plurality of pole pieces and the first end faces of the plurality of pole piece holding members, and the second abutment surface of the second end component member abuts against the other ends of the plurality of pole pieces and the second end faces of the plurality of pole piece holding members.

2. 2. The magnetic gear device according to claim 1, The magnetic gear device, wherein each of the plurality of magnetic pole piece holding members, the first end component member, and the second end component member is a molded product made of a resin material.

3. 3. The magnetic gear device according to claim 2, The magnetic gear device wherein the mating recess and the mating protrusion are joined with an adhesive.

4. 4. The magnetic gear device according to claim 3, the first protrusion and the first hole are joined with an adhesive, and the second protrusion and the second hole are joined with an adhesive.

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