JP2013047546A - Magnetic gear device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic gear device that includes a plurality of magnetic tooth parts formed independently of each other and can prevent deformation of the plurality of magnetic tooth parts through which magnetic flux of a magnet piece passes.SOLUTION: The magnetic gear device includes an outer gear, an inner gear and a stator gear 7 disposed between the outer gear and the inner gear. The stator gear 7 includes: a body part 41 including the plurality of magnetic tooth parts 53 arranged concentrically with a cylindrical hole of the outer gear while spaced apart from each other and a plurality of fixed parts 50 provided between the plurality of magnetic tooth parts 53; and a base part 47 connected to the body part 41.

Description

  The present invention relates to a magnetic gear device that transmits power using magnetic attraction or repulsion.

  The gear is a mechanical element that transmits power such as torque. In general gears, power is transmitted by contact between a driving-side tooth and a driven-side tooth, so that friction occurs between the driving-side tooth and the driven-side tooth. Therefore, a lubricant is required between the driving-side teeth and the driven-side teeth. In addition, noise due to contact between the tooth on the driving side and the tooth on the driven side is also generated. Thus, in recent years, magnetic gears without tooth contact have been developed. Since the magnetic gear transmits torque without contact, it does not require a lubricant and can be driven without noise.

  On the other hand, a speed reduction mechanism used in a robot, a copying machine, or the like is required to have a torque limiter function that cuts off torque (cuts off power transmission) when excessive torque is applied. Since the magnetic gear has a torque limiter function, it is possible to configure a speed reduction mechanism having a torque limiter function with a simple structure.

  An example of the magnetic gear device is described in Non-Patent Document 1. The magnetic gear device described in Non-Patent Document 1 has a cylindrical high-speed rotor and a low-speed rotor, and the outer peripheral surface of the high-speed rotor faces the inner peripheral surface of the low-speed rotor. . The power of the high-speed rotor is transmitted to the low-speed rotor by using the magnetic attraction generated between the magnet piece attached to the outer peripheral surface of the high-speed rotor and the magnet piece attached to the inner peripheral surface of the low-speed rotor. .

  In addition, a plurality of iron pieces (magnetic tooth portions) for passing the magnetic flux of the magnet pieces are arranged between the magnet pieces attached to the outer peripheral surface of the high speed rotor and the magnet pieces attached to the inner peripheral surface of the low speed rotor. Yes.

K. Atallah and D.C. Howe, “A Novel High-Performance Magnetic Gear”, IEEE Transactions on Magnetics, JULY 2001, Vol. 37. No. 4, p. 2844-2846

  However, in the magnetic gear device described in Non-Patent Document 1, however, in the magnetic gear device described in Non-Patent Document 1, since eddy currents are generated, a plurality of iron pieces (magnetic tooth portions) are in an independent state. Needed to be formed. Further, when a plurality of iron pieces (magnetic tooth portions) are formed in an independent state, there is a problem that when the high speed rotor and the low speed rotor are rotated, the iron pieces are deformed by the action of electromagnetic force.

  This invention is made | formed in view of such a prior art, forms a some iron piece (magnetic tooth part) in an independent state, respectively, and is a plurality of iron pieces (magnetic tooth part) which lets the magnetic flux of a magnet piece pass. It is an object of the present invention to provide a magnetic gear device that can prevent deformation.

In order to solve the above problems and achieve the object of the present invention, a magnetic gear device of the present invention comprises an external gear, an internal gear, and a stator gear disposed between the external gear and the internal gear. Yes.
The external gear includes a cylindrical outer cylinder having a cylinder hole and a plurality of outer magnet pieces attached to the inner periphery of the outer cylinder.
The internal gear is disposed in a cylindrical hole of the external gear, and includes a cylindrical inner cylinder and a plurality of inner magnet pieces attached to the outer peripheral portion of the inner cylinder.
The stator gear includes a main body having a plurality of magnetic teeth arranged concentrically with a cylindrical hole of the external gear, and a plurality of fixing portions provided between the plurality of magnetic teeth, and And a base portion to be connected.

  According to the magnetic gear device of the present invention, since the plurality of fixing portions are interposed between the plurality of magnetic tooth portions arranged concentrically with the cylindrical hole of the external gear, the rigidity of the plurality of magnetic tooth portions is increased. Increases and the plurality of magnetic tooth portions become independent from each other. As a result, it is possible to prevent the magnetic flux from passing in the circumferential direction and to prevent the deformation of the plurality of magnetic tooth portions through which the magnetic flux of the magnet piece passes.

It is sectional drawing which shows the magnetic gear apparatus concerning the embodiment of this invention. It is sectional drawing which follows the AA line shown in FIG. It is a disassembled perspective view of the external gear of the magnetic gear apparatus concerning the embodiment of this invention. 4A is a cross-sectional view of the external gear of the magnetic gear device according to the embodiment of the present invention, and FIG. 4B is a cross-sectional view taken along line BB shown in FIG. 4A. 1 is a perspective view of a stator gear of a magnetic gear device according to an embodiment of the present invention. 6A is a cross-sectional view of the stator gear of the magnetic gear device according to the embodiment of the present invention, and FIG. 6B is a cross-sectional view taken along the line CC shown in FIG. 6A. 7A is a plan view of a stator member of a stator gear according to an embodiment of the present invention, and FIG. 7B is a side view showing a state in which the stator members of the stator gear according to an embodiment of the present invention are stacked. . FIG. 7C is a side view showing a state in which the fixing portion is interposed in the stator member in the stator gear according to the embodiment of the present invention, and FIG. 7D is a stator gear in the magnetic gear device according to the embodiment of the present invention. It is a top view of the main-body part. It is explanatory drawing of the state in which the 1st magnetic flux converging part of the external gear opposed the magnetic tooth part of the stator gear in the magnetic gear apparatus concerning the embodiment of this invention. It is explanatory drawing of the state which the 2nd magnetic flux converging part of the external gear opposed to the magnetic tooth part of the stator gear in the magnetic gear apparatus concerning the embodiment of this invention. It is explanatory drawing of the state which the 3rd magnetic flux converging part of the external gear opposed to the magnetic tooth part of the stator gear in the magnetic gear apparatus concerning the embodiment of this invention. It is explanatory drawing of the state which the 4th magnetic flux converging part of the external gear opposed to the magnetic tooth part of the stator gear in the magnetic gear apparatus concerning the embodiment of this invention. It is explanatory drawing of the state which the 1st magnetic flux converging part of the external gear in the magnetic gear apparatus concerning the embodiment of this invention opposes the magnetic tooth part adjacent to the magnetic tooth part shown in FIG. It is explanatory drawing which shows the arrangement | sequence of the magnet piece of the magnetic gear apparatus concerning embodiment of this invention, and distribution of magnetic flux density. FIG. 13A is an explanatory view showing the arrangement of magnetic pieces and magnetic flux density distribution of the internal gear, and FIG. 13B is an explanatory view showing the arrangement of magnetic pieces and magnetic flux density distribution of the external gear.

  Embodiments of the magnetic gear device according to the present invention will be described below with reference to FIGS. In addition, the same code | symbol is attached | subjected to the common member in each figure. The present invention is not limited to the following form.

1. Configuration of Magnetic Gear Device First, a magnetic gear device according to an embodiment of the present invention (hereinafter referred to as “this example”) will be described with reference to FIG.
FIG. 1 is a cross-sectional view showing a configuration of a magnetic gear device according to this example.

  As shown in FIG. 1, the magnetic gear device 1 of the present invention includes a case 2, a first rotating shaft 3, a second rotating shaft 4, an external gear 5, an internal gear 6, and a stator gear 7. I have. The external gear 5 is fixed to the second rotary shaft 4, and the internal gear 6 is fixed to the first rotary shaft 3. The stator gear 7 is fixed to the case 2.

  Case 2 is a housing formed of a nonmagnetic material. Examples of the material of the case 2 include metals such as austenitic stainless steel, aluminum, and copper, or synthetic resins.

  The case 2 has a hollow portion 2a and an opening 2b. In the hollow portion 2a of the case 2, an external gear 5, an internal gear 6, and a stator gear 7 are arranged. In the opening 2b of the case 2, a part of the external gear 5 and the stator gear 7 disposed in the hollow portion 2a are exposed.

  The case 2 includes a bottom plate 11, a first support plate 12, a second support plate 13, and a reinforcing piece 14. The bottom plate 11 is disposed to face the opening 2b. The first support plate 12 and the second support plate 13 are continuous with the bottom plate 11 and protrude substantially vertically. The first support plate 12 faces the second support plate 13. The second support plate 13 is provided with a bearing 17, and a reinforcing piece 14 is fixed to the outer surface of the second support plate 13. The reinforcing piece 14 includes a bearing 18.

  The first rotating shaft 3 is made of a nonmagnetic material. Examples of the material of the first rotating shaft 3 include the same materials as the material of the case 2.

  The first rotating shaft 3 passes through the first support plate 12 and a base portion 47 described later of the stator gear 7. The base portion 47 is provided with a bearing 16. The first rotating shaft 3 is rotatably attached to the base portion 47 of the stator gear 7 via a bearing 16 provided on the base portion 47.

  The second rotating shaft 4 is made of a nonmagnetic material, like the first rotating shaft 3. Examples of the material of the second rotating shaft 4 include the same materials as those of the case 2.

  The 2nd rotating shaft 4 is comprised from the axial part 4a and the disc part 4b. The shaft portion 4 a passes through the second support plate 13 and the reinforcing piece 14. The shaft portion 4 a is attached to the second support plate 13 via a bearing 17 and is rotatably attached to the reinforcing piece 14 via a bearing 18.

  The disc part 4b of the second rotating shaft 4 is provided at the tip of the shaft part 4a. Moreover, the bearing 19 is provided in the surface on the opposite side to the axial part 4a in the disc part 4b. A tip end portion of the first rotating shaft 3 is rotatably attached to the disc portion 4b via a bearing 19. Further, the axis of the first rotating shaft 3 and the axis of the second rotating shaft 4 coincide with each other.

  The bearings 16, 17, 18 and 19 are rolling bearings (ball bearings) having rolling elements 16a, 17a, 18a and 19a, respectively. The rolling elements 16a to 19a of the bearings 16 to 19 are preferably formed of a nonmagnetic material or a material having a high carbon content. Usually used rolling bearings have a high carbon content because they are quenched to ensure hardness. Therefore, you may use such a normal rolling bearing.

  In addition, the bearing which concerns on this invention is not limited to a rolling bearing, For example, a slide bearing, a fluid bearing, etc. can also be applied.

[Internal gear]
Next, a specific example of the internal gear 6 will be described with reference to FIG.
2 is a cross-sectional view taken along line AA of the magnetic gear device according to the present example shown in FIG.
As shown in FIG. 2, the internal gear 6 includes an inner cylinder 31 and a plurality of inner magnet pieces 32A and 32B. And the internal gear 6 is arrange | positioned in the external gear 5 (refer FIG. 1).

  The inner cylinder 31 is formed in a cylindrical shape having a circular cylinder hole 31a. The first rotating shaft 3 is fitted in the cylindrical hole 31a. The inner cylinder 31 is made of a magnetic material. Examples of the material of the inner cylinder 31 include iron and a silicon steel plate.

  The inner cylinder 31 may be formed by laminating a plurality of plate members such as iron and silicon steel plates. When the inner cylinder 31 is formed by laminating a plurality of plate-like members, the inner cylinder 31 is fixed and integrally formed by a fixing method such as caulking, welding, or adhesive.

  When the internal gear 6 rotates, an eddy current flows in the axial direction of the inner cylinder 31. However, when the inner cylinder 31 is formed by laminating a plurality of plate-like members, a minute gap generated when the plurality of plate-like members are laminated becomes resistance, and eddy current can be interrupted. Therefore, torque loss due to eddy current can be suppressed. In order to more reliably block the eddy current, a current insulating material or a current insulating coating film may be interposed between the overlapping plate members.

  A plurality of inner magnet pieces 32 </ b> A and 32 </ b> B are attached to the outer peripheral portion of the inner cylinder 31. The plurality of inner magnet pieces 32 </ b> A and 32 </ b> B are plate-like permanent magnets that are long in the axial direction of the inner cylinder 31. The plurality of inner magnet pieces 32 </ b> A and 32 </ b> B are magnetized in the radial direction of the inner cylinder 31.

  The inner magnet piece 32A has an N pole on the radially outer side of the inner cylinder 31 (external gear 5 side), and an S pole on the radially inner side of the inner cylinder 31 (first rotation shaft 3 side). On the other hand, in the inner magnet piece 32B, the radially outer side (external gear 5 side) of the inner cylinder 31 is an S pole, and the radially inner side (first rotation shaft 3 side) of the inner cylinder 31 is an N pole. .

  The plurality of inner magnet pieces 32 </ b> A and 32 </ b> B are alternately arranged in the circumferential direction of the inner cylinder 31. Therefore, the plurality of inner magnet pieces 32 </ b> A and 32 </ b> B are arranged such that different magnetic poles are adjacent to each other in the circumferential direction of the tube hole 31 a of the inner tube 31.

  In this example, by sticking the plurality of inner magnet pieces 32A and 32B to the inner cylinder 31 made of a magnetic material, the magnetic moment of the inner cylinder 31 can be aligned and a large surface magnetic flux density can be obtained. Further, since the plurality of inner magnet pieces 32A and 32B can be attracted to the outer periphery of the inner cylinder 31 by magnetic attraction, the plurality of inner magnet pieces 32A and 32B can be easily attached to the outer periphery of the inner cylinder 31. it can.

[External gear]
Next, a specific example of the external gear 5 will be described with reference to FIGS. 3 and 4.
FIG. 3 is an exploded perspective view of the external gear of the magnetic gear device according to the present example. 4A is a cross-sectional view of the external gear of the magnetic gear device according to this example, and FIG. 4B is a cross-sectional view taken along the line BB shown in FIG. 4A.

  As shown in FIG. 3, the external gear 5 includes an outer cylinder 21, a plurality of first outer magnet pieces 22A and 22B, and a plurality of second outer magnet pieces 23A and 23B.

  The outer cylinder 21 is formed in a cylindrical shape having a circular cylinder hole 21a. As shown in FIGS. 3 and 4A, the outer cylinder 21 has a protrusion 21b that protrudes radially inward from the cylinder hole 21a. The disc portion 4b of the second rotating shaft 4 is inserted from one side in the axial direction of the outer cylinder 21, and the disc portion 4b is fitted into the cylinder hole 21a. And the protrusion part 21b of the outer side cylinder 21 is contact | abutted to the disc part 4b of the 2nd rotating shaft 4 (refer FIG. 4A). The outer cylinder 21 is made of a magnetic material. In addition, as a material of the outer side cylinder 21, although iron, a silicon steel plate, etc. are mentioned, a laminated iron core is preferable, for example.

  When the outer cylinder 21 is formed using the laminated iron core, a minute gap between the overlapping plate-like members becomes a resistance, and the eddy current flowing in the axial direction of the outer cylinder 21 can be blocked. In order to more reliably block the eddy current, a current insulating material or a current insulating coating film may be interposed between the overlapping plate members.

  As shown in FIG. 4B, a plurality of first outer magnet pieces 22A and 22B are arranged in the circumferential direction of the cylinder hole 21a in the cylinder hole 21a of the outer cylinder 21. A plurality of second outer magnet pieces 23A, 23B are arranged on the inner periphery of the plurality of first outer magnet pieces 22A, 22B. That is, the second outer magnet pieces 23A and 23B are disposed on the inner side in the radial direction of the outer cylinder 21 than the first outer magnet pieces 22A and 22B.

  The plurality of first outer magnet pieces 22A and 22B are elongated and substantially rod-shaped permanent magnets respectively along the axial direction of the outer cylinder 21 (see FIG. 3). The plurality of first outer magnet pieces 22 </ b> A and 22 </ b> B are magnetized in the radial direction of the outer cylinder 21.

  In the first outer magnet piece 22A, the outer side in the radial direction of the outer cylinder 21 is an N pole, and the inner side in the radial direction of the outer cylinder 21 is an S pole. On the other hand, in the first outer magnet piece 22B, the outer side in the radial direction of the outer cylinder 21 is the S pole, and the inner side in the radial direction of the outer cylinder 21 is the N pole. Different magnetic poles of the first outer magnet pieces 22 </ b> A and the first outer magnet pieces 22 </ b> B are alternately arranged in the circumferential direction of the outer cylinder 21.

  The plurality of second outer magnet pieces 23 </ b> A and 23 </ b> B are elongate and substantially rod-shaped permanent magnets along the axial direction of the outer cylinder 21 (see FIG. 3). The plurality of second outer magnet pieces 23 </ b> A and 23 </ b> B are magnetized in the circumferential direction of the outer cylinder 21.

  In the second outer magnet piece 23A, one side in the circumferential direction of the outer cylinder 21 is an N pole, and the other side in the circumferential direction of the outer cylinder 21 is an S pole. On the other hand, in the second outer magnet piece 23B, one side in the circumferential direction of the outer cylinder 21 is an S pole, and the other side in the circumferential direction of the outer cylinder 21 is an N pole. The plurality of second outer magnet pieces 23 </ b> A and 23 </ b> B are arranged so that the same magnetic poles are adjacent to each other in the circumferential direction of the outer cylinder 21.

  Further, the N poles of the second outer magnet pieces 23A and 23B are arranged on the N pole of the first outer magnet piece 22B. At this time, the N poles of the second outer magnet pieces 23 </ b> A and 23 </ b> B and the N pole of the first outer magnet piece 22 </ b> B are adjacent to each other in the radial direction of the outer cylinder 21. The boundary where the N poles of the second outer magnet pieces 23 </ b> A and 23 </ b> B are adjacent to each other is located in the middle portion of the first outer magnet piece 22 </ b> B in the circumferential direction of the outer cylinder 21.

  The S poles of the second outer magnet pieces 23A and 23B are disposed on the S pole of the first outer magnet piece 22A. At this time, the south poles of the second outer magnet pieces 23A and 23B and the south pole of the first outer magnet piece 22A are adjacent to each other in the radial direction of the outer cylinder 21. The boundary where the S poles of the second outer magnet pieces 23 </ b> A and 23 </ b> B are adjacent to each other is located at an intermediate portion of the first outer magnet piece 22 </ b> A in the circumferential direction of the outer cylinder 21.

  The second outer magnet pieces 23 </ b> A and 23 </ b> B have notches at both ends in the circumferential direction of the outer cylinder 21. Since the second outer magnet pieces 23 </ b> A and 23 </ b> B are arranged adjacent to each other in the circumferential direction of the outer cylinder 21, the notch portions face each other to form a V-shaped groove portion and form a magnetic flux converging portion 25. Since the same magnetic pole is adjacent to the radial direction and the circumferential direction of the outer cylinder 21, the magnetic flux concentrating part 25 concentrates the magnetic flux.

  Since the magnetic flux concentrates on the magnetic flux converging portion 25 formed by this notch, the magnetic flux density is improved and the torque can be increased. Moreover, the usage-amount of a permanent magnet can be decreased by providing the 2nd outer side magnet piece 23A, 23B with the notch part.

  Although the magnetic flux converging part 25 of this example is formed by the V-shaped groove part, it is not limited to this. For example, a recess may be formed by arranging the second outer magnet pieces not having a notch at intervals, and the recess may be used as a magnetic flux converging portion.

[Stator gear]
Next, the stator gear 7 will be described with reference to FIGS.
FIG. 5 is a perspective view of a stator gear of the magnetic gear device according to the present example.
6A is a cross-sectional view of the stator gear of the magnetic gear device according to the present example, and FIG. 6B is a cross-sectional view taken along the line CC shown in FIG. 6A.
7A is a plan view of a stator member of the stator gear according to this example, and FIG. 7B is a side view showing a state in which the stator members of the stator gear according to this example are stacked. FIG. 7C is a side view showing a state in which a fixing portion is interposed in the stator member of the stator gear of this example, and FIG. 7D is a plan view of the main body of the stator gear of this example.

  As shown in FIG. 5, the stator gear 7 includes a main body portion 41 and a base portion 47 that supports the main body portion 41. The stator gear 7 is attached to the first support plate 12 of the case 2 (see FIG. 1) and is disposed between the external gear 5 and the internal gear 6.

  The main body 41 is formed in a substantially cylindrical shape. The main body 41 is composed of a plurality of fixing portions 50 and a plurality of magnetic tooth portions 53. The plurality of magnetic tooth portions 53 are arranged at substantially equal intervals along the circumferential direction of the main body portion 41. That is, the plurality of magnetic tooth portions 53 are arranged concentrically with the cylindrical hole 21a of the external gear 5 (see FIG. 2). Moreover, since the several magnetic tooth part 53 is arrange | positioned at intervals with the adjacent magnetic tooth part 53, it is mutually independent.

  The magnetic tooth portion 53 is formed by laminating magnetic pieces 42b (see FIG. 7A) of the stator member 42 described later. The magnetic tooth portion 53 is skewed with respect to the axial direction of the main body portion 41. That is, the magnetic tooth portion 53 is twisted so as to rotate about the central axis of the main body portion 41.

  The fixing part 50 is interposed between the magnetic tooth parts 53. The fixing portion 50 is formed by a fixing member made of, for example, a synthetic resin.

  The base portion 47 is formed in a substantially disc shape. The base portion 47 is attached to one side of the main body portion 41 in the axial direction. As shown in FIGS. 6A and 6B, the base portion 47 has a through hole 47a and a recess 47b. The through hole 47 a is provided in the central portion of the base portion 47 and penetrates from the surface connected to the first support plate 12 of the base portion 47 to the opposite surface. The first rotating shaft 3 passes through the through hole 47a (see FIG. 1).

  The concave portion 47 b of the base portion 47 is provided around the through hole 47 a and is formed to be recessed from the surface facing the main body portion 41. The bearing 16 is disposed in the recess 47b (see FIG. 1).

Next, the manufacturing method of the main-body part 41 is demonstrated with reference to FIG. 7A-FIG. 7D.
First, the stator member 42 that forms the magnetic tooth portion 53 will be described.

  As shown in FIG. 7A, the stator member 42 is formed in a disk shape having a circular through hole at the center. The stator member 42 is made of a magnetic material. As the material of the stator member 42, for example, an electromagnetic steel plate or the like is used.

  The stator member 42 includes a connecting portion 42a, a magnetic piece 42b, and a groove portion 42c. The connecting portion 42 a of the stator member 42 is formed in a ring shape, and is provided inside the stator member 42 in the radial direction.

  The magnetic piece 42b of the stator member 42 is formed in a substantially rectangular plate shape. A plurality of magnetic pieces 42b are provided at intervals in the circumferential direction of the stator member 42. One end of the plurality of magnetic pieces 42b in the longitudinal direction is continuous with the connecting portion 42a. For this reason, the plurality of magnetic pieces 42b are connected via the connecting portion 42a.

  A groove 42c is formed between a plurality of magnetic pieces 42b provided in the circumferential direction of the stator member 42. Similar to the magnetic piece 42b, a plurality of the groove portions 42c are provided at intervals in the circumferential direction of the stator member 42.

  In addition, you may form a stator member so that the other end part of a magnetic piece may continue with a connection part. Thereby, a connection part is provided in the radial direction outer side of a stator member.

Next, the manufacturing process of the main body 41 will be described.
As shown in FIG. 7B, the stator member 42 described above is rotated little by little in the circumferential direction to stack a plurality of sheets. At this time, the plurality of magnetic pieces 42b are stacked while being shifted by the amount of rotation of the stator member 42. A magnetic tooth portion 53 is formed by the plurality of laminated magnetic pieces 42b.

  And as shown to FIG. 7C, the fixing | fixed part 50 is interposed in the groove part 42c. A plurality of fixing portions 50 are provided between the magnetic tooth portions 53 and connect adjacent magnetic tooth portions 53.

  Then, as shown to FIG. 7D, the connection part 42a is removed and the some magnetic tooth part 53 and the some fixing | fixed part 50 are left. Thereby, the cylindrical main-body part 41 is completed.

  In this example, the disk-shaped stator member 42 is rotated in the circumferential direction, and the magnetic pieces 42 b are shifted and laminated in the circumferential direction to form the magnetic tooth portion 53. As another example, the magnetic tooth portion may be formed by laminating the magnetic pieces 42b without rotating the disk-shaped stator member 42 in the circumferential direction.

  Further, when the plurality of stator members 42 are stacked, the space between the stator members 42 may be fixed by caulking, an adhesive, or the like, for example.

  In the conventional magnetic gear device (see Non-Patent Document 1 above), the low-speed rotor (external gear) and the high-speed rotor (internal gear) rotate in opposite directions, so eddy currents are generated in the magnetic tooth portion of the stator. Occur. When an eddy current is generated, an electromagnetic brake is generated against the rotation of the low-speed rotor (external gear) and the high-speed rotor (internal gear) according to Lenz's law, resulting in torque loss.

  On the other hand, in this example, the magnetic piece 42b is laminated, so that a fine gap is formed between the magnetic pieces 42b. This gap becomes a resistance of eddy current flowing in the axial direction of the main body 41 and can be cut off. As a result, torque loss due to eddy current in the magnetic gear device 1 can be reduced.

  If the stator gear is formed in a state where the magnetic tooth portions are integrally connected, the magnetic flux passes through the entire magnetic tooth portion. Further, in order to make the natural frequency of the magnetic poles several times the number of rotations of the gear, the magnetic tooth portion 53 of the stator gear 7 needs to be rigid. Therefore, it is preferable that the magnetic tooth portion 53 of the stator gear 7 has rigidity and is formed independently.

  In the stator gear 7 of the present example, a plurality of magnetic pieces 42b are formed on the stator member 42 continuously with the connecting portion 42a when the main body 41 is manufactured. Then, after the fixing portion 50 is interposed in the groove portion 42c of the stator member 42, the connecting portion 42a is removed. Thereby, the magnetic tooth part 53 will be in the independent state via the fixing | fixed part 50. FIG. At this time, the magnetic flux passing through the magnetic tooth portion 53 is blocked by the fixing portion 50 and cannot pass through the adjacent magnetic tooth portion 53. As a result, generation of eddy current can be reduced and torque loss can be reduced.

  And the fixing | fixed part 50 was interposed between the magnetic tooth parts 53 adjacent. Thereby, the rigidity of the plurality of magnetic tooth portions 53 can be increased, and deformation of the magnetic tooth portions 53 can be prevented.

  Furthermore, in this example, since the stator member 42 is rotated and laminated, the magnetic tooth portion 53 is twisted so as to rotate around the central axis of the main body portion 41. Thereby, a magnetic circuit is shifted | deviated and arrange | positioned in the circumferential direction of the main-body part 41, and the rapid change of the magnetic flux which passes along the magnetic tooth part 53 can be suppressed. Further, the attractive force and the repulsive force between the stator gear 7 and the first outer magnet pieces 22A and 22B, the second outer magnet pieces 23A and 23B of the outer gear 5, and the inner magnet pieces 32A and 32B of the inner gear 6 can be suppressed. . As a result, the cogging torque of the magnetic gear device 1 can be reduced.

  In addition, although the material of the stator member 42 of this example was demonstrated as an electromagnetic steel plate, it is not limited to this. As a material of the stator member 42, for example, a dust core may be used. The dust core has high electrical resistance because the iron powders are insulated from each other. When the stator member 42 is formed by a dust core, the electric resistance of the magnetic tooth portion 53 is increased, so that an eddy current is less likely to flow. As a result, torque loss due to eddy current in the magnetic gear device 1 can be reduced.

  Since the dust core is inexpensive, the material cost can be reduced by forming the stator member 42 with the dust core. Moreover, since the dust core is easy to mold, the stator member 42 can be easily manufactured.

  Considering the strength of the magnetic tooth portion 53 of the stator gear 7, it is necessary to have a cantilever shape in which one end (base end) is fixedly supported and the other end (tip end) is free. Therefore, the stator gear 7 is integrally formed by fixing one end of the main body portion 41 to the base portion 47. Accordingly, the magnetic flux leaks to the base portion 47 as well.

  On the other hand, in the magnetic gear device 1 of this example, the case 2, the first rotating shaft 3, and the second rotating shaft 4 are formed of a nonmagnetic material. As a result, the magnetic circuit passing from the internal gear 6 through the base portion 47 of the stator gear 7 can be interrupted.

  When the case 2 is formed of a conductive material, a current insulating material or a current insulating coating film is interposed between the base portion 47 of the stator gear 7 and the case 2, and the vortex flowing from the base portion 47 to the case 2. It is preferable to interrupt the current.

  In addition, the structure of an inner side magnet piece and the structure of an outer side magnet piece are not limited to the structure mentioned above. For example, the configuration of the inner magnet pieces may be the same as that of the first outer magnet pieces 22A and 22B and the second outer magnet pieces 23A and 23B. That is, it is good also as a structure which provides the magnetic flux converging part formed in V shape toward the outer side (stator gearwheel 7 side) of the inner cylinder 31 at the radial direction.

  The configuration of the outer magnet piece may be configured such that a plurality of magnet pieces magnetized in the radial direction of the outer cylinder 21 are adjacent to each other in the circumferential direction of the outer cylinder 21 and the magnetic poles are different.

  Further, the plurality of first magnet pieces magnetized in the radial direction of the outer cylinder 21 or the inner cylinder 31 are alternately arranged so that the magnetic poles are different from each other at intervals in the circumferential direction of the outer cylinder 21 or the inner cylinder 31. Then, the plurality of second magnet pieces magnetized in the circumferential direction of the outer cylinder 21 or the inner cylinder 31 are interposed between the plurality of first magnet pieces so that the same magnetic poles face each other with the first magnet piece interposed therebetween. Let Such a configuration can also be applied to the configuration of the inner magnet piece and the configuration of the outer magnet piece. Various other arrangements of magnet pieces can be applied.

2. Operation of Magnetic Gear Device Next, the operation of the magnetic gear device 1 will be described with reference to FIGS.
FIG. 8 is an explanatory diagram showing a state in which the first magnetic flux converging portions 25A and 25B of the external gear 5 face the first magnetic tooth portions 53A and 53B of the stator gear 7.

  As shown in FIG. 8, in the first magnetic tooth portions 53A and 53B, the side facing the inner magnet pieces 32Ba and 32Bb of the internal gear 6 is magnetized to become an N pole, and the opposite side (external gear 5 side) is S. It is the pole. The first magnetic flux converging portions 25A and 25B are opposed to the S poles of the first magnetic tooth portions 53A and 53B.

  In this state, the magnetic attraction generated between the inner magnet piece 32Ba and the first magnetic tooth portion 53A and between the inner magnet piece 32Bb and the first magnetic tooth portion 53A is not only in the radial direction but also in the circumferential direction. Is also balanced.

  FIG. 9 is an explanatory diagram of a state in which the second magnetic flux converging portions 25C and 25D of the external gear 5 face the second magnetic tooth portions 53C and 53D of the stator gear 7.

  When the internal gear 6 is rotated in the direction of the arrow R1 by the first rotating shaft 3 from the state shown in FIG. 8, the balance of the magnetic attractive force is lost, and the second magnetic tooth portion 53C and the inner magnet piece 32Ac and A circumferential attractive force is generated between the second magnetic tooth portion 53D and the inner magnet piece 32Ad. Accordingly, as shown in FIG. 9, the second magnetic flux converging portions 25C and 25D are opposed to the second magnetic tooth portions 53C and 53D.

  When the inner magnet pieces 32Ac, 32Ad face the second magnetic tooth portions 53C, 53D, the side of the second magnetic tooth portions 53C, 53D facing the inner magnet pieces 32Ac, 32Ad is magnetized to become the S pole, and vice versa. The side (external gear 5 side) is the N pole. As a result, the external gear 5 rotates in the direction of the arrow R2, and a balanced state as shown in FIG. 9 is obtained.

  FIG. 10 is an explanatory diagram showing a state in which the third magnetic flux converging portions 25E and 25F of the external gear 5 face the third magnetic tooth portions 53E and 53F of the stator gear 7.

  When the internal gear 6 is rotated in the direction of the arrow R1 by the first rotating shaft 3 from the state shown in FIG. 9, the balance of the magnetic attractive force is lost, the third magnetic tooth portion 53E and the inner magnet piece 32Be, and the first A circumferential attractive force is generated between the third magnetic tooth portion 53F and the inner magnet piece 32Bf. Thereby, as shown in FIG. 10, the third magnetic flux converging portions 25E and 25F face the third magnetic tooth portions 53E and 53F.

  When the inner magnet pieces 32Be and 32Bf face the third magnetic tooth portions 53E and 53F, the side of the third magnetic tooth portions 53E and 53F facing the inner magnet pieces 32Be and 32Bf is magnetized to become an N pole, and vice versa. The side (external gear 5 side) is the S pole. As a result, the external gear 5 rotates in the direction of the arrow R2, and a balanced state as shown in FIG. 10 is obtained.

  FIG. 11 is an explanatory diagram showing a state in which the fourth magnetic flux converging portions 25G and 25H of the external gear 5 face the fourth magnetic tooth portions 53G and 53H of the stator gear 7.

  When the internal gear 6 is rotated in the direction of the arrow R1 by the first rotating shaft 3 from the state shown in FIG. 10, the balance of the magnetic attractive force is lost, and the fourth magnetic tooth portion 53G and the inner magnet piece 32Ag A circumferential attractive force is generated between the fourth magnetic tooth portion 53H and the inner magnet piece 32Ah. Thereby, as shown in FIG. 11, the 4th magnetic flux converging parts 25G and 25H oppose the 4th magnetic tooth parts 53G and 53H.

  When the inner magnet pieces 32Ag, 32Ah face the fourth magnetic tooth portions 53G, 53H, the side of the fourth magnetic tooth portions 53G, 53H facing the inner magnet pieces 32Ag, 32Ah is magnetized to become an S pole, and vice versa. The side (external gear 5 side) is the N pole. As a result, the external gear 5 rotates in the direction of the arrow R2, and a balanced state as shown in FIG. 11 is obtained.

  FIG. 12 is an explanatory diagram of a state in which the fifth magnetic flux converging portions 25I and 25J of the external gear 5 face the fifth magnetic tooth portions 53I and 53J of the stator gear 7.

  When the internal gear 6 is rotated in the direction of the arrow R1 by the first rotating shaft 3 from the state shown in FIG. 11, the balance of the magnetic attractive force is lost, and the fifth magnetic tooth portion 53I and the inner magnet piece 32Bi A circumferential attractive force is generated between the magnetic tooth portion 53J and the inner magnet piece 32Bj. Thereby, as shown in FIG. 12, the fifth magnetic flux converging portions 25I and 25J face the fifth magnetic tooth portions 53I and 53J.

  When the inner magnet pieces 32Bi, 32Bj face the fifth magnetic tooth portions 53I, 53J, the side of the fifth magnetic tooth portions 53I, 53J facing the inner magnet pieces 32Bi, 32Bj is magnetized to become an N pole, and vice versa. The side (external gear 5 side) is the S pole. As a result, the external gear 5 rotates in the direction of the arrow R2, and a balanced state as shown in FIG. 12 is obtained.

  When the internal gear 6 is rotated in the direction of arrow R1 by the first rotating shaft 3, the external gear 5 rotates in the direction of arrow R2, and the state shown in FIG. 8 is changed to the state shown in FIG. The fifth magnetic tooth portions 53I and 53J are adjacent to the first magnetic tooth portions 53A and 53B in the direction of the arrow R1. By repeating the balance of the magnetic attractive force, the state of the magnetic gear device 1 changes. The external gear 5 rotates smaller than the internal gear 6 and rotates about 1/5 of the rotation angle of the internal gear 6 in this example.

3. Next, the arrangement of magnet pieces and the distribution of the magnetic flux density used in the magnetic gear device 1 of this example will be described with reference to FIG.
13A is an explanatory view showing the relationship between the arrangement of the inner magnet pieces 32A and 32B and the distribution of the magnetic flux density, and FIG. 13B is the arrangement of the first outer magnet pieces 22A and 22B and the second outer magnet pieces 23A and 23B and the magnetic flux density. It is explanatory drawing which shows distribution of.

  As shown in FIG. 13A, the inner magnet pieces 32 </ b> A and 32 </ b> B are arranged such that different magnetic poles are adjacent to each other in the circumferential direction of the tube hole 31 a of the inner tube 31. Since the inner magnet pieces 32A and 32B are magnetized in the radial direction of the inner cylinder 31, the magnetic flux density distribution in this arrangement is formed in a substantially trapezoidal shape.

  In this example, the pole pieces of the internal gear 6 having a smaller number of magnetic poles than the external gear 5 are arranged as shown in FIG. 13A. Since the inner magnet pieces 32A and 32B are alternately arranged in the circumferential direction of the internal gear 6 in the internal gear 6, a relatively large value of magnetic flux density can be obtained over a wide range, and the average value of the magnetic flux density Becomes larger. As a result, a large transmission torque can be obtained even with a small number of magnetic poles.

  As shown in FIG. 13B, the same magnetic poles of the first outer magnet pieces 22 </ b> A and 22 </ b> B and the second outer magnet pieces 23 </ b> A and 23 </ b> B are arranged adjacent to each other in the radial direction and the circumferential direction of the outer cylinder 21. In the arrangement of the first outer magnet pieces 22A and 22B and the second outer magnet pieces 23A and 23B, the magnetic flux is concentrated on the magnetic flux converging portion 25 formed in a V shape. The distribution of the magnetic flux density protrudes in a narrow range of the magnetic flux converging portion 25 where the magnetic flux collects.

  In this example, the pole pieces of the external gear 5 having more magnetic poles than the internal gear 6 are arranged as shown in FIG. 13B. Since the external gear 5 is provided with a large number of magnetic flux converging portions 25 at a narrow interval, a magnetic flux density having a large peak can be obtained continuously. Therefore, the average value of magnetic flux density can be increased, and a large transmission torque can be obtained.

  In the magnetic gear device 1 of this example, magnetic flux converging portions 25A to 25J, which are V-shaped grooves, are formed between the adjacent second outer magnet pieces 23A and 23B (see FIGS. 8 to 12). Magnetic flux concentrates on these magnetic flux converging portions 25A to 25J. Since the magnetic flux of the magnetic flux converging portions 25A to 25J passes through the narrow magnetic tooth portions 53A to 53J of the stator gear 7, the magnetic attractive force generated between the external gear 5 and the internal gear 6 can be increased. As a result, the magnetic gear device 1 can obtain a large transmission torque and improve the transmission efficiency.

  The present invention is not limited to the embodiment described above and shown in the drawings, and various modifications can be made without departing from the scope of the invention described in the claims.

  DESCRIPTION OF SYMBOLS 1 ... Magnetic gear apparatus, 2 ... Case, 3 ... 1st rotating shaft, 4 ... 2nd rotating shaft, 5 ... External gear, 6 ... Internal gear, 7 ... Stator gear, 11 ... bottom plate, 12 ... first support plate, 13 ... second support plate, 14 ... reinforcing piece, 16, 17, 18, 19 ... bearing, 21 ... outer cylinder, 21a ... cylinder hole, 22A, 22B ... first outer magnet piece, 23A, 23B ... second outer magnet piece, 25 ... magnetic flux converging part, 25A, 25B ... First magnetic flux converging unit, 25C, 25D ... second magnetic flux converging unit, 25E, 25F ... third magnetic flux converging unit, 25G, 25H ... fourth magnetic flux converging unit, 25I, 25J ... Fifth magnetic flux converging part, 31 ... inner cylinder, 31a ... cylinder hole, 32A, 32B ... inner magnet piece, 41 ... main body part, 42 ... Theta member, 42a ... coupling part, 42b ... magnetic piece, 42c ... groove part, 47 ... base part, 47a ... through hole, 47b ... concave part, 50 ... fixing part, 53 ... Magnetic tooth part, 53A, 53B ... First magnetic tooth part, 53C, 53D ... Second magnetic tooth part, 53E, 53F ... Third magnetic tooth part, 53G, 53H ... 4th magnetic tooth part, 53I, 53J ... 5th magnetic tooth part

Claims (6)

A cylindrical outer cylinder having a cylindrical hole; and an external gear having a plurality of outer magnet pieces attached to the inner periphery of the outer cylinder;
An internal gear disposed in the cylindrical hole of the external gear and having a cylindrical inner cylinder and a plurality of inner magnet pieces attached to an outer peripheral portion of the inner cylinder;
A stator gear disposed between the external gear and the internal gear,
The stator gear is
A main body having a plurality of magnetic teeth arranged concentrically with the cylindrical hole of the external gear, and a plurality of fixing portions provided between the plurality of magnetic teeth;
And a base part connected to the main body part.   The magnetic gear device according to claim 1, wherein the magnetic tooth portion is skewed with respect to an axial direction of the main body portion.   The magnetic gear device according to claim 1, wherein the magnetic tooth portion is formed of an electromagnetic steel plate.   The magnetic gear device according to claim 1, wherein the fixing portion is formed of a synthetic resin.   The magnetic gear device according to any one of claims 1 to 4, wherein the magnetic tooth portion is configured by laminating a plurality of magnetic pieces in an axial direction of the main body portion. The magnetic gear device according to claim 1, wherein the magnetic tooth portion is formed of a dust core.

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