JP2007082334A - Eddy current decelerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a plurality of divided members by circumferentially dividing a magnetic member, and ensure a sufficient strength in a coupling section between the divided members when the divided members are circumferentially linked as a ring. <P>SOLUTION: An eddy current decelerator is provided with an annular casing 3 facing a rotor 1 coupled to a rotating shaft, attached on the fixed side and comprising a nonmagnetic material, and the ring magnetic member 10 disposed at a portion facing the rotor 1 in the casing 3. A plurality of the divided members 15 are formed by circumferentially dividing the magnetic member 10. An extended protrusion 15a has a thickened end, and is provided at one circumferential end of the divided member 15. A fitted recess 15b is provided at the other end, and fitted to the extended protrusion 15a. The divided members 15 are circumferentially coupled as the ring by the extended protrusion 15a and the fitted recess 15b. A hole 12 is provided at the extended protrusion 15a in the divided member 15, and penetrates into the extended protrusion 15a in the axial direction. A bolt 13 is inserted into the hole 12. The divided members 15 are fixed to the casing 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an eddy current type speed reducer that assists a friction brake of a vehicle.

  For example, as shown in FIGS. 11 and 12, the eddy current type speed reducer includes a drum-like rotor 51 attached to a rotating shaft (not shown) and a fixed side (not shown). And a stator 52 disposed inward. The stator 52 is provided so as to face the inner peripheral surface of the rotor 51 and to be opposed to the inner peripheral surface of the outer magnet support ring 53 and to be rotatable in the circumferential direction. The inner magnet support ring 54 (inner ring) and an actuator (not shown) for rotating the inner magnet support ring 54 are provided.

  The outer magnet support ring 53 has a ring-shaped magnetic member 55 made of a magnetic material. As the magnetic member 55, a member formed by laminating a plurality of electromagnetic steel plates in the axial direction (laminated electromagnetic steel plate) or a member formed in a block shape is generally known. A plurality of permanent magnets 56 are embedded in the magnetic member 55 at predetermined intervals in the circumferential direction. Each permanent magnet 56 has magnetic poles at both ends in the circumferential direction, and the magnetic poles facing in the circumferential direction are set to have the same polarity.

  The inner magnet support ring 54 has a support ring 57 made of a magnetic material. A plurality of permanent magnets 58 are attached to the outer peripheral surface of the support ring 57 at a predetermined interval in the circumferential direction. Each permanent magnet 58 has magnetic poles at both ends in the radial direction, and is arranged by reversing the direction of the magnetic poles alternately in the circumferential direction.

  When decelerating and braking the rotating shaft (when braking is ON), as shown in FIG. 11, the magnetic poles facing the rotor 51 are disposed between the permanent magnets 56 of the outer magnet support ring 53 adjacent in the circumferential direction. The inner magnet support ring 54 is rotated by the actuator so that the permanent magnet 58 of the inner magnet support ring 54 having the same polarity as the magnetic pole of the permanent magnet 56 is positioned (braking position). As a result, a magnetic circuit connecting the N pole and the S pole is formed between the permanent magnets 56 and 58 of the magnet support rings 53 and 54 and the rotor 51. Thereby, an eddy current is generated in the rotor 51 by the relative rotation between the rotor 51 and the stator 52, and the rotating shaft is decelerated and braked.

  On the other hand, when releasing deceleration braking (when braking is OFF), as shown in FIG. 12, the magnetic poles facing the rotor 51 are disposed between the permanent magnets 56 of the outer magnet support ring 53 adjacent in the circumferential direction. The inner magnet support ring 54 is rotated by the actuator so that the permanent magnet 58 of the inner magnet support ring 54 that is different from the magnetic pole of the permanent magnet 56 is positioned (non-braking position). As a result, a short circuit magnetic circuit (blocking circuit for the rotor) connecting the N pole and the S pole is formed between the permanent magnet 56 of the inner magnet support ring 53 and the permanent magnet 58 of the outer magnet support ring 54, and the rotating shaft The deceleration braking is released.

  Such an eddy current reduction device is also described in Patent Document 1 and the like.

JP 2004-32927 A

  By the way, when a laminated electromagnetic steel sheet is used as the magnetic member 55 of the outer magnet support ring 53, since one electromagnetic steel sheet has a small radial width (difference between the outer diameter and the inner diameter) and is a large ring, If you make it, the yield of the material is bad.

  Therefore, in order to improve the yield of the material, it is conceivable to form the magnetic member 55 (electromagnetic steel plate) by dividing it into a plurality of parts in the circumferential direction and to connect these divided members in the circumferential direction to form a ring shape. In this way, when the divided members are connected to each other in the circumferential direction, it is necessary to sufficiently secure the strength of the coupling portion between the divided members.

  Therefore, an object of the present invention is to form a magnetic member into a plurality of parts in the circumferential direction and connect the divided members in the circumferential direction to form a ring shape. It is to secure enough.

  In order to achieve the above object, the invention of claim 1 is directed to an annular casing made of a non-magnetic material, which is attached to a fixed side facing a rotor coupled to a rotating shaft, and a portion of the casing facing the rotor. In the eddy current type speed reducer provided with the ring-shaped magnetic member provided in the above, the magnetic member is divided into a plurality of pieces in the circumferential direction to form divided members, and a tip end is formed at one end of the divided member in the circumferential direction. In addition to providing a large convex portion, a fitting concave portion that can be fitted to the large convex portion is provided at the other end, and the divided members are connected to each other in the circumferential direction by the large convex portion and the fitting concave portion to form a ring shape. An eddy current type characterized in that a hole is formed in the axial direction through the enormous convex portion of each divided member, and a bolt is inserted into the hole to fix each divided member to the casing. It is a reduction gear.

  The invention according to claim 2 is characterized in that, in a state where the divided members are connected to each other by the bulged convex portion and the fitting concave portion, a tubular pin is press-fitted into a hole provided in the bulged convex portion of the divided member, and the bulged convex portion The eddy current type speed reducer according to claim 1, wherein the eddy current type reduction device is enlarged and brought into close contact with the fitting recess.

  A third aspect of the present invention is the eddy current reduction device according to the first or second aspect, wherein the dividing member is formed by laminating a plurality of electromagnetic steel plates in the axial direction.

  A fourth aspect of the present invention is the eddy current reduction device according to any one of the first to third aspects, wherein a plurality of permanent magnets are embedded in the divided member at a predetermined interval in the circumferential direction.

  According to the present invention, when the magnetic member is divided into a plurality of parts in the circumferential direction to form divided members, and the divided members are connected to each other in the circumferential direction to form a ring shape, the strength of the joint between the divided members There is an excellent effect that a sufficient amount can be secured.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a side sectional view of an eddy current reduction device according to an embodiment of the present invention. FIG. 2 is a front cross-sectional view showing the eddy current reduction device according to the embodiment of FIG. 1 during braking. FIG. 3 is a front sectional view showing the non-braking state of the eddy current reduction device according to the embodiment of FIG.

  As shown in FIGS. 1 to 3, a drum-like rotor (braking drum) 1 in which an eddy current is generated is provided on an output flange (not shown) on a rotating shaft (not shown) such as an output shaft of a transmission. ) Is attached through. The rotor 1 is made of a conductive material and a magnetic material (ferromagnetic material, soft magnetic material, etc., the same applies hereinafter) (for example, low carbon steel, cast iron, etc., the same applies hereinafter). On the outer peripheral surface of the rotor 1, heat radiating fins 2 for radiating heat generated by eddy current are provided.

  Inside the rotor 1, a stator 3 attached to a fixed side (not shown) such as a casing of the transmission is disposed. The stator 3 is supported on the fixed side, and is disposed so as to face an annular casing 4 made of a nonmagnetic material (for example, a low magnetic permeability material such as aluminum, the same applies hereinafter) and an inner peripheral surface of the rotor 1. The first magnet support ring (outer magnet support ring) 5 provided integrally on the outer peripheral portion of the casing 4 facing the rotor 1 and the inner peripheral surface of the first magnet support ring 5 are arranged facing the casing 4. And a second magnet support ring (inner magnet support ring) 6 accommodated in a rotatable manner around the rotation axis, and an actuator (not shown) for rotating the second magnet support ring 6. ing.

  In the present embodiment, the casing 4 includes a cylindrical tubular body 7 and ring-shaped side covers 9 respectively attached to both sides (left and right sides in FIG. 1) of the tubular body 7 with bolts 8 or the like. ing.

  The first magnet support ring 5 is formed in a ring shape, and a magnetic member 10 made of a magnetic material, and magnetic poles that are embedded in the magnetic member 10 at a predetermined interval in the circumferential direction, are set to have the same polarity. A plurality of permanent magnets 11. The magnetic member 10 is bridged between the side covers 9 of the casing 4 and is fixed to the side cover 9 by mounting bolts 13 inserted into the mounting bolt holes 12. The mounting bolt 13 of this embodiment is made of a magnetic material. Each permanent magnet 11 is inserted into a permanent magnet hole 14 provided in the magnetic member 10 along the axial direction.

  The second magnet support ring 6 is formed in a ring shape, and is provided with a support ring 20 made of a magnetic material and an outer peripheral surface of the support ring 20 at a predetermined interval in the circumferential direction. And a plurality of permanent magnets 21 which are alternately reversed and aligned. The support ring 20 is attached to the outer peripheral side of the cylindrical body 7 of the casing 4 via the bush 22. Thrust washers 23 are provided on both sides of the support ring 20. The permanent magnets 21 of the second magnet support ring 6 are set to the same number as the permanent magnets 11 of the first magnet support ring 5.

  The actuator switches the relative position between the first magnet support ring 5 and the second magnet support ring 6 between a braking position and a non-braking position. The braking position of the present embodiment is such that the radially outer magnetic pole facing the rotor 1 is the same as the magnetic pole of the permanent magnet 11 of the first magnet support ring 5 between the permanent magnets 11 of the first magnet support ring 5 adjacent in the circumferential direction. The permanent magnet 21 of the second magnet support ring 6 which is a pole is opposed (see FIG. 2). The non-braking position of the present embodiment is such that the radially outer magnetic pole facing the rotor 1 is between the permanent magnet 11 of the first magnet support ring 5 and the permanent magnet 11 of the first magnet support ring 5 between the permanent magnets 11 of the first magnet support ring 5 adjacent in the circumferential direction. The permanent magnet 21 of the second magnet support ring 6 having a different polarity is opposed (see FIG. 3).

  When the rotating shaft is decelerated and braked (when braking is ON), as shown in FIG. 2, the first magnet support ring 5 and the second magnet support ring 6 are moved by the actuator so that the relative position becomes the braking position. The two magnet support ring 6 is rotated. As a result, a magnetic circuit connecting the N pole and the S pole is formed between the permanent magnets 11 and 21 of the magnet support rings 5 and 6 and the rotor 1. Thereby, an eddy current is generated in the rotor 1 by the relative rotation of the rotor 1 and the stator 3, and the rotating shaft is decelerated and braked.

  On the other hand, when releasing the deceleration brake (when the brake is OFF), as shown in FIG. 3, the actuator is arranged so that the relative position between the first magnet support ring 5 and the second magnet support ring 6 becomes the non-braking position. Thus, the second magnet support ring 6 is rotated. Then, a short-circuited magnetic circuit (blocking circuit for the rotor) that connects the N pole and the S pole is formed between the permanent magnet 11 of the first magnet support ring 5 and the permanent magnet 21 of the second magnet support ring 6. . At this time, since the magnetic fluxes of the permanent magnets 11 and 21 of the magnet support rings 5 and 6 do not reach the rotating shaft, the deceleration braking of the rotating shaft is released.

  Here, the feature of the eddy current type speed reducer of the present embodiment is that the magnetic member 10 is divided into a plurality of parts in the circumferential direction to form divided members 15, and the thick engraved bumps are formed at one end in the circumferential direction of each divided member 15. In addition to providing the portion 15a, the other end portion is provided with a fitting concave portion 15b that can be fitted to the large convex portion 15a, and the divided members 15 are connected to each other in the circumferential direction by the large convex portion 15a and the fitting concave portion 15b. In addition, the holes 12 are provided in the axial direction through the enormous convex portions 15a of the divided members 15, and bolts 13 are inserted into the holes 12 to fix the divided members 15 to the casing 3. is there.

  This will be specifically described below. The magnetic member 10 of the first magnet support ring 5 is divided into a plurality of parts (for example, six to eight parts) in the circumferential direction, and the divided members 15 are connected in the circumferential direction to form a ring shape. One end portion in the circumferential direction of each divided member 15 is provided with an enormous convex portion 15a having a thick tip (a radial width larger on the distal end side than the base portion) protruding outward in the circumferential direction. At the other end in the circumferential direction of each divided member 15, there is provided a fitting recess 15b that is recessed in substantially the same shape as the enormous protrusion 15a and can be fitted to the enormous protrusion 15a. In this embodiment, the enormous convex part 15a and the fitting concave part 15b are formed in a substantially circular shape. Further, the enormous convex portion 15 a and the fitting concave portion 15 b are provided at the substantially radial center of each divided member 15. The enormous convex portion 15a and the fitting concave portion 15b may be provided so as to be biased outward or inward with respect to the radial center of each divided member 15.

  The enormous convex portion 15 a of the dividing member 15 is provided with a mounting bolt hole 12 which is provided so as to penetrate in the axial direction and through which the mounting bolt 13 is inserted. In the present embodiment, the mounting bolt holes 12 are also provided between the permanent magnet holes 14 of the dividing member 15.

  A slight gap g (for example, a maximum of 0.5 mm) is provided between the adjacent divided members 15 from the coupling part (the enormous convex part 15a and the fitting concave part 15b) to the inner side or the outer side in the radial direction. The gap g is set so as to become smaller from the outer peripheral surface of the split member 15 toward the coupling portion side (radially inner side) or from the inner peripheral surface toward the coupling portion side (radial outer side). The gap g is impregnated with a sealing material to prevent water from entering.

  In the present embodiment, the dividing member 15 is composed of a laminate (laminated electromagnetic steel plate) of electromagnetic steel plates 16 formed by laminating a plurality of electromagnetic steel plates 16 (thin plates) in the axial direction. Moreover, in this embodiment, said enormous convex part 15a, fitting recessed part 15b, the attachment bolt hole 12, and the permanent magnet hole 14 are formed by pressing the electromagnetic steel plate 16. FIG.

  Hereinafter, an example of an assembly method of the magnetic member 10 of the first magnet support ring 5 will be described.

  First, the electromagnetic steel plate 16 is pressed into a predetermined shape, and the enormous convex portion 15a, the fitting concave portion 15b, the mounting bolt hole 12, and the permanent magnet hole 14 are formed. Next, the pressed electromagnetic steel sheet 16 is appropriately caulked in a substantially V shape (or substantially U shape) while being laminated in the thickness direction. The electromagnetic steel plate 16 is caulked to prevent the laminated electromagnetic steel plates 16 from being displaced from each other, and in this embodiment, the caulking portion 16a and the radial direction for preventing the electromagnetic steel plate 16 from being displaced in the circumferential direction. A caulking portion 16b for preventing slippage is provided (see FIGS. 4 and 5). The caulking portions 16a and 16b are not necessarily provided.

  Next, when the electromagnetic steel sheet 16 is laminated for one block of the dividing member 15, impregnation treatment (vacuum impregnation or the like) is performed between the electromagnetic steel sheets 16 of the dividing member 15. Further, the outer peripheral surface of the dividing member 15 is subjected to surface treatment (cationic coating or the like), and a waterproof sealing material is applied to the outer peripheral surface of the dividing member 15 and both ends in the circumferential direction. In addition, what is necessary is just to apply | coat a sealing member to the outer peripheral side straight part 15c of the circumferential direction both ends of the division member 15, and it is not necessarily required to apply | coat a sealing member to the inner peripheral side straight part 15d of the circumferential direction both ends.

  Next, as shown in FIG. 6, the divided members 15 are arranged along the outer peripheral surface of the cylindrical assembly jig 17 so that the enormous convex portions 15 a are fitted into the fitting concave portions 15 b of the adjacent divided members 15. Then, the divided members 15 are pressed by a hydraulic press 18 or the like, and the enormous convex portion 15a and the fitting concave portion 15b of each divided member 15 are fitted. The reason why the cylindrical assembly jig 17 is used is to ensure the roundness of the entire magnetic member 10. For this reason, a cylindrical assembly jig 17 having good dimensional accuracy and roundness of the outer peripheral surface is used. The assembly jig 17 may be pressed while holding the dividing member 15 from the inner peripheral side and the outer peripheral side thereof.

  Here, in this embodiment, the coupling | bonding (fit) between each division member 15 is comparatively loose, and the assembly which fits each division member 15 is easy. Particularly, in the present embodiment, the enormous convex portions 15a and the fitting concave portions 15b of the dividing member 15 are formed in a circular shape, and a gap g is provided between the adjacent dividing members 15 (see FIG. 4). Therefore, it is possible to provide flexibility in the displacement of the coupling portion between the adjacent divided members 15, and by aligning each divided member 15 along the outer peripheral surface of the cylindrical assembly jig 17, The degree can be easily adjusted.

  And in the state which connected each division member 15 with the enormous convex part 15a and the fitting recessed part 15b, a pin (not shown) was press-fitted in the attachment bolt hole 12 provided in the enormous convex part 15a of each division member 15. The enormous convex portion 15a is enlarged to the outer side in the radial direction (fitting concave portion 15b side) and is brought into close contact with the fitting concave portion 15b. As a result, the divided members 15 are firmly connected by tightly fitting the enormous convex portions 15a and the fitting concave portions 15b of the divided members 15 that were relatively loose during assembly to fit the divided members 15 together. can do. The pin is removed from the mounting bolt hole 12 before the mounting bolt 13 is inserted.

  The operation of this embodiment will be described.

  In the present embodiment, the magnetic member 10 of the first magnet support ring 5 facing the inner peripheral surface of the rotor 1 is divided into a plurality of pieces in the circumferential direction to form divided members 15, and one end in the circumferential direction of each divided member 15. In addition to providing a thick engraved convex portion 15a in the part, provided in the other end in the circumferential direction of each divided member 15 is provided a fitting recess 15b formed in substantially the same shape so as to be fitted with the enormous convex portion 15a, The divided members 15 are connected to each other in the circumferential direction by the enormous convex portions 15a and the fitting concave portions 15b to form a ring shape. By doing so, the divided members 15 can be reliably connected to each other without being disengaged in the circumferential direction due to the fitting of the enormous convex portion 15a having the thick tip and the fitting concave portion 15b. it can.

  Further, in the present embodiment, a mounting bolt hole 12 is provided in an axial direction through the enormous convex portion 15 a of each divided member 15, and the mounting bolt 13 is inserted into the mounting bolt hole 12 to connect each divided member 15 to the rotor 1. It is fixed to the casing 4 facing the inner peripheral surface. Therefore, each divided member 15 is fixed to the casing 4 by a mounting bolt 13 having one end in the circumferential direction inserted into the mounting bolt hole 12 of the enormous convex portion 15a of the divided member 15 itself, and the other end in the circumferential direction. Is fixed to the casing 14 by the mounting bolts 13 inserted through the mounting bolt holes 12 of the enormous convex portions 15a of the dividing members 15 adjacent in the circumferential direction.

  That is, each divided member 15 is provided with the mounting bolt holes 12 at both ends in the circumferential direction, and is fixed to the casing 14 with the mounting bolts 13 in the mounting bolt holes 12. 15 will not move. Therefore, each divided member 15 is firmly fixed to the casing 14, and the strength of the coupling portion between the divided members 15 and thus the strength of the entire magnetic member 10 can be sufficiently secured.

  Furthermore, in this embodiment, a pin is press-fitted into the mounting bolt hole 12 provided in the massive protrusion 15a of the divided members 15 in a state in which the divided members 15 are connected to each other by the massive protrusion 15a and the fitting recess 15b. The enormous convex portion 15a is enlarged and brought into close contact with the fitting concave portion 15b. By doing in this way, each division member 15 can be firmly connected and the intensity | strength of the coupling | bond part between each division member 15 can fully be ensured. Further, even if a pin is press-fitted into the mounting bolt hole 12 provided in the enormous convex portion 15a of the dividing member 15 and the enormous convex portion 15a is enlarged, the fitting of the thick enormous convex portion 15a and the fitting concave portion 15b is performed. Therefore, the divided members 15 are not detached in the circumferential direction.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various other embodiments can be adopted.

  For example, as shown in FIG. 7, the pin 30 used for enlarging the enormous convex part 15a of the magnetic member 10 (divided member 15) of the first magnet support ring 5 is formed in a tubular shape, and the pin 30 is formed as an enormous convex part. The mounting bolt 13 may be inserted into the pin 30 while being press-fitted into the mounting bolt hole 12 provided in 15a. In this case, the pin 30 is made of a magnetic material.

  Various modifications of the shape of the dividing member 15 can be considered. 8 and 9 show modified examples of the dividing member. In the example of FIG. 8, the bulge convex portion 35a of the magnetic member 10 (divided member 35) of the first magnet support ring 5 is formed in a certain shape (or dovetail shape), and the fitting concave portion 35b is fitted to the bulge convex portion 35a. It is formed in substantially the same shape so as to be possible. In the example of FIG. 9, the enormous protrusion 45a of the magnetic member 10 (divided member 45) of the first magnet support ring 5 is formed in a substantially square shape (substantially square in the illustrated example), and the fitting recess 45b is formed as an enormous protrusion 45a. It is formed in substantially the same shape so that it can be fitted.

  In addition, as shown in FIG. 10, on the inner peripheral surface of the magnetic member 10 (divided member 15) of the first magnet support ring 5, the permanent magnets 11 embedded in the magnetic member 10 are positioned on the inner side in the radial direction. A plurality of grooves 31 may be provided along the axial direction with a predetermined interval in the direction, and a plurality of magnetic pole pieces 32 separated by each groove 31 and extending radially inward may be provided with a predetermined interval in the circumferential direction. good.

  Furthermore, in the above-described embodiment, the magnetic member 10 (divided member 15) of the first magnet support ring 5 is made of a laminated electromagnetic steel plate. However, the present invention is not limited to this, and the magnetic member 10 (divided member 15) is a block body. It may consist of.

  In the above-described embodiment, the eddy current reduction device has been described in detail. However, the present invention can also be applied to members used in a generator, a motor, and the like.

It is side surface sectional drawing of the eddy current type reduction gear device which concerns on one Embodiment of this invention. It is front sectional drawing which shows the time of braking of the eddy current type reduction gear device which concerns on embodiment of FIG. It is front sectional drawing which shows the time of non-braking of the eddy current type | formula speed reducer which concerns on embodiment of FIG. It is front sectional drawing of a 1st magnet support ring. FIG. 5 is a cross-sectional view taken along line VV in FIG. 4. It is the schematic for demonstrating an example of the assembly method of a 1st magnet support ring. It is front sectional drawing of the 1st magnet support ring which shows a modification. It is front sectional drawing of the 1st magnet support ring which shows a modification. It is front sectional drawing of the 1st magnet support ring which shows a modification. It is front sectional drawing of the 1st magnet support ring which shows a modification. It is front sectional drawing which shows the time of braking of the conventional eddy current type reduction gear. It is front sectional drawing which shows the time of the non-braking of the conventional eddy current type reduction gear.

Explanation of symbols

1 Rotor 3 Casing 10 Magnetic Member 12 Mounting Bolt Hole (Hole)
13 Mounting bolt (bolt)
15, 35, 45 Dividing member 15a, 35a, 45a Enlarged convex part 15b, 35b, 45b Fitting concave part 30 Pin (tubular pin)

Claims (4)

Eddy current including an annular casing made of a non-magnetic material and a ring-shaped magnetic member provided at a portion of the casing facing the rotor, facing the rotor coupled to the rotating shaft. In the type reduction gear,
The magnetic member is divided into a plurality of parts in the circumferential direction to form divided members, and a thick engraved convex part is provided at one end in the circumferential direction of each divided member, and the enormous convex part can be fitted to the other end. A fitting concave portion is provided, and the divided members are connected to each other in the circumferential direction by the enormous convex portion and the fitting concave portion, to form a ring shape, and
An eddy current reduction device characterized in that a hole is formed through an enormous convex portion of each divided member in the axial direction, a bolt is inserted into the hole, and each divided member is fixed to the casing.   In a state where the divided members are connected to each other by the bulged convex portion and the fitting concave portion, a tubular pin is press-fitted into a hole provided in the bulged convex portion of the divided member, and the bulged convex portion is enlarged to fit the fitting. The eddy current type speed reducer according to claim 1, which is in close contact with the concave portion.   3. The eddy current reduction device according to claim 1, wherein the divided member is formed by laminating a plurality of electromagnetic steel plates in the axial direction. The eddy current reduction device according to any one of claims 1 to 3, wherein a plurality of permanent magnets are embedded in the divided member at predetermined intervals in the circumferential direction.

Images