Interaction force control device, electromagnetic brake, and rotary electric machine

Abstract

The invention relates to an interaction force control device, an electromagnetic brake and a rotary electric machine. The interaction force control device includes a first element including a first permanent magnet and a second element including a second permanent magnet and a coil. The relative positional relationship between the first element and the second element is variable. The mutual magnetic force of the first permanent magnet and the second permanent magnet generates an interaction force between the first element and the second element. The magnetic force of the second permanent magnet can be increased or decreased according to the magnetic force generated by the coil. The interaction force is controlled by changing the magnetic force generated by the coil.

Description

Technical Field

[0001] The present invention relates to an interaction force control device, an electromagnetic brake comprising the interaction force control device, and a rotating electric machine comprising the electromagnetic brake. Background Art

[0002] Patent Document 1 discloses a technology for generating a braking torque for maintaining the rotation state of a rotor by energizing.

[0003] [Prior art literature]

[0004] [Patent Document]

[0005] [Patent Document 1]: Japanese Unexamined Patent Application Publication No. H10-341590 Summary of the invention

[0006] [Problems to be Solved by the Invention]

[0007] The above technology has low versatility because it generates braking torque only by energizing.

[0008] Therefore, an object of the present invention is to provide an interaction force control device having good versatility, an electromagnetic brake including the interaction force control device, and a rotating electric machine including the electromagnetic brake.

[0009] [Methods of solving the problem]

[0010] The above-mentioned purpose is achieved through an interaction force control device, which includes: a first element, the first element includes a first permanent magnet; and a second element, the second element includes a second permanent magnet and a coil, wherein the relative position relationship between the first element and the second element is variable, the mutual magnetic force between the first permanent magnet and the second permanent magnet generates an interaction force between the first element and the second element, the magnetic force of the second permanent magnet can increase or decrease according to the magnetic force generated by the coil, and the interaction force is controlled by changing the magnetic force generated by the coil.

[0011] [Effects of the Invention]

[0012] According to the present invention, it is possible to provide an interaction force control device having excellent versatility, an electromagnetic brake including the interaction force control device, and a rotating electric machine including the electromagnetic brake. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a conceptual diagram of the interaction force control device;

[0014] Figure 2 is an external view of a rotating electrical machine;

[0015] Figure 3 is a side view of the rotor;

[0016] Figure 4 It is a three-dimensional diagram of the rotor;

[0017] Figure 5 is a view of the rotor observed along the axial direction;

[0018] Figure 6 yes Figure 2 A partial enlarged view of

[0019] Figure 7 is an illustrative view of a location where a permanent magnet can be mounted;

[0020] Figure 8 is a view showing a first modification example of the position of the permanent magnet;

[0021] Fig. 9 is a view showing a second modification of the position of the permanent magnet;

[0022] Fig.10 is an external view of a first modified example of the rotating electric machine;

[0023] Fig.11 yes Fig.10 A partial enlarged view of

[0024] Fig.12 is an external view of a second modification of the rotary electric machine;

[0025] Fig.13 yes Fig.12 A partial enlarged view of

[0026] Fig.14 is an external view of a third modification of the rotating electric machine. DETAILED DESCRIPTION

[0027] [Structure of the interaction force control device]

[0028] Figure 1: is a conceptual diagram of the interaction force control device 1. The interaction force control device 1 includes elements 10 and 30. Element 10 includes a permanent magnet m. Element 30 includes a coil C and a permanent magnet M. Element 10 is an example of a first element. Element 30 is an example of a second element. Permanent magnet m is an example of a first permanent magnet. Permanent magnet M is an example of a second permanent magnet. Elements 10 and 30 are arranged so that the relative position relationship is variable. For example, one of elements 10 and 30 is fixed, and the other is supported by a guide rail or the like so as to be able to move toward and away from one of the elements. Permanent magnet m and permanent magnet M are arranged so that different polarities face each other. Specifically, the S pole of permanent magnet m and the N pole of permanent magnet M face each other. Coil C is wound around permanent magnet M with the direction of the S pole and N pole arrangement of permanent magnet M as the central axis. In the unpowered state of coil C, an interaction force is generated between elements 10 and 30 by the mutual magnetic force of permanent magnets m and M. In Figure 1 In the example above, the interaction force is attractive.

[0029] By energizing the coil C so that it is in the energized state, the magnetic force of the permanent magnet M is weakened by the magnetic force generated by the coil C. This reduces the attractive force as the interaction force. In addition, by increasing the excitation current to the coil C, the magnetic force generated by the coil C and the magnetic force of the permanent magnet M are offset. This allows the interaction force to be eliminated. In addition, by increasing the energizing current to the coil C, the magnetic force generated by the coil C generates a repulsive force as the interaction force. In addition, by switching the direction of the energizing current to the coil C so that the coil C enters the reverse energizing state, the magnetic force generated by the coil C increases the attractive force as the interaction force. In this way, the direction and magnitude of the energizing current to the coil C are controlled to change the magnetic force generated by the coil C, thereby controlling the interaction force in various ways. Therefore, the mechanism of the interaction force control device 1 is used in various devices, and the interaction force control device 1 has good versatility. For example, the mechanism of the interaction force control device 1 is used for an electromagnetic brake or a rotating electric machine. Note that, Figure 1 It is intended to explain the concept of the interaction force control device 1 and does not take into account practical design limitations such as magnetic short circuits of the permanent magnets M and m.

[0030] The element 10 may be a member made of a magnetic material, such as an iron core without a permanent magnet m. In this case, an attractive force due to magnetic force acts between the element 10 and the permanent magnet m.

[0031] This attractive force is reduced or eliminated by the magnetic force generated by coil C.

[0032] [Structure of rotating electric machine]

[0033] Figure 21a is an external view of the rotary electric machine 1a. The rotary electric machine 1a is a hybrid stepping motor. The rotary electric machine 1a has a function of an electromagnetic brake using an interaction force control device. The rotary electric machine 1a includes a rotor 10a, a stator core 30a, coils Ca to Ch, and permanent magnets Ma to Mh. Figure 2 The axial center A is shown as the rotation center axis of the rotor 10a. Therefore, Figure 2 1 is a view of the rotating electrical machine 1a as viewed from the direction of the axial center A. The rotor 10a is of an inner rotor type.

[0034] Figure 3 is a side view of the rotor 10a. Figure 4 It is a perspective view of the rotor 10a. Figure 5 1 is a view of the rotor 10a observed in the direction of the axial center A. The rotor 10a includes a shaft 11, iron cores 12a and 12b, and a permanent magnet mA. The permanent magnet mA is arranged between the iron cores 12a and 12b and in contact with the iron cores 12a and 12b. The iron cores 12a and 12b and the permanent magnet mA are all in the shape of a circular plate. The permanent magnet mA is magnetized to have different polarities in the direction of the axial center A. Therefore, the polarity of the iron core 12a and the polarity of the iron core 12b are different from each other. For example, the iron core 12a is magnetized to the S pole, and the iron core 12b is magnetized to the N pole. The permanent magnet mA is an example of a first permanent magnet.

[0035] A plurality of pole teeth 13a are formed on the outer peripheral surface of the core 12a at a predetermined pitch. A plurality of pole teeth 13b are formed on the outer peripheral surface of the core 12b at a predetermined pitch. Here, the pitch of the pole teeth 13a and the pitch of the pole teeth 13b are the same. The core 12a and the core 12b are fixed to the shaft 11 with a deviation of half a pitch. Therefore, as Figure 5 As shown, the pole teeth 13a are located between adjacent pole teeth 13b when viewed from the direction of the axial center A. Similarly, the pole teeth 13b are located between adjacent pole teeth 13a.

[0036] Figure 2 The stator core 30a shown is formed by stacking a plurality of thin plates made of electromagnetic steel sheets in the thickness direction. The stator core 30a includes a yoke 31 and teeth 33a to 33h. The yoke 31 has a generally annular shape surrounding the rotor 10a. The yoke 31 includes an outer peripheral surface 311 and an inner peripheral surface 312. When viewed from the direction of the axial center A, the outer peripheral surface 311 has a generally rectangular shape. If the teeth 33a to 33h are not present in the yoke 31, the inner peripheral surface 312 has a generally circular shape when viewed from the direction of the axial center A.

[0037] The teeth 33a to 33h protrude radially inward from the inner peripheral surface 312 of the yoke 31. Therefore, each end of the teeth 33a to 33h faces the outer peripheral surface of the rotor 10a. The teeth 33a to 33h are arranged at equal angular intervals in the circumferential direction. Figure 2 The center lines La to Lh of the teeth 33a to 33h are shown respectively. The center lines La to Lh pass through the axial center A and are parallel to the radial direction. The center lines La to Ld are respectively the same as the center lines Le to Lh. The coils Ca to Ch are respectively wound around the teeth 33a to 33h via insulators not shown. When the coils Ca to Ch are energized, magnetic flux is generated to the yoke 31 and the teeth 33a to 33h as the main magnetic circuit.

[0038] Permanent magnets Ma to Mh are respectively arranged on the root side of the yoke 31 near the teeth 33a to 33h. Permanent magnets Ma to Mh are respectively arranged at positions overlapping with center lines La to Lh. Permanent magnets Ma to Mh are respectively located on the radial outside of coils Ca to Ch. Permanent magnets Ma to Mh are inserted into a plurality of holes preformed in the stator core 30a. Permanent magnets Ma to Mh have the same size and shape. In each of the permanent magnets Ma to Mh, one of the S poles and the N poles faces radially inward, while the other of the S poles and the N poles faces radially outward. Specifically, each of permanent magnets Ma, Mb, Me and Mf has an N pole facing radially inward and an S pole facing radially outward. In each of permanent magnets Mc, Md, Mg and Mh, the S pole faces the inner side in the radial direction, and the N pole faces the outer side in the radial direction. In other words, the polarity of the radial inner side of two permanent magnets opposite to each other with the axial center A between them is the same. Each of the permanent magnets Ma to Mh is an example of a second permanent magnet. Each of the permanent magnets Ma to Mh and the yoke 31 correspond to a second element. Therefore, the stator core 30a includes eight second elements.

[0039] When the coils Ca to Ch are in an unpowered state where no current is applied, the teeth 33a, 33b, 33e and 33f are magnetized to the N pole by the permanent magnets Ma, Mb, Me and Mf. Similarly, the teeth 33c, 33d, 33g and 33h are magnetized to the S pole by the permanent magnets Mc, Md, Mg and Mh.

[0040] Figure 6 yes Figure 2A partially enlarged view. The tooth portion 33a is taken as an example for explanation. The tooth portion 33a includes a rod portion 331 and a flange portion 333. The rod portion 331 extends radially inward from the inner circumferential surface 312 of the yoke portion 31, and has a substantially constant width in a direction perpendicular to the center line La. The flange portion 333 is continuous with the rod portion 331 radially inward, and is larger than the rod portion 331 in the circumferential direction. A plurality of pole teeth 334 are formed on the surface of the flange portion 333 facing the rotor 10a in the circumferential direction. Specifically, six pole teeth 334 are formed in each of the tooth portions 33a to 33h. The pitch of the pole teeth 334 is narrower than each pitch of the pole teeth 13a and 13b. The pole teeth 334 are examples of stator pole teeth.

[0041] The coil Ca is wound around the rod portion 331 .

[0042] A case where the coils Ca to Ch are in a non-energized state will be described. Figure 6 As shown, the pole tooth 13a faces the pole tooth 334 of the tooth portion 33a in the radial direction in a state slightly displaced in the clockwise direction. The tooth portion 33a is magnetized to the N pole, and the pole tooth 13a is magnetized to the S pole. Therefore, a magnetic circuit is formed therebetween, and an attractive force is generated therebetween. That is, the tooth portion 33a applies a counterclockwise force and a radially outward force to the rotor 10a. Similarly, the pole tooth 13a faces the pole tooth 334 of the tooth portion 33b in the radial direction in a state slightly displaced in the counterclockwise direction. Therefore, the tooth portion 33b applies a clockwise force and a radially outward force to the rotor 10a. Here, the counterclockwise force and the clockwise force are offset.

[0043] Similarly, the counterclockwise force acting on the rotor 10a through the tooth portion 33c and the clockwise force acting on the rotor 10a through the tooth portion 33d cancel each other. The same applies to the tooth portions 33e to 33h. As a result, the rotor 10a is subjected to a radially outward force, and the rotor 10a is kept in a stopped state. As described above, when the coils Ca to Ch are in a non-energized state, the rotor 10a and the stator core 30a are constrained so that the relative positional relationship between them does not change. That is, the brake acts on the rotor 10a.

[0044] Similarly, assuming that the rotor 10a is Figure 2 The state is offset by half the pitch of each pole tooth 13a and 13b. In this case, the pole tooth 13b faces the pole tooth 334 of the tooth portion 33a in the radial direction while being slightly displaced in the clockwise direction. Therefore, the tooth portion 33a applies a clockwise force and a radially outward force to the rotor 10a. Similarly, the pole tooth 13b faces the pole tooth 334 of the tooth portion 33b in the radial direction while being slightly displaced in the counterclockwise direction. Therefore, the tooth portion 33b applies a counterclockwise force and a radially outward force to the rotor 10a. The clockwise force and the counterclockwise force cancel each other out. The same applies to the teeth 33c to 33h. Therefore, even when the rotor 10a is shifted from Figure 2When the state shown is offset by half a pitch, the brake acts on the rotor 10a in the non-energized state. As described above, the rotor 10a stops at Figure 2 The position shown is offset by a position of half the pitch of each of the pole teeth 13a and 13b.

[0045] In this way, when the coils Ca to Ch are in an unpowered state, the rotor 10a stops and is maintained. Therefore, in the case of an application in which the rotating electric machine 1a is used for a long standby time to stop the rotor 10a, it is possible to suppress power consumption. In addition, for example, even when the power supply is lost, the rotor 10a stops, thereby providing good safety. In addition, by forming a plurality of holes in the stator core 30a and inserting the permanent magnets Ma to Mh into the plurality of holes, respectively, a function of stopping the rotor 10a without energizing the stator core 30a can be provided. Therefore, the increase in the manufacturing cost of the rotating electric machine 1a is suppressed. In addition, compared with the case in which the rotor 10a is stopped using a friction brake mechanism, for example, the rotating electric machine 1a does not require a movable part or a wear part, and has good durability. In addition, the rotor 10a stops at each half of the pitch of each pole tooth 13a and 13b, and the resolution of the stop position is improved.

[0046] In addition, when all coils Ca to Ch are set to the energized state to offset the magnetic flux of the permanent magnets Ma to Mh, the attraction between the rotor 10a and the stator core 30a is released. Therefore, the rotor 10a is in a free rotation state in which the rotor 10a rotates freely. In addition, by setting the energization of the coils Ca to Ch to the energized state and the non-energized state, respectively, a brake weaker than the brake applied when the coils Ca to Ch are not excited can also be applied. For example, only four coils Ca, Cc, Ce and Cg among the coils Ca to Ch are excited. The current of the coils Ca to Ch can be individually set to an intermediate amount between the energized state and the non-energized state. For example, the current of the four coils Cb, Cd, Cf and Ch among the coils Ca to Ch is set to 50% of the current in the energized state when the coil is not used as a brake, and the current of the other four coils is set to 100%. In this way, the action of the brake is adjusted by individually changing the energization of the coils Ca to Ch.

[0047] By controlling the energization of the coils Ca to Ch, the rotor 10a rotates in addition to regulating the action of the brake. Figure 2 In the state of , the coils Cb, Cd, Cf and Ch are set to the non-energized state, and the coils Ca, Cc, Ce and Cg are set to the energized state so as to cancel the magnetic flux of the permanent magnets Ma, Mc, Me and Mg. As a result, the attraction between each of the teeth 33a, 33c, 33e and 33g and the rotor 10a is released, and the rotor 10a rotates clockwise.

[0048] In the rotor 10a, Figure 2 In a state where the state is offset by half of each pitch of the pole teeth 13a and 13b, the coils Ca, Cc, Ce and Cg are set to a non-energized state, and the coils Cb, Cd, Cf and Ch are set to an energized state so as to cancel the magnetic flux of the permanent magnets Mb, Md, Mf and Mh. As a result, the attraction between each of the tooth portions 33b, 33d, 33f and 33h and the rotor 10a is released, and the rotor 10a rotates clockwise. By switching between the non-energized state and the energized state at a predetermined timing in this way, the rotation of the rotor 10a continues.

[0049] The coils Ca to Ch can be reversely excited to enhance the magnetic flux of each permanent magnet Ma to Mh. This can further increase the interaction force, that is, the attraction force between the rotor 10a and the stator core 30a, compared to the non-energized state. This makes it possible to more strongly constrain the rotor 10a and the stator core 30a.

[0050] The teeth 33a are formed symmetrically with respect to the center line La. As described above, the permanent magnet Ma is disposed at a position overlapping with the center line La. Figure 6 , the thickness T and width W of the permanent magnet Ma are shown. The thickness T is the thickness of the permanent magnet Ma in the direction parallel to the center line La. The width W is the width of the permanent magnet Ma in the direction perpendicular to the center line La. Figure 6 As shown, the width W is longer than the thickness T. Therefore, the permanent magnet Ma is arranged at a position overlapping with the center line La, and the width W is longer than the thickness T. Therefore, the magnetic short circuit of the rod portion 331 serving as the magnetic path of the magnetic flux of the permanent magnet Ma is reduced, and thus the magnetic force of the permanent magnet Ma is effectively applied to the rotor 10a. Therefore, the rotor 10a stops and is held. Each length of the permanent magnets Ma to Mh in a direction parallel to the axial center A is substantially the same as the thickness of the stator core 30a in a direction parallel to the axial center A.

[0051] Similar to the permanent magnet Ma, the permanent magnets Mb to Mh are respectively arranged at positions overlapping the center lines Lb to Lh, and each of the permanent magnets Mb to Mh has a width longer than its thickness. As described above, the magnetic force of the permanent magnets Ma to Mh is effectively applied to the rotor 10a to stop the rotor 10a.

[0052] The permanent magnets Ma to Mh are separated from the coils Ca to Ch outward in the radial direction, respectively. Therefore, even after the coils Ca to Ch are wound around the stator core 30a, the permanent magnets Ma to Mh are inserted into the corresponding holes of the stator core 30a. This improves the assembly workability of the rotary electric machine 1a.

[0053] Figure 7 : is an explanatory view of the position where the permanent magnet Ma is installed. Figure 7The thickness T of the permanent magnet Ma starting from the distal end surface of the flange portion 333, the thickness T of the permanent magnet Ma starting from the outer peripheral surface 311 of the yoke portion 31, and the mountable range R are shown. The mountable range R is illustrated as a length obtained by excluding the thickness T starting from the distal end surface of the flange portion 333 and the thickness T starting from the outer peripheral surface 311 from the distal end surface of the flange portion 333 to the length of the outer peripheral surface 311 in the direction of the center line La. The permanent magnet Ma is set within the mountable range R. In other words, the permanent magnet Ma is separated from the distal end surface of the flange portion 333 outward by the thickness T or more of the permanent magnet Ma in the radial direction, and is separated from the outer peripheral surface 311 inward by the thickness T or more of the permanent magnet Ma in the radial direction. Therefore, the magnetic force of the permanent magnet Ma is effectively applied to the rotor 10a by using the stator core 30a, and the strength of the stator core 30a is also ensured.

[0054] The above conditions are also satisfied for the permanent magnets Mb to Mh. That is, the permanent magnets Mb to Mh are separated from the distal end surfaces of the teeth 33b to 33h outwardly by a thickness of T or more in the radial direction, and are separated from the outer peripheral surface 311 inwardly by a thickness of T or more in the radial direction, respectively. Therefore, the magnetic force of the permanent magnets Mb to Mh is effectively applied to the rotor 10a by using the stator core 30a, and the strength of the stator core 30a is also ensured.

[0055] Figure 8 is a view showing a first modification example of the position of the permanent magnet. Figure 8 Corresponds to Figure 6 . Figure 8 The width W1 of the permanent magnet Ma1 shown is narrower than the width W of the permanent magnet Ma described above, but the thickness T is the same. The permanent magnet Ma1 is arranged at a position overlapping with the coil Ca. The permanent magnets Mb to Mh may be arranged at a position overlapping with the coil Ca. Figure 8 At the same position of the permanent magnet Ma1.

[0056] Fig. 9 is a view showing a second modification of the position of the permanent magnet. Fig. 9 Corresponds to Figure 6 . Fig. 9 The width W2 of the permanent magnet Ma2 shown is narrower than the width W of the permanent magnet Ma, but the thickness T is the same. The permanent magnet Ma2 is arranged radially inward of the coil Ca. The permanent magnets Mb to Mh can be arranged at the same Fig. 9 At the same position of permanent magnet Ma2.

[0057] [Configuration of First Modification of Rotating Electric Machine]

[0058] Fig.10 is an external view of a first modified example of the rotating electric machine. Fig.10 Corresponds to Figure 2The rotating electric machine 1b is different from the above-mentioned rotating electric machine 1a in that four permanent magnets Ma, Mc, Me and Mg are provided in the stator core 30b. Therefore, the manufacturing cost of the stator core 30b of the rotating electric machine 1b is reduced compared with the above-mentioned stator core 30a provided with eight permanent magnets Ma to Mh. Fig.11 yes Fig.10 A partial enlarged view of . Fig.11 Corresponds to Figure 6 .

[0059] A case where the coils Ca to Ch are in a non-energized state will be described. Fig.11 As shown, the pole tooth 13a faces the pole tooth 334 of the tooth portion 33a in the radial direction. The tooth portion 33a is magnetized to the N pole, and the pole tooth 13a is magnetized to the S pole. Therefore, a magnetic circuit is formed therebetween, and an attractive force is generated. The same applies to the tooth portion 33e. In this state, with respect to the tooth portions 33c and 33g, the pole tooth 13b and the pole tooth 334 face each other in the radial direction. The tooth portions 33c and 33g are magnetized to the S pole, and the pole tooth 13b is magnetized to the N pole. Therefore, a magnetic circuit is formed therebetween, and an attractive force is generated. As a result, the brake acts on the rotor 10a. In addition, the coils Ca, Cc, Ce and Cg can be set to a reverse energization state to enhance the magnetic flux of the permanent magnets Ma, Mc, Me and Mg.

[0060] The stator core 30a is provided with permanent magnets Ma to Mh, and the stator core 30b is provided with four permanent magnets Ma, Mc, Me and Mg, but the present invention is not limited thereto. For example, only one of the permanent magnets Ma to Mh may be provided. In addition, only two of the permanent magnets Ma to Mh may be arranged to face each other, with the axial center A inserted between them. For example, only permanent magnets Ma and Me may be provided.

[0061] [Configuration of Second Modification of Rotating Electric Machine]

[0062] Fig.12 is an external view of a second modification of the rotating electric machine. Fig.12 Corresponds to Figure 2 . The rotating electric machine 1c is different from the above-mentioned rotating electric machine 1a in that four permanent magnets Mha, Mbc, Mde, Mfg are provided in the yoke 31 of the stator core 30c. The permanent magnet Mha is provided in the yoke 31 between the teeth 33h and 33a in the circumferential direction. The permanent magnet Mbc is provided in the yoke 31 between the teeth 33b and 33c in the circumferential direction. The permanent magnet Mde is provided in the yoke 31 between the teeth 33d and 33e in the circumferential direction. The permanent magnet Mfg is provided in the yoke 31 between the teeth 33f and 33g in the circumferential direction.

[0063] Fig.12The dividing lines Lha, Lbc, Lde and Lfg passing through the axial center A and parallel to the radial direction are shown. The permanent magnets Mha, Mbc, Mde and Mfg are respectively arranged at positions overlapping with the dividing lines Lha, Lbc, Lde and Lfg. The dividing line Lha passes through the middle of the adjacent center lines Lh and La. The dividing line Lbc passes through the middle of the adjacent center lines Lb and Lc. The dividing line Lde passes through the middle between the adjacent center lines Ld and Le. The dividing line Lfg passes through the middle between the adjacent center lines Lf and Lg. The dividing lines Lha and Lbc are respectively the same as the dividing lines Lde and Lfg. Therefore, the angle between the dividing line Lha and the center line Lh, the angle between the dividing line Lha and the center line La, the angle between the dividing line Lbc and the center line Lb, the angle between the dividing line Lbc and the center line Lc, the angle between the dividing line Lde and the center line Ld, the angle between the dividing line Lde and the center line Le, the angle between the dividing line Lfg and the center line Lf, and the angle between the dividing line Lfg and the center line Lg are the same.

[0064] In each of the permanent magnets Mha, Mbc, Mde, and Mfg, one of the S pole and the N pole faces one side in the circumferential direction, and the other of the S pole and the N pole faces the other side in the circumferential direction. Specifically, the N pole of each of the permanent magnets Mha and Mde is oriented in the clockwise direction, and the S pole thereof is oriented in the counterclockwise direction. In each of the permanent magnets Mbc and Mfg, the N pole is oriented in the counterclockwise direction, and the S pole is oriented in the clockwise direction.

[0065] In the non-energized state where the coils Ca to Ch are not energized, the teeth 33h and 33a are magnetized to the S pole and the N pole respectively by the permanent magnet Mha. Similarly, the teeth 33b and 33c are magnetized to the N pole and the S pole by the permanent magnet Mbc, the teeth 33d and 33e are magnetized to the S pole and the N pole by the permanent magnet Mde, and the teeth 33f and 33g are magnetized to the N pole and the S pole by the permanent magnet Mfg. In this way, one permanent magnet magnetizes two teeth. Therefore, compared with the above-mentioned stator core 30a provided with eight permanent magnets Ma to Mh, the manufacturing cost of the stator core 30c of the rotary electric machine 1c is reduced.

[0066] Fig.13 yes Fig.12 A partial enlarged view of .

[0067] The permanent magnet Mha will be described as an example. The thickness T is the thickness of the permanent magnet Mha in a direction perpendicular to the dividing line Lha. The width W is the width of the permanent magnet Mha in a direction parallel to the dividing line Lha. The permanent magnet Mha is arranged so that the boundary line between the S pole and the N pole of the permanent magnet Mha overlaps the dividing line Lha.

[0068] Therefore, the teeth 33h and 33a are effectively magnetized to different polarities by the permanent magnet Mha. The same applies to the permanent magnets Mbc, Mde, and Mfg.

[0069] The stator core 30c is provided with permanent magnets Mha, Mbc, Mde and Mfg, but the present invention is not limited thereto. For example, only one of the permanent magnets Mha, Mbc, Mde and Mfg may be provided. Alternatively, only two of the permanent magnets Mha, Mbc, Mde and Mfg may be provided to face each other with the axial center A between them. For example, only permanent magnets Mha and Mde may be provided.

[0070] [Configuration of Third Modification of Rotating Electric Machine]

[0071] Fig.14 is an external view of a third modification of the rotating electric machine. Fig.14 Corresponds to Figure 2 The rotating electric machine 1e is a synchronous motor. The rotor 10b includes a shaft 11, an iron core 12, and permanent magnets ma to md. The iron core 12 has a cylindrical shape. The shaft 11 is inserted into a hole in the center of the iron core 12, and the iron core 12 is fixed to the shaft 11. The rotor 10b is rotatably supported by the shaft 11. The rotor 10b is an inner rotor type.

[0072] Permanent magnets ma to md are arranged on the outer peripheral surface of the core 12. Each of the permanent magnets ma to md is formed into an arc shape. The permanent magnets ma to md have the same size and shape. In each of the permanent magnets ma to md, one of the S pole and the N pole faces inward in the radial direction, and the other of the S pole and the N pole faces outward in the radial direction. Specifically, each of the permanent magnets ma and mc has a radially inward N pole and a radially outward S pole. In each of the permanent magnets mb and md, the S pole is radially inward and the N pole is radially outward. Fig.14 Only the outer polarity of the permanent magnets ma to md is shown. In this way, the outer peripheral surface of the rotor 10b is magnetized to four polarities at equal intervals in the circumferential direction. Each of the permanent magnets ma to md is an example of a first permanent magnet. Each of the permanent magnets ma to md and the iron core 12 corresponds to a first element. Therefore, the rotor 10b includes four first elements.

[0073] The stator core 30d includes a yoke 31d and teeth 34a to 34f. Permanent magnets Mb, Mc, Me and Mf are arranged on the yoke 31d of the stator core 30d. Permanent magnets Mb, Mc, Me and Mf are arranged at positions corresponding to teeth 34b, 34c, 34e and 34f, respectively. When the coils Ca to Cf are in an unpowered state, the teeth 34b, 34c, 34e and 34f are magnetized to S pole, N pole, S pole and N pole, respectively. Therefore, the rotor 10b is braked. Different from the above-mentioned teeth 33a to 33h, the teeth 34a to 34f are provided with pole teeth at the distal end portion.

[0074] Furthermore, by controlling the energization of the coils Cb, Cc, Ce, and Cf, the magnetic fluxes of the permanent magnets Mb, Mc, Me, and Mf are canceled out or increased at a predetermined timing, thereby generating a rotational force in the rotor 10b.

[0075] The above-mentioned rotor 10b has four different polarities in the circumferential direction, but the present invention is not limited thereto, and the rotor 10b may have magnetic poles that are an integral multiple of 2. For example, the outer peripheral surface of the rotor 10b may be magnetized to eight polarities at equal intervals in the circumferential direction. In this case, for example, the stator core 30d may include twelve teeth and a coil wound around each tooth.

[0076] Each of the stator cores 30a, 30b, and 30c includes eight tooth portions 33a to 33h, and the stator core 30d includes six tooth portions 34a to 34f. However, the number of tooth portions is not limited thereto. Fig.14 In the case of the synchronous motor shown, the braking position accuracy of the rotor is improved by increasing the number of poles of the rotor 10b and the number of slots of the stator core 30a.

[0077] Already referred to Figures 2 to 14 A rotating electric machine including an electromagnetic brake is described, but the present invention is not limited thereto. The electromagnetic brake may not have the function of rotating the electric machine. That is, the electromagnetic brake may not have the purpose of rotating the rotor.

[0078] Although the exemplary embodiments of the present invention have been described in detail, the present invention is not limited to the above-mentioned embodiments, and other embodiments, variations and changes may be made without departing from the scope of the present invention.

Claims

1. An interaction force control device, comprising: a first element, the first element comprising a first permanent magnet; as well as a second element, the second element comprising a second permanent magnet and a coil, in, The relative positional relationship between the first element and the second element is variable. The mutual magnetic force between the first permanent magnet and the second permanent magnet generates an interaction force between the first element and the second element, The magnetic force of the second permanent magnet can be increased or decreased according to the magnetic force generated by the coil, and The interaction force is controlled by varying the magnetic force generated by the coil.

2. The interaction force control device according to claim 1, wherein: said first element being part of a rotor of a rotating electric machine, said second element being part of a stator of said rotating electric machine, The coils are stator windings of the rotating electric machine, and The relative positional relationship varies in a circumferential direction around an axis of the rotor.

3. An electromagnetic brake comprising the interaction force control device according to claim 2, in, When the coil is in an unpowered state, the rotor and the stator are constrained by the interaction force so that the relative position relationship remains unchanged, and When the coil is in an energized state, the magnetic force generated by the coil and the magnetic force of the second permanent magnet cancel each other, and the rotor and the stator are released by the interaction force.

4. The electromagnetic brake according to claim 3, wherein: When the coil is in the reverse energized state, the interaction force increases, and the rotor and the stator are more strongly constrained than when the coil is in the non-energized state.

5. The electromagnetic brake according to claim 4, wherein: By controlling the direction and magnitude of the current flowing through the coil, the rotor can rotate.

6. The electromagnetic brake according to any one of claims 3 to 5, wherein: The rotor includes a plurality of the first elements.

7. The electromagnetic brake according to any one of claims 3 to 5, wherein: The stator includes a plurality of the second elements.

8. The electromagnetic brake according to any one of claims 3 to 5, wherein: The second element includes: a stator core that can be used as a part of the rotating electric machine; and the second permanent magnet embedded in a hole formed in the stator core by machining.

9. A rotating electric machine comprising an electromagnetic brake according to claim 5, wherein: The rotor is an inner rotor type and includes: a shaft; a first rotor core and a second rotor core, the first rotor core and the second rotor core being fixed to the shaft; and the first permanent magnet, the first permanent magnet being disposed between the first rotor core and the second rotor core in the direction of the shaft and being magnetized in the direction of the shaft, first rotor pole teeth are formed on an outer peripheral surface of the first rotor core at a predetermined pitch, second rotor pole teeth are formed on the outer peripheral surface of the second rotor core at a predetermined pitch, The first rotor pole teeth and the second rotor pole teeth are circumferentially offset from each other by half of the predetermined pitch, The stator includes a stator core, and the coil is wound around the stator core. The stator core includes stator pole teeth, and A magnetic circuit can be formed between the stator pole tooth and one of the first rotor pole tooth and the second rotor pole tooth facing the stator pole tooth, and The rotor is rotatable by a magnetic force generated between the stator pole teeth and one of the first rotor pole teeth and the second rotor pole teeth facing the stator pole teeth by energization of the coil.

10. A rotating electric machine comprising an electromagnetic brake according to claim 5, wherein: The rotor is an inner rotor type and includes a rotor core provided with at least one of the first permanent magnets and having an outer peripheral surface having a plurality of magnetic poles, the number of the plurality of magnetic poles being an integral multiple of 2 and the plurality of magnetic poles being equally spaced in the circumferential direction, The stator includes a stator core, and the coil is wound around the stator core. The stator core comprises stator pole teeth, A magnetic circuit can be formed between the stator pole teeth and a magnetic pole of the rotor core facing the stator pole teeth, and The rotor is rotatable by a magnetic force generated between the stator teeth and a magnetic pole of the rotor core facing the stator teeth by energization of the coil.

11. A rotating electric machine according to claim 9 or 10, wherein: The stator core includes: a yoke having a substantially annular shape surrounding the rotor; and first and second tooth portions protruding radially inward from an inner peripheral surface of the yoke so as to be separated from each other in the circumferential direction, The coil includes a first coil and a second coil respectively wound around the first tooth portion and the second tooth portion, and The second permanent magnet is arranged on the first tooth portion, separated outwardly from the distal end surface of the first tooth portion in the radial direction by a distance equal to or greater than the thickness of the second permanent magnet, and separated inwardly from the outer peripheral end surface of the yoke portion in the radial direction by a distance equal to or greater than the thickness of the second permanent magnet.

12. A rotating electric machine according to claim 11, wherein: The second permanent magnet is separated outwardly from the first coil in the radial direction.

13. A rotating electric machine according to claim 11, wherein: At least a portion of the second permanent magnet overlaps with the first coil.

14. A rotating electric machine according to claim 11, wherein: The second permanent magnet is separated inwardly from the first coil in the radial direction.

15. A rotating electrical machine according to any one of claims 12 to 14, wherein: When viewed in the direction of the axis, the second permanent magnet is disposed at a position overlapping with a center line passing through the first tooth portion and parallel to the radial direction, The width of the second permanent magnet in a direction perpendicular to the center line is greater than the thickness of the second permanent magnet in a direction parallel to the center line. One pole of the second permanent magnet faces radially inward, and The other magnetic pole of the second permanent magnet faces radially outward.

16. A rotating electric machine according to claim 9 or 10, wherein: The stator core includes: a yoke having a substantially annular shape surrounding the rotor; and first and second tooth portions protruding radially inward from an inner peripheral surface of the yoke so as to be separated from each other in the circumferential direction, The coil includes a first coil and a second coil respectively wound around the first tooth portion and the second tooth portion, The second permanent magnet is disposed on the yoke portion between the first tooth portion and the second tooth portion in the circumferential direction, One magnetic pole of the second permanent magnet faces one side in the circumferential direction, and The other magnetic pole of the second permanent magnet faces the other side in the circumferential direction.

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