JP2009273214A - Bearingless motor and artificial heart mounted with the bearingless motor, blood pump, artificial heart-lung machine, pump, fan, blower, compressor, actuator, reaction wheel, flywheel, and oscillating stage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearingless motor reduced in axial height and an artificial heart mounted with the bearingless motor, a blood pump, an artificial heart-lung machine, a pump, a fan, a blower, a compressor, an actuator, a reaction wheel, a flywheel, and an oscillating stage. <P>SOLUTION: An extremely-thin structure is achieved owing to an effect that a coil end is radially extended by applying a shaft supporting winding 161 and an electric-motor winding to a U-shaped stator core piece 150. An axial supporting force can be generated by the interference of the bias magnetic flux of permanent magnets 112A, 112B, 112C and 112D which pass through a clearance between the stator core piece 150 and stator cores 114, 124, the bias magnetic flux of a permanent magnet 130 and permanent magnets 122A, 122B, 122C and 122D, and the magnetic flux generated by the shaft supporting winding 161, thus achieving the bearingless motor. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bearingless motor and an artificial heart, blood pump, heart-lung machine, pump, fan, blower, compressor, actuator, reaction wheel, flywheel, swing stage equipped with the bearingless motor, The present invention relates to a bearingless motor that is shortened, and an artificial heart, blood pump, heart-lung machine, pump, fan, blower, compressor, actuator, reaction wheel, flywheel, and swing stage equipped with the bearingless motor.

  The bearingless motor is a motor that can rotate without contact while the main shaft is magnetically levitated (see, for example, Non-Patent Document 1). In general motors, the stator is provided with rotating windings (motor windings). However, in bearingless motors, magnetic levitation windings (shaft supporting windings) are additionally provided. ing.

  When a current is passed through this shaft support winding, a magnetic force acts in the radial direction of the rotor. By measuring the displacement of the rotor in the radial direction and adjusting this magnetic force, the two-degree-of-freedom motion of the rotor in the radial direction is actively controlled to enable non-contact magnetic levitation support.

  A simplified longitudinal sectional view of a general bearingless motor is shown in FIGS. The bearingless motor 10 of FIG. 14 is an inner rotor type in which the rotor 1 is disposed inside the stator 2. The iron core 3 of the stator 2 is circumferentially provided with a slot (not shown). The motor winding and the shaft support winding are wound around the slot, and the coil end 4 projects from the iron core 3 in the axial direction. ing.

  The bearingless motor 20 of FIG. 15 is an outer rotor type in which the rotor 21 is disposed outside the stator 22. The iron core 23 of the stator 22 is circumferentially provided with a slot (not shown). The motor winding and the shaft supporting winding are wound around the slot, and the coil end portion 24 projects from the iron core 23 in the axial direction. ing. These bearingless motors 10 and 20 actively control the two-degree-of-freedom motion in the radial direction, and the three degrees of freedom in the axial direction and the tilt direction are passively supported by the magnetic coupling.

  Conventionally, this two-degree-of-freedom control type bearingless motor has been reported (see, for example, Non-Patent Document 2 and Non-Patent Document 3). These bearingless motors are of the outer rotor type as shown in FIG. Conventionally, an inner rotor type bearingless motor having a structure different from that of FIG. 14 has also been reported (see, for example, Patent Document 1). A simplified longitudinal sectional view of the bearingless motor 30 is shown in FIG.

  In FIG. 16, the stator 32 has a cylindrical portion 32 b erected from the outer edge of the disc-shaped bottom portion 32 a, and a tooth portion 32 c is separated from the peripheral wall of the rotor 1 by a predetermined air gap at the upper end of the cylindrical portion 32 b. It protrudes horizontally toward the inside so as to face. A slot (not shown) is formed in the cylindrical portion 32b. An electric motor winding and a shaft supporting winding are wound around the slot, and the coil end portion 24 projects in the radial direction from the cylindrical portion 32b.

  Currently, the application of this two-degree-of-freedom control type bearingless motor to a centrifugal pump type auxiliary artificial heart is being studied. In this case, it is necessary to attach a blade to the upper side of the rotor and confine the integrated impeller in the pump chamber. Since the impeller rotates in a non-contact manner, there are merits such as being able to be driven permanently, no wear powder being mixed into blood, and suppression of blood coagulation due to frictional heat. At this time, it is necessary to consider the following two points.

  (1) In the case of the two-degree-of-freedom control type, if the height of the impeller is high, the difference between the center of the point of action of the force on the actuator and the position of the impeller center of gravity becomes large. In this case, if a force is applied in the translation direction, a moment is applied to the impeller and the impeller is inclined. As a result, since the magnetic levitation becomes unstable, it is necessary to design the impeller height as low as possible.

  (2) Since the auxiliary artificial heart is often implanted vertically in the patient's flank, the height of the auxiliary artificial heart needs to be designed to be low.

  In addition, a structure (Patent Document 2) in which a two-degree-of-freedom control type magnetic bearing and a direct drive type motor are combined has been reported. However, since the rotor is not a gear shape but a ring shape, it is not bearingless. Not applicable to motors.

A. Chiba et al., “Magnetic Bearings and Bearingless Drives”, published by Elsevier Newnes Press, 2005, p. 12-34 T. Masuzawa et al., `` Magnetically Suspended Centrifugal Blood Pump with a Self Bearing Motor '', ASAIO Journal, vol.48, pp.437-442, 2002. Yukiko Nakano et al., “Measurement of axial and conical characteristics of a bearingless motor with a U-shaped passive magnetic bearing”, 2007 IEEJ Industrial Application Conference, Young Engineer Poster Competition Proceedings, Y-127, 2006. Japanese Patent Application Laid-Open No. 2001-016687 “Electric Rotation Drive Device” JP-A-2005-121157 “Magnetic Bearing and Motor Device for Artificial Heart”

  By the way, in the bearingless motors 10 and 20 shown in FIGS. 14 and 15, the ends of the coils wound around the stators 3 and 23 spread in the axial direction. When the coil end portion extends in the axial direction, it is necessary to set the discharge port of the pump chamber to a higher position. It is necessary to set the blade position at a high position at the same time. The situation during this time will be described using the outer rotor type of FIG. 17 as an example. The height of the impeller 25 is increased by the height of the coil end portion 24, and the control may become unstable.

  In addition, when the bearingless motor shown in FIG. 16 is applied to a centrifugal pump type auxiliary artificial heart, the coil end portion 34 does not expand in the axial direction, while the partly disk-shaped bottom portion 32a and the cylindrical portion 32b of the stator 32 have blades. Since it is arranged under the car, there is a problem that the overall height becomes high.

  The present invention has been made in view of such a conventional problem, and a bearingless motor in which the height in the axial direction is shortened, or an artificial heart, blood pump, artificial heart lung, pump equipped with the bearingless motor, An object is to provide a fan, a blower, a compressor, an actuator, a reaction wheel, a flywheel, and a swing stage.

In order to solve the above-mentioned problems, the bearingless motor of the present invention (Claim 1) is configured such that a rotor and an inner circumference or an outer circumference of the rotor face each other with a predetermined air gap therebetween, and an upper stator tooth and a lower side A plurality of stator core pieces having stator teeth are arranged in the circumferential direction and are provided with a motor winding and / or a shaft support winding wound around the stator core pieces. To do.
The upper stator tooth and the lower stator tooth are arranged at a predetermined distance in the axial direction, and when an electric current is passed through the shaft support winding, the upper stator tooth and the lower stator tooth are excited to different poles. Also features.

  Thereby, it is possible to generate a support magnetic flux that passes through the rotor, the upper stator teeth, the stator core pieces, and the lower stator teeth.

  In the bearingless motor of the present invention (claim 2), the rotor includes an upper magnetic plate facing the upper stator tooth, a lower magnetic plate facing the lower stator tooth, A permanent magnet that is sandwiched between a side magnetic plate and the upper magnetic plate and is magnetized in the axial direction is provided.

  Furthermore, in the bearingless motor of the present invention (invention 3), the rotor is opposed to the upper stator teeth and has an upper magnetic plate having an upper permanent magnet magnetized in the radial direction, and the lower fixed And a lower magnetic plate having a lower permanent magnet that is magnetized in the radial direction so as to face the child teeth.

  Furthermore, in the bearingless motor of the present invention (Claim 4), the rotor is opposed to the upper stator teeth and has an upper magnetic plate having an upper permanent magnet magnetized in the radial direction, and the lower fixed A lower magnetic plate having a lower permanent magnet that is magnetized in the radial direction opposite to the slave teeth, and a permanent magnet that is sandwiched between the lower magnetic plate and the upper magnetic plate and is magnetized in the axial direction Configured.

  In the air gap portion of the bearingless motor of the present invention, the bias magnetic flux of the permanent magnet interferes with the support magnetic flux generated by the shaft support winding wound around the stator, and the magnetic flux density is reduced in the air gap portion. Unbalanced, magnetic force acts on the rotor. By measuring the radial displacement of the rotor and adjusting the magnetic force, the radial movement of the rotor can be actively controlled. Due to the magnetic coupling between the stator and the rotor formed by the bias magnetic flux of the permanent magnet, a restoring force and a restoring torque are automatically applied even if the rotor is displaced in the axial direction or rotated in the tilt direction. For this reason, it is not necessary to control the three degrees of freedom in the axial direction and the tilt direction of the rotor.

  Furthermore, in the bearingless motor of the present invention (Claim 5), the stator core piece for each phase so that the magnetomotive force distribution generated by the shaft support winding is a sinusoidal approximation around the rotor. One winding is wound and / or a plurality of windings are wound and / or the number of turns of the winding is adjusted.

  The magnetomotive force distribution when observed around the air gap portion becomes a distribution close to a sine wave, the angle error is reduced, and the levitation of the rotor is stabilized.

  Furthermore, in the bearingless motor of the present invention (Claim 6), the lower stator teeth are arranged to move by a predetermined angle in the rotation direction with respect to the upper stator teeth, or the upper magnetic plate protrudes. The salient poles or permanent magnets of the lower magnetic plate are arranged to move by a predetermined angle in the rotational direction with respect to the poles or permanent magnets, or the upper and lower stator teeth are continuously skewed. Alternatively, the upper and lower rotor salient poles are continuously skewed.

  As a result, torque fluctuations from moving from each magnetic pole to the adjacent magnetic pole are reduced, and generation of cogging torque can be suppressed.

  Furthermore, the bearingless motor of the present invention (invention 7) includes an upper annular core that connects the upper stator teeth and a lower annular core that connects the lower stator teeth.

  As a result, torque fluctuations from moving from each magnetic pole to the adjacent magnetic pole are reduced, and generation of cogging torque can be suppressed.

Furthermore, the bearingless motor of the present invention (invention 8) is characterized in that the stator core piece is provided with a winding that serves both as an electric motor and a shaft support.
In Claim 1-7, it is described that the motor winding and the support winding are wound separately on the stator core, but as one winding, the current component of the motor, the current component of the support winding May be supplied in a superimposed manner. That is, it is possible to configure a bearingless motor having a winding that serves both as an electric motor and a support.

Furthermore, the artificial heart, blood pump, heart-lung machine, pump, fan, blower, compressor, actuator, reaction wheel, flywheel, swing stage of the present invention (Claim 9) is any one of Claims 1-8. It was constructed with the bearingless motor described in 1.
As a result, an artificial heart with a reduced axial height can be obtained, and the burden on the patient can be reduced.

  The bearingless motor of the present invention includes an artificial heart, blood pump, heart-lung machine, pump, fan, blower, compressor, actuator, reaction wheel, flywheel, swing stage, pure water pump, chemical pump, non-contact It can also be applied to a rotary stage.

  As described above, according to the present invention, the coil wound around the stator core piece spreads in the radial direction, so that the height of the pump chamber can be minimized. Further, since the stator is not disposed below the impeller, the height of the bearingless motor can be reduced. As described above, an ultrathin auxiliary artificial heart can be realized. Specifically, the height of the auxiliary artificial heart reported so far is 30 to 35 mm, which can be reduced to about 30 to 50%.

  Hereinafter, embodiments of the present invention will be described. An exploded perspective view and an external perspective view of a disk-type bearingless motor according to an embodiment of the present invention are shown in FIGS. 1 and 2, respectively. In FIG. 1, the rotor 100 includes an annular permanent magnet 130 between an upper hollow disk 110 and a lower hollow disk 120. Depending on the application, it may not be hollow.

  Grooves 111 </ b> A, 111 </ b> B, 111 </ b> C, and 111 </ b> D are formed at four positions on the periphery of the magnetic core 114 of the upper hollow disk 110 at positions separated by 90 degrees around the center. Permanent magnets 112A, 112B, 112C, and 112D are disposed in the grooves 111A, 111B, 111C, and 111D, respectively, and a salient pole structure is formed between the grooves.

  In addition, the lower hollow disk 120 is configured to be aligned symmetrically with the upper hollow disk 110, and permanent magnets 122A, 122B, 122C, 122D are arranged in the grooves 121A, 121B, 121C, 121D of the magnetic core 124, respectively. The salient pole structure is formed between the grooves.

  The permanent magnets 112A, 112B, 112C, and 112D are magnetized in the radial direction (direction toward the center of the upper hollow disk 110) or in parallel (for example, parallel to the X axis or Y axis in FIG. 1), for example, the N pole It is configured to face inward. On the other hand, the permanent magnets 122A, 122B, 122C, 122D of the lower hollow disk 120 are also in the radial direction (direction toward the center of the lower hollow disk 120) or parallel (for example, with respect to the X axis or Y axis in FIG. 1). Is different from the upper hollow disk 110 in that the south pole faces inward.

  The annular permanent magnet 130 is magnetized in the axial direction so that the north pole faces upward. Depending on the application, it may be a cylinder, a rectangular parallelepiped, a polyhedron, or the like, without being annular. The magnetic core 114, the magnetic core 124, and the annular permanent magnet 130 are fixed by being attracted by a magnetic force, but may be fixed by an adhesive or the like. A through hole 140 is formed by a hole 113 formed in the center of the magnetic core 114, a hole 123 formed in the center of the magnetic core 124, and the annular permanent magnet 130. There may be no place to go and no stagnation for a long time.

  On the outer periphery of the rotor 100, twelve independent stator core pieces 150 are equally arranged in a circumferential shape. The number may not be equal, and the number may be an integer such as 3, 4, 5. At the upper end of the square core portion 150a of the stator core piece 150, the upper side expanded in a substantially trapezoidal or square wave shape toward the inside so as to face the peripheral wall of the upper hollow disk 110 with a predetermined air gap therebetween. Stator teeth 150b are projected.

  Similarly, at the lower end of the rectangular iron core portion 150a, it expands in a substantially trapezoidal shape toward the inside symmetrically with the upper stator teeth 150b so as to face the peripheral wall of the lower hollow disk 120 with a predetermined air gap therebetween. The lower stator teeth 150c thus formed are projected. An electric motor winding and a shaft support winding (not shown) are wound around the rectangular iron core portion 150a. However, the shaft support winding may be wound separately on the upper stator teeth 150b and the lower stator teeth 150c.

Next, the operation of the embodiment of the present invention will be described with reference to FIG.
3 shows a cross-sectional view taken along line AA in the plan view shown on the upper side. The annular permanent magnet 130 is magnetized with an N pole on the upper side and an S pole on the lower side in the figure.

  Further, the permanent magnets 112A, 112B, 112C, and 112D all have an S pole on the outside and an N pole on the inside. Similarly, the permanent magnets 122A, 122B, 122C, 122D are all magnetized with the N pole on the outside and the S pole on the inside. Due to the bias magnetic fluxes of all the permanent magnets described above, the outer side of the magnetic core 114 can be regarded as N-pole magnetization, and the outer side of the magnetic core 124 can be regarded as S-pole magnetization. Therefore, in the case of the present embodiment, the bearingless motor operates as an 8-pole motor by providing the stator core piece 150 with an 8-pole motor winding. Note that NS may be inverted.

  The direction of the bias magnetic flux acting on the air gap 163a and the air gap 163b between the rotor core and the stator core is indicated by solid arrows passing through the annular permanent magnet 130, the magnetic core 114, the stator core piece 150, and the magnetic core 124. As shown, it is bilaterally symmetric in the drawing.

  Here, when currents in directions shown in the figure are passed in opposite directions to the shaft support windings 161A and 161G wound around the stator core pieces 150A and 150G, between the stator core and the rotor core, A supporting magnetic flux is generated in the direction indicated by the dotted arrow through the magnetic core 114, the stator core piece 150A, the magnetic core 124, and the stator core piece 150G. Thereby, the magnetic flux density increases in the air gap 163a on the right side of the drawing, and decreases in the air gap 163b on the left side. The upper stator teeth 150b, the lower stator teeth 150c, and the magnetic cores 114 and 124 in the vicinity of the air gaps 163a and 163b are tapered so that the axial thickness gradually decreases as the air gaps 163a and 163b are approached. Also good. Furthermore, the shape of the stator core piece 150 may not be a U-shaped longitudinal section, but may be a C shape. Furthermore, the rectangular iron core portion 150a may not be a rectangular parallelepiped shape but may be a cylindrical shape.

  Due to this imbalance of magnetic flux density, a magnetic force acts on the rotor 100 on the right side. This magnetic force depends on the magnitude of the current. Therefore, the radial position of the rotor 100 is actively controlled by measuring the radial displacement of the rotor 100 and adjusting the amount of current. Even if the rotor 100 is displaced in the axial direction or rotated in the tilt direction, a restoring force and a restoring torque are automatically applied. For this reason, it is not necessary to control the three degrees of freedom in the axial direction and the tilt direction of the rotor 100. The same applies to the Y axis, which is the direction orthogonal to the line AA. As described above, the rotor 100 can be supported and rotated in a non-contact manner.

  Here, even if the permanent magnets 112A, 112B, 112C, 112D and the permanent magnets 122A, 122B, 122C, 122D are not provided, the principle of the induction machine and the homopolar machine works, so that the floating and rotation are possible. Further, even if the annular permanent magnet 130 is not provided, the bias magnetic flux similar to that shown in FIG. 3 is applied to the air gap 163a and the air gap 163b by the action of the permanent magnets 112A, 112B, 112C, and 112D and the permanent magnets 122A, 122B, 122C, and 122D. As a result, levitation and rotation are possible.

  The shaft support winding 161 is applied to the stator core piece 150 separately from the motor winding (not shown) so as to form two poles. When a three-phase inverter is used for controlling the shaft support winding 161, for example, a winding method as shown in FIG. In FIG. 4A, the shaft support winding 161 is wound so as to straddle two adjacent stator core pieces 150, and a U-phase is formed by a pair facing each other. Similarly, as shown in FIGS. 4B and 4C, a V-phase and a W-phase are formed, and the shaft support windings 161 are arranged so as to be shifted by 120 degrees.

  By the way, in a bearingless motor, a force may be actually generated in a direction deviated by a certain angle with respect to the X-axis direction even though a current is passed through the X-axis. When the rotation angle of the rotor is in an axially symmetric position, that is, when the rotation angle is a multiple of 45 degrees, the force generation direction coincides with the X axis direction, but at other angles, the force generation direction is the same. A difference occurs in the X-axis direction.

  It is desirable that the error angle formed by the force generation direction and the X axis is as small as possible in terms of the stability of magnetic levitation. In the case of the winding method of FIG. 4, the magnetomotive force distribution when observed around the air gap portion becomes a distribution close to a square wave, and the angle error becomes relatively large, which may cause a problem in levitation stability.

  In contrast, in FIG. 5, shaft support windings 163 </ b> A and 163 </ b> B having a smaller number of turns than the shaft support winding 161 are applied to the stator core pieces 150 on both sides of the shaft support winding 161. In this case, the magnetomotive force distribution when observed around the air gap portion is a distribution close to a sine wave. FIG. 6 shows a comparison of the error generation angle between the direction of force generation and the X axis with respect to the rotor angle due to the difference in winding method between FIGS. Accordingly, in the case of the winding method of FIG. 5, the maximum error angle is small and effective.

  In the present embodiment, the twelve stator core pieces 150 are disposed, but the present invention is not limited to this, and is not limited to this, but is 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, It may be an integer of 14 or more. In addition to the three-phase winding, a multi-phase AC winding such as a four-phase, five-phase, and six-phase winding may be configured. Although two poles of the shaft support winding have been described, 2n (n is a natural number) is possible. The rotor also has a consequent pole structure, but a permanent magnet surface pasting type, built-in type, hybrid type, homopolar type, comb type, transversal type, induction machine type, reluctance type, etc. can be applied.

  An example in which this embodiment is applied to an artificial heart is shown in FIG. As shown in FIG. 7, a blade 171 is attached to the upper surface of the rotor 100 to form an impeller, and this impeller is enclosed in a housing 173. A blood suction port 175 is provided at the center of the upper surface of the housing 173, while a blood discharge port 177 is disposed on the side of the blade 171. The stator core piece 150 is opposed to the rotor 100 with the housing 173 therebetween.

  In such a configuration, blood drawn from the blood inlet 175 is smoothly discharged from the blood outlet 177.

  Note that the bearingless motor of the present embodiment can also be applied to a non-contact rotary stage used in a clean environment such as in a vacuum chamber. Furthermore, although not shown in the drawings, the present invention can also be applied to a bearingless electromagnetic rotating machine capable of controlling multiple degrees of freedom by arranging a plurality of bearingless motors in the axial direction in a plurality of tandems.

  Further, when the rotor 1 is driven to rotate, vibrations in the rotational direction are generated by cogging torque caused by torque fluctuations and the like that occur in the process from moving from each magnetic pole to the adjacent magnetic pole. In order to suppress this cogging torque, as shown in FIGS. 8 and 9, a skew corresponding to a predetermined rotation angle may be applied between the upper and lower stator teeth of the stator core piece 180. FIG. 8 is a plan view of a skewed stator core piece, and FIG. 9 is a perspective configuration diagram of the stator core piece.

  In this case, an upper plate piece 180d that is bent in the L-shape toward the rotation direction protrudes from the upper end of the square iron core portion 180a of the stator core piece 180, and is further fixed to the upper stator from the upper plate piece 180d. The teeth 180b are bent in an L shape. The upper stator teeth 180b are provided so as to expand in a substantially trapezoidal shape toward the inside so as to face the peripheral wall of the upper hollow disk 110 with a predetermined air gap therebetween.

  Similarly, a lower plate piece 180e bent in an L-shape in the reverse rotation direction protrudes from the lower end of the rectangular iron core portion 180a, and the lower stator teeth 180c are further provided to the lower plate teeth 160c from the lower plate piece 160e. It is bent in a letter shape. The lower stator teeth 180c project so as to expand in a substantially trapezoidal shape toward the inside so as to face the peripheral wall of the lower hollow disk 120 with a predetermined air gap therebetween.

  An electric motor winding and a shaft support winding (not shown) are wound around the rectangular iron core portion 180a. As a result, torque fluctuations from moving from each magnetic pole to the adjacent magnetic pole are reduced, and generation of cogging torque can be suppressed.

On the other hand, as shown in FIGS. 10 and 11, the skew may be applied to the rotor side instead of being formed on the stator side. FIG. 10 shows a plan view of a skewed rotor core piece, and FIG. 11 shows a perspective configuration diagram of a bearingless motor including the rotor core piece. In this case, for example, the permanent magnets 122A, 122B, 122C, and 122D disposed on the lower hollow disk 120 are shifted from each other by 45 degrees with respect to the permanent magnets 112A, 112B, 112C, and 112D disposed on the upper hollow disk 110. ing. In addition to the case of skewing 45 degrees in this way, it is only necessary to skew at an appropriate angle such as several degrees.
It is not easy to greatly attenuate the cogging torque only by adjusting the angular positions of the upper and lower rotors and stators. Therefore, if the upper rotor itself is skewed, the cogging torque can be effectively reduced as in the case of a general electric motor. If a magnetic core is formed by laminating a plurality of thin silicon steel plates or the like, skewing can be performed almost continuously. Or if it comprises a powder core etc., it can skew continuously.
On the other hand, even in the case of a stator, if a plurality of thin silicon steel plates are similarly laminated, skew can be made almost continuously. Or if it comprises a powder core etc., it can skew continuously.
Such skew may be applied only to the upper stator and / or rotor, or both the upper and lower sides may be skewed.

  Another example for suppressing the generation of cogging torque is shown in FIGS. FIG. 12 is an exploded perspective view of the bearingless motor, and FIG. 13 is a perspective external view.

  12 and 13, the stator core pieces 150 have been described as independent from each other. However, the upper annular core 181 disposed on the outer periphery of the upper hollow disk 110 with a predetermined air gap therebetween, and the lower side A lower annular iron core 183 is provided on the outer periphery of the hollow disk 120 with a predetermined air gap therebetween, and twelve upper stator teeth 150b are attached to the upper annular iron core 181 and twelve of the lower annular iron core 183 are attached. The lower stator teeth 150c may be attached respectively.

Even in this case, the torque fluctuation until moving from each magnetic pole to the adjacent magnetic pole can be reduced, so that the generation of cogging torque can be effectively suppressed. In addition, you may fix to parts, such as the outer side or inner side of the square core part 150a, the upper surface of the upper stator tooth 150b, and the lower surface of the lower stator tooth 150c, using materials, such as a cyclic | annular iron core or nonmagnetic stainless steel.
Also, the rotor and stator of the present embodiment can be stacked in the axial direction to be multistaged.
In general, a bearingless motor has an advantage that the support side can be configured with a smaller power capacity by separately providing the motor winding and the support winding. However, in applications where the output is small, the current driver can be simplified by adjusting the current supplied to one coil rather than by applying it separately. Therefore, in the present invention, although not shown, if the component for generating the torque of the current to be supplied and the component for realizing the magnetic support are superimposed and flowed, the coil does not have to be wound separately.

  The bearingless motor of the present invention can be applied to a pure water pump, a chemical pump, a blower, a non-contact rotary stage, etc. in addition to an artificial heart. The blood pump and heart-lung machine are pumps that operate outside the patient's body during the operation, but can be configured as shown in FIG. It is also possible to transfer liquids other than blood, and the configuration shown in FIG. 7 or a modification thereof can be applied to general-purpose, special liquid, high-temperature and low-temperature pumps. If the shape of the impeller is modified, a gas such as air can be transported in addition to the liquid, and it can be applied to fans, blowers, and compressors. In addition, it can be used as an actuator or swing stage without an impeller or cover, and can be applied to a reaction wheel for controlling the attitude of an artificial satellite or the like.

1 is an exploded perspective view of a disk-type bearingless motor according to an embodiment of the present invention. External perspective view Magnetic flux diagram and shaft support force generation principle diagram of bearingless motor of the present invention Example showing how to wind a 2-pole shaft support winding An example of winding to make the magnetomotive force distribution close to a sine wave when observed around the air gap Comparison of bearing force direction and X-axis error angle due to differences in support winding structure Example of applying this embodiment to an artificial heart Top view of a skewed stator core piece Perspective configuration diagram of skewed stator core pieces Top view of a skewed rotor core piece Exploded perspective view of bearingless motor including skewed rotor core pieces Exploded perspective view of a bearingless motor with an annular core Same perspective view Cross section of a typical inner rotor type bearingless motor Cross section of a typical outer rotor type bearingless motor Cross-sectional configuration diagram of bearingless rotating machine in Patent Document 1 Sectional view when an outer rotor type bearingless motor is applied to an artificial heart

Explanation of symbols

100 Rotor 110 Upper hollow disk 111, 121 Groove 112, 122 Permanent magnet 113, 123 Hole 114, 124 Magnetic core 120 Lower hollow disk 130 Annular permanent magnet 140 Through hole 150, 180 Stator core pieces 150b, 180b Upper stator tooth
150c, 180c Lower stator teeth 161, 163 Shaft support windings 163a, 163b Air gap 171 Blade 173 Housing 175 Blood inlet 177 Blood outlet 181 Upper annular core 183 Lower annular core

Claims (9)

A rotor,
Facing the inner or outer periphery of the rotor across a predetermined air gap,
A plurality of stator core pieces each having an upper stator tooth and a lower stator tooth are divided in the circumferential direction.
A bearingless motor comprising an electric motor winding and / or a shaft support winding wound around the stator core piece. The rotor is an upper magnetic plate facing the upper stator teeth;
A lower magnetic plate facing the lower stator teeth;
2. The bearingless motor according to claim 1, further comprising a permanent magnet sandwiched between the lower magnetic plate and the upper magnetic plate and magnetized in the axial direction. The rotor is opposed to the upper stator teeth and has an upper magnetic plate having an upper permanent magnet magnetized in the radial direction;
The bearingless motor according to claim 1, further comprising a lower magnetic plate having a lower permanent magnet that is opposed to the lower stator teeth and is radially magnetized. The rotor is opposed to the upper stator teeth and has an upper magnetic plate having an upper permanent magnet magnetized in the radial direction;
A lower magnetic plate having a lower permanent magnet opposed to the lower stator teeth and radially magnetized;
2. The bearingless motor according to claim 1, further comprising a permanent magnet sandwiched between the lower magnetic plate and the upper magnetic plate and magnetized in the axial direction. Windings are wound around one of the stator core pieces for each phase so that the magnetomotive force distribution generated by the shaft support windings is a sinusoidal approximation around the rotor, and / or The bearingless motor according to any one of claims 1 to 4, wherein the winding is wound and / or the number of turns of the winding is adjusted. The lower stator teeth are arranged to move by a predetermined angle in the rotational direction with respect to the upper stator teeth, or the salient poles of the lower magnetic plate with respect to the salient poles of the upper magnetic plate or permanent magnets, or The permanent magnet has been moved by a predetermined angle in the rotational direction, or the upper and lower stator teeth are continuously skewed, or the upper and lower rotor salient poles are continuously skewed. The bearingless motor according to claim 3, wherein the bearingless motor is provided. The bearing according to claim 1, comprising an upper annular core that connects the upper stator teeth and a lower annular core that connects the lower stator teeth. Less motor. The bearingless motor according to any one of claims 1 to 7, wherein the stator core piece is provided with a winding that serves both as an electric motor and a shaft support. An artificial heart, a blood pump, an artificial heart lung, a pump, a fan, a blower, a compressor, an actuator, a reaction wheel, a flywheel, and an oscillating stage equipped with the bearingless motor according to claim 1.

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