JP2012013043A - Rotary drive device and centrifugal pump device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary drive device that has high efficiency of energy, low cost and compact size.SOLUTION: This centrifugal blood pump device includes: an impeller 10 arranged in a blood chamber 7; a plurality of permanent magnets 17 arranged at the impeller 10; a plurality of sets of magnetic materials 18 which are arranged in a motor chamber 8, and rotatively drive the impeller 10 via a partition 6; and a coil 20. The magnetic materials 18 include band-shaped thin magnetic steel plates 18a which are wound around a center line L1 a plurality of times. By this arrangement, iron losses in the magnetic materials 18 can be reduced by a simple constitution.

Description

  The present invention relates to a rotary drive device and a centrifugal pump device using the rotary drive device, and more particularly to a rotary drive device that transmits a driving force through a partition wall and a centrifugal pump device using the rotary drive device.

  In recent years, a canned motor having a structure in which a motor drive chamber and a rotor chamber are separated by a partition wall is often used. Such a motor is used, for example, in a pump for transporting pure water in a semiconductor production line used in an environment where dust is not desired or a pump for transporting biological fluid. As a pump for transporting a biological fluid, there is a centrifugal blood pump device using a direct drive motor that directly transmits torque to an impeller in a blood chamber. This centrifugal blood pump device can be used as an artificial heart because it can eliminate physical communication between the outside and the blood chamber and can prevent bacteria and other blood from entering the blood. Since the artificial heart is driven by power from the battery, it is very important to improve the efficiency of the motor.

  The centrifugal blood pump of Patent Document 1 includes a housing including first to third chambers partitioned by first and second partition walls, and an impeller provided rotatably in the second chamber (blood chamber). A magnetic body provided on one surface of the impeller, an electromagnet provided in the first chamber facing the one surface of the impeller, a permanent magnet provided on the other surface of the impeller, and a third chamber A rotor and a motor provided, and a permanent magnet provided on the rotor facing the other surface of the impeller. A dynamic pressure groove is formed on the surface of the second partition wall facing the other surface of the impeller. Due to the attractive force acting on one side of the impeller from the electromagnet, the attractive force acting on the other surface of the impeller from the permanent magnet of the rotor, and the hydrodynamic bearing effect of the dynamic pressure groove, the impeller is separated from the inner wall of the second chamber, Rotates without contact.

  Further, the centrifugal blood pump of Patent Document 2 is rotatably provided in a housing including first to third chambers partitioned by first and second partition walls, and a second chamber (blood chamber). An impeller, a magnetic body provided on one surface of the impeller, a first permanent magnet provided in the first chamber facing the one surface of the impeller, and a second provided on the other surface of the impeller A permanent magnet, a rotor and a motor provided in a third chamber, and a third permanent magnet provided on the rotor so as to face the other surface of the impeller. A first dynamic pressure groove is formed on the surface of the first partition wall facing the one surface of the impeller, and a second dynamic pressure groove is formed on the surface of the second partition wall facing the other surface of the impeller. Yes. The attractive force acting on one surface of the impeller from the first permanent magnet, the attractive force acting on the other surface of the impeller from the third permanent magnet of the rotor, and the hydrodynamic bearing effect of the first and second dynamic pressure grooves Thus, the impeller is separated from the inner wall of the second chamber and rotates in a non-contact state.

  8 and 9 of Patent Document 3 includes a housing, an impeller provided rotatably in the housing, a first permanent magnet provided on one surface of the impeller, and an exterior of the housing. A rotor provided on the rotor, a second permanent magnet provided on the rotor facing the one surface of the impeller, a third permanent magnet provided on the other surface of the impeller, and a surface facing the other surface of the impeller And a magnetic body provided in the housing. A first dynamic pressure groove is formed on one surface of the impeller, and a second dynamic pressure groove is formed on the other surface of the impeller. Due to the attractive force acting on one side of the impeller from the second permanent magnet of the rotor, the attractive force acting on the other surface of the impeller from the magnetic body of the housing, and the hydrodynamic bearing effect of the first and second dynamic pressure grooves The impeller is separated from the inner wall of the housing and rotates in a non-contact state.

  Furthermore, the clean pump of Patent Document 4 includes a casing, an impeller provided rotatably in the casing, a first permanent magnet provided on one surface of the impeller, a rotor provided outside the casing, A second permanent magnet provided on the rotor facing one surface of the impeller, a magnetic body provided on the other surface of the impeller, and an electromagnet provided outside the housing facing the other surface of the impeller. ing. A dynamic pressure groove is formed on one surface of the impeller. When the rotational speed of the impeller is lower than the predetermined rotational speed, the electromagnet is operated, and when the rotational speed of the impeller exceeds the predetermined rotational speed, energization to the electromagnet is stopped. Due to the attractive force acting on one surface of the impeller from the second permanent magnet of the rotor and the hydrodynamic bearing effect of the hydrodynamic groove, the impeller is separated from the inner wall of the housing and rotates in a non-contact state.

JP 2004-209240 A JP 2006-167173 A JP-A-4-91396 Japanese Utility Model Publication No. 6-53790

  However, in a canned motor in which a partition is provided between the stator and the rotor, there is a problem that it is difficult to achieve high torque and high efficiency because the gap between the stator and the rotor becomes large. In particular, in the case of a small motor, the degree of freedom in design is low due to dimensional restrictions and the like, and since it is easily affected by local magnetic saturation, it is difficult to increase efficiency.

  In addition, the pumps of Patent Documents 1 to 4 support the impeller in the axial direction by a dynamic pressure groove formed in the opposed portion of the impeller and the housing, and the permanent magnet provided on the impeller and the permanent provided outside the housing. This is common in that the radial direction of the impeller is supported by the attractive force with the magnet.

  The support rigidity of the dynamic pressure groove is proportional to the rotation speed of the impeller. Therefore, in order for the impeller to rotate stably without contacting the housing even when a disturbance is applied to the pump, it is necessary to increase the normal rotation speed range of the pump and increase the rigidity of the impeller in the axial direction. However, in the pumps of Patent Documents 1 to 4, since the radial direction is supported by using the attractive force of the permanent magnet, the support rigidity is low, and there is a problem that the impeller cannot be rotated at high speed.

  As a method of increasing the rigidity in the radial direction, there is a method of increasing the attractive force between the permanent magnet in the impeller and the permanent magnet or the stator arranged outside the housing. However, when the suction force is increased, the negative rigidity value of the impeller in the axial direction increases (that is, if the impeller moves in the axial direction, the suction force increases as the impeller moves), and the impeller is supported by dynamic pressure. There is a problem that the performance and the suction force acting between the impeller and the housing are increased, making it difficult to smoothly drive the impeller. Further, when the negative stiffness value in the axial direction of the impeller is larger than the positive stiffness due to the dynamic pressure, there is a problem that stable rotation cannot be performed. When the radial direction is supported by a passive magnetic bearing using a permanent magnet, the rigidity in the radial direction is determined by the negative rigidity value in the axial direction. Therefore, it is difficult to improve the radial rigidity under the conditions for realizing stable rotation, and the impeller mass must not be increased in order to rotate the impeller without contacting the housing.

  In particular, as shown in FIG. 39 of Patent Document 2, when the impeller is rotated by the magnetic interaction of an external motor coil and a permanent magnet disposed on the impeller, the impeller as shown in FIG. 3 of Patent Document 2 is used. Since the starting torque is small compared with the case where the rotor is rotationally driven by a magnetic coupling between permanent magnets, it is difficult to smoothly drive the impeller. This is because the centrifugal blood pump is rotatably provided in the second chamber (blood chamber) with respect to the housing including the first to third chambers partitioned by the first and second partition walls. This is because a canned motor structure is used in which the impeller is rotated by a motor, and the motor gap is wide. Therefore, a large current is required to generate the starting torque. Improving motor efficiency is necessary for reducing current at startup and reducing power consumption during rated rotation, and is particularly important in the case of battery drive.

  In general, as a method for improving the efficiency of a motor, there is a method of reducing iron loss by forming an iron core by laminating magnetic steel plates. There is also a method of improving the coil space factor by devising the shape of the iron core. However, depending on the size and shape of the iron core, there is a problem that workability and productivity deteriorate and the cost increases.

  Therefore, a main object of the present invention is to provide an energy efficient, low cost, compact rotary drive device and a centrifugal pump device using the same.

  A rotary drive device according to the present invention includes a housing including first and second chambers partitioned by a partition, a rotor provided rotatably along the partition in the first chamber, and a second chamber. A rotary drive device including a drive unit that rotationally drives the rotor via a partition wall, the rotary drive device including a plurality of first permanent magnets provided in the rotor and arranged in a rotation direction of the rotor. . The drive unit is provided to face the plurality of first permanent magnets, each of which has a plurality of first magnetic bodies each having a strip-shaped magnetic steel sheet wound around the center line, and each of the plurality of first permanent magnets. And a plurality of coils wound around the first magnetic body and generating a rotating magnetic field.

  Preferably, the magnetic steel sheet is wound in a columnar shape, each first magnetic body is formed in a columnar shape, and end surfaces of the plurality of first magnetic bodies are provided to face the plurality of first permanent magnets, The coils are each wound so as to cover the entire side surfaces of the plurality of first magnetic bodies.

Preferably, the magnetic steel plate is an electromagnetic steel plate.
Preferably, the magnetic steel plate is made of an amorphous metal.

Preferably, the magnetic steel sheet is wound in a cylindrical shape.
Preferably, the magnetic steel sheet is wound in a prismatic shape.

Preferably, the magnetic steel sheet is fixed in a shape wound by welding.
Preferably, the magnetic steel sheet is fixed in a shape wound by resin impregnation.

  Preferably, the magnetic steel plate comprises a plurality of cylindrical members wound concentrically around the center line and arranged concentrically, and each first magnetic body is provided on one side of the center line. A notch for cutting each of the plurality of cylindrical members in a direction parallel to the center line is formed.

Preferably, each first magnetic body is annealed.
Preferably, each first magnetic body further has a rod-shaped second magnetic body, and the magnetic steel sheet is wound around the second magnetic body.

Preferably, the magnetic steel plate is fixed to the corresponding second magnetic body by welding.
Also preferably, the second magnetic body is longer than the width of the corresponding magnetic steel sheet, and both end portions of the second magnetic body protrude from the wound magnetic steel sheet.

  Preferably, each first magnetic body further includes a third magnetic body coupled to an end of the second magnetic body on the partition wall side, and the rotation driving device further includes a plurality of first magnetic bodies. A fourth magnetic body is provided in common with the magnetic body, and is coupled to an end opposite to the partition wall of the second magnetic body included in each of the plurality of first magnetic bodies.

  Preferably, the third magnetic body is formed with a first hole for fitting the end of the second magnetic body on the partition wall side, and the fourth magnetic body has a plurality of first holes. A plurality of second holes are formed corresponding to the magnetic bodies, and are fitted into the opposite ends of the partition walls of the second magnetic bodies included in the corresponding first magnetic bodies.

  Preferably, the fourth magnetic body includes a strip-shaped magnetic steel sheet wound a plurality of times around the center line.

Preferably, the magnetic steel plate is an electromagnetic steel plate.
Preferably, the partition wall is formed in a cylindrical shape, and the rotor and the drive unit are arranged with a gap in the radial direction of the rotor.

  Preferably, the partition wall is formed in a planar shape, and the rotor and the drive unit are disposed with a gap in the extending direction of the rotation center axis of the rotor.

  Moreover, the centrifugal pump device according to the present invention includes the rotation driving device, and the rotor is an impeller that sends liquid by centrifugal force during rotation.

  The centrifugal pump device according to the present invention is provided with a housing including first and second chambers partitioned by a partition wall, and is rotatably provided along the partition wall in the first chamber. A centrifugal pump device provided with an impeller that feeds liquid and a drive unit that is provided in a second chamber and rotationally drives the impeller via a partition wall, the first permanent magnet provided on one surface of the impeller And provided on the inner wall of the first chamber facing one surface of the impeller, provided on the other surface of the impeller, and a second permanent magnet for attracting the first permanent magnet, with a gap between each other in the rotation direction of the impeller. And a plurality of third permanent magnets arranged open. Each third permanent magnet is magnetized in the extending direction of the rotation center axis of the impeller, and the magnetic poles of the two adjacent third permanent magnets are different from each other. The driving unit is provided to face the plurality of third permanent magnets, each of which has a plurality of magnetic bodies each having a strip-shaped magnetic steel sheet wound around the center line, and each of the plurality of first permanent magnets. A plurality of coils provided corresponding to the magnetic body, each wound around the corresponding magnetic body and generating a rotating magnetic field. During rotation of the impeller, the first attractive force between the first and second permanent magnets and the second attractive force between the plurality of third permanent magnets and the plurality of magnetic bodies are the impeller in the first chamber. It is balanced at the approximate center of the movable range. A first dynamic pressure groove is formed on one surface of the impeller or the inner wall of the first chamber facing it, and a second dynamic pressure groove is formed on the other surface of the impeller or a partition wall facing it.

  Preferably, the liquid is blood and the centrifugal pump device is used to circulate blood.

  In the rotary drive device and the centrifugal pump device according to the present invention, since the magnetic body of the drive unit is formed of a wound belt-shaped magnetic steel plate, iron loss in the magnetic body can be reduced, and efficiency is improved. be able to. In addition, since the magnetic body can be easily formed, it is possible to reduce the size of the apparatus, reduce the cost, and improve the productivity.

It is a front view which shows the external appearance of the pump part of the centrifugal blood pump apparatus by Embodiment 1 of this invention. It is a side view of the pump part shown in FIG. It is the III-III sectional view taken on the line of FIG. It is the IV-IV sectional view taken on the line of FIG. It is sectional drawing which shows the state which removed the impeller from the IV-IV sectional view taken on the line of FIG. It is sectional drawing which shows the state which removed the impeller from the VI-VI sectional view taken on the line of FIG. It is the VII-VII sectional view taken on the line of FIG. It is a figure which shows the structure of the magnetic body shown in FIG. It is a time chart which illustrates the voltage applied to a plurality of coils shown in FIG. It is a figure for demonstrating the floating position of the impeller shown in FIG. It is another figure for demonstrating the floating position of the impeller shown in FIG. It is a block diagram which shows the structure of the controller which controls the pump part shown in FIGS. 13 is a time chart showing the operation of the controller shown in FIG. 5 is a diagram illustrating a modification example of the first embodiment. FIG. It is a figure which shows the other example of a change of Embodiment 1. FIG. FIG. 10 is a diagram showing still another modification example of the first embodiment. FIG. 10 is a diagram showing still another modification example of the first embodiment. FIG. 10 is a diagram showing still another modification example of the first embodiment. FIG. 10 is a diagram showing still another modification example of the first embodiment. FIG. 10 is a diagram showing still another modification example of the first embodiment. It is a figure which shows the structure of the axial gap type motor by Embodiment 2 of this invention. It is a figure which shows the structure of the magnetic body shown in FIG. It is a figure which shows the structure of the radial gap type motor by Embodiment 4 of this invention. It is a figure which shows the structure of the magnetic body shown in FIG.

[Embodiment 1]
1-7, the pump part 1 of the centrifugal blood pump apparatus according to the first embodiment includes a housing 2 formed of a nonmagnetic material. The housing 2 includes a columnar main body 3, a cylindrical blood inflow port 4 erected at the center of one end surface of the main body 3, and a cylindrical blood outflow provided on the outer peripheral surface of the main body 3. Port 5 is included. The blood outflow port 5 extends in the tangential direction of the outer peripheral surface of the main body 3.

  In the housing 2, as shown in FIG. 3, a blood chamber 7 and a motor chamber 8 partitioned by a partition wall 6 are provided. In the blood chamber 7, as shown in FIGS. 3 and 4, a disc-like impeller 10 having a through hole 10a in the center is rotatably provided. The impeller 10 includes two shrouds 11 and 12 each having a donut plate shape and a plurality of (for example, six) vanes 13 formed between the two shrouds 11 and 12. The shroud 11 is disposed on the blood inlet port 4 side, and the shroud 12 is disposed on the partition wall 6 side. The shrouds 11 and 12 and the vane 13 are made of a nonmagnetic material.

  A plurality (six in this case) of blood passages 14 partitioned by a plurality of vanes 13 are formed between the two shrouds 11 and 12. As shown in FIG. 4, the blood passage 14 communicates with the central through hole 10 a of the impeller 10, and starts from the through hole 10 a of the impeller 10 and extends so that the width gradually increases to the outer peripheral edge. In other words, the vane 13 is formed between two adjacent blood passages 14. In the first embodiment, the plurality of vanes 13 are provided at equiangular intervals and formed in the same shape. Therefore, the plurality of blood passages 14 are provided at equiangular intervals and are formed in the same shape.

  When the impeller 10 is driven to rotate, the blood flowing in from the blood inflow port 4 is sent from the through hole 10a to the outer periphery of the impeller 10 through the blood passage 14 by centrifugal force and flows out from the blood outflow port 5.

  A permanent magnet 15 is embedded in the shroud 11, and a permanent magnet 16 that attracts the permanent magnet 15 is embedded in the inner wall of the blood chamber 7 facing the shroud 11. The permanent magnets 15 and 16 are provided for attracting (in other words, energizing) the impeller 10 on the side opposite to the motor chamber 8, in other words, on the blood inflow port 4 side.

  Instead of providing the permanent magnets 15 and 16 on the inner walls of the shroud 11 and the blood chamber 7, respectively, a permanent magnet may be provided on one of the inner walls of the shroud 11 and the blood chamber 7, and a magnetic material may be provided on the other. Moreover, you may form shroud 11 itself with the permanent magnet 15 or a magnetic body. Further, as the magnetic material, either a soft magnetic material or a hard magnetic material may be used.

  Moreover, the permanent magnet 16 may be one or plural. When there is one permanent magnet 16, the permanent magnet 16 is formed in a ring shape. When there are a plurality of permanent magnets 16, the plurality of permanent magnets 16 are arranged along the same circle at equal angular intervals. The permanent magnet 15 is the same as the permanent magnet 16, and may be one or plural.

  Further, as shown in FIG. 4, a plurality of (for example, eight) permanent magnets 17 are embedded in the shroud 12. The plurality of permanent magnets 17 are arranged along the same circle at equal angular intervals so that adjacent magnetic poles are different from each other. In other words, the permanent magnets 17 with the N pole facing the motor chamber 8 side and the permanent magnets 17 with the S pole facing the motor chamber 8 side are alternately arranged along the same circle at equal angular intervals. .

  If the weight of the permanent magnet 17 is kept constant, the gap between the adjacent permanent magnets 17 and 17 is increased when the gap is provided between the adjacent permanent magnets 17 and 17 as shown in FIG. The magnetic flux density between the permanent magnets 17 and 17 is larger than when the permanent magnets 17 cannot be opened, and the magnetic field around the permanent magnets 17 becomes stronger. Therefore, in the first embodiment, the magnetic coupling force between the permanent magnet 17 of the impeller 10 and the magnetic body 18 and the coil 20 in the motor chamber 8 can be increased. Therefore, it is possible to increase the rotational torque of the impeller 10 while keeping the apparatus size small.

  As shown in FIG. 7, a plurality of (for example, nine) magnetic bodies 18 are provided in the motor chamber 8. The plurality of magnetic bodies 18 are arranged along the same circle at equal angular intervals so as to face the plurality of permanent magnets 17 of the impeller 10. The base ends of the plurality of magnetic bodies 18 are joined to one disk-shaped magnetic body 19. A coil 20 is wound around each magnetic body 18.

  Here, in the first embodiment, as shown in FIG. 8, each magnetic body 18 includes a strip-like thin magnetic steel plate 18 a wound around the center line L <b> 1 perpendicular to the partition wall 6. The strip-shaped magnetic steel plate 18 a is wound in the length direction, and the width direction thereof is directed to a direction perpendicular to the partition wall 6. The magnetic steel plate 18a may be an electromagnetic steel plate having non-directional or directional magnetic characteristics, or may be formed of an amorphous metal or an amorphous alloy. Alternatively, the end of the winding end of the magnetic steel plate 18a may be welded to the magnetic steel plate 18a itself to fix the wound magnetic steel plate 18a in a predetermined shape, or the entire magnetic steel plate 18a is impregnated with resin, The magnetic steel plate 18a wound by curing the resin may be fixed in a predetermined shape.

  Thus, by forming the magnetic body 18 with the thin belt-shaped magnetic steel sheet 18a wound, the iron loss in the magnetic body 18 can be reduced and the magnetic permeability of the magnetic flux in the magnetic body 18 can be increased. The energy efficiency in the rotational drive of the impeller 10 can be increased. In addition, since the magnetic body 18 can be easily formed, the apparatus can be reduced in size, cost, and productivity can be improved.

  The magnetic steel plate 18a may be wound in a cylindrical shape or may be wound in a prismatic shape such as a triangular prism. FIG. 8 shows a state in which the magnetic steel plate 18a is wound in a columnar shape around the center line L1. The circular end surface of the magnetic body 18 formed in a columnar shape (that is, the magnetic steel plate 18 a wound in a columnar shape) is disposed to face the impeller 10 through the partition wall 6. The coil 20 is wound so as to cover the entire outer peripheral surface (side surface) of the columnar magnetic body 18. When the magnetic steel plate 18a is wound in a cylindrical shape, the circumferential length of the coil 20 can be minimized, the copper loss generated in the coil 20 can be reduced, and the energy efficiency in the rotational drive of the impeller 10 can be reduced. Can be increased.

  It is also possible to wind the magnetic steel plate 18a around the center line L1 in a prismatic shape such as a triangular prism. In FIG. 7, the magnetic steel plate 18a is wound around the center line L1 in a triangular prism shape. Triangular end faces of the magnetic body 18 formed in a triangular column shape (that is, the magnetic steel plate 18 a wound in a triangular column shape) are arranged to face the impeller 10 through the partition wall 6. The coil 20 is wound so as to cover the entire side surface of the triangular prism-shaped magnetic body 18. In addition, a space for winding the coil 20 is evenly secured around the plurality of magnetic bodies 18, and the surfaces of the two adjacent magnetic bodies 18 facing each other are provided substantially in parallel. For this reason, a large space for the coil 20 can be secured, and the number of turns of the coil 20 can be increased. Accordingly, a large torque for rotating the impeller 10 can be generated. Moreover, the copper loss which generate | occur | produces in the coil 20 can be reduced, and the energy efficiency in the rotational drive of the impeller 10 can be improved.

  The outer surface surrounding the plurality of magnetic bodies 18 (in FIG. 7, the circle surrounding the outer periphery of the plurality of magnetic bodies 18) is the outer surface surrounding the plurality of permanent magnets 17 (the outer periphery of the plurality of magnetic bodies 17 in FIG. 4). The outer surface surrounding the plurality of magnetic bodies 18 may be larger than the outer surface surrounding the plurality of permanent magnets 17. Moreover, it is preferable that the magnetic body 18 is designed so that there is no magnetic saturation at the maximum rating of the pump 1 (the condition that the rotational driving torque of the impeller 10 is maximum).

  For example, a voltage is applied to the nine coils 20 by a 120-degree conduction method. That is, nine coils 20 are grouped by three. Voltages VU, VV, and VW as shown in FIG. 9 are applied to the first to third coils 20 of each group. A positive voltage is applied to the first coil 20 during a period of 0 to 120 degrees, 0 V is applied during a period of 120 to 180 degrees, a negative voltage is applied during a period of 180 to 300 degrees, and 300 to 360 degrees. 0V is applied during this period. Therefore, the front end surface (end surface on the impeller 10 side) of the magnetic body 18 around which the first coil 20 is wound becomes the N pole in the period of 0 to 120 degrees and becomes the S pole in the period of 180 to 300 degrees. . The phase of the voltage VV is 120 degrees behind the voltage VU, and the phase of the voltage VW is 120 degrees behind the voltage VV. Therefore, by applying the voltages VU, VV, and VW to the first to third coils 20 respectively, a rotating magnetic field can be formed, and attraction between the plurality of magnetic bodies 18 and the plurality of permanent magnets 17 of the impeller 10. The impeller 10 can be rotated by the force and the repulsive force.

  Here, when the impeller 10 rotates at the rated rotational speed, the attractive force between the permanent magnets 15 and 16 and the attractive force between the plurality of permanent magnets 17 and the plurality of magnetic bodies 18 are within the blood chamber 7. The impeller 10 is balanced near the approximate center of the movable range. For this reason, in any movable range of the impeller 10, the acting force due to the suction force to the impeller 10 is very small. As a result, the frictional resistance at the time of relative sliding between the impeller 10 and the housing 2 generated when the impeller 10 starts rotating can be reduced. Further, there is no damage (surface irregularities) on the inner wall of the impeller 10 and the housing 2 during relative sliding, and the impeller 10 easily floats from the housing 2 even when the dynamic pressure during low-speed rotation is small. It becomes the state of. Therefore, hemolysis / thrombus does not occur due to relative sliding between the impeller 10 and the housing 2, and thrombus does not occur due to slight surface damage (unevenness) that occurs during relative sliding.

  A plurality of dynamic pressure grooves 21 are formed on the surface of the partition wall 6 facing the shroud 12 of the impeller 10, and a plurality of dynamic pressure grooves 22 are formed on the inner wall of the blood chamber 7 facing the shroud 11. When the rotational speed of the impeller 10 exceeds a predetermined rotational speed, a dynamic pressure bearing effect is generated between each of the dynamic pressure grooves 21 and 22 and the impeller 10. As a result, a drag force is generated from each of the dynamic pressure grooves 21 and 22 against the impeller 10, and the impeller 10 rotates in a non-contact state in the blood chamber 7.

  More specifically, the plurality of dynamic pressure grooves 21 are formed in a size corresponding to the shroud 12 of the impeller 10, as shown in FIG. Each dynamic pressure groove 21 has one end on the periphery (circumference) of a circular portion slightly spaced from the center of the partition wall 6 and has a width up to the vicinity of the outer edge of the partition wall 6 in a spiral shape (in other words, curved). It extends to gradually spread. The plurality of dynamic pressure grooves 21 have substantially the same shape and are arranged at substantially the same interval. The dynamic pressure groove 21 is a recess, and the depth of the dynamic pressure groove 21 is preferably about 0.005 to 0.4 mm. The number of the dynamic pressure grooves 21 is preferably about 6 to 36.

  In FIG. 5, ten dynamic pressure grooves 21 are arranged at an equal angle with respect to the central axis of the impeller 10. Since the dynamic pressure groove 21 has a so-called inward spiral groove shape, when the impeller 10 rotates in the clockwise direction, the liquid pressure increases from the outer diameter portion to the inner diameter portion of the dynamic pressure groove 21. For this reason, a repulsive force is generated between the impeller 10 and the partition wall 6, and this becomes a dynamic pressure.

  Instead of providing the dynamic pressure groove 21 in the partition wall 6, the dynamic pressure groove 21 may be provided on the surface of the shroud 12 of the impeller 10.

  Thus, due to the hydrodynamic bearing effect formed between the impeller 10 and the plurality of hydrodynamic grooves 21, the impeller 10 is separated from the partition wall 6 and rotates in a non-contact state. For this reason, a blood flow path is ensured between the impeller 10 and the partition 6, and the blood retention between both and the generation | occurrence | production of the thrombus resulting from it are prevented. Furthermore, in the normal state, the dynamic pressure groove 21 exerts a stirring action between the impeller 10 and the partition wall 6, so that it is possible to prevent partial blood retention between the two.

  Further, the corner portion of the dynamic pressure groove 21 is preferably rounded so as to have an R of at least 0.05 mm. Thereby, generation | occurrence | production of hemolysis can be decreased more.

  Further, as shown in FIG. 6, the plurality of dynamic pressure grooves 22 are formed in a size corresponding to the shroud 11 of the impeller 10, similarly to the plurality of dynamic pressure grooves 21. Each dynamic pressure groove 22 has one end on the periphery (circumference) of a circular portion slightly spaced from the center of the inner wall of the blood chamber 7 and spirally (in other words, curved) on the inner wall of the blood chamber 7. It extends so that the width gradually increases to the vicinity of the outer edge. The plurality of dynamic pressure grooves 22 have substantially the same shape and are arranged at substantially the same interval. The dynamic pressure groove 22 is a recess, and the depth of the dynamic pressure groove 22 is preferably about 0.005 to 0.4 mm. The number of the dynamic pressure grooves 22 is preferably about 6 to 36. In FIG. 6, ten dynamic pressure grooves 22 are arranged at an equal angle with respect to the central axis of the impeller 10.

  The dynamic pressure groove 22 may be provided not on the inner wall side of the blood chamber 7 but on the surface of the shroud 11 of the impeller 10. Further, the corners of the dynamic pressure grooves 22 are preferably rounded so as to have an R of at least 0.05 mm. Thereby, generation | occurrence | production of hemolysis can be decreased more.

  Thus, due to the dynamic pressure bearing effect formed between the impeller 10 and the plurality of dynamic pressure grooves 22, the impeller 10 is separated from the inner wall of the blood chamber 7 and rotates in a non-contact state. Moreover, when the pump part 1 receives an external impact or when the dynamic pressure by the dynamic pressure groove 21 becomes excessive, it is possible to prevent the impeller 10 from sticking to the inner wall of the blood chamber 7. The dynamic pressure generated by the dynamic pressure groove 21 and the dynamic pressure generated by the dynamic pressure groove 22 may be different.

  It is preferable that the impeller 10 rotates in a state where the gap between the shroud 12 of the impeller 10 and the partition wall 6 and the gap between the shroud 11 of the impeller 10 and the inner wall of the blood chamber 7 are substantially the same. When disturbance such as fluid force acting on the impeller 10 is large and one gap is narrowed, the dynamic pressure by the dynamic pressure groove on the narrowing side is made larger than the dynamic pressure by the other dynamic pressure groove, To make the dynamic pressure grooves 21 and 22 different in shape.

  5 and 6, each of the dynamic pressure grooves 21 and 22 has an inward spiral groove shape, but the dynamic pressure grooves 21 and 22 having other shapes may be used. However, when blood is circulated, it is preferable to employ the inward spiral groove-shaped dynamic pressure grooves 21 and 22 that allow blood to flow smoothly.

  9 shows that the magnitude of the resultant force of the attractive force F1 between the permanent magnets 15 and 16 and the attractive force F2 between the permanent magnet 17 and the magnetic body 18 is other than the central position of the movable range in the blood chamber 7 of the impeller 10. It is a figure which shows the force which acts on the impeller 10 when it adjusts so that it may become zero in the position P1. However, the rotation speed of the impeller 10 is kept at the rated value.

  That is, the attraction force F1 between the permanent magnets 15 and 16 is set smaller than the attraction force F2 between the permanent magnet 17 and the magnetic body 18, and the floating position of the impeller 10 at which the resultant force becomes zero is from the middle of the impeller movable range. Is also on the partition wall 6 side. The shapes of the dynamic pressure grooves 21 and 22 are the same.

  The horizontal axis in FIG. 10 indicates the position of the impeller 10 (the left side in the figure is the partition wall 6 side), and the vertical axis indicates the acting force on the impeller 10. When the acting force on the impeller 10 acts on the partition wall 6 side, the acting force is negative. The acting force on the impeller 10 includes an attractive force F1 between the permanent magnets 15 and 16, an attractive force F2 between the permanent magnet 17 and the magnetic body 18, a dynamic pressure F3 in the dynamic pressure groove 21, and a dynamic force in the dynamic pressure groove 22. The pressure F4 and the resultant force “net force F5 acting on the impeller” are shown.

  As can be seen from FIG. 10, at the position where the net force F <b> 5 acting on the impeller 10 is zero, the floating position of the impeller 10 is greatly deviated from the center position of the movable range of the impeller 10. As a result, the distance between the rotating impeller 10 and the partition wall 6 is narrowed, and the impeller 10 contacts the partition wall 6 even if a small disturbance force acts on the impeller 10.

  On the other hand, FIG. 11 shows that the magnitude of the resultant force between the attractive force F1 between the permanent magnets 15 and 16 and the attractive force F2 between the permanent magnet 17 and the magnetic body 18 is the movable range in the blood chamber 7 of the impeller 10. It is a figure which shows the force which acts on the impeller 10 when it adjusts so that it may become zero in the center position P0. Also in this case, the rotational speed of the impeller 10 is kept at the rated value.

  That is, the attractive force F1 between the permanent magnets 15 and 16 and the attractive force F2 between the permanent magnet 17 and the magnetic body 18 are set to be substantially the same. Further, the shapes of the dynamic pressure grooves 21 and 22 are the same. In this case, the support rigidity with respect to the floating position of the impeller 10 is higher than in the case of FIG. Since the net force F5 acting on the impeller 10 is zero at the center of the movable range, the impeller 10 floats at the center position when no disturbance force acts on the impeller 10.

  Thus, the floating position of the impeller 10 is generated in the dynamic pressure grooves 21 and 22 when the impeller 10 rotates, and the attractive force F1 between the permanent magnets 15 and 16, the attractive force F2 between the permanent magnet 17 and the magnetic body 18, and the impeller 10. It is determined by the balance with dynamic pressures F3 and F4. By making F1 and F2 substantially the same and making the shape of the dynamic pressure grooves 21 and 22 the same, the impeller 10 can be floated at the substantially central portion of the blood chamber 7 when the impeller 10 rotates. As shown in FIGS. 3 and 4, the impeller 10 has a shape in which blades are formed between two disks. Therefore, two surfaces facing the inner wall of the housing 2 can have the same shape and the same size. Therefore, it is possible to provide the dynamic pressure grooves 21 and 22 having substantially the same dynamic pressure performance on both sides of the impeller 10.

  In this case, since the impeller 10 floats at the central position of the blood chamber 7, the impeller 10 is held at a position farthest from the inner wall of the housing 2. As a result, even if a disturbance force is applied to the impeller 10 when the impeller 10 is lifted and the floating position of the impeller 10 is changed, the possibility that the impeller 10 and the inner wall of the housing 2 are in contact with each other is reduced. The possibility of thrombus and hemolysis is also reduced.

  10 and 11, the two dynamic pressure grooves 21 and 22 have the same shape. However, the dynamic pressure grooves 21 and 22 have different shapes, and the dynamic pressure grooves 21 and 22 The pressure performance may be different. For example, when a disturbance in one direction always acts on the impeller 10 due to fluid force or the like during pumping, the performance of the dynamic pressure groove in the direction of the disturbance is made higher than the performance of the other dynamic pressure groove. Thus, the impeller 10 can be floated and rotated at the center position of the housing 2. As a result, the contact probability between the impeller 10 and the housing 2 can be kept low, and the stable flying performance of the impeller 10 can be obtained.

  The absolute value of the negative support rigidity value in the axial direction of the impeller 10 constituted by the attractive force F1 between the permanent magnets 15 and 16 and the attractive force F2 between the permanent magnet 17 and the magnetic body 18 is defined as Ka. If the absolute value of the radial positive stiffness value is Kr and the absolute value of the positive stiffness value obtained by the two dynamic pressure grooves 21 and 22 is Kg in the normal rotational speed region where the impeller 10 rotates, Kg> Ka + Kr It is preferable to satisfy the relationship.

  Specifically, when the absolute value Ka of the negative stiffness value in the axial direction is 20000 N / m and the absolute value Kr of the positive stiffness value in the radial direction is 10000 N / m, the rotation speed region where the impeller 10 normally rotates Thus, the absolute value Kg of the positive stiffness value obtained by the two dynamic pressure grooves 21 and 22 is set to a value exceeding 30000 N / m.

  Since the axial support rigidity of the impeller 10 is a value obtained by subtracting the negative rigidity due to the attractive force between the magnetic bodies from the rigidity caused by the dynamic pressure generated in the dynamic pressure grooves 21 and 22, it has a relationship of Kg> Ka + Kr. Thus, the support rigidity in the axial direction can be higher than the support rigidity in the radial direction of the impeller 10. By setting in this way, when a disturbance force acts on the impeller 10, the movement of the impeller 10 in the axial direction can be suppressed rather than the movement of the impeller 10 in the radial direction. The mechanical contact between the impeller 10 and the housing 2 can be avoided.

  In particular, since the dynamic pressure grooves 21 and 22 are recessed in a plane as shown in FIGS. 5 and 6, there is mechanical contact between the housing 2 and the impeller 10 at this portion during the rotation of the impeller 10. Then, scratches (unevenness on the surface) are generated on the surface of one or both of the impeller 10 and the inner wall of the housing 2, and if blood passes through this part, there is a possibility of causing thrombus and hemolysis. In order to prevent mechanical contact in the dynamic pressure grooves 21 and 22 and suppress thrombus and hemolysis, the effect of increasing the rigidity in the axial direction is higher than the rigidity in the radial direction.

  Further, when the impeller 10 is unbalanced, the impeller 10 swings during rotation. This swing is determined by the natural frequency determined by the mass of the impeller 10 and the support rigidity value of the impeller 10 and the rotational speed of the impeller 10. Maximum if matched.

In the pump unit 1, the support rigidity in the radial direction is smaller than the support rigidity in the axial direction of the impeller 10. Therefore, it is preferable to set the maximum rotational speed of the impeller 10 to be equal to or less than the natural frequency in the radial direction. Therefore, in order to prevent mechanical contact between the impeller 10 and the housing 2, the radial rigidity value of the impeller 10 constituted by the attractive force F1 between the permanent magnets 15 and 16 and the attractive force F2 between the permanent magnet 17 and the magnetic body 18 is set. When Kr (N / m), the mass of the impeller 10 is m (kg), and the rotational speed of the impeller is ω (rad / s), it is preferable that the relationship of ω <(Kr / m) ^0.5 is satisfied.

  Specifically, when the mass of the impeller 10 is 0.03 kg and the radial rigidity value is 2000 N / m, the maximum rotation speed of the impeller 10 is set to 258 rad / s (2465 rpm) or less. Conversely, when the maximum rotation speed of the impeller 10 is set to 366 rad / s (3500 rpm), the radial rigidity is set to 4018 N / m or more.

  Furthermore, it is preferable to set the maximum rotational speed of the impeller 10 to 80% or less of ω. Specifically, when the mass of the impeller 10 is 0.03 kg and the radial rigidity value is 2000 N / m, the maximum rotational speed is set to 206.4 rad / s (1971 rpm) or less. Conversely, when the maximum rotational speed of the impeller 10 is desired to be 366 rad / s (3500 rpm), the radial rigidity value is set to 6279 N / m or more. By setting the maximum rotation speed of the impeller 10 in this way, contact between the impeller 10 and the housing 2 during rotation of the impeller 10 can be suppressed.

  Further, the dynamic pressure grooves 21 and 22 have a negative rigidity value in the axial direction of the impeller 10 constituted by the attractive force F1 between the permanent magnets 15 and 16 and the attractive force F2 between the permanent magnet 17 and the magnetic body 18. When the rigidity due to the dynamic pressure increases, the impeller 10 and the housing 2 are not in contact with each other. Therefore, it is preferable to make this negative rigidity value as small as possible. Therefore, in order to keep the negative rigidity value small, it is preferable to make the sizes of the opposed surfaces of the permanent magnets 15 and 16 different. For example, by making the size of the permanent magnet 16 smaller than that of the permanent magnet 15, the rate of change of the attractive force that changes depending on the distance between them, that is, the negative stiffness can be kept small, and the impeller support stiffness is prevented from being lowered. Can do.

  Further, it is preferable that the impeller 10 is rotationally activated after confirming that the impeller 10 is in contact with the partition wall 6 before the impeller 10 is rotationally activated.

  That is, when the impeller 10 is not rotating, non-contact support by the dynamic pressure grooves 21 and 22 is not performed, and further, the attractive force F1 between the permanent magnets 15 and 16 and the attractive force F2 between the permanent magnet 17 and the magnetic body 18 are not. Therefore, the impeller 10 and the housing 2 are in contact with each other with a high surface pressure. When the impeller 10 is rotated by the magnetic interaction between the coil 20 and the magnetic body 18 in the motor chamber 8 and the permanent magnet 17 of the impeller 10 as in the pump unit 1, FIG. The starting torque is smaller than when the impeller as shown is rotated by a magnetic coupling between permanent magnets. Therefore, it is difficult to smoothly rotate and start the impeller 10.

  However, when the shroud 12 of the impeller 10 is in contact with the partition wall 6, compared with the case where the shroud 11 of the impeller 10 is in contact with the inner wall of the blood chamber 7, the permanent magnet 17 of the impeller 10 and the motor chamber 8 Since the magnetic body 18 is close, the rotational torque at the time of starting the impeller 10 can be increased, and the impeller 10 can be rotated and started smoothly.

  However, as described above, when the impeller 10 rotates, the attractive force F1 between the permanent magnets 15 and 16 and the attractive force F2 between the permanent magnet 17 and the magnetic body 18 are such that the position of the impeller 10 is within the movable range of the impeller 10. Since it is set so as to be balanced in the vicinity of the center, the impeller 10 is not necessarily in contact with the partition wall 6 when the impeller 10 is stopped.

  Therefore, this centrifugal blood pump device is provided with means for moving the impeller 10 toward the partition wall 6 before the impeller 10 is rotationally activated. Specifically, current is passed through the plurality of coils 20 so that the attractive force F2 between the permanent magnet 17 and the magnetic body 18 is increased, and the impeller 10 is moved to the partition wall 6 side.

  FIG. 12 is a block diagram illustrating a configuration of the controller 25 that controls the pump unit 1. In FIG. 12, the controller 25 includes a motor control circuit 26 and a power amplifier 27. The motor control circuit 26 outputs a three-phase control signal of, for example, a 120-degree energization method. The power amplifier 27 amplifies the three-phase control signal from the motor control circuit 26 and generates the three-phase voltages VU, VV, and VW shown in FIG. Three-phase voltages VU, VV, and VW are applied to first to third coils 20 described with reference to FIGS. Accordingly, during normal operation, the impeller 10 rotates at a predetermined rotational speed at the center position of the movable range.

  FIGS. 13A to 13C are time charts showing temporal changes in the coil current I, the position of the impeller 10 and the rotation speed of the impeller 10 when the impeller 10 starts rotating. 13A to 13C, in the initial state, the shroud 11 of the impeller 10 is in contact with the inner wall of the blood chamber 7, and the impeller 10 is at the position PA. A predetermined current I0 is passed through the coil 20 at time t0. Thereby, the attractive force F2 between the permanent magnet 17 and the magnetic body 18 becomes larger than the attractive force F1 between the permanent magnets 15 and 16, the impeller 10 moves to the position PB on the partition wall 6 side, and the shroud 12 of the impeller 10 is Contact the partition wall 6. When the impeller 10 moves to the position PB, the current I0 is cut off (time t1). It is preferable to provide a sensor for detecting the position of the impeller 10 in the blood chamber 7 and cut off the current I 0 after confirming that the impeller 10 has contacted the partition wall 6.

  Next, the coil current I is gradually increased to a predetermined rated value. At this time, since the impeller 10 is in contact with the partition wall 6, the impeller 10 rotates smoothly. As the coil current I increases, the impeller 10 moves from the position PB on the partition wall 6 side to the center position of the movable range.

  As described above, in the first embodiment, since the magnetic body 18 is formed by the wound belt-shaped thin magnetic steel plate 18a, the iron loss in the magnetic body 18 is reduced and the magnetic flux in the magnetic body 18 is reduced. The magnetic permeability can be increased, and the energy efficiency in the rotational drive of the impeller 10 can be increased. In addition, since the magnetic body 18 can be easily formed, the apparatus can be reduced in size, cost, and productivity can be improved.

  FIG. 14 is a block diagram showing a modification of the first embodiment. An example of a configuration for switching power supply at the time of impeller rotation activation and other cases is shown. 14, in this modification, the power amplifier 27 in FIG. 12 is replaced with power amplifiers 30 and 31 and a changeover switch 32. At time t <b> 0 to t <b> 1 in FIG. 13, the output signal of the motor control circuit 26 is supplied to the power amplifier 30, and the output voltage of the power amplifier 30 is applied to the coil 20 via the changeover switch 32. It is. After time t2, the output signal of the motor control circuit 26 is given to the power amplifier 31, the output voltage of the power amplifier 31 is applied to the coil 20 via the changeover switch 32, and a current flows through the coil 20.

  FIGS. 15A to 15C are time charts showing another modification of the first embodiment. 15A to 15C, in the initial state, the shroud 11 of the impeller 10 is in contact with the inner wall of the blood chamber 7, and the impeller 10 is at the position PA. A predetermined current I1 is passed through the coil 20 at time t0. For example, the motor control circuit 26 outputs a three-phase control signal of a 120-degree energization method. The power amplifier 27 amplifies the three-phase control signal from the motor control circuit 26 and generates the three-phase voltages VU, VV, and VW shown in FIG. The three-phase voltages VU, VV, and VW are applied to the first to third coils 20 described with reference to FIG. Therefore, a rotating magnetic field is applied to the impeller 10 by the current I1. This current I1 is larger than the current I0 in FIG. 13 and is a current that can rotate the impeller 10 even when the shroud 11 of the impeller 10 is in contact with the inner wall of the blood chamber 7. After the rotation start is confirmed, the coil current I is decreased and gradually increased to a predetermined rated value. In this way, even when the impeller 10 is on the position PA side, an excessive current may be supplied to the coil 20 only when the impeller 10 starts to rotate.

  In addition, a diamond-like carbon (DLC) film may be formed on at least one of the inner wall surface of the blood chamber 7 and the surface of the partition wall 6 and the surface of the impeller 10. Thereby, the frictional force between the impeller 10 and the inner wall of the blood chamber 7 and the partition wall 6 can be reduced, and the impeller can be rotated and started smoothly. In addition to the diamond-like carbon film, a fluorine resin film, a paraxylylene resin film, or the like may be formed.

  FIG. 16 is a cross-sectional view showing still another modified example of the first embodiment, and is a diagram to be compared with FIG. In FIG. 16, in this modified example, the sizes of the opposing surfaces of the opposing permanent magnets 15 and 16 are different. FIG. 3 shows a case where the sizes of the opposing surfaces of the permanent magnets 15 and 16 are the same. However, by varying the sizes of the opposing surfaces of the permanent magnets 15 and 16, the attraction changes depending on the distance between the two. The amount of change in force, that is, negative rigidity can be suppressed to a small value, and a decrease in the support rigidity of the impeller 10 can be prevented.

  FIG. 17 is a cross-sectional view showing still another modified example of the first embodiment, and is a view compared with FIG. In FIG. 17, in this modified example, a magnetic body 35 is provided on the tip surface of each magnetic body 18 facing the permanent magnet 17. The area of the surface of the magnetic body 35 facing the permanent magnet 17 is larger than the area of the tip surface of the magnetic body 18. In this modified example, the attractive force of the magnetic bodies 18 and 35 with respect to the permanent magnet 17 can be increased, and the energy efficiency in the rotational drive of the impeller 10 can be increased.

  FIG. 18 is a cross-sectional view showing still another modification of the first embodiment, and is a view compared with FIG. In FIG. 18, in this modified example, a notch 40 is formed from the inner peripheral surface to the outer peripheral surface of the magnetic body 18. That is, the magnetic steel plate 18a constitutes a plurality of cylindrical members that are wound around the center line L1 a plurality of times and arranged concentrically. The notch 40 cuts each of the plurality of cylindrical members in a direction parallel to the center line L1 on one side (right side in FIG. 18) of the center line L1. In this modified example, since the notch 40 is provided, the iron loss of the magnetic body 18 can be reduced.

  FIG. 19 is a cross-sectional view showing still another modified example of the first embodiment, and is a view compared with FIG. In FIG. 19, in this modified example, in the magnetic body 18, a rod-like magnetic body 41 that is a soft magnetic body is used as a core material. The magnetic steel plate 18 a is wound around the magnetic body 41 a plurality of times. By welding one end of the magnetic steel plate 18a to the magnetic body 41 and welding the other end of the magnetic steel plate 18a to the magnetic steel plate 18a itself, the magnetic steel plate 18a can be fixed in a predetermined shape. Alternatively, the entire magnetic body 41 and the magnetic steel plate 18a may be impregnated with resin, and the resin may be cured and fixed in a predetermined shape.

  FIG. 20 is a diagram showing still another modification of the first embodiment. In FIG. 20, in this modification, each magnetic body 18 includes a magnetic body 41, a magnetic steel plate 18 a, and a magnetic body 42. The length of the rod-shaped magnetic body 41 is longer than the width of the magnetic steel plate 18a. The magnetic steel plate 18a is wound around the central portion of the magnetic body 41, and both end portions of the magnetic body 41 protrude from the magnetic steel plate 18a wound in a columnar shape. The magnetic body 42 is formed in a fan shape, and a hole 42a is formed in the center thereof. One end portion (upper end portion in FIG. 20) of the magnetic body 41 is inserted into the hole 42 a of the magnetic body 42.

  The disk-shaped magnetic body 19 is formed with holes 19 a provided corresponding to the respective magnetic bodies 18. The other end (the lower end in FIG. 20) of the magnetic body 41 is inserted into the hole 19 a of the magnetic body 19. The magnetic body 42 is disposed on the partition wall 6 side. The magnetic body 42 is arranged with the center of the fan directed toward the center of the partition wall 6. The magnetic body 41 is fixed to each of the holes 42a and 19a by adhesion, press fitting, or shrink fitting. In this modified example, the magnetic body 18 can be easily assembled and fixed to the magnetic body 19 without using a positioning jig or the like, and workability is improved.

  Further, similarly to the magnetic body 18, the magnetic body 19 may be formed by winding a strip-shaped magnetic steel sheet a plurality of times around the center line.

[Embodiment 2]
FIG. 21A is a bottom view of the rotor 51 of the axial gap motor according to the second embodiment of the present invention as seen from the partition wall 50 side, and FIG. 21B is a front view showing the main part of the axial gap motor. FIG.

  21 (a) and 21 (b), this axial gap type motor has the same configuration as that of the pump unit 1 of the centrifugal blood pump apparatus according to the first embodiment, and is divided into a first partition and a first partition partitioned by a circular partition 50. 2 chambers (not shown). An annular rotor 51 provided rotatably along the partition wall 50 is provided in the first chamber, and a stator 60 that rotates the rotor 51 through the partition wall 50 is provided in the second chamber. ing.

  The rotor 51 includes an annular support member 52 formed of a nonmagnetic material, and a plurality of (for example, eight) permanent magnets 53 fixed to the support member 52. The plurality of permanent magnets 53 are arranged with a gap therebetween in the rotation direction of the rotor 51. Each permanent magnet 53 is magnetized in the extending direction of the rotation center axis of the rotor 51. The magnetic poles of two adjacent permanent magnets 53 are different from each other. The stator 60 includes a plurality of (for example, six) magnetic bodies 61 disposed to face the plurality of permanent magnets 53, and a plurality of coils 62 wound around the plurality of magnetic bodies 61 to generate a rotating magnetic field. Including. The plurality of magnetic bodies 61 are fixed to a disk-shaped magnetic body 63. The rotor 51 can be rotated by applying a voltage to the plurality of coils 62 by a 120-degree energization method.

  In the second embodiment, as shown in FIG. 22, each magnetic body 61 is formed by winding a strip-shaped magnetic steel plate 61 a a plurality of times around a center line perpendicular to the partition wall 50, similarly to the magnetic body 18 of the first embodiment. It is composed by turning. Further, the disk-shaped yoke 63 is configured by winding a belt-shaped magnetic steel plate 63a a plurality of times around a center line L2 perpendicular to the partition wall 50, as in the magnetic body 18 of the first embodiment. Yes.

  The magnetic steel plate 61a may be an electromagnetic steel plate having non-directional or directional magnetic characteristics, or may be formed of an amorphous metal or an amorphous alloy. Further, the end of the winding end of the magnetic steel plate 61a may be welded to the magnetic steel plate 61a itself to fix the magnetic steel plate 61a in a predetermined shape, or the entire magnetic steel plate 61a is impregnated with resin and the resin is cured. May be fixed in a predetermined shape. The magnetic steel plate 63a is the same as the magnetic steel plate 61a. Also in this second embodiment, the same effect as in the first embodiment can be obtained.

[Embodiment 3]
FIG. 23 is a plan view showing a main part of a radial gap type motor according to Embodiment 3 of the present invention.

  In FIG. 23, this radial gap type motor has the same configuration as the axial gap type motor of FIG. 21, and includes first and second chambers (not shown) partitioned by a cylindrical partition wall 70. A cylindrical rotor 71 that is rotatably provided along the partition wall 70 is provided in the first chamber inside the partition wall 70, and the rotor is interposed in the second chamber outside the partition wall 70 via the partition wall 70. A stator 80 that rotationally drives 71 is provided.

  The rotor 71 includes a cylindrical support member (not shown) formed of a nonmagnetic material, and a plurality of (for example, eight) permanent magnets 72 fixed to the support member. The plurality of permanent magnets 72 are arranged with a gap therebetween in the rotation direction of the rotor 71. Each permanent magnet 72 is magnetized in a direction (radial direction) orthogonal to the rotation direction of the rotor 71. The magnetic poles of two adjacent permanent magnets 72 are different from each other. The stator 80 includes a plurality of (for example, nine) magnetic bodies 81 disposed to face the plurality of permanent magnets 72, and a plurality of coils 82 wound around the plurality of magnetic bodies 81 and generating a rotating magnetic field. Including. The plurality of magnetic bodies 81 are fixed to the inner peripheral surface of the cylindrical magnetic body 83. The rotor 71 can be rotated by applying a voltage to the plurality of coils 82 by a 120-degree energization method.

  In the third embodiment, each magnetic body 81 is configured by winding a strip-shaped magnetic steel sheet a plurality of times around a center line perpendicular to the partition wall 50, similarly to the magnetic body 18 of the first embodiment. Yes. Further, as shown in FIG. 24, the cylindrical magnetic body 83 is configured by winding a strip-shaped magnetic steel plate 83a around the center line L3 of the partition wall a plurality of times.

  The magnetic steel plate 83a may be an electromagnetic steel plate having non-directional or directional magnetic characteristics, or may be formed of an amorphous metal or an amorphous alloy. Further, the end of the winding end of the magnetic steel plate 83a may be welded to the magnetic steel plate 83a itself to fix the magnetic steel plate 83a in a cylindrical shape, or the entire magnetic steel plate 83a is impregnated with resin and the resin is cured. It may be fixed in a cylindrical shape. In the third embodiment, the same effect as in the first embodiment can be obtained.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Pump part, 2 housing, 3 main-body part, 4 blood inflow port, 5 blood outflow port, 6,50,70 Septum, 7 blood chamber, 8 motor chamber, 10 impeller, 10a through-hole, 11,12 shroud, 13 vane , 14 Blood passage, 15-17, 53, 72 Permanent magnet, 18, 19, 28, 30, 35, 41, 42, 61, 63, 81, 83 Magnetic body, 18a, 61a, 63a, 83a Magnetic steel plate, 20 , 62, 82 Coil, 21, 22 Dynamic pressure groove, 25, 42 Controller, 26, 43 Motor control circuit, 27, 30, 31 Power amplifier, 32 selector switch.

Claims (22)

A housing including first and second chambers partitioned by a partition; a rotor provided rotatably along the partition in the first chamber; and a rotor provided in the second chamber via the partition. A rotary drive device comprising a drive unit for rotationally driving the rotor,
A plurality of first permanent magnets provided in the rotor and arranged in a rotation direction of the rotor;
The drive unit is
A plurality of first magnetic bodies each provided with a plurality of first permanent magnets, each having a strip-shaped magnetic steel sheet wound around a center line a plurality of times;
And a plurality of coils wound around the plurality of first magnetic bodies and generating a rotating magnetic field. The magnetic steel plate is wound in a columnar shape, and each first magnetic body is formed in a columnar shape,
The end surfaces of the plurality of first magnetic bodies are provided to face the plurality of first permanent magnets,
The rotary drive device according to claim 1, wherein each of the plurality of coils is wound so as to cover the entire side surface of each of the plurality of first magnetic bodies.   The rotary drive device according to claim 1, wherein the magnetic steel plate is an electromagnetic steel plate.   The rotary drive device according to claim 1, wherein the magnetic steel plate is made of an amorphous metal.   The rotation drive device according to any one of claims 1 to 4, wherein the magnetic steel plate is wound in a columnar shape.   The rotation drive device according to any one of claims 1 to 4, wherein the magnetic steel plate is wound in a prismatic shape.   The rotation drive device according to any one of claims 1 to 6, wherein the magnetic steel plate is fixed in a shape wound by welding.   The rotary drive device according to any one of claims 1 to 7, wherein the magnetic steel plate is fixed in a shape wound by resin impregnation. The magnetic steel plate comprises a plurality of cylindrical members wound concentrically around the center line and arranged concentrically,
Each of the first magnetic bodies has a cutout portion that cuts each of the plurality of cylindrical members in a direction parallel to the centerline on one side of the centerline. The rotational drive apparatus in any one of to.   The rotary drive device according to any one of claims 1 to 9, wherein each first magnetic body is annealed. Each first magnetic body further has a rod-shaped second magnetic body,
The rotation drive device according to any one of claims 1 to 10, wherein the magnetic steel plate is wound around the second magnetic body.   The rotation drive device according to claim 11, wherein the magnetic steel plate is fixed to a corresponding second magnetic body by welding. The second magnetic body is longer than the width of the corresponding magnetic steel sheet,
The both ends of the said 2nd magnetic body are the rotation drive devices of Claim 11 or Claim 12 which protrude from the said magnetic steel plate wound. Each first magnetic body further includes a third magnetic body coupled to an end of the second magnetic body on the partition wall side,
The rotary drive device is further provided in common with the plurality of first magnetic bodies, and an end portion of the second magnetic body included in each of the plurality of first magnetic bodies on the side opposite to the partition wall. The rotation drive device according to claim 13, further comprising a fourth magnetic body coupled to. The third magnetic body is formed with a first hole for fitting the end of the second magnetic body on the partition wall side,
The fourth magnetic body is provided corresponding to each of the plurality of first magnetic bodies, and an end portion of the second magnetic body included in the corresponding first magnetic body on the side opposite to the partition wall The rotation drive device according to claim 14, wherein a plurality of second holes for fitting the first and second holes are formed.   The rotary drive device according to claim 14 or 15, wherein the fourth magnetic body includes a strip-shaped magnetic steel plate wound a plurality of times around a center line.   The rotary drive device according to claim 16, wherein the magnetic steel plate is an electromagnetic steel plate. The partition is formed in a cylindrical shape,
The rotary drive device according to any one of claims 1 to 17, wherein the rotor and the drive unit are arranged with a gap in a radial direction of the rotor. The partition is formed in a planar shape,
The rotary drive device according to any one of claims 1 to 17, wherein the rotor and the drive unit are arranged with a gap in an extending direction of a rotation center axis of the rotor. A rotation drive device according to claim 19,
The rotor is a centrifugal pump device that is an impeller that sends liquid by centrifugal force during rotation. A housing including first and second chambers partitioned by a partition wall; an impeller which is rotatably provided along the partition wall in the first chamber and sends liquid by centrifugal force during rotation; and the second chamber A centrifugal pump device provided in a room and provided with a drive unit that rotationally drives the impeller through the partition wall,
A first permanent magnet provided on one surface of the impeller;
A second permanent magnet that is provided on an inner wall of the first chamber facing one surface of the impeller and attracts the first permanent magnet;
A plurality of third permanent magnets provided on the other surface of the impeller and arranged with a gap therebetween in the rotation direction of the impeller;
Each third permanent magnet is magnetized in the extending direction of the rotation center axis of the impeller,
The magnetic poles of each adjacent two third permanent magnets are different from each other,
The drive unit is
A plurality of magnetic bodies each provided with a plurality of third permanent magnets, each having a strip-shaped magnetic steel sheet wound around a center line a plurality of times;
A plurality of coils provided corresponding to the plurality of first magnetic bodies, each wound around a corresponding magnetic body, and generating a rotating magnetic field,
During the rotation of the impeller, the first attractive force between the first and second permanent magnets and the second attractive force between the plurality of third permanent magnets and the plurality of magnetic bodies are the first Balance in the middle of the movable range of the impeller in one room,
A first dynamic pressure groove is formed on one surface of the impeller or an inner wall of the first chamber facing the impeller, and a second dynamic pressure groove is formed on the other surface of the impeller or the partition wall facing the impeller. , Centrifugal pump device. The liquid is blood;
The centrifugal pump device according to claim 21, wherein the centrifugal pump device is used to circulate the blood.

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