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JP-7855297-B2 - Intravascular blood pump with multilayer air-core coil

JP7855297B2JP 7855297 B2JP7855297 B2JP 7855297B2JP-7855297-B2

Inventors

  • ワン ジンポ

Assignees

  • アビオメド インコーポレイテッド

Dates

Publication Date
20260508
Application Date
20241031
Priority Date
20190628

Claims (20)

  1. An intravascular blood pump for insertion into a patient's heart, A slender housing having a proximal end and a distal end, and a vertical axis , The housing comprises a slotless permanent magnet motor housed within the aforementioned housing, The motor has p pairs of magnetic poles and n phases, where p is an integer of 1 or more and n is an integer of 3 or more, and the motor comprises a stator that extends along the longitudinal axis of the housing and has 2np coils wound to form two coils per phase per pair of magnetic poles , The stator comprises an inner winding having np coils, where one coil for each phase is arranged next to a coil for a different phase in phase order for each pole pair, and the inner winding has an outer surface; and an outer winding having np coils, where the coils for each phase in the outer winding are circumferentially aligned with the coils of the inner winding having the same phase for each pole pair. An intravascular blood pump in which the in-phase coils of each pole pair are electrically connected such that the current flowing through the coils is in the same direction.
  2. The intravascular blood pump according to claim 1, wherein each coil of the inner winding and each coil of the outer winding comprises two magnet wire layers, each extending longitudinally along the length of the stator .
  3. The intravascular blood pump according to claim 2, wherein the magnet wires in each of the coils are arranged sequentially next to each other along the span of the coil.
  4. The intravascular blood pump according to claim 1 , wherein the inner winding of the coil establishes a uniform surface on which the outer winding of the coil is superimposed.
  5. The intravascular blood pump according to claim 1 , wherein one phase coil is electrically connected to the other phase coil in either a star configuration or a delta configuration.
  6. The intravascular blood pump according to claim 5, wherein in-phase coils are connected in either series or parallel.
  7. The intravascular blood pump according to claim 1 , wherein each of the 2np coils has a coil winding pattern selected from the group consisting of a helical winding pattern, a diamond winding pattern, and a hybrid winding pattern.
  8. The intravascular blood pump according to claim 1 , wherein the motor comprises a three-phase, one-pole pair machine.
  9. The intravascular blood pump according to claim 8 , wherein the motor comprises a six-coil, two-pole machine in which each coil extends at a mechanical angle of 120 degrees around the cross-section of the stator.
  10. A slotless permanent magnet electric motor having p pairs of magnetic poles and n phases, wherein p is an integer greater than or equal to 1 and n is an integer greater than or equal to 3, the motor has a vertical axis and extends along the vertical axis of the housing and has a stator having 2np coils wound to form two coils per phase per pair of magnetic poles, and an inner winding comprising np coils, one coil for each phase arranged in phase order for each pair of poles, adjacent to coils for different phases , the inner winding having an outer surface and; A slotless permanent magnet electric motor comprising an outer winding having np coils arranged on the outer surface of the inner winding , wherein the coils of each phase in the outer winding are circumferentially aligned with the coils of the inner winding having the same phase for each pole pair, and the coils of the same phase for each pole pair are electrically connected such that the current flowing through the coils is in the same direction.
  11. The slotless permanent magnet electric motor according to claim 10 , comprising two layers of magnet wire, each of the coils of the inner winding and each of the coils of the outer winding, each extending longitudinally along the length of the stator.
  12. The slotless permanent magnet electric motor according to claim 11 , wherein the magnet wires in each coil are arranged sequentially next to each other along the span of the coil.
  13. The slotless permanent magnet electric motor according to claim 10 , wherein the inner winding of the coil establishes a uniform base upon which the outer winding of the coil is superimposed.
  14. A slotless permanent magnet electric motor according to claim 10 , wherein one phase coil is electrically connected to the other phase coil in either a star configuration or a delta configuration.
  15. The slotless permanent magnet electric motor according to claim 14 , wherein two of the coils per phase are connected in either series or parallel.
  16. The slotless permanent magnet electric motor according to claim 10 , wherein each of the 2np coils has a coil winding pattern selected from the group consisting of a helical winding pattern, a diamond winding pattern, and a hybrid winding pattern.
  17. The slotless permanent magnet electric motor according to claim 16 , wherein the motor comprises a three-phase two-pole machine.
  18. The electric motor according to claim 16 , wherein the motor comprises a 6-coil, 2-pole machine, each coil extending at a mechanical angle of 120 degrees around the cross-section of the stator.
  19. A method for forming a stator for use in a slotless permanent magnet motor, The motor has p pairs of magnetic poles and n phases, where p is an integer greater than or equal to 1 and n is an integer greater than or equal to 3. The stator extends in the longitudinal direction and comprises 2np coils wound to form two coils per phase per pole pair, The method is A step of forming an inner winding comprising np coils, each having a phase order for each pole pair, with one coil for each phase arranged next to coils for different phases , wherein the inner winding has an outer surface; A method comprising the steps of: forming an outer winding comprising np coils arranged on the outer surface of the inner winding , wherein the coils of each phase in the outer winding are circumferentially aligned with the coils of the inner winding having the same phase for each pole pair; and electrically connecting the coils of the same phase for each pole pair so that current flows through the coils in the same direction.
  20. The method according to claim 19 , comprising the step of forming coils on an inner winding and an outer winding such that each coil comprises two layers of magnet wire extending longitudinally along the length of the stator.

Description

Cross-reference of related applications This application claims the benefit of U.S. Provisional Patent Application No. 62/868,530, filed on 28 June 2019 and incorporated herein by reference. Technical Field: This technology relates to an intravascular blood pump system comprising a permanent magnet motor and a stator having coils. background Intravascular blood pumps, such as the Impella® pump by Abiomed, Inc. of Danvers, MA, are rapidly becoming the current standard for ventricular assist devices. The Impella® pump series currently includes the Impella 2.5®, Impella 5.0®, Impella CP®, and Impella LD® pumps. These pumps are inserted percutaneously into the patient's body through a single access point (e.g., radial, femoral, or axillary access) via a small-diameter (6–7 Fr) catheter, allowing the pump head to be placed in the left ventricle of the patient's heart. The pump head comprises an electric motor containing a stator configured to magnetically interact with a rotor to rotate it, thereby providing a volumetric flow of blood through the rotor and into the patient's heart. Currently, Impella® pumps can deliver blood at flow rates of approximately 1.0 to 6.0 liters per minute (lpm). However, with the increasing use of Impella® in more and more surgical procedures, there is a growing demand for even higher blood flow rates beyond these levels. This essentially means that the rotor speed of the electric motor needs to be increased. However, due to the small geometry involved, increasing the rotor speed has several implications that can affect the operation of such small pumps. For example, increasing the rotor speed can lead to increased heat generation (Joule heating) within the electric motor. Since the device is inserted percutaneously into the heart, such increased heat generation can have serious consequences. Another point to consider is the resistive load placed on the device; modifications made to the electric motor to achieve higher flow rates can lead to higher resistive losses. Various techniques have been employed to increase the torque coefficient and/or efficiency of a motor, including increasing the number of turns and mounting density of the coils within the motor. However, such topologies are limited by constraints imposed on the motor, such as its size (e.g., diameter and/or length). This has led to the implementation of post-processing methods, such as mechanically squeezing the coils, to adhere to motor dimensional constraints; however, such methods compromise motor reliability, for example, by damaging the insulation of the wires forming the coils, leading to short circuits. Given the shortcomings of the current technological situation described above, there is a significant need to increase the flow rate generated by electric motors while maintaining or increasing the efficiency of the motors. Brief Overview This specification discloses a device to address various problems and shortcomings of the current state of technology described above. More specifically, an intravascular blood pump for insertion into a patient's heart is disclosed herein. The blood pump of the present invention comprises an elongated housing having a proximal end connected to a catheter and a distal end connected to a pump; the housing has a longitudinal axis. The blood pump comprises a slotless permanent magnet motor housed within the housing, the motor having p pairs of magnetic poles and n phases, where p is an integer greater than zero and n is an integer greater than or equal to 3. The motor comprises a stator extending along the longitudinal axis of the housing and having 2np coils wound to form two coils per phase per permanent pole pair. The stator comprises an inner winding having np coils, in which one coil for each phase is arranged next to a coil for a different phase in phase order for each pole pair, and this arrangement is repeated around the circumference of the stator for all pole pairs such that each coil of the inner winding spans a mechanical angle of 360/(np) degrees around the cross-section of the stator, and the inner winding has an outer surface. The stator also comprises an outer winding having np coils, arranged on the outer surface of the inner winding, and each coil of the outer winding is also arranged so that each coil of the outer winding spans a mechanical angle of 360/(np) degrees around the cross-section of the stator, and each coil of the outer winding is circumferentially aligned with the coils of the inner winding having the same phase for each pole pair. Within the stator, the coils of the same phase for each pole pair are connected such that the current flowing through the coils is in the same direction. The coil windings described herein are formed from magnet wire. Magnet wire is well known to those skilled in the art and will not be described in detail herein. In addition, the motor is equipped with a magnet that is supported to rotate when it magnetically interacts with