Line knotting ring assembly, motor stator and motor

Abstract

The invention relates to the technical field of motors, aims to solve the technical problem of high cost caused by glue filling after glue coating of a knot wire ring group, and provides a knot wire ring assembly, a motor stator and a motor. The wire knotting ring assembly comprises an insulating frame and a plurality of wire knotting rings. The insulating frame comprises an insulating part. The insulating part is provided with a plurality of limiting parts. And the plurality of limiting parts are distributed along the rotating axis of the rotor of the motor. And each wire knotting ring is provided with a matching part. And the matching part of each wire knotting ring is propped against the limiting part of the insulating part, so that the plurality of wire knotting rings are fixed with the insulating frame along the axial direction of the rotating axis. The beneficial effects of the invention are that the assembly cost of the wire knotting ring and the motor stator can be reduced, the technological process of assembling the motor stator is simplified, and the assembly efficiency is improved.

Description

Technical Field

[0001] The present application relates to the field of motor technology, and in particular to a wire tie ring assembly, a motor stator and a motor. Background Art

[0002] In the related art, the assembly method between the wire tie ring and the motor stator is basically to assemble the prepared wire tie rings by injection molding (also known as overmolding) to obtain a wire tie ring group, and then position and weld the wire tie ring group and the stator to complete the assembly of the wire tie ring and the stator.

[0003] After the wire-binding ring group is fixed to the stator after the injection molding, the stator is generally potted with a potting glue to enhance the reliability of the motor. As far as the wire-binding ring group is concerned, the cost is relatively high if the glue is poured after the injection molding. Summary of the invention

[0004] In view of this, the present application provides a wire tie ring assembly, a motor stator and a motor, which effectively reduce the cost of encapsulating the wire tie ring assembly without affecting the assembly strength between the wire tie ring assembly and the stator.

[0005] An embodiment of the present application provides a wire tie ring assembly, which is arranged in the stator of a motor. The wire tie ring assembly includes an insulating frame and a plurality of wire tie rings. The insulating frame includes an insulating member. The insulating member is provided with a plurality of limit portions, and the plurality of limit portions are distributed along the rotation axis of the rotor of the motor. Each wire tie ring is provided with a mating portion. The mating portion of each wire tie ring abuts against the limit portion of the insulating member, so that the plurality of wire tie rings are fixed to the insulating frame along the axial direction of the rotation axis.

[0006] In the above embodiment, a mating portion is provided on each wire tie ring, and then a limiting portion is provided on the insulating member, and the mating portion and the limiting portion are abutted against each other to fix the wire tie ring on the insulating frame; further, a plurality of limiting portions are provided on the insulating member along the axial direction of the rotation axis, and the plurality of wire tie rings can be fixed on the insulating frame along the axial direction of the rotation axis. Compared with the existing method of assembling a plurality of wire tie rings into a wire tie ring group after injection molding and then welding them to the stator for fixing, this method can effectively save the cost of parts for injection molding of the wire tie ring group and the cost of the mold required for injection molding. At the same time, each wire tie ring and the insulating frame are assembled and fixed by the cooperation of the mating portion and the limiting portion, and there is no need to inject and demold the wire tie ring group, which simplifies the process flow of assembling the motor stator and improves the assembly efficiency.

[0007] In some embodiments of the present application, each limiting portion has a supporting surface, a first limiting surface, and a second limiting surface. The supporting surface is configured as an axial stopper ring along the rotation axis. The first limiting surface is configured as a circumferential stopper mating portion along the rotation axis. The second limiting surface is configured as a radial stopper mating portion along the rotation axis.

[0008] In the above embodiment, each limiting portion can realize axial limiting of the wire tie ring through the supporting surface, and each limiting portion also limits the wire tie ring circumferentially through the first limiting surface, and limits the wire tie ring radially through the second limiting surface; the limiting portion with such a structure enables the wire tie ring to be fixed to the insulating part, and then enables multiple wire tie rings to be fixed to the insulating frame in the axial direction of the rotation axis, completing the fixed connection between the wire tie ring group and the insulating frame, replacing the original fixed connection method that requires overmolding.

[0009] In some embodiments of the present application, a limiting protrusion is provided on the second limiting surface, and in the same limiting portion, the limiting protrusion is configured to limit the movement of the wire knot ring along the axial direction of the rotation axis in a direction away from the supporting surface.

[0010] In the above embodiment, a limiting protrusion is provided on the second limiting surface. In the same limiting part, the limiting protrusion stops the wire tie ring from escaping from the limiting part in the direction away from the supporting surface along the axial direction of the rotation axis. The limiting protrusion and the supporting surface are distributed on both sides of the axial direction of the wire tie ring, and the limiting protrusion and the supporting surface are used to limit the wire tie ring in two axial directions.

[0011] In some embodiments of the present application, each mating portion is provided with a first mating surface and a second mating surface. The first mating surface and the second mating surface are distributed on opposite sides of the limiting portion along the circumference of the rotation axis. And along the circumference of the rotation axis, there is a gap between the limiting portion and the first mating surface and / or between the limiting portion and the second mating surface.

[0012] In the above embodiment, along the circumferential direction of the rotation axis, the gap between the first mating surface and the limiting portion, and / or the gap between the second mating surface and , enables a clearance fit to be formed between the limiting portion and the matching portion in the circumferential direction of the rotation axis. In this way, when the wire tie ring is assembled with the insulating part, after completing the assembly of one limiting portion and the matching portion, the wire tie ring can be adjusted along the circumferential direction to facilitate the assembly of the other limiting portion and the matching portion, thereby facilitating the assembly.

[0013] In some embodiments of the present application, each mating portion is further provided with a third mating surface. Along the circumferential direction of the rotation axis, the first mating surface, the third mating surface and the second mating surface are sequentially connected. The limiting portion is configured to be able to produce elastic deformation. And along the radial direction of the rotation axis, the second limiting surface abuts the third mating surface and causes the limiting portion to elastically deform so as to apply an elastic force to the third mating surface.

[0014] In the above embodiment, when the limiting portion and the matching portion are assembled and connected, the second limiting surface abuts against the third matching surface and causes the limiting portion to deform. In this way, the matching portion can provide a radial force along the rotation axis to the limiting portion, so that the wire loop can be better fixed on the insulating frame under the action of elastic force.

[0015] In some embodiments of the present application, each mating portion is provided with a mating groove. A first mating surface, a third mating surface and a second mating surface are arranged to form a mating groove. Each mating groove accommodates a limiting portion.

[0016] In the above embodiment, the matching groove is a notch structure, and the limiting part is a protruding structure. Because the insulating frame is not only the main body that matches and connects with the wire tie ring, but also the winding body of the stator winding, it is necessary to ensure the overall structural strength of the insulating frame. If the limiting part is set to a notch structure, the structural strength of the insulating frame will be reduced; if the wire tie ring is set to a protruding structure, the material cost of the wire tie ring will increase. The wire tie ring is used to provide power connection to the motor, so it is only necessary to ensure that the wire tie ring is maintained at a lower current density to avoid local heating problems. In the circumferential direction along the axis of rotation, a matching groove is provided on the wire tie ring, and the limiting part corresponds to a protruding structure, and the limiting part abuts against the matching groove to fix the wire tie ring on the insulating frame. At the same time, from the perspective of assembly convenience, the protruding structure is provided on the insulating frame, and the wire tie ring only needs to move axially along the axis of rotation X so that the limiting part is inserted into the matching groove.

[0017] In some embodiments of the present application, the wire loop has a first side and a second side disposed opposite to each other, and the support surface supports the first side. Along the axial direction of the rotation axis, the distance between the support surfaces of two adjacent limit portions is greater than the distance between the first side and the second side of the same wire loop, so that the multiple wire loops are electrically insulated from each other.

[0018] In the above embodiment, when multiple tie rings are fixed to the insulating frame along the axial direction of the rotation axis, a sufficient spacing distance should be reserved between adjacent tie rings so that the multiple tie rings are electrically insulated from each other to prevent short circuits between different lines. The minimum spacing distance should be the minimum insulation distance of the motor under the working voltage. Of course, other insulation measures will be provided on the tie rings, such as using other non-conductive materials to separate the tie rings, or covering the surface of the tie rings with an insulating film layer, so the spacing distance can also provide a certain space for setting insulation measures.

[0019] In some embodiments of the present application, a plurality of wire-binding rings are stacked and installed on the insulating frame in sequence along the axial direction of the rotation axis. Along the stacking direction of the plurality of wire-binding rings, the projection of one limiting portion of the insulating member covers the projection of an adjacent limiting portion.

[0020] In the above embodiment, the multiple limiting portions of the insulating member are in a stepped structure; during assembly, each wire loop only needs to be moved to the corresponding limiting portion in sequence along the axis of the rotation axis; since the projection of a limiting portion of the insulating member will cover the projection of the adjacent limiting portion along the stacking direction of the multiple wire loops, the distance between the first mating surface and the second mating surface of the same mating portion on each wire loop will also be adjusted accordingly, and the distance between the first mating surface and the second mating surface of the same mating portion of the wire loop located on the upper layer will be smaller than that of the lower layer, so that the wrong position of the wire loop in the axial direction along the rotation axis can be effectively avoided.

[0021] In some embodiments of the present application, the insulating member includes an insulating body, a first frame and a second frame. The first frame and the second frame are arranged on the insulating body. Along the radial direction of the rotation axis, the first frame and the second frame of the insulating member are spaced apart to form a winding space for accommodating the stator winding. And the first frame of the insulating member is closer to the rotation axis than the second frame. The first frame is provided with a limiting portion. The first frame has a guide surface. The guide surface is located on a side of the first frame away from the second frame. A plurality of wire tie rings are stacked and installed on the insulating frame in sequence along the axial direction of the rotation axis. Along the stacking direction of the plurality of wire tie rings, the guide surface gradually moves away from the rotation axis.

[0022] In the above embodiment, a winding space for accommodating the stator winding is formed between the first frame and the second frame of the insulating member. When the stator winding is wound on the insulating body, each stator winding will generate tension, and each limiting portion on the insulating frame is arranged at a radially inner position along the rotation axis. The tension generated by the stator winding or the horizontal component of the tension will cause the limiting portion to deform radially inward, further interfering with the installation of the motor rotor. Therefore, a guide surface is provided on the side of the first frame close to the rotation axis, and the guide surface is gradually moved away from the rotation axis along the stacking direction of the multiple wire loops, that is, it becomes an inclined surface. The slope of the guide surface can be used to offset the radial deformation displacement of the limiting portion, thereby reducing the risk of the limiting portion interfering with the installation of the rotor.

[0023] In some embodiments of the present application, the first frame is further provided with a connecting portion. A winding space is provided between the connecting portion and the second frame. The guide surface includes a first facet and a second facet. The first facet is provided at the limiting portion. The second facet is provided at the connecting portion. Along the stacking direction of the plurality of wire loops, the projection of the first facet is further away from the rotation axis than the projection of the second facet.

[0024] In the above embodiment, since the stator winding occupies a certain winding space along the axial direction of the rotation axis when it is wound on the insulating body, in order to avoid interference between the stator winding and the wire tie ring in the axial direction, a connecting portion is further provided on the first frame, and the guide surface is provided as the first facet and the second facet on the limiting portion and the connecting portion respectively, so that the guide surface is formed into a structure in which two sections of inclined surfaces are connected, and along the stacking direction of the plurality of wire tie rings, the projection of the first facet is farther away from the rotation axis than the projection of the second facet, and the angle of deviation of the first facet from the rotation axis is greater than that of the second facet. Since the area on the first frame that is far away from the winding space is more affected by the tension generated by the stator winding, the angle of deviation of the second facet on the connecting portion close to the winding space from the rotation axis is smaller than that of the first facet, so as to ensure the structural strength of the connecting portion.

[0025] In some embodiments of the present application, the plurality of tie rings include a three-phase tie ring and a neutral point tie ring. The three-phase tie ring is provided with a circumferential annular extension around the axis of rotation, and the angle of the annular extension of the three-phase tie ring is less than 360°. Along the circumference of the axis of rotation, the three-phase tie ring is provided with a plurality of electrical welding points. The plurality of electrical welding points are arranged at intervals in the three-phase tie ring. The neutral point tie ring is provided with a circumferential annular extension around the axis of rotation, and the angle of the annular extension of the neutral point tie ring is equal to 360°. Along the circumference of the axis of rotation, the neutral point tie ring is provided with a plurality of grounding welding points, and the plurality of grounding welding points are arranged at intervals in the neutral point tie ring.

[0026] In the above embodiment, since in a three-phase motor, the stator windings are arranged according to a certain rule to ensure that the generated magnetic field is balanced and uniform. Therefore, on each three-phase tie ring, the electrical welding points electrically connected to the stator windings are arranged evenly spaced along the circumference, and of course, the grounding welding points on the neutral point connection ring are also arranged evenly spaced along the circumference. The stator winding of each phase needs to be grounded, so the neutral point tie ring is a full circle structure. For a single-phase three-phase tie ring, the ring segment between two adjacent electrical welding points is the location where the stator windings of other phases are electrically connected. Therefore, the ring segment between any two adjacent electrical welding points is removed, and the annular extension angle of the three-phase tie ring is designed to be less than 360°, which does not affect the transmission current of the three-phase tie ring to achieve material saving, and will not affect the assembly and fixation between each tie ring and the insulating frame. At the same time, the three-phase wiring ring is designed to be a non-circular structure, and the material can be overlapped in the mold design, so that it can be arranged more closely, and more three-phase wiring rings can be produced, further reducing material costs.

[0027] In some embodiments of the present application, there are multiple insulating members. The multiple insulating members are distributed in a ring around the rotation axis. Each wire tie ring is provided with multiple matching parts. Each matching part of a wire tie ring abuts against a limiting part of an insulating member.

[0028] In the above embodiment, multiple insulating parts are distributed in a ring around the rotation axis to form the entire insulating frame, and multiple matching parts on the wire tie ring are also distributed on the wire tie ring along the circumference of the rotation axis. The multiple matching parts on each wire tie ring are all abutted against a limiting part, thereby improving the fixing strength between the wire tie ring and the insulating frame.

[0029] An embodiment of the present application provides a motor stator. The motor stator includes a stator core, a stator winding and a wire tie ring assembly. There are multiple stator cores, multiple stator windings, and an insulating frame including multiple insulating members. Each insulating member is sleeved on a stator core. Each stator winding is wound on an insulating member. Each stator winding is connected to a wire tie ring.

[0030] In the above embodiments, each wire tie ring is fixed to the insulating frame by assembling a matching portion and a limiting portion, which ensures the current transmission function of the wire tie ring itself while ensuring the structural strength of the wire tie ring fixed in the motor stator, saving the material cost of the wire tie ring and simplifying the assembly steps.

[0031] An embodiment of the present application provides a motor, which includes a motor rotor and a motor housing, and also includes a motor stator, wherein the motor stator and the motor rotor are coaxially arranged in the motor housing.

[0032] In the above embodiment, the connection method between the motor stator and multiple tie rings in the motor is no longer to encapsulate the multiple tie rings and then weld them to the insulating frame, but to assemble the matching part of the tie rings and the limiting part of the insulating part, which reduces the assembly cost of the motor.

[0033] One embodiment of the present application provides a method for assembling a motor stator, which is used to assemble a motor housing and a motor stator. The assembly method includes: assembling a stator core, a stator winding and an insulating member into a stator structure. A plurality of wire tie rings are sequentially assembled with a plurality of stator structures along the axial direction of the rotation axis of the motor rotor, and the plurality of stator structures are annularly distributed around the rotation axis and fixed with a plurality of wire tie rings. The stator winding of each stator structure is welded to the corresponding wire tie ring to obtain a motor stator. The motor stator is installed into the motor housing and encapsulated by glue filling.

[0034] In the above embodiment, based on the connection structure between each tie ring and the insulating frame, multiple tie rings are directly assembled and connected with multiple stator structures in sequence along the axial direction of the rotation axis, so that multiple tie rings and the insulating frame are fixedly connected, and the connection strength is reliable. Each tie ring is no longer overmolded, which simplifies the assembly steps and saves material costs. After the motor stator is assembled, it is encapsulated in the motor housing by glue filling. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope.

[0036] Figure 1 A schematic diagram of the structure of a wire tie ring assembly provided in one embodiment of the present application; Figure 2 It is a schematic diagram of a partial structure of an insulating member in one embodiment of the present application; Figure 3 for Figure 2 A structural diagram from another perspective; Figure 4 for Figure 1 Enlarged view of point A in the middle; Figure 5 This is a schematic diagram of the structure of a three-phase wiring loop in one embodiment of the present application; Figure 6 for Figure 5 Enlarged view of point B in the middle; Figure 7 A schematic diagram of the structure of an insulating member provided in one embodiment of the present application; Figure 8 for Figure 7 Middle CC section view; Fig. 9 This is a schematic diagram of the structure of a neutral point tie line ring in one embodiment of the present application; Fig.10 A schematic structural diagram of a single-block stator structure provided in one embodiment of the present application; Fig.11 A schematic diagram of the assembly direction of a motor stator provided in an embodiment of the present application; Fig.12 A schematic flow chart of a method for assembling a motor stator according to an embodiment of the present application.

[0037] Description of main component symbols: 100, wire tie ring assembly; 1, insulating frame; 11, insulating member; 110, winding space; 111, insulating body; 112, first frame; 1120, guide surface; 1121, limit portion; 112a, support surface; 112b, first limit surface; 112c, second limit surface; 112d, limit protrusion; 112e, first facet; 1122, connecting portion; 112f, second facet; 113, second frame; 2, wire tie ring; 201, first side ; 202, second side; 21, mating part; 210, mating groove; 21a, first mating surface; 21b, second mating surface; 21c, third mating surface; 31, three-phase connection ring; 311, electrical welding point; 3101, U-phase connection ring; 3102, V-phase connection ring; 3103, W-phase connection ring; 32, neutral point connection ring; 321, grounding welding point; 200, stator structure; 4, stator core; 5, motor housing; H, spacing distance; X, rotation axis. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0040] Herein, the terms “first”, “second”, etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0041] It should be noted that when an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be a central element at the same time. When an element is considered to be "disposed on" another element, it may be directly disposed on the other element or there may be a central element at the same time.

[0042] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0043] The embodiment of the present application provides a wire tie ring assembly, which is arranged in the stator of the motor. The wire tie ring assembly includes an insulating frame and a plurality of wire tie rings. The insulating frame includes an insulating member. The insulating member is provided with a plurality of limit portions, and the plurality of limit portions are distributed along the rotation axis of the rotor of the motor. Each wire tie ring is provided with a mating portion. The mating portion of each wire tie ring abuts against the limit portion of the insulating member, so that the plurality of wire tie rings are fixed to the insulating frame along the axial direction of the rotation axis.

[0044] A matching portion is provided on each wire-binding ring, and then a limiting portion is provided on the insulating member. The matching portion and the limiting portion are abutted against each other to fix the wire-binding ring on the insulating frame. Further, a plurality of limiting portions are provided on the insulating member along the axial direction of the rotation axis, so that the plurality of wire-binding rings can be fixed on the insulating frame along the axial direction of the rotation axis. Compared with the existing method of assembling a plurality of wire-binding rings into a wire-binding ring group after injection molding and then welding the same to the stator for fixing, this method can effectively save the cost of parts for injection molding of the wire-binding ring group and the cost of the mold required for injection molding. At the same time, each wire-binding ring is assembled and fixed to the insulating frame through the cooperation between the matching portion and the limiting portion, and there is no need to inject and demold the wire-binding ring group, which simplifies the process flow of assembling the motor stator and improves the assembly efficiency.

[0045] Some embodiments of the present application are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0046] See also Figure 1 and Figure 4 , an embodiment of the present application provides a wire tie ring assembly 100, which is arranged in the stator of the motor. The wire tie ring assembly 100 includes an insulating frame 1 and a plurality of wire tie rings 2. The insulating frame 1 includes at least one insulating member 11. The insulating member 11 is provided with a plurality of limiting portions 1121, and the plurality of limiting portions 1121 are distributed along the rotation axis X of the rotor of the motor. Each wire tie ring 2 is provided with a mating portion 21. The mating portion 21 of each wire tie ring 2 abuts against the limiting portion 1121 of at least one insulating member 11, so that along the axial direction of the rotation axis X, the plurality of wire tie rings 2 are fixed to the insulating frame 1.

[0047] A matching portion 21 is provided on each wire tie ring 2, and then a limiting portion 1121 is provided on the insulating member 11. The matching portion 21 and the limiting portion 1121 are abutted against each other to fix the wire tie ring 2 on the insulating frame 1. Further, a plurality of limiting portions 1121 are provided on the insulating member 11 along the axial direction of the rotation axis X, so that the plurality of wire tie rings 2 can be fixed on the insulating frame 1 along the axial direction of the rotation axis X. Compared with the existing method of assembling a plurality of wire tie rings 2 into a wire tie ring group after injection molding and then welding them to the stator for fixing, this method can effectively save the cost of parts for injection molding of the wire tie ring group and the cost of the mold required for injection molding. At the same time, each wire tie ring 2 and the insulating frame 1 are assembled and fixed by the matching portion 21 and the limiting portion 1121, and there is no need to inject and demold the wire tie ring group, which simplifies the process flow of assembling the motor stator and improves the assembly efficiency.

[0048] See also Figure 2 and Figure 3In some embodiments, each limiting portion 1121 has a supporting surface 112a, a first limiting surface 112b, and a second limiting surface 112c. The supporting surface 112a is configured as an axial stopper for the knotting ring 2 along the rotation axis X. The first limiting surface 112b is configured as a circumferential stopper for the matching portion 21 along the rotation axis X. The second limiting surface 112c is configured as a radial stopper for the matching portion 21 along the rotation axis X.

[0049] Each limiting portion 1121 can realize axial limiting of the wire tie ring 2 through the supporting surface 112a, and each limiting portion 1121 also limits the wire tie ring 2 circumferentially through the first limiting surface 112b, and limits the wire tie ring 2 radially through the second limiting surface 112c; through the limiting portion 1121 with such a structure, the wire tie ring 2 can be fixed to the insulating member 11, and then in the axial direction of the rotation axis X, multiple wire tie rings 2 are fixed to the insulating frame 1, completing the fixed connection between the wire tie ring group and the insulating frame 1, replacing the original fixed connection method that requires overmolding.

[0050] See also Figure 3 In some embodiments, a limiting protrusion 112d is provided on the second limiting surface 112c, and the limiting protrusion 112d and the supporting surface 112a are distributed on both axial sides of the wire loop 2. The limiting protrusion 112d is configured to limit the movement of the wire loop 2 along the axial direction of the rotation axis X toward the direction away from the supporting surface 112a of the same limiting portion 1121.

[0051] In addition to the support surface 112a, the first limiting surface 112b and the second limiting surface 112c limiting the matching portion 21, a limiting protrusion 112d is further provided on the second limiting surface 112c, and the limiting protrusion 112d and the support surface 112a are used to limit the connection ring 2 in two axial directions, thereby improving the connection strength between the limiting portion 1121 and the matching portion 21. Figure 3 In the illustrated embodiment, along the axial direction of the rotation axis X, in the same limiting portion 1121, the side of the limiting protrusion 112d close to the supporting surface 112a is designed as an inclined surface for easy transition connection, which is beneficial for the matching portion 21 of the wire loop 2 to slide in along the axial direction of the rotation axis X, so that the first side 201 of the wire loop 2 abuts against the supporting surface 112a; the side of the limiting protrusion 112d close to the supporting surface 112a is designed to have an arc shape with a convex structure, which can better limit the wire loop 2 between the supporting surface 112a and the limiting protrusion 112d, and is beneficial for preventing the wire loop 2 from escaping along the axial direction of the rotation axis X.

[0052] See also Figure 4In some embodiments, each mating portion 21 is provided with a first mating surface 21a and a second mating surface 21b. The first mating surface 21a and the second mating surface 21b are distributed on opposite sides of the limiting portion 1121 along the circumferential direction of the rotation axis X. And along the circumferential direction of the rotation axis X, there is a gap between the limiting portion 1121 and the first mating surface 21a and / or between the limiting portion 1121 and the second mating surface 21b.

[0053] Along the circumferential direction of the rotation axis X, the gap between the first mating surface 21a and the limiting portion 1121, and / or the gap between the second mating surface 21b and 21, enables a clearance fit to be formed between the limiting portion 1121 and the mating portion 21 in the circumferential direction of the rotation axis X. In this way, when the wiring loop 2 is assembled with the insulating part 11, after completing the assembly of one limiting portion 1121 and the mating portion 21, the wiring loop 2 can be adjusted along the circumferential direction to facilitate the assembly of the other limiting portion 1121 and the mating portion 21, thereby facilitating the assembly.

[0054] See also Figure 5 and Figure 6 In some embodiments, each mating portion 21 is further provided with a third mating surface 21c. Along the circumferential direction of the rotation axis X, the first mating surface 21a, the third mating surface 21c and the second mating surface 21b are connected in sequence. The limiting portion 1121 is configured to be able to generate elastic deformation. And along the radial direction of the rotation axis X, the second limiting surface 112c abuts against the third mating surface 21c and causes the limiting portion 1121 to elastically deform so as to apply an elastic force to the third mating surface 21c.

[0055] When the limiting portion 1121 is assembled and connected with the matching portion 21, the second limiting surface 112c abuts against the third matching surface 21c and causes the limiting portion 1121 to deform, so that the matching portion 21 can provide a force along the radial direction of the rotation axis X to the limiting portion 1121, so that the wire tie ring 2 can be better fixed on the insulating frame 1 under the action of the elastic force. During implementation, the third matching surface 21c is closer to the rotation axis than the second limiting surface 112c, so that along the radial direction of the rotation axis X, interference is generated between the matching portion 21 and the limiting portion 1121, and the wire tie ring 2 can also be better stuck on the insulating frame 1.

[0056] In some embodiments, each mating portion 21 is provided with a mating groove 210. A first mating surface 21a, a third mating surface 21c and a second mating surface 21b are arranged to form a mating groove 210. Each mating groove 210 accommodates a limiting portion 1121.

[0057] In some embodiments, the matching groove 210 is a notch structure, and the limiting portion 1121 is a protruding structure. Because the insulating frame 1 is not only the main body that is matched and connected with the wire tie ring 2, but also the winding body of the stator winding, it is necessary to ensure the overall structural strength of the insulating frame 1. If the limiting portion 1121 is set to a notch structure, the structural strength of the insulating frame 1 will be reduced; if the wire tie ring 2 is set to a protruding structure, the material cost (copper amount) of the wire tie ring 2 will be increased. The wire tie ring 2 is used to provide power connection to the motor, so it is only necessary to ensure that the wire tie ring 2 is maintained at a lower current density to avoid local heating problems. In the circumferential direction along the rotation axis X, a matching groove 210 is opened on the wire tie ring 2, and the limiting portion 1121 is correspondingly a protruding structure. The limiting portion 1121 abuts against the matching groove 210 to fix the wire tie ring 2 on the insulating frame 1. At the same time, from the perspective of assembly convenience, the protruding structure is arranged on the insulating frame 1 , and the wire tie ring 2 only needs to move axially along the rotation axis X so that the limiting portion 1121 is inserted into the matching groove 210 .

[0058] See also Figure 6 In some embodiments, the first mating surface 21a and the second mating surface 21b in the mating groove 210 are arranged in parallel, and the third mating surface 21c is perpendicular to the first mating surface 21a and the second mating surface 21b, respectively, so that the mating groove 210 is constructed as a rectangular groove, and the third mating surface 21c is configured as the long side of the rectangle, and the first mating surface 21a and the second mating surface 21b are configured as the short sides of the rectangle.

[0059] The advantage of such a rectangular groove structure design is that, along the radial direction of the rotation axis X, based on the preset width of the wire tie ring 2, the first mating surface 21a and the second mating surface 21b are configured as short sides, so that the local current density of the ring segment where the mating portion 21 on the wire tie ring 2 is located will not be too large. If, in order to keep the current density within the preset range, the first mating surface 21a and the second mating surface 21b are configured as long sides, it is necessary to increase the width of the wire tie ring 2 radially outward along the rotation axis X, which increases the material cost. Therefore, the length value of the first mating surface 21a and the second mating surface 21b in the radial direction of the rotation axis X should not exceed half of the radial width of the wire tie ring 2. The third mating surface 21c can also be an arc shape, or multiple surfaces can be connected in sequence, so that the entire mating groove 210 is a polygonal groove; configuring the third mating surface 21c as the long side of the rectangular groove can save space in the radial direction of the wire tie ring 2, which is conducive to preventing the opening of the mating groove 210 from causing the local current density of the wire tie ring 2 to increase.

[0060] See also Figure 4In some embodiments, the wire loop 2 has a first side 201 and a second side 202 that are disposed opposite to each other, and the support surface 112a supports the first side 201. Along the axial direction of the rotation axis X, the distance between the support surfaces 112a of two adjacent limiting portions 1121 is greater than the distance between the first side 201 and the second side 202 of the same wire loop 2, so that the multiple wire loops 2 are electrically insulated from each other.

[0061] When multiple tie loops 2 are fixed to the insulating frame 1 along the axial direction of the rotation axis X, a sufficient spacing distance H should be reserved between adjacent tie loops 2 so that the multiple tie loops 2 are electrically insulated from each other to prevent short circuits between different lines. This spacing distance H should be at least the minimum insulation distance of the motor under the working voltage. Of course, other insulation measures will be provided on the tie loops 2, such as using other non-conductive materials to separate the tie loops 2, or covering the surface of the tie loops 2 with a film layer having insulating properties, so the spacing distance H can also provide a certain space for setting insulation measures.

[0062] Please continue to see Figure 4 In some embodiments, a plurality of wire loops 2 are sequentially stacked and installed on the insulating frame 1 along the axial direction of the rotation axis X. Along the stacking direction of the plurality of wire loops 2 , the projection of one limiting portion 1121 of the insulating member 11 covers the projection of an adjacent limiting portion 1121 .

[0063] The multiple limiting portions 1121 of the insulating member 11 have a stepped structure; during assembly, it is only necessary to move each wire loop 2 along the axis of the rotation axis X to the corresponding limiting portion 1121 in sequence; since along the stacking direction of the multiple wire loops 2, the projection of a limiting portion 1121 of the insulating member 11 will cover the projection of the adjacent limiting portion 1121, the distance between the first mating surface 21a and the second mating surface 21b of the same mating portion 21 on each wire loop 2 will also be adjusted accordingly, and the distance between the first mating surface 21a and the second mating surface 21b of the same mating portion 21 of the wire loop 2 located on the upper layer will be smaller than that of the lower layer, so that the position of the wire loop 2 in the axial direction along the rotation axis X can be effectively avoided.

[0064] See also Figure 7 and Figure 8In some embodiments, the insulating member 11 includes an insulating body 111, a first frame 112 and a second frame 113. The first frame 112 and the second frame 113 are arranged on the insulating body 111. Along the radial direction of the rotation axis X, the first frame 112 and the second frame 113 of the insulating member 11 are arranged at intervals to form a winding space 110 for accommodating the stator winding. And the first frame 112 of the insulating member 11 is closer to the rotation axis X than the second frame 113. The first frame 112 is provided with a limiting portion 1121. The first frame 112 has a guide surface 1120. The guide surface 1120 is located on a side of the first frame 112 away from the second frame 113. A plurality of wire loops 2 are stacked and installed on the insulating frame 1 in sequence along the axial direction of the rotation axis X. Along the stacking direction of the plurality of wire loops 2, the guide surface 1120 gradually moves away from the rotation axis X.

[0065] A winding space 110 for accommodating the stator winding is formed between the first frame 112 and the second frame 113 of the insulating member 11. When the stator winding is wound on the insulating body 111, each stator winding will generate tension, and each limiting portion 1121 on the insulating frame 1 is arranged at a radially inner position along the rotation axis X. The tension generated by the stator winding or the horizontal component of the tension will cause the limiting portion 1121 to deform radially inward, further interfering with the installation of the motor rotor. Therefore, a guide surface 1120 is provided on the side of the first frame 112 close to the rotation axis X, and the guide surface 1120 is gradually moved away from the rotation axis X along the stacking direction of the multiple knot rings 2, that is, it becomes an inclined surface. The inclination of the guide surface 1120 can be used to offset the radial deformation displacement of the limiting portion 1121 caused by the winding tension generated by the winding, thereby reducing the risk of the limiting portion 1121 interfering with the rotor installation.

[0066] In some embodiments, the first frame 112 is further provided with a connecting portion 1122. A winding space 110 is provided between the connecting portion 1122 and the second frame 113. The guide surface 1120 includes a first facet 112e and a second facet 112f. The first facet 112e is provided at the limiting portion 1121. The second facet 112f is provided at the connecting portion 1122. Along the stacking direction of the plurality of wire loops 2, the projection of the first facet 112e is farther from the rotation axis X than the projection of the second facet 112f.

[0067] When the stator winding is wound on the insulating body 111, it will occupy a certain winding space 110 along the axial direction of the rotation axis X to avoid axial interference between the stator winding and the wire tie ring 2. A connecting portion 1122 is further provided on the first frame 112, and the guide surface 1120 is respectively provided on the limiting portion 1121 and the connecting portion 1122 as the first facet 112e and the second facet 112f, so that the guide surface 1120 is formed into a structure in which two sections of inclined surfaces are connected, and along the stacking direction of multiple wire tie rings 2, the projection of the first facet 112e is farther away from the rotation axis X than the projection of the second facet 112f, and the angle of deviation of the first facet 112e from the rotation axis X is greater than that of the second facet 112f. Since the area of ​​the first frame 112 farther from the winding space 110 is more affected by the tension generated by the stator winding, the angle of the second facet 112f on the connecting portion 1122 close to the winding space 110 deviating from the rotation axis X is smaller than the first facet 112e to ensure the structural strength of the connecting portion 1122.

[0068] See also Figure 5 and Fig. 9 In some embodiments, the plurality of tie rings 2 include a three-phase tie ring 31 and a neutral point tie ring 32. The three-phase tie ring 31 is provided in a circumferential annular extension around the rotation axis X, and the angle of the annular extension of the three-phase tie ring 31 is less than 360°. Along the circumference of the rotation axis X, the three-phase tie ring 31 is provided with a plurality of electrical welding points 311. The plurality of electrical welding points 311 are arranged at intervals on the three-phase tie ring 31. The neutral point tie ring 32 is provided in a circumferential annular extension around the rotation axis X, and the angle of the annular extension of the neutral point tie ring 32 is equal to 360°. Along the circumference of the rotation axis X, the neutral point tie ring 32 is provided with a plurality of grounding welding points 321, and the plurality of grounding welding points 321 are arranged at intervals on the neutral point tie ring 32.

[0069] Since in a three-phase motor, the stator windings are arranged according to a certain rule to ensure that the generated magnetic field is balanced and uniform. Therefore, on each three-phase tie ring 31, the electrical welding points 311 electrically connected to the stator windings are arranged evenly spaced in the circumferential direction, and of course, the grounding welding points 321 on the neutral point connection ring are also arranged evenly spaced in the circumferential direction. The stator windings of each phase need to be grounded, so the neutral point tie ring 32 is a full circle structure. As far as the three-phase tie ring 31 of a single phase is concerned, the ring segment between two adjacent electrical welding points 311 is the position where the stator windings of other phases are electrically connected. Therefore, the ring segment between any two adjacent electrical welding points 311 is removed, and the annular extension angle of the three-phase tie ring 31 is designed to be less than 360°, which does not affect the transmission of current by the three-phase tie ring 31 to achieve material saving, and will not affect the assembly and fixation between each tie ring 2 and the insulating frame 1. At the same time, the three-phase wiring ring 31 is designed to be a non-circular structure, and the material can be overlapped in the mold design, so that it can be arranged more closely, and more three-phase wiring rings 31 can be produced, further reducing material costs.

[0070] The three-phase wiring loop 31 specifically includes a U-phase wiring loop 3101, a V-phase wiring loop 3102, and a W-phase wiring loop 3103. Figure 1 For example, along the circumferential direction of the rotation axis X, there are a total of twelve stator windings, so a three-phase tie ring 31 is provided with a total of four electrical welding points 311, and each is arranged at an interval of 90°. Therefore, the U-phase tie ring 3101, the V-phase tie ring 3102 and the W-phase tie ring 3103 are all designed to have a circumferential 270° structure. In some embodiments, according to the actual needs of different motors, the stator winding coils will have different parallel numbers, corresponding to different circumferential tie angles, that is, corresponding to the circumferential angle corresponding to the ring segment between two adjacent electrical welding points 311. Therefore, even if it is a motor with twelve stator windings, the U-phase tie ring 3101, the V-phase tie ring 3102 and the W-phase tie ring 3103 will be designed to have a structure less than 270° due to the parallel connection of the coils.

[0071] In some embodiments, there are multiple insulating members 11 . The multiple insulating members 11 are distributed in a ring around the rotation axis X. Each wire tie ring 2 is provided with multiple matching portions 21 . Each matching portion 21 of a wire tie ring 2 abuts against a limiting portion 1121 of an insulating member 11 .

[0072] A plurality of insulating parts 11 are distributed in a ring around the rotation axis X to form the entire insulating frame 1. A plurality of mating portions 21 on the wire tie ring 2 are also distributed on the wire tie ring 2 along the circumference of the rotation axis X. The plurality of mating portions 21 on each wire tie ring 2 are all in contact with a limiting portion 1121, thereby improving the fixing strength between the wire tie ring 2 and the insulating frame 1.

[0073] An embodiment of the present application provides a motor stator. Fig.10 The motor stator includes a stator core 4, a stator winding and a tie ring assembly 100. The stator core 4 is provided with a plurality of stator windings, and the insulating frame 1 includes a plurality of insulating members 11. Each insulating member 11 is sleeved on a stator core 4 (i.e., a single stator winding). Each stator winding is wound on an insulating member 11. Each stator winding is connected to the tie ring 2.

[0074] Each wire tie ring 2 is fixed to the insulating frame 1 by assembling the matching portion 21 and the limiting portion 1121, which ensures the current transmission function of the wire tie ring 2 itself while ensuring the structural strength of the wire tie ring 2 fixed in the motor stator, saving the material cost of the wire tie ring 2 and simplifying the assembly steps.

[0075] An embodiment of the present application provides a motor, which includes a motor rotor and a motor housing 5 , and also includes a motor stator, wherein the motor stator and the motor rotor are coaxially arranged in the motor housing 5 .

[0076] The connection method between the motor stator and multiple tie rings 2 in the motor is no longer to encapsulate the multiple tie rings 2 and then weld them to the insulating frame 1, but to first assemble the matching part 21 of the tie ring 2 and the limiting part 1121 of the insulating member 11 to obtain the tie ring assembly 100, and then the insulating member 11 is sleeved on the stator core 4 (in some embodiments, the stator silicon steel sheet group), and the stator winding is wound on the insulating member 11 to obtain the entire motor stator. The motor stator is installed in the motor housing 5 and encapsulated with an epoxy resin or varnish, which helps to improve the overall strength and reliability of the motor and saves the high cost of encapsulating multiple tie rings 2 into a tie ring group.

[0077] An embodiment of the present application provides a method for assembling a motor stator, which is used to assemble a motor housing 5 and a motor stator. Fig.12 As shown, the assembly method includes the following steps S1 to S3.

[0078] Step S1 , assembling a stator core 4 , a stator winding and an insulating member 11 into a stator structure 200 .

[0079] In some embodiments, a stator core 4 and an insulating member 11 are assembled so that the insulating body 111 of the insulating member 11 covers the stator core 4, and then a stator winding is wound on the insulating body 111 of the insulating member 11 to obtain a stator structure 200.

[0080] Step S2, assembling a plurality of tie rings 2 and a plurality of stator structures 200, and welding the stator winding of each stator structure 200 to the corresponding tie ring 2 to obtain a motor stator.

[0081] In some embodiments, multiple stator structures 200 are placed in a predetermined position in a circular arrangement around the rotation axis X of the motor rotor, and then each tie ring 2 is sequentially axially abutted against the stopper 1121 on the insulating member 11 in a predetermined order, so that each tie ring 2 is fixed to the insulating frame 1. Then, the two ends of the stator winding of each stator structure 200 are respectively welded to the grounding welding point 321 of the neutral point tie ring 32 and the electrical welding point 311 of the corresponding three-phase tie ring 31 to obtain the motor stator.

[0082] In some embodiments, multiple stator structures 200 and the matching parts 21 on the neutral point tie ring 32 can be assembled first, so that the multiple stator structures 200 are distributed in a ring around the rotation axis X of the motor rotor and fixed to the neutral point tie ring 32, and then the three-phase tie ring 31 is assembled with each stator structure 200 in sequence along the axial direction of the rotation axis X according to a preset order to complete the fixation between the multiple tie rings 2 and the insulating frame 1. Then, the two ends of the stator winding of each stator structure 200 are respectively welded to the grounding welding point 321 of the neutral point tie ring 32 and the electrical welding point 311 of the corresponding three-phase tie ring 31 to obtain the motor stator.

[0083] Step S3, installing the motor stator into the motor housing 5 and encapsulating it with glue.

[0084] In some embodiments, the motor stator is installed into the motor housing 5 along the axial direction of the rotation axis X, and the motor stator together with each wire tie ring 2 is potted in the motor housing 5 using epoxy resin or varnish.

[0085] Based on the connection structure between each tie ring 2 and the insulating frame 1, multiple tie rings 2 are directly assembled and connected with multiple stator structures 200 in sequence along the axial direction of the rotation axis X, so that multiple tie rings 2 and the insulating frame 1 are fixedly connected, and the connection strength is reliable. After the motor stator is assembled, it is encapsulated in the motor housing 5 by glue filling. The cost originally brought by the overmolding is saved, and each tie ring 2 can be well assembled on the motor stator, and the structural strength is reliable.

[0086] It is understandable that in some embodiments, the above steps can be combined with Fig.11 Execute as shown.

[0087] Based on step S1, the stator structure 200 after winding is completed is obtained. Fig.11As shown, step S2 is performed, and the neutral point tie ring 32 and the insulating frame 1 composed of each insulating member 11 are installed and fixed along the axial direction of the rotation axis X, and each matching groove 210 on the neutral point tie ring 32 will abut against a limit portion 1121. Similarly, the W-phase tie ring 3103, the V-phase tie ring 3102 and the U-phase tie ring 3101 are successively installed and fixed with the insulating frame 1 along the axial direction of the rotation axis X. Through the structural design of the limit portion 1121, each tie ring 2 and the insulating frame 1 have axial, circumferential and radial limits along the rotation axis X. Then, each stator structure 200 is electrically connected to the corresponding tie ring 2 to obtain an assembly structure of each stator structure 200 and each tie ring 2, that is, a motor stator. Step S3, along the axial direction of the rotation axis X, the motor stator is installed into the motor housing 5, and epoxy resin is poured in for packaging.

[0088] In addition, those skilled in the art should recognize that the above embodiments are only used to illustrate the present application and are not intended to be limiting of the present application. As long as they are within the spirit and scope of the present application, appropriate changes and modifications to the above embodiments are within the scope of the present application.

Claims

1. A wire tie ring assembly, arranged in a stator of a motor, characterized in that: include: An insulating frame, comprising an insulating member, wherein the insulating member is provided with a plurality of limiting portions, and the plurality of limiting portions are distributed along the rotation axis of the rotor of the motor; and A plurality of wire-tying rings are provided, each of which is provided with a mating portion, and the mating portion of each wire-tying ring abuts against the limiting portion of the insulating member, so that the plurality of wire-tying rings are fixed to the insulating frame along the axial direction of the rotation axis.

2. The wire tie ring assembly according to claim 1, characterized in that: Each of the limiting parts has a supporting surface, a first limiting surface and a second limiting surface; The supporting surface is configured to stop the wire loop axially along the rotation axis; the first limiting surface is configured to stop the matching portion circumferentially along the rotation axis; and the second limiting surface is configured to stop the matching portion radially along the rotation axis.

3. The wire tie ring assembly according to claim 2, characterized in that: A limiting protrusion is provided on the second limiting surface. In the same limiting portion, the limiting protrusion is configured to limit the movement of the wire tie ring along the axial direction of the rotation axis in a direction away from the supporting surface.

4. The wire tie ring assembly according to claim 2, characterized in that: Each of the mating parts is provided with a first mating surface and a second mating surface; the first mating surface and the second mating surface are distributed on opposite sides of the limiting part along the circumferential direction of the rotation axis, and Along the circumferential direction of the rotation axis, there is a gap between the limiting portion and the first matching surface and / or between the limiting portion and the second matching surface.

5. The wire tie ring assembly according to claim 4, characterized in that: Each of the mating parts is also provided with a third mating surface; along the circumferential direction of the rotation axis, the first mating surface, the third mating surface and the second mating surface are connected in sequence; The limiting portion is configured to be elastically deformable, and along the radial direction of the rotation axis, the second limiting surface abuts against the third matching surface and causes the limiting portion to be elastically deformed to apply an elastic force to the third matching surface.

6. The wire tie ring assembly according to claim 5, characterized in that: Each of the mating parts is provided with a mating groove, and one of the first mating surfaces, one of the third mating surfaces and one of the second mating surfaces is arranged to form one of the mating grooves, and each of the mating grooves accommodates one of the limiting parts.

7. The wire tie ring assembly according to claim 2, characterized in that: The tie loop has a first side and a second side disposed opposite to each other, and the support surface supports the first side; Along the axial direction of the rotation axis, the distance between the supporting surfaces of two adjacent limiting portions is greater than the distance between the first side and the second side of the same wire tie loop, so that the plurality of wire tie loops are electrically insulated from each other.

8. The wire tie ring assembly according to claim 1, characterized in that: The plurality of wire-binding rings are stacked and installed on the insulating frame in sequence along the axial direction of the rotation axis. Along the stacking direction of the plurality of wire-binding rings, the projection of one limiting portion of the insulating member covers the projection of an adjacent limiting portion.

9. The wire tie ring assembly according to claim 1, characterized in that: The insulating member includes an insulating body, a first frame and a second frame; the first frame and the second frame are arranged on the insulating body, Along the radial direction of the rotation axis, the first frame and the second frame of the insulating member are spaced apart to form a winding space for accommodating the stator winding, and the first frame of the insulating member is closer to the rotation axis than the second frame; The first frame is provided with the limiting portion; the first frame has a guide surface, and the guide surface is located on a side of the first frame away from the second frame; The plurality of wire-binding rings are stacked and installed on the insulating frame in sequence along the axial direction of the rotation axis, and along the stacking direction of the plurality of wire-binding rings, the guide surface gradually moves away from the rotation axis.

10. The wire tie ring assembly according to claim 9, characterized in that: The first frame is further provided with a connecting portion, and the winding space is provided between the connecting portion and the second frame; the guide surface includes a first facet and a second facet, the first facet is provided at the limiting portion, and the second facet is provided at the connecting portion; Along the stacking direction of the plurality of wire loops, the projection of the first facet is farther away from the rotation axis than the projection of the second facet.

11. The wire tie ring assembly according to any one of claims 1 to 10, characterized in that: The plurality of tie-in loops include a three-phase tie-in loop and a neutral point tie-in loop; The three-phase wire connection is arranged to extend in a circumferential ring around the rotation axis, and the angle of the three-phase wire connection ring is less than 360°; along the circumference of the rotation axis, the three-phase wire connection ring is provided with a plurality of electrical welding points, and the plurality of electrical welding points are arranged at intervals on the three-phase wire connection ring; The neutral point node line is arranged to extend in a circumferential ring around the rotation axis, and the angle of the neutral point node line ring extension is equal to 360°; along the circumference of the rotation axis, the neutral point node line ring is provided with a plurality of grounding welding points, and the plurality of grounding welding points are arranged at intervals on the neutral point node line ring.

12. The wire tie ring assembly according to any one of claims 1 to 10, characterized in that: There are multiple insulating parts, which are distributed in a ring around the rotation axis; each of the wire-tying rings is provided with multiple matching parts, and each matching part of a wire-tying ring abuts against a limiting part of a insulating part.

13. A motor stator, comprising a stator core and a stator winding, characterized in that: It also includes a tie-wire ring assembly as described in any one of claims 1 to 12; there are multiple stator cores, there are multiple stator windings, the insulating frame includes multiple insulating parts, each of the insulating parts is sleeved on one of the stator cores, each of the stator windings is wound on one of the insulating parts, and each of the stator windings is connected to the tie-wire ring.

14. A motor, comprising a motor rotor and a motor housing, characterized in that: It also includes the motor stator as claimed in claim 13, wherein the motor stator and the motor rotor are coaxially arranged in the motor housing.

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