A hollow cup motor

Abstract

The present invention provides a coreless motor, comprising: a stator assembly and a rotor assembly, wherein the stator assembly comprises at least one magnetic component; the rotor assembly comprises a printed circuit board disposed at both ends of the stator assembly, and an armature winding welded on the printed circuit board, wherein the armature winding comprises at least three windings, and both ends of each winding are respectively fixed on the printed circuit board; wherein each winding is in a straight line and parallel to the rotation center line of the rotor assembly. The coreless motor of the present invention has a PCB board disposed at both ends of the rotating shaft, so that the self-adhesive enameled wire in the armature winding of the coreless motor is in a straight line. Compared with the diamond structure of the prior art, the distribution coefficient of the armature winding can be effectively reduced, the utilization rate of the wire can be improved, and the output performance of the motor can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of coreless cup motors, and in particular to a coreless cup motor. Background Art

[0002] The coreless motor uses an iron coreless rotor. This rotor structure completely eliminates the power loss caused by the eddy current formed by the iron core. At the same time, its weight and moment of inertia are greatly reduced, thereby reducing the mechanical energy loss of the rotor itself. Due to the change in the rotor structure, the operating characteristics of the motor have been greatly improved. It not only has outstanding energy-saving characteristics, but more importantly, it has control and drag characteristics that iron core motors cannot achieve. Therefore, coreless motors are widely used in industrial robots, aircraft and other fields.

[0003] The current hollow cup motors mostly use Figure 1 The diamond winding winding, block-type or winding-type rounding process structure shown in the figure requires a copper wire to be wound into hundreds of oblique lines or diamond-shaped folded lines during the processing. The processing is difficult and the processing technology is complicated, resulting in the molded hollow cup motor having the disadvantages of uneven arrangement of the rotor armature winding, great difficulty in shaping, and a large distribution coefficient.

[0004] Therefore, it is necessary to provide an improved technical solution to address the above-mentioned deficiencies in the prior art. Summary of the invention

[0005] The object of the present invention is to provide a hollow cup motor, which has a neatly arranged rotor, low inertia and low distribution coefficient, and can improve product output performance, reduce rotational inertia and reduce response speed.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A coreless motor, comprising:

[0008] A stator assembly, the stator assembly comprising at least one magnetic member;

[0009] The rotor assembly is rotatably sleeved outside the stator assembly, and the rotor assembly includes:

[0010] A printed circuit board, wherein the printed circuit board is arranged at two ends of the stator assembly;

[0011] An armature winding, the armature winding is welded on the printed circuit board, the armature winding comprises at least three windings, and two ends of each winding are respectively fixed on the printed circuit board;

[0012] Wherein, each of the windings is in a straight line and parallel to the rotation center line of the rotor assembly.

[0013] Furthermore, the stator assembly also includes a bushing, which is in a hollow tubular shape and is embedded in the magnetic component.

[0014] Furthermore, the rotor assembly also includes a rotating shaft, and the rotating shaft is rotatably disposed in the bushing.

[0015] Furthermore, the rotor assembly also includes a commutator, which is disposed at one end of the stator assembly and fixed between the printed circuit board and the rotating shaft to change the current direction of the armature winding.

[0016] Furthermore, the printed circuit board is provided with wire grooves and positioning holes, the wire grooves are evenly arranged along the outer circumference of the printed circuit board, and the positioning holes are provided at the inner circumferential edge of the printed circuit board for fixing the PCB board.

[0017] Furthermore, the printed circuit board includes N layers, the N layers of printed circuit boards are connected in parallel, and N≥2.

[0018] Furthermore, the winding adopts a self-adhesive enameled wire, and the self-adhesive enameled wire is inserted into a wire groove of a printed circuit board.

[0019] Furthermore, the magnetic member is a magnetic steel, and the magnetic steel and the bushing are bonded with glue.

[0020] Furthermore, the bushing is rollingly connected to the rotating shaft through bearings on both sides.

[0021] Furthermore, the stator assembly, the rotor assembly and the rotating shaft are concentric and in the same horizontal plane.

[0022] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0023] Due to the PCB boards arranged at both ends of the rotating shaft of the hollow cup motor of the present invention, the self-adhesive enameled wire in the armature winding of the hollow cup motor is straight. Compared with the diamond structure of the prior art, the distribution coefficient of the armature winding can be effectively reduced, the utilization rate of the wire is improved, and the output performance of the motor can be improved.

[0024] The armature winding of the present invention uses a hot-melt (or alcohol) self-adhesive enameled wire. After the winding is completed, the hot-melt paint of the self-adhesive enameled wire is melted by heating. Under the action of the rotating centrifugal force, the hot-melt paint is evenly distributed between the windings. After the hot-melt paint at room temperature is cured, the strength of the motor rotor cup will be greatly increased. Compared with ordinary enameled wire, the armature winding using hot-melt (or alcohol) self-adhesive enameled wire can effectively enhance the strength of the middle part of the hollow cup motor rotor cup. Moreover, after the hollow cup winding is wound, there is no need for subsequent shaping, which can ensure the neatness of the arrangement of the self-adhesive enameled wire inside the armature winding, so that the thickness of the rotor cup can be reduced to a certain extent, so that the number of windings of the self-adhesive enameled wire inside the rotor cup can be further increased.

[0025] The present invention adopts the form of PCB board welding, and the winding connections on both sides of the hollow cup rotor are welded on the welding pads of the PCB board, and the electrical connection is realized through the inside of the PCB board, which can greatly reduce the end resistance and the size of the end self-adhesive enameled wire, and the material density of the PCB board is much smaller than that of the copper wire, and can also reduce the weight of the entire hollow cup motor and the rotational inertia of the hollow cup motor, thereby improving the response speed of the hollow cup motor.

[0026] Based on the various effects analyzed above, it can be seen that the present invention can be applied to the mass production of hollow cup motors with low winding density and large winding wire diameter, thereby improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0028] Figure 1 It is a schematic diagram of the diamond winding structure of the existing hollow cup motor rotor;

[0029] Figure 2 It is a structural cross-sectional view of the coreless cup motor of the present invention;

[0030] Figure 3 This is a schematic diagram of the linear winding structure of the hollow cup motor of the utility model;

[0031] Figure 4 This is a schematic diagram of the side structure of the PCB board in the hollow cup motor of the present invention;

[0032] Figure 5 It is a schematic diagram of the three-dimensional structure of the PCB board in the hollow cup motor of the present invention;

[0033] Figure 6 It is a schematic diagram of the armature winding tooling and installation of the present invention.

[0034] In the figure: 1. rotating shaft; 2. magnetic steel; 3. armature winding; 4. bushing; 5. commutator; 6. PCB board; 7. first winding tooling; 8. second winding tooling; 9. ejector pin hole; 10. solder joint; 11. positioning hole; 12. line connection structure; 13. self-adhesive enameled wire. DETAILED DESCRIPTION

[0035] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present invention and does not limit the present invention. In fact, it will be clear to those skilled in the art that modifications and variations may be made in the present invention without departing from the scope or spirit of the present invention. For example, a feature shown or described as a part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desired that the present invention encompasses such modifications and variations within the scope of the appended claims and their equivalents.

[0036] In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. The terms "connected", "connected" and "set" used in the present invention should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection; it can be a direct connection or an indirect connection through an intermediate component; it can be a wired electrical connection, a radio connection, or a wireless communication signal connection. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0037] The structure of the coreless motor of the present invention is as follows Figure 2 As shown, it includes an outer shell, a stator assembly and a rotor assembly; the stator assembly and the rotor assembly are both installed in the outer shell.

[0038] The stator assembly includes a magnet 2 and a bushing 4, and the magnet 2 and the bushing 4 are assembled. Specifically, the magnet 2 is sleeved on the outer circumferential surface of the bushing 4, and the magnet 2 is arranged axially close to one end of the bushing 4. The magnet 2 and the bushing 4 are bonded with anaerobic adhesive. When bonding, rotating the magnet 2 will make the anaerobic adhesive evenly distributed between the magnet 2 and the bushing 4, and the bonding will be more firm. In this embodiment, anaerobic adhesive is used to bond the magnet to the bushing. As other implementation methods, structural adhesives and epoxy glues can also be selected; the bushing 4 is made of high-strength magnetic conductive materials, such as 2Cr13 / 10# steel and other metal materials; the magnet 2 is a hollow cylindrical NdFeB magnetic material component. The magnet 2 can be an integrally formed magnetic part, or a combined magnetic part including multiple sections of the magnet 2.

[0039] The stator assembly is sleeved on the rotating shaft 1 of the rotor assembly through the bearings installed in the grooves on both sides of the bushing 4, the magnetic steel 2 is embedded in the hollow part of the rotor, and the rolling connection between the rotor assembly and the stator assembly is achieved through the bearings on both sides of the bushing 4. The rotor assembly and the stator assembly maintain the same concentricity.

[0040] The rotor assembly is rotatably mounted on the stator assembly, and the rotor assembly includes an armature winding 3, a commutator 5 and a set of printed circuit boards, i.e., PCB boards 6; a set of PCB boards 6 are respectively arranged at both ends of the rotor assembly, i.e., along both ends of the rotating shaft 1, for fixing the winding tooling of the armature winding 3, and can also connect the armature winding 3 and the commutator 5, so as to support the armature winding 3.

[0041] The commutator 5 is arranged between the inner circumference of the PCB board 6 and the outer circumference of the rotating shaft 1, the inner circle of the commutator 5 is tightly connected to the rotating shaft 1, and the outer circle of the commutator 5 is welded and glued to the armature winding 3, so that the armature winding 3, the PCB board 6, the commutator 5, and the rotating shaft 1 are connected as a mechanical whole to form a rotor. During the operation of the hollow cup motor, due to the commutation work of the commutator 5, the current direction of the armature winding 3 is changed, and the hollow cup motor is controlled to work normally under continuous current.

[0042] The side structure of the PCB board 6 on both sides of the hollow cup armature winding is as follows Figure 4 As shown, the PCB board 6 includes a positioning hole 11, a line connection structure 12 and a wire groove. The wire groove is arranged along the outer circumference of the PCB board and is used to pass the self-adhesive enameled wire 13. The line connection structure 12 is used to realize the electrical connection in the PCB board. The positioning hole is opened at the inner circumferential edge of the PCB board. The PCB board 6 can be kept concentric with the rotating shaft 1 by fixing the positioning hole 11.

[0043] The windings of the armature winding 3 are laser welded to the designated pads of the PCB board 6 and welded to the solder joints 10 of the PCB board at both ends. Figure 3 As shown, the armature winding 3 is parallel to the axis of the rotating shaft 1, that is, the armature winding is a linear structure, and the armature winding 3 is spaced from the outer surface of the magnetic steel 2 and is parallel to the rotation center line of the rotor assembly. A number of self-adhesive enameled wires in the armature winding 3 are sequentially welded to corresponding positions of the PCB board 6, the internal electrical grouping of the armature is the same as the number of sheets inside the commutator 5, and the armature winding 3 realizes different connection modes through the circuit connection structure 12 inside the PCB.

[0044] Based on the structural features of the rotor assembly described above, the rotor assembly of the present invention is a cylindrical structure with a hollow interior.

[0045] Considering the size limitation of actual laser welding, when the number of turns is large, N layers of PCB boards are connected in parallel. To ensure the concentricity of the N layers of PCB boards D, each layer of PCB boards is fixed through the positioning holes 11, so that the N layers of PCB boards are concentric with the shaft 1. In this embodiment, a three-layer PCB board is used, and its three-dimensional structure is as follows: Figure 5 As shown, the three-layer PCB board is also connected in parallel, specifically, the three PCB boards are adhered with glue to achieve parallel connection and fixation of the PCB boards.

[0046] The installation of the coreless motor of the present invention is to install the bushing 4, the rotating shaft 1, the magnetic steel 2, the PCB board 6, the first winding tool 7, and the second winding tool 8 on the machine tool; and then perform the following specific steps:

[0047] (1) Installation of stator assembly: The stator assembly is composed of a magnet 2 and a bushing 4. Since the through holes on both sides of the armature winding of the hollow cup motor structure are relatively small, the internal stator assembly can only be installed in place before the armature winding is wound. Specifically, the bushing 4 is first fixed to the rotating shaft 1 through the bearings on both sides thereof, and then the magnet 2 is glued to the bushing 4, thereby realizing the internal installation of the stator assembly first.

[0048] (2) Rotor assembly installation: Figure 6 In the method shown, the PCB board 6 on both sides of the stator assembly is first supported by the first winding fixture 7 and the second winding fixture 8, and the shape and position tolerances of various components are ensured; there are positioning holes 11 on both sides of the second winding fixture 8, and the PCB boards 6 at both ends are fixed to the machine tool through the ejector holes 9 using an ejector pin, and then the PCB boards 6 are fixedly installed through the positioning holes 11, thereby achieving the concentricity of the PCB boards 6 at both ends and the rotating shaft 1.

[0049] (3) Winding installation: After the above rotor assembly is fixed on the machine tool, follow the steps below: Figure 6 The tooling steering direction shown in the figure controls the machine tool to rotate at a constant speed, which can ensure the uniform and neat arrangement of the self-adhesive enameled wire inside the winding of one circle. When the tooling is in place, the winding wire is straightened and fixed to the wire grooves of the PCB board at both ends, and then welded; after completion, it moves to the next position and repeats the above steps; after completing one layer of PCB board, the excess self-adhesive enameled wire is cut off, the solder joints are shaped, and the next layer of PCB board is installed, and the winding continues;

[0050] (4) Curing and shaping of the rotor assembly: After winding, the assembly is placed on a rotating platform and the self-adhesive enameled wire is heated. Centrifugal force is used to prevent the melted self-adhesive paint from entering the air gap inside the motor. After curing, a glass fiber epoxy reinforcement layer is added to the outer circle of the cup-shaped armature winding to improve the overall mechanical strength.

[0051] (5) Assembly: First remove the second winding fixture, and install the shaft 1 and commutator 5 at the position of the second winding fixture 8. As another embodiment, the second winding fixture 8 can be directly replaced by the shaft 1. Correspondingly, after winding, shaping, and welding, only the commutator 5 can be directly installed at the corresponding position. Then apply glue between the components to tighten and fix them, and then remove the first winding fixture 7 after fixing and forming, until the overall size is processed in place and tested to be qualified, and all installations are completed.

[0052] The present invention installs each component according to the above steps, and during installation, attention should be paid to the installation position to ensure the concentricity of each component and the rotating shaft 1. If there are more windings, more layers of PCB boards can be used, and the installation method of subsequent layers is the same as that of the first layer, and the relative position of the winding installation is determined according to the actual design requirements.

[0053] Based on the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0054] The self-adhesive enameled wire inside the hollow cup armature is straight-line, rather than the ordinary diamond-shaped structure, which can effectively reduce the winding distribution coefficient and improve the wire utilization rate, thereby improving the output performance of the motor. At the same time, this structure can enhance the strength of the middle part of the rotor cup;

[0055] After the hollow cup winding is completed, there is no subsequent shaping step, which can improve the neatness of the winding arrangement inside the armature, reduce the thickness of the rotor cup to a certain extent, and increase the number of self-adhesive enameled wires inside the rotor cup;

[0056] The winding connection on both sides of the hollow cup rotor is in the form of PCB board welding, and the two opposite wires inside the armature are connected through the internal routing of the PCB board, which greatly reduces the end resistance and the size of the end self-adhesive enameled wire. The material density of the PCB board is much smaller than that of the copper wire. This structure can also reduce the gravity of the entire rotor cup and reduce the moment of inertia, which is beneficial to improve the response speed of the hollow cup motor.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A coreless motor, characterized in that: include: A stator assembly, the stator assembly comprising at least one magnetic member; The rotor assembly is rotatably sleeved outside the stator assembly, and the rotor assembly includes: A printed circuit board, wherein the printed circuit board is arranged at two ends of the stator assembly; An armature winding, the armature winding is welded on the printed circuit board, the armature winding comprises at least three windings, and two ends of each winding are respectively fixed on the printed circuit board; Wherein, each of the windings is in a straight line and parallel to the rotation center line of the rotor assembly.

2. The coreless motor according to claim 1, characterized in that: The stator assembly further comprises a bushing which is in a hollow tubular shape and is embedded in the magnetic component.

3. The coreless motor according to claim 2, characterized in that: The rotor assembly also includes a rotating shaft, which is rotatably disposed in the bushing.

4. The coreless motor according to claim 3, characterized in that: The rotor assembly further comprises a commutator, which is arranged at one end of the stator assembly and fixed between the printed circuit board and the rotating shaft, and is used for changing the current direction of the armature winding.

5. The coreless motor according to claim 1, characterized in that: The printed circuit board is provided with wire grooves and positioning holes, the wire grooves are evenly arranged along the outer circumference of the printed circuit board, and the positioning holes are provided at the inner circumference edge of the printed circuit board for fixing the PCB board.

6. The coreless motor according to claim 1, characterized in that: The printed circuit board comprises N layers, the N layers of printed circuit boards are connected in parallel, and N≥2.

7. The coreless motor according to claim 1, characterized in that: The winding adopts self-adhesive enameled wire, and the self-adhesive enameled wire is passed through the wire groove of the printed circuit board.

8. The coreless motor according to claim 2, characterized in that: The magnetic member is a magnetic steel, and the magnetic steel and the bushing are bonded with glue.

9. The coreless motor according to claim 4, characterized in that: The bushing is rollingly connected with the rotating shaft through bearings on both sides.

10. The coreless motor according to claim 3, characterized in that: The stator assembly, the rotor assembly and the rotating shaft are concentric in the same horizontal plane.

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