CN113422456A

CN113422456A - Brushless motor and stator assembly and manufacturing method thereof

Info

Publication number: CN113422456A
Application number: CN202110776125.3A
Authority: CN
Inventors: 朱建晓
Original assignee: Suzhou Konig Electronic Technology Co ltd
Current assignee: Suzhou Konig Electronic Technology Co ltd
Priority date: 2021-07-09
Filing date: 2021-07-09
Publication date: 2021-09-21

Abstract

The invention discloses a brushless motor with better waterproof protection insulating property, a stator assembly thereof and a manufacturing method, wherein the stator assembly of the brushless motor comprises the following components: a stator support; the coil winding is fixedly arranged on the stator bracket; the coil winding includes a plurality of coils arranged in a circumferential direction; an insulator made of hot melt adhesive; the insulator covers the plurality of coils; the insulator has an insulating spacer filled between two adjacent coils.

Description

Brushless motor and stator assembly and manufacturing method thereof

Technical Field

The invention relates to the field of motors, in particular to a brushless motor, a stator assembly of the brushless motor and a manufacturing method of the stator assembly.

Background

In the prior art, as a direct current brushless motor which is widely used in the market, a rotor and a stator are usually formed by winding silicon steel sheets and coils, and then are fixed on a motor shell or a motor base, meanwhile, the central line of the coil is vertical to the plane of a permanent magnet sheet of the rotor, the coil is exposed in the air, and the insulation paint scratch or high-voltage breakdown of the motor coil causes harm to the safety of a human body.

In some solutions, in order to avoid the circuit board connected with the motor from being exposed, sometimes a pouring sealant or a high-pressure high-temperature injection molding sealing shell is utilized for waterproof protection, however, the reject ratio of the circuit board is high by adopting the process, and the service life of the equipment is also adversely affected.

Disclosure of Invention

The inventor finds that due to the fact that the pressure temperature of glue liquid is high or the heat generated in the curing reaction is high when high-pressure high-temperature injection molding is carried out, the components of the circuit board can be burnt to a certain degree, the electronic components need to bear the pressure brought by the glue liquid, the electronic components of the circuit board are further easily damaged, and high reject ratio is caused.

And the casting glue is because the material carries out chemical reaction when the curing reaction, and inside material property changes, and the material is inside to bring the shrink fastening, and then the casing self inside after the casting glue solidification that holds electronic components can have great material stress, and these stresses are exerted on electronic components, not only harm electronic components easily, also can bring harmful effects to the life of circuit board moreover.

In addition, the potting adhesive enters the pre-prepared potting blank through self flowing, the curing time is long under the condition of high viscosity, the shell is not compact enough, an un-potted area is easy to exist in the shell, and the quality of the shell such as waterproof sealing or insulation protection is affected.

Furthermore, a significant problem with using potting compound to form a sealed enclosure is that the workpiece is placed into a potting compound prior to potting and then the potting compound is injected and cured, after curing, the potting compound and the potting compound become an integral body that together forms the outer enclosure for the workpiece. Therefore, the encapsulation process needs to provide an encapsulation blank for each workpiece in advance, so that the manufacturing cost is increased, the manufacturing time is long, and the manufacturing efficiency is seriously influenced.

In view of the above problems, the present invention provides a brushless motor, a stator assembly thereof, and a manufacturing method thereof, so as to solve at least one of the above problems.

In order to achieve the purpose, the invention adopts the following technical scheme:

a stator assembly of a brushless motor, comprising:

a stator support;

the coil winding is fixedly arranged on the stator bracket; the coil winding includes a plurality of coils arranged in a circumferential direction;

an insulator made of hot melt adhesive; the insulator covers the plurality of coils; the insulator has an insulating spacer filled between two adjacent coils.

As a further aspect of the present invention, the insulator extends continuously in a circumferential direction.

As a further aspect of the present invention, the stator assembly has a central through hole; the inner wall of the stator frame is not covered by the insulator; the inner wall of the stator holder and the inner wall of the insulator constitute an inner wall of the central through hole extending continuously in the circumferential direction.

As a further aspect of the present invention, the stator frame has stator teeth surrounded by the coil; the insulator covers the coil inside, and inner end faces of the stator teeth in the radial direction are not covered with the insulator to be exposed.

As a further aspect of the present invention, the stator assembly has a central through hole; the inner end surfaces of the stator teeth in the radial direction and the inner wall of the insulator participate in forming the inner wall surface of the central through hole.

As a further aspect of the present invention, the stator bracket includes a magnetic conductive ring body and an insulating frame fixed inside the magnetic conductive ring body; the insulating framework is provided with a plurality of stator teeth for winding the coil, and inner end surfaces of the stator teeth face to the inner side in the radial direction; the insulator extends inwards from the magnetic conductive ring body to the inner end surface in the radial direction.

As a further aspect of the present invention, the stator assembly has stator teeth surrounded by the coil; the insulator covers the coil inside, and the outer end faces of the stator teeth in the radial direction are not covered with the insulator to be exposed.

As a further aspect of the present invention, the stator frame further has an inner ring body; the plurality of stator teeth are uniformly and fixedly arranged on the outer side of the inner ring body along the circumferential direction; the stator teeth extend radially outward from the inner ring body; the outer end faces of the stator teeth and the outer wall face of the insulator are approximately on the same cylindrical surface.

As a further aspect of the present invention, the outer end surfaces of the stator teeth and the outer wall surface of the insulator constitute an outer wall surface of the stator assembly that extends continuously in a circumferential direction.

As a further proposal of the invention, the motor is also provided with a circuit board fixedly arranged on the stator bracket; the circuit board is electrically connected with the coil; at least a part of the circuit board is covered by a protective body made of hot melt adhesive molded by low-temperature and low-pressure injection molding.

As a further scheme of the invention, the stator bracket is provided with a stator magnetic conduction bracket and an insulation framework for accommodating the stator magnetic conduction bracket; the coil is wound on the insulating framework; the circuit board is fixed on the insulating framework.

As a further aspect of the present invention, the insulator further includes a filling portion filled between the insulating bobbin and the stator magnetic conductive bracket.

As a further aspect of the present invention, the protective body and the insulator are formed in an integral injection molding structure.

A brushless electric machine comprising a stator assembly as claimed in any preceding claim.

A method of manufacturing a stator assembly of a brushless motor, comprising the steps of:

placing the stator support wound with a plurality of coils into a cavity of a mold; wherein, the inner wall of the stator bracket is fitted and sleeved outside a filling rod; the cavity at least provides a glue solution injection space outside the coil;

and injecting hot melt adhesive in a molten state into the cavity through low-pressure injection molding equipment, wherein the hot melt adhesive is solidified to form an insulator which coats the coils and forms an insulating interval part between every two adjacent coils.

As a further scheme of the present invention, the cavity further provides a glue solution injection space outside the stator support, and accordingly, the coil and the stator support are coated after the hot melt glue is cured.

As a further scheme of the invention, the method also comprises the following steps: fixedly assembling the circuit board on the stator bracket;

the manufacturing method comprises the following steps:

putting the stator bracket wound with a plurality of coils and the circuit board into a cavity of a mold;

and injecting a hot melt adhesive in a molten state into the cavity, wherein the hot melt adhesive is solidified to form an insulator for coating the coils and a protective body for covering at least one part of the circuit board.

As a further scheme of the invention, the cavity provides a glue injection space for injecting the stator bracket wound with a plurality of coils and the glue surrounded by the circuit board; the manufacturing method comprises the following steps: and injecting a molten hot melt adhesive into the cavity, and forming an external shell which coats the stator support wound with the plurality of coils and the circuit board inside after the hot melt adhesive is solidified.

Has the advantages that:

according to the stator assembly of the brushless motor, the coil is insulated and protected by providing the insulator made of the hot melt adhesive and coated outside the coil winding, the coil and insulating paint of the coil are prevented from being scratched, the insulating capacity between the coils can be improved through the insulating partition part, and the danger brought to a human body by high-voltage breakdown is reduced.

In addition, the circuit board of the stator assembly is covered by the protective body made of the hot melt adhesive formed by low-temperature and low-pressure injection molding, so that better insulation protection can be provided, electronic components of the circuit board can be protected from being damaged, and meanwhile, the circuit board and the peripheral structure can be more easily matched.

Specific embodiments of the present invention are disclosed in detail with reference to the following description and drawings, indicating the manner in which the principles of the invention may be employed. It should be understood that the embodiments of the invention are not so limited in scope. The embodiments of the invention include many variations, modifications and equivalents within the spirit and scope of the appended claims.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments, in combination with or instead of the features of the other embodiments.

It should be emphasized that the term "comprises/comprising" when used herein, is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps or components.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.

Fig. 1 is a perspective view of a stator assembly of a brushless motor according to one embodiment of the present invention.

Fig. 2 is a sectional view of fig. 1.

Fig. 3 is another cross-sectional view of fig. 1.

Fig. 4 is a schematic view of the stator magnetic permeable support of fig. 1.

Fig. 5 is an exploded view of the internal structure of fig. 1.

Fig. 6 is a perspective view of a stator assembly of a brushless motor according to another embodiment of the present invention.

Fig. 7 is a schematic pre-encapsulation view of fig. 6.

Fig. 8 is an exploded view of fig. 7.

Fig. 9 is a schematic cross-sectional view of fig. 6.

Fig. 10 is a perspective view of a stator assembly of a brushless motor according to another embodiment of the present invention.

Fig. 11 is an exploded view of the fig. 10 pre-encapsulated structure.

Description of reference numerals: 1. a stator support; 2. an insulator; 15. a coil; 20. an insulating spacer; 21. an outer insulating ring portion; 22. an inner insulating ring portion; 25. an intermediate insulating ring portion; 100. a stator magnetic conductive bracket; 140. heat dissipation holes; 200. an insulating framework; 210. a first skeleton; 211. an insertion portion; 212. a flat portion; 213. a slot; 220. a second skeleton; 280. a positioning cylinder; 230. an annular accommodating groove; 231. stator teeth; 10. a stator lamination; 101. an inner ring body; 102. a stator through hole; 103. an outer convex portion; 104. a tooth end; 105. an inner groove portion; 1011. an inner magnetically conductive wall surface; 1041. an outer magnetically conductive wall surface; 300. a circuit board; 400. a cable; 500. a central through hole.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1 to 5, an embodiment of the present invention provides a stator assembly of a brushless motor, including: a stator frame 1; a coil winding fixedly arranged on the stator bracket 1; an insulator 2 made of hot melt adhesive. Wherein the stator assembly is configured to have a central through hole 500 through which the motor shaft passes. The motor shaft passes through the stator assembly and extends out of the stator assembly at both ends. The coil winding includes a plurality of coils 15 arranged in a circumferential direction. The insulator 2 covers the plurality of coils 15. The insulator 2 has an insulating spacer 20 filled between two adjacent coils 15. Insulator 2 adopts low temperature low pressure hot melt adhesive material, can the short time shaping, promotes production efficiency. In addition, the insulator 2 made of the hot melt adhesive can be subjected to injection molding by adopting low-pressure injection molding equipment, and an injection mold can be repeatedly used, so that the manufacturing cost can be effectively reduced.

Insulator 2 adopts the hot melt adhesive to make, has the insulating properties of preferred, avoids forming between coil 15 and punctures the destruction, promotes the insulating properties between coil 15 to still having magnetic field penetrability, avoiding producing harmful effects to the produced magnetic field of stator module coil 15, on the basis of promoting stator module's waterproof insulation barrier property, also guaranteed the produced magnetic field intensity of stator module.

The stator module of the brushless motor provided by the embodiment carries out insulation protection on the coil 15 by providing the coated insulator 2 made of the hot melt adhesive outside the coil winding, avoids the coil 15 and insulating paint thereof from being scratched, can also improve the insulating capability between the coils 15 through the insulation spacing part 20, and reduces the danger brought to a human body by high-voltage breakdown.

The insulator 2 encloses the coil 15 inside thereof in a manner not to expose the surface. Specifically, the insulator 2 extends continuously along the circumferential direction, and the plurality of coils 15 are wrapped inside, so that the coils 15 are prevented from being exposed, and the overall insulation protection performance of the stator assembly is improved. The insulator 2 has a cylindrical structure (cylindrical structure) as a whole. The stator assembly has a central through bore 500. The inner wall of the stator frame 1 is not covered by the insulator 2. The inner walls of the spacer insulators and the inner wall of the stator holder 1 are substantially flush to constitute a circumferentially continuous smooth surface. The inner wall of the stator holder 1 and the inner wall of the insulator 2 constitute an inner wall of the central through hole 500 continuously extending in the circumferential direction.

The stator frame 1 has stator teeth 231 surrounded by the coil 15. One end of the stator teeth 231 in the radial direction is provided with a tooth end 104. The outer surface of the tooth end 104 on the side away from the inner ring or the outer surface of the radially outer end is not covered with the insulator 2 to be exposed. The outer wall of the insulator 2 and the outer surface of the tooth end 104 not covered by the insulator 2 participate in constituting the outer circumferential surface of the stator assembly.

The stator support 1, the coil winding and the insulator 2 are coaxially arranged around the central through hole 500. The outer surfaces of a plurality of the tooth tips 104 are arranged in the circumferential direction. The surface of the insulator 2 constituting the central through hole 500 is substantially on the same cylindrical surface as the outer surface of the tooth tip 104. The plurality of coils 15 are arranged in the circumferential direction. The stator frame 1 provides support for the plurality of coils 15, and the plurality of coils 15 are arranged in the circumferential direction. The insulator 2 has an adhesion surface to which the coil 15 and the stator teeth 231 are adhered.

In the embodiment shown in fig. 1 to 6, the stator frame 1 includes a stator magnetic conductive frame 100, and an insulating frame 200 accommodating the stator magnetic conductive frame 100. The stator teeth 231 extend radially outward from the inner ring body 101. The end surface of the stator tooth 231 at the outer end in the radial direction is substantially on the same cylindrical surface as the outer wall surface of the insulator 2. The end faces of the stator teeth 231 at the radially outer ends are not covered with the insulator 2 to be exposed.

In this embodiment, the stator assembly has stator teeth 231 surrounded by the coils 15. The insulator 2 covers the coil 15 inside, and the outer end faces of the stator teeth 231 in the radial direction are not covered with the insulator 2 to be exposed. The outer end faces of the stator teeth 231 are exposed on the outer wall face of the stator assembly and are not covered by the insulator 2, forming an outer magnetically conductive wall face 1041 to expose the polarity, ensure the intensity of the formed magnetic field, and drive the rotor.

In the present embodiment, as shown in fig. 3, the stator frame 1 includes a stator magnetic conductive frame 100 such as a stator core, and the stator magnetic conductive frame 100 includes stator laminations 10 stacked in an axial direction. The individual stator laminations 10 are of unitary construction. The stator frame 1 also has an inner ring body 101. The inner ring body 101 has a stator through hole 102 at the center. The plurality of stator teeth 231 are uniformly fixed on the outer side of the inner ring body 101 along the circumferential direction. The stator teeth 231 extend radially outward from the inner ring body 101. The outer end surfaces of the stator teeth 231 are substantially on the same cylindrical surface as the outer wall surface of the insulator 2. The outer end face of the stator tooth 231 and the outer wall face of the insulator 2 form an outer wall face of the stator assembly which extends continuously in the circumferential direction, and outer insulating ring portions 21 are formed on both axial sides of the outer magnetic conductive wall face 1041.

The stator magnetic carrier 100 comprises a (stator) core, which may be formed by a plurality of laminated silicon steel sheets (stator laminations 10). The stator permeable support 100 has an inner race. The inner ring has a through hole which is configured as a part (substantially the middle part) of the central through hole 500. The plurality of outward protrusions 103 extend radially outward from the inner ring, and are uniformly arranged on the circumferential outer side of the stator magnetic permeable support 100 in the circumferential direction. The radially outer end of the male protrusion 103 forms a tooth tip 104. An inner groove 105 is formed between two adjacent outer convex parts 103. The inner magnetic conductive wall surface 1011 of the center through hole 500 is provided by the inner wall of the inner ring of the stator magnetic conductive bracket 100, and the insulator 2 forms the inner insulating ring portions 22 on both sides of the inner magnetic conductive wall surface 1011.

The stator frame 1 has an inner ring body 101. The plurality of stator teeth 231 are uniformly arranged on the outer side of the inner ring body 101. The stator teeth 231 and the inner ring body 101 may be integrally formed. The stator holder 1 and the coil 15 are covered inside the insulator 2. The stator teeth 231 extend radially from the inside to the outside. The outer end faces of the stator teeth 231 face radially outward. The insulating spacers 20 extend in the axial direction on both sides of the outer end surface of the stator tooth 231, and are continuous in the circumferential direction at both axial ends of the stator tooth 231, thereby surrounding the outer end surface of the stator tooth 231.

As shown in fig. 6, 9, and 10, the outer wall surface between two adjacent stator teeth 231 is provided by the insulating spacer 20. The outer wall surface of the insulating spacer 20 is substantially flush with the outer end surface of the stator tooth 231, and constitutes a substantially cylindrical outer wall surface of the stator assembly. The insulator 2 provides a cavity for accommodating the coil 15, which is formed depending on the outer shape of the coil 15, tightly packing the coil 15 inside.

In this embodiment, the stator assembly further has a circuit board 300 fixedly disposed on the stator frame 1. The circuit board 300 may be a sensor substrate, or a control circuit board 300 such as a control of a rotational speed. The circuit board 300 is integrated with the stator assembly and is extended out of the protective body through a lead to connect other devices. The circuit board 300 is electrically connected to the coil 15. At least a part of the circuit board 300 is covered with a protective body made of a hot melt adhesive molded by low-temperature and low-pressure injection molding. The insulator 2 and the protector enclose the stator frame 1, the coil 15, and the circuit board 300 in the interior thereof in the form of an enclosure. The circuit board 300 is electrically connected with a cable 400 which passes through the protective body.

This stator module's circuit board 300 is covered by the protective body of low temperature low pressure injection moulding's hot melt adhesive system, can provide the insulation protection of preferred to electronic components that can protect circuit board 300 is not damaged, and simultaneously, the cooperation is changeed with peripheral structure to the circuit board 300 of being convenient for.

Preferably, the protection body and the insulator 2 are of an integral injection molding structure. The present embodiment integrally provides the shielding member of the circuit board 300 and the insulator 2 of the coil 15, thereby avoiding multiple molding processes and effectively improving the manufacturing efficiency. The low-pressure injection molded protector (insulator 2 or cover) is injected into the mold at an injection pressure of 10MPa or less. In the high-pressure injection molding process, the injection pressure is generally over 40MPa, and further, the hot melt adhesive curing and molding method provided by the embodiment cannot damage elements with limited compression resistance, and has better product adaptability.

The hot melt adhesive of insulator 2 has injection pressure in pouring into the mould, and not only the casing material that forms is inseparabler, but also can flow into and fill in the gap between the device, avoids inside device not hard up, to forming the interval buffering between the device, forms an organic whole structure with device integration for stator module itself has the structural strength of preferred, possess longer life.

In the present embodiment, the stator frame 1 has a central through hole 500. The inner wall surface of the stator holder 1 is not covered with the insulator 2, and forms a magnetically conductive wall surface extending continuously in the circumferential direction. The two axial sides of the magnetic conduction wall surface are respectively provided with an insulation wall surface which extends continuously in the circumferential direction. The inner wall surface of the central through hole 500 has a magnetically conductive wall surface and insulating wall surfaces located on both axial sides of the magnetically conductive wall surface. This continuous extension's magnetic conduction wall conveniently rivets an central siphon (for example copper body), conveniently penetrates the central siphon with the pivot in, and the pivot is by the rotor fixed connection of overcoat outside stator module, rotates along with the rotor is together. The rotor has a magnet assembly surrounding the stator assembly. The coil 15 is used for realizing the change of magnetic poles by inputting variable current, and is matched with the magnet assembly to drive the rotor.

The circuit board 300 has a conductive portion. The conductive portion is provided on the substrate of the circuit board 300. The conductive portion protrudes from the periphery of the circuit board 300. The conductive portions may be electronic devices such as resistors, capacitors, etc. on the circuit board 300. The protective body covers the conductive portion and the peripheral portion. The protective member covers the conductive portion and the peripheral portion thereof, and the protective member for protection can be easily provided in a short time even for the three-dimensional conductive portion.

The protective body is in contact with the back surface of the circuit board 300 (the back surface of the circuit board 300 is a surface facing the lower stator holder 1, and the front surface is a surface facing away from the lower stator holder 1), and the protective body can extend from the front surface of the circuit board 300 to the back surface of the circuit board 300, thereby effectively suppressing the peeling from the circuit board 300.

Specifically, the stator bracket 1 is provided with a stator magnetic conductive bracket 100 and an insulating framework 200 for accommodating the stator magnetic conductive bracket 100. The insulating frame 200 is made of an insulating material such as plastic. The coil 15 is wound on the insulating bobbin 200. The circuit board 300 is fixed on the insulating frame 200. The (end surface of the) tooth end 104 is not accommodated by the insulating bobbin 200, but is exposed from the insulating bobbin 200. The protective body covers the circuit board 300 and provides a flat surface on the side facing away from the circuit board 300. Preferably, the circuit board 300 is covered inside the protection body.

In the present embodiment, the circuit board 300 is fixed to one end of the stator frame 1 in the axial direction in a manner perpendicular to the axial direction. The circuit board 300 is a ring-shaped circuit board 300, and a through hole is formed in the center of the circuit board for a motor shaft to pass through. The stator holder 1 (e.g., the insulating bobbin 200) has a positioning portion for positioning the circuit board 300. The circuit board 300 is positioned on the stator support 1 by relying on the positioning part, so that the circuit board 300 is conveniently coated by injection molding, and the circuit board 300 is prevented from shifting in the injection molding process.

Specifically, the stator frame 1 has slots, and the circuit board 300 has pins corresponding to the slots. As shown in fig. 5, the insulating frame 200 is provided with a positioning tube 280, and the positioning tube 280 is inserted into a through hole of the circuit board 300 to limit the circuit board 300, so as to prevent the circuit board 300 from rotating, and the circuit board 300 can be fixed by an anti-rotation pin. Or, stator support 1 or stator support 1's insulating skeleton 200 is equipped with the support arch, and circuit board 300 supports to be fixed a position on stator support 1's support arch to with stator support 1's base face (set up and support bellied surface) looks interval, the convenient hot melt adhesive injection in clearance between the two, promote the quality of moulding plastics, promote the solidification quality.

In other embodiments, the circuit board 300 is fixed on the outer side wall of the stator frame 1 in a manner parallel to the axial direction. The outer wall of the stator bracket 1 is provided with a positioning element such as a positioning insertion rod, and the circuit board 300 is pre-positioned by being clamped into a clamping groove of the circuit board 300, so that the circuit board 300 is prevented from shifting during injection molding.

With continued reference to fig. 1 to 6, in the present embodiment, the protective body has an adhesive portion filled between the circuit board 300 and the stator frame 1. The bonding portion has the face of bonding that bonds circuit board 300 and stator support 1 respectively to this fixes bonding circuit board 300 on stator support 1, realizes the zonulae occludens of the two, simultaneously, the bonding portion is filled between circuit board 300 and stator support 1, avoids having into the clearance of water dust intake between the two, promotes the insulation protection between circuit board 300 and the stator support 1.

The insulating frame 200 has a first frame 210 and a second frame 220 that are engaged with the two sides of the stator magnetic conductive bracket 100 in an axial direction. The first frame 210 and the second frame 220 are made of plastic. The first framework 210 is disposed at the upper end of the stator magnetic conductive support 100, and the second framework 220 is fixedly disposed at the other end of the stator magnetic conductive support 100 along the axial direction. The first and second support portions are relatively buckled at two axial ends of the stator magnetic conductive bracket 100 to surround the outer convex portions 103, so as to form the stator teeth 231 of the stator bracket 1. A first framework 210 is fixedly arranged at one axial end (upper end) of the stator magnetic conduction bracket 100. The circuit board 300 is fixed to the first frame 210.

The insulating frame 200 is formed by relying on the stator magnetic conduction bracket 100. The first frame 210 and the second frame 220 have an insertion portion 211 and a flat portion 212, respectively. The flat portions 212 are fitted on the surfaces of the convex portions 103, and the protruding portions 211 on both sides protrude into the inner groove 105 between the convex portions 103. The insulating frame 200 (the first frame 210) further has a positioning tube 280 at the center, and the circuit board 300 is fixedly sleeved outside the positioning tube 280. The protruding portion 211 has a slot hole 213 for winding the coil 15.

In this embodiment, the insulator 2 further includes a filling portion filled between the insulating bobbin 200 and the stator magnetic conductive bracket 100. Through being equipped with the filling portion, this stator module has better anti falling performance when carrying out the drop test. The filling part is close to the insulating framework 200 in material, so that the adhesive property is better, the bonding stability of the insulator 2 and the stator support 1 is improved, the matching degree of the insulating framework 200 and the stator magnetic conduction support 100 (such as an iron core) can also be improved, and the anti-falling and waterproof properties and the adaptability of different scenes are improved. Through being equipped with insulating skeleton 200, can avoid coil 15 direct coiling on stator magnetic conduction support 100 and by the metal fish tail, and then coil 15 obtains the protection, guarantees the life of product.

In a specific embodiment, as shown in fig. 6, 7 and 8, the stator frame 1 includes a magnetic conductive coil body 100 and an insulating bobbin 200 fixed inside the magnetic conductive coil body 100. The insulating bobbin 200 provides a plurality of stator teeth 231 around which the coil 15 is wound. The stator teeth 231 extend radially from the outside to the inside. The inner end surfaces of the stator teeth 231 face radially inward. The insulator 2 extends radially inward from the magnetic conductive ring body 100 to the inner end surface. The magnetic conductive ring body 100 may further include a plurality of heat dissipation holes 140.

In the present embodiment, the stator teeth 231 may have a hollow structure. The stator teeth 231 have center holes, and the insulator 2 has a filling portion filled in the center holes of the stator teeth 231. The inner surfaces of the filling part and the insulating spacer part 20 are located at substantially the same radial position as the inner end surfaces of the tooth ends 104 of the stator teeth 231, and form the inner wall of the central through hole 500, surrounding the central through hole 500. Through more packing, realize the inseparable bonding between the material, reach better structural stability and better waterproof prevent falling performance.

Of course, in the embodiment shown in fig. 9 and 10, the stator teeth 231 have no central hole, and the insulator 2 is only filled in the periphery of the stator teeth 231 and the coil 15, and is not filled in the interior of the stator teeth 231. The insulation spacers 20 extend in the axial direction on both sides of the inner end surfaces of the stator teeth 231, and are continuous in the circumferential direction at both axial ends of the stator teeth 231, thereby surrounding the inner end surfaces of the stator teeth 231.

With reference to fig. 6, 7 and 8, the insulating frame 200 is fixedly sleeved in the magnetic conductive ring body 100. The magnetic conductive ring body 100 is made of a magnetic conductive material, and the magnetic conductive ring body 100 is a magnetic conductive ring to close the magnetic circuit. The magnetic conductive ring body 100 is sleeved outside the insulating framework 200. The insulator 2 has an outer adhesive surface to which the magnetic conductive coil body 100 is hermetically bonded. The insulator 2 extends radially inward from the outer bonding surface to the outer surface of the tooth tip 104, completely covering the coil 15.

The insulator 2 coats the insulating framework 200 and provides a bonding surface with the magnetic conductive ring body 100, so that the assembling degree of the insulating framework 200 and the magnetic conductive ring body 100 is improved, the insulating framework 200 is prevented from falling off, and the structural stability of the equipment is improved. Therefore, the coil 15 can be wound on the insulating framework 200 in advance, the magnetic conductive coil body 100 is sleeved outside the insulating framework 200, and finally the magnetic conductive coil body 100, the insulating framework 200 and the coil 15 are integrally fixed by placing the magnetic conductive coil body 100 in a mold and performing low-pressure injection molding to form the insulator 2.

In the present embodiment, the stator frame 1 has stator teeth 231 surrounded by the coil 15. The insulator 2 covers the coil 15 inside, and the inner end surfaces of the stator teeth 231 in the radial direction are not covered with the insulator 2 to be exposed. The inner end surface of the stator tooth 231 in the radial direction and the inner wall of the insulator 2 participate in forming the inner wall surface of the central through hole 500, so as to form an inner magnetic conductive wall surface 1011. The inner wall of the insulator 2 and the outer surface of the stator tooth 231 not covered by the insulator 2 are substantially on the same cylindrical surface, and inner insulating ring portions 22 are formed on both axial sides of the inner magnetically permeable wall surface 1011, or an intermediate insulating ring portion 25 is formed between the inner magnetically permeable wall surfaces 1011 on both axial sides.

The insulator 2 has an insulating inner wall continuously extending in the circumferential direction on the radially inner side of the coil 15 and the stator teeth 231. The insulating inner wall is disposed around a central through hole 500. The insulator 2 covers the plurality of coils 15 and the plurality of stator teeth 231. The outer side wall of the insulator 2 has an annular receiving groove 230 depressed inward in the radial direction; the outer ring body is at least partially annularly sleeved in the annular accommodating groove 230 and is hermetically bonded with the insulator 2. The insulator 2 is provided with an adhesive surface which is hermetically adhered with the outer ring body; the bonding surface extends continuously in the circumferential direction.

The inner wall of the insulator 2 and the (innermost) surface of the tooth end 104 of the stator tooth 231 not covered by the insulator 2 participate in forming the inner wall surface of the central through hole 500. The inner wall (insulation spacer 20) of the insulator 2 and the inner surface of the tooth tip 104 constitute an inner surface continuously extending in the circumferential direction, surrounding the central through hole 500 forming the stator assembly.

An embodiment of the present invention also provides a brushless motor including a stator assembly according to any one of the above aspects. The brushless motor is provided with a motor shaft, the motor shaft is rotatably sleeved in the stator assembly and penetrates the circuit board, and two ends of the motor shaft extend out of the stator assembly.

An embodiment of the present invention further provides a method for manufacturing a stator assembly of a brushless motor, including the steps of: s100, placing the stator support 1 wound with the plurality of coils 15 into a cavity of a mold; and S200, injecting hot melt adhesive in a molten state into the cavity through low-pressure injection molding equipment, wherein the hot melt adhesive is solidified to form an insulator 2 which coats the coils 15 and forms an insulating interval part 20 between every two adjacent coils 15.

In step S100, the inner wall of the stator frame 1 is fitted and sleeved outside a filling rod. The cavity provides glue injection space at least outside the coil 15. The cavity also provides a glue solution injection space outside the stator support 1, and correspondingly, the coil 15 and the stator support 1 are coated after the hot melt glue is solidified. The cavity at least accommodates a plurality of the coils 15 and provides a glue injection space surrounding the coils 15 outside the coils 15.

The manufacturing method further comprises the steps of: s50, the circuit board 300 is fixed to the stator frame 1. Correspondingly, the manufacturing method comprises the following steps: s101, placing the stator support 1 wound with the plurality of coils 15 and the circuit board 300 into a cavity of a mold; s201, injecting a molten hot melt adhesive into the cavity, and after the hot melt adhesive is solidified, forming the insulator 2 covering the plurality of coils 15 and the protector covering at least a part of the circuit board 300.

Further, the cavity provides a glue injection space for injecting the glue surrounded by the stator frame 1 wound with the plurality of coils 15 and the circuit board 300. Correspondingly, the manufacturing method comprises the following steps: and injecting a molten hot melt adhesive into the cavity, and solidifying the hot melt adhesive to form an external shell which coats the stator support 1 wound with the plurality of coils 15 and the circuit board 300.

A mold for low-pressure injection molding is prepared, and a pre-assembled assembly (including the coil 15, the stator frame 1, and the circuit board 300 which have been assembled in advance in predetermined positions) can be disposed and carried in a cavity of the mold. The cavity of the mould is empty when the pre-assembled component is placed in, the space corresponding to the shape of the insulator 2. For example, the inner wall of the stator frame 1 fits around a filling rod, so that the inner surface of the stator teeth 231 of the stator frame 1 cannot be covered by the insulator 2 and is exposed after molding. After the injection molding, the stator assembly in which the insulator 2 and the protector are integrally molded is taken out of the mold after a predetermined cooling time has elapsed.

Any numerical value recited herein includes all values from the lower value to the upper value that are incremented by one unit, provided that there is a separation of at least two units between any lower value and any higher value. For example, if it is stated that the number of a component or a value of a process variable (e.g., temperature, pressure, time, etc.) is from 1 to 90, preferably from 20 to 80, and more preferably from 30 to 70, it is intended that equivalents such as 15 to 85, 22 to 68, 43 to 51, 30 to 32 are also expressly enumerated in this specification. For values less than 1, one unit is suitably considered to be 0.0001, 0.001, 0.01, 0.1. These are only examples of what is intended to be explicitly recited, and all possible combinations of numerical values between the lowest value and the highest value that are explicitly recited in the specification in a similar manner are to be considered.

Unless otherwise indicated, all ranges include the endpoints and all numbers between the endpoints. The use of "about" or "approximately" with a range applies to both endpoints of the range. Thus, "about 20 to about 30" is intended to cover "about 20 to about 30", including at least the endpoints specified.

All articles and references disclosed, including patent applications and publications, are hereby incorporated by reference for all purposes. The term "consisting essentially of …" describing a combination shall include the identified element, ingredient, component or step as well as other elements, ingredients, components or steps that do not materially affect the basic novel characteristics of the combination. The use of the terms "comprising" or "including" to describe combinations of elements, components, or steps herein also contemplates embodiments that consist essentially of such elements, components, or steps. By using the term "may" herein, it is intended to indicate that any of the described attributes that "may" include are optional.

A plurality of elements, components, parts or steps can be provided by a single integrated element, component, part or step. Alternatively, a single integrated element, component, part or step may be divided into separate plural elements, components, parts or steps. The disclosure of "a" or "an" to describe an element, ingredient, component or step is not intended to foreclose other elements, ingredients, components or steps.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the present teachings should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are hereby incorporated by reference for all purposes. The omission in the foregoing claims of any aspect of subject matter that is disclosed herein is not intended to forego such subject matter, nor should the inventors be construed as having contemplated such subject matter as being part of the disclosed subject matter.

Claims

1. A stator assembly of a brushless electric machine, comprising:

a stator support;

2. The stator assembly of claim 1 wherein the insulator extends continuously in a circumferential direction.

3. The stator assembly of claim 1 wherein said stator assembly has a central throughbore; the inner wall of the stator frame is not covered by the insulator; the inner wall of the stator holder and the inner wall of the insulator constitute an inner wall of the central through hole extending continuously in the circumferential direction.

4. The stator assembly of claim 1, wherein the stator frame has stator teeth surrounded by the coils; the insulator covers the coil inside, and inner end faces of the stator teeth in the radial direction are not covered with the insulator to be exposed.

5. The stator assembly of claim 4 wherein said stator assembly has a central throughbore; the inner end surfaces of the stator teeth in the radial direction and the inner wall of the insulator participate in forming the inner wall surface of the central through hole.

6. The stator assembly of claim 4 wherein said stator frame has a magnetic conductive ring body and an insulating skeleton secured to an inner side of said magnetic conductive ring body; the insulating framework is provided with a plurality of stator teeth for winding the coil, and inner end surfaces of the stator teeth face to the inner side in the radial direction; the insulator extends inwards from the magnetic conductive ring body to the inner end surface in the radial direction.

7. The stator assembly of claim 1, wherein the stator frame has stator teeth surrounded by the coils; the insulator covers the coil inside, and the outer end faces of the stator teeth in the radial direction are not covered with the insulator to be exposed.

8. The stator assembly of claim 7, wherein the stator frame further has an inner ring body; the plurality of stator teeth are uniformly and fixedly arranged on the outer side of the inner ring body along the circumferential direction; the stator teeth extend radially outward from the inner ring body; the outer end faces of the stator teeth and the outer wall face of the insulator are approximately on the same cylindrical surface.

9. The stator assembly of claim 8 wherein the outer end faces of the stator teeth and the outer wall surface of the insulator form an outer wall surface of the stator assembly that extends continuously in a circumferential direction.

10. The stator assembly of claim 8 further comprising a circuit board fixedly disposed on the stator frame; the circuit board is electrically connected with the coil; at least a part of the circuit board is covered by a protective body made of hot melt adhesive molded by low-temperature and low-pressure injection molding.

11. The stator assembly of claim 10 wherein said stator support is provided with a stator magnetically permeable support and an insulating skeleton housing said stator magnetically permeable support; the coil is wound on the insulating framework; the circuit board is fixed on the insulating framework.

12. The stator assembly of claim 11 wherein said insulator further has a filler filled between said insulating skeleton and said stator magnetically permeable support.

13. The stator assembly of claim 10 wherein the protective body and the insulator are of unitary injection molded construction.

14. A brushless electric machine comprising a stator assembly according to any of claims 1-13.

15. A method of manufacturing a stator assembly of a brushless motor, comprising the steps of:

16. The manufacturing method according to claim 15, wherein the cavity further provides a glue injection space outside the stator frame, and accordingly, the hot melt glue coats the coil and the stator frame after being cured.

17. The method of manufacturing of claim 15, further comprising the step of: fixedly assembling the circuit board on the stator bracket;

the manufacturing method comprises the following steps:

18. The manufacturing method according to claim 15, wherein the cavity provides a glue injection space that surrounds the stator frame wound with the plurality of coils and the circuit board; the manufacturing method comprises the following steps: and injecting a molten hot melt adhesive into the cavity, and forming an external shell which coats the stator support wound with the plurality of coils and the circuit board inside after the hot melt adhesive is solidified.