CN115621755A

CN115621755A - Connection structure for brushless motor and brushless motor

Info

Publication number: CN115621755A
Application number: CN202211406556.1A
Authority: CN
Inventors: 陈亮; 谢小五; 张宏亮; 江远
Original assignee: Guangdong Zhaoqing L&V Co Ltd
Current assignee: Guangdong Zhaoqing L&V Co Ltd
Priority date: 2022-11-10
Filing date: 2022-11-10
Publication date: 2023-01-17
Also published as: WO2024099317A1

Abstract

The present invention relates to a connection structure for a brushless motor, the brushless motor including a stator assembly and a rotor assembly, the stator assembly including a stator and a stator winding, the stator winding being electrically connected with a PCB board at one axial end to achieve power transmission via the PCB board, the connection structure including a first contact section and a second contact section, the first contact section being intended to be in electrical contact with a coil of the stator winding, the second contact section being intended to be in electrical contact with the PCB board so that electrical connection between the stator winding and the PCB board can be achieved via the connection structure, the first contact section including a breaking portion for breaking an insulating sheath of the coil and a clamping portion for clamping and holding a metal wire of the coil. The invention also relates to a brushless motor comprising the connecting structure. In a motor structure with a smaller size, the connection structure solves the circuit connection problem of the motor under the condition that the soldering process cannot be carried out due to limited space, saves the process and labor, and is easier for automatic production.

Description

Connection structure for brushless motor and brushless motor

Technical Field

The invention relates to the technical field of motors, in particular to a connecting structure for a brushless motor and the brushless motor comprising the connecting structure.

Background

With the development of scientific technology, more and more functions are integrated in automobiles in order to meet the needs of automobile users as much as possible and to improve the use comfort of the users. In order to achieve these functions, electric motors, in particular brushless dc motors, are widely used in the automotive field.

A brushless motor generally includes a stator assembly including a stator and a stator winding wound on the stator, the stator winding being electrically connected to a PCB board to transmit power to the motor. In the existing brushless motor design, especially in the motor structure with smaller size, the enameled wire of the stator winding and the PCB are connected through manual soldering tin to ensure the circuit communication.

However, when the motor is required to be designed to have a very small size, there are often problems in that: after the PCB is mounted, there is often no space for a soldering iron to enter for performing soldering or the soldering process cannot be conveniently operated, limited by the size design of the motor; or, when the motor working current is relatively large, the wire diameter of the enameled wire of the winding is relatively large, so that soldering on the PCB is difficult to implement. In addition, because manual soldering is often required in the prior art, human resources account for a certain proportion, the process is relatively complex, the production efficiency is low, and the automatic production is difficult to realize.

Accordingly, there is a need for a new brushless motor structure that overcomes one or more of the problems set forth above and/or other deficiencies in the prior art.

Disclosure of Invention

The present invention has been made in view of such background. According to an aspect of the present invention, there is provided a connection structure for a brushless motor including a stator assembly including a stator and a stator winding wound on the stator, the stator winding being electrically connected at one axial end with a PCB board to enable power transmission via the PCB board, the connection structure including a first contact section intended to electrically contact with a coil of the stator winding and a second contact section intended to electrically contact with the PCB board so that electrical connection between the stator winding and the PCB board can be achieved via the connection structure, wherein the first contact section includes a breaking portion for breaking an insulating sheath of the coil and a clamping portion for clamping and holding a metal wire of the coil.

Advantageously, the connecting structure further comprises an intermediate section for connecting the first and second contact sections, the outermost edge of the intermediate section extending beyond the first contact section.

Advantageously, the first contact section comprises two contact arms arranged spaced apart from each other, between which a space is defined through which the coil passes.

Advantageously, a pair of first projections are oppositely provided on the inner edges of the two contact arms facing each other, with a first width defined therebetween, which is smaller than the outer diameter of the coil, so that the coil is pierced with the insulating sheath by the pair of first projections when entering into the space.

Advantageously, a pair of second projections are oppositely provided on inner edges of the two contact arms facing each other, a second width being defined between the pair of second projections, the second width being smaller than the first width, so that the metal wire of the coil is clamped and held by the pair of second projections.

Advantageously, a pair of third projections is provided on the first contact section, the third projections being intended to be in interference fit with receiving grooves for receiving the first contact section.

Advantageously, the second contact section is formed in the form of a fisheye pin adapted to be press-fitted with a pre-made tinning hole in the PCB board.

According to another aspect of the present invention, there is provided a brushless motor including a plurality of the above-described coupling structures.

Advantageously, the brushless motor comprises a plurality of insulating sleeves provided at the axial ends of the stator winding, on each of which a receiving slot is opened through which a portion of the coil of the stator winding passes.

Advantageously, the first contact section of the connection structure is intended to be press-fitted in the corresponding receiving groove, so that during the pressing-in process the insulating sheath of the coil is pierced by the wire-breaking portion and the metal wire of the coil is clamped and held by the clamping portion.

Compared with the prior art, the connecting structure for the brushless motor and the brushless motor comprising the connecting structure can achieve at least one of the following technical effects: the reliable circuit connection mode between the winding coil and the PCB can be provided under the condition that the soldering procedure cannot be realized or is inconvenient to implement due to the limited size and space of the motor; the reliable connection of the circuit can be realized, and the structure requirements of different working current sizes can be met; the soldering process between the coil (such as a varnished wire) and the PCB is omitted, the operability is good, the process is relatively simple, and the automatic production is easy.

Drawings

The above and other features and advantages of the present invention will become more readily appreciated from the following description taken in conjunction with the accompanying drawings, in which:

fig. 1 is a schematic structural view showing a connection structure for a brushless motor according to the present invention;

fig. 2a shows a schematic perspective view of a brushless motor (on which no PCB board is mounted) according to the present invention; fig. 2b shows a schematic perspective view of a brushless motor (with a PCB board mounted thereon) according to the present invention;

fig. 3a shows, in a sectional view, in part, an insulating sleeve provided at one axial end of a winding of the brushless motor shown in fig. 2a and 2 b; FIG. 3b shows a schematic view of the connection structure shown in FIG. 1 as press-fitted into an insulating sleeve; and

fig. 4 shows the clamping relationship between the winding coil and the connection structure.

All the figures are purely diagrammatic and not drawn to scale, and moreover they show only those parts which are necessary in order to elucidate the invention, other parts being omitted or merely mentioned. That is, the present invention may include other components in addition to those shown in the drawings.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention to those of ordinary skill in the art. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without some of these specific details. The following aspects, features, embodiments and advantages are merely illustrative and should not be considered elements or limitations of the claims except where explicitly recited in a claim. Terms such as "first," "second," and the like are used hereinafter to describe elements of the present application and are used only to distinguish one element from another without limiting the nature, sequence, order, or number of such elements. In addition, it is to be noted that in the present description, identical and/or functionally identical technical features are provided with the same or similar reference signs.

The motor can be classified into a direct current motor and an alternating current motor according to the type of a working power supply, wherein the direct current motor generally comprises a brush direct current motor and a brushless direct current motor, wherein the brush direct current motor adopts mechanical commutation, an external magnetic pole is fixed, an internal coil is movable, when the motor works, a commutator and the coil rotate together, a carbon brush and magnetic steel are not movable, and then the commutator and the carbon brush generate friction to complete current direction switching; the brushless DC motor is electronically commutated without commutator and carbon brush, and is composed of permanent magnet rotor, multi-pole winding stator, position sensor, etc. the position sensor energizes adjacent stator coil according to the position of magnetic pole of rotor, and the stator generates magnetic pole attracted with rotor to attract rotor to rotate, so repeating to drive motor to rotate.

The coupling structure according to the present invention, which will be discussed in detail below, is mainly applied to a brushless motor. The stator windings of a brushless motor are typically three-phase windings. To achieve power transmission of the motor, the stator windings electrically connect the coils of each phase winding with the PCB board at one of the axial ends. In the existing brushless motor design, especially in the motor structure with smaller size, the coil of the stator winding in the form of the enameled wire is connected with the PCB board through manual soldering to ensure the circuit connection. As mentioned in the background section, due to the limited dimensional space of the motor, there are often situations where the soldering process is not possible or inconvenient to implement, which makes a reliable and efficient way to implement the electrical connections of the motor necessary.

To this end, the present invention proposes an improved structure relating to a connection structure for windings of a brushless motor, in particular, which can reliably achieve circuit connection of the motor without performing a soldering process.

In particular, as shown in fig. 1, the connection structure 100 may be formed in the form of a metal connecting piece (e.g., a copper sheet material of C19010 or similar tin bronze, etc.) comprising a first contact section 110, a second contact section 120, and an intermediate section 130 for connecting the first contact section 110 and the second contact section 120. The first contact section 110 is intended to be in electrical contact with a coil 400 of a stator winding and the second contact section 120 is intended to be in electrical contact with the PCB board 200, such that an electrical connection between the stator winding and the PCB board 200 can be achieved via the connection structure 100.

Different from the prior art, the connection structure 100 of the present invention can eliminate the soldering process between the winding coil and the PCB. In particular, the first contact section 110 advantageously comprises a wire breaking portion for piercing the insulating sheath of the coil and a clamping portion for clamping and holding the bare metal wire of the coil. In this manner, during pressing the connecting structure 100 into, for example, the insulating sheath 300 (which is opened with the receiving groove 301, see fig. 3 a) formed at the axial end of the stator winding, the insulating sheath of the coil will first be pierced by the broken wire portion, and the exposed metal conductive wire (e.g., copper wire) will be finally clamped and held by the clamping portion. The wire breaking portion and the clamping portion may have various different structural forms as long as the above-described functions can be achieved.

According to the exemplary embodiment as shown in fig. 1, the first contact section 110 comprises two contact arms 111 spaced apart from each other and preferably symmetrically arranged, the two contact arms 111 extending from the intermediate section 130 in a direction away from the second contact section 120, and a space 112 is defined between the two contact arms 111 through which the winding coil passes. A pair of first protrusions 111a are oppositely or symmetrically provided on inner edges of the two contact arms facing each other, and a first width W1 is defined between the pair of first protrusions 111a, the first width W1 being smaller than an outer diameter of the coil, such that an insulating sheath of the coil is pierced by the pair of first protrusions 111a when the corresponding coil is initially pressed into the space 112.

In addition, as the coil is continuously pressed into the space 112 with respect to the two contact arms 111, the metal wire of the coil, which has been punctured, will be pinched by a pair of second protrusions 111b oppositely or symmetrically disposed on the inner edges of the two contact arms 111 facing each other. Specifically, a second width W2 is defined between the pair of second protrusions 111b, and the second width W2 is smaller than the outer diameter of the coil and the first width W1, thereby allowing the metal wire of the coil to be clamped and held by the pair of second protrusions 111b (see fig. 4).

Preferably, the second contact section 120 may be formed in the form of a fisheye pin (see fig. 1) adapted to be press-fitted with a pre-made tinning hole 201 (see fig. 2 b) in said PCB board 200. Thus, the winding coil and the PCB can be electrically connected through the connecting structure, and the complicated soldering process between the winding coil and the PCB is not needed.

In the case of a stator winding employing a three-phase winding, there may be provided at least three connection structures 100, wherein the brushless motor may include a plurality of insulation sleeves 300 disposed at the axial ends of the stator winding, and the insulation sleeves 300 may be integrally formed or separately formed. Receiving slots 301 are formed in the insulating sheath 300, and a portion of the coil of the corresponding phase winding of the stator winding passes through one of the receiving slots 301.

Referring particularly to fig. 3b, the first contact section 110 of the connecting structure 100 is intended to be press-fitted in the receiving groove 301 of said insulating sleeve 300. As the first contact section 110 is pressed inward toward the receiving groove 301, the insulating sheath of the coil 400 will be pierced by the wire-breaking portion (the first protrusion 111 a), and the exposed metal wire is then clamped and held by the clamping portion (the second protrusion 111 b).

Since the outermost edge of the intermediate section 130 of the connecting structure is designed to extend beyond the first contact section 110, the lower edge 131 of the intermediate section 130 will stop against the insulating sleeve 300 when the pressing-in process is completed.

In order to enable the connection structure 100 to be stably held in the receiving groove 301, a pair of third protrusions 111c may be further provided on the first contact section 110. In particular, on the outer edges of the two contact arms 111 remote from each other, a third projection in the form of a pair of barbs defining a third width W3 which is greater than the inner hole diameter of the receiving groove 301 (see fig. 3 b), in such a way as to ensure that the connection structure 100 can be interference-fitted in the receiving groove 301 by means of said third projection.

In this way, the connecting structure not only can pierce the insulating sheath by the pressing action, but also can be stably held in the receiving groove under the condition of ensuring the electric contact between the connecting structure and the exposed metal lead wire, and meanwhile, the second contact section is pressed on the PCB and is electrically connected with the PCB, so that the welding procedure is replaced by simple operation steps, and the circuit connection of the motor is reliably realized.

It will be appreciated by those skilled in the art that the three-phase stator windings may be star-connected and delta-connected. A brushless motor with star-connected windings is shown in fig. 2a-2 b. In this brushless motor, three connection structures 100 discussed above are provided, which are inserted into receiving grooves of correspondingly provided insulating bushes and are in electrical contact with coils of corresponding phase windings passing through the receiving grooves, respectively. In addition, in order to achieve a star connection of the windings, a similar connection structure 100' (see fig. 2 a) may advantageously also be provided to achieve a common terminal connection of the three-phase windings. Such a connection structure 100' may also include similar wire breakage portions and clamping portions at each of the terminals electrically connected to the winding coil, as in the aforementioned connection structure 100, so that the common terminal welding process can be omitted. If the connection structure 100' is required to be used with the PCB 200, a fish-eye pin may be formed thereon to facilitate electrical connection of the PCB.

As an improvement point of the present invention, since the connection structure of the present invention does not depend on the soldering process to realize the circuit connection between the winding and the PCB, it is possible to use various sizes of motor operating currents without considering the influence of the diameter of the enamel wire on the soldering process.

The width a of the second contact section 120, e.g. a fish-eye pin, in the connection according to the invention can be selected according to the magnitude of the operating current of the motor, thereby allowing adaptation to the structural requirements of different magnitudes of operating current. Accordingly, the size of the pre-plated holes 201 on the PCB 200 intended to mate with the fisheye pins may be selected according to the width a to ensure a press-fit relationship between the two.

When the connecting structure is pressed into the accommodating groove of the insulating sleeve, the wire breaking part punctures the insulating outer skin of the coil and the clamping part clamps and stably keeps the metal conducting wire of the coil, so that the soldering process between the winding coil of the brushless motor and the PCB can be replaced.

It should be noted that the above-described embodiments should be regarded as merely illustrative, and the present invention is not limited to these embodiments. Various changes and modifications may be made by those skilled in the art without departing from the scope or spirit of the invention in view of the contents of this specification. With a true scope of the invention being indicated by the following claims and their equivalents.

Claims

1. A connection structure (100) for a brushless motor including a stator assembly including a stator and a stator winding wound on the stator, the stator winding being electrically connected at one axial end with a PCB board (200) to enable power transmission via the PCB board, characterized in that the connection structure (100) includes a first contact section (110) intended to be in electrical contact with a coil (400) of the stator winding and a second contact section (120) intended to be in electrical contact with the PCB board (200) so that electrical connection between the stator winding and the PCB board can be achieved via the connection structure, wherein the first contact section (110) includes a breaking portion for breaking an insulation sheath of the coil (400) and a clamping portion for clamping and holding a metal wire of the coil (400).

2. The connection structure (100) according to claim 1, further comprising an intermediate section (130) for connecting the first contact section (110) with the second contact section (120), the outermost edge of the intermediate section exceeding the first contact section.

3. The connection structure (100) according to claim 1, wherein the first contact section (110) comprises two contact arms (111) arranged spaced apart from each other, between which a space (112) is defined through which the coil passes.

4. The connection structure (100) according to claim 3, wherein a pair of first protrusions (111 a) are oppositely disposed on inner edges of the two contact arms (111) facing each other, with a first width (W1) defined therebetween, which is smaller than an outer diameter of the coil, so that the coil is pierced with the insulating sheath by the pair of first protrusions (111 a) when entering into the space (112).

5. The connection structure (100) according to claim 4, wherein a pair of second protrusions (111 b) are oppositely provided on inner edges of the two contact arms (111) facing each other, a second width (W2) being defined between the pair of second protrusions, the second width being smaller than the first width, so that the metal wire of the coil is clamped and held by the pair of second protrusions (111 b).

6. The connection structure (100) according to any one of claims 1 to 5, characterised in that a pair of third projections (111 c) are provided on the first contact section (110), the third projections being intended for an interference fit with a receiving groove (301) for receiving the first contact section.

7. The connection arrangement (100) according to any one of claims 1 to 5, characterised in that the second contact section (120) is formed in the form of a fisheye pin adapted to be press-fitted with a pre-made tinning hole (201) on the PCB board (200).

8. A brushless electric machine, characterized in that it comprises a plurality of connection structures (100) according to any one of claims 1 to 7.

9. The brushless electric machine according to claim 8, comprising a plurality of insulating sleeves (300) provided at the axial ends of the stator windings, on each of which a receiving slot (301) is opened through which a portion of a coil of the stator winding passes.

10. The brushless electric machine according to claim 9, characterized in that the first contact section (110) of each connection structure (100) is intended to be press-fitted in the respective receiving groove (301) such that during the pressing-in process the insulating sheath of the coil is pierced by the wire breaking portion and the metal wire of the coil is clamped and held by the clamping portion.