CN212627378U

CN212627378U - Electric device, brushless direct current motor and stator thereof

Info

Publication number: CN212627378U
Application number: CN202020906851.3U
Authority: CN
Inventors: 雷远河; 曾棕湋; 田原; 王万友
Original assignee: Johnson Electric International AG
Current assignee: Johnson Electric International AG
Priority date: 2020-05-26
Filing date: 2020-05-26
Publication date: 2021-02-26
Anticipated expiration: 2030-05-26
Also published as: WO2021238295A1

Abstract

The utility model relates to an electronic technical field provides an electric actuator, brushless DC motor and stator thereof. A stator for a brushless DC motor includes: stator core, fixing last bobbin of stator core to and by the electromagnetic wire around locating the last stator winding that forms of bobbin, bobbin includes to support by the backstop board of a stator core axial end, from the line portion of crossing that the backstop board upwards extends, and certainly the wrapping post of backstop board downwardly extending, cross the line portion including certainly the basal portion that the backstop board extends, and set up a plurality of conductive terminals on the basal portion, a plurality of conductive terminals are divided into the multiunit, and every group includes two at least conductive terminals, belongs to through electromagnetic wire lug connection between the conductive terminal of same group. The utility model provides a stator, convenient assembling, simple process and reliability are high to manufacturing cost has been reduced effectively.

Description

Electric device, brushless direct current motor and stator thereof

Technical Field

The utility model relates to an electronic technical field especially relates to a brushless DC motor that electric actuator, this electric actuator used and this brushless DC motor's stator.

Background

In a brushless dc motor, it is necessary to electrically connect the windings of the stator to each phase of an external power supply to control the commutation of the power supplied to the windings by the circuit of the controller. The stator windings of conventional brushless dc motors usually have a three-phase symmetrical star connection and a delta connection. The existing stator winding is generally led out by pulling out the wire ends of the three-phase winding and then connecting the wire ends together by terminal crimping or welding. However, since there are many wire ends, insulation protection is required one by one, and the process is complicated and has poor reliability, and the terminal is easily broken. In addition, in order to reduce the number of wire ends, the conventional winding frame combines three layers of ring-shaped terminals together by adopting secondary coating molding. However, this results in excessive processing costs and cumbersome processing.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present invention aims to provide a stator that can solve or at least reduce the above problems, and a brushless dc motor having the stator and an electric device having the brushless dc motor.

Therefore, the utility model provides a stator for brushless DC motor, include: stator core, fixing last bobbin of stator core to and by the electromagnetic wire around locating the last stator winding that forms of bobbin, bobbin includes to support by the backstop board of a stator core axial end, from the line portion of crossing that the backstop board upwards extends, and certainly the wrapping post of backstop board downwardly extending, cross the line portion including certainly the basal portion that the backstop board extends, and set up a plurality of conductive terminals on the basal portion, a plurality of conductive terminals are divided into the multiunit, and every group includes two at least conductive terminals, belongs to through electromagnetic wire lug connection between the conductive terminal of same group.

In some embodiments, the plurality of conductive terminals are evenly spaced along a circumference of the base.

In some embodiments, the bobbin further includes a plurality of flange portions extending radially outward from an outer periphery of the base portion, the plurality of flange portions being spaced circumferentially of the bobbin and circumferentially offset from the plurality of conductive terminals.

In some embodiments, each of the plurality of flanges forms at least one receiving slot for receiving a magnet wire.

In some embodiments, each of the plurality of flange portions includes a first protruding rib, a second protruding rib, and a third protruding rib sequentially arranged from top to bottom along the axial direction, a first receiving groove is formed between the first protruding rib and the second protruding rib, a second receiving groove is formed between the second protruding rib and the third protruding rib, a third receiving groove is formed between the third protruding rib and the stop plate, the first receiving groove, the second receiving groove, and the third receiving groove respectively receive U, V, W three-phase electromagnetic wires, and each receiving groove has an inclined surface where the corresponding electromagnetic wire is bent from the corresponding conductive terminal to enter the receiving groove.

In some embodiments, the stator winding is a delta winding formed by winding a magnet wire, and the plurality of sets of conductive terminals are also connected by the magnet wire.

In some embodiments, the plurality of conductive terminals includes three first terminals and a plurality of second terminals, each of the first terminals includes a first body secured to the base, a first terminal pin located radially outward of the first body, and a post extending axially from the first body, and each of the second terminals includes a second body secured to the base and a first terminal pin located radially outward of the second body.

In some embodiments, the three first terminals are adjacently arranged along the circumferential direction of the base, the three first terminals and the plurality of second terminals are sequentially and repeatedly arranged in the circumferential direction of the base in the order of U, V, W phase terminals, the stator core includes a plurality of pole teeth having the same number as the plurality of conductive terminals, and the windings on the plurality of pole teeth are in one-to-one correspondence with the plurality of conductive terminals.

Furthermore, the utility model also provides a brushless DC motor, including rotor and above-mentioned stator, the rotor accept in the stator, the rotor can for the stator rotates.

The utility model also provides an electric actuator, including above-mentioned brushless DC motor.

The embodiment of the utility model provides a stator, convenient assembling, simple process and reliability are high to manufacturing cost has been reduced effectively.

Drawings

Fig. 1 is a perspective view of a brushless dc motor according to an embodiment of the present invention, in which a casing of the brushless dc motor is omitted.

Fig. 2 shows an axial cross-section of the brushless dc motor shown in fig. 1.

Fig. 3 shows a perspective view of a stator of the brushless dc motor shown in fig. 1.

Fig. 4 is a perspective view showing a bobbin of the brushless dc motor shown in fig. 1, around which electromagnetic wires are wound.

Fig. 5 is a perspective view showing a first bobbin of the bobbin shown in fig. 4, around which an electromagnetic wire is wound.

Fig. 6 shows a perspective axial cross-sectional view of a first bobbin of the bobbin shown in fig. 4.

Fig. 7a shows a plan view of the stator of the brushless dc motor shown in fig. 1.

Fig. 7b shows a schematic view of the stator windings of the brushless dc motor shown in fig. 1.

Fig. 8 shows a schematic diagram of a stator winding of a brushless dc motor according to another embodiment of the present invention.

Fig. 9 shows a schematic view of an electric device according to an embodiment of the present invention.

Fig. 10 shows a schematic view of an electric device according to another embodiment of the present invention.

Reference numerals: 100-a brushless dc motor; 10-a stator; 11-a stator core; 110-yoke; 111-pole teeth; 12-winding framework; 120-a first skeleton; 121-a first stop plate; 129-a wire passing part; 122-a base; 220-a flange portion; 221-a first rib; 222-a second rib; 223-a third rib; 224-a first receiving groove; 225-a second receiving groove; 226-third receiving groove; 227-a first bevel; 228-a second bevel; 229-a third bevel; 123-a first winding post; 124-a fixed part; 241-opening; 25-a conductive terminal; 125-a first terminal; 250-a first body; 251-a first connection pin; 252-convex column; 126-a second terminal; 260-a second body; 261-a second connection pin; 127-line blocking plate; 128-winding slot; 140-a second skeleton; 141-a second stop plate; 142-a second winding post; 13-a stator winding; 15-a mounting portion; 20-a rotor; 21-a rotating shaft; 200-an electric saw; 201-a power supply; 202-a saw blade; 300-a blower; 301-blower tube.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments, so that the technical solutions and the advantages thereof will be more clearly understood. It is to be understood that the drawings are provided for purposes of illustration and description only and are not intended as a definition of the limits of the invention, but the dimensions shown in the drawings are for convenience and are not to be taken as limiting the scale.

Fig. 1 is a perspective view of a brushless dc motor 100 according to an embodiment of the present invention. The brushless dc motor 100 includes a stator 10 and a rotor 20 rotatable relative to the stator 10. The brushless dc motor 100 is an inner rotor motor, and a housing of the brushless dc motor 100 is omitted in fig. 1 in order to better illustrate the relationship between the stator 10 and the rotor 20. The stator 10 includes a stator core 11, a bobbin 12 fixed to the stator core 11, and a stator winding 13 wound around the bobbin 12. Referring also to fig. 2 to 4, the stator core 11 includes an annular yoke 110 and a plurality of pole teeth 111 extending radially inward from an inner circumference of the yoke 110. The outer circumference of the bottom end of the yoke 110 is provided with a plurality of mounting portions 15 to fix the stator core 11 to a corresponding component (e.g., a housing). The rotation shaft 21 of the rotor 20 is connected with an external element to provide a corresponding driving. The specific structure of the rotor 20 may adopt an existing structure, and will not be described in detail herein.

The bobbin 12 of the stator 10 includes a first bobbin 120 and a second bobbin 140 arranged one above the other. The first bobbin 120 and the second bobbin 140 are mounted and fixed to the stator core 11 so as to face each other from opposite axial ends of the stator core 11. The U-phase, V-phase, and W-phase electromagnetic wires are wound around the first bobbin 120. Referring to fig. 5, the first bobbin 120 includes a first stopper plate 121, a wire passing portion 129 extending vertically upward from the first stopper plate 121, and a first winding post 123 extending vertically downward from the first stopper plate 121. The first stopper plate 121 is annularly arranged. The second bobbin 140 includes a second stopper plate 141 disposed opposite to the first stopper plate 121. The first stopper plate 121 and the second stopper plate 141 abut against both axial ends of the stator core 11, respectively. In addition, the second frame 140 further includes a second winding post 142 extending vertically and upwardly from the second stopper 141, which is symmetrically disposed with respect to the first winding post 123.

Referring to fig. 5 and 6 together, the wire passing portion 129 of the first bobbin 120 includes a base portion 122 extending vertically upward from the first stopper plate 121, a plurality of flange portions 220 extending radially outward from the outer circumference of the base portion 122, and a plurality of conductive terminals 25 fixed to the upper portion of the base portion 122. The first frame 120 is an insulating member except the conductive terminals 25. The second frame 140 is an insulating member. The plurality of conductive terminals 25 are arranged at regular intervals along the circumferential direction of the base portion 122 and protrude from the top of the base portion 122. The plurality of flange portions 220 are arranged at intervals along the circumferential direction of the base portion 122, but the flange portions 220 and the conductive terminals 25 are arranged in a circumferentially staggered manner, that is, one conductive terminal 25 is arranged between every two adjacent flange portions 220. In this embodiment, each of the flange portions 220 forms a first receiving groove 224 and a second receiving groove 225. The first receiving groove 224 and the second receiving groove 225 are opened radially outward to receive the magnet wires. In the present embodiment, the first receiving groove 224 and the second receiving groove 225 both extend along the circumferential direction of the base portion 122 and are arranged in parallel in the axial direction. The base 122 further includes a plurality of fixing portions 124 protruding upward along the axial direction, and the fixing portions 124 are disposed in one-to-one correspondence with the conductive terminals 25. In the present embodiment, the conductive terminals 25 are respectively fixed on the corresponding fixing portions 124 by an over-molding manner. An opening 241 for incoming and outgoing lines is formed between two adjacent fixing portions 124.

Specifically, the plurality of conductive terminals 25 includes a plurality of first terminals 125 and a plurality of second terminals 126. In the present embodiment, the number of the first terminals 125 is three, and the number of the second terminals 126 is six. Three first terminals 125 are adjacently arranged in the circumferential direction of the base portion 122, six second terminals 126 are also adjacently arranged in turn in the circumferential direction, and the first terminals 125 and the second terminals 126 are arranged at equal intervals in the circumferential direction of the base portion 122 as a whole.

Each first terminal 125 includes a first body 250, a first terminal pin 251, and a post 252. In the present embodiment, the first body 250 is fixed to the fixing portion 124, and the first terminal pin 251 is located at a radial outer side of the first body 250. Preferably, the first body 250 is square. The first terminal pin 251 has a hook shape. The post 252 is used for connection with an external power source. In the present embodiment, the protruding pillar 252 axially extends upward to protrude from the top end of the first body 250. The second terminal 126 includes a second body 260 and a second terminal pin 261 located radially outward of the second body 260. In the present embodiment, the first terminal 125 and the second terminal 126 are both of an integrated structure. Preferably, the machining of the terminals is greatly facilitated by forming sheet metal parts or other similar sheet-like structures by bending. In the present embodiment, the second body 260 and the second connection pin 261 have the same shape as the first body 250 and the first connection pin 261, respectively.

Preferably, each flange portion 220 includes a first rib 221, a second rib 222, and a third rib 223 arranged in order from top to bottom in the axial direction. The first receiving groove 224 is formed between the first protruding rib 221 and the second protruding rib 222, the second receiving groove 225 is formed between the second protruding rib 222 and the third protruding rib 223, and a third receiving groove 226 is formed between the third protruding rib 223 and the first stopper plate 121. The first, second and third receiving

slots

224, 225 and 226 are respectively used for receiving U, V, W-phase electromagnetic wires. In an alternative embodiment, for a low voltage motor, the magnet wires are thin and coated with paint, and the flange portion 220 may only form a receiving groove for receiving the magnet wires. Each of the first rib 221, the second rib 222 and the third rib 223 is arranged along the circumferential direction of the base 122 according to the bending condition of the magnet wire passing line. In the present embodiment, the total length of all the first ribs 221 in the circumferential direction of the base 122 is smaller than the total length of all the second ribs 222 in the direction, and the length of all the second ribs 222 in the direction is smaller than the total length of all the third ribs 223 in the direction. In addition, the first rib 221 has a first inclined surface 227 at a position corresponding to the bending position of the corresponding magnet wire, the second rib 222 has a second inclined surface 228 at a position corresponding to the bending position of the corresponding magnet wire, and the third rib 223 has a third inclined surface 229 at a position corresponding to the bending position of the corresponding magnet wire, so that the magnet wire can be more conveniently passed through the wire, and the damage of a sharp edge to the magnet wire is eliminated.

The plurality of first winding posts 123 of the first bobbin 120 are arranged at equal intervals in the circumferential direction. Each first winding leg 123 is configured to cover an upper half of a corresponding pole tooth 111 of the stator core 11, and the corresponding second winding leg 142 of the second bobbin 140 covers a lower half of the corresponding pole tooth. A winding groove 128 is formed radially inward between adjacent two first winding posts 123. The electromagnetic wire is wound on the winding posts (123, 142) corresponding to the first framework 120 and the second framework 140, and is isolated and insulated from the pole teeth 111 through the winding posts (123, 142). The radially inner end of the winding slot 128 is provided with a wire stop 127 to prevent the winding from being taken off the wire. The shape of the winding groove 128 is not particularly limited, and a square groove, a circular groove, or the like may be selected.

Referring to fig. 7a and 7b, the conductive terminals 25 of the present invention are arranged along the counterclockwise direction of the circumference of the first frame 120 by a-i, and the stator winding is wound by the following steps: s1: after connecting a magnetic wire with the terminal a, starting from the terminal a, extending to the terminal d along the corresponding first receiving groove 224 on the outer periphery of the base 122 and connecting with the terminal d, continuing to extend to the terminal g along the corresponding first receiving groove 224 on the outer periphery of the base 122 and connecting with the terminal g, then returning to the terminal a through the corresponding first receiving groove 224 and connecting with the terminal a, and winding the pole tooth 2 of the stator core 11 on the right side of the terminal a to form a winding W2; then, the electromagnetic wire is wound to and connected with the terminal b on the right side of the tooth 2, then extends to the terminal e along the corresponding second receiving groove 225 on the periphery of the base portion 122 and is connected with the terminal pin of the terminal e, continues to extend to the terminal h along the corresponding second receiving groove 225 on the periphery of the base portion 122 and is connected with the terminal h, then returns to the terminal b through the corresponding second receiving groove 225, and winds the tooth 3 on the right side of the terminal b to form a winding W3; then the electromagnetic wire is wound to and connected with the terminal c on the right side of the tooth 3, and then extends to and is connected with the terminal f along the corresponding third receiving groove 226 on the outer periphery of the base 122, and then continues to extend to and is connected with the terminal i along the corresponding third receiving groove 226 on the outer periphery of the base 122, then the magnet wire returns to the terminal c through the corresponding third receiving slot 226, and winds the tooth 4 on the right side of the terminal c to form a winding W4, the magnet wire then connects terminal d to the right and then winds pole tooth 5 to form winding W5, then magnet wire connects terminal e and winds pole tooth 6 to form winding W6 and then connects terminal f, winds pole tooth 7 to form winding W7, then connecting terminal g, winding tooth 8 to form winding W8, connecting terminal h, then winding tooth 9 to form winding W9, then connecting terminal i, then winding tooth 1 to form winding W1, and finally ending back at terminal a.

As can be seen from the above winding, the terminals a to i are divided into three groups of terminals, i.e., U, V, W three-phase terminals, where a, d, and g are one phase, e.g., U phase; b. e, h are a phase, such as a V phase; c. f, i are a phase, for example, W phase. Three terminals belonging to the same phase are all directly connected through electromagnetic wires. Herein, the magnet wire that belongs to between the conductive terminal of the same phase with the direct connection is called isobaric and crosses the line, then in the utility model discloses in, utilize isobaric to cross the line and will belong to the terminal interconnect of same phase, need not to use U, V, W looks terminal ring to saved through the step of cladding forming with embedding U, V, W looks three terminal ring many times among the prior art, effectively reduced the cost.

In the embodiment, the stator windings W1-W9 and all the isobaric passing wires are continuously formed by only one electromagnetic wire through one-time winding, so that the manufacturing process is simple and convenient. It will be appreciated that alternatively the isobaric wires and the windings may be wound separately, i.e. each isobaric wire is wound separately and the windings are wound separately.

Fig. 8 shows a schematic diagram of a stator winding of a brushless dc motor according to another embodiment of the present invention. In this embodiment, the number of terminals is six (A, B, C, D, E, F), the number of windings is also six, and the winding pattern of the stator is similar to that of the above-described embodiment. After a magnet wire is connected with the terminal A, the magnet wire extends to the terminal D along the periphery of the base part and is connected with the terminal D, then the magnet wire returns to the terminal A and is connected with the terminal A, then the pole tooth 1 is wound to form a winding W1, the magnet wire is then connected to terminal B, then extends along the periphery of the base to and is connected to terminal E, continues to extend along the periphery of the base back to where terminal B is connected and then is wound around tooth 2 to form winding W2, and then is connected to terminal C, then extends along the outer periphery of the base to and is connected to terminal F, continues to extend along the outer periphery of the base back to where it is connected to winding teeth 3 to form winding W3, then is connected to terminal D, then winding the teeth 4 to form a winding W4, then connecting the magnet wire with the terminal E, then winding the teeth 5 to form a winding W5, the magnet wire then connects terminal F, then winds the tooth 6 to form winding W6, and finally ends back at terminal a.

Fig. 9 shows a specific example of an electric device having the brushless dc motor 100 according to the present invention, in this embodiment, the electric device is an electric saw 200, which includes the brushless dc motor 100, a power supply 201 for operating the brushless dc motor 100, and a saw blade 202. Fig. 10 shows another specific example of an electric device having the brushless dc motor 100 of the present invention, and in this embodiment, the electric device is a blower 300 including the brushless dc motor 100 and a blower tube 301. The brushless dc motor 100 of the present invention can also be used in other electric devices.

The above description is only a preferred embodiment of the present invention, the protection scope of the present invention is not limited to the above listed embodiments, any person skilled in the art can obviously obtain simple changes or equivalent substitutions of the technical solutions within the technical scope of the present invention.

Claims

1. A stator for a brushless dc motor, comprising: stator core, fixing last bobbin of stator core to and by the electromagnetic wire around locating the last stator winding that forms of bobbin, bobbin includes to support the backstop board of a stator core axial end, certainly the line portion of crossing that the backstop board upwards extends, and certainly the wrapping post of backstop board downwardly extending, its characterized in that, cross the line portion including certainly the basal portion that the backstop board extends, and set up a plurality of conductive terminal on the basal portion, a plurality of conductive terminal are divided into the multiunit, and every group includes two at least conductive terminal, belongs to through electromagnetic wire lug connection between the conductive terminal of same group.

2. The stator of claim 1, wherein the plurality of conductive terminals are evenly spaced along a circumference of the base portion.

3. The stator of claim 1, wherein the bobbin further comprises a plurality of flange portions extending radially outward from an outer periphery of the base portion, the plurality of flange portions being spaced circumferentially of the bobbin and circumferentially offset from the plurality of conductive terminals.

4. The stator of claim 3, wherein each of the plurality of flange portions forms at least one receiving slot for receiving a magnet wire.

5. The stator according to claim 3, wherein each of the plurality of flanges comprises a first protruding rib, a second protruding rib and a third protruding rib sequentially arranged from top to bottom along the axial direction, a first receiving groove is formed between the first protruding rib and the second protruding rib, a second receiving groove is formed between the second protruding rib and the third protruding rib, a third receiving groove is formed between the third protruding rib and the stop plate, the first receiving groove, the second receiving groove and the third receiving groove respectively receive U, V, W three-phase electromagnetic wires, and each receiving groove has an inclined surface where the corresponding electromagnetic wire is bent from the corresponding conductive terminal to enter the receiving groove.

6. The stator of claim 1, wherein the stator winding is a delta winding formed from a magnet wire, and the plurality of sets of conductive terminals are connected by the magnet wire.

7. The stator as claimed in claim 6 wherein said plurality of conductive terminals includes three first terminals and a plurality of second terminals, each said first terminal including a first body secured to said base, a first terminal pin located radially outwardly of said first body, and a post extending axially from said first body, each said second terminal including a second body secured to said base and a first terminal pin located radially outwardly of said second body.

8. The stator according to claim 7, wherein the three first terminals are adjacently arranged in a circumferential direction of the base, the three first terminals and the plurality of second terminals are sequentially and repeatedly arranged in an U, V, W-phase terminal sequence in the circumferential direction of the base, the stator core includes a number of pole teeth having the same number as the plurality of conductive terminals, and windings on the number of pole teeth are in one-to-one correspondence with the plurality of conductive terminals.

9. A brushless dc motor comprising a stator according to any one of claims 1 to 8 and a rotor housed within the stator, the rotor being rotatable relative to the stator.

10. An electric device, characterized by comprising a brushless dc motor according to claim 9.