GB2362269A

GB2362269A - Double wire winding in a brushless dc motor

Info

Publication number: GB2362269A
Application number: GB0016316A
Authority: GB
Inventors: Alex Horng
Original assignee: Sunonwealth Electric Machine Industry Co Ltd
Current assignee: Sunonwealth Electric Machine Industry Co Ltd
Priority date: 2000-05-10
Filing date: 2000-07-03
Publication date: 2001-11-14
Also published as: JP2001327131A; GB0016316D0; DE10033466A1

Abstract

A DC brushless motor having radial winding and radial air gap includes a stator 202 includes a number of pole arms 201 and two simultaneously wound conducting wires 210, 220. The conducting wires are continuously wound around the pole arms in sequence -figs 2,3 to form the radial winding. At least one end of each conducting wire 212/211 or 222/221 forms a connection for connecting with a control circuit whilst the other end may interconnect to the other respective wire to form series or parallel connected coils. A winding method is also disclosed.

Description

2362269 1 DC BRUSHLESS MOTOR HAVING RADIAL WINDING AND RADIAL AIR GAP 2

AND METHOD FOR CARRYING OUT THE RADIAL WINDING 3 Back(ground of the Invention

4 1. Field of the Invention

The present invention relates to a DC brushless motor having radial winding and radial 6 air gap, and more particularly to a DC brushless motor having a stator that is constituted by 7 simultaneously winding two conductive wires around pole arms of a radial bobbin to form the 8 radial winding. The present invention also relates to a method for carrying out the radial 9 winding.

2. Description of the Related Art

11 U.S. Patent No. 5,289,089 to Aoki issued on Feb. 22, 1994 discloses a motor drive 12 circuit and motor drive system using the circuit thereof U.S. Patent No. 5,959,377 to Horng 1 issued on Sep. 28, 1999 discloses a miniature brushless motor having radial air gap and single J 14 coil with axial winding. The drive circuits disclosed in the two U.S. patents are suitable for ordinary brushless DC motors having a single set or two sets of winding.

C' I I 16 Fig. 5 of the drawings illustrates a stator 100 formed by means of a conventional radial 17 winding method. Fig. 6 illustrates a method for carrying out the radial winding of conducting 18 wires 111 around the pole anns 112 of the stator 100. An end of the conducting wire I I I forms 19 a first connection V i before winding., the conducting wires I 11 around the stator 100. When the conducting wire I I I has been wound around a half number of the pole arms 112 of the stator 21 100, the winding procedure is halted for pulling out the conducting wire 111 to form a second ?? connection Vo (the common connection), then the winding procedure continues for the 23 remaining the pole arms 112. After the winding procedure is finished, the other end of the 24 conductin,,., wire I I I forms a third connection V2. Thus, three connections are provided after winding the conducting wire I I I around the stator 100 is finished. The stator 100 may use the 26 conventional fan motor driver shown in Fig. 2 of U.S. Patent 5,289,090 to generate alternating 27 rotational magnetic fields to thereby drive the rotor 300 with magnetic poles N and S.

I 1 Nevertheless, the winding procedure must be interrupted for formation of the second 2 connection (the common connection Vo).

Figs. 7 and 8 illustrate a stator 100 using another conventional radial windi 1 ing method.

4 This method also winds a conducting wire III around pole arms 112. An end of the conducting wire III forms a first connection Vi before winding the conductina, wires III I 1 1-3 6 around the stator 100. After the winding procedure is finished, the other end of the conducting 7 wire I I I forms a second connection V_z. The stator 100 may use the conventional fan motor 8 driver shown in Fig. 2 of U.S. Patent 5,959,3377 to generate alternatina rotational magnetic 9 fields to thereby drive the rotor 3300 with magnetic poles N and S. Nevertheless, the winding

ID procedure is relatively long, as a single conducting wire I I I must be wound around each pole 11 arm 112 of the stator 100 for a predetermined amount of turns. The time for finishing the 12 winding cannot be decreased unless the winding speed is increased. Yet, the winding speed 11) has a limit.

14 It is, therefore, a long and unfulfilled need in the art to solve the interruption during 1> I'D winding procedure and to reduce the overall winding time.

16 Summary of the Invention

17 In view of the above-mentioned drawbacks, the present invention provides a method for is forming the winding of the stator by means of simultaneously winding two conducting wires.

19 The winding efficiency is improved, as each conducting wire needs to be wound for just a half of turns to finish winding of the stator winding with required turns. After formation of the 21 stator winding by means of the method of simultaneous winding of two conducting wires, an T? end of one conducting wire and an end of the other conducting wire are connected to form a 2 33 common connection after formation of the stator winding, thereby forming a stator windina 24 with three connections for brushless DC motors. This avoids interruption in the winding procedure for dual winding for brushless DC motors.

26 Alternatively, after formation of the stator winding, a second end of one conducting wire 27 and a first end of the other conducting wire are connected in series, and a first end of one 2 I conducting wire and a second end of the other conducting wire are fonning two connections I C) 1=) 2 for a brushless motor with sinale winding.

0 3 The number of the connections in response to a brushless motor with single winding or In "D 4 dual winding can be determined after formation of the stator winding. The time for forming the stator winding is reduced, and the stator winding so fornied can be driven by various drive 6 circuits to suit different types of motors.

7 It is the primary object of the present invention to provide a DC brushless motor having 8 radial winding and radial air gap and a method for carrying out the radial winding by means of Z 0 9 simultaneously winding two conducting wires around each pole arm of the stator. The winding Z7 1=) procedure needs not to be interrupted for forming connection, and the winding time is reduced I I by half, thereby improving, the winding efficiency for the stator.

12 It is another object of the present invention to provide a DC brushless motor having radial winding and radial air gap and a method for carrying out the radial winding, wherein it 14 can be decided to have two or three connections after formation of the stator winding such that the stator can be applied to brushless motors having a single winding or dual winding Z) Z) In 1 16 It is a further object of the present invention to provide a DC brushless motor having 17 radial winding and radial air gap and a method for carrying out the radial winding by means of 17 17 C 18 winding two conducting wires simultaneously. The force for pulling the conducting wires is I ID I-) C.

19 imparted to the conducting wires equally. Thus, the conducting wires are less likely to break during the winding process, thereby improving the winding efficiency.

21 A DC brushless motor having radial winding and radial air gap in accordance with the present invention includes a radial stator bobbin and two conducting wires with different 23) colors. The radial stator bobbin includes a plurality of pole arms around which the conducting 24 wires are wound. The two conducting wires are continuously wound around each of the pole arms in sequence to form the radial winding for constituting the stator. Ends of the conducting 26 wires form connections for connecting with a control drive circuit.

3 Other objects, specific advantages, and novel features of the invention will become more apparent from the following detailed description and preferable embodiments when taken in conjunction with the accompan ing drawings.

Y1 11 117 4 Brief Description of the Drawing

Fig. I is a schematic structure of a first embodiment of a motor in accordance with the 6 present invention.

7 Fig. 2 is a schematic view illustratincr a stator windin- method for the first embodiment.

8 Fig. 3 is a schematic structure of a second embodiment of the motor in accordance with 9 the present invention.

Fig. 4 is a schematic view illustratina a stator winding method for the second 17, I= "D I I embodiment.

12 Fig. 5 is a schematic view illustrating a conventional radial dual winding for a brushless C 1 0 13 DC motor with four pole arms.

14 Fig. 6 is a schematic view illustrating a method for forming a radial dual winding in Fig 1-7 17 5.

16 Ficy. 7 is a schematic view illustrating a conventional radial sin-le windinc, for a 1:1 Z Z' 17 brushless DC motor with four pole arms.

is Fig. 8 is a schematic view illustrating a method for forming the radial single winding in z 11 19 F i g. 7.

Detailed Description of the Preferred Embodiments

21 Preferred embodiments in accordance with the present invention will now be described with reference to the accompanying drawings.

1 1 23) Fig. 1 illustrates an embodiment of a motor in accordance with the present invention.

24 The motor includes a radial stator bobbin 200 with four pole arms 201 and a rotor -')00 with magnetic poles N and S. First and second conducting wires 210 and 220 are wound around the 26 pole arms 201 to for-in a winding 202, thereby constituting the stator. The winding 202 may 27 cooperate with a control drive circuit (e.g., drive circuits disclosed in U.S. Patents 5,289,089 4 I and 5,959,3)77) to generate alternating magnetic fields in radial direction of each pole arm 20 1,

2 thereby driving the rotor 300 with magnetic poles N and S. Each conducting wire 210, 220 needs to be wound for just a half of turns to finish winding of the stator winding 202 with 4 required turns.

After formation of the winding, 202 on the stator bobbin 200, it can then be decided the 6 number (two or three) of the connections to be connected with the drive circuit. If three 7 connections are required, a first end 211 of the first conducting wire 210 is used as a first 8 connection Vi, a second end 212 of the first conducting wire 210 and a first end 221 of the 9 second conducting, wire 220 are connected to form a second connection Vo, and a second end 222 of the second conducting wire 220 is used as a third connection V2. Thus, interruption of 11 winding procedure in the conventional method for forming the connection Vo is avoided. The 12 stator so constructed can be operated with a control circuit so as to be used with a brushless 13 DC motor with dual winding.

14 If only two connections are required, the second end 212 of the first conducting wire 210 and the first end 221 of the second conducting wire 220 are connected in series, and the 16 first end 211 of the first conducting wire 210 and the second end 222 of the second conducting 17 wire 220 are forming two connections. A stator with two is thus formed. The winding process I'D 18 is simplified, as the number of connections can be determined after formation of the stator 19 winding.

Fig. 2 is a schematic view illustratino, a stator windino, method for the first embodiment.

21 As illustrated in Figs. I and 2, the first conducting wire 210 and the second conducting wire 1.7 Z) 1 22 220 are simultaneously wound around pole arm 201 a along a clockwise direction. Then, the 233 first conductingwire 210 and the second conducting wire 220 are simultaneously wound -7 1 0 24 around pole arm 201 b along a counterclockwise direction. Next, the first conducting wire 210 and the second conducting wire 220 are simultaneously wound around pole arm 201c along 26 the clockwise direction. Finally, the first conducting wire 22 10 and the second conducting wire 27 990 are simultaneously wound around pole arm 201d along the counterclockwise direction.

I Namely, the first and second conducting wires 210 and 220 are continuously wound around 2 the pole arms in sequence to form the winding, wherein the winding directions for two 3 adjacent pole arms are opposite to each other. No interruption during the winding procedure 4 for making the connection is required. The number of the connections can be decided after formation of the stator winding for a single-winding motor or dualwinding motor. The 0 6 winding process is not interrupted, and the winding time is reduced by half Further, the 7 conducting wires are wound simultaneously such that the conducting wires are less likely to 8 break during the winding process.

9 Fig. 3 is a schematic structure of a second embodiment of the motor in accordance with the present invention. Fig. 4 is a schematic view illustrating a stator winding method for the C In 11 second embodiment. The first conducting wire 210 and the second conducting wire 220 are 12 simultaneously wound around pole arm 201 a and pole arm 201c along a clockwise direction.

Then, the first conducting wire 210 and the second conducting wire 220 are simultaneously 14 wound around pole arm 201b and pole arm 201d along a counterclockwise direction. Namely, the first and second conducting wires 210 and 220 are wound around two non-adjacent pole 16 arms alona a direction and then wound around the other two non- adjacent pole arms along a z 1=7 17 reverse direction to form the winding. No interruption during the winding procedure for 18 making the connection is required. The first conducting wire and the second conducting wire 19 are of different colors in appearance.

Although the invention has been explained in relation to its preferred embodiment as 21 mentioned above, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention. It is, therefore, 23) contemplated that the appended claims will cover such modifications and variations that fall 24 within the true scope of the invention.

6

Claims

I What is claimed is:

2 1. A DC brushless motor having radial winding and radial air gap, comprising:

a radial stator bobbin including a plurality of even-numbered pole arms; 4 a first conducting wire having a first end and a second end; a second conducting wire having a first end and a second end, the first conducting wire 6 and the second conducting wire being simultaneously and continuously wound around the pole 7 arms of the stator bobbin in sequence to forin a winding and to form at least two connections 8 by the first end and the second end of the first conducting wire and the first end and the second 9 end of the second conducting wire, said at least two connections being adapted to be connected to a control drive circuit; 11 whereby the winding on the stator bobbin cooperates with the drive circuit to aenerate 12 alternating magnetic fields in a radial direction of the stator bobbin to drive a rotor with magnetic poles N and S.

14 2. The DC brushless motor having radial winding and radial air gap as claimed in claim 1, wherein the first conducting wire and the second conducting wire are simultaneously wound 16 around each said pole arm, and wherein the first end of the first conducting wire is used as a 17 first connection, the second end of the first conducting wire and the first end of the second 18 connecting wire are connected to form a second connection, and the second end of the second 19 conducting wire is used as a third connection, thereby forming a stator winding with three connections.

21 1 The DC brushless motor having radial winding and radial air gap as claimed in claim 1, T) wherein the first conducting wire and the second conducting wire are simultaneously wound 1 2 33 around each said pole arm, and wherein the second end of the first conducting wire and the 24 first end of the second conducting wire are connected in series, and the first end of the first conductina wire and the second end of the second conductinc, wire are forming two 26 connections, whereby forming a stator winding with two connections.

7 1 4. The DC brushiess motor having radial winding and radial air gap as claimed in claim 1, wherein the first conducting wire and the second conducting wire are of different colors in 3 appearance.

4 5. A method for forn-iing a winding for a DC brushless motor having radial winding and radial air gap, comprising:

6 winding two conducting wires simultaneously around one of a plurality of even 7 numbered pole arms of a radial stator bobbin one by one until the first conducting wire and the 8 second conducting wire are wound around all of the pole arms in a continuous manner and in 9 sequence, thereby forming a winding on the radial stator bobbin, wherein the winding directions for two adjacent pole arms are opposite to each other; I I whereby no interruption in the winding process is required for forming a connection.

12 6. The method as claimed in claim 5, wherein after formation of the winding on the stator 13 bobbin, the first end of the first conducting wire is used as a first connection, the second end of 14 the first conducting wire and the first end of the second connecting wire are connected to form a second connection, and the second end of the second conducting wire is used as a third 16 connection, thereby forming a stator winding with three connections.

17 7. The method as claimed in claim 5, wherein after formation of the winding on the stator 18 bobbin, the second end of the first conducting wire and the first end of the second conducting 19 wire are connected in series, and the first end of the first conducting wire and the second end of the second conductinc, wire are fori-ninc, two connections, whereby forminc, a stator windinc, 21 with two connections.

8. The DC brushless motor having radial winding and radial air gap as claimed in claim 5, 2.33 wherein the first conducting wire and the second conducting wire are of different colors in 24 appearance.

9. A method for forming a winding for a DC brushless motor having radial windino, and radial 26 air gap, comprising:

8 I winding two conducting wires simultaneously around two of a plurality of even ? numbered pole arms of a radial stator bobbin alona, a direction, said two pole arms being not C; 3 adjacent to each other; 4 winding the two conducting wires simultaneously around next two non-ad acent said pole arms along a reverse direction; and 6 winding the two conducting wires simultaneously around further next two non-adjacent t; 1 1 7 said pole arms along the direction until the first conducting wire and the second conducting I - ID 8 wire are wound around all of the pole arms, thereby forming a winding on the radial stator 9 bobbin; whereby no interruption in the winding process is required for forming a connection.

I 1 10. The method as claimed in claim 9, wherein after formation of the winding on the stator 12 bobbin, the first end of the first conducting wire is used as a first connection, the second end of 0 J the first conducting wire and the first end of the second connecting wire are connected to form V 14 a second connection, and the second end of the second conducting wire is used as a third connection, thereby forming a stator winding with three connections.

16 11. The method as claimed in claim 9, wherein after formation of the winding on the stator 0 17 bobbin, the second end of the first conducting wire and the first end of the second conducting is wire are connected in series, and the first end of the first conducting wire and the second end 19 of the second conducting wire are forming two connections, whereby forming a stator winding with two connections.

21 12. The DC brushless motor having radial winding and radial air gap as claimed in claim 9, wherein the first conducting wire and the second conducting wire are of different colors in 2 33 appearance.

9