JP2007116867A - Brushless motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an easy-to-assemble brushless motor exhibiting good heat dissipation properties in which winding work of a coil is enhanced and space factor of the coil can be enhanced even in case of small size. <P>SOLUTION: Split armature cores 3 are inserted into an insulating material 4 of resin to cover a slot formed in the insulating material from above and below in the axial direction such that the outer circumferential part 3a touches the inner circumferential surface of a tubular case 2 made of a magnetic material forming a magnetic path and secured in place. An exciting coil 5 is wound around each insulated split armature core, and a rotor magnet 7 to which a rotating shaft 6 is fixed is arranged on the inside of each split armature core. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a brushless motor structure suitable for a high-speed and high-power motor used for office automation equipment and in a high-speed responsive industrial field at a rotational speed of 2000 to 7000 r / min and an output of 5 W to 30 W.

  Conventionally, various types of inner rotor type brushless motors have been proposed (for example, Patent Document 1). This type of brushless motor is shown in FIG. A conventional brushless motor includes a cylindrical case 101 made of a nonmagnetic material, an integrated armature core 102 made of an electromagnetic steel plate incorporated in the cylindrical case 101, and a coil (copper wire) wound around the armature core 102. 103, a rotor magnet (permanent magnet rotor) 104 disposed on the inner peripheral side of the armature core 102 with a predetermined gap, and a rotary shaft fixed integrally with the rotor magnet 104 and transmitting a motor output to a driving load 105 is a main component.

The integrated amateur core 102 has an annular outer peripheral portion 102a for securing a magnetic path, and has a plurality of T-shapes from the inner peripheral surface of the outer peripheral portion 102a toward the center. The teeth 102b are projected and covered with an insulating material (coating), and the coil 103 is wound around the slot 102c formed by the covering of the insulating material to form an exciting coil. The armature core 102 is assembled to the cylindrical case 101 so that the outer peripheral portion 102 a is in contact with the inner peripheral surface of the cylindrical case 101.
JP-A-8-309945

  By the way, the conventional integrated armature core 102 has an outer peripheral portion 102a in order to secure a magnetic path, so that the winding area of the coil 103 wound around the slot 102c is reduced in the radial direction. The space factor was reduced.

  Further, since the armature core 102 has an annular shape, the coil 103 needs to be wound around the slot 102c from the inner peripheral side. In order to form the exciting coil by winding the coil 103 from the inner peripheral side in this way, it is necessary to secure a winding space for passing the nozzle of the winding machine between the slots 102c, and the exciting coil is formed. The ratio of the area (coil space factor) to the portion to be reduced decreases as the armature core 102 becomes smaller and the number of slots increases, and the coil winding workability also deteriorates.

(Object of invention)
An object of the present invention is to provide a brushless motor that can improve the coil winding workability, increase the coil space factor even if it is small, and is easy to assemble and has good heat dissipation. It is what.

  In order to achieve the above object, according to the present invention, each of the divided armature cores is in contact with the inner circumferential surface of a cylindrical case made of a magnetic material forming a magnetic path. In addition, it is inserted and fixed to an insulating material made of resin so as to cover the slot formed in the insulating material from above and below in the axial direction so that the exciting coil is insulated. A rotor magnet wound around each of the divided armature cores and having a rotation shaft fixed thereto is provided as a brushless motor that is disposed inside each of the divided armature cores.

  According to the above configuration, each of the split armature cores is disposed so that the outer peripheral portion thereof is in contact with the inner peripheral surface of the cylindrical case made of a magnetic material and is positioned at predetermined intervals, thereby forming a magnetic path in the armature core. Therefore, the coil winding work can be performed from the outer peripheral side of the amateur core, and the coil space factor can be increased even if it is small in size.

  In addition, a split armature core is inserted into a slot formed of an insulating material, and the split armature core is covered with an insulating material from above and below in the axial direction, so that it is easy to assemble and inserted into the insulating material. Since the portion of the divided armature core that is not formed is exposed without being covered with insulation, the heat dissipating property is good.

  ADVANTAGE OF THE INVENTION According to this invention, while making coil winding workability | operativity favorable, even if it is small, a coil space factor can be raised, and it is easy to assemble and can provide a brushless motor with favorable heat dissipation. Is.

  As shown in the following examples.

  1 to 4 show a brushless motor according to an embodiment of the present invention. Specifically, FIG. 1 is a cross-sectional view in the longitudinal direction (axial direction) of the brushless motor, and FIG. 2 is a lateral direction (axial direction) of the brushless motor. 3 is a perspective view showing a split armature core, and FIG. 4 is a cross-sectional view showing an insulating core.

  In these drawings, a brushless motor 1 includes a cylindrical case 2 made of a magnetic material to form a magnetic path, an amateur core made up of a plurality of (in the embodiment, six) divided arm cores 3, and a divided armature core. 3 has an insulating core 4 made of resin for insulating and fixing 3, an excitation coil 5, and a rotor magnet 7 made of a plastic magnet or the like to which a rotating shaft 6 is fixed.

  As shown in FIGS. 1 and 2, the plurality of split armature cores 3 having the shape shown in FIG. 3 are in contact with the inner peripheral surface of the cylindrical case 2 and at a predetermined interval (in the embodiment, 60 a). It is inserted and fixed to the insulating core 4 so as to cover the slot formed in the insulating core 4 from above and below in the axial direction. Then, the exciting coil 5 is wound around the portion of the teeth 3 b of each divided arm core 3 that is insulated by the insulating core 4. The rotor magnet 7 to which the rotating shaft 6 is fixed is arranged inside the plurality of divided armature cores 3 with a predetermined gap.

  As described above, the armature core is divided into a plurality of divided armature cores 3 and the cylindrical case 2 is used as a member for forming a magnetic path, so that the conventional armature core 102 of FIG. 5 is used. An annular outer peripheral portion 102a for forming a magnetic path can be an outer peripheral portion 3a that is shortened in the circumferential direction. Therefore, the winding work of the coil 5 from the outside of the divided armature core 3 can be performed, and the work becomes favorable. Further, by making the outer peripheral portion 3a shortened in the circumferential direction, as is apparent from the comparison between FIG. 2 and FIG. , Its output can be improved.

  Further, the split armature core 3 is inserted into the slot formed by the insulating core 4, and the split armature core 3 is covered with an insulating material from above and below in the axial direction as shown in FIG. Is easy. Further, in the case of the conventional example of FIG. 5, the entire armature core is covered with insulation, whereas in the case of this embodiment, as shown in FIG. 1, the divided armature core 3 not inserted into the insulation core 4 is used. Since this part is in an exposed state (exposed state), heat dissipation is good.

  A housing 8 is attached to the cylindrical case 2, and a bearing 9 is fixed to the housing 8. A bearing 11 is fixed to the end bracket 10. The bearing 9 and the bearing 11 hold the rotating shaft 6 fixed to the rotor magnet 7 so as to be rotatable.

  A plurality of pins 12 are press-fitted into one end side of the insulating core 4, and the pins 12 are used as members for starting and ending winding of the coil 5. That is, the coil 12 is wound from the outside into the slot of the insulating core 4 (that is, the portion of the teeth 3b of the split armature core 3) with the pin 12 being started to wind the coil 5, and the end of the winding is also connected to the pin 12. It will be. By providing the pins 12 in this way, coil winding is further facilitated.

  The pins 12 are connected to the circuit wiring board 13. On the circuit wiring board 13, various electronic components for the motor drive circuit, such as three Hall elements 14 that detect the position in opposition to the rotor magnet 7, are arranged.

  Finally, the effects in the above-described embodiment will be enumerated again below.

  Since the amateur core is divided into a plurality of divided armature cores 3 and the cylindrical case 2 is used as a member for forming a magnetic path, the circumferential length of the outer peripheral portion 3a of the divided armature core 3 is shortened. It is possible to wind the coil 5 from the outside of the split armature core 3, and the work can be improved, and the coil space factor can be increased even if it is small. .

  Further, since the split armature core 3 is inserted into the slot formed by the insulating core 4 and the split armature core 3 is covered with an insulating material from the upper and lower sides in the axial direction, the assembly is facilitated and the heat Dispersibility is good.

  Moreover, since the pin 12 is press-fitted into the end portion of the insulated divided armature core 3, the workability of the coil winding work is further improved.

  As another effect, in the above embodiment, since the insulating core 4 made of resin forms a slot, the shape of the split armature core 3 can be easily changed.

It is a longitudinal section showing a brushless motor concerning one example of the present invention. It is a cross-sectional view showing a brushless motor according to an embodiment of the present invention. It is a perspective view which shows the split-type amateur core concerning one Example of this invention. It is a longitudinal section showing an insulating core concerning one example of the present invention. It is a cross-sectional view showing a conventional brushless motor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Brushless motor 2 Cylindrical case 3 Split-type amateur core 3a Outer peripheral part 4 Insulating core (insulating material)
5 Coil 6 Rotating shaft 7 Rotor magnet 12 Pin

Claims (1)

Each of the armature cores divided into a plurality of parts is made of resin so that the outer peripheral part is in contact with the inner peripheral surface of the cylindrical case made of a magnetic material forming a magnetic path and is located at predetermined intervals. Is inserted and fixed so as to cover the slot formed in the insulating material from above and below in the axial direction.
A brushless motor, wherein a magnet for excitation is wound around each of the divided armature cores insulated, and a rotor magnet having a fixed rotation shaft is disposed inside each of the divided armature cores.

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