JPH059170U - Outer rotor motor - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a high-performance outer rotor motor having a reduced defective product rate by preventing the characteristic deterioration of the position detection sensor by providing cooling means for stator heat. A protective section 10 is provided on an externally exposed portion of a printed circuit board 7 provided with a photo interrupter 8 and a connector 9. The protective portion 10 is provided with an opening 11 through which the photo interrupter 8 and the connector 9 communicate with the outside. When the stator 3 is formed, the opening 11 communicates with cold air means outside the die to cool the photo interrupter 8 and the connector 9 portion.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of an outer rotor motor.

[0002]

[Prior Art]

 Various types of outer rotor type motors have been known, but recently, for the purpose of simplifying the structure and reducing the manufacturing process, an outer rotor cup is made of synthetic resin, and a metal frame (hereinafter referred to as a back yoke) is formed inside the outer rotor cup. It is proposed by the applicant that a magnet and a magnet are integrally molded.

FIG. 5 is an example of such a resin-integrated outer rotor type motor. That is, the shaft 1 is rotatably provided via the bearing 2 to the stator 3 having the stator coil 3a and the iron core 3b. Further, a cup-shaped rotor cup 4 is provided around the stator 3 so as to cover the stator 3 at a constant interval. The rotor cup 4 is formed by pouring resin into a mold and integrally molding it with the back yoke 5 and the magnet 6. The center of the shaft 1 is fixed to the protruding portion of the shaft 1 from the stator 3 and is rotatable with the shaft 1.

On the other hand, a printed circuit board 7 is attached integrally with the stator 3 at the end of the stator 3 in the opening direction of the rotor cup 4. A field pole position detecting sensor 8 such as a photo interrupter is attached to a part of the side edge of the printed board 7.

Such a brushless motor includes a stator coil 3 a arranged on the stator 3 and a magnet 6 mounted on the inner peripheral surface of the rotor cup 4 at a position corresponding to the stator coil 3 a via a back yoke 5. The rotor cup 4 is rotating. Further, the printed circuit board 7 switches the current to the stator coil 3a, and the rotation of the rotor cup 4 is controlled by the detection sensor 8 such as a photo interrupter.

By the way, in such an outer rotor motor, a member for protecting the printed circuit board 7 from an external impact, dust and the like, and a member for attaching the motor to the fixing member are required. For this reason, a protective portion for protecting the printed circuit board 7 and fixing the motor to the fixing member is provided by resin. The protective portion is provided so as to cover the exposed portion of the printed board 7, and is integrally molded with the stator 3 together with the printed board 7 by a mold. That is, the resin is poured into the lower die having the stator coil 3a and the iron core 3b attached thereto and the upper die having the printed circuit board 7 having the detection sensor 8 attached thereto, and the upper die and the lower die are connected to each other to print. The stator 3 is integrally molded together with the substrate 7 and the protection portion.

The exposed portion of the printed circuit board is protected by such a protective portion. Further, by forming a mounting hole in the side edge portion of the protective portion, the motor can be mounted on the fixing member with a screw or the like.

[0008]

[Problems to be solved by the device]

 However, in order to integrally mold the stator 2 with resin, it is necessary to apply heat during molding. This temperature is about 120 to 160 ° C. for the thermosetting resin and about 200 ° C. or higher for the thermoplastic resin. That is, in order to provide the protective portion on the exposed portion of the printed circuit board, heat exceeding 100 ° C. is applied to the printed circuit board 7 and the detection sensor 8 inside the mold. The detection sensor 8 such as a photo interrupter is likely to deteriorate its characteristics under a high temperature exceeding 100 ° C. If the position detection sensor deteriorates in characteristics, it may affect the operation and life of the position detection sensor, and may also cause defective products such as malfunction of the outer rotor motor.

The present invention is provided to solve the above-mentioned problems of the prior art, and an object thereof is to provide a cooling means for stator molding heat for a position detection sensor, It is an object of the present invention to provide a high-performance outer rotor motor that prevents deterioration and reduces the defective product generation rate.

[0010]

[Means for Solving the Problems]

 The outer rotor motor of the present invention comprises a stator, a cup-shaped rotor cup provided so as to cover the stator, and a printed circuit board provided at an end portion of the stator and having a field pole position detecting sensor at a side edge portion. In the outer rotor motor, in which the stator and the printed circuit board are integrally formed, a protective portion for protecting the printed circuit board is formed in the vicinity of the field magnetic pole position detection sensor with an opening communicating with the cool air means outside the mold. Is provided.

[0011]

[Action]

 In the outer rotor motor of the present invention having the above-mentioned structure, when the stator is integrally molded with the printed circuit board by the mold, cold air is blown from the opening of the printed circuit board protection portion by the cool air means outside the mold. Therefore, the field magnetic pole position detection sensor inside the opening is cooled even when the molding heat of the stator is applied, so that the temperature does not rise above 100 ° C. Therefore, the field pole position detecting sensor does not deteriorate in characteristics due to heat. That is, it is possible to provide a high-performance outer rotor motor with a reduced defective product rate.

[0012]

【Example】

 An embodiment of the outer rotor motor of the present invention will be described below with reference to FIGS. In this embodiment, the same members as those in the conventional technique are designated by the same reference numerals, and the description thereof will be omitted.

That is, as shown in FIGS. 1 and 2, in the outer rotor motor of this embodiment, a field magnetic pole position detection sensor 8 such as a photo interrupter and a connector are provided at a part of a side edge of the printed board 7. 9 is provided. Further, when the surface of the printed circuit board 7 on which the detection sensor 8 and the like are provided is the front surface, the back surface and the side surface, and a portion exposed to the outside on the front surface is provided with a protection portion 10 for protection.

By the way, as shown in FIG. 3, a bushing 12 is provided on the surface of the printed board 7 from the side edge portion of the printed board 7 near the detection sensor 8 and the connector 9 so as to surround them. ing. The bushing 12 forms an opening 11 in the protective portion 10 that opens toward the edge of the print substrate 7. Through this opening 11, the detection sensor 8 and the connector 9 are exposed in the upper part and in the direction of the side edge of the printed circuit board 7 and are in communication with the outside.

On the other hand, as shown in FIG. 2, the protective portion 10 around the side edge of the printed circuit board 7 is provided with a peripheral portion sufficiently larger than the printed circuit board. A mounting hole 13 for fixing the outer rotor motor to the fixing member with a screw or the like is formed in this peripheral portion.

The stator 3 as described above is formed by upper and lower molds 14 and 15 as shown in FIG. That is, resin is poured into the lower mold 14 forming the main body of the stator 3 and the upper mold 15 on which the printed circuit board 7 is mounted, and the lower mold 14 and the upper mold 15 are connected to each other, so that the printed circuit board 7 and the protection unit 10 are connected. It is integrally molded with. At this time, since the printed circuit board 7 is provided with the bushing 12, the resin does not flow into the periphery of the detection sensor 8 and the connector 9, and the opening 11 is formed in the protective portion 10. On the other hand, the side surfaces corresponding to the openings 11 of the molds 14 and 15 are formed so as to be freely ventilated. That is, even when the upper and lower molds 14 and 15 are connected to each other, the opening 11 of the protective portion 10 is in a state of communicating with the outside. Therefore, when the stator 3 is integrally molded by the molds 14 and 15, the detection sensor 8 and the connector 9 provided in the opening 11 communicate with the outside. On the other hand, a blower (not shown) is provided near the opening 11 corresponding portion of the molds 14 and 15 described above. Cooling air is blown from the blower means to the opening 11. By the way, such a mold is also provided with a portion corresponding to the mounting hole 13 formed in the protective portion 10.

The outer rotor motor of the present embodiment as described above has the following effects.

That is, when the stator 3 is integrally molded with the molds 14 and 15, the opening 11 communicates with the outside. Therefore, when air is blown into the opening 11 by an external cooling air means, the inside of the opening 11 is closed. The detection sensor 8 and the connector 9 are cooled. Therefore, even if heat is applied during molding of the stator 3, the temperature of the detection sensor 8 such as the photo interrupter and the connector 9 does not exceed 100 ° C. Therefore, the characteristics of the detection sensor 8 and the connector 9 do not deteriorate, and the exposed portion of the printed circuit board 7 can be sufficiently protected. Furthermore, the motor can be attached to the fixing member without damaging the printed circuit board 7. It is possible to provide the outer rotor motor provided with the protection unit 10 capable of performing the above.

It should be noted that the present invention is not limited to the above-described embodiment, and the specific shape of each member, the mounting position and method of each member, etc. can be appropriately changed.

For example, depending on the positions where the field pole position detection sensor 8 and the connector 9 are attached, the openings 11 provided in the protection unit 10 may be provided with different openings, and may be cooled respectively. it can.

Further, depending on the place where the outer rotor motor is installed, it is possible to separately provide a mounting member without forming the mounting hole 11 in the protective portion 10.

On the other hand, the blowing means is not limited to one provided as a separate member outside the die, and there is no problem even if it is provided on the outer wall of the die. In addition, it is not limited to blowing air from outside the mold, but it is also possible to provide a blowing pipe in the blowing means, insert this blowing port inside the opening and blow cooling air directly to the detection sensor etc. to cool it. Is. This allows efficient cooling.

[0023]

[Effect of the device]

 According to the present invention, since the position detecting sensor is provided with the cooling means against the heat of the stator forming, the characteristic deterioration of the position detecting sensor can be prevented. Therefore, it is possible to provide a high-performance outer rotor motor with a reduced defective product rate.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of an outer rotor motor of the present invention.

FIG. 2 is a plan view showing a stator of the outer rotor motor shown in FIG.

FIG. 3 is an enlarged perspective view of a main part of the outer rotor motor of FIG.

FIG. 4 is a side view showing a mold for forming the outer rotor motor of FIG.

FIG. 5 is a side cross-sectional view of the outer rotor motor in a state in which a protection portion is not provided.

[Explanation of symbols]

 1 shaft 2 bearing 3 stator 4 rotor cup 5 back yoke 6 magnet 7 printed circuit board 8 detection sensor 9 connector 10 protective part 11 opening 12 bushing 13 mounting hole 14 lower mold 15 upper mold

Claims (1)

[Claims for utility model registration] Claims: 1. A stator, a rotor cup that is formed into a cup shape with an end surface and a circumferential surface, and is provided so as to cover the stator; and a side edge provided at the end portion of the stator. In the outer rotor motor, in which the stator and the printed circuit board having the position detection sensor are provided, and the stator and the printed circuit board are integrally molded by a mold, a protective part for protecting the printed circuit board and a protective part formed near the position detection sensor are formed. An outer rotor motor, comprising: an opening communicating with a cool air means outside the die.