JPH08317612A - Manufacture of outer rotor motor - Google Patents

Abstract

PURPOSE: To manufacture the high-performance outer rotor motor, whose occurring rate of defective products is decreased, by preventing the deterioration of the characteristics of electronic parts due to heat when a printed board having the electronic parts and a stator are molded as a unitary body by resin. CONSTITUTION: When a stator 3 and a printed board 7 are molded as a unitary body, a metal mold having a space part having the opening part for communication to the outside of the metal mold, wherein a detection sensor 8 on the printed board 7 and a connector 9 are contained, and a bushing 12 for preventing the inflow of the unitary molding resin into the space part is used. Then, the detection sensor 8 and the connector 9 are arranged in the space part of the metal mold, and the stator 3 and the printed board 7 are mounted Cooling air is blown into the space part from the opening part 11, and the detection sensor 8 and the connector 9 are cooled. During this period, the stator 3 and the printed board 7 are molded as a unitary body by the resin filled in the metal mold.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an improvement in a method for manufacturing an outer rotor motor.

[0002]

2. Description of the Related Art Outer rotor type motors have been known for a long time, but recently, for the purpose of simplifying the structure and reducing the number of manufacturing processes, the outer rotor cup is made of synthetic resin and has a metal frame inside. The one in which a magnet (hereinafter referred to as a back yoke) and a magnet are integrally molded has been proposed by the present applicant.

FIG. 5 shows an example of such a resin-integrated outer rotor type motor, which includes a stator coil 3a.
And a stator 3 in which an iron core 3b is disposed, a shaft 1 rotatably supported by the stator 3 via a bearing 2, and a stator 3 fixed to the shaft 1
A cup-shaped rotor cup 4 provided at a constant interval around the stator 3 so as to cover the stator 3 and a printed circuit board integrally attached to the stator 3 at the end of the stator 3 in the opening direction of the rotor cup 4. It consists of 7.

The rotor cup 4 is integrally molded of resin with the back yoke 5 and the magnet 6, and the central portion thereof is fixed to the protruding portion of the shaft 1 from the stator 3. The magnet 6 is mounted on the inner peripheral surface of the rotor cup 4 at a position corresponding to the stator coil 3 a via the back yoke 5. Further, a field magnetic pole position detection sensor (hereinafter referred to as a detection sensor) 8 such as a photo interrupter is attached to a part of a side edge of the printed board 7.

Such a brushless motor includes a stator coil 3a arranged on the stator 3 and a rotor cup 4
The rotor 6 is rotated by the magnet 6 mounted on the inner peripheral surface of the rotor. Further, the printed circuit board 7 switches the current to the stator coil 3a, and the detection sensor 8 controls the rotation of the rotor cup 4.

By the way, the outer rotor motor as described above requires a member for protecting the printed circuit board 7 from an external impact and dust, and a member for attaching the motor to the fixed member. Therefore, the resin is provided with a protective portion that covers and protects the exposed portion of the printed circuit board 7 and fixes the motor to the fixing member. Then, such an outer rotor motor is manufactured using a mold by the following manufacturing method. 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.

By forming a mounting hole in the side edge of the protective portion, the motor can be mounted on the fixing member with a screw or the like.

[0008]

However, in order to integrally mold the stator 3 together with the printed circuit board 7 and the protective portion with resin, it is necessary to apply heat at the time of 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 the case where a protective portion is provided on the exposed portion of the printed circuit board 7 and integrally molded, the printed circuit board 7 and the detection sensor 8 inside the mold have a 10
Heat exceeding 0 ° C will be added. However, the detection sensor 8 such as the photo interrupter is likely to deteriorate in characteristics at a high temperature exceeding 100 ° C. When the characteristics of the detection sensor 8 deteriorate, the operation and life of the detection sensor 8 are affected, and further, there is a problem that a defective product such as the outer rotor motor does not operate normally is generated.

The present invention is provided to solve the above-mentioned problems of the prior art, and an object thereof is to provide an outer rotor motor in which a printed circuit board having electronic parts and a stator can be integrally molded with resin. Is to provide a method for manufacturing the same. More specifically, it is possible to prevent deterioration of characteristics of electronic components such as a position detection sensor due to heat when integrally molded with resin, and to manufacture a high-performance outer rotor motor with a reduced defective product rate. A method of manufacturing a motor is provided.

[0010]

According to a first aspect of the present invention, there is provided a method of manufacturing an outer rotor motor, wherein a stator including a stator coil and an iron core, and an end surface and a circumferential surface are formed in a cup shape to cover the stator. In the method of manufacturing an outer rotor motor, comprising: a rotor cup provided on a substrate; and a printed circuit board having an electronic component on its surface, wherein the stator and the printed circuit board are integrally molded with resin using a mold. When integrally molding the printed circuit board, a space portion having an opening for accommodating the electronic components on the printed circuit board and communicating with the outside of the mold, and a resin for integral molding are prevented from flowing into this space portion. A die having a blocking portion is used, electronic components are arranged in a space of the die, and the stator and the printed circuit board are mounted. While cooling the electronic components through the opening by blowing cooling air into the space portion, characterized in that integrally molded with the printed circuit board and the stator by resin filled in the mold.

In the invention described in claim 1 as described above, since the mold having the blocking portion for preventing the resin for integral molding from flowing into the space of the mold is used, the resin is an electronic component during molding. Never flow into. In addition, a mold having an opening formed so as to communicate with the outside of the mold is used in this space, and cooling air is blown from the opening into the space to integrally mold the electronic components while cooling. Even if it is sometimes heated, the heat transferred from the resin near the electronic component such as near the blocking portion is cooled by the cooling air blown from the opening.

The invention according to claim 2 of the present invention is claim 1
In the method of manufacturing an outer rotor motor described above, the blocking portion is formed of a convex portion formed in a peripheral portion of a position where the electronic component is arranged in a space portion of the mold, and the opening is provided in the blocking portion. And a method for manufacturing an outer rotor motor.

In the above-described invention according to claim 2, since the opening is provided in the blocking portion formed from the convex portion, the resin does not flow into the electronic component at the time of molding, and at the time of molding. Even if it is heated, the electronic component is cooled by the cooling air blown from the opening.

The invention according to claim 3 of the present invention is the invention according to claim 2.
The outer rotor motor manufacturing method described above is characterized in that the convex portion is formed by a member different from the mold.

In the invention according to claim 3 as described above, since the convex portion is formed of a member different from the mold, the convex portion can be installed on the printed board.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment corresponding to the invention described in claims 1 to 3 and an outer rotor motor manufactured based on the invention will be described below with reference to FIGS. 1 to 4. In this embodiment, the same members as those of the conventional technique are designated by the same reference numerals and the description thereof will be omitted.

(1) Configuration of the Embodiment As shown in FIG. 1, an outer rotor motor manufactured by the method for manufacturing an outer rotor motor of the present invention includes a stator 3 integrally molded with a printed circuit board 7 by a resin molding portion. A shaft 1 rotatably supported by the stator 3 and a rotor cup 4 fixed to the shaft 1 and fitted on the outer circumference of the stator 3. A field magnetic pole position detection sensor 8 such as a photo interrupter and a connector 9 are provided on a part of the side of the printed board 7 on the side edge side. In addition, the mold part is composed of a protection part 10 for protecting the printed circuit board 7 and a stator side mold part. The upper surface of the protection part 10 is open on the side of the stator 3 and the recess 7a communicates with the outer peripheral side end surface. Is provided. Further, as shown in FIG. 2, an attachment hole 13 for fixing the outer rotor motor to a fixing member with a screw or the like is formed in the peripheral portion of the protective portion 10.

The method of manufacturing the outer rotor motor of the present embodiment for manufacturing the outer rotor motor as described above is as follows. That is, the rotor cup 4 is integrally molded with resin together with the back yoke 5 and the magnet 6. Then, the stator 3 and the printed circuit board 7
Is integrally molded with resin using a lower mold 14 and an upper mold 15 which are upper and lower molds as shown in FIG. That is, the lower mold 14 corresponds to the formation of the stator side mold portion, and the upper mold 15 corresponds to the formation of the protection portion 10. The upper die 15 is formed with a space for accommodating the detection sensor 8 and the connector 9 on the printed board 7 and electronic parts. In this space, a bushing 12 (corresponding to a blocking portion) which is a member different from the mold is formed. ) Is provided so as to surround the peripheral portion of the position where the back yoke 5 and the magnet 6 are arranged. further,
As shown in FIGS. 2 and 3, the bushing 12 is formed with an opening 11 communicating with the outside of the mold in a freely ventilable manner. The mold is also provided with a corresponding portion of the mounting hole 13 formed in the protection portion 10.

A stator coil 3a and an iron core 3b are mounted on the lower mold 14 of such a mold. Further, the printed board 7 is mounted in the space of the upper mold 15 such that the detection sensor 8 and the connector 9 are located on the stator side mold portion side when integrally molded. Then, resin is flowed into the lower mold 14 and the upper mold 15 of the mold to be connected, and the stator 3 and the printed circuit board 7 are integrally molded. Further, in the vicinity of the opening 11 of the mold, cooling air is blown from the opening 11 toward the detection sensor 8 and the connector 9 in the space by an arbitrary blowing means.

(2) Operation of Embodiment The operation of this embodiment as described above is as follows. That is, even if the resin flows into the mold, the detection sensor 8
The area around the connector 9 is the printed circuit board 7 and the bushing 12.
And because it is surrounded by the mold, the resin does not flow in. Further, the detection sensor 8 and the connector 9 are maintained in the state of communicating with the outside at the opening 11 even if heat exceeding 100 ° C. is applied at the time of integral molding, and air can flow. Furthermore, since cooling air is blown toward the detection sensor 8 and the connector 9 through the opening 11 from the blower provided near the corresponding portion of the opening 11 in the mold,
The thermal energy at the time of integral molding is transferred to the blown cooling air and moves to the outside of the mold.

(3) Effects of the Embodiment The effects of the present embodiment as described above are as follows. That is, since the detection sensor 8 and the connector 9 are separated from each other by the bushing 12 with the resin that becomes hot when integrally molded, they do not come into direct contact with each other. Further, even if the thermal energy of the resin at the time of integral molding is transmitted in the direction of the space, the space 11 in which the detection sensor 8 and the connector 9 are arranged holds the opening 11 that is kept in communication with the outside. Since cooling air is blown into the opening 11, heat energy is transferred to the blown cooling air and moves to the outside of the mold, so that the detection sensor 8 and the connector 9 Temperature is 100
Never exceeds ℃. Therefore, it is possible to prevent characteristic deterioration due to exposure of the detection sensor 8 and the connector 9 to high temperatures, and it is possible to reduce the defective product generation rate. Further, the protection portion 10 enables the outer rotor motor to be attached to the fixing member without damaging the printed circuit board 7 while sufficiently protecting the exposed portion of the printed circuit board 7.

(4) Other Embodiments Note that the present invention is not limited to the above-described embodiments, and the specific shapes of the respective members, the respective mounting positions and methods, etc. can be appropriately changed. is there. For example, the protection unit 1
The opening 11 provided at 0 may be provided with a different opening depending on the position where the detection sensor 8 and the connector 9 are attached, and each opening may be cooled.

Depending on the location where the outer rotor motor is installed, the mounting hole 11 may not be formed in the protective portion 10,
It is also possible to provide a mounting member separately. Furthermore, the blowing means is not limited to one provided on the outside of the die as a separate member, and there is no problem even if it is provided on the outer wall of the die. Further, it is not limited to blowing air from the outside of the mold, and 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. is there. This allows efficient cooling.

[0024]

As described above, according to the method of manufacturing the outer rotor motor of the present invention, when the stator and the printed circuit board are integrally molded, the electronic parts on the printed circuit board are housed and the outside of the mold is communicated. Using a mold having a space having an opening and a blocking part for preventing the resin for integral molding from flowing into the space, electronic components are arranged in the space of the mold, and a stator is provided. And the printed circuit board are mounted, and cooling air is blown into the space from the opening to cool the electronic parts, and the stator and the printed circuit board are integrally molded by the resin filled in the mold, whereby Since the resin does not flow into the space during molding and air can flow from the openings to the electronic components inside the space, it is possible to apply heat during molding. Preventing sexual degradation, it is possible to reduce the defective products incidence. Therefore, it is possible to provide an outer rotor motor having a structure in which a printed circuit board including normal electronic components and a stator can be integrally molded with resin.

[Brief description of drawings]

FIG. 1 is a side view showing an example of an outer rotor motor manufactured based on a method for manufacturing an outer rotor motor of the present invention.

FIG. 2 is a plan view showing a stator of the outer rotor motor of 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 an embodiment of a method for manufacturing an outer rotor motor of the present invention.

FIG. 5 is a side sectional view of the outer rotor motor in a state in which a conventional 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 part 12 ... Bushing 13 ... Mounting hole 14 ... Bottom Mold 15 ... Upper mold

Claims (3)

[Claims] 1. A stator comprising a stator coil and an iron core, a rotor cup having a cup-shaped end face and a circumferential face and provided to cover the stator, and a printed circuit board having an electronic component on the surface. In the outer rotor motor manufacturing method, wherein the stator and the printed circuit board are integrally molded with resin by using a mold, when the stator and the printed circuit board are integrally molded, electronic components on the printed circuit board are housed. A mold having a space part having an opening communicating with the outside of the mold and a blocking part for preventing the resin for integral molding from flowing into the space part is used. Components are arranged, the stator and the printed circuit board are mounted, and cooling air is blown into the space from the opening to cool the electronic component. On the other hand, the outer rotor motor manufacturing method is characterized in that the stator and the printed circuit board are integrally molded with the resin filled in the mold. 2. The blocking section comprises a convex section formed on a peripheral edge of a position where the electronic component is arranged in a space section of the mold, and the opening section is provided in the blocking section. The method for manufacturing an outer rotor motor according to claim 1, wherein: 3. The method of manufacturing an outer rotor motor according to claim 2, wherein the convex portion is formed as a member different from the mold.