JPH0937534A - Structure and manufacturing method in outer rotor-type radial flat brushless dc motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a magnetic pole structure thin and simple, by joining conductor by solder with a pad on a coil wiring board while a fixing arm for a conductor is a bobbin is put firmly on a coil wiring board. SOLUTION: A salient pole of a bobbin 1 is inserted in a salient pole through hole on a frame side in the bobbin 1 with wiring around it. In this inserting step, an arm part 6 is put firmly on a coil wiring 19 mounted on a yoke. Then, a conductor 14 mounted under a conductor fixing arm 8 is put firmly on the coil wiring board 19 so that a laminated structure of a yoke 16 and the coil wiring board 19 are put firmly between the arm 6 and a positioning arm 10. At this time the conductor 14 is put on a connection pad projected from a window of the coil wiring board 19 or on a position along the side face thereof. In this state, the wiring and the pad of the coil wiring board 19 can be joined by solder. The structure of a stator magnetic pole is simplified by thinning off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator structure of an outer rotor type radial flat brushless DC motor having a structure in which a bobbin around which a coil is wound is inserted into a salient pole portion of the stator, and a manufacturing method thereof.

[0002]

2. Description of the Related Art For example, a floppy disk driver used as an auxiliary storage device of a personal computer uses a flat outer rotor type radial flat brushless DC motor for driving a floppy disk. In this type of outer rotor type radial flat brushless DC motor, the salient poles of the stator protrude in the radial direction around the rotation axis, and the tip of the salient pole faces the rotor magnet and rotates the rotor magnet. Since the pole teeth extend in the direction and have a T-shape, the winding portion of the stator coil can be thinly formed, but the bobbin cannot be inserted into the salient poles of the stator. Since the salient poles of are directly wound, this process required a lot of man-hours. In addition, if even one slot is defective during winding, the entire stator structure will be defective, which is a major factor in reducing the yield.

In order to avoid the above-mentioned inconvenience, pole teeth are removed from the tip of the salient pole of the stator, the salient pole is formed in a rod shape, and the coil is wound on a bobbin in a separate step to form a stator coil. The bobbin of this stator coil is inserted and mounted in each salient pole of the stator.

[0004]

Considering the number of manufacturing steps of the motor, assembling the stator structure including the winding process requires the most time, and rationalization is required. In particular, the wiring of the coil wound around the bobbin inserted in each salient pole requires much labor. That is, conventionally, as shown in FIG. 9, the salient poles 102 protruding from the yoke portion 101 in the radial direction are used.
The bobbin 103 is fitted in. A coil 104 is wound around the bobbin 103, and an end of the coil 104 is entangled with a protrusion 105 standing on the base of the bobbin 103, and then penetrates a collar portion 106 of the bobbin and is erected on this. Terminal rod 1
It is soldered to the base of 07. The bobbins 103 that have completed soldering are fitted to the salient poles 102, respectively.

Then, a ring-shaped flat plate-shaped printed circuit board 109 is placed on the base of the bobbin 103, and the tip of a terminal rod 107 standing from the flange 106 of the bobbin 103 is inserted into a hole 110 formed in the ring-shaped printed circuit board 109. , The printed wirings 111 provided on the printed circuit board 109 are soldered, the coils 104 are star-connected by the printed wirings 111, and lead wires 112 for wiring to the outside are led out from the printed circuit board 109. The stator assembly thus configured covers the soft iron plate with an insulating film, and is fixed to a substrate on which printed wiring, electronic components required for driving the motor, and the like are mounted. FIG. 10 is a cross-sectional view of an outer rotor type radial flat brushless DC motor formed flat to drive the assembled floppy disk. In FIG. 10, reference numeral 121 denotes a substrate that constitutes a floppy disk drive device, and is made of a ferromagnetic material such as iron. A plurality of holes 122 are formed in the substrate 121, and a fixed base 123 made of synthetic resin is fixed by injection molding with the holes 122 as mounting portions. A cylindrical bearing tube 124 is fixed to the center of the fixed base 123. At the bottom of the bearing sleeve 124, a pivot 125 that supports the bottom surface of the bearing described later is provided. Reference numeral 127 is a rotating disk that constitutes a rotor and rotates a floppy disk, and has a thin circular dish shape. A rotating magnetic pole 129 made of a ring-shaped permanent magnet is fixed inside the outer circumference 128 of the rotating disk 127. Also the outer circumference 12
A speed detection permanent magnet 130 for detecting the rotation speed of the rotating disk 127 is fixed to the lower part of the position 8. The rotating magnetic pole 129 composed of the permanent magnet is made of a plastic magnet and has a ring shape. A plurality of permanent magnets are formed on the rotating magnetic pole 129 by magnetization. These permanent magnets are magnetized in the diameter direction of the rotary magnetic pole 129, and the magnetic pole directions of these permanent magnets are adjacent to each other and reversed.
The rotating disk 127 assembly including the rotating magnetic pole 129 constitutes the rotor 126.

A rotating shaft mounting plate 131 made of metal is fixed to the center of the rotating disk 127.
A rotary shaft 132 is fixed to the center of 1. The rotating shaft 132 is rotatably supported by a cylindrical bearing tube 124. The rotary disk 127 is provided with 133, from which the drive pin 13 to be fitted with the floppy disk is formed.
4 are protruding.

In the above-mentioned conventional apparatus, soldering of the bobbin to the terminal rod 107 at two locations is performed, and each bobbin is inserted into the salient pole 102 before the fixed magnetic pole is assembled. Soldering the rod 107 and two soldering steps are required. Moreover, this process cannot be performed by one soldering operation. Moreover, the collar portion 10 of each bobbin
6, the terminal rod 107 must be embedded, which increases the bobbin processing cost. In addition, since it is necessary to solder the coil end to the terminal rod 107 at the lower part and solder it to the printed circuit board at the upper part, it is not possible to make this short, which may reduce the thickness of the stator structure. Have difficulty.

[0008]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned inconvenience, and an object thereof is to provide a stator magnetic pole structure in a flat outer rotor type radial flat brushless DC motor. It is an object of the present invention to provide a structure and a manufacturing method in which the structure can be formed as thin as possible and the structure can be easily formed, and the manufacturing process can be significantly shortened as compared with the conventional product.

In order to achieve the object of the present invention as described above, the present invention is an outer rotor type radial in which a bobbin having a winding for each salient pole is inserted in the salient pole of a stator made of a magnetic material. In a stator structure of a flat brushless DC motor, a ring-shaped yoke portion connecting each salient pole, a wire connecting each stator coil, and a pad for soldering an end portion of the stator coil are provided at predetermined positions. Then, the coil wiring board arranged on the yoke and a lead wire fixing arm that rides on the coil wiring board are provided at the tip, and the tip of the wound lead wire is wired below the lead wire fixing arm. An outer rotor type radial flat brushless, characterized in that the conducting wire and the pad of the coil wiring board are solder-connected in a state in which the conducting wire fixing arm of the bobbin rides on the coil wiring board. Providing a stator structure of C motor.

The coil wiring board is formed in a thin plate and has wirings for connecting the stator coils and pads for soldering the ends of the stator coils at predetermined positions. The coil wiring board has wiring, which is formed on the surface of the insulating film provided on the upper surface of the yoke, for connecting each stator coil and a pad for soldering the end portion of the stator coil at a predetermined position. ing. Further, the insulating film covering the conductor wire is an insulating film in which the insulation is dissolved by heat treatment.

The present invention is also directed to a method of manufacturing a stator of an outer rotor type radial flat brushless DC motor in which a bobbin wound on each salient pole portion is inserted into a salient pole portion of a stator made of a magnetic material. , The step of inserting the bobbin wound the conductor to the salient pole protruding in the radial direction from the yoke where the coil wiring board is formed on the upper surface of the yoke, and fixing the bobbin conductor when the bobbin is inserted into the salient pole An outer process comprising: a step of locating a conductive wire crawling on a lower surface of an arm in the vicinity of a connection pad of a coil wiring board; and a step of locally heating the vicinity of the connection pad to solder the conductive wire to the connection pad. Rotor type radial flat brushless DC
The present invention also provides a method for manufacturing a motor stator. .

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A bobbin wound with a conductive wire is inserted into a salient pole protruding in a radial direction from a yoke having a coil wiring board formed on an upper surface of the yoke. When the bobbin is inserted into the salient pole, the conducting wire laid on the lower surface of the conducting wire fixing arm of the bobbin is positioned near the connection pad of the coil wiring board. The conductor is soldered to the connection pad by locally heating the vicinity of the connection pad.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to the drawings. 1 is a side sectional view showing a bobbin of a flat outer rotor type radial flat brushless DC motor according to the present invention, FIG. 2 is a top view thereof, and FIG. 3 is a bottom view thereof. In FIG. 1, a bobbin 1 has a body portion 2 having a quadrangular cross-section and a quadrangular cylinder in the center. A hollow salient pole insertion hole 3 having a quadrangular cross section is formed in the central portion of the body portion 2. A collar portion 4 is provided at one end of the body portion 2. On the upper side of the other end of the body portion 2, a conductor holding portion 5 that entangles the ends of the coil is formed. The conductor holding portion 5
Has a wire-entangled column 7 extending upward from the arm 6.

As is apparent from FIG. 2, conductive wire fixing arms 8, 8 extend horizontally on both side surfaces of the arm portion 6. Small tips 9 are formed at the tips of the wire fixing arms 8 so that the wire is sandwiched between them. As is apparent from FIGS. 1 and 3, a positioning arm 10 is provided on the lower side of the body portion 2, and a positioning protrusion 11 is provided on the lower surface of the positioning arm 10. A collar 12 is formed on the other end of the body portion 2, and notches 13 for sandwiching the conductor wire are formed on both upper sides of the collar 12.

The process of winding the wire around the bobbin 1 will be described. As shown in FIG. 4, the end portion 1 of the conducting wire 14 at the beginning of winding
After winding 5 around the root of the conductor-entangled column 7, the conductor 14
Is fitted into the recess 9 of the conductor fixing arm 8, and the conductor 14 is turned below the conductor fixing arm 8 and fitted into the notch 13 of the collar 12. Then, the conducting wire 14 is wound around the body portion 2 of the bobbin 1 to wind up the coil 16. The end portion of the coil 16 wound up is fitted into the other notch 13 of the collar 12, turned to the lower side of the other wire fixing arm 8, fitted into the recess 9, and entangled with the wire entanglement column 7 and then cut. Finish the coil winding work. In this operation, for safety, it is preferable that the winding start end and the winding end end of the conductor wire 14 are not entangled with each other when the conductor wire entanglement column 7 is wound.
The reason for this is to prevent each other from short-circuiting by any chance. Since the conductive wire 14 is coated with a synthetic resin film such as polyurethane, it is unlikely that the insulation will be broken and the two will be short-circuited even if they are wound repeatedly.

Next, a method of assembling the stator structure will be described. As shown in FIG. 5, a disk-shaped coil wiring board 19 is placed on the yoke 16 of the iron core 18 made of a laminated plate provided with salient poles 17 in the radial direction from the circumference of the yoke 16. At this time, the circular hole 20 formed in the center of the yoke 16 and the central opening 21 of the coil wiring board 19 are aligned with each other, and the key groove of the circular hole 20 and the key groove 2 provided at the week edge of the central opening 21.
2 are aligned with each other, and the coil wiring board 19 is fixed on the yoke 16 by an appropriate means.

As shown in FIGS. 6 and 7, the coil wiring board 19 is provided with a ring-shaped insulating substrate 23 made of epoxy glass on the bottom surface side, that is, the side in contact with the yoke 16, on which the stator. Wiring 24 for connecting each coil is printed. Insulating substrate 23 having wiring 24 on the surface
A resist film 25 is attached on the top surface. Windows 26 are opened in the resist film 25.
The connection pad 27 is exposed. This connection pad 2
7 consists of solder swell.

Next, as shown in FIG. 4, the bobbin 1 of the salient pole is inserted from the salient pole insertion hole 3 side of the collar 12 side of the bobbin 1 around which the conducting wire is wound. In this insertion process, first, the arm portion 6 rides on the coil wiring board 19 placed on the yoke 16. Next, the lead wire 14 that is turned around the lead wire fixing arm 8
Ride on the coil wiring board 19, and as shown in FIG. 8, the arm portion 6 and the positioning arm 10 are connected to the yoke 16 and the coil wiring board 1.
The laminated structure of 9 is sandwiched. At this time, lead wire 1
4 is located on the connection pad 27 protruding from the window 26 of the coil wiring board 19 or along the side surface thereof.

When the bobbins 1 each having a coil wound around each salient pole 17 are mounted in this manner, the connection pads 27
The vicinity of the contact between the conductor 14 and the conductor 14 is heated by a method such as local high-frequency heating to partially melt the insulating film of the conductor 14 by heat, and the conductor 14 and the connection pad 27 are electrically soldered. -Mechanically connect to complete assembly of the stator assembly. The assembled stator assembly is placed on the substrate 121 that constitutes the floppy disk drive, and the positioning protrusion 11 provided on the lower side of the positioning arm 10 is inserted into the positioning hole of the substrate 121. Positioning protrusion 1
The stator assembly is fixed to the substrate by using an appropriate means such as melting the tip of the stator 1.

In the above-described embodiment, a disk-shaped coil wiring board using the printed wiring method is separately provided, and this is placed on the yoke so that the arm portion 6 and the positioning arm 10 have the yoke 16 and the coil wiring board. Although it was configured to sandwich the laminated structure of 19,
An insulating film is provided on the surface of the yoke, and wiring 24 for connecting each coil of the stator is printed on the upper surface of the yoke, and a resist film 25 is adhered on the wiring 24.
The windows 26 may be opened so that the connection pads 27 are exposed from the windows 26. With such a configuration, the thickness of the motor can be made thinner than that of the above-mentioned embodiment. Further, such a coil wiring board can be formed on both front and back surfaces of the yoke.

The present invention can be applied not only to a brushless DC motor, but also to all motors or generators that form a salient pole portion using a soft magnetic core, and of course both inner rotor / outer rotor types. It is obvious that it can also be applied to.

[0022]

As described above, according to the present invention, a flat outer rotor type radial flat brushless DC motor does not require a terminal rod for fixing the coil wiring board to the bobbin, and therefore the stator The magnetic pole structure can be made as thin as possible. Moreover, the bobbin around which the coil is wound is inserted into the salient pole, and the coil and the connection pad of the coil wiring board can be connected by soldering only by locally heating, so that the structure can be easily formed and the manufacturing process can be performed conventionally. It can be shortened significantly compared to the product. Further, according to the present invention, there is an advantage that the outer rotor type radial flat brushless DC motor can be automatically assembled by the assembly machine.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a bobbin of a flat outer rotor type radial flat brushless DC motor according to the present invention.

FIG. 2 is a top view showing a bobbin of a flat outer rotor type radial flat brushless DC motor according to the present invention.

FIG. 3 is a bottom view showing a bobbin of a flat outer rotor type radial flat brushless DC motor according to the present invention.

FIG. 4 is a perspective view of a bobbin.

FIG. 5 is a perspective view of a fixed magnetic pole.

FIG. 6 is a perspective view of a coil wiring board.

FIG. 7 is a cross-sectional view of a coil wiring board.

FIG. 8 is a partial cross-sectional view showing a bobbin insertion position.

FIG. 9 is a partial perspective view showing a conventional stator structure.

FIG. 10 is a cross-sectional view of a conventional example.

[Explanation of symbols]

 1 bobbin 2 body part 3 salient pole insertion hole 4 collar part 5 wire holding part 6 arm part 7 ... Conductor entangled column 8 ... Conductor fixing arm 9 ... Recess 10 ... Positioning arm 11 ... Positioning protrusion 12 ... Tsuba 13 ･ ･ ･ Cut 14 ･ ･ ･ Conductor 15 ･ ･ ･ End 16 ･ ･ Yoke 17 ･ ･ ･ Salient pole ･ 18 ･ Iron core ･ 19 ･ Coil Wiring board 20 ... Circular hole 21 ... Central opening 22 ... Key groove 23 ... Insulating substrate 24 ... Wiring 25 ... Resist film 26 ... window 27 ... connection pad 101 ... yoke portion 102 ... salient pole 103 ... bobbin 104 ... coil 105 ... Protrusion 106 ... Collar part 107 ... Terminal bar 108 ... Soldering 109 ... Printed circuit board 110 ... Hole 111 ... Printed wiring 121 ... ... substrate 122 ... hole 123 ... fixed base 124 ... bearing tube 125 ... pivot 126 ... rotor 127 ... rotating circle Plate 128 ... Outer periphery 129 ... Rotating magnetic pole 130 ... Position detecting permanent magnet 131 ... Rotating shaft mounting plate 132 ... Rotating shaft 133 ... -Hole 134-Drive pin 135-Spring plate 136-Mounting base 137-Arm part 138-Drive IC 131-Stator Magnetic pole 143 ... Protrusion 144 ... Bobbin

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsutoshi Suzuki 1743 Asana-cho, Iwa-gun, Shizuoka Prefecture Minebea Co., Ltd. Development Technology Center (72) Inventor Masaaki Inagaki 1743 Asana-cho, Iwata-gun, Shizuoka Prefecture -1 Minebea Co., Ltd. Development Technology Center

Claims (5)

[Claims] 1. A stator structure of an outer rotor type radial flat brushless DC motor in which a bobbin having a winding for each salient pole portion is inserted into the salient pole portion of a stator made of a magnetic material. A ring-shaped yoke portion, wiring for connecting each stator coil and a pad for soldering the end portion of the stator coil at a predetermined position, and a coil wiring board arranged on the yoke, and a tip. And a bobbin in which a leading end of the wound conducting wire is wired below the conducting wire fixing arm, and the conducting wire fixing arm of the bobbin is mounted on the coil wiring board. A stator structure for an outer rotor type radial flat brushless DC motor, characterized in that a conductor wire and a pad of a coil wiring board are solder-connected while riding on a wiring board. 2. The coil wiring board is characterized in that it has a thin plate-shaped wiring for connecting each stator coil and a pad for soldering an end portion of the stator coil at a predetermined position. The stator structure of the outer rotor type radial flat brushless DC motor according to claim 1. 3. The coil wiring board is provided with a wiring for connecting each stator coil and a pad for soldering an end portion of the stator coil, the wiring being formed on the surface of an insulating film provided on the upper surface of the yoke. The outer rotor type radial flat brushless D according to claim 1, characterized in that
C motor stator structure. 4. The stator structure for an outer rotor type radial flat brushless DC motor according to claim 1, wherein the insulating film covering the conductor wire is an insulating film which is melted by heat treatment. 5. A method for manufacturing a stator of an outer rotor type radial flat brushless DC motor, wherein a bobbin having a winding for each salient pole portion is inserted into the salient pole portion of the stator made of a magnetic material, and the upper surface of the yoke. The step of inserting the bobbin wound the conductor wire to the salient pole protruding in the radial direction from the yoke with the coil wiring board formed on it, and the step of inserting the bobbin into the salient pole, the bottom surface of the conductor fixing arm of the bobbin. An outer rotor type radial flat, comprising: a step of positioning the crawled conductor near the connection pad of the coil wiring board; and a step of locally heating the vicinity of the connection pad to solder the conductor to the connection pad. A method for manufacturing a stator of a brushless DC motor.