JP3530037B2 - Brushless motor with resin turntable - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CD-ROM,
The present invention relates to a brushless motor including a resin turntable suitable for driving a medium such as a DVD-ROM. 2. Description of the Related Art Conventionally, as a brushless motor for driving a medium such as a CD, as shown in FIG. 4, a turntable for mounting a medium is formed by cutting free-cut brass on one side of a cylindrical rotor case K. T, a rotor R having a magnet M on the other side, a shaft S for supporting the rotor R, a housing H for supporting the shaft S, and a housing H Some include a stator ST for driving the rotor R. [0003] However, such a media mounting turntable T is formed by cutting brass, so that the cost and the labor for mounting the media become problems. In particular, since a medium such as a CD-ROM is required to have a high degree of perpendicularity to drive a medium, the media mounting turntable T may be mounted on the shaft and then cut with reference to the shaft for use. However, even brass, which is relatively easy to cut, has problems such as shaft idling due to metal. Recently, as a countermeasure for cost, a device using a turntable JT made of resin has appeared as shown in FIG. However, in the case of using such a resin turntable JT, there is a problem of dimensional accuracy and a problem that a thin leaf spring B for holding down the inner diameter portion of the medium is required for securing the medium holding strength. An object of the present invention is to make it possible to perform functions without using an expensive turntable formed by cutting free-cutting brass or the like, thereby making it advantageous in terms of cost. The object of the present invention is to eliminate the need to use a thin leaf spring or the like to hold down the inner diameter portion of the medium. [0005] To solve the above problems [Means for Solving the Problems], as shown in claim 1, to function as a resin turntable upper side of the rotor case (6)
The media mounting portion (8) is formed integrally with the
Start-up unit (8a) for centering media disks
Is formed integrally with the media mounting portion with resin,
Magnet (7) arranged inside the
Rotor consisting of a shaft (5) pressed into the rotor case
(R), a resin-made shaft holder (3) for rotatably supporting the shaft via a bearing, and integrally forming the shaft holder.
The stator base (1), distribution on the outer circumference of the shaft holder
And a stator for driving the rotor, further
In addition, the rotor has a position on the outer periphery of the rising portion (8a).
A molding die insertion opening (8b) is provided in the
Less media holding through the mold insertion opening (8b)
And one media chuck spring portion (8c) is
This can be achieved with the same resin integrally formed with the hoisting portion (8a) . According to the first aspect of the present invention, since there is no need to specially prepare a spring portion for the media chuck, cost and labor for mounting can be reduced, and a media mounting member integrated with a resin functioning as a turntable. The media disk can be mounted by the part, the media disk centering can be performed by the rising part (8a) integrally with the medium mounting part, and the spring part (8c) for the media chuck is integrated with the rising part by the molding die insertion opening. Can be formed. Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a main part showing a configuration of a radial gap type cored type as a first embodiment of a brushless motor provided with a resin turntable of the present invention,
FIG. 2 is an enlarged sectional view of a main part of the motor. In FIG. 1, reference numeral 1 denotes a stator base made of a thin stainless steel plate or the like, on which a circuit board 2 made of a glass cloth epoxy plate is arranged, and three supporting bones are left with a bridging portion 1a at the center. The shaft holder 3 is formed by raising the piece 1b # and integrally molding the support bone piece 1b # with a highly slidable resin. A stator core 4 formed by winding an armature coil 4b # around a plurality of salient poles 4a # is fixed to the outer periphery of the shaft holder 3 by bonding, welding or the like.端末 terminal 4
c is soldered to a predetermined pattern of the circuit board 2. On the other hand, the rotor R comprises a shaft 5 directly rotatably mounted on the shaft holder 3, a rotor case 6 mounted by press-fitting the shaft 5, and the stator core inside the rotor case 6. 4 salient poles 4a
A ring-shaped rubber magnet 7 is formed by curling and pressing and fixing a plate-like material so as to face through a radial gap in ‥‥, and a resin-made media mounting member serving as a turntable is provided above the rotor case 6. The part 8 is formed integrally. The circumference of the axis of the media mounting portion 8 is slightly raised so as to be slightly smaller than the inner diameter of the media to be centered, and is formed on the outer periphery of the rising portion 8a through the molding die insertion opening 8b. The hanging media chuck spring portion 8c is integrally formed of the same resin. In this case, it is desirable to arrange the media chuck spring portions 8c equally in three pieces, but only one piece may be used. The outer circumference of the spring portion 8c is slightly larger than the inner diameter of the media disk, and is pressed and held with good spring properties. Then, after such a rotor case 6 is press-fitted into the shaft, as shown in FIG. 2, the media mounting portion 8 is cut at a portion indicated by an imaginary line with respect to the shaft to obtain the shaft perpendicularity. It was done. [0010] It is desirable to use a relatively hard and elastic resin for a high-speed rotating medium for such a resin turntable. According to the present invention, as described above, the spring portion for the media chuck does not need to be specially prepared, so that the cost and the labor for mounting can be reduced, and the resin functioning as a turntable is integrated with the resin. A media disk can be placed on the media placing portion, and the starting portion (8) is integrated with the media placing portion.
Media disk centering can be performed by a), and the spring portion for media chuck (8c) can be integrally formed by the molding die insertion opening (8b). Further, since the media mounting portion is made of resin, it can be easily cut, and the degree of perpendicularity to the shaft can be sufficiently secured.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a principal part showing a configuration of a radial gap type cored type as a first embodiment of a brushless motor provided with a resin turntable of the present invention. FIG. 2 is an enlarged sectional view of an essential part of a main member of the motor. FIG. 3 is a sectional view of a main part of a brushless motor provided with a conventional turntable. FIG. 4 is a sectional view of a main part of a brushless motor provided with a conventional resin turntable. [Description of Signs] 1 Stator base 1a Bridge portion 1b Brace piece 2 Circuit board 3 Axis holder 4 Stator 4a Salient pole 4b Armature coil 5 Axis 6 Rotor case 7 Ring-shaped rubber magnet 8 Media mounting portion 8a Start-up portion 8b Mold insertion opening 8c Spring for media chuck

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G11B 17/022-17/038

Claims (1)

(57) media mounting unit that functions as a resin turntable (8) is integrally on the side of the Claims 1 rotor casing (6)
And media disk centering
(8a) is made of resin and is mounted on the
A magnet formed integrally and arranged inside the rotor case
A net (7) and a shaft press-fitted into the rotor case
And (5) a rotor (R) comprising:
A resin-made shaft holder (3) rotatably supported through
A stator base (1) in which the shaft holder is integrally formed ;
By disposing the outer periphery of the shaft holder and a stator for driving the rotor, further, the rise in the rotor
At the position on the outer periphery of the part (8a), the molding die insertion opening (8b) is
At least one media chuck spring portion (8c) for holding the media through the molding die insertion opening (8b ) is integrally formed with the rising portion (8a). A brushless motor with a resin turntable made of resin.