JP3386939B2 - Flat type spindle motor, its manufacturing method and its manufacturing apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is suitable for use in a spindle motor for driving a compact disk, etc., and in particular, the perpendicularity between the mounting surface and the output shaft of a flat spindle motor having a double-ended bearing can be easily adjusted. It is designed to be obtained with high accuracy.

[0002]

2. Description of the Related Art A spindle motor for driving an optical medium such as a compact disc is required to have a minimum degree of shaft runout and a very high degree of horizontality of a media chuck table with respect to a mounting surface, that is, a perpendicularity of an output shaft. However, in the case of the so-called double-supported method in which the bearings are arranged in the case and the bracket, respectively, it is necessary to extremely accurately match the fitting between the case and the bracket and the coaxiality of the bearing. Since these members are usually pressed for cost reasons, it is difficult to achieve high precision.
A so-called cantilever system in which two or one long bearings are housed in a cylindrical holder arranged only on one of a case and a bracket is often used.

[0003]

However, when the motor is required to have a low attitude, for example, about 8 mm or less, in the above cantilever system, the length of the output shaft with respect to the dimension between bearings, That is, the media mounting dimension becomes longer, and the tilt of the shaft tends to occur. Therefore, as the motor becomes flatter and lower, the double-supported method must be adopted again, but either the coaxiality between the bearings of the case and the bracket should be pushed to the limit, or the clearance between the bearing and the output shaft should be increased. Otherwise, the flat type can hardly be assembled. Therefore, in addition to the squareness, there is a problem that the output shaft shakes, which is a fatal drawback.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to overcome the above-mentioned problems, and it is possible to easily perform centering while using a double-sided fixed bearing, and at the same time, to the mounting surface of the housing. An object of the present invention is to provide a flat spindle motor that can obtain the squareness of the output shaft with high accuracy, reduce the clearance between the bearing and the output shaft, and reduce the runout of the output shaft, and a manufacturing method thereof. is there.

[0005]

A flat spindle motor which solves the above-mentioned problems is obtained by assembling a bracket (1) with a case (3) having sleeve type bearings (2) arranged as in the first aspect of the invention. Form a housing (H), and the output shaft (7) is formed from at least one end of the housing.
In flat spindle motor rotor (R) formed by turnably supported by the bearing protruding a cabinet
Has a mounting surface (1a) to be mounted on
The mounting part (Ha) with the case (3) is
The bracket (1) that does not come out of the mounting surface
The bracket of is received by the stepped part arranged in the opening and assembled
And the case (3), and the assembly part is intentionally preliminarily formed with play (Hb) and temporarily assembled.
This can be achieved by moving either one of them to align the output shaft and the perpendicularity of the mounting surface of the housing together with the centering, and laser welding (3a) the assembly portion. In order to manufacture the above flat type spindle motor, as shown in claim 2, each case is provided with sleeve type bearings.
Assemble the housing and bracket to form a housing.
The rod with the output shaft protruding from at least one end of the housing
A flat type spin that rotatably supports the rotor on the bearing.
In the manufacturing method of the dollar motor, the case and the bracket
Preliminarily formed to have play in the assembly part
Output shaft prepared in advance after the rotor is stored and temporarily assembled
Mounting surface of the housing is mounted on that Do perpendicular apparatus and
Do not rotate the built-in rotor by energizing
And move the housing on the opposite side to
After determining the perpendicularity between the force shaft and the mounting surface of the housing,
By adopting the process of laser welding the assembly part
Can be achieved . An apparatus for manufacturing the flat spindle motor has sleeves as described in claim 3.
Attach the case and bracket with type bearings to the housing
The housing and exit from at least one end of this housing.
Rotating the rotor with the force axis protruding by the bearing
Supporting flat spindle motor manufacturing equipment
And a bearing portion that rotatably supports the output shaft and the shaft.
The housing mounting part that is perpendicular to the inner diameter of the receiving part, and this housing
Mount the flat spindle motor on
Use the net (11c) to temporarily hold and bracket
A member (11) for producing a perpendicularity of the mounting surface 1a of the grate (1)
And means for preventing movement on the housing side (11
d) and rotating the built-in rotor by energizing
Means for moving the housing and the hand that moves the opposite side of the housing
Lay the step (12) and the assembly part of the case and the bracket.
This can be achieved by using a means (S) for welding .

According to the means for solving the problems described in claim 1, since the case and the bracket are formed so that the assembling portion is intentionally provided with a play, the space between the shaft and the bearing can be moved by temporarily moving either one after the temporary assembling. Even if the clearance is extremely small, the bearings can be easily aligned with each other, and then the assembly portion is fixed by means other than pressure deformation, so that the assembly can be assembled without misalignment. According to the manufacturing method of the present invention as set forth in claim 2, even if the clearance between the shaft and the bearing is extremely small, it is possible to easily perform the centering, and then the assembly portion is subjected to means other than the pressure deformation. Since they are fixed, the perpendicularity between the shaft and the mounting surface of the housing can be obtained without causing misalignment. When the manufacturing apparatus of the present invention as set forth in claim 3 is used, even if the clearance between the shaft and the bearing is extremely small, the housing on the side opposite to the mounting side can be moved, so that centering can be easily performed and the output shaft can be easily adjusted. Since the bearing that supports the bearing and the housing mounting surface are at a right angle, an extremely accurate squareness can be obtained, and since the case and bracket are not deformed by pressure as a fixing means, centering and squareness are maintained. Can be completed as it is.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a structure adopted in a face-to-face coreless flat type spindle motor as an embodiment of the present invention will be described based on a sectional view of a main part shown in FIG. In the figure, reference numeral 1 denotes a bracket having an upper surface serving as a mounting surface 1a to be mounted on a cabinet (not shown) or the like, and an oil-impregnated bearing 2 is fitted into a burring hole 1b arranged in the center and mounted on the outside thereof. Screw holes 1c, 1c are provided. This bracket 1
The outer periphery of is formed to be thinner than the plate thickness at the step portion 1d, and the opening edge 3a of the shallow cylindrical case 3 having a bottom is assembled to form the housing H. Assembly part H of this housing H
As for the a, the play Hb is intentionally taken into consideration as shown in the enlarged view.

A bag-shaped bearing hole 3 is provided at the bottom of the case 3.
b is provided and a bearing 2 similar to the bracket 1 is fitted. At the bottom of the case surrounding the bearing 2, a pair of brushes 4 and 4 are planted via a brush base 5 formed by resin molding integrally with the case, and a ring-shaped magnet 6 is placed. To be done. R is a plurality of air-core coils R1
.., R2, ... Are integrally formed of synthetic resin J together with the output shaft 7 and are arranged with a gap between the bracket 1 and the magnet 6 and through the output shaft 7 the bearing 2 2 is rotatably supported. The rotor R is further provided with a cylindrical commutator 8
Is arranged, and the free ends of the brushes 4 and 4 are slidably contacted to receive electric power. In the figure, Ra is a suction plate for urging the rotor R toward the magnet 6 side, and this urging force is a receiving plate 3c on which the base end of the output shaft 7 is pivotally supported.
Can be accepted by.

Since the bracket 1 constitutes a magnetic circuit of the magnet 6, it is made of a magnetic material. Therefore, by mounting the case 3 with the rotor R built therein, even if there is a play Hb in the mounting portion Ha, the magnet is formed. It can be temporarily assembled with a magnetic force of 6. Then, after the centering is completed, the assembled portion is fixed by welding or adhesion to be described later so as not to be deformed under pressure, and the assembly is completed.

Next, a manufacturing method and a manufacturing apparatus for completing the flat type spindle motor having such a structure will be described with reference to the cross-sectional view of the main part shown in FIG. In the figure, 11
Is a part of a device that makes a perpendicularity between the mounting surface 1a of the bracket 1 that constitutes the housing H and the output shaft 7. The bearing 11a that rotatably supports the output shaft is provided inside the bearing 11a. A housing mounting portion 11b and a temporary holding neodymium magnet 11c which are orthogonal to each other are arranged. A protrusion 11d for preventing movement of the bracket 1 is provided on a part of the housing mounting portion 11b, and a plurality of laser spot welding fiberscopes S are arranged on the outside. On the other hand, 12 is a part of a device for moving the case 3 back and forth and left and right, and a part 11 of the device.
A non-round hole 12a slightly eccentric with respect to
By fitting a case into the non-round hole and rotating the case with a belt V or the like, the case 3 has a motion of slightly rotating in the front, rear, left, and right directions.

Now, the rotor R is attached to the bracket 1 and the case 3.
The output shaft 7 is housed in the housing H consisting of
As shown in FIG. 3, the fitting surface of the bracket is fitted to the bearing portion 11a of No. 1 and the holding surface of the bracket is temporarily held by the holding neodymium magnet 11c using the attraction force as shown in FIG. . After that, while applying a low voltage to the external lead-out terminal T,
When the device 12 is fitted into the case 3 and rotated, the current sharply decreases when the centering is obtained. Therefore, the case 3 is stopped moving at this position. A schematic diagram of this movement positional relationship is shown in FIG.
As shown in. That is, the bearing 2 on the case 3 side
Even if is shifted as shown by the imaginary line at the beginning, the case 3 can be adjusted to the front, rear, left and right to obtain the alignment at the position indicated by the solid line. The assembling portion Ha is spot-welded by driving a laser device (not shown) while maintaining this state. At this time, the welded portion does not protrude above the bracket mounting surface 1a beyond the step 1d. After that, by pushing the tip of the output shaft with the protrusion pin P, the main body is removed from the device 11 to complete the process.

With such a manufacturing method and manufacturing apparatus,
Even if the centers of the bearings 2 and 2 of the bracket 1 and the case 3 are deviated from each other, alignment can be performed, and at the same time, the perpendicularity between the mounting surface 1a of the bracket 1 and the output shaft 7 can be obtained with extremely high accuracy.

[0013]

Other Embodiments In the above-described embodiments, the bracket side is used as the mounting surface, but the case and the bracket may be assembled in reverse, and the case side may be used as the mounting surface. Further, although the spot welding by the laser is shown as the fixing means of the assembling part, the entire circumference may be adhered by using an ultraviolet curable adhesive as a means other than the pressure deformation. Furthermore, in the above-described embodiment, the protrusion 11d for preventing the movement of the bracket 1 may not be inserted in the mounting hole 1c, but a guide discard hole may be separately provided and fitted therein. Further, the application of the configuration of the present invention can be applied to a double shaft type motor in which the output shaft projects from both ends of the housing.

[0014]

As described above, according to the double-supported flat spindle motor of the present invention, and the manufacturing method and manufacturing apparatus thereof, the case and the bracket are formed in advance so that the assembly is intentionally provided with a play. Despite the use of bearings, centering is easy, and at the same time, the squareness of the output shaft with respect to the mounting surface of the housing can be obtained with high accuracy. Furthermore, the clearance between the bearing and shaft can be reduced to reduce runout of the output shaft. Therefore, it is extremely useful.

[Brief description of drawings]

FIG. 1 is a partially enlarged cross-sectional view of a part of an embodiment of a flat spindle motor of the present invention.

FIG. 2 is a cross-sectional view of a main part of the motor manufacturing apparatus.

FIG. 3 is a cross-sectional view of essential parts in which the motor is assembled in the manufacturing apparatus.

FIG. 4 is a schematic diagram of a positional relationship of operations for obtaining the centering of the motor.

[Explanation of symbols]

1 bracket 1a Mounting surface 2 bearings 3 cases H housing Ha assembly section Hb play 4 brushes 5 brush base 6 magnets R rotor 7 Output shaft 11, 12 Part of manufacturing equipment 11a bearing 11b Housing mounting part 12a Non-round hole

Claims (3)

(57) [Claims] 1. A rotor having a housing (H) constructed by assembling a case (3) having a sleeve type bearing (2) and a bracket (1), and an output shaft (7) protruding from at least one end of the housing. In a flat type spindle motor in which (R) is rotatably supported on the bearing , mounting to be mounted on a cabinet (not shown) or the like
An assembly part having a surface (1a) and assembled with the case (3)
Bracket that prevents (Ha) from coming out of the mounting surface
(1) and the step with this bracket in the opening
A case (3) for receiving and assembling, the assembly part is formed beforehand so as to have a play (Hb) intentionally and temporarily assembled , and either one is moved to align the output shaft and the housing. A flat spindle motor in which the perpendicularity of the surface is obtained and the assembly portion is laser-welded (3a). 2. A case in which sleeve type bearings are arranged, respectively.
And bracket to assemble the housing,
The rod with the output shaft protruding from at least one end of the housing
Flat spind bearing that is rotatably supported on the bearing.
Of the case and bracket in the manufacturing method of
So that the assembly part is intentionally formed with play.
Output shaft prepared in advance after the rotor is stored and temporarily assembled
And the housing mounting surface is at a right angle.
Do not rotate the built-in rotor by energizing
Move the opposite side of the housing to move it out with alignment.
After determining the perpendicularity between the force shaft and the mounting surface of the housing,
A method for manufacturing a flat spindle motor , characterized in that the assembly portion is laser-welded . 3. A case in which sleeve type bearings are arranged, respectively.
And bracket to assemble the housing,
The rod with the output shaft protruding from at least one end of the housing
The flat type bearing rotatably supported by the bearing
Rotating the output shaft in a pindle motor manufacturing device
A bearing that can be freely supported and a hub that is perpendicular to the inner diameter of this bearing.
The housing mounting part and this housing mounting part
Use a flat spindle motor with a magnet (11c).
For temporary holding and mounting surface of bracket (1)
A member (11) for producing a squareness of 1a, and further a housing
Means to prevent side movement (11d) and to energize
More built-in means for rotating the rotor and anti-attachment part
(12) for moving the housing on the side, and the case
Means for laser welding the assembly part of the bracket (S)
An apparatus for manufacturing a flat spindle motor, including: