JPH0510902B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for fixing a holder to the shaft of a spindle motor, and more particularly, to a method for fixing a holder that improves mechanical accuracy during holder assembly.

<Prior Art> For example, in a magnetic disk device, when a magnetic disk (hereinafter referred to as disk) is fixed to a spindle shaft, it is necessary to fix it so that there is no eccentricity or surface wobbling.

FIG. 3 is a sectional view showing the fixing direction of a conventionally used magnetic disk.

In Fig. 3, 1 is a spindle motor, and 2 is a motor shaft (hereinafter referred to as shaft).
It is. 3 is a holder whose upper surface A part is processed flat, and has a diameter of large and small perpendicular to this plane A part,
An adapter part B is formed with a thread formed at its tip, and a hole provided in the center of a holder passing through the adapter part B is press-fitted into the shaft 2. 4 is a disk placed on the top surface of the holder 3;
It is fitted into the large diameter side of the adapter part B of the holder.
Reference numeral 5 denotes a tapered guide having a tapered portion 5a at one end.The tapered portion is inserted into the small diameter side of the adapter portion B of the holder 3, and the tip of the tapered portion 5a is fixed in a state pressing against the inner diameter of the disk 4. As a result, the disk 4 is brought into close contact with the flat surface A of the holder 3 and is fixed at the center of the shaft 2. Nut 6 is screwed onto the taper guide 5 from above and serves to fix the taper guide.

<Problems to be Solved by the Invention> In the above configuration, when the holder 3 is press-fitted into the shaft 2, the shaft 2 is bent due to the press-fitting, and the surface runout and eccentricity of the holder plane A portion become large. In addition, in such a configuration, the perpendicularity between the hole of the holder 3 and the plane A part, and the threaded part of the holder 3 and the taper guide 5
The mechanical precision with the taper part needs to be processed with extremely high precision, resulting in high costs.

The present invention has been made in view of the above problems, and
The purpose of this is to reduce surface runout and eccentricity of the disk fixed to the shaft of the spindle motor.
This is to reduce surface runout of the shaft 2 and eccentricity of the shaft 2.

<Means for Solving the Problems> In order to solve the above problems, the present invention provides a method for fixing a holder having an adapter inserted into a motor shaft, comprising: forming the holder and the adapter as separate parts; When fixing, first insert the elastic member into the shaft, then apply an adhesive with a relatively long curing time between the holder and the shaft, insert it, and then use the first metal fitting before the adhesive hardens. to adjust the surface runout of the holder and maintain the adjusted state, and after the shaft and holder are completely fixed with adhesive, the first metal fitting is removed, and a curing time is set between the adapter and the shaft. A relatively long adhesive is applied and inserted, and before the adhesive is fixed, the eccentricity of the adapter is adjusted using a second metal fitting, and the adjusted state is maintained, so that the adapter and the shaft are bonded with adhesive. After it was completely fixed, the second metal fitting was removed.

It is characterized by this.

<Embodiment> FIG. 1 is a sectional view showing an embodiment of the holder fixing method according to the present invention. In the figure, the same elements as in FIG. 3 are given the same reference numerals, and redundant explanations will be omitted. In this invention, an elastic collar 13 is first inserted into the shaft, and this collar 1
A disk-shaped holder 14 is inserted on top of 3. The inner diameter of this holder 14 is machined to be slightly larger than the outer diameter of the shaft 2, and an adhesive 19 having a relatively long curing time is applied to the inner diameter side of the holder 14. Reference numeral 15 denotes a first metal fitting having a convex cross-section and a disk shape with a hole in the center, and the center hole is inserted into the shaft 2. Small diameter portion 15a of this first metal fitting 15
A relief 15b is provided inside the holder 15b and contacts the holder 14 in a ring shape. Numeral 17 is a set screw provided from the outer diameter portion of the first metal fitting 15 toward the shaft, and the first metal fitting 15 is fixed to the shaft by this set screw 17. Adjustment screws 16 are provided vertically from the upper surface of the first metal fitting 15 toward the holder, and are arranged at three locations on the outside of the ring-shaped small diameter portion, dividing the first metal fitting 15 into three equal parts. . 1
Reference numeral 8 denotes a displacement meter provided on the outer peripheral surface A of the holder 14.

In the above configuration, the spindle motor 1 is rotated at a low speed, the surface runout of the upper surface A of the holder 14 is measured by the displacement meter 18, and the three adjustment screws provided on the first metal fitting 15 are used to adjust the holder according to the measurement results. Press down and adjust so that the surface runout is zero. In this case, since an elastic collar is inserted into the lower surface of the holder 14, adjustment is easily possible.
Note that the adjustment of the surface runout of the holder is performed before the adhesive applied to the gap between the holder and the shaft hardens.

According to the above method, it is possible to reduce the surface runout of the holder to zero.

FIG. 2 shows the holder 14 held by the first metal fitting 15.
FIG. 4 is a cross-sectional view showing a method for adjusting eccentricity of the shaft after the adhesive is cured after the surface runout of the shaft is adjusted to zero. In the figure, the same elements as in FIG. 1 are given the same reference numerals and redundant explanations are omitted, but 20 is a cylindrical adapter having a step C. The inner diameter of this adapter 20 is machined to be slightly larger than the outer diameter of the shaft 2, and an adhesive 19 having a relatively long curing time is applied to the inner diameter side of the adapter 20. 21 is a second metal fitting. This second metal fitting 21 has a U-shaped cross section, and is arranged so as to cover the holder 14 with the adapter 20 passing through the center thereof. It is fixed by pressing. A pressure spring 23 is fixed to the upper part of the second metal fitting 21 by two screws 24, and the tip of the pressure spring 23 contacts a stepped portion C provided on the adapter 20 to press the adapter against the upper surface of the holder. These pressing springs are provided at two or more locations on the upper surface of the holder to press the adapter against the upper surface of the holder 14 in a well-balanced manner. Reference numeral 22 denotes adjustment screws which are screwed into screw holes provided in at least three places on the upper surface of the second metal fitting to press the adapter 20. 26 is adapter 2
Detect the eccentricity of the adapter by rotating the shaft at low speed with a displacement meter installed near the outer circumference of the shaft, adjust according to the eccentricity while pressing with the adjustment screw 22, and hold for a certain period of time when the eccentricity becomes zero. and allow the adhesive to harden.

According to the above method, a spindle motor without shaft eccentricity can be obtained.

The holder with no runout and the adapter with no eccentricity are fixed to the shaft by the first metal fitting 15 and the second metal fitting 21, and the disk is mounted using the taper guide 5 and nut 6 shown in the conventional example in Fig. 3. Fix it.

Note that the fixed object fixed on the holder is not limited to the disk, but can be applied to various disks that require precise fixation.

<Effects of the Invention> As specifically explained above in conjunction with the embodiments, according to the present invention, while measuring the surface runout and eccentricity of the holder inserted into the shaft, it is possible to adjust and assemble the holder so that the eccentricity is minimized. Therefore, it is possible to easily realize a spindle motor having a holder with extremely small surface runout and eccentricity of the guide portion. Furthermore, since the holder itself does not require mechanical precision, the manufacturing cost of the holder can be reduced.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views showing one embodiment of the present invention, and FIG. 3 is a cross-sectional view showing an example of a conventional method. 1... Spindle motor, 2... Motor shaft, 13... Collar, 14... Holder, 15...
First metal fitting, 16, 22...adjustment screw, 17, 2
5... Set screw, 18, 26... Displacement meter, 19...
...Adhesive, 20...Adapter, 21...Second metal fitting, 23...Press it.

Claims (1)

[Scope of Claims] 1. A method for fixing a holder having an adapter inserted into a motor shaft, wherein the holder and the adapter are formed as separate parts, and the holder is inserted into and fixed to the shaft and has a circumference centered on the shaft. a first metal fitting having adjustment screws arranged equally in at least three locations;
a second metal fitting that is inserted into and fixed to the outer peripheral surface of the holder and has a pressing spring that presses the adapter against the holder and an adjustment screw that presses the outer periphery of at least three equal parts of the adapter; and a second metal fitting that has a predetermined thickness. and a displacement meter, and when fixing the holder, there are two steps: inserting the collar into the shaft, inserting the holder into the shaft, and filling the gap between them with a relatively long curing time. The step of applying an adhesive, before the adhesive is fixed, insert the first metal fitting into the shaft and fix it, and use the displacement meter to measure the holder while alternately pressing the surface of the holder with the adjustment screw. the step of adjusting surface runout, leaving the holder in the state after the surface runout adjustment until the adhesive is completely fixed;
removing the first metal fitting after fixation, inserting the adapter and the second metal fitting into the shaft, applying an adhesive with a relatively long curing time between the adapter and the shaft, and fixing the adapter to the holder; a step of pressing the adapter against the holder using a pressing spring, and adjusting the eccentricity of the adapter using the displacement meter while pressing the outer periphery of the adapter with the adjustment screw of the second metal fitting before the adhesive is fixed; A method for fixing a spindle motor holder, the method comprising the steps of: removing the second metal fitting after the adapter and shaft are completely fixed with an adhesive.