JPS62162278A - Spindle motor holding mechanism - Google Patents

Abstract

PURPOSE:To improve rigidity as a complete sheel type frame, to reduce the size and to obtain a structure prevented from the generation of temperature stress by fixing one bearing pressed into a spindle by a stator block and bushes fixed on a frame, engaging the outer wheel of the other bearing with the buses fixed on the frame and applying prepressure in the thrust direction. CONSTITUTION:The bushes 25, 26 are inserted into the united shell type frame 21 and the bearings 23, 24 pressed into the upper and lower parts of a shaft 22 are inserted into the bushes 25, 26. A stator 13 of a motor is held by the stator block 27, which is fixed on the bush 25 with a screw 33. A rotor 18 of the motor is held by a housing 28 and fixed on a shaft 22. The outer wheel 24a of the bearing 24 is provided with a spring 29 for applying prepressure in the thrust direction. To form a sealed structure, the periphery of a lead wire 30 of the motor is sealed with a packing 32 formed between a printed circuit board 31 and the stator block 27.

Description

[Detailed Description of the Invention] [Summary] Regarding the spindle structure of a magnetic disk drive, in a double-sided spindle with a built-in motor, the stator is held by a stator block in order to house the motor, and fixed to the stator block and frame. With the bush that was made,
One bearing press-fitted into the spindle is fixed, and the outer ring of the other bearing is fitted with a gap in the bushing 7 fixed to the frame, creating a structure in which preload is applied in the thrust direction, and rigidity is achieved as a complete shell type frame. It is designed to be taller and more compact, and has a structure that does not cause temperature stress.

[Industrial application field]

The present invention relates to a spindle structure for a magnetic disk drive, and more particularly to a double-sided spindle motor holding structure that includes a built-in motor.

The spindle structure of a magnetic disk device is a double-sided spindle in order to increase the rigidity of the spindle. In the case of a double-sided spindle, the motor that rotates the spindle is generally provided outside the device, which increases the mounting space. Furthermore, since the motor is located on the outside, it is not possible to form a complete shell-type frame, and therefore a highly rigid frame cannot be obtained. Therefore, there is a need for a double-sided spindle that incorporates a motor to improve mounting density and uses a shell-type frame to increase the rigidity of the frame and realize downsizing.

[Prior Art] Conventional spindle motor holding structures include the following.

FIG. 3 is a diagram illustrating a conventional spindle motor holding structure. As shown in FIG. 3, the magnetic disk drive 1 includes a spindle 5 having a motor 4, a preload bearing 6 at the top and a fixed bearing 7 at the bottom, in an interior sealed by a frame 2 and a cover 3. 7 is held on the frame 2, a preload bearing 6 is held on the cover 3 through bushes 8, and a plurality of discs 9 are attached to the spindle 4. Reading/writing of information on the disc 9 is performed by a magnetic head attached to a carriage (not shown), but the gap between the magnetic head and the disc 9 is extremely narrow due to magnetic characteristics, and the magnetic head,
It has a sealed structure so as not to damage the disc 9.

Section 4 shows another conventional spindle motor holding structure, in which both ends of the central shaft 1) are fixed to an integral shell frame 10 with screws 12, and the stator 1 of the motor is mounted on the central shaft 1).
3 is provided, the rotor 18 is fixed to the housing 17, and a disc is attached to the housing 17. A preload bearing (preload in the thrust direction by a spring 14 on the inner ring of the bearing) 15 on the lower side of the center shaft 1), a fixed bearing 16 on the upper side
is fixed to the housing 17.

In addition, 19 is the ground contact (
A plastic carbon contact) makes contact with the earth spring 20 connected to the frame IO to earth the rotating body.

[Problem that the invention seeks to solve]

The conventional spindle motor holding structure shown in FIG. 3 requires a large mounting space because the motor is provided outside the device. The fork frame 2 and the cover 3 are connected with screws to form an integral frame, and since a complete shell-type frame cannot be formed, there is a problem that the rigidity is low.

The central axis ll of the conventional spindle motor holding structure shown in Fig. 4
is iron-based, the frame 10 is aluminum-based, and the central axis 1)
is tightened to the frame 10 by the screws 12, so that temperature stress is generated in the frame 10. It has a structure in which the central shaft is fixed and the outside rotates, and bearings 15.16
The outer ring of the bearing rotates, and bearing loss is large due to the viscosity of the grease. Furthermore, since the position where the ground contact 19 contacts the housing 17 is far away from the center shaft and the sliding speed is fast, in order to remove the ground (19, 20) of the rotating body, the lead wire must be pulled out through the inside of the center shaft 1). However, there were problems such as difficulty in drawing out the lead wires.

[Means for solving problems]

FIG. 1 is a diagram explaining the present invention in detail.

In the figure, 21 is a one-piece shell type frame, and the frame 21 has holes into which bushings 25 and 26 are inserted. 22 is a shaft, and bearings 23 are press-fitted at the top and bottom.
．． 24, the bearings 23.24 being inserted into the bushings 25.26. The stator 13 of the motor is held in a stator block 27.
is fixed to the bushing 25. The rotor 18 of the motor is fixed to a housing 28, which is fixed to the shaft 22. Further, the outer ring 23a of the bearing 23 at the upper part of the shaft 22 is adhesively fixed to the stator block 27 and positioned by a bush 25. The lower bearing 24 is preloaded by the frame 21 stroke.

Further, in order to obtain a sealed structure, the periphery of the motor lead wire 30 is sealed with a packing 32 provided between the printed circuit board 31 and the stator block 27. Furthermore, while pulling out the lead wire 30 through the hole 37 provided in the bushing 25,
The outer periphery of the joint surface of the stator block fixing screw 33, the stator pro 27 outside the lead wire pull-out portion, and the bushing 25 is sealed with a packing 34. Note that 35 is a ground contact, and 36 is a ground contact spring.

[Effect]

That is, by holding the stator 13 of the motor in the stator block 27 and fixing the stake block 27 to the bush 25 and the fixed bearing 23, the motor can be built in, and since the motor is not externally attached, mounting space can be saved.

The rotor 18 of the forked motor is fixed to the housing 28, and the housing 28 is further fixed to the shaft 22, so that the housing 28 is rotated by the shaft 22. Therefore, since the inner rings of the bearings 23 and 24 rotate, there is less loss due to grease than when the outer rings rotate. The grounding of the fork rotor can be done from the center of the shaft 22, making it easy to ground.

The stator 13 of the fork motor is held by a stake block 27 and fixed to a bush 25.
5 through the lead wire 30, it can be easily pulled out.

Since the frame 21 is completely shell-shaped, the rigidity of the frame 21 is strong, and furthermore, the outer rings 23a and 24a of the bearings 23 and 24 are positioned on the frame 21 via the bushes 25 and 26, and a preload in the thrust direction is applied to the outer ring 24a. Because of the structure, shaft 22 (iron type),
No temperature stress occurs on the frame (aluminum).

〔Example〕

FIG. 2 is a diagram explaining the present invention in detail.

Note that common symbols throughout the figures indicate the same objects.

FIG. 2 is a sectional view showing the spindle motor holding structure. In the figure, a bushing 2 is attached to an integral shell frame 21.
5.26 has a hole into which it is inserted. Bearings 23.24 press-fitted into the upper and lower parts of the shaft 22 are bushes 25.2.
6 and the bushings 25, 26 are screwed to the frame 21. The stator 13 of the motor is held by a stator block 27, which is fixed to the bush 25 with screws 33 and also to the outer ring 23a of the bearing 23 by adhesive. The motor rotor 18 is held in a housing 28 that is fixed to the shaft 22. Further, the outer ring 23a of the bearing 23 at the upper part of the shaft 22 is fixed to a bushing 25, and the lower bearing 24 is fixed to the bushing 23 fixed to the frame 21.
6, and further the outer ring 24 of the bearing 24
A spring 29 is provided to apply a preload to a in the thrust direction.

Further, in order to obtain a sealed structure, the periphery of the motor lead wire 30 is sealed with a packing 32 provided between the printed circuit board 31 and the stator block 27. Furthermore, a hole 37 is made in the bushing 25, and the lead wire 30 is passed through the bushing 25 and pulled out. Furthermore, the screw 33 that fixes the stake block
The outer periphery of the joint surfaces of the stator block 27 and the bushing 25 outside the lead wire extraction portion is sealed with a packing 34. Note that 35 is a ground contact, and 36 is a ground contact spring.

By holding the stator 13 of the motor in the stator block 27, the motor can be built in, and the motor is not attached externally as in the past, saving mounting space.

Since the side-held spindle structure with a built-in morph is held in the integral shell frame 21, high rigidity can be obtained.

Since the inner rings of the fork bearings 23 and 24 rotate, losses due to the viscosity of the grease are small. Since the rotating body is fixed to the shaft 22, the rotating body can be grounded from the shaft 22, making it easy to ground the rotating body.

The gaskets 32 and 34 seal the gap between the screws 33 that fix the stator block 27 and the gap between the joint surfaces of the stake block 27 and the bush 25, thereby providing a sealed magnetic disk device.

Since the housing 28 is rotated by the fork shaft 22, and the inner rings of the bearings 23 and 24 are rotated, there is less loss due to grease than when the outer ring rotates, and the ground of the fork rotating body can be grounded from the center of the shaft 22. Easy to ground.

Since the lead wire 30 is passed through the diagnostic bush 25 holding the stator block 27, it can be easily pulled out.

The outer ring 23a of the bearing 23 is fixed, and the bearing 24
Since a preload is applied to the outer ring 24a in the thrust direction,
(Unlike the conventional method of fixing both sides of the shaft to the frame) no temperature stress occurs on the shaft 22 (iron-based) and the frame (aluminum-based).

〔Effect of the invention〕

As explained above, according to the present invention, in the double-sided spindle structure of a magnetic disk, by fixing it to the stator roller push of the motor, it is possible to incorporate the motor and reduce the size.Furthermore, by incorporating the motor, The complete shell-shaped frame provides high rigidity, and the rotating shaft structure reduces loss due to bearing grease.

[Brief explanation of drawings]

Figure 1 is a diagram explaining the present invention in detail. Figure 2 is a diagram explaining the invention in detail. Figure 3 is a diagram explaining a conventional spindle motor holding structure. Figure 4 is another conventional spindle. It is a figure explaining a motor holding structure. In the figure, 13 is a stator, 18 is a rotor, 21 is a frame, 22 is a shaft, 23, 24 is a bearing, 25, 26 is a bush, 27 is a stator block, 28 is a housing, 29 is a spring, 30 is a lead wire, 31 is the printed circuit board, 32.34 is the gasket, 33 is the screw, 35 is the ground contact, 36 is the ground contact spring,

Claims (2)

[Claims] (1) Bearings (23, 24) press-fitted into both ends of the shaft (22) are fixed to the integral shell frame (21) via bushes (25, 26), and the center of the shaft (22) is This is a spindle motor holding structure of a dual-end type, which is equipped with a motor on both sides, and the outer ring 23a of one of the bearings (23) is positioned by the bush (25), and the stator (13) and rotational position detection element of the motor are positioned by the bush (25). The outer ring 24a of the other bearing (24) is fixed to the stator block (27) holding the printed circuit board (31) mounted with the frame (21).
) A spindle motor holding structure characterized by comprising a spring (29) positioned on the bush (26) attached to the outer ring 24a and applying a preload in the thrust direction to the outer ring 24a. (2) The area around the lead wire (30) of the motor is sealed with a packing (32) provided between the printed circuit board (31) and the stator block (27).
) through the hole (37) provided in the bush (25) and pull out the screw (33) that fixes the stator block (27), and the bush (25) of the stator block (27) in the lead wire pull-out section. 2. The spindle motor holding structure according to claim 1, wherein the outer periphery of the joint surface of the spindle motor is sealed with a packing (34).