JP2636820B2 - Head carriage device for magnetic disk drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a head carriage device for a magnetic disk drive.

[0002]

2. Description of the Related Art In a conventional head carriage device of a magnetic disk drive, a head carriage assembly is movably provided on a guide rail on a chassis, and a motor for moving the head carriage assembly is fixed to a chassis of the magnetic disk drive. Is generally used. This is the same whether the motor is a step motor or a linear motor.

[0003]

As described above, in the head carriage device, since the head carriage assembly and the motor are separate bodies, it is necessary to separately position and attach the head carriage assembly to the chassis, and assembly adjustment is required. There is a problem that it is troublesome and is not suitable for increasing the precision of the access of the magnetic head.

[0004] In addition, there is a demand for downsizing of the head carriage device, but there is a problem that it is difficult to downsize the head carriage device with the conventional structure. SUMMARY OF THE INVENTION It is an object of the present invention to provide a head carriage device for a magnetic disk device that solves the above-mentioned problems.

[0005]

FIG. 1 is a diagram showing the principle configuration of a head carriage device 1 according to the present invention. In the drawing, reference numeral 2 denotes a surface type linear motor, in which a plate-shaped movable element 4 is provided above the stator assembly 3 and the movable element 4 moves in the directions of arrows X ₁ and X ₂ . Regarding the principle configuration of the surface type linear motor, see US Pat. No. 3,376,578 (198).
6). The mover 4 is formed by integrating a core plate and a head carriage base.

A head carriage assembly 5 has a head carriage base and a head arm 6 fixed thereto. Reference numeral 7 denotes a lower magnetic head, which is attached to the upper surface of the head carriage base. An upper magnetic head 8 is attached to the head arm 6.

[0007]

FIG. 2 is an exploded perspective view of a head carriage device according to the present invention, FIG. 3 is a sectional view taken along line III--III in FIG. 2 showing the structure of a linear motor, and FIG. FIG. 2 is an exploded view of the linear motor of FIG. In each figure, the same reference numerals are given to portions corresponding to the components shown in FIG.

First, the structure of the linear motor 2 will be described. The linear motor 2 includes a stator assembly 3 and a mover 4. The stator assembly 3 will be described. A pair of stator magnetic poles 11 and 12 are fitted and fixed to a rectangular permanent magnet frame 10 and arranged side by side. Stator coils 13 and 14 are wound around the magnetic poles 11 and 12, respectively.

Reference numerals 15 and 16 denote divided support members.
The frame 10 is supported. The support member 15 is combined with the frame 10 by fitting the notch 15a to the protruding piece 10a of the frame 10, and is screwed to the lower surface of the frame 10 by screws 17,18. The other support member 16 is combined with the frame body 10 by fitting the notch 16a to the protruding piece 10b of the frame body 10, and is fixedly bonded to the support member 15. The side plate 16 b of the support member 16 protrudes above the frame 10.

Reference numeral 19 denotes a receiving plate, which is sandwiched between the frame 10 and the side plate 15b of the support member 15. Reference numeral 20 denotes a bottom cover made of an electrically insulating synthetic resin, which is engaged with the supporting members 15 and 16 by using claws 21 and covers the bottom side of each of the above members.

To describe the movable element 4, reference numeral 30 denotes a rectangular plate, for example, SUS-304 or SUS-304.
-404 or other stainless steel. This plate 30
A core plate 31 made of a ferromagnetic plate is fixed to the lower surface of the substrate. The core plate 31 includes the stator magnetic poles 1.
The two core piece rows 32,
33 are formed. The core piece rows 32 and 33 have a configuration in which core pieces 34 and 35 are arranged at an equal pitch p as shown in FIG. The core pieces 34 of the core piece row 32 and the core pieces 35 of the core piece row 33 are different from each other by p / 2. The core piece rows 32 and 33 are formed by punching the slit group 36 with a press and remaining.

The movable element 4 has support frames 37 on both sides thereof.
It is supported by 38 so as to be movable in the directions of arrows X ₁ and X ₂ , and is provided above the stator assembly 10. Support frame 3
Numerals 7 and 38 are made of synthetic resin having a low coefficient of friction and have an L-shaped cross section.
7a to 37d and 38a to 38d are formed.

The support frame 37 is mounted on the left side of the stator assembly 10 in a state where the rollers 40 to 43 are fitted to the roller fitting portions 37a to 37d, respectively. Another support frame 38
Are mounted on the right side of the stator assembly 10 in a state where the rollers 44 to 47 are respectively fitted to the roller fitting portions.

Each roller partially protrudes from the roller fitting portion. Rollers 40, 41, 44, and 45 abut on the right and left upper surfaces of the frame 10, and rollers 42 and 43 abut on the inner surface of the receiving plate 19. The rollers 46 and 47 are in contact with the inner surface of the side plate portion 16b. Each roller is made of stainless steel.

The mover 4 is attracted to the frame 10 with a force F ₁ by the magnetic force of the permanent magnet frame 10 and is integrated with the stator assembly 3. Next, the head carriage assembly 5 will be described. The head carriage assembly 5 has the mover 4 as a carriage base.

The lower magnetic head 7 is fixed on a support plate 50 attached to the plate 30. Reference numeral 51 denotes a support block, which is fixed to an end of the plate 30. The head arm 6 is supported by a supporting plate spring 52 at its base by a pressing plate 53 and is supported by screws 54 and 55 to a supporting block 51.
It is fixed on the top.

The support block 51 and the head arm 6 are made of SUS-304 or SUS-40 similarly to the plate 30.
4 products. As described above, the head carriage device 1 has a configuration in which the linear motor 2 and the head carriage assembly 5 are integrated, and is considerably smaller than the conventional one.

FIGS. 2 and 3 show a state in which the head carriage device 1 is mounted on the chassis of the magnetic disk device. 6
Reference numeral 0 denotes a chassis of the magnetic disk drive. 61 and 62 are positioning reference projections, which are formed on the chassis 60.

Reference numeral 63 denotes a leaf spring, which is bent between the pins 64 and 65 on the chassis 60 and bridged. The head carriage device 1 is set by inserting the linear motor 2 between the projections 61 and 62 and the leaf spring 63, and the leaf spring 63 is elastically deformed from its original state, so that the receiving plate 19 is substantially elongated in the longitudinal direction. It is in contact with the projections 61 and 62 near both ends of the side plate portion 16b opposite to the receiving plate 19 and in contact with the outside of the center. The linear motor 2 has a spring force F of the leaf spring 63.
₂ and pressed against the projections 61 and 62, and the X ₁ ,
The position is determined in the Y ₁ and Y ₂ directions orthogonal to the X ₂ direction.

In this state, the linear motor 2 (stator assembly 3) is appropriately moved in the directions of arrows X ₁ and X ₂ to adjust the position with respect to the reference position of the disk spindle or the like. To the chassis 6 with screws 66 and 67
Screw to zero. As described above, the attachment of the head carriage device 1 to the chassis 60 is simple.

The head carriage assembly 5 supports the mover 4.
The head carriage assembly 5
No position adjustment is required and the head carriage assembly 5
No guide rail is required. Also, the head carriage
Even when the device 1 is attached to the chassis 60,
19 is pushed by the leaf spring 63 and the arrow Y₁Slightly bent in the direction
And the plate 30 and the supporting frames 37 and 38 are
19 and the side plate portion 16b.
Plate 30 (movable part 4, head carriage assembly)
5) Arrow Y ₁, Y_TwoThe play in the direction is zero.

Next, the movement of the head carriage assembly 5 during recording and reproduction of the magnetic disk device will be described. The head carriage assembly 5 is driven by the linear motor 2, moves in the arrow X _1, X ₂ direction with the mover 4 moves in the arrow X _1, X ₂ direction. The driving principle of the linear motor 2 is described in the aforementioned U.S. Patent Publication and "Linear Motors and Applied Technologies" (published by Jikkyo Shuppan Co., Ltd., author: Kazuto Yamada), pp. 119-121. Is omitted.

The characteristics of the linear motor 2 will be described. The mover 4 moves as the plurality of rollers 40 to 47 roll. Therefore, the movable element 4 by the magnetic force acts downward force F _1, and also the weight of the head carriage assembly 5 is applied, the movement load of the movable element 4 is small.

[0024] By the F _1, the movable element 4 is an arrow Z _1, Z
It moves with its position in _two directions regulated. Further, the force F
Due to ₂ , the mover 4 moves with its position also regulated in the directions of the arrows X ₁ and X ₂ .

The driving force for moving the mover 4 acts on the two right and left core piece rows 32 and 33. Core piece 3
4 and 35 are different from each other by の of the pitch p. As described above, the mover 4 is stably transferred in the directions of the arrows X ₁ and X ₂ without rattling in the directions of the arrows Y ₁ , Y ₂ , Z ₁ and Z ₂ .
Positioning is performed accurately.

Therefore, the head carriage assembly 5 integral with the mover 4 is also stably transported in the directions of the arrows X ₁ and X ₂ and positioned with high accuracy, and the access of the magnetic heads 7 and 8 is more accurate than that of the conventional one. Well done. Next, the effect of heat will be described.

When the temperature in the magnetic disk device changes,
Each component of the head carriage assembly may undergo thermal expansion and contraction, and the relative positions of the upper and lower magnetic heads may be unnecessarily changed. However, in this embodiment, the plate 30,
Since both the support block 51 and the head arm 6 are made of the same material, the relative positional accuracy between the magnetic heads 7 and 8 can be maintained well even when the temperature changes.

The plate 30, the support block 51,
The head arms 6 do not necessarily have to be made of the same material, as long as they have substantially equal thermal expansion coefficients.

[0029]

As described above, according to the present invention,
Since the head carriage base has a structure integrated with the core plate, the access accuracy of the magnetic head is the same as the positional accuracy of the core plate of the linear motor, so that the access accuracy of the magnetic head can be improved. Further, since the head carriage base and the head arm are made of the same material or made of a material having substantially the same thermal expansion coefficient, even when the temperature in the magnetic disk device changes, the upper magnetic head and the lower magnetic head are changed. Can be kept from changing.

[Brief description of the drawings]

FIG. 1 is a principle configuration diagram of the present invention.

FIG. 2 is an exploded perspective view of one embodiment of the present invention.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is an exploded perspective view of a linear motor portion in FIG.

FIG. 5 is an enlarged view of a core plate in FIG. 4;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Head-carriage apparatus 2 Surface linear motor 3 Stator assembly 4 Mover (carriage base) 5 Head carriage assembly 6 Head arm 7 Lower magnetic head 8 Upper magnetic head 10 Permanent magnet frame 11, 12 Stator magnetic pole 13 , 14 Stator coil 15, 16 Support member 15b, 16b Side plate 19 Receiving plate 20 Bottom cover 30 Plate 31 Core plate 32, 33 Core piece row 34, 35 Core piece 36 Slit group 37, 38 Support frame 37a-37d, 38a- 38d Roller fitting portion 40 to 47 Roller 50 Support plate 51 Support block 60 Chassis 61, 62 Positioning reference projection 63 Plate spring 64, 65 pin

 ────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-233476 (JP, A) JP-A-59-217271 (JP, A) JP-A-63-37872 (JP, A)

Claims (1)

(57) [Claims] 1. A a plate lower magnetic head Ru placed
Core piece column ing to integrate the core plate is formed, the slidable f head carriage base coupled with the head carriage base and one end portion, a head arm upper magnetic head is arranged If has a fixed coil, and more becomes a stator assembly for driving the head carriage base magnetically, the stator assembly, and the above f head carriage base of the core plate to constitute a linear motor A head carriage device for a magnetic disk drive, wherein the plate of the head carriage base and the head arm are made of the same material or materials having substantially equal thermal expansion coefficients.