JPS61192081A - Head supporting device - Google Patents

Abstract

PURPOSE:To shorten a supporting frame length by providing a hole portion at a center of a head supporting from elastic spring part. CONSTITUTION:A rotary spring constant Kp around a longitudinal axis 10 is figured out by a sum of tortional and bending springs and even though such a width b of the elastic spring part 4 is small, a small tortional spring constant causesa large bending spring constant as long as the width b h of its hole portion 17 is large; its small extent may produces proportionally larger Kp. Even though the hole portion 17 with the large width b h is provided at the elastic spring part 4 and the small width b of elastic spring part 4 renders a vertical spring constant Kz smaller, the rotary spring around the second axis 11 enables its constant Kp to be a traditional value. And the larger the fixed part width b+bh of such a supporting frame 2, the larger a stiffness beam part 5 width will be, while a tortional stiffness around the longitudinal axis 11 of this portion becomes lower, mounting of an expansion part 18 of a flexible frame 12 by lapping under the stiffness beam part 5 renders its stiffness higher.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the miniaturization of a head support device for a magnetic disk drive.

[Conventional technology]

3 and 4 are a plan view and a side view, respectively, showing a conventional head support device disclosed in Japanese Patent Publication No. 51)-22827, in which (1) is a rigid arm portion, and (2) is a support body. ,
(3) is a screw for attaching the support (2) to the rigid arm part (1), and (4) is the support (2) adjacent to the rigid arm hip (1).
2) is the elastic spring part, and (5) is the rigid beam part of the support (2).

It extends from the elastic spring part (4) to a free end, at which it produces a load movement. (6) is the rigid beam part (5
) is a flange to increase the rigidity, and (7) is a support (2
), (8) is a magnetic disk, and (9) is a magnetic spatula P.

GG is the longitudinal axis of the support (21), aυ is the second axis perpendicular to the longitudinal axis a1, and α2 is the flexible support (held at the free end (7) of 21 to which the magnetic head (9) is attached). body.

03 is a welding part that joins the flexible body α2 and the support r2+, α
4 is the outer flexible finger of the flexible body (l), αS is the central tongue of the flexible body α2 to which the magnetic head (9) is attached, ae is the free end (7) of the support (2); provided with a central tongue (1
61, the magnetic head (9) K is a load protrusion that transmits the load force, and the contact portion is a spherical trap.

Next, the operation will be explained. The rigid arm part (1) is connected to the magnetic head (9) by the magnetic head positioning mechanism (not shown) K.
) on the magnetic disk (8) as a signal track (not shown)
K position.

The support body (2) applies an initial deflection to the elastic spring part (4), and transmits the force generated when returning this deflection to zero through the rigid beam part (5), especially to the load protrusion. Magnetic head +91) - is pressed against the magnetic disk (8). In this case, in order to keep the pressing force almost constant and to make it easier for the magnetic head (9) to follow the vertical movement of the magnetic disk surface, the support (2) has a small spring constant KMk in the vertical direction at the loading protrusion aS. I need to do it one day at a time. Here, the spring constant 2 can be approximately found by equation (1).

tg KZ 2E --(1) 12J5　ρ(2−ρ) Here, ρ=lo/l.

b is the width of the elastic spring part (4).

t is the thickness of the elastic spring portion (4).

j is the length of the support (2).

jO is the length of the elastic spring part (4).

E is the longitudinal elastic modulus of the support (2).

In the conventional type shown in FIGS. 3 and 4, the support (2
) The length l of the elastic spring part (4) is made thinner so that the thickness t of the elastic spring part (4) is made smaller.

On the other hand, the flexible body (I2 is an elongated outer flexible finger portion α4
This allows the head (9) to rotate with a small force around the longitudinal axis (I) of the support (2) and around the second axis αυ around the loading protrusion α9. Because of this K, the magnetic head (9) can easily follow the curvature of the magnetic disk surface.However, the magnetic head (9)
When the support body (2) undergoes these movements, the position of the load protrusion a9 moves and the magnetic head (9)
The force may cause your position to shift or your posture to become unstable. Therefore, in order to increase the spring constant of the support body (2) against these rotational forces, the width of the nine elastic spring parts (4) is made sufficiently larger than the free end part (7), etc. This is due to the deformation of the elastic spring portion (4) of the support body +21. The rotational spring constant Kp around the longitudinal axis QG is approximately determined by equation (2).

Here, G is the transverse elastic modulus of the support (2).

Note that the rotational spring constant of the support (2) about the second axis aυ is generally sufficiently larger than Kp.

[Problem that the invention seeks to solve]

For example, in a magnetic disk device using a small-diameter magnetic disk such as 8 inches, two or more magnetic heads are arranged on one surface of the magnetic disk, and these are mounted on the same rigid arm in order to shorten the positioning time of the magnetic head. In this case, from the viewpoint of space, the length of the head support device must be shortened by about half. However, the vertical spring constant KZ of the conventional head support device
is 5 as in the above formula [1], so as the length l becomes shorter, KZ increases in inverse proportion to I5.

In order to counter this and to reduce Kz, it is necessary to increase the length jo of the elastic spring portion (4), reduce the width 2, and reduce the thickness t.

However, if this is done, the rotational spring constant Kp of the support part (2) about the longitudinal axis αQ becomes small, as can be seen from the above equation (2), and the support part (2) becomes unusable as a head support device.

Furthermore, when the thickness t of the support body (2) is reduced, the rigidity of the rigid beam portion (5) decreases and the nine-turn spring constant Kpt is further reduced.

Conventional head support devices have the above-mentioned problems and cannot be used in small-diameter magnetic disk drives in which two or more magnetic heads are arranged on one surface of a magnetic disk.

This invention was made to solve the above problems, and is about half the length of the conventional head support device.
The object of the present invention is to provide a head support device in which the spring constant KZ in the vertical direction is equal to or smaller than that of the conventional device, but the rotational spring constant Kp about the longitudinal axis is as large as that of the conventional device.

[Means for solving problems]

The head support device according to the present invention has a hole in the center of two elastic spring parts.

[Effect]

In the present invention, the hole in the center of the elastic spring part reduces the spring constant Kp due to vertical bending deformation of the elastic spring part, and increases the rotational spring constant Kp about the longitudinal axis due to torsional deformation.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
2 and 2 are a plan view and a side view, respectively, showing a head support device according to an embodiment of the present invention, and in FIG. 2, α
η is the hole provided with the elastic spring part (4) K, am is the flexible body 0
This is an extension part in which a part of z is thickly combed and attached to the rigid beam part (5) by spot welding, for example. Others are the same as or equivalent to conventional ones.

Next, the operation will be explained. The basic operations of the rigid arm part (1) and the support body (2+) are the same as those of the conventional one.

Spring constant K in the vertical direction of the head support device according to the present invention
z is determined by the above formula (1). The rotational spring constant Kp around the longitudinal axis αQ can be approximately determined by the following equation.

Here, 5 = bVb, b h ; width of the hole αη.

As can be seen from equation (3), the two-rotation spring constant Kp is determined by the sum of the first term, the torsional spring constant, and the second term, the bending spring constant, and even if the width of the two-elastic spring part (4) is small, If the width bh of the hole aη is large, 3 (=bh/b) becomes larger, and the bending spring constant (second term) is increased by the amount that the torsional spring constant (first term) is smaller, and Kp can be made larger. Therefore, as shown in Fig. 1, a six-part fin with a large elastic spring part + 41 K @ 1)h is provided at 5, and the width bt of the elastic spring part (4) - 9 is made smaller to make the spring constant in the vertical direction smaller. Also, the rotational spring constant Kp around the second axis αυ can now be kept at the same value as before.

Also, as the width b -4-bh of the fixed part of the support body (2) increases, the width of the rigid beam part (5) increases, and the torsional rigidity around the longitudinal axis aaD of this part increases. However, in response to this, it is possible to increase the rigidity of the flexible body H by overlapping the extension part side of the flexible body H under the rigid beam part (5) at 5 as shown in Fig. 1. did it.

In addition, in the above embodiment, the flexible body (12 extensions QlIt-
Although it is attached under the rigid beam part (5) in a plate shape, it is possible to make an uneven part on this extended part a9, or to make a flexible member (a member different from Iz) in a plate shape, or The rigid beam portions (5) K may be attached in a stacked manner.

Furthermore, the same effect can be obtained by partially changing the thickness of the support body (2) and making only the rigid beam part (5) thicker.

In addition, in the above embodiment, the load protrusion t1e is
Although the description has been made with respect to the one provided at the free end of the bending body (1a), the same effect can be obtained with the one provided on the bending body (1a side).

〔Effect of the invention〕

As described above, according to the present invention, since the hole is provided in the center of the elastic spring part of the head support, the spring constant in the vertical direction can be made small and the rotational spring constant about the longitudinal axis can be made large. The length of the support can be shortened without changing the directional spring constant and the rotational spring constant about the longitudinal axis.

[Brief explanation of drawings]

1 and 2 are a plan view and a side view, respectively, showing a head support device according to an embodiment of the present invention, and FIGS. 3 and 4 are a plan view and a side view, respectively, showing a conventional head support device. be. (1) is a rigid arm part, [2] is a support body, (4) is an elastic spring part, (5) is a rigid beam part, (7) is a free end, (9
) is the magnetic head, circle is the flexible body, αe is the load protrusion, (
2. The same reference numerals in the figures indicate the same or equivalent parts.

Claims (3)

[Claims] (1) from a rigid arm part, an elastic spring part provided on the rigid arm part and adjacent to the rigid arm part, and a rigid beam part extending from the elastic spring part to a free end and providing a loading force at the free end; a support body, a flexible body held at the free end of the support body and to which the magnetic head is attached, and a loading protrusion provided on the support body or the flexible body and transmitting the load force to the magnetic head. What is claimed is: 1. A head support device comprising: a hole portion in the center of said elastic spring portion; (2) The head support device according to claim 1, wherein the flexible body is attached to overlap the rigid beam portion. (3) The head support device according to claim 1 or 2, wherein a member having a convex portion is stacked on the rigid beam portion.