JPH0533672U - Head access motor - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to a head access motor, and it is an object of the present invention to simplify manufacturing and to eliminate variations in performance. [Structure] A carriage 4 rotatable around a rotary shaft 1, having a magnetic head 2 at one end and a coil 3 at the other end,
An outer yoke 6a and an inner yoke 6b that hold the permanent magnets 5 at positions sandwiching the rotation locus of the coil 3 from both sides, and a pair of side yokes installed between the ends of the outer yoke 6a and the inner yoke 6b. 6
a magnetic circuit member 6 composed of c and 6d, and at least two adjacent yokes in the magnetic circuit member 6,
It is formed by integrally forming a sintered material.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a head access motor for a magnetic disk device. In recent years, magnetic disk devices have been remarkably improved in storage density, and accordingly, high-accuracy positioning and high speed are required. For this reason, a voice coil motor has been widely used as a head access motor for recent magnetic disk devices.

[0002]

[Prior Art]

 A magnetic circuit member of a conventional head access motor is shown in FIGS. The magnetic circuit member 6 includes an outer yoke 6a and an inner yoke 6b provided along the rotation locus of the coil 3, and a pair of side yokes 6c for connecting the outer yoke 6a and the inner yoke 6b. , 6d are joined together, and the permanent magnet 5 is adhered to the inner yoke 6b and the outer yoke 6a.

[0003]

[Problems to be solved by the device]

 However, in the above-mentioned conventional example, since the four yoke parts 6a, 6b, 6c, and 6d are manufactured and joined together to form the magnetic circuit member 6, the permanent magnet that most affects the performance. Since there is a large variation in the size of the void between the five, there is a large variation in the magnetic flux density, which makes it difficult to maintain the quality of the motor, and the number of parts is large, so the number of assembly steps is large. It had the drawback of

The present invention has been made to solve the above-mentioned drawbacks, and an object of the present invention is to provide a head access motor which is easy to manufacture and has no variation in performance.

[0005]

[Means for Solving the Problems]

 According to the present invention, the above-mentioned object is, as shown in FIG. 1 corresponding to the embodiment, a carriage 4 which is rotatable around a rotary shaft 1 and has a magnetic head 2 at one end and a coil 3 at the other end, An outer yoke 6a and an inner yoke 6b that hold the permanent magnets 5 at positions sandwiching the turning locus of the coil 3 from both sides, and a pair of side yokes installed between the ends of the outer yoke 6a and the inner yoke 6b. And a magnetic circuit member 6 composed of 6c and 6d, wherein at least two adjacent yokes in the magnetic circuit member 6 are provided by providing a head access motor integrally formed of a sintered material. R.

[0006]

[Action]

 In the present invention, the magnetic circuit member 6 is formed by sintering at least two adjacent yokes by sintering. Since the two adjacent yokes are integrally formed, the number of parts is reduced, the number of manufacturing steps is reduced, and the side yokes 6c or 6d are always included in the two adjacent yokes. Therefore, the distance between the outer yoke 6a and the inner yoke 6b is accurately maintained, and the characteristics are made uniform.

[0007]

【Example】

 Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, FIG. 1 shows an overall view of a head access motor. The head access motor has a carriage 4 and a magnetic circuit member 6, and the carriage 4 is rotatably held by a rotary shaft 1 at a substantially central portion.

The carriage 4 has a pivot (not shown) with respect to the rotary shaft 1, and has an arm 8 for holding the magnetic head 2 via a gimbal 7 at one end, and an arm 8 at the end opposite to the magnetic head 2. It has a coil 3 to be mounted, and a driving current is passed through the coil 3 to obtain a turning force.

The magnetic circuit member 6 has an outer yoke 6a formed of a high magnetic material, an inner yoke 6b, and a pair of side yokes 6c and 6d. The outer yoke 6a has an inner wall and an outer wall of the inner yoke 6b. The permanent magnets 5 are fixed to each other, and the coil 3 is inserted into the space formed by the permanent magnets 5 arranged so as to face each other.

The assembled state of the magnetic circuit member 6 is shown in FIG. In this embodiment, the inner yoke 6b and one of the side yokes 6d are previously integrated by firing a sintered material, and the other side yoke 6c is adhered to the sintered member. The permanent magnet 5 is bonded to the outer wall of 6b.

On the other hand, the outer yoke 6a is formed by a conventional method, and after the permanent magnet 5 is adhered to the inner wall surface of the outer yoke 6a, the outer yoke 6a is adhered to the end portions of the side yokes 6c and 6d. As a result, the space formed by the permanent magnets 5 and 5 bonded to the outer yoke 6a and the inner yoke 6b is maintained at a predetermined size.

In the above description, the case where the one side yoke 6d and the inner yoke 6b are integrally molded is shown, but in addition to this, as shown in FIG. The side yokes 6c and 6d can be integrally molded, or all the yokes can be integrally formed.

[0013]

[Effect of the device]

 As is apparent from the above description, the head access motor according to the present invention can reduce the number of parts, improve the dimensional accuracy of the magnetic flux generating portion, and obtain an efficient magnetic circuit.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a magnetic circuit member.

FIG. 3 is a view showing another embodiment of the present invention.

FIG. 4 is a diagram showing a conventional example.

5 is a diagram showing an assembled state of FIG. 4. FIG.

[Explanation of symbols]

 1 rotating shaft 2 magnetic head 3 coil 4 carriage 5 permanent magnet 6 magnetic circuit member 6a outer yoke 6b inner yoke 6c, 6d side yoke

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yuichi Yoshida, 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa, Fujitsu Sinter Limited

Claims (1)

[Scope of utility model registration request] 1. A carriage (4) rotatable about a rotary shaft (1), having a magnetic head (2) at one end and a coil (3) at the other end, and rotation of the coil (3). The outer yoke (6a) and the inner yoke (6b), which hold the permanent magnets (5) at positions sandwiching the locus from both sides, and the outer yoke (6a) and the inner yoke (6b) are installed between the ends. A magnetic circuit member (6) including a pair of side yokes (6c, 6d), and at least two adjacent yokes in the magnetic circuit member (6) are integrally formed of a sintered material. Access motor.