JPS6128293Y2 - - Google Patents

Description

[Detailed Description of the Invention] In the present invention, a servo head and a read/write head are each supported by a carriage by a head arm, the carriage is coupled to a drive source by an actuator, the drive source moves the carriage, and the servo head is provided with a servo head. The present invention relates to an improvement in an access mechanism in a magnetic recording device, such as a magnetic disk drive, in which information positions a read/write head in a predetermined position.

Generally, in access mechanisms such as those described above, the servo head is located near the center of a number of read/write heads and is generally not aligned with the center of the actuator.

Therefore, when this access mechanism is actuated, even if the servo head is located at the center of the carriage group, a resonance point exists between the head and the actuator because the actuator is not aligned with said center. For this reason, electrical compensation has conventionally been performed in the servo circuit by removing this resonance component.

However, such a compensation method has the disadvantage that the number of circuit components increases and its design is complicated.

Therefore, an object of the present invention is to eliminate the above-mentioned drawbacks and to provide an access mechanism that does not require a compensation means for eliminating resonance components in the servo circuit. To achieve this, the servo head and the read/write head are each supported on a carriage by a head arm,
An access mechanism for a magnetic recording device in which the carriage is coupled to a drive source by an actuator,
It is characterized in that the servo head is supported on the carriage so as to be substantially on the extension of the central axis of the actuator in the moving direction. The present invention will be explained below using the drawings.

FIG. 1 is a diagram showing a conventional access mechanism, FIG. 2 is a diagram showing a conventional servo circuit, FIG. 3 is a diagram showing one embodiment of the access mechanism of the present invention, and FIG. 4 is a diagram of the access mechanism of the present invention. FIG. 2 is a diagram showing a servo circuit in FIG. In the figure, numerals 1 and 1' are recording media such as magnetic disks, and in particular 1' is a servo medium. 2 is a read/write head, 2' is a servo head, 3 is a head arm, 4 is a carriage, 5 is an actuator, 6 is a driving means such as a linear motor, and 7 is a base. As shown in FIG. 1, in a conventional access mechanism, a servo head 2' is generally located approximately in the middle of two groups of read/write heads. This is done by setting the center of the head group as the servo head to reduce the positioning error of each head.

On the other hand, the actuator 5 that connects the carriage 4 to the motor 6 is usually placed close to the base 7, although it depends on the mounting position of the motor, so the servo head 2' and the actuator 5 are generally not aligned.

Therefore, when the carriage 4 is driven, a resonance point exists between the servo head 2' and the actuator 5, and the servo head 2' resonates.

This will affect the servo circuit as shown in FIG.

In FIG. 2, 2' is a servo head, and servo information from the servo head 2 is amplified by an amplifier 21 and demodulated by a demodulation circuit 22 to generate a position signal, which is then fed to a motor drive circuit 2.
5, a servo signal is generated in the control circuit 24 for the motor drive circuit, and feedback controlled.

Since the position signal extracted from the servo head 2 contains a resonance component as described above, conventionally, a filter 23 having predetermined characteristics is inserted to remove the resonance component.

However, this method has disadvantages in that the design of the filter 23 is complicated and the number of circuit components increases. FIG. 3 is a diagram showing an embodiment of the access mechanism of the present invention. In the figure, the same parts as in FIG. 1 are given the same symbols.

The difference in FIG. 3 from FIG. 1 is that the servo head 2' and the actuator 5 of the carriage 4 are aligned in center. In other words, servo head 2' is at the center of the head group (center of carriage 4).
The longitudinal center of the actuator is approximately aligned with the center of the actuator.

In this way, the servo head 2' and the actuator 5' become nearly rigid bodies, and the resonance of the servo head 2' can be ignored.

FIG. 4 is a diagram showing a servo circuit when the access mechanism of the present invention is used, and the structure and operation are similar to those in FIG. 2, so the explanation will be omitted, but compared to FIG. It is excluded.

As described above, according to the present invention, by supporting the servo head 2' and the actuator 5 on the carriage so that their centers substantially coincide with each other, the influence of resonance of the servo head on the servo circuit can be eliminated, which is extremely practical.

In addition, in the case of a small magnetic disk device with 2 to 4 disks, the servo head is installed at the bottom of the disk, so it is easy to align it with the actuator, and there is no need to align the position of the servo head with the drive means. It can be carried out effectively without having to do so.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional access mechanism, FIG. 2 is a diagram showing a conventional servo circuit, FIG. 3 is a diagram showing one embodiment of the access mechanism of the present invention, and FIG. 4 is a diagram of the access mechanism of the present invention. FIG. 2 is a diagram showing a servo circuit in FIG. In the figure, numerals 1 and 1' are recording media such as magnetic disks, and in particular 1' is a servo medium. 2 is a read/write head, 2' is a servo head, 3 is a head arm, 4 is a carriage, 5 is an actuator, 6 is a driving means such as a linear motor, and 7 is a base.

Claims (1)

[Scope of utility model registration request] In an access mechanism for a magnetic recording device in which a servo head and a read/write head are each supported by a carriage by a head arm, and the carriage is coupled to a drive source by an actuator, the servo head is positioned approximately on a line extending in the moving direction of the central axis of the actuator. An access mechanism for a magnetic recording device, characterized in that the access mechanism is supported on the carriage.