JPS6120717Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic disk storage device such as a hard disk, and more particularly to an improvement in a device for detecting head collision between the magnetic disk and a flying head. In general, a magnetic disk storage device has one or more magnetic disks arranged at predetermined intervals, rotates the magnetic disks, and uses an air flow generated by the rotation of the magnetic disks to move the disks onto the magnetic disks. A magnetic head for writing/reading information is floated to write/read information.

In such a magnetic disk storage device, since the distance between the magnetic disk and the floating magnetic head is several micrometers, it is highly susceptible to dust.

In other words, if dust enters between the magnetic disc and the floating magnetic head, the floating magnetic head will physically contact and slide the magnetic disc through the dust, causing scratches on the magnetic disc. . In addition, the dust may deteriorate the flying posture of the floating magnetic head, causing the floating magnetic head to come into direct contact with the magnetic disk, which may not only scratch the magnetic disk but also damage the floating magnetic head. It was hot. (These are called head crashes.) Scratches or damage to these magnetic disks or floating magnetic heads not only make it impossible to write/read information, but also cause the information recorded on the magnetic disks to disappear. It was an important issue.

Conventionally, the following methods have been adopted to take these measures.

(b) The magnetic disk is housed in a sealed cover called a shikorawad, and the inside of the case is always kept clean.

(b) In order to detect the head crash, an AE (Acousse Emission) element is provided on the support bar of the floating magnetic head, and the vibration generated when the magnetic disk comes into contact with the floating magnetic head is detected. is set back from above the magnetic disk.

However, even if both of these methods are used, head crushing still occurs, and it can only be detected after head crushing has been performed for a considerable period of time, and the detection methods are not sufficient. Therefore, the object of the present invention is to at least detect head crashes quickly, accurately and reliably, so that head crashes can be stopped as quickly as possible. ,
In a magnetic disk storage device in which information is recorded by placing a floating magnetic head mounted on a carriage between each of the magnetic disks, light emitted from a light emitting element is placed between each of the magnetic disks. a pair of light-emitting elements and a light-receiving element arranged so that the light enters the light-receiving element after passing between This is achieved by providing a carriage control circuit which causes the floating magnetic head to retreat from above the magnetic disk when a head crash is detected.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

The figure shows an embodiment of the magnetic disk storage device of the present invention.

In the figure, 1 is a magnetic disk, 2 is a carriage,
3 is an arm, 4 is a carriage drive unit, 5 is a carriage control unit, 6 is a light source, 7 is a light receiver, 8 is a head crush detection circuit, 9 is a control unit, 10
indicates the display section, respectively.

The magnetic disk storage device is composed of a magnetic disk 1, a carriage 2, an arm 3, a carriage drive section 4, a carriage control section 5, and a control section 9. Further, the arm 3 has a floating magnetic head (not shown). is provided.

The magnetic disk 1 is rotated at high speed, and a floating magnetic head (not shown) is placed on the magnetic disk 1 by a carriage 2 via an arm 3 to write/read information on the magnetic disk 1. In such a magnetic disk storage device, in the present invention, the light source 6
and a light receiver 7 are arranged so that light passes between the magnetic discs 1 as shown in the figure.

These magnetic disk 1, floating magnetic head, etc. are called a sealed shroud. It is housed in a case, and the air inside the case is in a clean state.

Normally, there are no obstacles between the light source 6 and the photoreceiver 7, and the amount of light received by the photoreceiver 7 reaches its maximum value. However, if a head crash occurs for some reason, the recording medium on the magnetic disk 1 may peel off. Since the amount of light passing between the magnetic disks 1 changes due to dust and fragments of the magnetic head, a head crash can be detected by utilizing the change in the amount of light received by the light receiver 7.

Therefore, in the present invention, the signal from the light receiver 7 is sent to the head crush detection device 8, and the device 8 monitors changes in the signal from the light receiver, and if a decrease in the amount of light arriving at the light receiver 8 is detected. If so, the lamp corresponding to the light receiver 8 is turned on by the display 10, and the controller unit 9 is notified of this,
Furthermore, this signal drives the carriage drive unit 4 via the carriage control 5, and the carriage 2 is moved so that the floating magnetic head is retracted from above the magnetic disk 1.
It is designed to operate. Incidentally, the display 10 is provided on an operator panel of the apparatus or the like.
Further, the controller section 9 is provided in the device or in a controller provided in another device.

In this way, in the present invention, the occurrence of head crushing can be quickly detected by detecting the amount of dust in the air between the magnetic disks 1 by the attenuation of light passing through the head crushing between each magnetic disk. Since the head is evacuated, these operations can be carried out before the damage spreads to areas other than the magnetic disk where the head crash occurred, so the head crash can be kept to a minimum.

[Brief explanation of the drawing]

The figure shows an embodiment of the magnetic disk storage device of the present invention. In the figure, 1 is a magnetic disk, 2 is a carriage, and 3 is a magnetic disk.
1 is an arm, 4 is a carriage drive section, 5 is a carriage control section, 6 is a light source, 7 is a light receiver, 8 is a head crush detection circuit, 9 is a control section, and 10 is a display section.

Claims (1)

[Claims for Utility Model Registration] A magnetic disk storage device that has a plurality of magnetic disks and records information by placing a floating magnetic head mounted on a carriage between each of the magnetic disks, comprising: A pair of light emitting element and light receiving element arranged between the magnetic disks so that the light emitted from the light emitting element passes between the respective magnetic disks and then enters the light receiving element; A head crush detection device that detects a head crush based on a change in the amount of light generated by the head, and a carriage control circuit that retreats the floating magnetic head from above the magnetic disk when the head crush is detected by the head crush detection device. Magnetic disk storage device.