JPS5979408A - Fixed magnetic disk device - Google Patents

Abstract

PURPOSE:To reduce greatly the error test formating (ETF) time and to perform a large quantity of ETF work with a small number of ETF devices by securing simultaneous execution of the ETF work with plural magnetic heads. CONSTITUTION:For the ETF work, a connection card 28 of an ETF41 is inserted to a connector 26 to connect an ETF28 with a sealed-up part HDA3. The ETF41 has the same number of read/write circuits R/W42 as the number of ICs of a subject HDA, i.e., the number of magnetic head groups. Therefore a simultaneous analog or digital check is possible with all magnetic head groups (a magnetic head among magnetic head groups) by giving a necessary command from the mein body 45 of ETF to the HDA3 through the card 28. Furthermore a switching circuit is set into the card 28 or a circuit selecting part 20 in order to invalidate all functions of the part 20 when the card 28 is inserted to the connector 26.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fixed magnetic disk device in which a magnetic disk and a magnetic head are housed in a sealed case. It has a configuration in which a plurality of 8-ki takes formed by coating, plating, sputtering, etc. are stacked and rotated, and the takes are written or read by a magnetic head that can reciprocate in the direction of the center of the magnetic disk. Therefore, magnetic disk drives are widely used as storage devices with large capacity and short access time (selective operation time for writing or reading) are available at relatively low cost, and their recording density also depends on the magnetic properties of the magnetic disk. Advances in film surface formation technology and magnetic head manufacturing technology have led to a growing trend toward higher densities.

When using such a magnetic disk device.

Detection of all defects on the magnetic disk in advance (generally, it is not economical to eliminate all defects from the formation process of the magnetic film surface 5 of the magnetic disk, so defects below a certain number are allowed) In order to record without defective areas, it is necessary to predetermine the recording area on the magnetic disk (usually referred to as total error test formatting, abbreviated as ETF).

Methods for detecting defects on magnetic disks Conventionally, recording is performed using a specific pattern mainly consisting of sinusoidal waveforms, and the modulation (disturbance of the waveform caused by waviness) and missing pits (waveform caused by scratches) that appear on the output are detected. defects) and extra bits (unerased portions of VC after erasing records)
The so-called analog test method is used to test all parts (irregular outputs that appear due to irregular output), but as recording density has increased in recent years, the area of one recording unit on a magnetic disk has become very small. Ah! Now, it is no longer possible to ignore minute defects on the film surface that were not considered a problem, so in addition to the analog inspection method described above, specific data patterns (signal combinations that are likely to cause errors in recording overlays) are now being used.
A digital inspection method, in which the output is recorded while shifting it multiple times and detects errors in the output, has also come to be used in combination.

On the other hand, as the recording density and capacity of the magnetic disk drive increases, a so-called fixed disk type structure in which a magnetic disk and a magnetic head are housed in a sealed case is used. ! :f) However, as shown in Fig. 1, such a conventional fixed magnetic disk device has a nubindle in which a plurality of magnetic disks 4 are stacked, and two adjacent magnetic disks. A positioning device (hereinafter referred to as a carriage) 10 that supports a plurality of magnetic head supports 12 on which four magnetic heads 6 are mounted, and an integrated circuit 14 that is mounted one per magnetic head support.
(This integrated circuit includes a magnetic head selection circuit that selects any one of two to four magnetic heads, and an amplifier circuit that performs initial stage amplification of the output from the selected magnetic head.) A selection circuit 20 for selecting any one of them is sealed from the substrate 18 and the cover 16VC (hereinafter this sealed portion' (r-HDA)) 1
The selection circuit 20 is configured to be connected to the outside via a connector 22.

Therefore, in order to perform ETF operations on the magnetic disk drive configured as described above, as shown in FIG. Remove 32 and connect formatting device (abbreviated as ETF) 40 VW42w, carriage? :It is necessary to position one cylinder, perform the analog test and digital test described above on all magnetic heads sequentially, and then execute this on all cylinders.

Therefore, it takes a very long time to perform the E'l'F operation on conventional fixed magnetic disk devices, so it is expensive to perform all the E'l'F operations on a large number of magnetic disk devices.
There is a drawback that a large number of iETF devices must be prepared.

The purpose of the present invention is to eliminate the above-mentioned drawbacks, reduce the total ETF time by enabling E 'l' F work to be performed simultaneously on a plurality of magnetic heads, and
A large number of magnetic disk devices q) E T by TF device
VC aims to provide an economical fixed magnetic disk device that can perform all F operations.

A fixed-foot magnetic disk device according to the present invention includes a plurality of magnetic disks, a plurality of magnetic heads that perform read/write operations on and from the magnetic disks, and a plurality of adjacent magnetic heads among the magnetic heads. A magnetic head selection circuit is provided for one magnetic head group and selects any one magnetic head from the magnetic head group, and an amplifier circuit performs initial stage amplification of the output of the selected magnetic head. a plurality of integrated circuits, and any one of the plurality of integrated circuits.
a circuit selection section having a selection circuit for selecting the magnetic head; the magnetic disk, the magnetic helad, the integrated circuit, and the circuit selection section are housed in a sealed case, and The fixed magnetic disk device connects an operating write/read circuit and the circuit selection section through a first connector attached to the sealed case.

A second connector is attached to the sealed case and connects the plurality of integrated circuits without going through the selection circuit.

The present invention will be explained in detail below with reference to the drawings.

Referring to FIG. 3, which illustrates one embodiment of the present invention.

A plurality of magnetic rings 4 are stacked at equal intervals and rotated by being attached to a spindle 8, and - several magnetic heads 6 are mounted on a spindle 8.
A set of 2 to 4 μ pieces (Usually, one magnetic head corresponds to the facing surfaces of two magnetic rings, and when two magnetic heads are used corresponding to one side of the magnetic ring, 4 pieces.

When one is used, two are often used as a set.)
One magnetic head support 121C is supported and mounted on the carriage 10 to perform reciprocating motion for positioning operation.

One integrated circuit 14 is mounted on the magnetic head support 12, and VC in this integrated circuit is a magnetic head selection circuit for selecting any one magnetic head from a group of magnetic heads. and an amplifier circuit for performing initial stage amplification of the output from the magnetic head.

Connect all of the above-mentioned integrated circuits to the circuit selection section 20,
A selection circuit is provided for selecting only one of these integrated circuits to operate based on a signal sent through the connector 24.

Further, the integrated circuit 14 is directly connected to the connector 26 without going through the one-circuit selection section 20.

It consists of a spindle 8 (including the magnetic ring 4), a machined carriage 10 (including the magnetic head 6 and the integrated circuit 14), a circuit selection section 20μ, a cover 16 and a substrate 18 to prevent dust from entering from the outside. It is housed in a sealed case! 71 Connectors 24 and 26 are attached to the sealed case to electrically connect the inside and outside of the sealed case.

As shown in FIG. 4, when performing the E']'F operation on a fixed magnetic disk drive that is MFy as described above, the connection card 28 of the connector 261CE'l''F41 is connected as shown in FIG.
Insert and connect ETF28 and HI) A3.

ETF 41 is the target) (Since it is equipped with the same number of rW42'e as the number of integrated circuits of D A, that is, the number of magnetic head groups, through the connection card 28 from the main body 45 of the ETF) Analog or digital testing can be performed simultaneously on all magnetic head groups (one magnetic head in each magnetic head group) IC by giving the necessary commands. Therefore, by repeating the above operation for one HDA as many times as the number of magnetic heads included in one set of magnetic heads, the ETF operation for all magnetic heads can be executed, so the total processing time can be reduced. Minutes can be shortened to minus 0
Note that when the connection card 28 is inserted into the connector 26, 1
A switching circuit is incorporated in the connection card 28 or in the circuit selection section 20 so that all operations of the circuit selection section 20 are disabled Vr-.

As explained above in detail, by using the fixed magnetic disk device of the present invention, the time required for ETF work can be significantly reduced, making it possible to economically perform ETF work for a large number of magnetic disk devices with a small number of ETF devices. Not only does it have the effect of providing a fixed magnetic ring device, but it also makes it possible to distinguish between groups of magnetic heads, so when a failure occurs in a magnetic head, it becomes easier to search for the failed magnetic head. There are also side effects.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an example of a conventional fixed magnetic disk device, FIG. 2 is a block diagram of an example in which a formatting device is fully connected to the example of the fixed magnetic disk device of FIG. 1, and FIG.
The figure is a sectional view of one embodiment of the present invention, and FIG. 4 is a block diagram of an example in which a formatting device is connected to the embodiment of FIG. 3. In fig. 2.3... HDA, 4... Magnetic ring, 6...
Magnetic head, 8... Spindle, 10... Positioning device (carriage λ12... Magnetic head support, 14...
...Integrated circuit, 16...Cover,]8...Substrate, 2
0...Circuit blocking unit, 22, 24.26...Connector, 28...Connection card, 32...Writing/reading circuit ("W), 40°41...Formatting device ( ETF C 42...Writing/reading circuit ('W),
44. 45...Formatting device main body (
ETF itself). No./Concave u No. 2 Fig. 36- Fig. 3, Fig. 24

Claims (1)

[Claims] Provided for a magnetic head group including a plurality of magnetic disks, a plurality of magnetic heads that write to and read from the magnetic disk, and a plurality of adjacent magnetic heads among the magnetic heads. a plurality of integrated circuits including a magnetic head selection circuit that selects any one magnetic head from the magnetic head group and an amplifier circuit that performs initial stage amplification of the output of the selected fc magnetic head; a circuit selection section having a selection circuit for selecting any one of the integrated circuits, the magnetic disk, the magnetic head, the integrated circuit, and the circuit selection section are housed in a sealed case. , a fixed magnetic disk device that connects a write/read circuit that performs write/read operations of the magnetic head and the circuit selection section by a first connector attached to the sealed case, A fixed magnetic disk device comprising a second connector that connects all of the plurality of integrated circuits without going through the selection circuit.