JPH10222822A - Rotary magnetic recording/reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a maintenance-free rotary magnetic recording/reproducing device without deteriorating performance and reliability due to head clogging. SOLUTION: This device is provided with a reproducing head 2, a cleaning roller 3 removing depositions on a head gap, a detection means for detecting the level of the output signal of the reproducing head 2 and a comparator 4 comparing the level of the output signal detected by the detection means with a beforehand set setting value and outputting a signal when the level of the output signal is the setting value or below, and head cleaning is performed by the cleaning roller 3 based on the output signal from the comparator 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary magnetic recording / reproducing apparatus used for backing up data of a computer.

[0002]

2. Description of the Related Art In recent years, in a rotary magnetic recording / reproducing apparatus, an automatic head cleaning function has been proposed in order to satisfy a high reliability and maintenance-free market demand.
For example, in an apparatus used for data backup of a computer, it is necessary to automatically clean magnetic powder adhering to a head gap in order to realize a maintenance-free requirement.

[0003]

The head cleaning method of the conventional rotary magnetic recording / reproducing apparatus is a method of cleaning the head when a recording signal cannot be reproduced. In this method, it is difficult to detect clogging of the head unless it deteriorates until reproduction becomes impossible, and there has been a problem that clogging of the head causes inconveniences such as a reduction in signal level and a deterioration in error rate.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a maintenance-free rotary magnetic recording / reproducing apparatus free from performance deterioration and reliability deterioration due to head clogging.

[0005]

According to a first aspect of the present invention, there is provided a rotary magnetic recording / reproducing apparatus, comprising: a reproducing head; a removing means for removing a deposit in a head gap; and a detecting means for detecting a level of an output signal of the reproducing head. A comparator that compares the level of the output signal detected by the detecting means with a preset value and outputs a signal when the level of the output signal is equal to or less than the set value, based on the output signal of the comparator. The head is cleaned by the removing means.

According to the rotary magnetic recording / reproducing apparatus of the first aspect, when the output signal level of the reproducing head is equal to or lower than the set value, the head is cleaned by the removing means.
Cleaning of the head can be performed automatically without waiting until the recording signal cannot be reproduced. According to a second aspect of the present invention, there is provided a rotary magnetic recording / reproducing apparatus according to the first aspect, wherein the number of times the level of the output signal per track of the reproducing head becomes equal to or less than a preset value is measured based on the output signal of the comparator. The head cleaning operation by the removing means is stopped when the number of times measured by the counter is plural.

According to the rotary magnetic recording / reproducing apparatus of the second aspect, in addition to the function of the first aspect, when the number of times that the level of the output signal of the reproducing head per track becomes equal to or less than the set value is plural times, That is, when the output signal returns to a state where a good output signal can be obtained even temporarily during one track, it is not determined that the head is clogged, and the head cleaning operation by the removing means is stopped. Wear of the head and the cleaning roller can be prevented. In this way, the head cleaning can be properly performed only when it is determined that the head clogging has occurred by distinguishing between the dropout causing the tape side and the head clogging.

[0008]

Embodiment

First Embodiment A first embodiment of the present invention will be described with reference to FIG. In FIG. 1, 1 is a rotary cylinder, 2
Is a reproducing head, 3 is a cleaning roller (removing means) for removing magnetic powder attached to the head gap,
Reference numeral 4 denotes a comparator for comparing the level of the output signal of the head 2 detected by the detecting means (not shown) with a preset value. The comparator 4 may compare the analog signal of the head 2 with the set value, or may compare the digital signal with the set value via a detection unit such as an A / D converter.

First, the level of the output signal of the head 2 is measured by the detecting means. When the level of the output signal from the head 2 is smaller than the set value by the comparator 4, a signal for performing head cleaning is output, and the cleaning roller 3 is driven to clean the head 2. According to the rotary magnetic recording / reproducing apparatus configured as described above, when the level of the output signal of the reproducing head 2 is equal to or less than the set value due to the adhesion of the magnetic powder or the like, the cleaning roller 3
, The head 2 can be automatically cleaned without waiting until the recording signal cannot be reproduced. Therefore, it is possible to obtain a maintenance-free rotary magnetic recording / reproducing apparatus without causing inconveniences such as a decrease in signal level and a deterioration in error rate due to head clogging.

Second Embodiment A second embodiment of the present invention will be described with reference to FIG. In FIG. 2, 1 is a rotary cylinder, 2
Is a reproducing head, 3 is a cleaning roller (removing means) for removing magnetic powder attached to the head gap,
Reference numeral 5 denotes A / for detecting the level of the output signal of the head 2.
A D converter (detection means), 6 is an arithmetic unit which also serves as a comparator for calculating the output of the A / D converter 5, and 7 is an arithmetic unit 6
Is a counter that counts the output of.

First, the output signal level of the head 2 is set to A /
The measured value is measured by the D converter 5, and the measured value is compared with a set value set in advance by the calculator 6. The rotary cylinder 1 is provided with a reference signal generator (not shown) for detecting the start and end of one track. The counter 7 counts the number of times and time when the level of the output signal is lower than the set value.

The count value of the number of level reduction sections per track by the counter 7 is determined by the arithmetic unit 6, and if the count value is a plurality of times per track, that is, a good level even temporarily during one track. When the output signal returns to the state where the output signal is obtained, it is determined that the head is not clogged, and it is determined that the dropout has a cause on the tape side, and the cleaning operation is not performed.

If the time of one level reduction section by the counter 7 is equal to or longer than a predetermined time (for example, 2/3 of the reproduction time of one track), the cleaning operation is performed regardless of the number of times. According to the rotary magnetic recording / reproducing apparatus configured as described above, head clogging is determined based on the number and time when the level of the output signal of the reproducing head 2 per track becomes equal to or less than the set value, and the cleaning roller 3 Since the head cleaning is performed, cleaning of the head 2 can be automatically performed without waiting until the recording signal cannot be reproduced. In addition, normal head reading can be performed properly only when it is determined that head clogging has occurred by distinguishing a normal signal reading error, that is, dropout and head clogging, and the head can be cleaned by unnecessary head cleaning. The wear of the cleaning roller 2 and the cleaning roller 3 is not accelerated. Therefore, it is possible to obtain a maintenance-free rotary magnetic recording / reproducing apparatus without causing inconveniences such as a decrease in signal level and a deterioration in error rate due to head clogging.

It should be noted that the counter 7 may count only the number of level-lowering sections per track, and may not perform the cleaning operation if it is performed a plurality of times per track.

[0015]

According to the rotary magnetic recording / reproducing apparatus of the first aspect, when the level of the output signal of the reproducing head is equal to or less than the set value, the head is cleaned by the removing means. Without cleaning the head. Therefore,
A maintenance-free rotary magnetic recording / reproducing apparatus can be obtained without causing inconveniences such as lowering of signal level and deterioration of error rate due to clogging of magnetic powder or the like into a head gap.

According to the rotary magnetic recording / reproducing apparatus of the second aspect, in addition to the effect of the first aspect, when the number of times that the level of the output signal of the reproducing head per track becomes equal to or less than the set value is plural, That is, when the output signal returns to a state where a good output signal can be obtained even temporarily during one track, it is not determined that the head is clogged, and the head cleaning operation by the removing means is stopped. Wear of the head and the cleaning roller can be prevented. In this manner, the head cleaning can be performed properly only when it is determined that the head clogging has occurred by distinguishing the dropout and the head clogging caused on the tape side. Therefore, a maintenance-free rotary magnetic recording / reproducing apparatus can be obtained without causing inconveniences such as a decrease in signal level and a deterioration in error rate due to clogging of the magnetic powder or the like into the head gap.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a rotary magnetic recording / reproducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a rotary magnetic recording / reproducing apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 rotary cylinder 2 head 3 cleaning roller (removal means) 4 comparator (comparator) 5 A / D converter (detection means) 6 arithmetic unit 7 counter

Claims (2)

[Claims] 1. A reproducing head, a removing means for removing deposits in a head gap, a detecting means for detecting a level of an output signal of the reproducing head, and setting a level of an output signal detected by the detecting means in advance. A comparator that compares the set value and outputs a signal when the level of the output signal is equal to or less than the set value, and performs head cleaning by the removing unit based on the output signal of the comparator. Magnetic recording and reproducing device. 2. A counter for measuring the number of times that the level of an output signal per track of a reproducing head becomes equal to or less than a preset value based on an output signal of a comparator, wherein the counter measures the number of times. 2. The rotary magnetic recording / reproducing apparatus according to claim 1, wherein the head cleaning operation by the removing unit is stopped when the number of times is plural.