JPS6057583A - Rotary type magnetic recorder and reproducing device - Google Patents

Abstract

PURPOSE:To always accurately move a head to a specified track even when the temperature circumstance varies, by measuring the temperature with a temperature detector fitted to a recording and reproducing device and correcting the head position by calculating the error in the head position due to thermal expansion. CONSTITUTION:A temperature detector 203 detects temperature of a disk 201 and the temperature information is converted into a voltage signal 205 by a converter 204. A reference voltage generating circuit 206 generates a reference voltage signal 207 whose value is equal to that of the voltage signal 205 at a reference temperature T. Both voltage signals 205 and 207 are subjected to subtraction at a subtracting circuit 208 and a new voltage signal 209 of (205,207) is outputted. The voltage signal 209 is amplified at an amplifier circuit 210 and a head positional error correcting signal 211 is outputted to a head shifting mechanism driving circuit 213. The circuit 213 drives a head shifting mechanism 214 so that a head 202 moves by a shifting quantity specified by a track specifying signal 212 to which a correcting quantity by the head positional error correcting signal 211 is added. In such a way, the head is shifted always accurately even when the temperature circumstance varies.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary magnetic recording/reproducing device.

As the recording density of rotary magnetic recording and reproducing devices increases, the track density also increases, and high accuracy is required for positioning the magnetic head in the trunk. The temperature of the magnetic disk changes due to changes in the environment in which the device is used, and the distance between tracks is not always constant due to crystallinity expansion. In conventional rotating magnetic recording devices, head position errors due to 71i11 degree expansion are not corrected, and head position errors occur when the temperature changes, resulting in the recorded information not being able to be reproduced correctly. The present invention has the disadvantage that the temperature may be lost, and the humidity range in which the device can be used is also limited. The purpose is to always perform recording and reproduction correctly. The drawings will be explained in detail below.

FIG. 1 shows the displacement of the head position due to thermal expansion, and shows a state in which the head 101 is loaded into the n-th trunk 102. 107 is trunk width, 110 is? The (1-1)th track is located closer to the outer circumference of the disk than the first track 102. At the current reference temperature T
The position of the rack was between solid lines 106 and 104, but due to an increase of △1゛ 7# and 1i degrees from T, the disk expands due to humidity and shifts by 1 minute to 108 on the outer circumferential side, The position of the n track is between broken lines 107 and 108. In this way, the head position error 1'ΔI becomes 4= due to the humidity change of /\T. According to the present invention, the head position is 1 by the error △X? t is corrected and the head is moved to the correct position 109.

FIG. 2 shows an embodiment in which the above-described hennode position error is corrected according to the present invention. By the track designation signal of 212, 21
The head moving mechanism drive circuit 3 drives the head moving mechanism 214 to move the magnetic head 202 fixed to the carriage 215 to the designated trunk of the disk 2 (11).Meanwhile, the temperature detector 203 detects the temperature of the disk 201. is detected and the information is converted into a voltage signal 2 by a converter 204.
Can be converted to 05. Reference numeral 206 denotes a reference voltage generation circuit which generates a reference voltage signal 207 having the same value as the voltage signal 205 at the quaternary crystallinity T. 205°207
1) The L pressure signal is subtracted by the subtraction circuit 208,
A voltage signal 209 of 205 minus 207 is output.

Addition 1'+J circuit 21o Te1irt'f15 Pressure-F
j209 is increased by 1'r;

The head moving mechanism drive circuit moves the head moving mechanism 214 by one step so that the head moves by the amount of head movement based on the trunk designation signal 212 plus the correction amount based on the head position error correction signal 211. let Note that when the humidity of the disc is at the reference temperature T, only the track designation signal 212 is input to the head moving mechanism drive circuit 21, so in this state, the head moving mechanism 214 is activated so that the belly button moves to the correct position. drive.

As described above, according to the present invention, the head position difference due to temperature expansion is corrected, so that even if the temperature environment changes, the head can always be accurately moved to the specified rack. Also, since the humidity expansion coefficient is constant between []°C and about 100°C, there is an advantage that the operating temperature range can be wider than the conventional operating temperature range of 5°C to 50°G. 0The embodiment discussed here is merely one embodiment.

Brief Description of UAilii FIG. 1 is a diagram showing the deviation of the head from the track due to temperature change, and FIG. 2 is a block diagram showing one embodiment of the present invention.

101・-Magnetic head 1o2・・n track 107・
Track width 108...Track deviation due to temperature'-H △X109
...(n-4)) Rack 201 ・Magnetic disk 202...71'203
...nl) Degree detector 204...Signal converter 206.
Reference voltage generation circuit 208...Subtraction circuit 210...Amplification circuit 213...
Head moving mechanism drive circuit 214, head moving mechanism 215...carriage and above Applicant Suwa Seikosha Co., Ltd. Agent Patent attorney Tsutomu Mogami Figure 1 Figure 2

Claims (1)

[Claims] In a rotary magnetic recording/reproducing device that has a mechanism that allows fine adjustment of the head position to below the track width, a temperature sensor is attached to the device and the temperature is measured to calculate the head position error due to temperature expansion and determine the head position. A rotary magnetic recording/reproducing device characterized by correction.