JPS58194174A - Controlling system of positioning conversion head - Google Patents

Abstract

PURPOSE:To obtain a stable transient response regardless of the numbers of moving tracks, by changing the acceleration and deceleration in response to the accelerating and decelerating region of a moving position model, corresponding to the number of moved tracks. CONSTITUTION:The number of tracks from the track where a transducer head (e.g., magnetic head) is positioned at present to a track desired to be moved in future, is inputted to an acceleration and deceleration selecting loop 2 and a moving position model calculating loop 3. The optimum acceleration determined depending on the track number is calculated at the acceleration and deceleration selection loop 2, and it is fed to the moving position model calculating loop 3. A feedforward signal determined on the signal value applied to a feedforward signal calculating loop 4 is applied from the calculating loop 3, and a signal corresponding to the sum of the feedforward signal is applied from a power amplifier 12 to a voice coil motor 8 to drive it. Since this driving signal includes the optimum acceleration determined depending on the number of moved tracks, the transient response from the movement with less number of moved tracks to that with many moved tracks is made stable, and the positioning is attained in the possible shortest time regardless of the number of moved tracks.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a transducing head positioning control system that improves the driving manner of a transducing head driving means in positioning a transducing head to a desired recording track.

(2) 6 Background of the Invention Until now, the control method for the random access mechanism of the magnetic head in a magnetic disk device was an analog servo method, but in recent years various digital servo methods have been developed and put into practical use. .

Among these digital servo methods, in the control method of the magnetic head that utilizes the movement position, it is difficult to reach one track due to the delay of the drive motor that occurs when the number of moving tracks of the magnetic head is small. Since undesirable operating conditions sometimes occur, it is desirable to develop technical means to solve these problems.

(3), prior art and t! One problem: In the conventional control system, the delay of the drive motor is caused by the motor's current/ductance. Such a delay in the drive motor causes the following problems when it is desired to move the head at high speed. νOne, when the number of moving trunks is small, only a short time of several ma, c is allowed for the movement, but the electrical time constant of the commonly used voice coil motor is about lm5sc, so this is ignored. And you won't get it.

As a result, undesirable phenomena in terms of control occur, such as undershoot and overshoot occurring when reaching the target track.

(4) 9 Purpose of the Invention The present invention was created in view of the technical problems encountered, and its purpose is to provide a transducer head that can exhibit stable transient response even when the number of track movements is small or large. There is a VC that provides a positioning control force formula.

(5) 5 Structure of the Invention And, this object is to provide a conversion head positioning method in which the conversion head is moved following a movement position model when positioning the conversion head to an arbitrary recording track. This is achieved by changing the acceleration and deceleration corresponding to the deceleration region VC in accordance with the number of trunks being moved.

(6) Example of 1 invention The present invention will now be described in detail with reference to the appendix.

The accompanying drawings illustrate an embodiment of the invention. 1 is a microprocessor having an acceleration/deceleration value selection loop 2, a movement position model calculation root 3, and a feedforward signal calculation loop 4.

A line 5 is connected to the acceleration/deceleration value selection root 2 and the moving position model 1n loop 3, which sends the number of moving tracks. The mobile position model calculation loop 3 is connected to the subtractor 6's ten-point line 7, to which a position signal of the mobile position model is generated.

A feedback root 9 from a voice coil motor 8 is connected to the single power of the subtractor 6, and a position [-L sensor lO is interposed in this feedback root 9.

The output of the subtracter 6 is connected to one of the power amplifiers 12 through the compensation circuit 11, and the other input is connected to the line 13.
7 to the output of the feedforward signal calculation loop 4. The output of power amplifier 12 is connected to the input of voice coil motor 8.

Next, the operation of the apparatus implementing the present invention having the above configuration will be explained.

The current transducer head (
For example, if the magnetic head) is in position 1iIt1. .

The number of tracks from the current track to the track to be moved is input into acceleration/deceleration value selection loop 2 and movement position model calculation loop 3. Acceleration/deceleration value selection loop 2
The optimum acceleration magnitude Ig determined according to the number of tracks is
zl is awarded and given to the moving position model calculation loop 3.

In moving position model calculation loop 3, the number of moving tracks and +
-s+\, the difference (error amount) between the moving position model position signal determined by these, ftA7kK generation j7, and the value from the generated value 7 feedback roots 9 is sent to one side of the power amplifier 12 via the compensation circuit 11. -4- is supplied to the human power, while the other ten inputs are supplied from the moving position model calculation roots 3 to the feedforward signal calculation loop 4 (a feedforward signal determined by the m value is supplied, and the sum of A signal having a value corresponding to ' is applied from the power amplifier 12 to the voice coil motor 8 to drive it.

Since the drive number δ includes acceleration components 1-11, which are determined according to the number of moving tracks as described above, the control system of the present invention The transient response is stable from to a large number of movements, and positioning can be achieved within the shortest possible time regardless of the number of moving tracks.

Moreover, compared to the conventional side wing system that switches between speed control and position control, the two control system is not only simpler, but also allows the introduction of the processor as described above.

In the above embodiment, each loop 2.3 and 4 is
Of course, although the TC is formed inside the sensor, it can be constructed by providing different hardware.

(7) Effects of 1 invention In summary, according to the present invention.

0) A stable transient response can be obtained regardless of the number of moving tracks, and θ) The control system can be simplified, which can pave the way for the introduction of processors.

[Brief explanation of drawings]

The accompanying drawings illustrate one embodiment of the invention. In the figure, 2-digit acceleration/deceleration value selection loop 3 is a moving position model calculation loop, 4 is a feedback A word signal calculation loop, 6 is a subtracter, 9 is a feedback loop, 11 is a compensation circuit, 12 is a TF power amplifier, and 8 is a voice It is a coil motor. Patent applicant Fujitsu Limited

Claims (1)

[Claims] In a conversion head positioning method in which the conversion head is moved following a movement position model when positioning the conversion head to an arbitrary recording track, acceleration and deceleration corresponding to acceleration areas and deceleration areas of the movement position model are moved. A converting head positioning control method characterized in that the conversion head positioning control method is changed according to the number of tracks to be moved.