JPH04116707A - Access command estimation/correction method, access controller and data transducer access controller - Google Patents

Abstract

PURPOSE:To easily and precisely estimate and correct an access command considering the influence of an actuator temperature in a short time by obtaining the acceleration command time of the access command fitted to a target shift distance with the actuator temperature and a target shift distance as variables. CONSTITUTION:A system consists of a logic circuit part 1, a driving circuit 6, an actuator 7, a position encoder 8, a position detection circuit 9, a speed detection circuit 10 and a temperature detection means 11. The actuator 7 is previously accessed as to the target shift distance on trial and the most fitted access command is estimated based on the access with the temperature of the actuator 7 and the target shift distance as the variables. Thus, the access command can easily and precisely be estimated and corrected in a short time by considering the influence of the rise of the temperature in the electromagnetic coil of the actuator 7.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention is directed to: Access command estimation method for actuators used in disk storage devices, etc. Access command correction method
Access control device and data transducer Access control device and data transducer Access control device and data transducer Access command estimation method for rapidly moving an actuator from a certain stop position to an arbitrary selected position Access control device and data transducer The present invention relates to an access control device.

2. Description of the Related Art Recently, the recording capacity of information recording and reproducing devices such as magnetic disk devices and optical disk devices has improved dramatically, and with this, there has been a demand for faster access to target information tracks by recording or reproducing data transducers. One of the access control methods for the positioning actuator of the information recording and reproducing device is the Bang-Bang drive method. Even if it is one method
, or ζ FIG. 9 is a block diagram of an actuator drive circuit in a conventional access control device. In FIG. 9, 91 is an operational amplifier, 92 is a power transistor, 93 is an electromagnetic coil of the actuator, 94 is an inductance component of the electromagnetic coil 93, and 95 is a pure resistance component RL96 of the electromagnetic coil 93.
97 is a current detection resistor that detects the value of the current flowing through the electromagnetic coil 93.
This is the back electromotive force generated at 3. This actuator drive circuit operates by feeding back one end of the current detection resistor 96 to the negative input of the operational amplifier 91.
An operation in which the current flowing through 3 is completely proportional to the positive input voltage of the operational amplifier 91.
However, this is when the drive circuit is operating in a linear region, and if a pan-pan command with a sufficiently large amplitude is applied to the input as shown in the figure, the operational amplifier 91 will become saturated, causing the drive circuit to become saturated. is in an open loop state and directly drives power transistor 92. As a result, the power transistor 92 (translation: saturated operation, that is, turns on), and a voltage obtained by subtracting the saturation voltage of the power transistor 92 and the voltage drop due to the current detection resistor 94 from the power supply voltage Ve is applied across the electromagnetic coil of the actuator. In this case, constant voltage operation is performed.

Here, if the influence of the inductance component 94 of the electromagnetic coil 93 and the influence of the back electromotive force 97 generated in the electromagnetic coil 93 due to movement of the actuator cannot be ignored,
The current flowing through the electromagnetic coil 93 is affected by the following effects. Immediate plate Pan-pan command plate Table 6 In places where the rectangular waveform command value changes rapidly, the current does not change immediately due to the influence of the inductance component 94 (also, it is proportional to the speed of the actuator's moving part). However, the magnitude of the back electromotive force 97 increases, but the voltage applied to the electromagnetic coil 93 decreases in the first half of the acceleration section of the pan-pan command shown in Figure 9, and increases in the second half of the deceleration section, respectively. FIG. 10 shows a side view of a DC-driven actuator generally called a voice coil motor.

In Fig. 10, 101 is an electromagnetic coil/l, 102
are magnets that supply a bias magnetic field to the electromagnetic coil 101. Magnets 103 and 104 are a center yoke and an outer yoke for receiving the magnetic flux generated by the magnet 102 to form a magnetic circuit, and are made of a material with high relative magnetic permeability such as iron. The operating principle of the actuator shown in the same figure is based on Fleming's left-hand rule.
The electromagnetic coil 101 moves in the direction shown by the arrow as the magnetic flux generated by the magnet 102 interlinks with the current flowing through the actuator 1.a The pure resistance value of the electromagnetic coil 101 of the actuator shown in Fig. 10 is This changes due to the influence of the environmental temperature in which the actuator is placed, or the fact that the electromagnetic coil itself generates heat due to the current flowing through the electromagnetic coil 101. In particular, the heat generation effect caused by the current depends on the number of repeated accesses and the current capacity flowing per one access. Figure 11 shows an example of the temperature rise characteristics of the electromagnetic coil 101 when the above-mentioned actuator is continuously accessed. However, the access distance is the same distance. In FIG. 11, the horizontal axis represents the one-way access distance per trip. Also, the vertical axis shows that by repeatedly accessing that distance for a certain period of time,
The temperature of the electromagnetic coil 101 increases and the temperature increase from the initial temperature at the time when the temperature increase is balanced is shown. The downtime given as a parameter means the time during which access is suspended between one one-way access and the next one-way access.As shown in Figure 11, the longer the access distance and the shorter the downtime. Figure 12 shows the waveforms of the current flowing through the electromagnetic coil 101, the actuator movement speed V, and the actuator movement distance X when the actuator is accessed using the pan-pan drive method. FIG. 2 is a diagram in which the horizontal axis represents time. East of the same figure The solid line indicates the case where the temperature of the electromagnetic coil increases due to an increase in the actuator's environmental temperature or the heat generation effect due to the current, and the broken line indicates the case where there is no effect. Although it shows a certain case, in Figure 12, the pure resistance value increases because the temperature of the electromagnetic coil increases.On the other hand, the voltage across the electromagnetic coil is constant, so even if the amount of current flowing through the electromagnetic coil decreases, the result is Compared to the case without temperature rise, the overall movement speed becomes smaller,
Problems to be Solved by the Invention Even if the Traveling Distance is Smaller: Strength When there is no temperature change in the electromagnetic coil and there is no influence of the inductance component and back electromotive force of the electromagnetic coil, <! If the pure resistance value of the electromagnetic coil is measured in advance, the access command for accurately accessing the actuator to the target position can be obtained using simple arithmetic operations. However, due to temperature changes in the electromagnetic coil,
Furthermore, if there are effects of inductance components and back electromotive force, when accessing the actuator by giving a pan-pan command, it is necessary to estimate the accurate acceleration time and deceleration time corresponding to the target travel distance at that time. In addition, in order to smoothly position toward the target, it is desirable that the movement speed when approaching the target position be almost zero. In such cases, it is actually quite difficult to estimate the acceleration and deceleration times in a short time and with high accuracy so that the movement speed becomes zero at the target position. This makes it difficult to realize access control devices using conventional methods.
The present invention has a problem in that it is difficult to perform appropriate access due to changes in the temperature of the electromagnetic coil due to an increase in the environmental temperature of the actuator or the heat generation effect of the current, and the influence of the inductance component and back electromotive force of the electromagnetic coil. The purpose of this is to solve the above-mentioned problems, and to estimate and correct access commands taking into account the effects of the temperature rise of the actuator's electromagnetic coil, the inductance component of the electromagnetic coil, and the back electromotive force in an extremely short time, in an easy version, and with high accuracy. Access command estimation method and access command correction method An object of the present invention is to provide an access control device and a data transducer access control device.

Means for Solving the Problems In order to solve the problems described above, the present invention uses the following methods\or has the following configuration.
Immediately, based on an access command including predetermined acceleration and deceleration commands necessary to move the actuator a predetermined target travel distance, the actuator is accessed a finite number of times for a certain target travel distance, and the target travel distance is determined. A force that determines the acceleration command time of an access command that is compatible with the actuator temperature and the target movement distance as variables, or includes predetermined acceleration and deceleration commands necessary to move the actuator by a predetermined target movement distance. The acceleration command time of the access command is corrected based on a correction table in which the actuator temperature and the target movement distance are input variables, and the correction of the acceleration command time of the access command is the output variable.
a position detection means for detecting the position of the movable part of the actuator, a temperature detection means for detecting the actuator temperature, a logic means for managing the movement of the actuator in accordance with a movement command from an external device, and an output of the logic means. a drive means capable of freely moving the actuator based on the logic means; the logic means uses the actuator temperature and the target movement distance of the actuator as input variables; and the correction portion of the acceleration command time of the access command should be the output variable. A force ＼ or G consisting of a correction table means for the access command.
A data transducer capable of reproducing at least information recorded on a plurality of recording tracks on a recording medium, an actuator capable of freely moving the data transducer, the recording medium and the data transducer. a position detection means for detecting the relative position with respect to the user; a temperature detection means for detecting the actuator temperature;
The actuator is configured to include logic means for managing the movement of the actuator according to a movement command from an external device, and a drive means that can freely move the actuator based on the output of the logic means, and the actuator temperature and a manual variable with the target movement distance of the actuator; and a correction amount of the acceleration command time of the access command as an output variable; The invention has the following effects by using the method or structure described above. Joint plate Trially accesses the actuator for a predetermined target movement distance, estimates the most suitable access command based on the access command using the actuator temperature and the target movement distance as variables, and uses the result to estimate the access command that is the most suitable for the actuator temperature and the target movement distance. By correcting the access command based on a correction table that uses the travel distance as an input variable and the correction of the acceleration command time of the access command as an output variable, it is possible to eliminate the effects of temperature rise in the electromagnetic coil of the actuator, which has been difficult in the past. Estimation and correction of access commands taking into account the influence of the inductance component of the electromagnetic coil and the back electromotive force can be easily and accurately performed in short hours. FIG. 2 is a flowchart diagram illustrating one embodiment of a method. The procedure will be explained below with reference to FIG.

As the target movement distance Xd that the actuator should move,
Decide on a certain typical size. For example (L: Divide the maximum movable range X max of the actuator movable part into m equal parts,
A set of m+1 target movement distances XdQ, Xdl,...
・, Xdm (m is a natural number XdO<Xdl<・<xd
m) However, 0≦) (di≦Xmax ・ ・ (1)
(1 = 1, ... m) First, perform the following procedure under the condition that the actuator temperature is TcO.However, the actuator temperature is the environmental temperature of the actuator, the driving part of the actuator The strength, which can be defined in various ways, such as the temperature of the frame for supporting the electromagnetic coil. First, give to as the acceleration time of the pan-pan command required to move the distance XdO. The acceleration time required to move a distance of XdO can be calculated using the following formula: to=(XdO/α)1″ (2) where α is the acceleration storm of the actuator and the movement of the actuator. After moving the part to the origin x = 0, access the actuator using an access command that accelerates for a time to and then decelerates until the moving speed V becomes zero.
Calculate the difference δXdO from the distance X drO actually traveled up to the point of 0 using the following formula 4δXdO = XdO - Xdr
O... (3) If the size of δXdO is sufficiently small, store the pair ii (XdOtQ, Tc0) in the data memory. Otherwise, increase i;LtQ by a certain size δt, and t o = t o+δt ・ ・ ・
(4), access the actuator again, and repeat the above procedure until the size of δXdO becomes sufficiently small. Furthermore, execute the same procedure for the above Xdl, ... Xdm, and obtain δXdi. (XdL, ti, T
Store the set of (XdL) in the data memory described above. Tcj)
Store the set in data memory. (Just Li=0,
■、... Nail Kasu j=1, ``n, n is a natural number,
f = T co < Tcl <-・< TCTI) If the actuator has variations in the generated force depending on the direction of movement, the above procedure can be carried out in the same way for both directions of movement, but Fig. 2 is similar to the one above. (XdL.

tL Tcj); FIG. In Figure 2, the vertical axis is the acceleration time t, and the horizontal axis is the temperature Tc. Even if the target travel distance The relationship cL between (acceleration time and temperature) for the case is almost linear as shown by the broken line. Therefore,
The acceleration time at any temperature can be determined by linear interpolation from the relationship shown in Figure 2. It is possible to estimate the acceleration time of an access command that is adapted to the temperature. The reason is to compensate for individual differences such as manufacturing tolerances of actuators and variations in electronic circuits.

Next, an embodiment of the access command correction method of the present invention will be described with reference to the drawings. FIG. 3 is a flowchart showing an embodiment of the access command correction method of the present invention. The procedure will be explained below with reference to Fig. 3.However, regarding the relationship between the actuator's target movement distance, acceleration time, and actuator temperature (Xdi, tL, Tcj) used in the following explanation, that is, the relationship shown in Fig. 2. The number of steps is to store the number of bundles in a data memory, etc. using the access command estimation method described above.In Fig. 3, first set the target movement distance Xd that the actuator should move. The acceleration time t of the pan-pan command necessary to move the target movement distance Xd when the actuator temperature is a certain arbitrary temperature Tc just before the actuator is moved is calculated by interpolation, etc. based on the relationship shown in Fig. 2 stored in the data memory. Find it using the method. The actuator is accessed with the access command for the acceleration time t obtained as described above, and when the moving speed of the movable part becomes less than a certain value or becomes zero, the positioning control of the movable part is performed to perform a series of access operations of the actuator. complete.

However, in the method of one embodiment of the present invention shown in FIG.
Since we have not considered setting an acceleration time for an arbitrary target movement distance, we will actually adopt another embodiment as shown below.

FIG. 4 is a flowchart showing another embodiment of the access command correction method of the present invention.The procedure will be described below with reference to FIG.

First, based on the comparison diagram in Figure 2, we set the rate of change in acceleration time per unit temperature change rt/Tc as shown in Figure 5.
A comparison diagram showing the relationship between the target movement distance Xd and the target movement distance Xd is obtained in advance. On the other hand, a comparison diagram showing the relationship between the target moving distance Xd and the acceleration time t at room temperature (25° C.) as shown in FIG. 6 is also obtained in advance. And the relationship between each
Store it in data memory, etc.

Next Perform the following steps when accessing the actuator: Joint plate Target travel distance X at room temperature
The acceleration time t suitable for accessing d can also be found using a method such as interpolation based on the relationship shown in Figure 6. Based on Figure 5, the ratio "t/Tc" is
Obtained using methods such as interpolation calculations. Using this, the correction amount δt of the acceleration time at the actuator temperature Tc can be calculated using the following formula: δt = Rate of change (t/Tc) x Temperature (Tc) Then, this correction amount δt is added to the acceleration time t, and 1 = 1+δt
... (6) and access is performed based on this acceleration time t.

Actuator temperature ζ The environmental temperature of the actuator, the surface or internal temperature of the electromagnetic coil installed to drive the moving parts of the actuator, the temperature of the frame used to support the electromagnetic coil, etc. There are various detection methods for force forks. However, the detection method does not essentially affect the functions and effects of the raw material of the present invention. That is, the second
It is desirable that the relationship in the figure be the same as the temperature detection method used when previously obtained using the access command estimation method as described above. To explain, FIG. 7 is a block diagram of one embodiment of the access control device of the present invention. In this FIG. 7, 7 is an actuator, 8 is a position encoder that constantly detects the position of this actuator, and 9 is a position encoder. A position detection circuit 10 receives the output signal of the encoder and generates the position signal X. A speed detection circuit 10 generates the speed signal V based on the position signal X.
is a drive circuit that supplies current (2) for driving the actuator 7 mentioned above. Reference numeral 11 indicates the temperature of the actuator 7, that is, the environmental temperature of the actuator 7, the surface or internal temperature of an electromagnetic coil (not shown) provided to drive the movable part of the actuator tough, and a frame (not shown) for supporting the electromagnetic coil. The detected temperature signal Tc may be output in the form of a voltage.This temperature detection means 11 specifically includes a temperature sensing element such as a thermistor and its bias circuit. A device encoder 8 consisting of a device encoder 8 constantly detects the movement of the movable part of the actuator 7, and its output current position signal is a linear linear signal that represents the amount of displacement of the movable part relative to a predetermined reference point within the movable range over the entire movable range. Although it has a structure like a scale, 1 is a logic circuit section that receives a movement command P of the actuator from the Kube device and outputs a drive command U to the drive circuit 6, and a drive command generation circuit 2, a microcomputer 3. Correction table memory 4
, the position signal X, the speed signal V, and the temperature detection signal Tc1L are manually inputted to the interface circuit 5. Interface circuit 5
is mainly composed of a plurality of A/D converters (not shown), and receives and receives the above-mentioned signals and sends them to the microcomputer 3. A movement command P given from an external device is directly input to the microcomputer 3, including the access start position, target position, and movement direction of the actuator as parameters. The memory for temporarily storing data and the memory for storing a program for sequentially managing the operations of the microcomputer 3 are included in the microcomputer 3.Access control of the present invention configured as described above The device (above) is configured to be able to implement the access command estimation method and access command correction method described above, and its operation will be briefly explained below, but first, the operation when estimating an access command will be explained. Using an external device such as a constant temperature bath, the following procedure is executed while maintaining the temperature at a certain temperature Tc.First, the initial value of the acceleration time t for the target movement distance Xd is determined by the microcomputer based on equation (2). Next, after moving the movable part of the actuator 7 to the origin position, the actuator 7 is accessed on a trial basis for the target movement distance Xd, and the deviation δXd between the movement distance Xdr at that time and the target movement distance Xd is calculated. If it is not sufficiently small, a certain correction amount δt is added to the acceleration time t based on equation (4), and trial access is performed again.

Repeat this procedure until the optimal acceleration time t is obtained.
The obtained set of (Xd, t, TC) is sent to microcomputer 3.
Further, the magnitude of the target movement distance Xd is changed and the above procedure is repeated. Then, the temperature TC of the actuator tough is changed and the same procedure is repeated. Obtained by the above procedure (Xi
t, Tc) using the microcomputer 3 to calculate the relationship between the rate of change in acceleration time per unit temperature change and the target moving distance, that is, the relationship shown in FIG. 5, and store it in the correction table memory 4. Further, the relation between the target moving distance and the acceleration time at room temperature (25° C.), that is, the relationship shown in FIG. 6 is similarly held in the correction table memory 4.

Next, we will explain the operation when correcting an access command.
Each parameter value of the access start position Xs and the target position movement direction is extracted. However, the access start position Xd & the end point position of the previous access operation, that is, the current actuator 7
means the position where the movable part of is held. Then, the target movement distance Xd is calculated from the access start position Xs and the target position.The acceleration time at an arbitrary actuator temperature Tc is determined by the following procedure. First, the acceleration time t suitable for accessing the target movement distance The rate of change in acceleration time per unit temperature change corresponding to the target moving distance Then, the temperature Tc of the actuator 7 is detected by the temperature detection means 11, and based on equation (5), the microcomputer 3 performs an operation to multiply the temperature by the rate of change to correct the acceleration time. Calculate the amount δt.Based on equation (6), add this δt to the previously calculated acceleration time t at normal temperature to obtain the acceleration time t.Furthermore, the drive command U consisting of the acceleration time t calculated in this way is generated by the drive command generation circuit 2 and manually inputted to the drive circuit 6 to control the actuator 7 from the access control.
When the moving speed V of the movable part becomes less than a certain value or becomes zero, the series of access operations is completed by controlling the positioning of the movable part.

resistance correction table memory 4 (&EEP R
OM (Electrically Erasable
By employing a non-volatile memory such as a programmable ROM (and programmable ROM), the retained data can be used multiple times without being lost even after the access control device is powered off.

Next, an embodiment of the data transducer access control device of the present invention will be described with reference to the drawings, and FIG. 8 is a block diagram of an embodiment of the data transducer access control device of the present invention. In FIG. 8, 7 is an actuator, 21 is a disk-shaped recording medium, and 22 is a data transducer that can record or reproduce information recorded on a plurality of recording tracks on this recording medium 21. The unit 23 is provided so that it can access any recording track on the medium and follow the target recording track. A servo information demodulator receives the playback signal taken out by 22 and generates the position signal X. 24 is a switch for switching between the playback signal obtained from the data transducer 22 and the recording signal to the data transducer 22. , 10 is a speed detection circuit 6 that generates a speed signal V based on the position signal Temperature detection means that detects the surface or internal temperature of an electromagnetic coil (not shown) provided to drive the movable part of the actuator 7, the temperature of a frame (not shown) for supporting the electromagnetic coil, etc. The detected temperature signal Tc is output in the form of a voltage. Specifically, the temperature detection means 11 is composed of a temperature detection element such as a thermistor and its bias circuit. Upon receiving the actuator movement command P, the drive circuit 6
This is a logic circuit section that outputs a drive command U to the drive command generation circuit 2, the microcomputer 3, and the interface circuit 5. too
The interface circuit 5 is mainly composed of a plurality of A/D converters (not shown), and receives and receives the above-mentioned signals.
The -4 interface circuit 5 includes at least one D/A converter (not shown) and receives recording signals obtained from an external device (not shown) via the microcomputer 3. Take it and send it to switch 24. This recording signal is written to the data area of the recording medium 21 via the data transducer 22. The movement command P given from an external device includes the actuator's access start position, target position, and movement direction as parameters.It can also be input directly to the microcomputer 3.It is used to sequentially manage the memory for temporarily storing data and the operation of the microcomputer. The data transducer access control device of the present invention configured as described above is included in the microcomputer 3.
It is configured to be able to implement the access command estimation method and access command correction method described above, and its operation is almost the same as that of the access control device described above. Only the different points will be explained below. I will explain the operation when a trial access is performed and 01t, Tc)
The procedure up to storing the set in the memory (not shown) in the microcomputer 3 is exactly the same as in the embodiment of the access control device described above. In the present invention, the obtained data set 0
This access control device differs from the access control device described above in that (d, t, TC) is not held in the correction table memory but is recorded in a part of the data area of the recording medium 21.
. It is held in the correction table area provided. In addition, the relationship between the target movement distance and acceleration time at room temperature (25°C), that is, the relationship shown in Figure 6, is also maintained in the correction table area.Next, we will explain the operation when correcting the access command. Access command in the data transducer access control device of the invention (meaning the command necessary to move the actuator to move the table data transducer 22 from one information track to another; acceleration of this access command) Time (L) can be determined using the following procedure. First, at room temperature, target travel distance
The acceleration time t suitable for accessing d is calculated using methods such as interpolation calculation based on the relationship between the target moving distance and the acceleration time stored in advance in the correction table area on the recording medium 21, that is, the relationship shown in FIG. 4 people The rate of change in acceleration time per unit temperature change corresponding to the target movement distance Xd is ``t/
TC'' is determined using a method such as interpolation calculation based on the relationship shown in FIG. 5 held in the correction table area. The subsequent steps are the same as those of the access control device described above, so a description thereof will be omitted.

In the present invention, the data set (Xd, t, Tc)
By recording the data in a part of the data area of the recording medium 21 instead of storing it in the correction table memory, it is possible to retain the data set without any special measures even after the power of the device is turned off. The burden on the electronic circuit memory and its peripheral circuits can be reduced. The data transducer access control device of the present invention also has the advantage of not being subject to design limitations regarding the capacity of the electronic circuit memory even if the capacity of the data set becomes relatively large. In one embodiment, the position signal x is obtained by reproducing servo information on the recording medium 21 using the data transducer 22. As shown in the embodiment of the access control device of the invention, it is also possible to obtain the position signal X from the position encoder 8 attached to the movable part of the actuator. The length of the access command is not necessarily limited to this. It does not matter if the shape is such that there is a rest area where the distance is zero.
It is assumed that the access command correction is performed based on normal temperature.This is not necessarily the case, however, as described in detail of the invention, the present invention has the following excellent effects.

The actuator is accessed on a trial basis for a certain target travel distance, and based on that, the most suitable access command is estimated using the actuator temperature and the target travel distance as variables, and the results are used to calculate the actuator temperature and the target travel distance. By correcting the access command based on a correction table means using the target movement distance as a manual variable and the correction of the acceleration command time of the access command as an output variable, we were able to consider the influence of actuator temperature, which had been difficult in the past. Estimate and correct access commands in a short time
Although it can be done easily and accurately,

[Brief explanation of the drawing]

Fig. 1 41 A flow doctor showing an embodiment of the access command estimation method of the present invention Fig. 2 (a control doctor showing the relationship shown above (target movement distance, skin temperature during acceleration)) Fig. 3 is an access command correction method of the present invention Flow showing an example @ 4th
Figures 5 and 4 show a flow diagram showing another embodiment of the access command correction method of the present invention. A control diagram 6 shows the relationship between the rate of change in acceleration time per unit temperature change and the target moving distance.
The figure shows the relationship between the target movement distance and the acceleration time at room temperature. The blocks of one embodiment of the device are shown in Fig. 9 ζ. Fig. 10 ζ is a block diagram of the actuator drive circuit in a conventional access control device. Side view of a conventional actuator is shown in Fig. 11 (top). Figure 12 is a waveform diagram of the current flowing through the electromagnetic coil, the actuator moving speed V, and the actuator moving distance X. 1... Logic circuit a 2... Drive command generation circuit 3...
・Microcomputer, 4...Correction table memory, 5...
Interface times W1.6... Drive same area 7... Actuator 8... Position encoder, 9... Position detection same area 10... Speed detection same area 11... Temperature detection means, 21... - Recording medium 22... Data transducer, 23 - Servo information demodulation apposition 24...
・Sui Sochi. Name of agent Patent attorney Akira Okaji and 2 others ! Se H money

Claims (7)

[Claims] (1) Based on an access command including predetermined acceleration and deceleration commands necessary to move the actuator by a predetermined target movement distance, the actuator is accessed a finite number of times for a certain target movement distance, and the target movement is performed. An access command estimation method characterized in that an acceleration command time of an access command adapted to a distance is determined using an actuator temperature and the target movement distance as variables. (2) The access command estimation method according to claim (1), wherein the actuator temperature is determined based on the temperature of a drive electromagnetic coil of the actuator. (3) The acceleration command time of the access command including the predetermined acceleration and deceleration commands necessary to move the actuator by a predetermined target travel distance is set using the actuator temperature and the target travel distance as input variables, and the access command An access command correction method characterized in that the correction is performed based on a correction table in which an output variable is a correction amount of an acceleration command time. (4) The access command correction method according to claim (3), wherein the actuator temperature is determined based on the temperature of a drive electromagnetic coil of the actuator. (5) a position detection means for detecting the position of the movable part of the actuator, a temperature detection means for detecting the actuator temperature, a logic means for managing the movement of the actuator in accordance with a movement command from an external device, and this logic means and a drive means capable of freely moving the actuator based on the output of the logic means,
It is characterized by comprising a correction table means for the access command, which uses the actuator temperature and the target movement distance of the actuator as input variables, and uses the correction amount of the acceleration command time of the access command as an output variable. access control device. (6) A data transducer capable of reproducing at least information recorded on a plurality of recording tracks on a recording medium, an actuator capable of freely moving this data transducer, and a relative relationship between the recording medium and the data transducer. a position detection means for detecting the position; a temperature detection means for detecting the actuator temperature;
The actuator is configured to include logic means for managing the movement of the actuator according to a movement command from an external device, and a drive means that can freely move the actuator based on the output of the logic means, and the actuator temperature and Correction information for the access command is held on the recording medium, with the target movement distance of the actuator as an input variable and the correction of the acceleration command time of the access command as an output variable. A data transducer access control device characterized by: (7) The position detecting means includes servo information demodulating means provided to demodulate the servo information recorded on the recording track based on the output reproduced by the data transducer. 6) The data transducer access control device as described above.