JP2011028820A - Optical disk drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk drive, wherein the number of revolutions of disk is not greatly lowered and also the current consumption is suppressed. <P>SOLUTION: The optical disk drive includes a spindle motor 12 and a thread motor 18. By a system controller 32, the spindle motor 12 is rotationally driven with a first rotation driving current when no seeking operation exists, and when performing seek to a first direction, the driving current for the spindle motor 12 is reduced to a second rotation driving current which is smaller than the first rotation driving current, and also a movement driving current of the thread motor 18 is defined as a first movement driving current and when performing seek to a second direction which requires a small driving torque, the movement driving current of the thread motor 18 is defined as a second movement driving current which is smaller than the first movement driving current. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical disc apparatus, and more particularly to suppression of current consumption.

  In an optical disc apparatus, reduction of current consumption is required. In particular, in an optical disk device (disk drive) connected to a notebook personal computer via USB, the maximum current consumption is determined by the USB standard (for example, 500 mA), and the current consumption of the optical disk device is limited to the maximum current consumption. There is a need.

  Patent Document 1 discloses a method for controlling the drive of an actuator in a hard disk drive. That is, by increasing the drive current supplied to the voice coil motor (VCM) that is the actuator drive source during head unloading, the torque during head unloading can be increased and the power consumption during seek operation can be suppressed. It is disclosed.

  Further, Patent Document 2 discloses that the drive current supply to the spindle motor is stopped during the coarse seek operation by the thread motor, and the drive current supply stop to the spindle motor is released after the coarse seek operation is completed. ing.

Japanese Patent Laid-Open No. 2005-158097 JP 2001-76764 A

  However, Patent Document 1 only describes a drive current at the time of head unloading, and only a uniform drive current is described for a seek operation in an area where data is recorded / reproduced.

  Also, in Patent Document 2, it is possible to reduce the overall current consumption by adding the current consumption in the sled motor and the current consumption in the spindle motor by stopping the supply of drive current to the spindle motor during the seek operation. However, if the drive current supply to the spindle motor is stopped, the disk rotation speed decreases due to friction. If the seek operation is performed continuously, the disk rotation speed will decrease significantly, and in some cases, playback may be difficult. It can be impossible.

  An object of the present invention is to provide an optical disc apparatus that suppresses current consumption without significantly reducing the rotational speed of the disc.

The present invention is an optical disc apparatus for recording or reproducing data on an optical disc, wherein the optical disc is driven to rotate, a drive unit for moving and driving an optical pickup along a radial direction of the optical disc, When the movement drive means is not driving the optical pickup, the rotation drive means rotates the optical disk with a first rotation drive current, and the movement drive means drives the optical pickup in the first direction. The rotational drive current of the rotational drive means is reduced to a second rotational drive current smaller than the first rotational drive current, and the travel drive current of the travel drive means is used as the first travel drive current, and the travel drive The second means has a driving torque that is opposite to the first direction and requires less driving torque than the first direction. And the second driving current of the moving driving means is smaller than the first moving driving current, and the rotating driving current of the rotating driving means is used as the second rotating driving current. And a control means.
In one embodiment of the present invention, the control means uses a rotation drive current of the rotation drive means based on the second rotation drive current when the movement drive means drives the optical pickup in the second direction. The third rotational drive current is larger and smaller than the first rotational drive current, and the travel drive current of the travel drive means is the second travel drive current.

  In addition, the present invention further includes a step-out detection unit that detects a step-out of the movement drive unit, and the control unit detects the step-out when the step-out detection unit detects the step-out. At least one of the following movement drive current, the second movement drive current, the second rotation drive current, and the third rotation drive current is changed.

  According to the present invention, the current consumption is suppressed without significantly reducing the rotational speed of the disk.

It is a configuration block diagram of an embodiment. It is a top view of the seek structure of an embodiment. It is a detailed perspective view of the tooth | gear formation member in FIG. FIG. 3 is a side view of FIG. 2. It is a processing flowchart of an embodiment. It is another process flowchart of embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows the overall configuration of the optical disc apparatus according to this embodiment. An optical disk 10 such as a CD, DVD, or Blu-ray is driven by a spindle motor (SPM) 12. The spindle motor SPM 12 is driven by a driver 14, and the driver 14 is servo-controlled by a servo processor 30 so as to have a desired rotation speed.

  The optical pickup 16 includes a laser diode (LD) for irradiating the optical disk 10 with laser light and a photodetector (PD) that receives reflected light from the optical disk 10 and converts it into an electrical signal, and is disposed opposite to the optical disk 10. . The optical pickup 16 is driven in the radial direction of the optical disk 10 by a sled motor 18 constituted by a stepping motor, and the sled motor 18 is driven by a driver 20. The driver 20 is servo-controlled by the servo processor 30 similarly to the driver 14. The LD of the optical pickup 16 is driven by a driver 22, and the driver 22 is controlled by an auto power control circuit (APC) 24 so that the drive current becomes a desired value. The APC 24 and the driver 22 control the light emission amount of the LD according to a command from the system controller 32. In FIG. 1, the driver 22 is provided separately from the optical pickup 16, but the driver 22 may be mounted on the optical pickup 16.

  When data recorded on the optical disk 10 is reproduced, a laser beam of reproduction power is irradiated from the LD of the optical pickup 16, and the reflected light is converted into an electric signal by the PD and output. A reproduction signal from the optical pickup 16 is supplied to the RF circuit 26. The RF circuit 26 generates a focus error signal and a tracking error signal from the reproduction signal and supplies them to the servo processor 30. The servo processor 30 servo-controls the optical pickup 16 based on these error signals, and maintains the optical pickup 16 in an on-focus state and an on-track state. Further, the RF circuit 26 supplies an address signal included in the reproduction signal to the address decoding circuit 28. The address decoding circuit 28 demodulates the address data of the optical disk 10 from the address signal and supplies it to the servo processor 30 and the system controller 32.

  The address signal is, for example, a wobble signal, and address data is obtained by extracting the wobble signal from the reproduction signal and decoding it. Further, the RF circuit 26 supplies the reproduction RF signal to the binarization circuit 34. The binarization circuit 34 binarizes the reproduction signal and supplies the obtained signal to the encoding / decoding circuit 36. The encode / decode circuit 36 demodulates the binary signal and corrects errors to obtain reproduction data, and outputs the reproduction data to a host device such as a personal computer via the interface I / F 40. When the reproduction data is output to the host device, the encoding / decoding circuit 36 temporarily stores the reproduction data in the buffer memory 38 and outputs it.

  When data is recorded on the optical disk 10, data to be recorded from the host device is supplied to the encode / decode circuit 36 via the interface I / F 40. The encode / decode circuit 36 stores data to be recorded in the buffer memory 38, encodes the data to be recorded, and supplies the data to the write strategy circuit 42 as modulated data. The write strategy circuit 42 converts the modulation data into a multi-pulse (pulse train) according to a predetermined recording strategy, and supplies it to the driver 22 as recording data. Since the recording strategy affects recording quality, optimization is performed prior to data recording. The laser light whose power is modulated by the recording data is irradiated from the LD of the optical pickup 16 and the data is recorded on the optical disk 10. The recording power during data recording is optimized by trial writing test data using a PCA (Power Calibration Area) formed on the inner circumference side of the optical disc 10 by OPC (Optical Power Control). . After recording the data, the optical pickup 16 reproduces the recorded data by irradiating a laser beam with a reproduction power, and supplies it to the RF circuit 26. The RF circuit 26 supplies the reproduction signal to the binarization circuit 34, and the binarized data is supplied to the encode / decode circuit 36. The encoding / decoding circuit 36 decodes the modulated data and collates it with the recording data stored in the buffer memory 38. The result of the verification is supplied to the system controller 32. The system controller 32 determines whether to continue recording data or execute a replacement process according to the result of verification. The system controller 32 controls the operation of the entire system, drives the sled motor 18 via the servo processor 30, and controls the position of the optical pickup 16. Further, the system controller 32 optimizes the recording power by controlling the OPC.

  As described above, the optical disk 10 is rotationally driven by the spindle motor 12. The spindle motor 12 is driven by the driver 14, while the optical pickup 16 is driven by the thread motor 18, and the thread motor 18 is driven by the driver 20. When a write command or a read command is issued from the host and the optical pickup 16 is moved (seek) along the radial direction of the optical disc 10 to execute these commands, the current consumed by the spindle motor 12 and the thread motor 18 are changed. Current consumption is added, and the total current consumption increases.

  On the other hand, if the drive current supply of the spindle motor 12 is stopped during the seek operation of the optical pickup 16, the rotational speed of the optical disk 10 is lowered, and the reproduction operation may be hindered.

  Therefore, in the present embodiment, even during the seek operation of the optical pickup 16, the seek operation is performed to supply the drive current to the spindle motor 12 to suppress the decrease in the rotational speed of the optical disc 10 and to reduce the overall current consumption. The current consumption at the time is increased or decreased according to the change in the required torque during the seek operation.

  Hereinafter, a change in required torque during the seek operation of the optical pickup 10 will be described.

  The optical pickup 10 is driven by a thread motor 18 and specifically includes a stepping motor and a lead screw.

  2 and 3 show an example of the drive mechanism of the optical pickup 12. The optical head 50 is held on the upper surface of the head base 52. The head base 52 is provided between a round bar-shaped main guide bar 58 a and a sub guide bar 58 b arranged in parallel to the radial direction of the optical disc 10, and is formed in a circular shape formed on one side surface of the head base 52. The main guide bar 58a passes through the guide hole 54, and the sub guide bar 58b is accommodated in a semicircular guide portion 56 formed on the other side surface, and is slidably supported on the guide bars 58a and 58b.

  A lead screw 60 is provided in the vicinity of the main guide bar 58a so as to be parallel to the main guide bar 58a. A spiral groove 60a is formed on the outer peripheral surface of the lead screw 60, and a stepping motor 61 is attached to the end.

  As shown in FIG. 3, the tooth forming member 62 includes a coupling portion 63 attached to the head base 52, a slide portion 64 slidable on the main guide bar 58 a, and teeth 72 that mesh with the spiral groove 60 a of the lead screw 60. The movable plate 66 is formed. A connecting portion 63 is provided at the upper end of one side surface of the slide portion 64 with the guide surface facing downward, and a movable plate 66 is provided at the lower end of the other side surface so as to be folded back via a bent portion 74. The tooth forming member 62 is configured so that an opening (not shown) formed on the upper surface of the guide hole 54 of the head base 52 is covered with the slide portion 64, and the movable plate 66 is disposed on the lead screw 60 side. The head 68 is attached to the head base 52 by tightening a screw 68 in a screw hole 76 formed in the coupling portion 63. As a result, the slide portion 64 contacts the main guide bar 58a penetrating the guide hole 54 of the head base 52 in a slidable manner.

  The lower end of the movable plate 66 is integrally formed with the slide portion 64 via the bent portion 74, and the upper end is a free end. Two teeth 72 that mesh with the spiral groove 60 a of the lead screw 60 are formed on the surface 66 a of the movable plate 66. Further, a projection 78 is formed on the back surface 66 b of the movable plate 66, and a convex portion 80 is formed on the slide portion 64 toward the projection 78. Both ends of the coil spring 70 are attached to the protrusion 78 and the protrusion 80, respectively.

  When the head base 52 is moved in the radial direction of the optical disk 10 (seek), the stepping motor 61 is driven and the lead screw 60 is rotated. Since the spiral groove 60a of the lead screw 60 and the teeth 72 of the tooth forming member 62 are in mesh with each other, the tooth forming member 62 converts the rotational power of the lead screw 60 into power to translate the optical disk 10 in the radial direction, The head base 52 to which the tooth forming member 62 is attached slides on guide bars 58 a and 58 b provided so as to be parallel to the lead screw 60.

  FIG. 4 is a side view showing a state when the lead screw 60 is rotating. When the rotation direction of the lead screw 60 is the A direction in the drawing, the spiral groove 60a of the lead screw 60 and the teeth 72 mesh with each other. As a result, the movable portion 66 is against the coil spring 70 on the back surface 66b side with respect to the hinge shaft 84. Rotate to. Then, the movable portion 66 is relatively strongly biased by the lead screw 60 due to the elastic force of the coil spring 70, so that the torque required for rotation increases. On the other hand, when the rotation direction of the lead screw 60 is B in the figure, the movable portion 66 rotates to the surface 66a side, so the urging force of the coil spring 70 is weakened and the torque required for rotation is reduced. Since the rotation direction of the lead screw 60 is uniquely determined with respect to the seek direction, the torque required for rotation increases or decreases according to the seek direction.

  Thus, the required torque changes according to the seek direction during the seek operation. In this embodiment, paying attention to this change, the drive current is increased when seeking the optical pickup 10 in the direction where the required torque is large. When the optical pickup 10 seeks in a direction where the required torque is small, the drive current is reduced. In order to reliably seek the optical pickup 10, it is possible to set the driving current of the stepping motor uniformly on the basis of the case where the required torque is large. However, when the required torque is small, excessive driving current is consumed. It will be. Therefore, the current consumption can be suppressed by adaptively increasing / decreasing the driving current of the stepping motor according to the magnitude of the required torque.

  On the other hand, it is preferable to suppress the drive current of the spindle motor 12 during the seek operation, but simply suppressing it may cause a decrease in the rotational speed of the optical disc 10. Therefore, the amount of suppression of the drive current of the spindle motor 12 is reduced by the amount that the drive current of the stepping motor is reduced when the required torque is small. This effectively suppresses a decrease in the rotational speed of the optical disc 10.

  FIG. 5 shows a processing flowchart of the present embodiment. First, when there is no seek operation, the drive current of the spindle motor (SPM) and the rotation speed of the optical disc 10 are controlled (S101). That is, the drive current of the spindle motor (SPM) 12 is controlled so that the optical disk 10 has a desired rotational speed. At this time, the seek current, that is, the drive current of the thread motor 18 (stepping motor in the case of a stepping motor and a lead screw) is zero.

  Next, it is determined whether or not there is a seek start command (S102). If there is a seek command, the system controller 32 determines whether or not the seek direction related to the seek command is a direction in which the torque is large (a direction requiring a large torque) (S103). In the case where a large torque is required, the system controller 32 sets the seek current and the drive current of the spindle motor (SPM) 12 for large torque (S104). If the seek direction is not a direction in which the torque is large, the seek current and the drive current of the spindle motor (SPM) 12 are set for a small torque (S105).

  For example, if the drive current of the spindle motor (SPM) 12 when there is no seek operation is 250 mA, the drive current of the spindle motor (SPM) 12 is 250 mA (first rotation) when the seek direction is the direction of large torque. The drive current is reduced to 100 mA (second rotational drive current), and the seek current is set to 150 mA (first movement drive current). When the seek direction is a direction with a small torque, the drive current of the spindle motor (SPM) 12 is reduced from 250 mA (first rotation drive current) to 100 mA (second rotation drive current), and the seek current is reduced. Is reduced from 150 mA (first movement driving current) to 100 mA (second movement driving current). Alternatively, as a second setting method, when the seek direction is a direction with a small torque, the drive current of the spindle motor (SPM) 12 is changed from 250 mA (first rotation drive current) to 150 mA (third rotation drive current). And the seek current is reduced from 150 mA (first movement drive current) to 100 mA (second movement drive current). It should be noted that in the second setting method, the drive current of the spindle motor (SPM) 12 is increased by 150 mA and 50 mA instead of 100 mA. This is because the difference of 50 mA is distributed to the drive current of the spindle motor (SPM) 12 as the seek current is reduced from 150 mA to 100 mA in accordance with the small torque.

  In the second setting method, as the seek current is reduced from 150 mA to 100 mA according to the small torque, this difference of 50 mA is not all allocated to the drive current of the spindle motor (SPM) 12, but a part thereof. You may sort only. For example, only 30 mA of 50 mA is distributed and the drive current of the spindle motor (SPM) 12 is set to 130 mA. In either case, the drive current increases compared to the case where the drive current is 100 mA, and the decrease in the rotational speed of the optical disc 10 can be suppressed by that amount.

  After setting the seek current and the drive current of the spindle motor (SPM) 12 according to the seek direction as described above, the seek operation is started (S106). After the seek is completed (S107), the processing after S101 is repeated again.

  In this embodiment, when the required torque differs depending on the seek direction as described above, the drive current in the direction with the large torque and the drive current in the direction with the small torque are not made the same, and the drive current in the direction with the small torque is reduced according to the torque. This reduces the overall current consumption. Normally, when the required torque is large or small, the drive current is set based on the case where the torque is large (this is used as the reference drive current), but when the torque is small, the drive current becomes excessive and increases the overall current consumption. To do. In this embodiment, when the torque is small, the reference drive current is not maintained as it is, but the overall current consumption is reduced by reducing the reference drive current. Further, in the case where the drive current is reduced below the reference drive current, the decrease is distributed to the drive current of the spindle motor (SPM) 12, so that the reduction in the rotational speed of the optical disk 10 can be suppressed while the overall current consumption is suppressed.

  FIG. 6 shows another processing flowchart of the present embodiment. In this process, when the sled motor 18 is composed of a lead screw and a stepping motor, the drive current is changed according to the presence or absence of step-out.

  First, when there is no seek operation, the drive current of the spindle motor (SPM) and the rotational speed of the optical disc 10 are controlled (S201). That is, the drive current of the spindle motor (SPM) 12 is controlled so that the optical disk 10 has a desired rotational speed. At this time, the seek current, that is, the drive current of the thread motor 18 (stepping motor in the case of a stepping motor and a lead screw) is zero.

  Next, the system controller 32 determines whether or not the step-out history has not been updated (S202). If there is an update of the step-out history (if NO is determined in S202), it is further determined whether or not the set value has been changed (S203). If the set value has not been updated, the torque is large or small. In each case, the seek current and the drive current of the spindle motor (SPM) 12 are changed according to the step-out history, and the fact that the setting has been changed according to the step-out history is recorded in the memory (S204). Specifically, the change according to the step-out history is to increase the seek current in the seek direction by a predetermined amount when step-out occurs when seeking.

  If the step-out history has not been updated, or if the step-out history has been updated and the set value has been changed accordingly, it is next determined whether or not there has been a seek start command (S205). If there is, it is further determined whether or not the torque is required (S206). That is, it is determined whether or not the seek direction according to the seek command is a direction in which the torque is large (a direction in which a large torque is required). When the direction in which a large torque is required, the system controller 32 sets the seek current and the drive current of the spindle motor (SPM) 12 for large torque (S207). If the seek direction is not a direction in which the torque is large, the seek current and the drive current of the spindle motor (SPM) 12 are set for a small torque (S208).

  For example, if the drive current of the spindle motor (SPM) 12 when there is no seek operation is 250 mA, the drive current of the spindle motor (SPM) 12 is reduced from 250 mA to 100 mA when the seek direction is a direction of large torque. At the same time, the seek current is set to 150 mA. When the seek direction is a direction with a small torque, the drive current of the spindle motor (SPM) 12 is reduced from 250 mA to 100 mA, and the seek current is reduced from 150 mA to 100 mA. If a step-out occurs when the seek direction is large torque, the drive current of the spindle motor (SPM) 12 is set to 80 mA (fourth rotational drive current) when the seek direction is large torque. The seek current is set to increase to 170 mA (third movement drive current). Further, when the seek direction is a direction in which the torque is small, the drive current of the spindle motor (SPM) 12 is set to 100 mA and the seek current is set to 100 mA. When the seek direction is small torque and no step-out has occurred, the seek current is further reduced from 100 mA to 80 mA, and the difference of 20 mA is distributed to the drive current of the spindle motor (SPM) 12 and increased to 120 mA. May be.

  A seek operation is performed with the set value set in this manner, and it is determined whether or not the seek has been completed (S210). If a step-out occurs during the seek operation (S211), the step-out history is updated (S212). When the step-out history is updated, it is determined that there is an update in S202 described above, and the set value is changed again according to the updated new step-out history (S204).

  Step-out can occur when the required torque is large. As described above, by increasing the drive current in the seek direction where the step-out occurs according to the step-out history, it is possible to suppress the subsequent step-out occurrence. This may be effective when the optical disk device is arranged in the vertical direction and stepping out easily occurs when the seek direction is vertically upward.

  In the present embodiment, the seek current and the drive current of the spindle motor (SPM) 12 are adjusted in accordance with the seek direction. However, the seek current upper limit value and the drive current of the spindle motor (SPM) 12 are adjusted according to the seek direction. The upper limit value of each may be adjusted up or down. Specifically, if the upper limit value of the drive current of the spindle motor (SPM) 12 when there is no seek operation is 250 mA, the drive current of the spindle motor (SPM) 12 is increased when the seek direction is the direction of large torque. The upper limit value is decreased from 250 mA to 100 mA, and the upper limit value of the seek current is set to 150 mA. When the seek direction is a direction with a small torque, the upper limit value of the drive current of the spindle motor (SPM) 12 is decreased from 250 mA to 100 mA, and the upper limit value of the seek current is decreased from 150 mA to 100 mA. Alternatively, as a second setting method, when the seek direction is a direction in which the torque is small, the upper limit value of the drive current of the spindle motor (SPM) 12 is decreased from 250 mA to 150 mA, and the upper limit value of the seek current is increased from 150 mA. Reduce to 100 mA.

  In the present embodiment, the seek structure shown in FIGS. 2 to 4 has been illustrated, but it goes without saying that the present invention is not limited to this, and is applicable to any structure in which the required torque can be changed depending on the seek direction. it can.

  Furthermore, in the present embodiment, the optical disk apparatus connected to the host by USB is exemplified, but the present invention is not limited to this, and can be applied to any optical disk apparatus in which the upper limit value of drive current or current consumption is limited. .

  10 optical disk, 12 spindle motor (SPM), 16 optical pickup, 18 thread motor, 32 system controller, 50 optical head, 60 lead screw, 61 stepping motor, 66 movable plate, 72 teeth.

Claims (5)

An optical disc apparatus for recording or reproducing data on an optical disc,
Rotation driving means for rotating the optical disk;
Movement drive means for moving and driving the optical pickup along the radial direction of the optical disc;
When the movement driving unit is not driving the optical pickup, the rotation driving unit rotates the optical disc with a first rotation driving current, and the movement driving unit drives the optical pickup in the first direction. In this case, the rotational drive current of the rotational drive means is reduced to a second rotational drive current smaller than the first rotational drive current, and the travel drive current of the travel drive means is set as the first travel drive current, and the movement When the driving means drives the optical pickup in a second direction opposite to the first direction and having a required driving torque smaller than the first direction, the rotational driving current of the rotational driving means is changed to the first direction. Control means for setting the rotation driving current of the second movement driving current of the movement driving means to be a second movement driving current smaller than the first movement driving current;
An optical disc apparatus comprising: The apparatus of claim 1.
The control means is configured to increase the rotation drive current of the rotation drive means larger than the second rotation drive current when the movement drive means drives the optical pickup in the second direction. An optical disc apparatus characterized in that the third rotational drive current is smaller than that and the travel drive current of the travel drive means is the second travel drive current. The apparatus of claim 2.
The third rotation drive current is obtained by adding a difference amount between the first movement drive current and the second movement drive current to the second rotation drive current. . In any one of Claims 1-3, Furthermore,
Step-out detection means for detecting step-out of the movement drive means,
The control means, when the step-out detecting means detects the step-out, the first movement drive current, the second movement drive current, the second rotation drive current, and the third rotation An optical disc apparatus characterized by changing at least one of drive currents. The apparatus of claim 4.
When the movement driving unit drives the optical pickup in the first direction and the step-out detecting unit detects the step-out, the control unit detects the rotation driving current of the rotation driving unit. An optical disc apparatus characterized in that a fourth rotational drive current smaller than the second rotational drive current is set to be a third rotational drive current larger than the first movable drive current. .

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