JP3889489B2 - Information processing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an information processing apparatus applied as, for example, an optical disc apparatus.
[0002]
[Prior art]
The optical disk apparatus includes a pickup (optical head), and the pickup is caused to travel in the radial direction of the optical disk along the guide shaft by a driving force of a linear motor (drive circuit) to scan light. On the other hand, data is recorded or reproduced.
[0003]
By the way, it is necessary to make the center of thrust and the center of gravity coincide with each other so that an unnecessary vibration component is not generated in the pickup during traveling of the pickup.
Two methods are conceivable as a method of matching the center of thrust and the center of gravity.
[0004]
One is a method in which a linear motor is arranged in accordance with the position of the center of gravity of the pickup, and the other is a method in which the linear motor is fixed and a counterweight is added to the pickup.
[0005]
[Problems to be solved by the invention]
However, when the linear motor is arranged in accordance with the center of gravity of the pickup, there is a problem that the linear motor cannot be arranged at a desired position because the position of the linear motor is determined by the center of gravity of the pickup.
[0006]
For example, when considering a thin drive, it is disadvantageous because the vertical dimension is restricted by the position of the center of gravity of the pickup.
In other words, the thickness of the drive base or the space in which the IC is placed is restricted and becomes a bottleneck for thinning.
[0007]
On the other hand, the method of adding a counterweight is equivalent to adding useless mass to the pickup, leading to a decrease in access sensitivity and an increase in the number of parts, leading to an increase in cost.
[0008]
The present invention has been made in view of the above circumstances, and can determine the arrangement position of the driving means without being restricted by the position of the center of gravity of the optical head, and the center of the thrust without adding a counterweight to the optical head. An object of the present invention is to provide an information processing apparatus that can match the center of gravity with the center of gravity.
[0012]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides an information processing apparatus according to claim 1 , wherein an optical head that irradiates light onto an optical disk, and the optical heads disposed on both sides of the optical head are guided in the radial direction of the optical disk A pair of guide shafts, an electromagnetic coil that is attached to the optical head and is slidable along the guide shaft together with the optical head, and the guide shaft is centered outside the guide shaft a yoke which is rotatably disposed, the opposite to the guide shaft and the electromagnetic coil and a magnet that is provided integrally with the yoke, the yoke is freely rotates about the guide shaft By disposing the optical head generated by the electromagnetic coil, yoke and magnet, Wherein the force center is configured to be able to match the center of gravity of the optical head.
[0016]
In the present invention, the driving means is rotated around the guide means (guide shaft) to displace the center of thrust of the optical head so as to coincide with the center of gravity of the optical head without being restricted by the position of the center of gravity of the optical head. Can be placed.
Further, the center of thrust of the optical head and the center of gravity can be matched without using unnecessary parts such as a counterweight.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below with reference to an embodiment shown in the drawings.
FIG. 2 shows a separation optical system type optical disk apparatus. In FIG. 2, reference numeral 1 denotes a spindle motor which rotates while supporting a disk D as a medium.
[0018]
A movable optical head 2 is opposed to the disk D. The optical head 2 is reciprocated along the radial direction of the disk D by a drive magnetic circuit 3 as drive means described later. An introduction port 16 for introducing a laser beam is provided in the front portion of the optical head 2. Inside the optical head 2 is provided a rising mirror 4 for raising the laser beam R, and an objective lens 5 for condensing the laser beam R on the disk D is provided on the upper surface portion.
[0019]
Further, a fixed optical unit 6 that oscillates the laser beam R on the optical head 2 is provided on an extension line of the optical head 2 in the traveling direction. In the fixed optical unit 6, a semiconductor laser 7 that oscillates the laser beam R, a collimator lens 8 that collimates the laser beam R, and an anamorphic prism 9 that shapes the beam into a circle are disposed.
[0020]
The laser beam R oscillated from the semiconductor laser 7 is sent to the optical head 2 through the collimating lens 8 and the anamorphic prism 9, and enters the inside through the laser introduction port 16, and then is raised by the raising mirror 4 to be disc. D is irradiated and information is read or written.
[0021]
FIG. 1 is a perspective view showing a drive magnetic circuit 3 for running the optical head 2.
The optical head 2 is mounted on a carriage 10, and the carriage 10 is guided along the radial direction of the disk D by guide shafts 11a and 11b serving as guide means also serving as a second yoke. On both sides of the carriage 10, linear motor coils 13a and 13b are disposed as electromagnetic coils through which the guide shafts 11a and 11b are slidably inserted. Linear motor yokes 14 and 14 as first yokes are disposed on the outer portions of the guide shafts 11a and 11b. Linear motor yokes 14 and 14 are integrally provided with linear motor magnets (hereinafter simply referred to as “magnets”) 15, and these magnets 15 and 15 are opposed to the guide shafts 11a and 11b and the linear motor coils 13a and 13b. Yes.
[0022]
When electric current is passed through the linear motor coils 13a and 13b, electromagnetic force is generated, and the carriage 10 travels along the guide shafts 11a and 11b. By this running, the laser beam R irradiated from the objective lens 5 of the optical head 2 is scanned in the disk D.
[0023]
FIG. 3 is a diagram showing the apparatus main body 21 of the optical disc apparatus and the drive magnetic circuit 3 of the optical head 2 provided in the apparatus main body 21.
The apparatus main body 21 includes a substrate 22 and a drive base 23 that faces the substrate 22 in a spaced manner. The drive magnetic circuits 3 and 3 are disposed between the substrate 22 and the drive base 23, and the yokes 14 and 14 constituting the drive magnetic circuits 3 and 3 are rotatably disposed around the guide shafts 11a and 11b. ing. The wall thickness of the drive base 23 is inclined corresponding to the rotation angle of the yokes 14, 14, and the wall thickness gradually increases toward the rotation center of the yokes 14, 14.
[0024]
By the way, when the optical head 2 is traveling, in order not to generate an unnecessary vibration component in the optical head 2, it is necessary to match the center of thrust with the center of gravity. In this case, the thrust center position is determined by the positional relationship between the magnets 15 and 15 of the drive magnetic circuit 3 and the linear motor coils 13a and 13b.
[0025]
Next, a method for matching the center of thrust of the optical head 2 with the center of gravity will be described.
FIG. 3 shows an example in which the center of gravity position b is above the thrust center a of the optical head 2.
[0026]
In this case, the out yokes 14 and 14 and the magnets 15 and 15 of the drive magnetic circuits 3 and 3 are rotated around the guide shafts 11a and 11b in the direction of the arrow as shown in the figure. As a result, the thrust center a moves to the center of gravity position b and matches.
[0027]
When the center of gravity is located below the thrust center of the optical head 2, the out yokes 14 and 14 and the magnets 15 and 15 of the drive magnetic circuits 3 and 3 are centered on the guide shafts 11a and 11b. Rotate in the opposite direction of the arrow. Thereby, the thrust center moves downward and coincides with the center of gravity.
[0028]
Even if the position of the center of gravity varies from product to product due to component variations, if the amount of rotation of the out yokes 14 and 14 and the magnets 15 and 15 is designed in consideration of them, correction is made with a spacer such as aluminum foil. Is possible.
[0029]
As described above, since the out yokes 14 and 14 and the magnets 15 and 15 of the drive magnetic circuits 3 and 3 are rotated about the guide shafts 11a and 11b to move the center of thrust to coincide with the center of gravity, In addition, it is not necessary to reduce the thickness of the base 23 when the center of gravity is located on the upper side, and the rigidity can be maintained, and when the center of gravity is located on the lower side, the space area where the IC or the like is disposed is not reduced, This is advantageous for making the apparatus main body 21 thinner.
[0030]
Furthermore, since no counterweight is added to the optical head 2, the number of parts does not increase, and adverse effects such as an increase in cost and a decrease in access sensitivity can be avoided.
[0031]
FIG. 4 shows drive magnetic circuits 31 and 31 according to another embodiment of the present invention.
In addition, about the same part in the said embodiment, the same number is attached | subjected and the description is abbreviate | omitted.
[0032]
In the above-described embodiment, the guide shafts 11a and 11b are also used as the yoke of the drive magnetic circuit 3. However, in this embodiment, the guide shafts 32 and 32 are also used as the yoke of the drive magnetic circuit 11, and the guide function is used. Is only held.
[0033]
Also in this embodiment, as shown in FIG. 5, for example, when the center of gravity position b is below the thrust center a of the optical head 2, as shown in FIG. The yokes 34 and 34 and the magnets 35 and 35 of 31 are rotated and fixed around the guide shafts 32 and 32 in the arrow direction in the figure. Thereby, the thrust center a moves to the center of gravity position b and coincides.
[0034]
【The invention's effect】
As described above, in the present invention, the driving magnetic circuit is rotated around the guide means (guide shaft) to displace the center of thrust of the optical head so as to coincide with the center of gravity. Compared with the case where the guide means and the drive magnetic circuit are moved in the vertical direction according to the position of the center of gravity of the head, a large space is not required, which is advantageous for thinning.
[0035]
Further, since no unnecessary parts such as a counterweight are required, the access sensitivity is not lowered and the cost is not increased.
Furthermore, the amount of deviation between the center of thrust and the center of gravity due to component variations can be corrected, and reliability can be improved.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an optical head and a drive system thereof according to an embodiment of the present invention.
FIG. 2 is a configuration diagram showing an optical disc apparatus.
FIG. 3 is a diagram showing an operation for making the center of thrust and the center of gravity of an optical head coincide with each other.
FIG. 4 is a perspective view showing an optical head and its drive system according to another embodiment of the present invention.
FIG. 5 is a diagram showing a state in which the center of gravity of the optical head is located on the lower side of the thrust center.
FIG. 6 is a diagram showing an operation for making the center of thrust and the center of gravity of the optical head coincide with each other.
[Explanation of symbols]
D ... Optical disc (medium)
2 ... Optical head (optical head)
11, 32 ... Guide shafts 3, 31 ... Drive electromagnetic circuit (drive means)
13 ... Electromagnetic coils 14, 34 ... Yoke 15 ... Magnet

Claims (1)

An optical head that emits light to the optical disc ;
A pair of guide shafts disposed on both sides of the optical head, for guiding the optical head in a radial direction of the optical disc ;
An electromagnetic coil attached to the optical head and inserted through the guide shaft so as to be slidable along the guide shaft together with the optical head ;
A yoke disposed outside the guide shaft so as to be rotatable around the guide shaft ;
A magnet provided integrally with the yoke, facing the guide shaft and the electromagnetic coil ;
The yoke is arranged so as to be rotatable about the guide shaft, so that the thrust center of the optical head generated by the electromagnetic coil, the yoke and the magnet can coincide with the center of gravity of the optical head. the information processing apparatus characterized by being.

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