JP3683056B2 - Optical pickup feeding rack - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical pickup feeding rack constituting an optical pickup feeding mechanism for moving an optical pickup in a radial direction of a disk in a recording / reproducing apparatus for recording or reproducing information on a disk-shaped recording medium (hereinafter referred to as “disk”). About.
[0002]
[Prior art]
FIG. 11 is a perspective view showing a conventional optical pickup feeding mechanism disclosed in, for example, Japanese Patent Laid-Open No. 4-298866, FIG. 12 is a side view showing the configuration of the rack, and FIG. 13 is an exploded perspective view of the rack.
[0003]
In the figure, a disk 5 is placed on a turntable 1 and is rotationally driven by a driving force of a spindle motor 2. The optical pickup 3 is mounted on and fixed to the pickup support 4 and includes an objective lens 3a. A rack 100 is attached to the pickup support base 4 with screws 30. The rack 100 is supported by a leaf spring 15 having an attachment portion 15 a attached to the pickup support base 4 and one end thereof and always meshes with the screw shaft 6. The rack base 13 includes a first rack 11 having one tooth 11a and a second rack 12 having second teeth 12a that mesh with the screw shaft 6 when an impact is applied. When the screw shaft 6 rotates, the pickup support 4 moves in the radial direction of the disk 5 via the rack 100 so that the signal on the recording surface of the disk 5 rotated by the spindle motor 2 is read by the optical pickup. It is configured.
[0004]
[Problems to be solved by the invention]
The conventional rack 100 configured as described above includes the attachment portion 15a of the leaf spring 15 of the first rack 11 having the first teeth 11a and the second rack 12 having the second teeth 12a. Since the rack base 13 is structured to be fastened to the pickup support 4 with screws 30, the assemblability is poor, and the second rack 12 is arranged in the axial direction of the screw shaft 6 as shown in FIG. Since it is formed in a straight tooth shape in a direction perpendicular to the rack 100, when an impact in the radial direction of the disk 5 (axial direction of the screw shaft 6) is applied to the rack 100, the second teeth 12a of the second tooth 12a as shown in FIG. There is a problem that it is easy to break because it receives a force at a certain point, and the cost is high due to the large number of parts.
[0005]
The present invention has been made to solve the above-described problems. An object of the present invention is to provide a rack having a novel structure in an optical pickup feeding mechanism and to solve the above-described problems.
[0006]
[Means for Solving the Problems]
An optical pickup feeding rack according to the present invention is a rack having teeth engaged with a screw shaft rotated by a drive motor , and feeding an optical pickup attached to a pickup support base in a radial direction of a disk, provided on the rack, a first tooth sending the optical pickup in a radial direction of the disk by meshing always the screw shaft, a second tooth meshing with the screw shaft when the shock is applied, the pickup A leaf spring attached to a support base and biasing the rack to press the first teeth and the second teeth against the screw shaft; and the first teeth and the second teeth; and the plate spring is integrally formed with, said first tooth is formed on a straight-toothed, said second tooth impact is added The the above first tooth when it is characterized in that it is formed in an arc shape along the thread groove of the screw shaft so as to mesh with the screw shaft from different directions.
[0008]
Further, a reinforcing part formed by insert molding of synthetic resin is provided on an attaching part formed by a leaf spring of a rack attached to the pickup support base.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
In the rack according to the embodiment of the present invention, since the first teeth are always meshed with the screw shaft by the elastic force of the leaf spring, the load fluctuation factor due to the vibration of the screw shaft is absorbed, and stable feed characteristics are obtained. Is obtained.
In addition, when an impact is applied in the axial direction of the screw shaft, the first teeth are pushed against the tooth surface of the screw shaft and escape in the radial direction, but the second teeth mesh with the screw shaft to prevent the runaway of the pickup. .
In addition, since the first teeth and the second teeth are integrally formed, the accuracy of the dimensions of the first teeth and the second teeth can be easily ensured with the molding accuracy, and the leaf spring is also provided. Since they are integrally formed, the number of parts is reduced.
[0010]
In addition, since the second tooth is formed in an arc shape along the screw groove of the screw shaft, the second tooth comes into surface contact with the screw groove of the screw shaft when an impact is applied to the second tooth. Since the applied force works to be dispersed, the impact resistance of the second tooth is improved.
[0011]
Furthermore, since the mounting part formed by the leaf spring of the rack that is attached to the pickup support base is provided with a reinforcement part that is insert-molded with synthetic resin, the rigidity of the mounting part is increased and the axial force of the screw shaft is increased. On the other hand, since it works to suppress the torsional deformation of the mounting portion, the number of mounting screws can be reduced.
[0012]
Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
Embodiment 1 FIG.
FIG. 1 is a perspective view showing an optical pickup feeding mechanism according to Embodiment 1 of the present invention. 1 is a turntable, 2 is a spindle motor, 3 is an optical pickup, and 4 is mounted and fixed on the optical pickup 3. A pickup support 5 is a disk, and 6 is a screw shaft.
[0013]
FIG. 2 is a plan view showing a configuration of the rack 10 and the screw shaft 6 according to the first embodiment, a front view, and a three-view view showing a side view. In the figure, reference numeral 15 denotes a leaf spring for absorbing the factor of load fluctuation, and an attachment portion 15a for attachment to the pickup support 4 is provided. 21 is a first tooth that always meshes with the screw shaft 6, 22 is a second tooth, which is formed in a direction contacting the screw shaft 6 from a direction different from the first tooth, and when the rack 10 is subjected to an impact, It is configured to mesh with the screw shaft 6. The first teeth 21 and the second teeth 22 are formed of a synthetic resin integrally molded product, and the leaf spring 15, the first teeth 21 and the second teeth 22 are integrally formed by insert molding to form the rack 10. Is configured.
[0014]
FIG. 3 is an exploded perspective view of the rack 10 according to the first embodiment, and 30 is a screw for attaching the rack 10 to the pickup support 4.
FIG. 4 is a diagram for explaining the operation of the rack 10 when an impact in the radial direction of the disk is applied to the rack.
[0015]
In the optical pickup feeding mechanism configured as described above, the first teeth 21 of the rack 10 are always meshed with the screw shaft 6 by the elastic force of the leaf spring 15, while the second teeth 22 are normally 0. The clearance of about 1 mm is maintained and it does not mesh with the screw shaft 6, and the impact in the radial direction of the disk (the axial direction of the clew shaft 6) is applied to the rack 10, so that the first teeth 21 are thread grooves of the screw shaft 6. When it is pushed by one side and escapes, it moves in the axial direction of the screw shaft 6 so as to engage with each other.
[0016]
In the rack 10 according to the first embodiment, the first teeth 21 are always meshed with the screw shaft 6 due to the elastic force of the leaf spring 15, so that the first teeth 21 are smooth even if the screw shaft 6 is swung. Stable feed characteristics can be obtained by absorbing load fluctuations.
[0017]
Further, when an impact in the axial direction B of the screw shaft 6 is applied to the rack 10, the second teeth 22 are pushed against one surface of the thread groove 6 a as shown in FIG. In order to escape in the direction, as shown in FIG. 4, the leaf spring 15 is deformed with the end E of the screw head of the screw 30 as a fulcrum, and the second teeth 22 formed integrally with the first teeth 21 are screw shafts. 6 moves in the axial direction of the shaft 6 and meshes with the screw shaft 6, so that a stable feed characteristic can be secured and the runaway of the pickup can be prevented.
[0018]
Further, the rack 10 has the first teeth 21 and the second teeth 22 integrally formed of synthetic resin, so that the dimensional accuracy of the first teeth 21 and the second teeth 22 can be ensured, and the plate 10 Since the spring 15 is also integrally formed by insert molding, the number of parts is reduced and the assembly workability is improved.
[0019]
Embodiment 2. FIG.
FIG. 5 is a perspective view showing the rack 10 according to the second embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 3 denote the same or corresponding parts, respectively, 33 is a second tooth formed at a position facing the first tooth 21 and sandwiching the screw shaft 6, and the tooth profile is the screw shaft. It is formed in a circular arc shape along the six screw grooves 6a.
[0020]
FIG. 6 illustrates an operation when an impact in the axial direction (direction of arrow B) of the screw shaft 6 is applied to the rack 100 in the pickup feeding mechanism using the rack 100 of the conventional example shown in FIGS. It is the figure which showed the positional relationship of the 2nd rack 12 and the screw shaft 6. FIG.
[0021]
FIG. 7 is a second diagram for explaining the action when an impact in the axial direction (direction of arrow B) of the screw shaft 6 is applied to the rack 10 in the pickup feeding mechanism using the rack 10 of the second embodiment. It is a figure which shows the positional relationship of the tooth | gear 33 and the screw shaft 6. FIG.
[0022]
In FIG. 6, the conventional rack 100 is provided with straight tooth-like second teeth 12 a as shown in FIGS. 6A and 6B, so that an impact in the direction of arrow B is applied to the rack 100. The second tooth 12a moves from the stable position in the direction of arrow B as shown in FIG. 6 (a), and the second tooth 12a hits one side of the screw groove 6a of the screw shaft 6 at the C portion. May concentrate and the second tooth 12a may be damaged.
[0023]
In contrast, the second teeth 33 of the second embodiment are formed in an arc shape along the thread groove 6a of the screw shaft 6 as shown in FIGS. 7A and 7B. When the impact in the direction of the arrow B is applied to 10, the second tooth 33 moves in the B direction, but the surface does not concentrate on one point by hitting the slanted one side D of the screw groove 6a of the screw shaft 6 and Less damage.
[0024]
FIG. 8 is a diagram showing the impact resistance of the conventional rack 100 and the rack 10 of the second embodiment, and the second teeth are damaged by applying an axial impact of the screw shaft 6 to the racks 100 and 10. The value of the impact force G is shown. As is clear from this figure, the second tooth 33 of the second embodiment is less likely to be damaged than the second tooth 12a of the conventional example, and can withstand a greater impact force.
[0025]
Embodiment 3 FIG.
FIG. 9 is a perspective view showing a method of attaching the rack 10 of the first and second embodiments to the pickup support base 4. In the figure, 31 is a through hole formed in the attachment portion 15 a of the leaf spring 15 and is attached to the pickup support 4 with two screws 30.
[0026]
FIG. 10 is a perspective view showing a rack 10 according to the third embodiment of the present invention. In the figure, reference numeral 34 denotes a reinforcing portion in which synthetic resin is insert-molded in the mounting portion 15a of the leaf spring 15. By providing this reinforcing portion 34, the rigidity of the mounting portion 15a is increased.
In the flat sheet metal mounting portion 15a shown in FIG. 9, both ends of the mounting portion 15a are suppressed in order to prevent the mounting portion 15a from being twisted and deformed by an impact force when an axial impact of the screw shaft 6 is applied to the rack 10. The through holes 31 are provided at two places and fixed with two screws 30. However, in the third embodiment, the mounting portion 15a of the leaf spring 15 is increased in rigidity by the insert-molded synthetic resin so that it is difficult to twist. Therefore, it can be attached with one same 30 and the number of parts can be reduced.
[0027]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
[0028]
The rack for feeding an optical pickup according to the present invention includes a first tooth that is always meshed with the screw shaft and a direction that comes into contact with the screw shaft from a direction different from the first tooth. Since the second teeth meshing with each other are integrally formed, variations in the mechanical accuracy of the first teeth and the second teeth are unlikely to occur, and the first teeth and the second teeth are attached to a pickup support base. Since the leaf spring that urges the teeth to press against the screw shaft is also integrally formed, the number of parts can be reduced and the cost can be reduced. Further, since the second tooth is formed in an arc shape along the screw groove of the screw shaft, the second tooth and the screw groove of the screw shaft are in surface contact, and the impact resistance of the second tooth is improved.
[0030]
In addition , the mounting part formed by the leaf spring of the rack attached to the pickup support base is provided with a reinforcement part made by insert molding synthetic resin to increase the rigidity of the mounting part, so the number of mounting screws is reduced. Cost reduction can be achieved.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an optical pickup feeding mechanism according to Embodiment 1 of the present invention.
FIG. 2 is a three-side view illustrating the configuration of a rack and a screw shaft according to the first embodiment.
FIG. 3 is an exploded perspective view of a rack according to the first embodiment.
FIG. 4 is a diagram illustrating the movement of the rack when an axial impact is applied to the rack according to the first embodiment.
FIG. 5 is a perspective view showing a rack according to Embodiment 2 of the present invention.
FIG. 6 is a diagram for explaining an operation when an impact is applied to a rack of a conventional example.
FIG. 7 is a diagram for explaining an action when an impact is applied to the rack according to the second embodiment.
FIG. 8 is a diagram showing impact resistance of a conventional rack and a rack according to the second embodiment.
FIG. 9 is a perspective view showing a rack mounting structure according to the first and second embodiments.
FIG. 10 is a perspective view showing a rack according to Embodiment 3 of the present invention.
FIG. 11 is a perspective view showing a conventional optical pickup feeding mechanism.
FIG. 12 is a diagram showing a configuration of a rack of a conventional example.
FIG. 13 is an exploded perspective view of a conventional rack.
[Explanation of symbols]
1 Turntable, 2 Spindle motor, 3 Optical pickup,
3a objective lens, 4 pickup support base, 5 disc, 6 screw shaft, 10 rack, 15 leaf spring, 15a mounting portion, 21 first tooth,
22, 33 2nd tooth, 31 through-hole, 34 reinforcement part.

Claims (2)

A rack having teeth engaged with a screw shaft rotated by a drive motor, and sending an optical pickup attached to a pickup support base in a radial direction of the disk,
A first tooth provided on the rack and constantly feeding the optical pickup in the radial direction of the disk by meshing with the screw shaft ;
A second tooth meshing with the screw shaft when the shock is applied,
A leaf spring attached to the pickup support, for biasing the rack and pressing the first teeth and the second teeth against the screw shaft;
The first tooth, the second tooth, and the leaf spring are integrally formed,
The screw teeth of the screw shaft are formed so that the first teeth are formed in a straight tooth shape, and the second teeth mesh with the screw shaft from a direction different from the first teeth when an impact is applied. An optical pickup feeding rack characterized by being formed in an arc shape along a groove.   2. The rack for feeding optical pickup according to claim 1, wherein a reinforcing portion formed by insert molding of synthetic resin is provided in an attachment portion formed by a leaf spring of a rack attached to the pickup support base.

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