JPH0115945B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a disk recording system in which information recorded on a disk is read by rotating a disk on which information is recorded and moving a reading means for reading this information in the radial direction of the disk. This relates to a media reproducing device, in which a disc recording medium is rotated, which constitutes an information track by partial depressions on its surface, a reading beam generated from a light source is emitted onto the information track, and the reflected light modulated by the information track is emitted. Be able to receive the beam,
It is conceivable that the present invention be used in an optical digital audio disc playback device that reads information on the information track or a video disc player having almost the same configuration as above. In addition, it can also be used in recording and reproducing devices such as floppy disks, in which information is recorded and reproduced using a magnetic head by rotating a magnetic sheet.

Conventional Structure and Problems Conventionally, a method using a feed groove has been used to move a reading means for reading information recorded on a disc.

FIG. 1 shows such a conventional disk-shaped recording medium reproducing device. In FIG. 1, 1 is a magnetic recording/reproducing sheet, 2 is a drive spindle for the same sheet, 3 is a drive motor, 4 is a magnetic head for reading signals recorded on the sheet 1, and 5 is a holder for holding the magnetic head. Bearings 6a and 6b are provided at one end, and the bearings 6a and 6b are fitted onto a guide shaft 7 which is secured to a base 17 by tightening a fixing plate 18 with screws 11. A feed screw 8 is provided at the other end of the holding base 5 approximately parallel to the shaft 7, and a pin 9 that engages with the thread groove of the feed screw is fixed to a leaf spring 10, and this leaf spring 10 is held. It is fixed to the stand 5 with screws 11. Bearings 12a and 12b that hold the feed screw 8 are provided on the base 17. 13 is a thrust leaf spring that urges the feed screw in the axial direction; 14 is a retaining ring; and 15 is a feed motor, which is integrated with the feed screw via a coupling joint 16.

With the above structure, when the feed motor 15 is driven and the feed screw 8 is rotated, the holding base 5 is moved to the guide shaft 7 by the engagement of the screw groove and the pin 9.
The magnetic sheet 1 can be moved along the guide shaft 7 around the fitting portion thereof, and the information on the magnetic sheet 1 can be sequentially read by the magnetic head 4.

However, in such a conventional configuration,
Drive part (feed screw 8 side) and sliding part (shaft 7)
Since there is a large distance between the bearings 6a and 6, when the holding table 5 is driven in the direction of arrow A as shown in FIG.
A force in the B direction acts on b. This force is applied to bearing 6
Since high pressure is applied to parts of the ends of bearings 6a and 6b,
This accelerates the wear of parts a and 6b and causes vibrations during operation. Furthermore, since the frictional force between the shaft 7 and the bearings 6a and 6b increases, it is necessary to increase the size of the feed motor 15, which results in an increase in power consumption, which reduces the size and weight of the equipment.
There are drawbacks that hinder cost reduction. Further, the leaf spring 10 to which the pin 9 that engages with the thread groove of the feed screw 8 is fixed is easily bent in both the axial and radial directions of the feed screw 8, and especially when the load during movement increases as described above, the plate spring 10 is easily bent. Therefore, only the pin 9 that engages with the screw groove moves along the screw groove of the feed screw 8 due to the deflection of the leaf spring 10, resulting in a disadvantage that the accuracy of feeding deteriorates. In addition, since the outer diameter of the feed screw 8 becomes thinner at the part where the bearing 12b is fitted, the feed screw 8 can be installed and removed from the base 17 in one direction, which limits the assembly procedure. 8 and connecting joint 16
After incorporating it, it will be attached to the base. Therefore, when installing the feed motor 15 on the base, the bearing 12
a, 12b and the feed screw 8 as the reference for positioning, so when installing the feed screw 8.
The disadvantage is that the axis tends to be misaligned.

OBJECTS OF THE INVENTION The present invention solves these conventional drawbacks, and provides a disk-shaped recording medium reproducing device that has less wear on bearings and does not generate vibrations during operation.

Structure of the Invention The present invention is configured such that a moving base is attached to the feed shaft via a bearing, and the moving base moves smoothly along the outer periphery of the feed shaft via the bearing when the feed shaft rotates. This reduces vibration during operation and reduces bearing wear.

DESCRIPTION OF EMBODIMENTS Hereinafter, one embodiment of the present invention will be explained as shown in FIGS. 2 and 3.
This will be explained with reference to FIGS. 4 and 5.

In FIGS. 2 to 5, parts having the same functions as those in FIG. 1 are denoted by the same reference numerals, and explanations thereof will be omitted.
Reference numeral 19 indicates a recorded disc-shaped recording medium (hereinafter referred to as a disk) having a central hole and a partial depression on the surface forming an information track; 20 indicates the disk 1;
The turntable engages with the center hole of 9 and holds the disk 19, and the center hole is connected to the drive spindle 2.
1 and tighten the set screw 22 to the spindle 21.
is connected to. 23 is a drive motor that drives the spindle 21. The spindle 2
Reference numeral 1 denotes a component of the drive motor 23, which is composed of a motor shaft of the motor 23, and is configured in a so-called direct drive system in which the driving force of the motor 23 is directly used to drive the rotation of the disk 19. . Reference numeral 24 denotes an optical pickup, which includes an optical section 24a consisting of a light source, a photodetector, a polarizing prism, etc., and a focusing device for making the objective lens 24b follow the track vibration caused by the surface vibration or eccentricity of the disk 19. 24c, and is attached to the moving table 25. Mobile table 25
has a through hole 25a at one end, and a pair of bearings 26, 27 at both ends of the through hole 25a.
A feed member 28 that engages with a spiral groove 29a of the feed shaft 29 is provided between 6 and 27. Reference numeral 32 denotes a movable guide whose elongated hole 32a is loosely fitted into the guide shaft 31 with a sufficient gap, and which slides on the guide shaft 31, and is fixed to one end of the movable table 25 with a screw (not shown). This restricts the movement of the movable table 25 in the thickness direction of the disk 19. The feed shaft 29 has a trapezoidal screw groove 2 on a part of its outer circumference.
9a is provided, and the outer diameter of this groove 29a is the same as that of the groove 29a.
It is coaxial and finished with the same dimensions as the outer diameter of the other parts. The feed shaft 29 passes through a pair of bearings 33 and 34 provided on a base 30 and is rotatably held, and one end surface is finished into a spherical shape and supported by a thrust bearing 35. The spherical end surface of the feed shaft 29 is pressed against the thrust bearing 35 by a thrust spring 36 provided between the base 30 and the thrust bearing 35 . 37 is Tairawasiya,
38 is a retaining ring that holds the slide spring 36 and flat washer 37. The feeding member 28 includes a pedestal 28a whose outer periphery is threaded, and the pedestal 28a.
The feed pin 28b is slidably inserted into the hole of
, a compression spring 28c that presses the feed pin 28b toward the groove 29a of the feed shaft 29, and a holding plate 28d that maintains the fitted state between the feed pin 28b and the pedestal 28a. Bearing 2
The pedestal 28a is screwed and fixed at a position between 6 and 27. The holding plate 28d is attached to the base 2
A part of 8a is fixed by caulking.

With this configuration, the optical pickup can be moved using the outer periphery of the feed shaft 29, which is the drive section, as a sliding reference surface, so the bearings 26 and 27 can be moved along the feed shaft 29.
9 can be eliminated, and as a result,
There is little wear on the bearings 26, 27, and smooth movement without vibration is realized.

In addition, for the same reason, the load applied to the feed motor 15 is reduced and stabilized, making it easier to select a motor, reducing the size and power consumption, and promoting the miniaturization and weight reduction of the entire device. .

Furthermore, by fitting the feed pin 28b into the hole of the pedestal 28a and slidingly holding it there, the engagement with the groove 29a of the feed shaft 29 can be maintained in a constant state and with high precision regardless of the direction of the load. Can be done. Furthermore, if the compression spring 28c is used to press the feed pin 28b against the groove 29a of the feed shaft 29, stable pressure with less variation can be achieved compared to the conventional plate spring 10.

Furthermore, since the axial load of the feed shaft 29 is received by the spherical end surface, wear at this receiving portion is also minimized. In addition, since the outer diameter of the feed shaft 29 is configured to be the same throughout the entire axial direction, the feed motor 1
5 can be mounted on the base 30 with the front facing forward, and in this case, the bearings 33 and 34 of the base 30 can be used as positioning references, so that the axes of the feed motor 15 and the feed shaft 29 can be aligned with high precision. This makes it easy to prevent the motor shaft from twisting due to misalignment. Furthermore, by providing the thrust spring 36 between the base and the thrust bearing 35, the feed shaft 29 can be attached and removed simply by removing the thrust bearing 35.
6. The work can be carried out with the flat washer 37 and retaining ring 38 attached to the feed shaft 29, making the work easier. Also, by engaging the thrust spring 36 with the thrust bearing 35 and positioning the thrust spring 36, the thrust spring 36 is moved to the feed shaft 29.
The feed shaft 29 can be biased in the axial direction without contacting the feed shaft 29.

In the above embodiment, the holding means for the feed pin 28b was constructed by fixing the holding plate 28d to the pedestal 28a. It is also possible to have a configuration in which it is held only by the user.

Effect of the invention According to the invention, (1) Bearing wear on the moving platform can be reduced.

(2) Smooth operation is achieved because prying is prevented when moving the moving table.

(3) The feed motor can be easily selected, and it can be made smaller, lighter, and consume less power.

(4) It is easy to assemble the feed motor and allows for highly accurate positioning.

(5) The feed shaft can be easily installed and removed.

This excellent effect can be obtained.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a conventional example, FIG. 2 is a perspective view showing an embodiment of the present invention, FIG. 3 is a plan view of the above embodiment, FIG. 4 is a side view of the above embodiment, and FIG. The figure is a partially enlarged sectional view of the above embodiment. 1...Magnetic sheet, 6a, 6b, 12a, 12
b...Bearing, 4...Magnetic head, 5...Holding stand,
7...Guide shaft, 8...Feed screw, 11...Screw, 15...Feed motor, 16...Connection joint, 1
7...Base, 18...Fixing plate, 19...Disc (disk-shaped recording medium), 20...Turntable, 2
3... Drive motor, 24... Optical pickup, 25... Moving table, 26, 27... Second bearing, 33, 34... First bearing, 28... Feeding member, 29... Feeding shaft , 30... Base, 31... Guide shaft, 32... Movement guide, 35... Thrust bearing, 36... Thrust spring.

Claims (1)

[Scope of Claims] 1. A reading means for reading information on a disk provided with an information track, a base having a pair of first bearings, and a base having a pair of first bearings, and a means for penetrating the first bearing of the base and being rotatably held. , a feed shaft having a continuous spiral groove formed in a part of its outer periphery, a biasing means for biasing the feed shaft in the axial direction, and a feed shaft biased by the biasing means. a holding means for holding the end face; a guide shaft disposed substantially parallel to the feed shaft and fixed to the base; a moving guide that moves along the guide shaft; a movable base that is rotatably mounted relative to the feed shaft via a second bearing and partially includes the movement guide and reading means; and the pair of second bearings of the movable base. a feed member provided between the feed shaft and the feed member that engages with the groove of the feed shaft and sends the movable base in the axial direction of the feed shaft in accordance with rotation of the feed shaft; The outer periphery that fits into the first bearing and the second bearing of the movable table are set to have the same outer diameter dimension, and one end face is configured in a spherical shape, and the biasing means is connected to the base and the holding means. 1. A disk-shaped recording medium reproducing device characterized in that an engaging means is provided between the holding means and engages with a part of the urging means. 2. The feed member includes a feed pin that engages with a groove in the feed shaft, a pedestal that has a fitting portion that slides the feed pin in the radial direction of the feed shaft, and a feed pin between the pedestal and the feed pin. 2. The disk-shaped recording medium reproducing device according to claim 1, further comprising a compression spring that presses the feed shaft toward the groove, and a holding means that holds the feed pin on the base.