JPH0229573Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a laser pickup moving device suitable for use in, for example, compact disc players.

BACKGROUND ART A laser pickup used in a compact disc player or the like moves along the radial direction of the disc and detects a recorded signal on the disc. Furthermore, during normal performance, the pickup is moved in small steps with a quick response, and when the beginning of a song is started, it is moved at high speed to shorten the waiting time. When moving a pick-up like this, the output from the drive motor is transmitted via the power transmission section to the pick-up moving platform on which the pick-up is mounted, and the movement of the pick-up moving platform causes the pickup to move. will be carried out. A large number of gears are used in the power transmission section that transmits the output from the drive motor to the pick-up moving table. As a result, mechanical looseness such as gear backlash and belt slipping has traditionally occurred, resulting in poor pick-up response.
Therefore, there are problems in that the desired movement may not be performed, or it may take a long time to wait for the beginning of a song, and furthermore, it requires a large amount of man-hours to set the pick-up movement speed.

Purpose The present invention solves the above-mentioned technical problems, improves the responsiveness of the laser pick-up, enables high-speed forwarding when starting a song, and furthermore allows the laser pick-up to easily set the pick-up movement speed. It is an object of the present invention to provide a pick-up mobile device.

Structure of the invention The present invention includes a power transmission section that transmits output from a drive motor, and a disk that can be moved along the radial direction by the power from the power transmission section, and that emits laser light to the disk during movement. a laser pick-up for detecting a recording signal on a disk by irradiation; In a laser pick-up moving device in which the moving speed of the pick-up is changed by changing the voltage applied to the drive motor, a gear head having a plurality of gear groups housed therein is detachably attached to the drive motor. ,
A worm is fixed to the rotating shaft of the gear head, and the backlash absorption means includes a fixed rack that meshes with a pinion rotationally driven by the worm, and a movable rack that meshes with the pinion and is movable relative to the fixed rack. , a coil spring having one end fixed to the fixed rack and the other end fixed to the movable rack, and the spring force of the coil spring causes the teeth of the pinion to be sandwiched between the fixed rack and the movable rack. This is a laser pickup moving device characterized by pressure.

Embodiment FIG. 1 is an overall perspective view of an embodiment of the present invention. A disk 1 as a recording medium is inserted through an entrance 3 into a body 2 of audio equipment or video equipment that reproduces the recorded contents of the disk 1.

2 is a simplified plan view showing the internal structure of the embodiment shown in FIG. 1, FIG. 3 is a perspective view of a part of FIG. 2, and FIG. FIG. 5 is a right side view of FIG. 2, and FIG. 6 is a rear view of FIG. 2. A pickup 4 for detecting signals recorded on the disk 1 is provided below the disk 1. The pick-up 4 is held by a holding member 5. Furthermore, this holding member 5 is fixed to a pick-up moving table 6. The pick-up moving table 6 can be displaced in the vertical direction in FIG. 2 by a pick-up moving device, which will be described later, which is disposed on the left side of the machine body 2 (see FIG. 2). An irradiation hole 7 through which a laser beam is irradiated is formed in the pickup 4, and the laser beam is irradiated toward the disk 1 from the irradiation hole 7, and a recorded signal on the disk 1 is detected.

A pick-up feeding motor 8 is provided on the left side of the pick-up 4. A gear head 10 having a plurality of gear groups 9 housed therein is attached to the end of the motor 6, as shown in FIG. This gear head 10 reduces the output rotation of the motor 8. Note that this gear head 10 is connected to the motor 8.
The amount of deceleration can be adjusted by appropriately using various gear heads.

Referring to FIG. 3, the rotating shaft 11 of the gear head 10
A worm 12 is fixed to. A screw 13 is disposed close to the end 11a of the rotating shaft 11 through which the worm 12 is inserted so as to have a common axis with the rotating shaft 11. This screw 13 is supported by the body 2 by a support member 14, and the shaft portion 15 of the screw 13
The tip 15a of the rotary shaft 11 can come into contact with the end 11a of the rotating shaft 11.

Worm foil 1 is placed on the inside of the worm 12.
6 is provided. This worm foil 16 meshes with the worm 12. A pinion 18 is formed on the upper outer periphery of the rotating shaft 17 of the worm wheel 16, and a rack portion 19 having a rack that can be engaged with the pinion 18 extends in the vertical direction in FIG. It is provided. A guide rod 20 is disposed below the rack portion 19 and is parallel to the moving direction of the pick-up 4 (vertical direction in FIG. 2).
Bearings 21 and 22 are mounted on this guide rod 20. The bearings 21 and 22 are fixed to the holding member 5.
Another guide rod 23 parallel to the guide rod 20 is arranged on the right side of the pickup 4 in FIG.
A bearing holder 24 is attached to this guide rod 23.
The bearing holder 24 is formed at the upper end of the pick-up moving table 6.

In the moving device having such a configuration, when the motor 8 is driven, rotational driving force is transmitted to the gear head 10, worm 12, worm wheel 16, and pinion 18, and the rack portion 19 is displaced in the vertical direction in FIG. do. At this time, the pick-up moving table 6, which is integrally formed with the rack portion 19, is also guided by the guide rods 20 and 23 and displaced in the vertical direction in FIG. Therefore, the laser pickup 4 also moves up and down, and at the same time as the laser pickup 4 moves, the laser beam is irradiated from the irradiation hole 7 toward the disk 1, and the recording signal of the disk 1 is detected.

FIG. 8 is a simplified cross-sectional view of the drive motor 8. FIG. This drive motor 8 is a so-called coreless motor, and has a rotating shaft 30 and a rotating shaft 3.
Permanent magnets 3 integrally provided on the left and right sides of 0
1 and 32, and a field coil 33 surrounding the permanent magnets 31 and 32. In a normal motor, an iron core around which a coil is wound is used for the field, but this motor 8 does not use an iron core.
It is only a coil. By using a coreless motor as the drive motor 8 in this way, the moment of inertia of the motor is reduced, and therefore, it is possible to quickly follow the pickup. Further, switching between minute feed and high speed pick-up is performed by switching the voltage applied to the motor 8. In this case, by using a coreless motor, the starting voltage can be reduced, and therefore a large speed ratio can be achieved during speed switching.

FIG. 9 is an enlarged perspective view of the bearing 21, and FIG.
The figure is a sectional view taken along the section line XX in FIG. 9. Balls 35 are rotatably housed in the cage 34, and the cages are successively connected to the bearing 2.
Bearing 2 from one row on the inner peripheral surface side along the longitudinal direction of Bearing 1
The other row inserted into the inside of 1 is formed into an endless ring shape. This row on the inner circumferential surface side protrudes inward from the inner circumferential surface by about 1/3. A plurality of such ball rows are arranged along the circumferential direction.

By using such a linear ball bearing, the sliding resistance with respect to the guide rod 22 is reduced, and the load on the motor 8 is reduced.

FIG. 11 is an enlarged view of the rack portion 19 and its vicinity.
The rack portion 19 consists of a fixed rack 35 that is integrally fixed to the holding member 5, a coil spring 36, and a movable rack 37. The coil spring 36 is connected at one end to a fixed rack 35 and at the other end to a movable rack 37. Therefore, the movable rack 37
is biased upward in FIG. This easy 3
5 and 37 can be engaged with the pinion 18. Therefore, the teeth 18a of the pinion 18 are connected to the rack 35,
37, which prevents gear backlash and enables rapid transmission.

Next, the moving operation of the pickup 4 will be explained. When the motor 8 is started, power is transmitted to the rack 19 via the gear head 8, worm 12, pinion 18, etc. When this rack part 19 is displaced along the moving direction A, since the rack part 19 is fixedly provided on the moving table 6, the moving table 6 and therefore the pick-up 4 are moved along the moving direction A in a small feed state. do. During the movement of the pick-up 4, when the locking portion 5a of the holding member 5 presses the origin detection switch 38 (see FIG. 2), the motor 8 is deenergized and the pick-up 4 is stopped. After that, the motor 8 is energized to rotate in reverse and at high speed,
The pick-up 4 quickly returns to its original position. Furthermore, by pressing an operation key (not shown) when finding the beginning of a song, the motor 8 rotates at high speed, which allows the pick-up 4 to be fed at high speed and reach a predetermined position in a short time. becomes. Note that switching between minute feed and high speed feed is performed by switching the voltage applied to the motor 8.

FIG. 12 is an exploded perspective view of the vicinity of the pickup 4, and FIG. 13 is an exploded perspective view of the pickup 4 as viewed from the side indicated by arrow B in FIG. The pick-up 4 is a rectangular body 40
and a protrusion 41 provided at the lower part of the rectangular body 40. A pair of left and right screw holes 42 and 43 are formed in the front surface of the rectangular body 40. A laser irradiation section 59 is provided on the upper surface of the rectangular body 40 toward the right, and a laser irradiation hole 7 through which laser is irradiated is formed in the center of the laser irradiation section 59.

A holding member 5 for holding the pick-up 4 is arranged outside the pick-up 4. This holding member 5 is formed in a substantially U-shape and includes a base portion 44 and a pair of side portions 45 and 46 perpendicular to the base portion 44 . The base 44 has a screw hole 42 for the pick-up 4,
A long hole 47 and a round hole 48 are formed corresponding to the hole 43, respectively. The elongated hole 47 extends in the width direction of the base 44 (vertical direction in FIG. 12). Guide rods 49 and 50 that are perpendicular to the side portion 45 and project outward are arranged in parallel on the side portion 45 . Axial holes 51a, 51b, and 51c are formed in the side portion 46 along the longitudinal direction. With the holding member 5 surrounding the pick-up 4, the screw 52 is inserted into the disc spring 53.
The elongated hole 47 is inserted through the disc spring 54.
It is screwed into the screw hole 42 with the . Another screw 55 also passes through the round hole 48 with a disc spring 56 interposed therebetween, and then passes through the screw hole 43 through a disc spring 57.
is screwed onto. In this way, the pick-up 4 is fixed to the holding member 5. In addition, the disc springs 53, 5
6 is curved in an arc shape toward the holding member 5,
The disc springs 54 and 57 are curved in a circular arc in the opposite direction to the disc springs 53 and 56. Therefore, the pick-up 4 and the holding member 5 are fixed without any play, and the pick-up 4 is fixed to the screw 5 as described later.
When rotating around the axis of 5, pick up 4
The contact area with the holding member 5 is the disc spring 53, 54,
By interposing 56 and 57, the size is reduced and smooth rotation becomes possible.

A moving table 6 is arranged below the pick-up 4 to allow the pick-up 4 to move in the horizontal direction. The movable table 6 is approximately U-shaped with an upward opening. The moving member 6 includes a bottom portion 60 and side portions 61 and 62 erected at both ends of the bottom portion 60. A screw hole 63 is formed near the left end of the bottom portion 60 , and a screw 66 is sequentially inserted through the insertion hole 65 of the leaf spring 64 and the screw hole 63 to fix the leaf spring 64 to the bottom portion 60 . The leaf spring 64 includes a base 64a, and bent parts 64b and 64c that are connected to both ends of the base 64a and gradually move away from the bottom 60 as they extend outward. The lower surface of the protrusion 41 of the pickup 4 can come into contact with the bent portions 64b and 64c of the leaf spring 64.

The side portion 61 has a substantially U-shaped notch 68 at the top,
69 is formed. Also, between the notches 68 and 69 is a support shaft 70 that protrudes outward (to the left in FIG. 12).
will be provided. A support piece 71 is provided on the side of the side plate 61. This support piece 71 has a vertical portion 71a.
and a horizontal portion 7 extending horizontally from the vertical portion 71a.
1b. Fitting holes 73, 7 are provided in the vertical portion 71a.
4 and 75 are formed sequentially along the longitudinal direction. A screw hole 77 into which a screw 76 is screwed is formed in the horizontal portion 71b.

Referring to FIG. 13, the side portion 62 is formed with an extending piece 80 that extends laterally.
Round holes 81 and 82 are formed along the longitudinal direction. In addition, the side portion 62 has a round hole 83 and a round hole 8.
Elongated holes 84 and 85 are formed on both sides of 3. The elongated holes 84 and 85 extend in the circumferential direction of an imaginary circle centered on the round hole 83. A support piece 86 is provided on the outside of the side portion 62. This support piece 8
6 includes a horizontal portion 87 and a vertical portion 88. Screw holes 89 and 90 corresponding to the round holes 81 and 82 formed in the extending piece 80 of the side portion 62 are formed in the horizontal portion 87 . Guide rods 91, 92, and 93 are erected on the vertical portion 88 and protrude inward.

The holding member 5 is attached to the movable table 6 having such a configuration.
gets stuck. To explain in more detail, the guide rods 49 and 50 of the side part 45 of the holding member 5
are fitted into the notches 68 and 69 of the support piece 71, and further fitted into the fitting holes 73 and 75 of the support piece 71, respectively.
At this time, the support shaft 70 of the side portion 61 is loosely fitted into the fitting hole 74 of the support piece 71.

On the other hand, on the other side 62 of the movable table 6, the support piece 8
The guide rod 91 of No. 6 is sequentially inserted through the long hole 84 and the round hole 51c, and the guide rod 93 is inserted through the long hole 85 and the round hole 51a. Further, the guide rod 92 is inserted through the shaft hole 83 via the disc spring 94, and then through the round hole 51b via the disc spring 95, and is fixed by an E ring 96. These disc springs 94, 95 are arcuate,
The top portion is arranged so as to abut against the side portion 62. Such disc springs 94, 95 exhibit the same effect as the disc springs 54, 57 described above.

The support piece 86 also has a horizontal portion 87 resiliently attached to the extension portion 80 . That is, a screw 97 is inserted through the screw hole 84 and further screwed into the screw hole 89 via the coil spring 98, and another screw 99 is also inserted through the screw hole 82 and screwed into the screw hole 90 through the coil spring 100. match. In this way, the holding member 5 is fixed to the movable table 6.

Next, the operation of adjusting the optical axis of the laser beam irradiated from the pickup 4 will be explained. First, when adjusting the optical axis parallel to the moving direction A, use the adjusting screws 97, 9.
By tightening or loosening 9, rotation of the pick-up 4 about the axis of the guide rod 92 of the support piece 86 is effected. More specifically, if the pick-up 4 is tilted counterclockwise in FIG. 3 with respect to the axis parallel to the longitudinal direction, either tighten the adjustment screw 97 or loosen the adjustment screw 98. Perform the following operations. This allows the support piece 86 to move toward the guide rod 9.
Angular displacement in the clockwise direction around the axis of 2. Therefore, the guide rods 91 and 93 angularly displace the holding member 5 in the clockwise direction via the round holes 51c and 51a. As a result, the pick-up 4 is also angularly displaced in the clockwise direction.
It becomes possible to place the pickup 4 in a horizontal state. Note that the guide rods 91 and 93 of the movable table 6 are guided by the elongated holes 84 and 85, so that the movable table 6 is not angularly displaced and is maintained in a horizontal state.

If the pickup 4 is tilted clockwise, contrary to the case described above, either loosen the adjusting screw 97 or tighten the adjusting screw 98. By such an operation, the pick-up 4 is angularly displaced in the counterclockwise direction according to the same operating principle as described above, and it becomes possible to bring the pick-up 4 into a horizontal state.

Next, an adjustment screw 76 is used to adjust the optical axis in a direction perpendicular to the moving direction A and horizontal. By threading the adjustment screw 76, the end of the screw 76 presses the protrusion 41 of the pick-up 4 downward. As a result, the pick-up 4 is angularly displaced around the axis of the screw 55 in a counterclockwise direction.
At this time, the holding member 5 maintains a horizontal state because the screw 52 is guided through the elongated hole 47. Further, by screwing back the adjusting screw 76, the protruding portion 41 is pressed up and down by the elastic force of the leaf spring 64, so that the pick-up 4 is angularly displaced in the clockwise direction. In this way, the pickup 4 can be placed in a horizontal state.

Effects As described above, according to the present invention, the drive motor has
Since the gear head, which houses multiple gear groups inside, is removably attached, the pick-up's moving speed can be easily set by replacing the gear head, reducing the man-hours required for setting the pick-up's moving speed. It can be reduced. Furthermore, since the teeth of the pinion are held between the fixed rack and the movable rack as the backlash absorbing means, the backlash can be reliably absorbed and the responsiveness regarding the movement of the pick-up can be improved.

[Brief explanation of the drawing]

Fig. 1 is an overall perspective view of an embodiment of the present invention, Fig. 2 is a plan view showing a simplified internal structure of the embodiment shown in Fig. 1, and Fig. 3 is a diagram similar to Fig. 2. Figure 4 is a left side view of Figure 2, Figure 5 is a perspective view of Figure 2.
6 is a rear view of FIG. 2, FIG. 7 is a sectional view of the gear head 10, FIG. 8 is a simplified sectional view of the drive motor 8, and FIG. 9 is a perspective view of the bearing 21. , FIG. 10 is a sectional view taken along the section line XX in FIG. 9, FIG. 11 is an enlarged view of the vicinity of the rack part 19,
FIG. 12 is an exploded perspective view of the vicinity of the pickup 4, and FIG. 13 is an exploded perspective view of the pickup 4 as viewed from the side indicated by arrow B in FIG. 1...disk, 4...laser pick-up,
8...Motor, 13...Adjustment screw, 18...Pinion, 21...Bearing, 35...Fixing rack, 3
6...Coil spring, 37...Movable rack.

Claims (1)

[Claims for Utility Model Registration] A power transmission section that transmits output from a drive motor; and a power transmission section that is movable along the radial direction of the disk by the power from the power transmission section, and that emits laser light to the disk during movement. a laser pick-up for detecting a recording signal on the disk by irradiating the drive motor with the drive motor; In the laser pick-up moving device in which the moving speed of the pick-up is changed by changing the voltage applied to the drive motor, a gear head having a plurality of gear groups housed therein is removably attached to the drive motor. is,
A worm is fixed to the rotating shaft of the gear head, and the backlash absorption means includes a fixed rack that meshes with a pinion rotationally driven by the worm, and a movable rack that meshes with the pinion and is movable relative to the fixed rack. , a coil spring having one end fixed to the fixed rack and the other end fixed to the movable rack, and the spring force of the coil spring causes the teeth of the pinion to be sandwiched between the fixed rack and the movable rack. A laser pick-up moving device characterized by pressure.