JPH0255871B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a pickup drive device used for reproducing and reading a disc-shaped recording medium.

[Conventional technology]

Conventionally, when a disk-shaped recording medium (hereinafter referred to as an information disk) is rotated and a pickup is moved in the radial direction with respect to the rotating information disk to reproduce and read out recorded information on the information disk, various pickup drive devices have been used. For example, there is a screw shaft type.

In this conventional screw shaft type, a high speed motor is connected to one end of the screw shaft, and a low speed motor is connected to the other end of the screw shaft via a reducer and a clutch. The female threaded body of the pick-up device, which is slidably supported on a guide rod parallel to the The screw shaft is rotated by driving the low-speed motor and the high-speed motor, and the pickup device is moved via the female screw body.

[Problem that the invention seeks to solve]

However, with the above-described device, a clutch is required in addition to a reduction gear on the low-speed motor side. In other words, when driving a high-speed motor, if the low-speed motor remains connected, the load on the reducer will be excessive, so when driving the high-speed motor, the low-speed motor must be disconnected using the clutch. Removing the load.

Therefore, a reduction gear, a clutch, clutch control parts, etc. are required, resulting in a complex structure and high cost.

The present invention is an attempt to solve the above-mentioned problems, and aims to simplify the structure without using a reduction gear, a clutch, etc., and to make it inexpensive.

[Means for solving problems]

The pick-up drive device of the present invention includes a base, a pair of worm shafts rotatably supported in parallel with each other at a distance on the base, and motors respectively connected to the pair of worm shafts. a carriage slidably provided on the pair of worm shafts; a worm wheel rotatably mounted on the carriage and meshed with the pair of worm shafts; a pick-up device provided on the carriage; It is characterized by having the following.

[Effect]

The present invention drives a pair of motors to rotate one or both of a pair of worm shafts to move a carriage having a pickup device via a worm wheel.

〔Example〕

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

In FIGS. 1 and 2, reference numeral 1 denotes a plate-shaped base, and a pair of worm shafts 4 and 5 are mounted on this base 1, spaced apart and parallel to each other via bearings 2 and 3 at both ends. Supports 6 and 7 are rotatably supported on the base 1 at one end of the pair of worm shafts 4 and 5.
Drive shaft 1 of a pair of motors 8 and 9 attached via
0 and 11 are connected via connectors 12 and 13, respectively. One motor 8 is a DC motor for high speed access, and the other motor 9 is a DC motor with a reduction gear for low speed servo.

Reference numeral 15 denotes a carriage, and bearings 16 and 17 are provided on both sides of the carriage 14 and are slidably fitted to the pair of worm shafts 4 and 5, and a support shaft 18 is provided in the center of the carriage 15. A worm wheel 19 is rotatably mounted on this support shaft 18, and this worm wheel 19 is meshed with the pair of worm shafts 4 and 5 on both sides thereof. Furthermore, a pickup device 20 is provided in the carriage 15. This pick-up device 20 is arranged above the base 1 and has a laser emitting section 21, and an arm 2.
A light receiving section 23 is provided below the base 1 via 2 and facing the light emitting section 21 .

The base 1 also has laser beam passage grooves 24 corresponding to the moving parts of the light emitting section 21 and the light receiving section 23.
is formed, and a cutout groove 25 is formed in the base 1 corresponding to the movable portion of the arm 22.

26 is, for example, a flexible transparent information disk on which information is recorded concentrically.

Then, the information disk 26 is placed along the lower surface of the base 1 and rotated.

Then, one or both of the pair of motors 8 and 9 are driven to rotate the pair of worm shafts 4 and 5 in either the forward or reverse direction, thereby rotating the worm wheel 19 and rotating the carriage 15 in either direction. Moving. That is, for example, one motor 8
When the motor rotates forward one rotation, if the other motor 9 is stopped, the carriage 15 moves forward by ₁ If the carriage 15 is moved in the forward direction by _{an X} pitch and then the other motor 9 is rotated one rotation in the reverse direction, the carriage 15 will not move.
Further, when one motor 8 is rotated twice in the forward direction and the other motor 9 is rotated once in the reverse direction, the carriage 15 moves in the forward direction by 1 _X pitch.

In this manner, the pair of worm shafts 4 and 5 are rotated in forward and reverse directions or stopped by the pair of motors 8 and 9, thereby sending the carriage 15 in either direction through engagement with the worm wheel 19.
Then, when the pickup device 20 locates the information disk 26 and fast-forwards, the data is sent at high speed, and when the pickup device 20 plays back or reads the information, the data is sent at low speed. At this time, the carriage 15 moves while being supported by the worm shafts 4 and 5 by bearings 16 and 17 on both sides. Along with this,
Laser light from the light emitting unit 21 of the pickup device 20 is passed through the through groove 24 of the base 1 to the information disk 2.
At the same time, the light that has passed through the information disk 26 is received by the light receiving unit 23, and is converted into an image or image by a playback device and a readout device (not shown).
Play information as audio.

In addition, the worm foil 1 of the carriage 15
9, as shown in FIGS. 3 to 5, two foil plates 31 and 32 of the same shape are superimposed concentrically, and a pin 33 protruding from the upper foil plate 31 and a pin 33 protruding from the upper foil plate 31 are attached. A coil spring 36 is stretched between a pin 35 protruding from the lower foil plate 32 through the long hole 34 of Board 3
The teeth No. 1 and 32 are in a state where they clamp the teeth of the worm shafts 4 and 5, and the backlash between the teeth of the worm shafts 4 and 5 can be reduced and the carriage 15 can be moved stably.

Furthermore, in the above embodiment, the pickup device uses a soft transmissive type information disk, and the pickup device has a light emitting part and a light receiving part. optical reflective,
If a needle contact type device is used, an appropriate device corresponding to the device may be used as the pickup device.

〔Effect of the invention〕

According to the present invention, the pair of motors are driven to rotate one or both of the pair of worm shafts and move the carriage having the pick-up device via the worm wheel. By cooperating or differentially moving the carriage, the feed of the carriage can be easily controlled, and the structure can be simplified without using conventional reduction gears, clutches, etc., and can be provided at low cost.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing one embodiment of the device of the present invention, FIG. 2 is a partially cutaway side view, and FIG.
The figure is a plan view of the worm foil, FIG. 4 is a side view thereof, and FIG. 5 is an enlarged plan view of a portion thereof. 1... Base, 4, 5... Worm shaft, 8, 9...
...Motor, 15...Carriage, 19...Worm wheel, 20...Pickup device.

Claims (1)

[Scope of Claims] 1. A base; a pair of worm shafts rotatably supported in parallel with each other at intervals on the base; a motor connected to each of the pair of worm shafts; a carriage slidably provided on a pair of worm shafts; a worm wheel rotatably mounted on the carriage and meshed with the pair of worm shafts; a pick-up device provided on the carriage; A pick-up drive device characterized by being equipped with.