JPH0432466B2 - - Google Patents

Description

Detailed Description of the Invention "Industrial Application Field" The present invention places a disc on a turntable, moves a pick-up in a radial direction with respect to the axis of the disc, and collects information (music) recorded on the disc. The present invention relates to a disc playback device that reads and plays back discs.

``Prior Art'' Conventionally, there has been a technique in which a pickup is moved to a desired position on a plurality of tracks formed on a disk, and desired information is read and reproduced.

"Problems to be Solved by the Invention" The conventional technology consumes less current (approximately 700 to 800 milliamps) when searching for tracks, compared to the current consumption (approximately 400 milliamps) during playback operation.
Therefore, in a portable type that uses a battery as a power source, for example, when searching one track from the outer circumference to the inner circumference of the disk after playing all the music recorded on the disk, the voltage will increase due to the increase in current consumption. There were problems such as descending, degrading the focus function of the pickup, and making it impossible to perform track exploration properly.

``Means for Solving the Problems'' However, the present invention provides a device that includes a disk motor that rotates a disk and drives and controls the disk motor via a disk motor driver, using a pulse signal to control the movement of a pickup. The present invention is characterized in that a means for lowering the input level of the disk motor driver is provided, and the input level of the disk motor driver is lowered when performing a disk track search.

"Function" Therefore, it is possible to reduce the current consumption of the disk motor driver, which consumes the most current when searching for a track, and to prevent a drop in the power supply voltage, thereby preventing a drop in the focus function of the pickup.
This allows the disk track search to be carried out properly, significantly extends the life of the battery used as a power source, and achieves these effects by lowering the input level of the disk motor driver.
The current consumption can be reduced even if the disk motor and the pick-up movement motor are started at the same time, and the rotational speed of each motor is lower than when the disk motor and the pick-up movement motor are not started at the same time. Since there is no need for a detection circuit or a timing shift circuit, the above effect can be obtained at low cost with a simple structure. In addition, since the disk motor and pick-up movement motor can be driven simultaneously, track search can be performed to obtain arbitrary information (music). ), it is possible to shorten the time required to reproduce the data, and it is possible to prevent functional deterioration due to reduction in current consumption.

"Example" Hereinafter, an example of the present invention will be described in detail based on the drawings. The drawing is an electrical circuit diagram of a main part of a portable disk playback device, which includes a disk motor 1 that rotates an optical disk (compact disk) on which information such as music is recorded, and a control signal that drives the disk motor 1. When a signal is applied to the input terminal 2, the disk motor 1 is driven and controlled via a disk motor driver 3 that operates based on the control signal, and the disk mounted on the turntable is rotated at a constant speed.

Further, a transistor 5 is provided as means for lowering the input level of the disk motor driver 3 using a pulse signal 4 for controlling the movement of a pickup that irradiates a laser beam onto the disk and reads information, and the collector of the transistor 5 is grounded. ,
Further, the emitter of the transistor 5 is connected to the input line 6 of the disk motor driver 3, and the base of the transistor 5 is connected to the control terminal 7 to which the pulse signal 4 for controlling the movement of the pickup is input. The H level output 4a is set to move the pickup toward the outer circumference of the disk, and the L level output 4b of the pulse signal 4 is set to move the pickup toward the inner circumference of the disk.
When the transistor 5 is made conductive by the L level output 4b of the disc, for example, when all the music has been played and a track search is performed on the disc in order to move the pickup from the outer periphery of the disc to the one track position on the inner periphery, the pulse signal The transistor 5 is configured to lower the input level of the disk motor driver 3 based on the L level output 4b of the transistor 4.

This embodiment is configured as described above, and conventionally,
Current consumption during disk playback (400mA)
The current consumption (700 to 800 milliamps) when searching for a track was significantly increased compared to the previous model, but the disk motor driver 3 consumes the most current when searching for a track.
Compared to the current consumption of the driver 3 during playback (30 milliamps), the current consumption of the driver 3 during track exploration is
Since the current consumption (390 to 540 milliamperes) of the driver was rapidly increasing, the input level of the driver 3 was lowered (about 16 dB) using the pulse signal 4 that moves the pickup toward the inner circumference of the disk.
Reduces current consumption during track exploration (approximately
200 mA), which prevents the focus function from deteriorating during track exploration, and shortens the battery life used as a power source from 2.5 hours to 3.5 hours.
It was possible to extend the time.

``Effects of the Invention'' As is clear from the above embodiments, the present invention provides a device that includes a disk motor 1 for rotating a disk, and controls the movement of a pickup in a device that drives and controls the disk motor 1 via a disk motor driver 3. Means 5 for lowering the input level of the disk motor driver 3 using the pulse signal 4
is configured to reduce the input level of the disk motor driver 3 when performing a disk track search. This can be easily reduced, preventing a drop in the power supply voltage and deteriorating the focus function of the pick-up, allowing the disk track search to be performed properly, and significantly shortening the life of the battery used as a power source. Moreover, since these effects are obtained by lowering the input level of the disk motor driver 3, the current consumption can be reduced even if the disk motor 1 and the pick-up movement motor are started at the same time, and the disk motor 1 Compared to a system that reduces current consumption by not starting the pick-up motor and the pick-up motor at the same time, it eliminates the need for a rotation speed detection circuit for each motor or a circuit that shifts the timing, and achieves the above effect at low cost with a simple structure. In addition, since the disk motor 1 and the pick-up moving motor can be driven simultaneously,
This has the advantage of being able to shorten the time it takes to search for a track and play back arbitrary information (music), and to prevent functional deterioration due to reduced current consumption.

[Brief explanation of drawings]

The drawing is an electrical circuit diagram of a main part showing an embodiment of the present invention. 1... Disc motor, 3... Disc motor driver.

Claims (1)

[Claims] 1. In a device that is equipped with a disk motor that rotates a disk and that drives and controls the disk motor via a disk motor driver, a device is provided that lowers the input level of the disk motor driver using a pulse signal that controls the movement of a pickup. 1. A disc playback device characterized in that the input level of a disc motor driver is lowered when a track search is performed.