JPH05153793A - Optical disk apparatus - Google Patents

Abstract

PURPOSE:To easily control a microincrement of a supply current of a drive motor by increasing an energizing time of the motor in response to a current supplying times of the motor. CONSTITUTION:A supply current of a drive motor CD (DM) 4 is constant, and supplied for a time (reference energizing time) of an energizing time tau=A. When a tracking error signal (TE) is input to an LPF 5, a high frequency component of the TE is removed, and a low frequency component is input to a comparator(CM) 7. The CM 7 produces an output when the low frequency component of the TE becomes a reference value or more to be obtained by resistors 10, 11. An AND operation of the output of the CM 7 and the output of a CPU 9 is executed by an AND circuit 8, and the circuit 8 produces an output. That is, when a unit additional energizing time is B, a second energizing time tau becomes (A+B). A third energizing time tau is gradually increased to (A+2B). Thus, it is continued until the TE is decreased smaller than the reference value of the CM 7. Thus, a microincrement of a current to the DM 4 can be easily controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc device used for an optical information recording device such as a compact disc.

[0002]

2. Description of the Related Art FIG. 3 shows the structure of an optical pickup feed mechanism in a general optical disc device. In FIG. 3, 1 is an optical pickup, 2 is a guide shaft for supporting the optical pickup 1, 3 is a reduction gear train as reduction means, and 4 is a drive motor for traversing the optical pickup 1.

Next, the operation of the above conventional example will be described. When the drive motor 4 is driven, its rotation is reduced by the reduction gear train 3 and transmitted to the optical pickup 1.
As a result, the optical pickup 1 is traversed along the guide shaft 2.

When performing such an operation, the relationship between the drive current of the drive motor 4 and the displacement of the traverse feed is shown in FIG.
become that way.

That is, due to the static friction between the optical pickup 1 and the guide shaft 2 and the starting current of the drive motor 4, the optical pickup 1 does not actually displace unless the current flows for a certain amount or more. There is a non-linear relationship that causes a large displacement by slightly increasing the current than the current.

FIG. 5 shows the construction of the feed control device of the optical pickup feed mechanism. In FIG. 5, 5 is
A low-pass filter (hereinafter referred to as LPF) that inputs the tracking error signal TE and removes high frequency components, 6
Is an amplifier that amplifies the output of the LPF 5 and drives the drive motor 4.

Next, the operation of the feed control device will be described. The tracking error signal TE is input to the LPF 5, the current is amplified by the amplifier 6, and then the drive motor 4 is driven.

[0008]

However, in such a conventional feed control device, when the drive motor 4 is driven based on the tracking error signal TE, the current value until the rise of the displacement and the rise of the displacement. There is a drawback that a minute increase current must be maintained in a controlled state.

The present invention solves such a conventional problem, and an object of the present invention is to provide an excellent optical disk device capable of easily controlling the supply current to the drive motor of a minute increment. Is.

[0010]

In order to achieve the above object, the present invention provides an optical pickup which is traversed by a rotating magnetomotive force of a drive motor through a speed reducing means, a tracking error signal and a reference voltage of the optical pickup. The comparator outputs a signal when the tracking error signal becomes larger than the reference voltage, and the energization time for energizing the drive motor based on the output signal of the comparator is A reference energizing time is A, a unit additional energizing time is B, and the number of times of supplying a current to the driving motor is N, a control means for controlling in a relation of τ = A + (N−1) × B And

[0011]

Therefore, according to the present invention, the energization time to the drive motor can be increased according to the number of times the current is supplied to the drive motor. Therefore, a minute increase in the current supplied to the drive motor can be achieved. It has the effect of making control easy.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a schematic structure of a feed control device of an optical pickup feed mechanism in an optical disc device according to an embodiment of the present invention. In FIG. 1, the same elements as those of the feed control device in the optical pickup feed mechanism of the conventional optical disk device of FIG. 5 described above are designated by the same reference numerals as those in FIG. With
The description is omitted. And in FIG. 1, 7 is L
A comparator that compares the output of the PF5 with a predetermined reference value and outputs a signal when the output of the LPF5 becomes equal to or higher than the reference voltage. The reference voltage is a resistor 10 and a resistor connected between the power source V and ground. It is obtained by the potential of the connection point with 11.

Reference numeral 8 denotes an AND circuit for ANDing the output of the comparator 7 and the output of the central processing unit 9 (hereinafter referred to as CPU) as a control means, and 12 amplifies and drives the output of the AND circuit 8. It is an amplifier that drives the motor 4 for use.

The drive motor 4 traverses the optical pickup 1 shown in FIG. 3, and is a DC motor.

The CPU 9 is driven by the drive motor 4
Is to control the energization time to the drive motor 4. Specifically, the energization time to energize the drive motor 4 is τ, the reference energization time to the drive motor 4 is A, and the unit additional energization time to the drive motor 4 is Is B and the number of times the current is supplied to the drive motor is N, the control is performed in the relationship of τ = A + (N−1) × B ... (1).

Next, the operation of the above embodiment will be described. In the above embodiment, the CPU 9 controls the control as shown in FIG. FIG. 2 shows the operation of the CPU 9 with the horizontal axis representing the current supply circuit N to the drive motor 4 and the vertical axis representing the energization time τ to the drive motor 4.

That is, the electric current supplied to the drive motor 4 is set to a constant value, and the time of the energization time τ = A (reference energization time A) is supplied for the first time. Here, the tracking error signal TE
Is inputted to the LPF 5, the high frequency component of the tracking error signal TE is removed at this LPF 5, and only the low frequency component thereof is extracted.

After that, the low frequency component of the tracking error signal TE passing through the LPF is input to the comparator 7. The comparator 7 outputs the tracking error signal T
E is compared with the reference voltage obtained by the resistors 10 and 11, and when the low frequency component of the tracking error signal TE becomes equal to or higher than the reference value, a signal is output from the comparator 7, and this output signal is output from the CPU 9 and the AND circuit. AND is taken at 8 and output from the AND circuit 8.

As described above, the LPF is output from the comparator 7.
The tracking error signal TE passing through 5 is output every time the reference value is exceeded, and the output from this comparator 7 is CP.
Each time it is input to U9, the number of energizations N to the drive motor 4 N
Is increasing.

When the UPU 9 outputs to the other input terminal of the AND circuit 8 in order to energize the drive motor 4 for the second time, the second energization time τ is τ as shown in FIG. = A + B, and similarly, for the third energization time τ, the energization time to the drive motor 4 is gradually increased by gradually increasing the time by τ = A + 2 × B as shown in FIG. To the tracking error signal TE, which is continued until the tracking error signal TE falls below the reference value of the comparator 7.

As a result, the minimum value of the distance required for the drive motor 4 to traverse the optical pickup 1 can be controlled by the time width of the unit additional energization time B to the drive motor 4.

As described above, according to the above-described embodiment, the current is supplied with the first energization time to the drive motor 4 as the reference energization time A, and the tracking error signal TE is obtained as a result of the comparison of the comparator 7 after the second time. Is higher than the reference value, the energization time τ is τ = A + (N-1) × B (however, N
Is a number of times the current is supplied to the drive motor, B is a unit additional energization time), and the tracking error signal TE is continuously supplied while adjusting the tracking error signal TE to be smaller than the reference value. This has the advantage that it is possible to easily control a minute increase in the current to the drive motor 4.

[0023]

As described above, according to the present invention, the optical pickup traversed by the rotating magnetomotive force of the drive motor through the speed reducing means, and the tracking error signal of the optical pickup is compared with the reference voltage. Is greater than the reference voltage, a comparator that outputs a signal, the energization time for energizing the drive motor based on the output signal of the comparator, the energization time for energizing the drive motor is τ, and the reference energization time is A, When the unit additional energization time is B and the number of times of current supply to the drive motor is N, the control means for controlling in a relation of τ = A + (N−1) × B is provided.
The energization time to the drive motor can be increased according to the number of times the current is supplied to the drive motor, thus facilitating the control of a minute increase in the supply current to the drive motor. Have.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a feed control device of an optical pickup feed mechanism in an optical disc device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating an operation of a CPU in the same device.

FIG. 3 is a side view of a pickup feeding mechanism in a conventional optical disc device.

FIG. 4 is an explanatory diagram showing the relationship between the current supplied to the drive motor and the displacement of the optical pickup in the optical pickup feeding mechanism of the conventional optical disc device.

FIG. 5 is a block diagram showing a schematic configuration of a feed control device in a conventional optical pickup feed mechanism.

[Explanation of symbols]

 1 Optical pickup 3 Reduction gear train 4 Drive motor 7 Comparator 9 CPU

Claims (1)

[Claims] 1. An optical pickup which is traversed by a rotating magnetomotive force of a drive motor through a speed reducing means, and a signal when a tracking error signal of the optical pickup is larger than a reference voltage as compared with a reference voltage. Based on the output signal of this comparator, the energization time for energizing the drive motor is τ, the energization time for energizing the drive motor is τ, the reference energization time is A, the unit additional energization time is B, and the drive is An optical disk device comprising: a control unit that controls in a relationship of τ = A + (N−1) × B, where N is the number of times of current supply to the motor for driving.