JPH02110877A - Disk device - Google Patents

Abstract

PURPOSE:To attain stable feed servo by detecting a tilt of a signal conversion head with respect to a horizontal plane and correcting the feed of a feeder with an obtained signal representing the tilt. CONSTITUTION:If a CD player is placed with a tilt, a variable resistor 13 is also tilted by an angle theta with respect to a horizontal plane. On the other hand, a wire 18 with a weight 14 fitted thereto is always suspended in the perpendicular direction. Thus, the contact position of a slider 19 with respect to a resistor 17 is varied with the title angle theta and a voltage division point of a reference voltage Vi given from a reference voltage source 15 is changed. A tilt detection voltage Vtheta obtained at an output terminal 22 is expressed as Vtheta=1/2Vi(1+theta/90), and the said tilt detection voltage Vtheta is inputted to a differential amplifier 10 so that a force opposite in a direction to a force by the self-weight of an optical head 3 is caused in a feed motor 4. Thus, the load of the feed servo is relieved and it is possible to apply proper servo.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disk device such as a CD (compact disc) player, a video disk recording or reproducing device, or a magnetic disk recording or reproducing device.

[Prior Art] A disk recording/reproducing device includes a disk rotation motor, a signal conversion head, and a head feeding device.

[Problem Ui to be Solved by the Invention] By the way, disk devices are not always arranged horizontally. When the disk device is tilted in the feeding direction of the signal converting spatula 1<, the weight of the signal converting head causes abnormal displacement of the signal converting head, which places an unnecessary burden on the feeding servo circuit. In addition, if the motor does not have a holding torque, the signal conversion head moves in the inclined direction during the stop period,
Access time becomes longer. Incidentally, the above-mentioned problems become more noticeable when a linear motor (actuator) is used as the feed device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a disk device that can reliably feed or position a signal conversion head even in a tilted state.

[Means for Solving the Problems] To achieve the above object, the present invention includes a rotating device for a recording medium disk, a signal conversion head for converting a signal in relation to the disk, and a signal conversion head for converting a signal in relation to the disk. a disk drive for feeding in a radial direction; a tilt detection device for detecting an inclination of the signal conversion head with respect to a horizontal plane; and a signal indicating the inclination obtained from the inclination detection device to control the feeding by the feeding device. This invention relates to a tisf device characterized in that it is provided with a circuit for correcting.

[Function] According to the present invention, since the feed is corrected based on the inclination detection, accurate feed is possible.

[Embodiment] Next, a CD player A' according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

As shown in FIG. 1, this CD player includes a motor 2 for rotating a recording medium disk 1, a reproducing optical head (pickup) 3, and a feed motor 4. The optical head 3 projects a light beam 5 onto the disk 1 and detects the reflected beam 6, and is connected to the feed motor 4 by a connecting member 7. Further, a reproduction circuit 8 (demodulation circuit) 8 electrically connected to the optical head 3 obtains reproduction data from an electric signal corresponding to the reflected beam 6, and at the same time obtains a tracking detection signal and a focus detection signal.

l-lagging control circuit 9 connected to regeneration circuit 8
forms a tracking error signal and supplies it to a 1-rack drive unit (not shown) for horizontally moving an objective lens (not shown) built in the optical head 3, and at the same time a differential amplifier. 10 as well.

Speed detection coil 11 associated with feed motor 4
is to apply a speed detection voltage corresponding to the feed speed to the error amplifier 10 in order to realize constant speed feed.

The tilt detection device 12 detects the tilt of the optical head 3, that is, the tilt of the entire CD player, and applies a voltage corresponding to the tilt to the error amplifier 10.

A speed detection coil 1 is connected to one input terminal of the error amplifier 10.
The sum of the speed detection voltage of the first inclination detection device and the inclination detection voltage of the twelfth inclination detection device is input manually, and a tracking error signal is input to the other input terminal. The error amplifier 10 has a dynamic amplification function and drives the feed motor 4 with its output.

As shown in FIG. 2, the tilt detection device 12 includes a variable resistor 13 fixed to a fixed part (for example, a container) of the CD player, a weight 14, and a reference voltage source 15. Variable resistor 1
Reference numeral 3 includes a resistor 17 formed in a semicircular arc shape on a substrate 16 arranged substantially vertically, and a slider 19 attached to a wire 18 that supports a weight 14. wire 1
8 is made of a conductive material and is supported by a protrusion 20 disposed at the center point of the arc of the resistor 17 . Resistor 17σ]
One end 17a is connected to the reference voltage source 15, and the other end 1i7b is connected to ground. A terminal 21 electrically connected to the wire 18 is connected to an output terminal 22 of a pressure V6 for detecting inclination.

The feed motor 4 is shown in principle in FIG. The coil 24 is placed in a magnetic field formed by the magnet 23 , and the optical head 3 is coupled to the coil 24 by a connecting member 7 . The coil 24 is the first
It is connected to the differential amplifier 10 shown in the figure, and when a current flows therein, the coil 24 and the optical head 3 move in the disk radial direction shown by the arrow 25 in FIGS. 1 and 3.

Note that the speed detection coil 11 is coaxially wound around the movable coil 24.

When the CD player shown in FIG. 1 is arranged at an angle, the variable resistor 13 shown in FIG. 2 is also inclined at an angle θ with respect to the horizontal plane. On the other hand, the wire 18 to which the weight 14 is attached always extends in the vertical direction. Therefore, the contact position of the slider 19 with respect to the resistor 17 changes according to the inclination angle θ, and the base i# voltage source 1
The dividing point of the reference voltage 1 given from 5 changes. The slope detection voltage Vθ obtained at the output terminal 22 is expressed by the following equation.

(2) θ=1/2Vi (1+θ/90) This tilt detection pressure Vθ is input to the differential amplifier 10 so that a force opposite to the direction of the force due to the weight of the optical head 3 is generated on the feed motor 4. Therefore, the load on the feed servo is reduced, making it possible to apply appropriate servo9.
In the stop mode, the optical head 3 does not move based on the tilt of the CD player.

[Modifications] The present invention is not limited to the above-described embodiments, and may be modified.For example, the present invention is not limited to optical disc players, but may also be applied to magnetic disc devices using magnetic heads, etc. It is also applicable to

Further, the tilt detection device f12, the sending motor 4, etc. can be modified. Alternatively, data indicating the slope obtained from the slope detection device may be written into a memory, and the data may be read from the memory to perform slope correction control.

[Effects of the Invention] As described above, according to the present invention, stable feed servo is possible, and unnecessary movement of the signal conversion head due to inclination can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a CD player according to an embodiment of the present invention, FIG. 2 is a front view showing an inclination detection device, and FIG. 3 is a sectional view showing the principle of a feed motor. ■... Disk, 2... Motor, 3... Optical head, 4... Feed motor, 5... Beam, 8... Reproduction circuit, 10... Differential amplifier, 12...・Inclination detection device.

Claims (1)

[Scope of Claims] [1] A rotating device for a recording medium disk, a signal conversion head for converting a signal in relation to the disk, and a feeding device for feeding the signal conversion head in a radial direction of the disk. A disk device comprising: a tilt detection device that detects the tilt of the signal conversion head with respect to a horizontal plane; and a circuit that corrects the feeding by the feeding device based on a signal indicating the tilt obtained from the tilt detection device. disk device.