JPH01319171A - Disk normal mount detecting device - Google Patents

Abstract

PURPOSE:To know dislocation between a disk center and a spindle motor shaft and a miss clamp by positioning a reflection type detector, which is composed of a light emitter and a light receiver, in the outer-most circumference of a disk. CONSTITUTION:The reflection type detector to be composed of a light emitter 3 and a photo-detector 4 is arranged on a pick-up 5 and further, the pick-up 5 is moved near the outer-most circumference of a disk 2 by a driving mechanism 6, a position detecting device 7 and a driving device 8. Under the miss clamp condition that the center of the disk 2 and the shaft of a spindle motor 1 are dislocated, an output voltage from the photo-detector 4 is fluctuated since the outer-most circumference position of the disk is changed. Thus, the fluctuation of the output voltage is detected by a comparator 9 and it can be known that the disk 2 is decentered.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for detecting whether a disc has been correctly loaded in a video disc player.

[Prior Art] Such a conventional device uses a reflection type detector to determine the inclination of the disk surface, as shown in Japanese Utility Model Application No. 60-9018 (Optical recording information reading device E). , the pickup was rotated so that it was parallel to the disc.

[Problem to be Solved by the Invention] The above-mentioned conventional technology does not take into consideration the point of detecting that the disk is rotating eccentrically due to misclamping, and for that purpose, other eccentricity detection methods are required. There was a problem that required the use of a container.

An object of the present invention is to use a reflection type detector for detecting the inclination of the disk to detect the eccentricity of the disk and to know that the disk has been misclamped.

[Means for Solving the Problems] The above purpose is to rotate the disk by disposing a reflective detector near the outermost circumference of the disk, and to change the outer circumferential position of the disk as the output signal from the reflective detector changes. means,
You can tell if you have misclamped.

[Effect] The emitter and receiver constitute a reflective detector.

When there is a disk above the emitter, the light is reflected and returns to the receiver, so a higher voltage is output than the receiver.

When there is no disk, no light returns, so a low voltage is output. This makes it possible to know whether or not there is a disk above the light emitter. Since the outermost circumferential dimension of the disk is determined by standards, a reflective detector is installed at this position to rotate the disk. At this time, if the disc is eccentric due to misclamping, the state of the disc on the first reflection type detector will be repeated as present/absent, then present/absent, and the output voltage of the photoreceiver will fluctuate. If this variation is detected, it can be determined that there is a misclamp.

[Example] An example of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is an explanatory diagram showing one embodiment of the present invention, and FIG.
The figure is a top view of the main parts.

A reflective detector consisting of a light emitter 3 and a light receiver 4, as shown in FIGS. , is moved to the vicinity of the outermost circumference of the disk 2 by the drive device 8. When the disk 2 is rotated by the spindle motor 1 in this state, the outermost circumferential position of the disk does not change, so that the light receiver 4 outputs a constant voltage. However, as shown in FIG. 2, in a misclamped state where the center of the disk 2 and the axis of the spindle motor 1 are different, the output voltage from the light receiver 4 fluctuates because the outermost circumferential position of the disk changes. This variation in output voltage is detected by the comparator 9, and it can be determined that the disk 2 is eccentric.

[Effects of the Invention] According to the present invention, the displacement between the disk center and the spindle motor axis can be detected using a reflective detector composed of a light emitter and a light receiver. The above detector can be used in common with the detector used to maintain parallelism between the disk and the pickup, so the mechanism can be simplified.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing one embodiment of the present invention, and FIG. 2 is an explanatory diagram showing an embodiment of the present invention.
FIG. 6 is a top view of a case where the disk center and spindle axis are different due to misclamping. Explanation of symbols 1...Spindle motor 2...Disk 3.
...Emitter 4...Receiver 5...Pickup 6...Drive mechanism 7...Position detection device 8...Drive device 9...Comparator〆'

Claims (1)

[Claims] 1. In a video disc player, a light emitting means for emitting light toward the disc, a light receiving means for receiving the light reflected by the disc, and a light emitting means and a light receiving means for receiving the light reflected from the disc; means for positioning the disc at a position corresponding to the outermost circumferential position; and when the disc is rotated, the output signal of the light receiving means fluctuates between presence and absence, so that the center of the disc is deviated from the center of rotation. What is claimed is: 1. A disk normal mounting detection device comprising: means for detecting;