JPH01192019A - Duplicating device for magnetic disk - Google Patents

Abstract

PURPOSE:To accurately align the center of a concentric circular track with a rotational center by providing a means to form a marker on a lengthy original plate, and detecting the center of the track on the original plate by the marker. CONSTITUTION:A master disk in which a large amount of information is recorded on the concentric circular track is transferred on the lengthy original plate 1 by a contact magnetic device 4. The device 4 transfers the marker 10 on the concentric circular track and the concentric circle of the original 1 simultaneously with recording information. The marker 10 is detected by a marker sensor 6, and the center of the concentric circular track is found by calculation. And a center hole is punched in the center by a center hole punching device 7, and a hub is mounted on the center hole by a center hub mounting device 8. Furthermore, the outer peripheral part of a slave disk is punched from the original 1 by an outer peripheral part punching device 9. By punching in such a way, the center of the track can be aligned with the rotational center that is the center of the center hole accurately. In such a way, it is possible to prevent an off-track error from being generated at the time of reproduction even in case of high recording density.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a reproduction apparatus for recorded magnetic disks by contact magnetic transfer.

(Prior Art) As a method of duplicating recorded magnetic recording media at high speed, a master medium on which information has been recorded in advance and a slave medium are brought into contact with each other, and a bias magnetic field is applied to both media. A contact magnetic transfer method is known in which information on a medium is magnetically transferred onto a slave medium.

When applying this contact magnetic transfer method to a magnetic disk, it is important to accurately align the center of the concentric tracks on the slave disk with the rotation center of the disk. If the center of the track and the center of rotation of the disk are misaligned, especially when the information recording density on the disk is high,
This is because off-track errors during reproduction, ie, reading errors due to off-track of the magnetic head, occur frequently.

(Problem to be Solved by the Invention) As described above, in the conventional technology, when duplicating a magnetic disk using the contact magnetic transfer method, it is difficult to correctly align the center of the concentric tracks on the slave disk with the rotation center of the disk. This poses a problem in that off-track errors are likely to occur during playback.

The present invention provides a magnetic disk duplication device using a contact magnetic transfer method, which allows the center of a concentric track on a slave disk to match the rotation center of the slave disk with high accuracy, and does not cause off-track errors. With the goal.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a method for contact magnetically transferring information recorded in advance on a master disk as concentric tracks onto a long master disk serving as a slave disk, while simultaneously transferring concentric tracks on the master disk. Markers are formed on concentric circles. Then, the center of the concentric tracks of the long original plate is detected using this marker, a center hole of the slave disk is punched at the center position, a center hub is attached to this center hole, and the outer periphery of the slave disk is punched. to obtain a recorded magnetic disk.

(Function) In the present invention, the center of the concentric track can be accurately detected after the transfer by using the marker formed at the same time during the contact magnetic transfer. Then, a center hole is formed at the center position of this track, and in order to attach the center hub and punch out the outer periphery of the slave disk, the center of the concentric track on the recorded magnetic disk and the rotation center of the center hole are formed. The centers match exactly.

(Example) Hereinafter, an example in which the present invention is applied to a small floppy disk having a center hub will be described.

FIG. 1 schematically shows the configuration of an apparatus according to a first embodiment of the present invention. As shown in the figure, a long original plate 1 that will become a slave disk is sent out from a delivery roll 2 and wound up on a take-up roll 3. Delivery roll 2
A contact magnetic transfer device 4, a sensor moving mechanism 5, a marker sensor 6, a center hole punching device 7, a center hub attachment C:j device 8, and a peripheral punching device are installed along the path of the long original sheet 1 from the to the winding roll 3. 9 is placed. - The contact magnetic transfer device 4 transfers a master disk (not shown) having a high coercive force magnetic layer, on which information has been magnetically recorded in a large number of concentric tracks, to an original plate 1 having a low coercive force magnetic layer. This is a device that magnetically transfers information recorded on the master disk onto the original disk 1 by applying a bias magnetic field to the original disk 1 and the master disk while bringing the master disk into contact with the master disk. In this embodiment, the contact magnetic transfer device 4 records information on the concentric tracks by magnetically recording markers on the master disk concentrically with the concentric tracks, for example by --like magnetization. When transferring to the original plate 1, this marker is simultaneously transferred to the original plate 1 as shown by reference numeral 10. This marker 10 is detected by the marker sensor 6 and is used to calculate the center of the concentric track transferred onto the original plate 1.

The position of this marker 10 may be at the outermost circumference of the outermost track 11 of the concentric tracks to which information has been transferred, as shown in FIG. The innermost track 12 may be the innermost track 12. That is, the position of the marker 10 may be any position as long as it does not affect the concentric tracks, and may be any position where the marker 10 does not remain on the slave disk when the slave disk is punched out. Further, the marker 10 does not have to be a closed circle, but may be in the shape of a single or multiple arcs as shown in FIG. 2(C).

The sensor moving mechanism 5 uses, for example, an XY table that can move the marker sensor 6 with high precision.

Further, when the marker 10 is magnetically recorded, the marker sensor 6 uses a magnetic head using an MR element (magnetoresistive element), an inductive head, or other magnetic sensor.

Next, the procedure for duplicating a recorded magnetic disk in this embodiment will be explained with reference to FIGS. 2 to 4. first,
As shown in FIG. 2, a concentric track on which information is magnetically recorded and a marker 10 magnetically recorded on the concentric circle are simultaneously transferred onto a long original plate 1 by a contact magnetic transfer device 4. . Next, as shown in FIG. 3, the center O of the concentric tracks recorded on the original plate 1 is detected using the marker 10, and the center hole 13 is punched by aligning the center of the center hole with this center O. . Next, as shown in FIG. 4, the center O of the concentric track is again detected using the marker 10, and the center hub 14 is mounted with the center of rotation of the center hub aligned with the center O. Finally, as shown in FIG. 5, the center 0 of the track is detected using the marker 10, and the outer periphery of the slave disk is punched out by aligning this center 0 with the center of the slave disk. As a result, the information recorded on the master disk is transferred, and the center hole 13 and center hub 1
A magnetic disk (floppy disk) having a predetermined outer diameter and having a diameter of 4 is copied.

Next, a method for detecting the center of a concentric track using the marker 10 will be specifically described. First, as shown in FIG. 6, at least three points PL, P2, . Pa is detected by the sensor moving mechanism 5 while moving the marker sensor 6 on the long original plate 1 in the longitudinal direction of the original plate 1 and in a direction perpendicular thereto, and detects the three points PL, P2 . The position information of P3 is put into a spatially fixed absolute coordinate system and converted into coordinate values.

And these three points PL, P2. The center O of the concentric track is calculated from the coordinate value of P3. The number of points on the marker 10 detected by the marker sensor 6 is not limited to three,
Three points or more is acceptable.

Note that since the marker 10 is made up of one or more circular tracks with a certain width, in order to accurately detect a point on the marker 10, the center of the track that makes up the marker 10 in the width direction must be need to be detected. This method is the seventh
As shown in the figure. When the marker 10 is composed of one circular track, the output of the marker sensor 6 when the marker sensor 6 passes over the marker 10 is as shown in FIG. 7(a), and the maximum of this output is The position where , is the center of the marker 10 in the width direction of the track. When the marker 10 is composed of two circular tracks, when the marker sensor 6 passes over the marker 10, the output of the marker sensor 6 becomes as shown in FIG. 7(b), and the minimum of this output is The position where , is the center of the marker 10 in the width direction of the track. Even when the marker 10 is composed of three or more circular tracks, the width direction of the track of the marker 10 is determined from the maximum or minimum position of the output of the marker sensor 6 when the marker sensor 6 passes over the marker 10. It is possible to find the center.

FIG. 8 shows a second embodiment of the present invention, in which an optically detectable marker 20 is formed on the long original plate 1 instead of the magnetic marker in the first embodiment. is different from the first embodiment. The optically detectable marker 20 is, for example, a hole mechanically drilled to transmit light or made of a material that reflects light, and its shape is not limited to a circle, but may be an oval or other shape. Although the arrangement is circular in the figure, it may be in the shape of a single or plural circular arcs, or may be arranged in other shapes. Also, marker 20
The formation position may be any position as long as it does not affect the track onto which the information is transferred.

In this embodiment, the marker sensor 21 is, for example, an optical sensor such as a plurality of CCD sensors arranged in a plane, an optical sensor using laser light, or the like.

The present invention is not limited to the embodiments described above, and for example, a mechanically detectable marker consisting of a convex portion or a concave portion is used as a marker for detecting the center of a concentric track, and a piezoelectric sensor is used as a marker sensor. A mechanical sensor using a probe or a stylus may also be used.

Furthermore, if there is any difficulty in centering a long original, the long original may be cut into sheets, and then the centers of the concentric tracks may be detected and punched out.

Further, the information magnetically recorded in advance on the master disk may be only a servo signal.

Furthermore, in addition to the apparatus shown in Figures 1 and 8, we also added an automatic feeding mechanism for the center hub, a device that automatically attaches and detaches the slave disk after punching using a suction method, and a device that automatically attaches and detaches the slave disk after punching. By combining a device that automatically sets the cassette so that it does not come into contact with the disc,
It is also possible to further improve mass productivity.

In addition, the present invention can be implemented with various modifications without departing from the scope of the invention.

[Effects of the Invention] According to the present invention, information recorded on a concentric track on a master disk is contact-magnetically transferred to a long original plate serving as a slave disk, and at the same time, a marker is formed on a concentric circle with the concentric track. By detecting the center of the concentric track using this marker, punching out the center hole of the slave disk, attaching the center hub, and punching out the outer periphery of the slave disk enables the detection of the concentric track on the recorded magnetic disk. The center of the center hole can be precisely aligned with the center of rotation, which is the center of the center hole. Therefore, even when the recording density is high, it is possible to copy a magnetic disk without causing an off-track error during reproduction.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a schematic configuration of a magnetic disk duplication apparatus according to a first embodiment of the present invention, and FIG. 2 shows various examples of the positions and shapes of markers on a long original plate in the same embodiment. FIG. 3 is a plan view showing the positional relationship between the marker on the long original plate and the center hole in the same embodiment, and FIG. 4 is a plane view showing the positional relationship between the marker on the long original plate and the center hole in the same example. Fig. 5 is a plan view showing the relationship between the marker and the center hub and the outer peripheral punching position of the slave disk in the same embodiment, Fig. 6 is a diagram showing detection points on the marker in the same embodiment, and Fig. 7 is the same. A diagram schematically showing a change in the marker sensor output when the marker sensor passes through a track constituting a marker on a long original plate in the embodiment, and FIG. 8 is a perspective view showing another second embodiment of the present invention. It is a diagram. 1...Long original plate, 2...Feeding roll, 3...
Winding roll, 4... Contact magnetic transfer device, 5... Sensor moving mechanism, 6.21... Marker sensor, 7...
Center hole punching device, 8... Center hub installation device, 9... Slave disk outer periphery punching device -1
0゜20...Marker, 11...Outermost track, 1
2... Innermost track, 13... Center hole,
14...Center hub. Applicant's Representative Patent Attorney Takehiko Suzue Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] In an apparatus for duplicating a recorded magnetic disk by contact magnetic transfer, information recorded on a master disk as concentric tracks is transferred to a long master disk as a slave disk by contact magnetic transfer, and at the same time, concentric tracks are transferred to the master disk. means for forming a marker on a concentric circle; means for detecting the center of the concentric track on the long original plate using the marker formed by this means; and a slave at the center of the concentric track detected by this means. means for punching a center hole of a disk; means for attaching a center hub to the center hole formed by this means; and means for punching an outer periphery of a slave disk from the long original plate to which a center hub is attached by this means. A magnetic disk duplication device characterized by comprising: