Apparatus for adapting the diameter of a disk-like recording medium

Described is an apparatus for adapting the diameter of the disk-like recording medium. The apparatus includes a supporting member in the form of a ring having an opening for exposing the signal record area of the disk-like recording medium, such as an optical disk, to the outside, and having a diameter larger than the diameter of the disk-like recording medium. The recording medium is integrally retained by a holding system provided to the supporting member for holding the outer perimeter of the recording medium.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to an apparatus for adapting the diameter of a 
disk-like recording medium, such as an optical disk, opto-magnetic disk or 
a magnetic disk, wherein the recording medium is held on the inner 
periphery of a holder to permit the diameter of the disk-like recording 
medium to functionally assume the outside diameter of the holder. 
2. Prior Art 
An optical disk player has been employed in which prescribed information 
signals recorded on an optical recording medium are read and reproduced by 
contactless scanning by an optical pickup device adapted for signal 
reading. 
In the above type disk player, the optical disk has only its central 
non-signal record area clamped by a disk table of a disk driving unit and 
clamping members securely pressured to the disk supporting side of the 
disk table. The optical disk is made as one with the disk table and caused 
to be revolved in unison therewith with the signal record area thereof 
facing to the optical pickup device. 
In the above described disk player having the disk drive unit and the 
contactless optical pickup device, it is necessary that the disk drive 
unit mounting the optical disk and the optical pickup device be accurately 
positioned relative to each other for achieving accurate reading and 
reproduction of the information signals from the optical disk. Thus, in 
this type of the disk player, the disk drive unit is supported with 
accurate positioning by a chassis base plate provided in the main body of 
the player, while the optical pickup unit is slidably supported on a guide 
shaft mounted with accurate positioning to the chassis base plate. 
Thus the disk loading device in which the optical disk employed in the 
above disk player is automatically mounted to the disk drive unit is so 
arranged as to transport only the optical disk for attachment thereof to 
the disk drive unit. 
There is so far known a disk player having a disk loading device such as 
shown in the Japanese Laid-open Utility Model Application No. 145367/1986 
or in the Japanese Laid-open Patent Publication No. 231966/1985. 
In the disk player as shown in the Japanese Laid-open Utility Model 
Publication No. 145367/1986, a disk transfer table 3 on which rests an 
optical disk 2 is mounted so as to be movable into and out of a main body 
of the player 1, see FIG. 1. The disk transfer table 3 is transferred into 
the interior of the main body of the player 1 in the direction shown by 
the arrow mark a in FIG. 2 by a driving gearing 5 actuated by a driving 
motor 4 until the optical disk 2 held in an annular recess 6 formed on the 
table 3 is at a position confronting a disk table 9 of a disk drive unit 8 
supported on a chassis base plate 7 within the main body of the player 1, 
see FIG. 3. A disk supporting member 3a projecting vertically movably from 
the bottom surface of the annular recess 6 for supporting the optical disk 
2 may be actuated so that the optical disk may be placed on and attached 
to the disk table 9 with a central opening 2a of the optical disk 2 in 
alignment with the center of the disk table 9. After the optical disk 2 is 
attached in this manner to the disk table 9, a chucking arm 11 is turned 
towards the disk table 9 in the direction shown by the arrow mark X in 
FIG. 3 until a disk clamper 12 attached to the end of the chucking arm 11 
is pressured onto the optical disk 2 so that the optical disk may be 
revolved in unison with the disk table 9. 
The optical disk 2 thus clamped to the disk table 9 is confronted by an 
optical pick-up unit 14 slidably supported by guide shafts 13, 13 mounted 
to the chassis base plate 7. 
In a disk loading device of the type in which the optical disk 2 supported 
on the disk transfer table 3 movable with respect to the main body of the 
player 1 is mounted on the disk table 9 within the main body of the player 
1, it is necessary that the optical disk 2 be supported at the controlled 
position on the disk transfer table 3, so as to provide for accurate and 
positive attachment of the optical disk to the disk table 9. To this end, 
the annular recess 6 formed on the disk transfer table 3 has the radius 
R.sub.4 corresponding to the radius R.sub.3 ; of the optical disk 2 
supported therein and the outer peripheral surface 2a of the optical disk 
2 is supported by the upright peripheral surface 6a of the annular recess 
6 to control the support position of the disk 2. 
In a disk player shown in the Japanese Laid-open Patent Publication No. 
231966/1985, a disk inserting opening 16 is provided in the main body of 
the player 15, see FIG. 4. In the vicinity of the disk inserting opening 
16, there are provided a stationary guide plate 20 and a movable guide 
plate 19 facing to the stationary guide plate and mounted through the 
medium of the loading arms 18, 18, rotatably supported by frames 17, 17, 
see FIG. 5. The optical disk 2 is adapted to be introduced into the main 
body of the player 15 through a gap formed by these guide plates 19, 20. A 
pair of rolls, that is, a stationary roll 21 and a driving roll 22, each 
having a reduced diameter at the center and having the diameter gradually 
increasing towards both ends, are provided at a position to receive the 
disk 2 inserted through the gap defined between these guide plates 19, 20. 
The optical disk 2 is clamped between these rolls 21, 22. The driving roll 
22 is transferred onto the disk table 9 of the rotary driving unit 8 
mounted in the inside of the main body of the player 15 by a driving 
electric motor 24 through a drive gearing 23 as shown in FIG. 6 for 
mounting the disk. 
In the above disk player, when the optical disk 2 has been transferred onto 
the disk table 9, the loading arms 18, 18 are turned to lower the driving 
roll 22 and the movable guide plate 19 for attaching the disk to the disk 
table 9 with the central opening 2a of the disk 2 in alignment with the 
center of the disk table 9. Following the lowering of the roll 22 and the 
guide plate 19, the chucking arm 11 is turned until the disk clamper 12 
provided to the arm end is pressured onto the optical disk 2 so that the 
disk is clamped for rotation in unison with the disk table 9. 
There is also known a disk player in which the optical disk is not clamped 
automatically to the disk table but in which a cover fitted with a disk 
clamper in opposition to the disk table of the disk drive device mounted 
in a substantially vertical position within the main body of the player is 
mounted for rotation relative to a player cabinet accommodating the main 
body of the player, so that the disk 2 is clamped for rotation in the 
upstanding position. The cover is provided with a disk position regulating 
member adapted for regulating the radial stroke of the disk to provide for 
an optimum disk clamping by the disk clamper and the disk table. This 
cover is rotated with the disk placed thereon with the stroke of the disk 
movement being controlled by the disk position regulating member so that 
the optical disk is clamped to the disk table. 
In the above disk player, the disk position regulating member provided to 
the cover is provided at a position corresponding to the outer periphery 
of the disk for coinciding the central opening of the optical disk with 
the center of the disk table for centering the disk relative to the disk 
table to regulate the position of the optical disk. 
In the above disk players, an optical disk having a predetermined unified 
disk diameter is necessarily employed. Thus the following problems are 
presented when an optical disk having different sizes as described above 
are to be reproduced by the above disk players. In the disk player 
disclosed in the aforementioned Japanese Laid-open Utility Model 
Publication No. 145367/1986, disk movement is regulated with the outer 
peripheral surface 2a of the optical disk 2 abutting on the upright 
peripheral wall 6a of the annular recess 6 formed on the disk transfer 
table 3 for matching the disk position relative to the disk table 9. Thus 
an optical disk other than the optical disk mating with the annular recess 
6 cannot be transported at a predetermined support position. Thus disks of 
different sizes cannot be attached to the disk table 9 with correct 
centering, so that the disk cannot be clamped by the disk clamper 12 for 
rotation. 
In the disk player shown in the aforementioned Japanese Laid-open Patent 
Publication No. 231966/1985, the optical disk 2 inserted through the disk 
inserting opening 16 is clamped by the stationary roll 21 and the driving 
roll 22 so as to be transferred and attached to the disk table 9 in the 
main body of the player 15. Thus an optical disk of a size other than a 
prescribed size cannot be centered with respect to the disk table 9 
because the disk 2 then has a variable transfer stroke such that the disk 
cannot be clamped by the disk clamper 12 for rotation. 
In the above described disk player in which the cover is rotatably mounted 
to the main body of the player and the disk regulated in its position is 
attached to the disk table, position matching between the disk and the 
disk player is achieved by having the outer peripheral edge of the optical 
disk supported as described above. Thus, when an optical disk of a 
different size is placed on the cover and the latter is turned in a 
direction to clamp the optical disk, the center of the optical disk cannot 
be coincided with that of the optical disk or that of the disk clamper and 
thus correct positioning cannot be achieved. Thus it is not possible to 
clamp the disk by the disk table and the disk clamper and thus it is not 
possible to rotate the disk. 
There has been proposed an optical disk having a variable size in 
dependence upon the amount of recorded information. Since the optical disk 
is capable of recording an extremely large number of information signals, 
when recording a small amount of the information signals, such as only one 
or two numbers, the majority of the signal record area remains void or 
free of recorded signals. Thus an optical disk of a reduced size has been 
proposed in order to make an efficient use of the disk material and the 
signal record area so as to provide for simplified handling and to adapt 
the disk to the amount of the recorded information. 
However, such small size optical disk has a drawback that it cannot be 
loaded in the above described conventional disk players for recording or 
reproduction. 
OBJECT AND SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide an apparatus 
for adapting the disk diameter wherein a disk with a diameter less than 
that of a disk having the unified prescribed outside diameter can be made 
to be handled in the same way as the disk of the unified diameter to make 
possible loading thereof into aforementioned conventional extensively 
employed disk players. 
The present invention provides an arrangement wherein the outer periphery 
of the disk-like recording medium is held by the inner periphery of a 
toroidal holder, to the inner periphery of which the disk-like recording 
medium is fitted, in order to provide for unifying the small size disk 
with respect to the size or diameter to the disk of the unified size or 
diameter. 
According to the present invention, the recording medium may be 
substantially assimilated in diameter to the outside diameter of the 
holder, by having the disk-like recording medium, such as the optical disk 
held by holding means provided to the inner periphery of the holder, so as 
to render the holder as one with the disk-like recording medium.

DESCRIPTION OF PREFERRED EMBODIMENTS 
By referring to the accompanying drawings, certain preferred embodiments of 
the present invention wil be explained in detail. 
The first embodiment of the apparatus for adapting the disk diameter 
according to the present invention will now be explained. 
The apparatus shown herein has a toroidal holder 125 having an outside 
diameter R.sub.1 equal to the radius R.sub.3 of the aforementioned optical 
disk 2 which is a conventional socalled compact disk having a unified disk 
size of 12 cm as shown in FIG. 7. 
The holder 125 is formed of synthetic material having prescribed rigidity, 
such as the ABS resin, and has a thickness approximately equal to that of 
the optical disk 2. On the side of the inner periphery of the holder 125, 
there is formed a disk fitting opening 127 in which there is fitted a 
small size disk 126 having a disk diameter R.sub.2, for example 8 cm, 
which is less than that of the aforementioned unified optical disk 2. On 
the periphery of the fitting opening 127, there is mounted a toroidal disk 
holding member 128 made of rubber or the resilient synthetic material as 
the holding means for holding the outer peripheral portion 126a of the 
small size disk 126. As shown in FIG. 9, the disk holding member 128 is 
comprised of a disk holding portion 130 having its inner peripheral 
surface formed with a disk engaging groove 129 adapted for engaging with 
the outer peripheral portion 126a of the small size disk 126, and a pair 
of clamping pieces 131, 132 for the holder 125 extending outwardly from 
the disk holding portion 130. On the inner side of the clamping piece 131, 
there are formed a number of engaging projections 134 adapted for engaging 
in a corresponding number of mating engaging openings 133 formed in the 
holder 125 along the disk fitting opening 127. The disk holding member 128 
arranged and constructed as described above is fitted to the inner 
periphery of the holder 125, as shown in FIGS. 7 and 8, with the clamping 
pieces 131, 132 clamping the periphery of the holder 125 in the vicinity 
of the disk fitting openings 127 and with the engaging projections 134 
engaging with the mating engaging openings 133. 
It is noted that the portion of the holder 125 clamped by the clamping 
pieces 131, 132 is formed with steps 135, 136 and thus reduced in 
thickness such that the clamping pieces 131, 132 lie substantially flush 
with both sides of the holder 125. 
It is noted that, when only one side of the small size disk 126 is designed 
as the signal record surface, the disk 126 can be attached to the optical 
pickup device in the disk player only in a predetermined attachment 
orientation. For indicating the attachment orientation of the small-size 
disk 126, the one surface of the holder 125 is designed as a mirror 
surface 125a, that is, the surface having the same optical properties as 
those of the optical recording medium of the small size disk 126, which 
mirror surface has the appearance similar to that of the signal record 
surface 126b of the small size disk 126. The other surface thereof is 
designed as a printed surface bearing printed handling instructions 
similarly to the other face 126c of the small size disk 126. 
It is noted that, for indicating the attachment orientation of the small 
size disk 126, any other indicating means such as labels or stamping may 
be employed. 
In the above described disk diameter change device, the small size disk 126 
is fitted to the disk holding member 128 with the signal record surface 
126b laying on the same side as the mirror surface 125a of the holder 125. 
When the small size disk 126 is to be introduced into the disk holding 
member 128, the disk engaging groove 129 is deformed resiliently so that 
the outer peripheral portion 126a of the disk 126 is introduced and fitted 
into the disk fitting groove 129 to maintain the small size disk 126 as 
indicated in FIG. 8. 
With the small size disk 126 supported in this manner, the disk 126 is made 
as one with the holder 125 and thus the resulting assembly is equivalent 
to the aforementioned optical disk having the unified disk diameter so 
that the assembly can be handled in the same manner as the aforementioned 
optical disk. 
A second embodiment of the disk radius change device according to the 
present invention will now be explained. 
The apparatus for adapting the disk diameter shown herein also has a 
toroidal holder 141 having the outside diameter R.sub.1 equal to the disk 
diameter R.sub.3 of the optical disk 2 which is the conventional and 
widely employed so-called compact disk with the unified disk size or 
diameter of 12 cm, as shown in FIG. 10, similarly to the preceding 
embodiment. 
The holder 141 is formed of synthetic material having prescribed rigidity, 
such as ABS resin, and has approximately the same thickness as the 
aforementioned optical disk. The inner peripheral side of the holder 141 
is formed with a disk fitting opening 142 into which a small size disk 126 
is fitted having a radius R.sub.2 of, for example, 8 cm, which is less 
than that of the aforementioned unified optical disk, as shown in FIGS. 10 
and 11. On the periphery of the opening 142, the holder 141 is formed with 
three equiangular disk holding sections 143 that may be resiliently 
deflected radially of the holder 141. Each of these disk holding sections 
143 is formed integrally in the holder 141 by forming a pair of slits 144, 
145 radially extending some distance from the disk fitting opening 142 and 
a peripheral slit 146 extending from near the end portions of and between 
these slits 144, 145. The peripheral slit 146 is comprised of a central 
slit portion 146a protruding towards the outer periphery of the holder 141 
and two side slit portions 146bl , 146c extending from both ends of the 
central slit 146a towards the ends of the radial slits 144, 145 and 
protruding in a reverse direction, that is, towards the disk fitting 
opening 142. The disk holding section 143 formed in this manner by boring 
the peripheral slit 146 has its central widened portion 143a supported by 
a pair of continuous narrow arm portions 143b, 143c, and is so designed 
that the widened portion 143a may be supported resiliently and radially of 
the holder 141 within the extent of the gap of the peripheral slit 146 
with the continuous arm portions 143b, 143c being used as the resilient 
deflective portions. 
The side edge of the widened portion 143a of the disk holding portion 143 
towards the disk fitting opening 142 is formed with a disk retaining 
portion 148 protruding towards the disk fitting opening 142 and having an 
engaging groove 147 adapted to be engaged with the outer peripheral 
portion 126a of the small size disk 126, as shown in FIG. 12. Therefore, 
the distance from the center of the holder 141 to the disk retaining 
portion 148 is selected to be smaller than the radius of the small size 
disk 126 approximately by the gap of the peripheral slit 146. The one side 
of each widened portion 143a is formed with a finger rest projections 149 
formed by recesses or grooves for facilitating the operation of 
resiliently deflecting or enlarging the diameter at the disk holding 
portion 143 during the operation of fitting the small size disk 126. 
It is noted that, on the confronting sides of the radially extending slits 
144, 145 and the peripheral slit 146, steps or projections 150a, 150b, 
151a, 151b are formed, as shown in FIGS. 14 and 15. When the small size 
disk 126 is attached to the holder 141 to cause resilient deflection of 
the disk holding sections 143, these steps 150a, 150b, 151a, 151b are 
engaged with one another to close the slits 144, 145 and 146. Similarly to 
the preceding first embodiment, the one side of the holder 141 of the 
present embodiment is formed as a mirror surface 141a having an appearance 
similar to that of the signal recording surface 126b of the disk 126, 
while its other side is formed as a printed surface bearing printed 
handling instructions similarly to the other side 126c of the disk 126, 
for clarifying the attachment orientation of the small-size disk 126. 
When attaching the small size disk 126 to the apparatus as described above, 
the outer peripheral portion 126a of the small size disk 126 is engaged 
with the engaging groove 147 of one of the disk holding portions 143, with 
the mirror surface 125a of the holder 141 lying on the same side as the 
signal recording surface 126b of the small size disk 126, and the disk 
holding section 143 is resiliently deflected to increase its diameter for 
fitting the small-size disk 126 in the disk fitting opening 142. Following 
this operation, the remaining disk holding sections 143 are also 
resiliently deflected by applying finger pressure so as to be increased in 
diameter, the outer peripheral portion 126a of the small-size disk 126 
being engaged in the engaging grooves 147 of these disk holding sections 
143. In this manner, the small size disk 126 is made as one with the 
holder 141 and the resulting assembly has the same diameter as that of the 
aforementioned optical disk having the unified disk size so that it can be 
handled in the same manner as the optical disk. 
It is noted that the confronting sides of the radially extending slits 144, 
145 and the peripheral slit 146 formed in the holder 141, are formed with 
steps or projections 150a, 150b, 151a, 151b meshing with one another to 
close the radially extending slits 144, 145 and the peripheral slit 146 
when the small size disk 126 is held therein as described hereinabove. In 
this manner, when the small-size disk 126 is held and attached to the disk 
player and irradiated with a laser beam from an optical pickup device, 
transmission leakage of the laser beam (or of the light beam from a 
detector in the case of a disk player having a detecting unit adapted for 
detecting the start or end of disk loading by the light beam from the 
detector) may be prevented from occurring. Thus the disk utilizing a laser 
beam may be handled in the same manner as the optical disk having the 
unified disk size. 
It is noted that, for further assuring tight sealing of the small-size disk 
126 during attachment thereof, bosses or projections, not shown, may be 
mounted to one of the disk fitting openings 142 for sealing. 
A third embodiment of the disk size change device according to the present 
invention will be hereafter explained. It is noted that, in the above 
described second embodiment, three equiangular resiliently deflectible 
disk holding sections are provided at the inner periphery of the holder, 
these three disk holding sections holding the small size disk. However, 
only one resiliently deflectible disk holding section may suffice, as 
shown in FIG. 16. 
Similarly to the first and second embodiments, the apparatus for adapting 
the disk diameter shown in FIG. 16 has a toroidal holder 161 having an 
outside diameter R.sub.1 equal to the diameter R.sub.3 of the optical disk 
2 (diameter, 12 cm) which is the so-called compact disk having the unified 
size or diameter. The holder 161 is also formed of synthetic material 
having rigidity similar to the holder of the preceding embodiments, such 
as the ABS resin, and has a thickness approximately equal to that of the 
optical disk. 
The inner periphery of the holder 161 is formed with a disk fitting opening 
162 in which a small size disk 126 having a disk diameter R.sub.2, for 
example 8 cm, which is less than that of the unified optical disk 2, is 
fitted, as shown in FIG. 16. On the periphery of the fitting opening 62, 
supporting tongues 163 adapted for supporting the outer peripheral portion 
126a of the small size disk 126 are projectingly formed from the one main 
surface 161a lying on the same side as the signal record surface 126b of 
the small size disk 126 when the disk 126 is fitted into disk fitting 
opening 162. These supporting tongues 163 are of a sufficiently reduced 
thickness and of a width to support only the non-signal record area of the 
outer peripheral portion 126a of the small size disk 126. On the perimeter 
of the fitting opening 162 and at two places spaced apart a predetermined 
angular distance from each other, there are formed so as to protrude from 
the other main surface 161b facing to the surface provided with the 
supporting tongues 163, thrusting and supporting tongues 164, 164 adapted 
for thrusting and supporting the outer peripheral portion 126a of the 
small size disk 126 in cooperation with the supporting tongues 163. These 
thrusting and supporting tongues 164, 164 are projectingly formed towards 
the inner periphery of the fitting opening 162 and of substantially the 
same width as that of the supporting tongues 163, as shown on FIG. 18. The 
portions of each of the supporting tongues 163 corresponding to the 
positions of the thrusting and supporting tongues 164, 164 are formed as 
recesses 165, 165 in order to assure the withdrawal of the metal mold 
during molding of the thrusting and supporting tongues 164, 164. 
On the perimeter of the fitting opening 162 of the holder 161, there are 
formed disk holding sections 166 integrally with the holder 161, these 
disk holding sections being in register with the thrusting and supporting 
tongues 164, 164 and capable of being resiliently deflected radially of 
the holder 161. The disk holding sections 166 are comprised of a pair of 
cut-outs 167, 168 spaced apart from each other at a prescribed distance 
and extending from the disk fitting opening 162 towards the outer 
periphery of the holder 161, and a peripheral slit 169 extending between 
and from near the end parts of these slits 167, 168. The central slit 
portion 169a of the peripheral slit 169 is protruded towards the outer 
periphery of the holder 161, while the two side slit portions 169b, 169c 
extending from both ends of the central slit portion 169a towards the end 
positions of the cut-outs 167, 168 are protruded in the opposite 
direction, that is, towards the disk fitting opening 162. The disk holding 
section 166 thus formed by boring the peripheral slit 169 is so designed 
that the central widened portion 166a is supported by a pair of narrow 
continuous arm portions 166b, 166c and the widened portion 166a is 
resiliently deflectibly supported radially of the holder 161 within the 
extent of the gap of the peripheral slit 169, with these continuous arm 
portions 166b, 166c as the resiliently deformable portions. 
The side edge of the widened portion 166a of the disk holding section 166 
lying towards the disk fitting opening 162 is provided with a thrusting 
and supporting piece 170 projecting from the other main surface 161b of 
the holder 161 for thrusting and supporting the peripheral portion 126a of 
the small size disk 126, see FIG. 17. The distance from the center of the 
holder 161 to the thrusting and supporting piece 170 is selected to be 
less than the radius of the small size disk 126 approximately by the gap 
of the peripheral slit 169. On the other main surface 161b, the widened 
portion 166a is formed with a finger rest projections 171, formed by 
recesses or slots, for facilitating the operation of resiliently 
deflecting or enlarging the diameter of the disk holding section 166 
during the fitting operation of the small size disk 126. 
The portion of the holder 161 extending from the disk holding portion 166 
to the narrow continuous arm portions 166b, 166c is cut-out on the one 
main surface 161a thereof to provide for reduced thickness of the disk 
holding section 166. In the portion of the peripheral slit 169 
corresponding to the cut-out portion of the holder 161, a step or 
projection 172 is provided for closing the peripheral slit 169 when the 
small radius disk 126 is fitted for resiliently deforming the disk holding 
section 166, see FIG. 19. 
The portions of the holder 161 formed with the cut-outs 167, 168 are formed 
with sealing tongues 173, 173 projecting from the one main surface 161a of 
the holder 161 and extending from the roots of the continuous arm portions 
166b, 166c of the disk holding section 166 to the cut-outs 167, 168, as 
shown in FIG. 20. These tongues 173, 173 are used for preventing the laser 
beam from an optical pickup device provided to the main body of the player 
or the light beam from detecting means adapted for start or termination of 
the disk loading operation from being transmitted through the cut-outs 
167, 168. It is noted that, for assuring resilient deformation or one 
continuous arm portion 166b, 166c, of the disk holding section 166 despite 
the presence of these sealing tongues 173, 173, a slot 174 is formed in a 
manner of dividing the continuous arm portions 166b, 166c as shown in FIG. 
20. 
Similarly to the preceding first and second embodiments, the one side of 
the holder 161 of the present embodiment is formed as a mirror surface 
having an appearance similar to that of the signal record surface 126b of 
the disk 126, while its other side is formed as a printed surface bearing 
printed handling instructions similar to the other side 126c of the disk 
126, for clarifying the attachment orientation of the small size disk 126. 
When attaching the small size disk 126 to the apparatus for adapting the 
disk diameter as described above, the outer peripheral portion 126a of the 
small size disk 126 is caused to rest on the supporting tongues, with the 
one main surface 161a of the holder 161 lying on the same side as the 
signal record surface 126b of the small size disk 126, while the other 
main surface of the small size disk 126 is placed within the disk fitting 
opening 162 as it is thrusted and supported by the thrusting and 
supporting tongues 164, 164. The small size disk 126 is then fitted in the 
disk fitting opening 162 while the disk holding section 166 is resiliently 
deflected so as to be enlarged in diameter, after which the disk may be 
clamped by the supporting tongues 163, thrusting and supporting tongues 
164, 164 and the thrusting and supporting pieces 170 by the springback of 
the disk holding sections 166. As shown in FIG. 21 and 22, the small size 
disk 126 is made as one with the holder 161 so that an assembly having the 
same diameter as that of the aforementioned optical disk with the unified 
disk diameter is provided, which assembly can be handled in the same 
manner as the optical disk. 
A fourth embodiment of the disk size change device according to the present 
invention will be hereafter explained. 
Similarly to the above described preceding embodiments, the disk size 
change device shown herein is comprised of a small size disk 225 having a 
diameter of, for example, 8 cm, which is less than the diameter R.sub.3, 
for example 12 cm, of the aforementioned optical disk which is the 
extensively used diameter. The device further comprises a toroidal a disk 
supporting member 226 having the same outside diameter R.sub.1 as the 
diameter R.sub.3 of the optical disk, and a toroidal disk clamping member 
227 attached to the disk supporting member 226 and adapted for clamping 
the disk 225 in cooperation with the disk supporting member 226, (see FIG. 
23). 
The small size disk 225 has its diameter R.sub.2 less than the diameter of 
the optical disk 2 having the unified disk size or diameter, but it is 
configured in the same manner as the aforementioned optical disk regarding 
the central opening 225a and the non-record area 225b on the perimeter of 
the central opening 225a which is clamped onto the disk table of the disk 
player. 
The disk supporting member 226 is formed of synthetic material, such as ABS 
resin, having the prescribed rigidity, and has a thickness about equal to 
that of the optical disk 2. The inner periphery of the disk supporting 
member 226 is formed with a disk fitting opening 228 for holding the 
signal record surface 225c adapted to be exposed from the central opening 
225a of the small size disk 225, as shown in FIGS. 23 and 24. On the 
perimeter of the disk fitting opening 228 and towards one side 226a of the 
disk supporting member 226 lying on the same side as the signal record 
hold surface 225c when the small size disk 225 is fitted and supported on 
the supporting member 226 there are projectingly formed disk supporting 
pieces 229 on which the disk 225 can be placed with the outer peripheral 
portion 225d of the disk 225 not bearing the information signals being 
supported thereon. Three equiangular resilient thrusting sections 230 are 
formed on the perimeter of the disk fitting opening 228 for clamping and 
supporting the outer peripheral surface of the disk 225. The thrusting 
sections 230 are each comprised of a pair of slits 231, 232 extending 
radially of the disk supporting member 226, a peripheral slit 233 
extending between and near the end portions of these slits 231, 232, and a 
thrusting boss 234 on the inner periphery of the supporting member 226, 
such that the thrusting section 230 may be resiliently deformed radially 
of the supporting member 226. 
On the inner periphery of the other side 226b of the disk supporting member 
226, that is, the surface thereof lying on the same side as a printed 
surface 225e opposite to the signal record surface 225c, and bearing the 
printed information, such as indication of record contents, when the small 
size disk 225 is fitted and supported by the supporting member 226, there 
is formed an attachment portion 235 into which disk clamping projections 
237 are fitted. This attachment portion 235 is formed by forming a step on 
the other side 226b of the disk supporting member 226 to reduce the 
thickness thereat. On the outer periphery of the attachment portion 235, 
there are formed a plurality of, herein six, equiangular openings 237 into 
which are engaged projections 236 formed on the outer periphery of the 
disk clamping member 227. On the inner periphery of each of these openings 
237, there is formed an engaging recess 239 into which is engaged an 
engaging piece 238 provided to the disk clamping member 227. 
On the other surface 226b of the disk supporting member 226 and at a 
position corresponding to each of the openings 237, there is provided an 
indicia 241 for the fitting position corresponding to a mark 240 for the 
fitting position which is provided on the projection 236 of the disk 
clamping member 227. The mark 240 and the indicia 241 may be formed by 
stamping or printing. The projections 236 can be positioned relative to 
the openings 237 by having the mark 240 and the indicia 241 registered 
with each other to facilitate the fitting of the projections 236 into the 
corresponding openings 237. 
The disk clamping member 227 is formed as a disk from resilient synthetic 
material or a thin metal plate such a thin stainless steel plate. On the 
inner periphery of the disk clamping member 227, there is projectingly 
formed a disk clamping piece 242 for clamping the outer peripheral portion 
225d of a small size disk 225 placed on the disk supporting member 226 
through the medium of the disk supporting pieces 229 in cooperation with 
the disk supporting member 227, as shown in FIGS. 25, 26 and 27. The 
projections 236 are formed on the outer periphery of the disk clamping 
member 227. On the outer periphery of these projections 236, engaging 
pieces 236a are projectingly formed for mating with the perimeter of the 
openings 237, such that, when the projections 236 are engaged in the 
openings 237, no gap is formed around the perimeter of the engaging 
openings 237. On the distal side of each of the projections 236, there is 
formed a cut-out 243 designed to permit the projection 236 to be 
resiliently deformed radially of the disk clamping member 227, and the 
aforementioned engaging piece 238 designed to be protruded into the 
cut-out 243. The upper surface of the projection 236 is counterbored at 
244 so as to be used as finger rest projections to facilitate the 
projection 236 to be resiliently deflected towards the outer periphery 
when the projection 236 is fitted into the fitting opening 237 of the disk 
supporting member 226 to cause the projection 236 to be engaged in the 
engaging recess 239. 
It is noted that, when only one side of the small size disk 225 is designed 
as the signal record surface 225c, similarly to the aforementioned optical 
disk, the disk 225 can be attached to the optical pickup device in the 
disk player only in a predetermined orientation. For indicating the 
attachment orientation of the small-size disk, the one surface 226a of the 
disk supporting member 226 is designed as a mirror surface having the 
appearance similar to that of the signal record surface 225c of the disk 
225, while the other surface 226b is designed as a printed surface bearing 
printed handling instructions similarly to the printed surface 225e of the 
disk 225. 
It is noted that any other means may be employed for indicating the 
orientation of attachment of the small size disk 225. 
The operation of having the small size disk 225 clamped by the above 
described apparatus for adapting the disk apparatus will be hereafter 
explained. 
When the small size disk 225 is to be clamped by the disk size change 
device, it is placed on the disk supporting member 226, with the outer 
peripheral portion 225d of the disk 225 retained by the disk supporting 
pieces 229. The projections 236 are then brought to a position in register 
with the openings 237 with the aid of the mark 240 and the indicia 241 on 
the disk supporting member 226, after which the disk clamping members 227 
are placed on the attachment portion 235 of the disk supporting member 226 
in register with the opening 237. Following this operation, the 
projections 236 are deformed towards the outer periphery to widen the 
cut-outs 243, and the projections 238 are brought into positions in 
register with the openings 237 of the disk supporting member 226, from the 
lower side thereof, after which the projections 236 are protruded 
resiliently until the engaging pieces 238 are engaged with the openings 
237 for attachment of the disk clamping member 227 to the disk supporting 
member 226 as shown in FIG. 26. When the disk clamping member 227 is 
attached to the disk supporting member 226 in this manner, the small size 
disk 225 is supported within the disk receiving opening 228 of the disk 
supporting member 226 with the outer peripheral portion 225d thereof 
clamped by the disk supporting pieces 229 of the disk supporting member 
226 and by the disk clamping pieces 242 of the disk clamping member 227. 
With the small size disk 225 being supported by and made as one with the 
disk supporting member 226 as described above, the diameter R.sub.2 of the 
small size disk 225 is assimilated to the outside diameter R.sub.1 of the 
disk supporting member 226 so that the resulting assembly is equivalent to 
the optical disk 2 having the unified diameter R.sub.3 and thus can be 
handled in the same manner as the optical disk 2. 
In the present embodiment, the disk supporting pieces 229 are provided to 
the periphery of the disk receiving opening 228 of the disk supporting 
member 226 and the small size disk 225 is placed in position with the aid 
of the disk supporting pieces 229. However, instead of providing the disk 
supporting pieces 229, retaining steps may be formed on the outer 
periphery of the disk 225 so as to be engaged with the inner periphery of 
the attachment portion 235 for the disk clamping member 227. 
A fifth embodiment of the disk size change device of the present invention 
will be hereafter explained. 
The embodiment shown herein differs from the previously explained fourth 
embodiment with reference to the structure for mounting the disk clamping 
member 227 to the disk supporting member 226. Therefore, in the following 
description, only the portions different in structure from the fourth 
embodiment will the explained, and the description of the common portions 
will be omitted for simplicity. 
The present fifth embodiment is so designed that, after the disk clamping 
member 227 is fitted to the disk supporting member 226, the disk clamping 
member 227 is turned so as to be attached to the disk supporting member 
226. 
As shown in FIGS. 29 and 31, the disk clamping member 227 of the present 
embodiment is provided with a plurality of, herein four, downwardly 
projecting pieces 246 on the outer peripheral portion thereof facing to 
the attachment portion 235 of the disk supporting member 226, these 
projecting pieces engaging in mating engaging slots 245 formed on the 
outer periphery of the attachment portion 235 for the disk clamping member 
227. On the proximate ends of these projecting pieces 246, there are bored 
slits 247 adapted to permit the radial deflection of the projecting pieces 
246. The end part of each of the engaging projections 246 is formed with 
an engaging recess 249 into which an engaging projection 248 engaging with 
the disk supporting member 226 is engaged when the engaging projections 
246 are engaged with the mating engaging slots 245. 
The outer periphery of the attachment portion 235 for the disk clamping 
member is formed with guide pieces 250 adjacent to the engaging 
projections 246, these guide pieces being used as the guide when the disk 
clamping member 227 is engaged with the disk supporting member 226 and the 
projecting pieces 246 are rotated manually into engagement with the mating 
engaging slots 245. On the surface of the guide piece 250, there is formed 
an indicia 253 for indicating the rotary position for each of the 
projecting pieces 246 as by stamping or printing. This indicia 253 is 
associated with indicias 251, 252 on the other surface 226b of the disk 
supporting member 226 indicating non-lock and lock positions for the 
projecting pieces 246 with respect to the mating engaging slots 245, 
respectively. 
As shown in FIGS. 29 and 30, there are formed in the disk supporting member 
226 and on the side of the outer periphery of the attachment portion 235 
for the disk clamping member 227 the aforementioned mating engaging slots 
245 into which are engaged the projecting pieces 246 of the disk clamping 
member 227. The engaging projecting pieces 246 are introduced into 
rotation guide slots 254 formed in continuation with these mating engaging 
slots 245. These guide slots are formed so as to be protruded from the 
outer periphery of the attachment portion 235 for the disk clamping member 
227 towards the outer periphery of the disk supporting member 226 by a 
distance corresponding to the protrusion of the projecting pieces 246. The 
outer peripheral edge of the engaging slot 245 is formed with a retaining 
piece 255 adapted for engaging with the projecting pieces 246 as shown in 
FIGS. 29 and 33. The one surface of the retaining piece 255 is formed with 
the aforementioned engaging projections 248 adapted to be engaged with the 
mating engaging recesses 249 formed at the foremost part of the 
aforementioned projecting pieces 246. The arrangement is so made that, 
when the engaging projections 248 are engaged with the engaging recesses 
249, the engaging projecting pieces 246 are completely engaged with the 
mating engaging slots 245. 
The outer periphery of the attachment portion 235 for the disk clamping 
member is formed with recesses 256 by which the disk clamping member 227 
may be turned within the extent from a position in which the projecting 
piece 246 is within the guide opening 254 to a position in which it is 
locked by interengagement between the guide pieces 250 and the engaging 
recess 249 to facilitate prompt and reliable attachment of the disk 
clamping member 227 to the disk supporting member 226. 
The operation of having the small size disk 225 clamped by the disk size 
change device is hereafter explained. 
For clamping the small size disk 225, the disk is placed on the disk 
supporting member 226, with the outer peripheral portion 225d thereof 
retained on the disk supporting pieces 229, similarly to the fourth 
embodiment described above. 
Then, with the indicia 253 on each guide piece 250 in register with the 
recess 256 of the disk supporting member 226, the disk clamping member 227 
is placed on the attachment portion 235 of the disk supporting member 226. 
When the disk clamping member 227 is placed in this manner, the projecting 
pieces 246 are received within the guide slots 254 as shown in FIGS. 32 
and 33. The disk clamping member 227 is turned from this state in the 
direction of the arrow mark P in FIG. 32, so that the projecting pieces 
246 will be engaged in the mating engaging slots 245. When the disk 
clamping member 227 is turned until the indicia 253 on the guide opening 
254 is in register with the indicia 252, the projecting pieces 246 are 
engaged with the retaining pieces 255, while the engaging projections 248 
are engaged with the corresponding recesses 249 at the end parts of the 
projecting pieces 246 to provide for locking of the engaging projecting 
pieces 246 into the mating engaging slots 245 to complete the attachment 
of the disk clamping member 227 to the disk supporting member 226. 
When the disk clamping member 227 is attached to the disk supporting member 
226 in this manner, the small size disk 225 is supported within the disk 
receiving opening 228 of the disk supporting member 226, with the outer 
peripheral portion 225d thereof clamped by the disk supporting pieces 229 
of the disk supporting member 226 and by the disk clamping pieces 242 of 
the disk clamping member 227. 
With the small size disk 225 being supported by and made as one with the 
disk supporting member 226, as described above, the diameter of the small 
size disk 225 is assimilated with the outside diameter of the disk 
supporting member 226 so that the resulting assembly is equivalent to the 
optical disk 2 having the unified diameter and thus can be handled in the 
same manner as the optical disk 2. 
Instead of providing the disk supporting pieces 229, retaining steps may be 
provided to the outer peripheral edge of the small size disk 225 so as to 
be engaged with the inner periphery of the attachment portion 235 for the 
disk clamping member 227. 
A sixth embodiment of the apparatus for adapting the disk size according to 
the present invention will be hereafter explained. 
The apparatus according to the sixth embodiment is shown in FIGS. 36-43, 
and comprised of a small size disk 325 having a diameter of, for example, 
8 cm, which is less than the diameter R.sub.3 for example, 12 cm, of the 
aforementioned optical disk which is the extensively used conventional 
so-called compact disk having the unified disk diameter, a toroidal disk 
supporting member 326 having the same outside diameter R.sub.1 as the 
diameter R.sub.3 of the optical disk and on which the disk 325 is 
supported, and a disk holding member 327 attached to the disk supporting 
member 326 by being rotated, and adapted for holding the disk 325 in 
cooperation with the disk supporting member 326. 
The small size disk 325 has its diameter R.sub.2 less than the diameter of 
the optical disk having the unified disk size or diameter, but it is 
configured in the same manner as the aforementioned optical disk with 
reference to the central opening 325a and the non-record area 325bwhich is 
clamped onto the disk table of the disk player. 
The disk supporting member 326 is formed of synthetic resin having the 
prescribed rigidity, such as ABS resin, and has a thickness about equal to 
that of the optical disk. The inner periphery of the disk supporting 
member 326 is formed with a disk fitting opening 328 for holding the disk 
the signal record surface 325c being adapted to be exposed from the 
central opening 325a of the small size disk 325, as shown in FIGS. 36 and 
37. On the perimeter of the disk fitting opening 328 and on one side 326a 
of the disk supporting member 326 lying flush with the signal record 
surface 325c when the small size disk 325 is fitted and supported on the 
supporting member 326, there are projectingly formed disk supporting 
pieces 329 on which the small size disk 325 can be placed with the outer 
peripheral portion 325d of the small size disk 325 not bearing the 
information signals being supported thereon. 
On the other surface 326b of the disk supporting member 326, that is, on 
the surface therefor lying flush with the printed surface 325e bearing the 
printed indication of the record contents, viz. the surface opposite to 
the signal record surface 325c when the small size disk 325 is held 
therein, there is formed on the inner periphery thereof an attachment 
portion 330 to which is securely fitted a disk holding member 327. The 
attachment portion 330 is formed by forming a step on the other surface 
326b of the disk supporting member 326 to reduce the thickness thereat. 
The outer periphery of the attachment portion 330 is formed with a pair of 
clamping pieces 332, 333 adapted to support one of a plurality of 
attachment engaging pieces 331 as by clamping from the upper and the lower 
sides, these engaging pieces 331 being formed by bending the outer 
peripheral portion of the toroidal disk holding member 327 attached to the 
outer periphery of the attachment portion 330. On the outer periphery of 
the attachment portion 330 for the disk holding member 327, there are 
formed a plurality of recesses 335 in continuation to the pairs of 
clamping pieces 332, 333, into which are engaged rotation guide pieces 334 
projectingly formed on the outer periphery of the disk holding member 327. 
Thus the extent of rotation of the rotation guide pieces 334 is controlled 
by the corresponding recesses 335 to control the rotary position of the 
disk holding member 327. On the inner periphery of the attachment portion 
330 for the disk holding member 327 and on the inner peripheral end of the 
disk holding member 327, there are projectingly formed cam pieces 338 by 
which resiliently deflectible arms 337 each integrally formed with a disk 
holding piece 336 that may be projected into the disk fitting opening 328 
may be moved radially of the disk holding member 327. 
The disk holding member 327 rotatably mounted to the attachment portion 330 
for the disk holding member is prepared by punching a thin metal plate, 
such as a stainless steel plate, or by molding a synthetic material, into 
the form of a substantially toroidal piece, as shown in FIG. 38. In the 
present embodiment, it is formed by punching a stainless steel plate. 
The rotation guide pieces 334 provided on the disk holding member 327 are 
each formed with a number of radially extending recesses or grooves 339 to 
provide finger rest projections on which a user may act with his finger 
tips to cause rotation of the disk holding member 327. 
The resilient deflectible arm 337 formed with the disk holding member 327 
at the end thereof is formed by boring a slit 340 along the periphery of 
the disk holding member 327. The slit 340 is formed with an arc offset 
with respect to the center of the disk holding member 327. The resilient 
deflectible arm 337 thus formed by boring the slit 340 may be resiliently 
deflected so that the disk holding piece 336 at the end thereof may be 
moved radially of the disk holding member 327 with the proximate portion 
of the disk holding member 327 as center. 
The end part of each resilient deflectible arm 337 is extended as a 
rotation operating piece 341 having a boss 341a on one side adapted to 
engage with a cam piece 338 projectingly mounted to the disk supporting 
member 326. 
The above described disk holding member 327 is attached to the disk 
supporting member 326 by engaging the rotation guide pieces 334 in the 
corresponding recesses 335, clamping the respective engaging pieces 331 
between the corresponding sets of clamping pieces 332, 333 and by engaging 
the rotation operating pieces 341 at the end part of the resilient 
deflectible arms 337 with the cam pieces 338 and may be turned along the 
peripheral direction within the extent of the recesses 334. 
The operating pieces 341 are engaged with engaging projecting pieces 338a 
provided to the cam pieces 338 to prevent incidental extrication thereof 
towards above. 
When only one side of the small size disk 325 is formed as the signal 
record surface 325c, similarly to the above described optical disk, the 
small size disk 325 may be attached to the optical pickup device within 
the disk player only in one attachment orientation. Thus the one side 326a 
of the disk supporting member 326 is designed as the mirror surface 
having the appearance same as that of the signal record surface 325c of 
the disk 325, while on the other side 326b it is designed as a printed 
surface bearing printed handling instructions similarly to the printed 
surface 325e of the disk 325. 
It is noted that any other indicating means may be used for clarifying the 
attachment orientation of the small size disk 325. 
The operation of holding the small size disk 325 by the above described 
apparatus for adapting the disk diameter is hereafter explained. 
For holding the small size disk 325 in the above described manner, the disk 
holding member 327 is turned in the direction of the arrow mark R as shown 
in FIG. 39 to cause the operating piece 341 at the end part of the 
resilient deflectible arm 337 to ride on the cam piece 338 to cause the 
resilient deflectible arm 337 to be turned and offset outwardly of the 
disk supporting member 326 to retract the disk holding piece 336 inwardly 
of the disk supporting member 326. In this state, the small size disk 325 
is placed on the disk supporting member 326 with the outer periphery 325d 
thereof engaged with and retained on the disk supporting piece 329. The 
disk holding member 327 is then turned in the direction of the arrow mark 
Q in FIG. 39 with finger pressure applied to the grooves 339 formed in 
each of the rotation control recesses 334. When the disk holding member 
327 is turned in this manner, the boss 341a of the operating piece 341 is 
disengaged from the cam pieces 338 to cause the resilient deflective arm 
337 to be turned by spring action back towards the inner periphery of the 
disk supporting member 326 to cause the disk holding piece 336 to be 
protruded into the disk fitting opening 328. With the disk holding piece 
336 projected in this manner, the small size disk 325 has its outer 
periphery 325d clamped by the disk supporting piece 329 of the disk 
supporting member 326 and by the disk holding piece 336, as shown in FIGS. 
40 and 42, so as to be retained within the fitting opening 328 of the disk 
supporting member 326. 
With the small size disk 325 thus retained and made as one with the disk 
supporting member 326, the diameter of the small size disk 325 may be 
assimilated, with the outside diameter of the supporting member 326, so 
that the resulting assembly is equivalent with the optical disk 2 having 
the unified size or diameter and thus may be handled in the same manner as 
the aforementioned optical disk. 
The foremost parts of the disk holding pieces 336 are formed with bent 
guide pieces 329 to smooth the operation of holding the the small size 
disk 325. 
Within the recess 335 of the disk supporting member 326 for regulating the 
rotation of the disk holding member 327, there are formed projections 345 
adapted for engaging with the grooves 339 when the small size disk 325 is 
held therein to regulate the rotation of the disk holding member 327. 
In the present embodiment, the operating pieces 341 are provided to the 
foremost parts of the resilient deflective arms 337 and engaged with the 
cam pieces 338. Alternatively, however, the operating pieces 341 may be 
omitted and the intermediate portions of the resilient deflective pieces 
337 may be engaged with the cam pieces 338 to cause the arms 337 to be 
turned and deflected towards the inside and the outside of the disk 
supporting member 326. 
In the foregoing embodiments, description has been made by taking an 
example of an optical disk. However, the present invention is not limited 
to the optical disk, but may be extensively applied to an opto-magnetic 
disk or to a magnetic disk wherein it is necessary to unify the disk to a 
predetermined diameter. 
The outside diameter of the supporting member for the recording medium and 
the diameter of the disk fitting opening can be changed to suit to the 
unified disk diameter or to the diameter of the disk supported in the disk 
holding member. 
From the foregoing it is seen that the present invention provides an 
arrangement in which a disk-like recording medium of a variable size can 
be held on the inner periphery of a holder having a unified outside 
diameter so that the recording medium of a variable size can be adapted to 
the same diameter as that of the recording medium of the unified size or 
diameter. Consequently, a small size disk can be handled in a same way as 
a disk of the predetermined size by the present apparatus having the 
unified predetermined outside diameter so that the small size disk can be 
loaded to conventional extensively employed disk players. 
Also, in accordance with the present invention, the disk-like recording 
medium of variable size can be loaded to one and the same disk player for 
recording and/or reproduction by the same mode of handling and without 
changing the loading unit.