Recording and/or reproducing apparatus for optical disk

An optical disk recording and/or reproducing apparatus employing a disk cartridge having accommodated therein an optical disk not more than 80 mm in diameter as a recording medium, the apparatus including an outer casing having a length not larger than 112 mm, a width not more than 89 mm and a height not more than 31 mm which encompasses a cartridge loading section, a driving unit for rotationally driving the optical disk, an optical pickup unit and means for transporting the optical pickup unit across inner and outer peripheries of the optical disk driven rotationally by the disk driving unit for recording information signals on or reproducing information signals from a recording surface on the optical disk, a magnetic head unit for generating an external magnetic field based on information signals to be recorded, the magnetic head unit and the optical pickup unit being connected together for movement in unison therewith and arranged facing each other on opposite sides of the optical disk, controlling means for controlling a movement of the magnetic head unit perpendicular to the recording surface of the optical disk as a function of the types of the disks loaded into the apparatus, and a disk loading unit for loading the disk cartridge onto the cartridge loading section and loading the optical disk accommodated in the disk cartridge onto the disk driving unit.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a recording and/or reproducing apparatus for a 
small sized optical disk adapted for recording and/or reproducing 
information signals on or from the optical disk accommodated in a disk 
cartridge. 
2. Description of the Related Art 
There has hitherto been utilized, as an optical recording medium for 
musical sound signals, video signals or other information signals, a 
read-only optical disk on which desired musical sound signals or the like 
are prerecorded and from which the musical sound signals are reproduced on 
loading the disk by the user into a reproducing apparatus. 
There has also been proposed, as an optical recording medium enabling 
signal erasure and re-recording, a magneto-optical disk employing a 
magnetic thin film as a recording layer. 
With the optical recording medium, such as the above mentioned optical disk 
or magneto-optical disk, recording and/or reproduction of information 
signals at an extremely high density is possible because a laser beam is 
utilized for recording and/or reproducing the information signals. With an 
optical disk devoted to reading of prerecorded information signals, such 
as a so-called compact disk, recording of musical sound signals continuing 
for about 74 minutes is possible with a disk size of 12 cm. Recording of 
the information signals of approximately the same volume as that for the 
above mentioned optical disk is possible with the above mentioned 
magneto-optical disk. 
Meanwhile, it has been contemplated to improve further the signal recording 
density on the optical recording medium, such as the above mentioned 
optical disk or magneto-optical disk. For example, for improving recording 
density, there has been proposed a method of compressing information 
signals before recording. 
If such high density recording should be achieved, the same volume of the 
information signals as that achieved with a conventional optical recording 
medium may be recorded with an optical recording medium of a smaller size 
than the conventional recording medium. 
OBJECT AND SUMMARY OF THE INVENTION 
It is a principal object of the present invention to provide a recording 
and/or reproducing apparatus for an optical disk which may be reduced in 
size and rendered portable through the use of an optical disk which is 
markedly reduced in diameter as compared with a conventional optical disk 
through high density recording. 
The present invention provides a recording and/or 
The present invention provides an optical disk recording and/or reproducing 
apparatus employing a disk cartridge having accommodated therein an 
optical disk not more than 80 mm in diameter as a recording medium. The 
optical disk recording and/or reproducing apparatus includes an outer 
casing having a length not larger than 112 mm, a width not more than 89 mm 
and a height not more than 31 mm. The outer casing includes therein a 
cartridge loading section for loading the disk cartridge, a driving unit 
for rotationally driving the optical disk accommodated in the disk 
cartridge, an optical pickup unit transported across inner and outer 
peripheries of the optical disk driven rotationally by the disk driving 
unit for recording information signals on or reproducing information 
signals from a recording surface on the optical disk, a magnetic head unit 
for generating an external magnetic field based on information signals to 
be recorded, the magnetic head unit being arranged for facing the optical 
pickup unit on an opposite side of the optical disk accommodated in the 
disk cartridge, a disk loading unit for loading the disk cartridge onto 
the cartridge loading section and loading the optical disk accommodated in 
the disk cartridge onto the disk driving unit, a battery storage section, 
transporting means for transporting the optical pickup unit across inner 
and outer peripheries of the disk accommodated in the disk cartridge, the 
magnetic head unit being connected to the optical pickup unit for movement 
in unison therewith, and controlling means for controlling a movement of 
the magnetic head unit perpendicular to the recording surface of the 
optical disk as a function of the types of the disks accommodated in the 
disk cartridge loaded into the apparatus. 
With the present recording and/or reproducing apparatus for an optical 
disk, information signals are recorded or reproduced on or from the disk 
on loading the disk cartridge into a cartridge loading section, 
rotationally driving the disk in the disk cartridge by a disk driving unit 
and transporting the optical pickup unit across the inner and outer 
peripheries of the disk. 
The present recording and/or reproducing apparatus for an optical disk is a 
portable type apparatus for recording and/or reproducing the information 
signals because the disk driving unit including a power source, the 
optical pickup unit etc. are enclosed within an outer casing which is 112 
mm or less in length, 89 mm or less in width and 31 mm or less in height.

DETAILED DESCRIPTION OF THE INVENTION 
Before proceeding to the description of a concrete construction of a 
recording and/or reproducing apparatus for an optical disk according to 
the present invention, a disc cartridge as a recording medium employed in 
the present apparatus will be explained. 
Referring to FIG. 1, the disk cartridge 1 has accommodated therein an 
optical disk on which, even though the disk diameter R1 is about 64 mm, 
the same volume of information signals as that recorded on a conventional 
optical disk with the disk diameter of approximately 120 mm, such as a 
so-called compact disk, may be recorded through high density recording. 
That is, the present optical disk, with the thickness of a disk base plate 
of 1.2 mm and a track pitch of the recording track of 1.6 mm, enables 
recording of an information volume corresponding to the musical sound 
signals continuing for longer than 60 minutes and about 74 minutes. 
The optical disk is arranged as a magneto-optical disk 2 making use of a 
photomagnetic recording film as a recording layer to enable erasure and 
rerecording of previously recorded signals repeatedly. 
Referring to FIGS. 1 and 2, the disk cartridge includes a cartridge proper 
5 composed of rectangular upper and lower halves 3 and 4 abutted and 
connected to each other, and the above mentioned magneto-optical disk 2 
rotatably accommodated within the oartridge proper 5. 
Referring to FIG. 2, the lower half 4 of the cartridge proper 5 has a 
central opening 7 for exposing the rim of a centering hole 6 of the 
magneto-optical disk 2 to the outside and into which a disk table of a 
disk driving unit for rotationally driving the optical disk 2 is 
introduced on loading the disk cartridge 1 into the recording and/or 
reproducing apparatus. The lower half 4 also has an aperture 8 adapted for 
radially exposing a part of the signal recording surface of the optical 
disk 5 to the outside for facing an optical pickup unit. The upper half 3 
has an aperture 9 into which a magnetic head is introduced. The apertures 
8 and 9 are provided in register with each other towards a front side 12 
of the cartridge proper 4 transversely centrally between one side 10 and 
the other side 11 of the cartridge proper 5 and are each in the form of a 
rectangle large enough to expose the signal recording surface of the 
magneto-optical disk 2 partially across the inner and outer peripheries of 
the disk. 
A shutter 13 for closing the apertures 8 and 9 is slidably mounted on the 
cartridge proper 5. The shutter 13 is produced by bending a thin metal 
plate or a resin plate or by molding synthetic resin so as to be of a 
U-shaped cross-section. Thus the shutter 13 is composed of a pair of 
shutter sections 15 and 16 connected to each other by a web 14. The 
shutter 13 is slidably mounted on the cartridge proper 5 for clamping the 
front side 12 of the cartridge proper 5 with the shutter sections 15 and 
16 extending over the apertures 8 and 9. A pair of engaging lugs 18 and 19 
for engaging in an engaging groove 17 formed in the lower half 4 are 
segmented from the shutter section 15 in a region close to the web 14. The 
shutter 13 is slidably mounted on the cartridge proper 5 with these 
engaging lugs 18 and 19 engaging in the engaging groove 17 so as to be 
controlled in its sliding movement and prevented from accidental 
extrication. 
Within the cartridge proper 5, there is provided a torsion coil spring 20 
as biasing means for perpetually biasing the shutter 13 in a direction of 
closing the apertures 8 and 9. This torsion coil spring 20 has its one end 
retained by a corner on the front side 12 of the cartridge proper 5 and 
its other end retained by a spring retention section 21 segmented from the 
web 14 of the shutter 13 for biasing the shutter 13 in the direction of 
closing the apertures 8 and 9 as shown by an arrow a in FIG. 2. 
At the other corner on the front side 12 of the cartridge proper 4, there 
is provided a shutter locking member 22 for locking the shutter 13 in the 
position of closing the apertures 8 and 9 when the shutter is at this 
position. The shutter locking member 22 is formed of synthetic resin and 
is flexible or elastically deflectable. The shutter locking member 22 is 
mounted within the inside of the cartridge proper 5 so that a locking 
section 24 having an engaging recess 23 on its lateral side is protruded 
into a shutter opening/closing member inserting groove 25 formed on the 
front side 12 of the cartridge proper 5. When the shutter 13 reaches a 
position of closing the apertures 8 and 9, as shown in FIGS. 1 and 2, the 
shutter locking member 22 locks the shutter 13 in the closure position, 
with a locking piece 26 segmented from the web 14 of the shutter 13 
engaging with the engaging recess 23. 
On the front side 12 of the cartridge proper 5, there is formed the above 
mentioned groove 25 engaged by the shutter opening/closing member provided 
on the recording/reproducing apparatus for unlocking the shutter 13 from 
the shutter locking member 22 and displacing the shutter 13 in a direction 
shown by an arrow B in FIGS. 1 and 2 against the force of the coil spring 
20. The groove 25 is formed over the sliding range of the shutter 13 
beginning from the side 10 of the cartridge proper 5 lying orthogonally 
relative to the sliding direction of the shutter 13. The end of the groove 
25 opening on the side 9 of the cartridge proper 5 is an opening end 25a 
by means of which the shutter opening/closing member provided on the 
recording and/or reproducing apparatus is introduced. 
The lower half 4 of the cartridge proper 5 has a pair of positioning pin 
engaging holes 27, 27 into which positioning pins for setting the 
horizontal loading position of the disk cartridge 1 are engaged on loading 
the disk cartridge 1 into the recording and/or reproducing apparatus. 
The lower half 4 also has disk type discriminating holes 28 and 29 for 
discriminating the types of the optical disks accommodated in the disk 
cartridge 1 and a mistaken recording inhibiting member 30. 
The disk cartridge 5 needs only to be large enough to accommodate the 
magneto-optical disk 2 having the diameter R1 of approximately 64 mm, as 
mentioned previously. Thus the cartridge proper 5 has a width W1 along the 
sliding direction of the shutter 13 equal to 68 mm, a width W2 along the 
direction normal to the sliding direction of the shutter 13 equal to 72 mm 
and a thickness D equal to 5 mm. Meanwhile, the width W2 of the cartridge 
proper 5 normal to the sliding direction of the shutter 13 is selected to 
be larger than the width W1 along the sliding direction of the shutter 12 
in order to conserve a space for accommodating the torsion coil spring 20 
and the shutter locking member 22 on the front side 12 of the cartridge 
proper 5. 
It is noted that, since the magneto-optical disk 2 capable of rewriting 
recorded signals is accommodated in the disk cartridge 1, it is necessary 
for the magnetic head to be introduced into the cartridge proper 5 by 
means of the aperture 9. Thus the cartridge proper 5 constituting the disk 
cartridge 1 is provided with a notch 31 indicating that the disk 
accommodated in the cartridge proper is the overwrite type magneto-optical 
disk 2 and enabling the magnetic head to be introduced into the cartridge 
proper 5. As shown in FIGS. 1 and 2, the notch 31 is provided on the side 
10 of the cartridge proper 5. 
The recording and/or reproducing apparatus according to the present 
invention also has the optical pickup unit, as will be explained 
subsequently, so that a reproduce-only optical disk may also be used as a 
recording medium. 
While the magneto-optical disk 2 has a photomagnetic recording layer on a 
disk base plate having pregrooves as a recording guide, the reproduce-only 
optical disk 202 shown in FIGS. 3 and 4 has a reflection film of Al or Au 
of high reflection index on a disk base plate on which a pattern of 
projections and valleys are formed in a spiral or concentric pattern. 
Alternatively, the reproduce-only optical disk 202 may be the above 
mentioned magneto-optical disk on which information signals are recorded 
previously. Since there is no necessity of providing a magnetic head for 
generating an external magnetic field for recording information signals on 
the magneto-optical disk 2, the upper half 3 of the disk cartridge 200 
accommodating the reproduce-only optical disk 202 is not provided with an 
aperture but is solid throughout in a manner different from the disk 
cartridge 1 accommodating the magneto-optical disk 2. However, a central 
region 3a of the major surface 3a of the upper half 3 is recessed relative 
to a near-by region 3b so as to be used as a region for applying a label 
or the like. The lower half 4 is provided with the aperture 8 to be 
exposed to the optical pickup unit, as shown in FIG. 4. On the other hand, 
since it is unnecessary for the shutter 203 mounted on the disk cartridge 
200 to close the upper half 3 of the cartridge proper 205, the shutter is 
not provided with a section extending over the upper half 3, as shown in 
FIG. 3. However, there is provided a supporting lug 206 for supporting a 
portion of the front side of the upper half 3 for assuring positive 
sliding of the shutter 203 relative to the cartridge proper 205 and 
preventing accidental extrication of the shutter 203 from the cartridge 
proper 205. 
For assuring discrimination between the disk cartridge 1 and the disk 
cartridge 200, the disk cartridge 200 is not provided with the notch 31 
which is provided in the disk cartridge 1 for indicating that the disk is 
the magneto-optical disk. 
It is noted that, except for the above mentioned differences in 
construction, the disk cartridge 200 accommodating the optical disk 202 is 
similar to the disk cartridge 1 as to the size, the mechanism for closing 
and locking the shutter 203 or as to the groove 25 to be engaged by the 
shutter opening/closure member. Therefore, the same parts or components 
are depicted by the same reference numerals and a detailed description is 
omitted for simplicity. 
A magnetic plate 6a is provided about the rim of the centering hole 6 of 
the magneto-optical disk 2 or the optical disk 202 accommodated in the 
disk cartridge 1 or 200 for enabling the disk cartridge 1 or 200 to be 
loaded onto the disk table of the disk driving unit by taking advantage of 
the magnetic force of attraction of magnetic attracting means, such as a 
permanent magnet, provided in the disk driving unit. 
A recording and/or reproducing apparatus for an optical disk, employing the 
above described disk cartridge 1 or 200 as a recording medium, is 
hereinafter explained with reference to FIGS. 5 to 7. 
The recording and/or reproducing apparatus for an optical disk is so 
constructed and arranged that the above mentioned disk cartridge 1 or 200 
is loaded therein and information signals may be recorded on or reproduced 
from the magneto-optical disk 2 or information signals recorded on the 
optical disk 202 may be reproduced from the optical disk 202. 
The recording and/or reproducing apparatus for an optical disk is of such a 
size that the disk cartridge 1 or 200 may be loaded therein and that the 
apparatus may be rendered portable by being held by the user's hand or 
attached to the user's body. Thus an outer casing 50 of the main body of 
the apparatus has a length L of not longer than 112 mm, a width W of not 
wider than 89 mm and a height H of not higher than 31 mm. In the present 
preferred embodiment, the outer casing 50 has the length L of 112 mm, the 
width W of 89 mm and the height H of 31 mm. 
The front side of the outer casing 50 has a cartridge inserting and 
take/out aperture 51 by means of which the disk cartridge 1 or 200 may be 
introduced into or taken out of the outer casing. This cartridge 
inserting/takeout aperture 51 is large enough in size to permit the disk 
cartridge 1 or 200 to be introduced or taken out with the sliding 
direction of the shutter 13 or 203 as the inserting or taking out 
direction. The upper side of the outer casing 50 is provided with control 
buttons for controlling the recording/reproducing operation, such as a 
playback start button 52, a recording button 53, a stop button 54 or a 
playback output adjustment button 55, selection buttons 56 for selecting 
and designating information signals recorded on the magneto-optical disk 2 
or on the optical disk 202, and a display section 57 for displaying 
operating modes of the apparatus or display information for information 
signals being recorded and/or reproduced. A lateral side of the outer 
casing 50 normal to the side thereof provided with the aperture 51 is 
provided with jacks 58, such as a microphone connecting jack, earphone 
connecting jack or the like. The front side of the outer casing provided 
with the aperture 51 is also provided with an eject button 59 for ejecting 
the disk cartridge 1 or 200 loaded into the apparatus. 
A lid, not shown, may be provided to cover the aperture 51 to prevent dust 
and dirt from being intruded into the inside of the outer casing 50. 
Within the above described outer casing 50, as shown in FIGS. 6 and 7, 
there are provided devices or units for recording and/or reproducing 
information signals on or from the magneto-optical disk 2 or the optical 
disk 202, such as a disk loading unit 63 for loading the disk cartridge 1 
or 200 introduced into the outer casing 50 onto a cartridge loading 
section 60 and loading the magneto-optical disk 2 or the optical disk 202 
onto the disk table 62 of the disk driving unit 61, an optical pickup unit 
64 transported across the inner and outer peripheries of the 
magneto-optical disk 2 or the optical disk 202 loaded on and rotated with 
the disk table 62 for recording information signals on the magneto-optical 
disk 2 or reproducing information signals recorded on the magneto-optical 
disk 2 or on the optical disk 202, or a magnetic head device 65 for 
furnishing an external magnetic field for recording information signals on 
the magneto-optical disk 2. 
The cartridge loading section 60, provided within the outer casing 50, is 
provided on a chassis base plate 66, on which the disk driving unit 61 or 
a transporting unit for the optical pickup unit 64 are mounted. Thus the 
cartridge loading section 60 is so designed as to provide a space ample 
enough to load the disk cartridge 1 or 200 above the upper surface of the 
chassis base plate 66. Positioning pins 67 and 68 for engaging with 
engaging holes 27 and 28 in the disk cartridge 1 or 200 are mounted 
upright on the cartridge loading section 60. On loading the disk cartridge 
1 or 200 onto the cartridge loading section 60, the positioning pins 67 
and 68 are engaged in the engaging holes 27 and 28 for loading the disk 
cartridge 1 or 200 in position with respect to the cartridge loading 
section 60. 
At a mid portion of the chassis base plate 66, on which the cartridge 
loading section 60 is mounted, there is mounted the disk driving unit 61 
for rotationally driving the magneto-optical disk 2 of the disk cartridge 
1 or the optical disk 202 of the disk cartridge 200. The disk driving unit 
61 is mounted with a driving motor 69 mounted on the lower side of the 
chassis base plate 66 and with a spindle shaft 70 protruding towards the 
cartridge loading section 60. The distal end of the spindle shaft 70 is 
fast with the disk table 62 for rotationally driving the magneto-optical 
disk 2 or the optical disk 202. Since the disk table 62 is provided with 
the function of rotating the magneto-optical disk 2 or the optical disk 
202 in unison therewith, it is provided with a disk-attracting magnet for 
securing the magneto-optical disk 2 or the optical disk 202 thereto under 
magnetic attraction. 
The optical pickup unit 64 is supported on the chassis base plate 66 by 
means of a feed screw 72 and a feed guide shaft 73 mounted on the lower 
side of the chassis base plate 66 for facing an object lens 71 adapted for 
converging a laser beam on a signal recording surface of the 
magneto-optical disk 2 or the optical disk 202 attached on the disk table 
62. The optical pickup unit 64, supported in this manner, is transported 
across the inner and the outer peripheries of the magneto-optical disk 2 
or the optical disk 202 on actuating a pickup feed motor 74 for 
rotationally driving the feed screw 72. 
It is noted that the pickup feed motor 74 and the feed screw 72 are 
connected to each other by a speed-reducing gearing unit 75. 
The magnetic head unit 65 is connected to the optical pickup unit 64 so as 
to be transported across the inner and outer peripheries of the optical 
pickup unit 64 in synchronism with the optical pickup unit 64. Turning to 
FIG. 9, the magnetic head unit 65 is connected to the optical pickup unit 
64 by having the proximal end of a magnetic head supporting arm 77 
supported by the distal end of a supporting piece 76a upstandingly formed 
on the distal end of a connecting arm 76 having its one end connected to a 
housing 64a for an optical system of the optical pickup unit 64. The 
magnetic head supporting arm 77 is rotatably supported by a pivot 78 with 
respect to the supporting piece 76a so that a magnetic head 79 mounted on 
the distal end of the arm 77 may be moved into contact with or away from 
the magneto-optical disk 2 attached to the disk table 62. Meanwhile, the 
magnetic head supporting arm 77 is rotationally biased by biasing means, 
not shown, in a direction in which the magnetic head 79 mounted on its end 
is slidingly contacted with the magneto-optical disk 2 loaded on the disk 
table 62, with a contact pressure of the order of 2 to 3 g with respect to 
the magneto-optical disk 2. To this end, a member having a surface with a 
low frictional coefficient is formed as one with the magneto-optical disk 
2 on the surface of the magneto-optical disk 2 facing the magnetic head. 
The magnetic head unit 64 need to be so constructed and designed that, when 
the disk cartridge 1 having accommodated therein the magneto-optical disk 
2 is loaded onto the cartridge loading section 60, the magnetic head 79 is 
introduced into the cartridge proper 5 via aperture 9 into sliding contact 
with the magneto-optical disk 2. When the disk cartridge 200 having 
accommodated therein the read- or reproduce-only optical disk 202 and 
hence not provided with the aperture 9 to be exposed to the magnetic head 
is loaded, the magnetic head is maintained at a position removed from the 
surface of the disk cartridge 200 to prevent a sliding contact of the 
magnetic head with the disk cartridge 200 for preventing possible damage 
to the magnetic head 79 due to contact with the disk cartridge surface. 
Thus the present recording and/or reproducing apparatus, into which the 
disk cartridge 1 having accommodated therein the magneto-optical disk 2 
capable of recording information signals or the disk cartridge 200 having 
accommodated therein the read- or reproduce-only optical disk 202 may be 
loaded selectively, is provided with a magnetic head contact/non-contact 
controlling unit 80 for discriminating whether the loaded disk cartridge 
is the disk cartridge 1 or 200 and for controlling the coming into or out 
of contact of the magnetic head 79 with the magneto-optical disk 2 or the 
optical disk 202. Turning again to FIGS. 6 and 7, the controlling unit 80 
is provided inwardly of the cartridge loading section 60 and in opposition 
to the inserting direction of the disk cartridge 1 or 200. 
As shown in FIGS. 8 and 9, the controlling unit 80 is provided with a 
rotation controlling plate 81 for controlling the pivoting of the magnetic 
head supporting arm 77 of the magnetic head unit 64 for controlling the 
coming into or out of contact of the magnetic head 79 with the 
magneto-optical disk 2 or the optical disk 202 on the disk table 62, and a 
cartridge discriminating piece 82 for discriminating between the disk 
cartridge 1 and the disk cartridge 200 loaded on the cartridge loading 
section 60 for controlling the pivoting of the controlling plate 81. The 
controlling plate 81 is rotatably supported on a pivot 84 carried by a 
supporting piece 84a mounted upright on the chassis base plate 66. The 
cartridge discriminating piece 82 is wedge shaped and mounted normal to 
the inner lateral surface of the controlling plate 81. The discriminating 
piece 82 is mounted at a position in register with the magneto-optical 
disk indicating notch 31 formed in the disk cartridge 1 loaded into the 
loading section 60. A rotation-biasing plate 83 is rotatably mounted on 
the pivot shaft 84 with the discriminating piece 82 in-between. The 
rotation-biasing plate 83 and the controlling plate 81 fitted with the 
cartridge discriminating piece 82 are biased toward each other by a 
rotation-biasing spring 85 placed about the pivot shaft 84. The 
controlling plate 81 and the rotation-biasing plate 83, thus unified by 
the rotation-biasing spring 85, are together rotationally biased by a 
torsion coil spring 86 placed about the pivot shaft 84, in a direction 
shown by an arrow O in FIGS. 8 and 9, for rotationally biasing the 
magnetic head supporting arm 77 placed on the controlling plate 81 in a 
direction away from the magneto-optical disk 2 or the optical disk 202 
placed on the disk table 62. The torsion coil spring 86, thus rotationally 
biasing the controlling plate 81 is mounted on the pivot shaft 84 by 
having its one arm 86a retained by the spring-biased plate 83 and its 
other arm retained by a retainer 87 provided on the chassis base plate 66 
for rotationally biasing the rotation-biasing plate 83 and the controlling 
plate 81 in the direction of the arrow O in FIGS. 8 and 9. 
It is noted that the rotation-biasing plate 83 is thrust by a cartridge 
holder 90 as later described or by the disk cartridge 1 or 200 inserted 
into the cartridge holder 90 and thereby rotated against the biasing of 
the torsion coil spring 86, as illustrated in FIGS. 11 and 12. 
Referring to FIGS. 6, 7 and 10, the disk loading unit 63, for loading the 
disk cartridge 1 or 200 inserted via aperture 51 in the outer casing 50 
onto the cartridge loading section 60 is constituted by the cartridge 
holder 90, for holding the disk cartridge 1 or 200 to be loaded into the 
recording and/or reproducing apparatus, an ejection plate 91 for moving 
the cartridge holder 90 vertically with respect to the cartridge loading 
section 60 and for ejecting the disk cartridge 1 or 200 out of the outer 
casing 50, an ejection plate driving unit 92 for sliding the ejection 
plate 91, and a cartridge ejection lever 93 for outwardly ejecting the 
disk cartridge 1 or 200 inserted into and held by the cartridge holder 90 
out of the outer casing 50. 
The cartridge holder 90 is substantially in the form of a flat plate large 
enough to hold the disk cartridge 1 or 200 thereon, and cartridge holding 
sections 94, 95 having U-shaped cross-section are formed on both sides of 
the flat plate for holding the disc cartridge 1 or 200. The side of the 
cartridge holder 90 facing the cartridge inserting/takeout aperture 51 of 
the cartridge holder 90 is opened and functions as a cartridge receiving 
opening 96. A bottom plate 97 of the cartridge holder 90 has an aperture 
98 to be exposed to the optical pickup unit 64 and the disk table 62 
provided on the chassis base plate 66. The outer lateral sides of the 
cartridge holding sections 94, 95 are provided with upstanding guide pins 
98, 99; 100, 101 for guiding vertical movement. The cartridge holder 90 is 
supported by having the guide pins introduced and engaged in guide slots 
104, 105; 106, 107 provided in upright walls 102, 103 on the opposite 
sides of the chassis base plate 66. Each of the guide slots 104, 105; 106, 
107 is composed of a vertical run, such as a vertical run 104a, extending 
parallel to the spindle shaft 70 of the disk driving unit 61, and a 
horizontal section, such as a horizontal section 104b, extending from the 
vertical run 104a towards the cartridge inserting/takeout aperture 51 in 
parallel with the inserting direction of the disk cartridge 1 or 200. The 
cartridge holder 91, supported by the chassis base plate 66 by having the 
guide pins 98, 99; 100, 101 introduced into these guide slots 104, 105; 
106, 107, may be moved vertically in the axial direction of the spindle 
shaft 70 of the disk driving unit 61 and in the inserting/take-out 
direction of the disk cartridge 1 or 200, by the guide pins 98, 99; 100, 
101 being guided along the guide slots 104, 105; 106, 107. 
On an inner lateral side of the cartridge holding section 94 of the 
cartridge holder 90, a shutter opening/closure pin 89 is provided so as to 
be introduced into and engaged with the groove 25 of the disk cartridge 1 
or 200 inserted into the cartridge holder 90 for unlocking the shutter 13 
for opening the shutter 13. 
The ejection plate 91 is a flat plate on opposite sides of which upright 
wall sections 108, 109 are formed. These vertical wall sections 108, 109 
are provided with inclined guide slots 110, 111; 112, 113 in which the 
guide pins 98, 99; 100, 101 provided on the cartridge holder 91 are 
introduced and engaged. These guide slots 110, 111; 112, 113 are inclined 
upwards from the cartridge inserting/takeout opening 51 towards the rear. 
The ejecting plate 91 has a cutout 114 to be exposed to the optical pickup 
unit 64 and the disk table 62 provided on the chassis base plate 66. The 
ejection plate 91 is slidably mounted on the chassis base plate 66 and 
biased inwards as shown by an arrow E in FIG. 6 by a tension spring 114 
installed between it and the chassis base plate 66. With the ejection 
plate 91 biased in this manner, the cartridge holder 90, having the guide 
pins 98, 99; 100, 101 introduced and engaged in the inclined guide slots 
110, 111; 112, 113, is moved in a direction of approaching the disk table 
62. 
The ejection plate 91, thus biased by the tension spring 114, is slid by 
the ejection plate driving unit 92, against the bias of the tension spring 
114, for displacing the cartridge holder 90 to a raised position spaced 
apart from the disk table 62 and horizontally to an ejecting position. The 
ejection plate driving unit 92 is provided with an ejection motor 115 and 
an ejection plate actuating gear 116. The ejecting motor 115 and the 
ejection plate actuating gear 116 are interconnected by a connecting 
gearing 117. An actuating pin 119 for engaging with a retainer 118 
segmented from the forward side of the ejection plate 91 is mounted at an 
offset position of the ejecting plate actuating gear 116. If, with the 
ejecting plate 91 pulled by the tension spring 114 and the disk cartridge 
1 or 200 loaded on the cartridge loading section 60, the ejection button 
59 is actuated for driving the ejecting motor 115 for rotationally driving 
the ejection plate actuating gear 116, the actuating pin 119 abuts on and 
thrusts the retainer 118 for sliding the ejecting plate 91 against the 
bias of the tension spring 114 for shifting the plate 91 to an ejecting 
position. With the ejecting plate 91 thus slid to the ejecting position, 
the cartridge holder 90 is displaced to a raised position removed from the 
disk table 62 while being displaced horizontally to an ejecting position, 
as shown in FIG. 7. 
The ejecting plate 91, thus slid to the ejecting position, is maintained in 
the above mentioned ejecting position, by being locked by a locking lever 
120 (see FIG. 6) actuated into rotation by the cartridge ejecting lever 
93. The locking lever 120 is mounted on the rear side of the chassis base 
plate 66 under the rotational bias of a spring, not shown, so that, when 
the ejecting plate 91 is in the ejecting position, the locking lever 120 
is engaged with a locking piece 121 of the ejecting plate 91 for locking 
the ejecting plate 91 in the ejecting position. 
The cartridge ejecting lever 93 is rotatably supported by a supporting 
shaft 122 mounted on the rear side of the chassis base plate 66 with a 
distal side cartridge thrusting section 93a facing the rear end face of 
the cartridge holder 90, as shown in FIGS. 6, 7 and 10. The cartridge 
ejecting lever 93 is rotationally biased by a tension spring 123 installed 
between it and the upright wall section 103 of the chassis base plate 66 
in a direction shown by an arrow F in FIGS. 6 and 7 in which the cartridge 
thrusting section 93a is protruded inwardly of the cartridge holder 90. 
The mechanical block unit, composed of the disk driving unit 61, optical 
pickup unit 64 and the cartridge loading unit 63 assembled together by the 
chassis base plate 66, is stationarily supported via a vibration damper 
125 on a bottom plate 126 constituting the outer casing 50. 
At the rear side within the outer casing 50 accommodating the above 
mentioned mechanical unit block, a battery storage section 127, 
accommodating a battery for supplying a power source necessary for driving 
the apparatus, is provided and placed on the bottom plate 126; 
A printed circuit board 129 constituting an electric circuit of the 
recording and/or reproducing apparatus is mounted on the bottom plate 126. 
The operation of loading the above mentioned disk cartridge 1 or 200 into 
the recording and/or reproducing apparatus is hereinafter explained. 
In the first place, the operation of loading the disk cartridge 1 having 
accommodated therein the magneto-optical disk 2 is explained. 
For loading the disk cartridge 1, ejection button 59 is actuated for 
displacing the ejection plate 91 to an ejecting position, as shown in FIG. 
7, thereby displacing the cartridge holder 90 towards the cartridge 
inserting/takeout aperture 51 to the raised position removed from the disk 
table 62 of the disk driving unit 61. 
In this state, the disk cartridge 1 is introduced from the aperture 51 into 
the cartridge holder 90 within the outer casing 50, with the sliding 
direction of the shutter 13 as the inserting direction and with the side 
10 as the inserting side. When the disk cartridge is inserted into the 
cartridge holder 90, the shutter opening/closing pin 89 provided on the 
cartridge holding section 94 is intruded into the groove 25 via the 
opening end 25a. When the disk cartridge 1 is further introduced from this 
state into the cartridge holder 90, the shutter locking member 22 is 
flexed by the shutter opening/closing pin 89 for unlocking the shutter 13, 
with the one side of the shutter 13 then abutting on the shutter 
opening/closing pin 89. When the disk cartridge 1 is further intruded from 
this position into the cartridge holder 90, the shutter 13 is displaced 
for opening the apertures 8 and 9 by the shutter opening/closure pin 89 
against the bias of the torsion coil spring 20. The side 10 of the disk 
cartridge 1 then thrusts against the cartridge thrusting section 93a of 
the cartridge ejecting lever 93 provided at the back of the shutter base 
plate 66 for rotating the lever 93 in a direction opposite to that shown 
by an arrow F in FIG. 7 against the bias of the tension spring 123. 
With the cartridge ejecting lever 93 thus rotated, the locking lever 120 of 
the ejecting plate 91 is rotated for unlocking the ejecting plate 91. The 
ejecting plate 91 is slid by the tension spring 114 in a direction shown 
by an arrow E in FIG. 7. At this time, the guide pins 98, 99; 100, 101 are 
moved along the inclined guide slots 110, 111; 112, 113, with the 
cartridge holder 90 being moved in the same direction. Concomitantly with 
the above movement, the guide pins 98, 99; 100, 101 are guided along guide 
slots 104, 105; 106, 107, so that the cartridge holder 90 is lowered along 
the axis of the spindle shaft 70 of the disk driving unit 61 for loading 
the disk cartridge 1 in position on the cartridge loading section 60. 
Simultaneously, the magneto-optical disk 2 is loaded on the disk table 62. 
When the disk cartridge 1 is introduced into the cartridge holder 90 as 
described above, the side 10 of the disk cartridge 1 is faced by the 
cartridge discriminating piece 82 of the control unit 80. When the disk 
cartridge 1 is further introduced into the cartridge holder 90, the side 
10 of the disk cartridge 1 abuts on the cartridge discriminating piece 82, 
at the same time that the side 10 abuts on the rotation-biasing plate 83 
for biasing the plate 83 in a direction shown by an arrow P1 in FIG. 11 
against the bias of the torsion coil spring 86. At this time, if the 
loaded disk cartridge 1 is that accommodating the magneto-optical disk 2, 
the cartridge discriminating piece 82 descends into engagement with the 
magneto-optical disk indicating notch 30 formed in the disk cartridge 1. 
With the cartridge discriminating piece 82 thus engaged with the notch 31, 
the control plate 81 is rotated in unison with the rotation-biasing plate 
83 in a direction shown by an arrow P1 in FIG. 11 under the bias of the 
rotation-biasing spring 85. As a result, the magnetic head supporting arm 
77 of the magnetic head unit 64, so far supported by the control plate 81, 
is no longer supported, so that the supporting arm 77 is rotated towards 
the disk cartridge 1 in a direction shown by an arrow Q in FIG. 11. Thus 
the magnetic head 79 on the distal end of the arm 77 is intruded via 
aperture 9 into the cartridge proper 5 and into contact with the 
magneto-optical disk 2, as shown in FIG. 10. In this state, a recording 
power level light beam is irradiated by the optical pickup unit 64 on the 
magneto-optical disk 2, at the same time that the external magnetic field 
modulated in accordance with information signals by the magnetic head unit 
65 is applied to the magneto-optical disk 2, so that the information 
signals are recorded on the recording film of the magneto-optical disk 2 
in accordance with the direction of the external magnetic field applied by 
the magnetic head unit 65. 
Conversely, if the disk cartridge inserted into the cartridge holder 90 is 
the disk cartridge 200 accommodating the reproduce-only optical disk 202, 
since the magneto-optical disk indicating notch 31 is not provided in the 
disk cartridge 200, the cartridge discriminating piece 82 is supported or 
thrust by the side 10 of the disk cartridge 200, so that the rotation 
controlling plate 81 is rotated in a direction shown by arrow P2 in FIG. 
12 for rotating the arm 77 in a direction away from the disk cartridge 200 
to cause the magnetic head 79 to clear the cartridge proper 5. 
With the above described recording and/or reproducing apparatus for an 
optical disk according to the present invention, it is discriminated 
whether the loaded disk cartridge is the disk cartridge 1 accommodating 
the magneto-optical disk 2 or the disk cartridge 200 accommodating the 
optical disk 1 for selecting the loading state of the disk cartridge. If 
the loaded disk cartridge is the disk cartridge 1 having accommodated 
therein the magneto-optical disk 2, both the optical pickup unit 64 and 
the magnetic head unit 65 are caused to face the magneto-optical disk 2 to 
enable recording and/or reproduction of the information signals. If the 
loaded disk cartridge is the disk cartridge 200 accommodating the optical 
disk 1, the magnetic head unit 65 is displaced to a large extent from the 
disk cartridge 200 to cause the magnetic head 79 to clear the optical disk 
303 to cause only the optical pickup unit 64 to approach and face the disk 
to enable reproduction of the information signals. 
Although the magnetic head contact non-contact controlling unit is adapted 
for detecting the indicating notch 31 provided in the disk cartridge, the 
disk discriminating holes may be used in place of the notch 31, in which 
case the discriminating holes 28, 29 may be detected by electrically or 
mechanically operated detection means and a magnetic head supporting arm 
normally biased in a direction away from the disk cartridge may be driven 
by electro-magnetic driving means so as to be actuated in a direction of 
contacting with the optical disk only when the detection output indicates 
that the disk accommodated in the disk cartridge is the magneto-optical 
disk.