A Cartridge for an Optically Readable Data Carrier, a Cartridge with Such a Data Carrier and a Player for Such a Cartridge with Such a Data Carrier
This invention relates to a cartridge for an optically readable data carrier, e.g. compact disc (CD), compact disc-read only memory (CD-ROM), and digital versatile disc (DVD), a cartridge with such a data carrier, and a player for such a cartridge.
Background of the Invention Optically-readable data carriers, in particular optical discs, are widely available nowadays for numerous applications. Common applications include CD's for storing music, CD-ROM's for storing computer programs and such information as encyclopedias and dictionaries, DVD's for audio-visual entertainment as well as recording purposes, and writable CD's to which data may be written and/or over-writable by the end user. An optical disc is comprised of a number of discrete layers. The data layer will store the data in the form of a number of microscopic pits to be read by a laser emitted by an optical disc reader. The data layer is enclosed within a number of protective layers, from top and bottom. The bottom layers, commonly referred to as the "read-side" of the disc, are transparent substrates which allow the laser to pass through to read the data. On the top of the disc is a reflective layer which is in turn protected by a discrete protective layer and a graphic layer, which normally supports the label and information pertaining to the content of the disc. The reflective layer reflects the data-enriched laser beam to a receiver of the playing device where the data is read and interpreted for the user. The physical size of currently available CD, VCD and DVD systems, including both the disc and the play-back device, or more conveniently called player, are rather bulky and not easily portable. A player for an optically-readable data carrier is here meant to include, but is not limited to, CD players adapted to read data from CD's, CD-ROM players for reading data from CD-ROM's, e.g. those installed in personal computers and laptop computers, DVD players adapted to read data from DVD's, and CD- Write device adapted to write and/or over-write data onto a CD, CD-ROM or DVD.
In all such conventional systems, the user has either to open a lid or to use a built-in movable disc tray of the player for loading or unloading of a disc, which is inconvenient to use.
Moreover, conventional disc is not adapted for being slotted into the player. Such hinders the use of CD, VCD and DVD systems as portable items, and in particular not suitable for in-car entertainment application. Furthermore, existing CD, VCD and DVD players, in particular portable ones, make use of electronic arrangements for achieving shock-proof functions, which involves a complicated production process and will thus add to the manufacturing cost of the product.
It is thus an object of the present invention to provide a cartridge for an optically readable data carrier, an optically readable data carrier cartridge, and a player for such a cartridge with such a data carrier, in which the aforesaid shortcomings are mitigated or at least to provide a useful alternative to the public.
It is a further object of the present invention to provide a cartridge for an optically readable data carrier allowing easy insertion of the data carrier into a player, or easy retrieval of the data carrier from the player.
Summary of the Invention According to a first aspect of the present invention, there is provided a cartridge for an optically readable data carrier, including cover means for enclosing said data carrier and allowing said data carrier to rotate therein, characterized in including engagement means for engaging with said data carrier for simultaneous rotation.
According to a second aspect of the present invention, there is provided an optically readable data carrier cartridge including an optically readable data carrier enclosed in a cartridge, said cartridge including cover means enclosing said data carrier and allowing said data carrier to rotate therein, characterized in including engagement means engaged with said data carrier for simultaneous rotation. According to a third aspect of the present invention, there is provided an apparatus for playing an optically readable data carrier enclosed in a cartridge, including driving means for driving said data carrier into rotational movement, and means for emitting a light beam onto a data carrying region of said data carrier, characterized in that said driving means is adapted to
be in engagement with a side edge of at least part of said cartridge to drive said data carrier into rotational movement.
Brief Description of the Drawings Embodiments of the present invention will now be described, by way of examples only, with reference to the accompanying drawings, in which:
Fig. 1 is a front view of a cartridge according to the present invention;
Fig. 2 is a bottom view of the cartridge shown in Fig. 1;
Fig. 3 is a rear view of the cartridge shown in Fig. 1; Fig. 4 is a front view of the cartridge shown in Fig. 1 with the closure cover in an open position;
Fig. 5 is a rear review of the cartridge shown in Fig. 4;
Fig. 6 is a sectional view showing the interior of the cartridge shown in Fig. 1 taken along the line A-A in Fig. 2;
Fig. 7 is a sectional view showing the interior of the cartridge shown in Fig. 1 taken along the line B-B in Fig. 6
Fig. 8 is a front view of the bottom cover of the cartridge shown in Fig. 7;
Fig. 9 is an exploded view of the cartridge shown in Fig. 1;
Fig. 10 shows a side view of the disc-holder of the cartridge shown in Fig. 1;
Fig. 11 is a bottom view of the disc-holder shown in Fig. 10; Fig. 12 is a top view of a drive mechanism of a cartridge player according to a first embodiment of the present invention;
Fig. 13 is a side view of the drive mechanism shown in Fig. 12;
Fig. 14 shows schematically the operation of the drive mechanism shown in Fig. 12 on a cartridge; Fig. 15 is a side view of Fig. 14;
Fig. 16 is a top view of a drive mechanism of a cartridge player according to a second embodiment of the present invention; and
Fig. 17 a bottom view of the drive mechanism shown in Fig. 16. Detailed Description of the Preferred Embodiment Figs. 1 to 3 show respectively a front view, a bottom view and a rear view of a rectangular cartridge according to the present invention, generally designated as 10. The cartridge 10 includes a plastic top cover 12 and a plastic bottom cover 14 fixed with each other to define a
cavity for enclosing an optical disc (not shown in Figs. 1 to 3). In terms of dimension, the cartridge is of a length of 68mm, a width of 75mm and a thickness of 8mm. Given the compactness of the cartridge 10, such cartridges 10 are easily portable. Disposed along a top edge 16 of the cartridge 10 is a movable metal closure cover 18 which, when in the position as shown in Figs. 1 and 3, covers an opening 20 (see Fig. 5) in the bottom cover 14, to protect the optical disc enclosed in the cartridge 10 against accidental damage. When the closure cover 18 is moved to the position as shown in Figs. 4 and 5, the opening 20 is opened to expose the optical disc 22 to the outside environment. In particular, when the opening 20 is open, at least a sector of the data layer of the optical disc 22 is exposed so that the data stored in the disc 22 may be read. As the optical disc 22 can be rotated within and relative to the covers 12, 14, the entire data layer of the optical disc 22 may be exposed to the outside environment during rotation. When the closure cover 18 is in the position shown in Figs. 4 and 5, a peripheral edge of a disc-support (further details to be discussed below) is also exposed to the outside environment, for purpose to be discussed below. To prevent accidental damage to the optical disc 22, the closure cover 18 is biased, e.g. by a spring, to the position as shown in Figs. 1 and 3, to cover the opening 20.
The optical disc 22, say a VCD or DVD, is 60mm in diameter and is able to provide a storage capacity of 450MB, compared to 650MB of a standard 120 diameter disc. With the two layers register/writing technology now commonly used in the production of VCD movie discs, it is eventually possible for such a 60mm optical disc 22 to provide a storage capacity of 900MB, which should be sufficient for storing a standard movie of a playing time of around 100 minutes.
Fig. 6 shows a disc-holder, in the form of a circular plastic tray 24 of a thickness of 3mm positioned in the top cover 12, whereas Fig. 7 is a sectional view of the cartridge 10, showing the top cover 12, the bottom cover 14, the tray 24 and the disc 22. As shown more clearly in Fig. 8, the bottom cover 14 includes four rotatable lmm-diameter bearings 26a equi-distantly positioned along the circumference of a circle. As can be seen in Fig. 9, the top cover 12 also has four rotatable bearings 26b equi-distantly positioned along the circumference of a circle. The tray 24 has a recess 24a sized and configured to receive and engage the optical disc 22 for simultaneous rotational movement, e.g. by fixedly securing the optical disc 22 to the tray 24.
As also shown in Figs. 10 and 11, the tray 24 has a central metal post 30 for being received within the central hole of the optical disc 22. The upper end of the post 30 is received within a recess 32 (see Fig. 9) of the top cover 12, and the lower end of the post 30 is received within a recess 34 (see Fig. 9) of the bottom cover 14, thus allowing the tray 24, as well as the optical disc 22 engaged with it, to rotate relative to the rest of the cartridge 10 about the axis of the post 30.
When the top cover 12, the bottom cover 14, the tray 24 and the optical disc 22 are assembled, as shown in Fig. 7, the bearings 26b of the top cover 12 contact the top surface of the tray 24, whereas the bearings 26a of the bottom cover 14 contact the lower surface of the optical disc 22, thus firmly holding the optical disc 22 in the middle of the cartridge 10 for rotation. This feature will enhance both the smooth rotation of the optical disc 22 in the cartridge 10, and the capacity of the cartridge 10 to withstand internal flutter and any vibration from the outside. Such mechanical shock-proof mechanism is neat and tidy, and is significantly cheaper than electronic means adopted in the conventional VCD and/or DVD systems.
A first example of a drive mechanism of a cartridge player according to the present invention is shown in Figs. 12 and 13, and generally designated as 100. The drive mechanism 100 includes a motor 102 for driving a flywheel 104 into rotational movement, which extends partly above a platform 106 for receiving the cartridge 10 thereon. A laser emitter 108 is also caused to move along a slot 110 on the platform 106, thus allowing laser beam to be impinged upon the data layer of the optical disc 22 in the cartridge 10, for scanning and subsequent reception by a data reception device in the player.
Referring to Figs. 14 and 15, when the cartridge 10 is properly received, retained and aligned on the platform 106 of the drive mechanism 100, the closure cover 18 will be moved to the open position as shown in Figs. 4 and 5, in a manner similar to the movement of a closure cover of a conventional floppy disk in a floppy disk driver. When the closure cover 18 is in such a position, a peripheral side edge of the tray 24 is exposed to the outside environment, and is frictionally engaged by a rubber rim 112 of the flywheel 104 for rotation. In particular, when the flywheel 104 rotates in the anti-clockwise direction (in the sense as seen in Fig. 14), the tray
24, and thus the optical disc 22 engaged with it, will rotate in the clockwise direction, again in the sense as seen in Fig. 14, relative to the rest of the cartridge 10. It can be seen that the covers 12, 14, are stationary relative to the drive mechanism 100 during rotation of the tray 24 and the optical disc 22. When the optical disc 22 is caused to rotate, the laser emitter 108 will move along the slot 110 of the platform 106, to emit laser beam onto the optical disc 22, through the opening 20 of the cartridge 10.
A second example of drive mechanism of a cartridge player according to the present invention is shown in Figs. 16 and 17, and generally designated as 200. The drive mechanism 200 also has a motor 202 for driving a flywheel 204, which extends partly above a platform 206. In this drive mechanism 200, a separate motor 208 is provided for driving a laser emitter 210. An eject key 212 is provided for actuating a mechanism to release, e.g. pop-out, the cartridge 10 from the drive mechanism 200. It can be seen that the above describes a compact optically readable data carrier cartridge and a player system which are easy to manufacture and operate. As the conventional movable disc drawer is now dispensed with, such a system can be of palm-sized or for in-car use. It is also possible to provide a slot in the player into which a cartridge 10 according to the present invention may be inserted, so as to allow the optical disc 22 in the cartridge 10 to be driven by a drive mechanism 100, 200 in the player for playing the optical disc 22.
It should be understood that the above only illustrates examples whereby the present invention may be carried out, and that various modifications and/or alterations may be made thereto without departing from the spirit of the invention.
It should also be understood that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any appropriate sub-combinations.