CA2481734A1 - High density disc storage apparatus - Google Patents

Abstract

An arrangement is provided which allows data storage discs such as CDs or DVDs, to be added to or retrieved from a storage magazine which stores discs at high storage densities. Within the disc storage magazine, access to each disc storage position is achieved. Each disc is retained in its storage position by a slot in the bottom of the magazine and a spring finger on top. A belt drive overhead, in conjunction with a disc lifter at the bottom, both of which are permanently aligned with an entry/exit gate at the front of the apparatus, effect movement of a disc from or to its storage position. This disc movement may be directed to add or retrieve discs to the disc storage magazine from outside the apparatus, or may be directed to a module inside the apparatus which may read or write to the disc.

Description

<:IELD OF THE INVENTION
This invention relates to an apparatus designed to store discs, mainly data carrier discs such as CDs and DVDs.
Due to the susceptibility of data storage discs to get scratched and thereby be compromised in their function, it is advisable to store the discs' so that their surtace cannot easily get scratched or otherwise damaged. The deed to reduce the potential for damage to the data storage discs and limit manual handling of the discs, has brought about products which store a limited number of discs, and allow the user to select a particular disc, or even a subsection on the disc, and have the built-in player play back what is recorded on the disc. Such arrangements are commercially available to store a few hundred CDs or DVDs. They combine protection, space efficient archival, and handling convenience for playback purposes.
Another aspect of disc storage is to keep them safe from unauthorized access, such as theft. This aspect is particularly relevant in the movie rental business.
The invention described below seeks to advance the state of the art towards an increase in disc storage density and improvements in the ease of use in a disc rentallsales environment.
BACKGROUND OF THE INVENTION
Quite often data carrying media are in disc form. Records, CDs, and DVDs are some examples. Typically one or both sides of such discs are susceptible to damage from mechanical abrasion or deformation, which could easily interfere with the quality of the stored data. Limiting access to an ensemble of CDs or similar discs to only authorized persons, that are entrusted in handling them properly, is one of many motives for secure storage of such discs. Others include theft prevention and tamper proofing.
Mostly random access to a selection of discs among a large number of archived ones is required. One example is the jukebox which debuted in the era of records.
Here one record from the ensemble is chosen, retrieved from its storage position, its contents getting played back, and the record then stored into its old storage position or a newly selected one.
The general jukebox concept has been extended to CDs and DVDs in various forms. Among other versions, the industry offers one which stores discs on a carousel. Adding to and removing discs from the carousel is done mostly manually.
Selecting a disc through a human/machine interface leads to the carousel spinning until the chosen disc is lined up with a read (or record) mechanism. Grip arms or shifters translate the disc to the read (write) module. The read (write) module typically spins the disc and a read (write) head finds or records information on associated tracks on the disc. Once complete the spinning of the disc is halted and the disc is transferred back to its storage position by the same grip arms or shifters that handled the translafiional movement of the disc earlier.
A common problem to which a number of solutions have been proposed and implemented, is how to resolve the conflict between reliably retaining discs (static) in their storage position on one side, and reliably moving (dynamic) the discs into and out of their storage positions. This problem becomes pronounced when the space between adjacent discs becomes very small, as is the case when the disc density increases in favour of storing many discs in a small volume. It is then that the grip arms might either not fit in between adjacent discs, or they might scratch the surface of the discs.
SUMMARY OF THE INVENTION
DESCRIPTION OF THE PRIOR ART
The pursuit of providing disc storage solutions with random access to any disc, particularly when the disc storage base is arranged in carousel form, uses one of two principal arrangements to stabilize the position of any given disc in its position.
One typical solution provides extensive separation ~nralls between adjacent discs, erected on a common base plate, as described in U.S. Patent 4,750,160.
Another typical solution holds each disc between tracks in corresponding slots established in opposed carrier plates which are app. one disc diameter apart, as described in U.S. Patent 5,067,116.
In both cases, and derivations thereof, the space left between adjacent discs is in the order of the thickness of one disc or larger, due to grippers or shifters that must form fittingly engage with the disc when seeking to translate it in and out of its storage position. If disc storage density is to increase further other arrangements must be found to shrink the space between discs by an additional amount, yet _4_ without much increased risk of damaging the data surface.
DESCRIPTION OF THE INVENTION
It is the objective of this invention to significantly increase, i.e. double, the disc storage density over arrangements as described above. To achieve this increase in density, the movements required to select a disc 'from the ensemble have been split in two trajectories; inserting and dropping andlor lifting and ejecting.
Trajectory one positions the desired disc on its storage position in the x-y plane, the plane of the base plate, in x-direction, between a lifter arm below the disc and a belt drive mechanism above the disc. Lifter arm and belt drive mechanism are opposed and typically stationary with respect to the chassis of the overall storage device. They are also aligned with an entry/exit slot, andlor a playback subassembly. The lifter arm effects trajectory two, which lifts the disc in z-direction, which is perpendicular to the x-y direction, until it makes contact with the moving belt of the belt drive mechanism. The friction force between the belt surface and the disc surface on one side, and disc surface and base surface on the other side creates a tangential force on the disc, which in turn produces the torque that rolls the disc in or out of its storage position in y-direction, which is the direction of the moving belt.
The advantage of this general arrangement is that a simple slot in the base plate of the disc storage, combined with an overhead spring finger per disc storage position, is sufficient to hold discs in their storage position. The slots and associated spring fingers can be practically as narrow as the width of a disc.
In a preferred embodiment of this general arrangement the discs are oriented radially on a carousel. Now the storage density of discs can be increased to the extreme point where the discs' edges pointing towards the center of the carousel may even touch. This is possible due to the fact that the data area typically excludes a small annular section from the perimeter of the discs towards the center.

The invention is described in more detail below, whereby a preferred embodiment, using a carousel to store the discs, serves to illustrate the principles.
Different configurations, such as a linear slide onto which the discs are positioned, are possible. Therefore, what is described as preferred embodiment serves to explain the principle, and is not to be interpreted as limiting the scope of the invention to this one configuration.
Overall, the main use, but not only use, of the invention will be to allow retailers specializing in the selling or renting of Records, CDs and DVD to store the Records, CDs and DVD in the High Density Disc Storage Apparatus behind the sales counter to be accessed by the customer on request for purchase or rent.
The end result will be a reduction in the amount of stolen Records, CDs and DVD
from the said retailers since the Records, CDs and DVD are not directly accessed by the consumer. In turn, the retailers' shrinkage will be reduced.
In pursuit of this description several drawings are furnished.
DESCRIPTION OF THE DRAVNINGS
The drawings show the functional elements of a preferred embodiment of the invention. Other embodiments are possible and what is shown in the drawings and the following description is meant not to limit the extent of the underlying principles.
A detailed narrative description of the preferred embodiment follows further below and references the same drawings.
To serve clarity directional conventions are used. A Cartesian coordinate system with axis' x, y, and z, which are perpendicular to each other, is meant to be aligned so that the base plate of the apparatus is aligned with the x-y direction (Fig.1 ) The rotational axis of the carousel is aligned with the z-direction. To facilitate in the functional description of the apparatus the general x-direction has been supplemented with directions 100 and 101, the y-direction with 200 and 201, and the z-direction with 300 and 301.
Fig.1 shows the plan view looking into a high density disc storage device according to the spirit of the invention. Fig.2 below shows a corresponding front view.
In the center of the apparatus is disc storage carousel 1, on which, for the purposes of illustration, just two discs 2a and 2b are shown in their positions as stored. If all disc storage positions were occupied, which in an apparatus measuring perhaps 24 inch by 24 inch could be for 1000 discs, neighbouring discs would touch at the points closest to the center of the carousel.
The carousel can rotate around rotational axis 302 in such a way as to bring any disc storage position on the carousel into alignment with the entry/exit gate 3 in the front wall 4 of the chassis. The rotational movement of the carousel is effected by motor 5 coupled to first pulley 6. Transmission link 7, a belt or chain, drives second pulley 8, which is coupled to pinion 9. Pinion 9 meshes with a circular rack rigidly connected to carousel 1. The axis of rollers 11 a, 11 b, and 11 c are fixed to the chassis bottom 12 and maintain the position 302 of the center of carousel 1.
Rollers 11 a and 11 b in particular provide the reaction force against the belt or chain tension force from transmission link 7. Rollers 13a, 13b, and 13c, with their respective axis rigidly connected to chassis bottom 12, serve to support the weight of carousel 1, which acts in direction 301, allowing carousel 1, however, to rotate with minimal friction force.
Each disc storage position on carousel 1 is defined by a narrow slot in the bottom of carousel 1 (not shown in Fig. 1 due to the small scale,' but illustrated in detail in Fig.4), just wide enough for a disc to fit in without interference. Above each slot is a spring finger, shown in Fig. 1 for the two discs 2a and 2b and 14a and 14b respectively. A full set of spring fingers forms an annular ring fastened to carousel wall 15, whereby radial cuts extending radially outward beyond the immediate vicinity of carousel wall 15 separate each spring finger from its neighbour (illustrated in larger scale in Fig.S) .
Aligned with the entrylexit gate 3 is a lifter blade 20 affixed to a lifter arm 21.
Movement of the lifter blade 20 in direction 300, pushing through the slot above in carousel 1 will lift a disc - if present - in the same direction. Lifter arm 21 pivots around pivot pin 22, which is supported by pivot supports 23a and 23b.Pivot supports 23a and 23b are affixed to the chassis bottom 12. A crank pin 25 engages in a slot in that portion of lifter arm 21 which is located towards the center of the carousel 302 beyond pivot pin 25. Crank pin 25 is fastened to crank disc 24, which rotates when driven by motor 26a via gearhead 26b, causing lifter arm 21 to swing in directions 300 and 301. (Fig.6 and Fig. 7 provide details at a larger scale) A belt 30 is wrapped around idler pulleys 33a, 33b, and drive pulley 31. ~rive pulley 31 sits on the output shaft of gearhead 32a, driven by motor 32b. This pulley and motor arrangement is mounted to sideplates 34a and 34b, and may, as an assembly, slide in directions 300 and 301 via bearings 35a and 35b. Bearings 35 a and 35b themselves are affixed to chassis front wall 4.
Projecting in direction 301 from the chassis bottom 12 are stacking pins 40a, 40b, 40c, and 40d, which locate, and facilitate to secure, multiple disc storage apparatuses stacked above each other.
Fig. 3 shows a section cut (400-400 per Fig.1) to illustrate the disc retention, disc lifting, and disc loading and unloading mechanism.
Carousel bottom 1 is shaped on its underside with recess 1a, to which circular rack is rigidly connected. Pinion 9, as part of the drive train to spin the carousel, is _g_ shown isolated for purposes of clarity, not showing pulleys 6 and 8, belt 7, and motor 5 as described in Fig.1.
Disc 2 is shown seated in slot 1 b, with spring finger 14 pushing down, causing the disc to be retained in its position, even under the influence of acceleration from repositioning the carousel, and a reasonable amount of vibration and shock exerted onto the apparatus from the outside.
When discs are to be loaded from the outside of the apparatus into one of the storage positions on the carousel, they pass through the entrylexit gate 3 in front wall 4. Aligned with entryJexit gate 3 is lifter blade 20, mounted onto lifter arm 21.
The latter pivots around the axis of lifter arm pivot pin 22, which is supported by lifter support brackets 23a and 23b, both of which are fixed to bottom chassis plate 12.
The end of lifter arm 21 pointing towards front wall 4 engages with rocker arm 42.
A rocker arm support 44 with rocker arm pivot pin 43 allows a teeter-totter movement of rocker arm 42, which in turn causes up and down movement of push rod 41.
Push rod 41 acts to effect an up and down movement of the drive belt assembly, comprising, among other elements, belt 36, idler pulleys 33a and 33b, drive pulley 31, and motor 32a with gearhead 32b. This drive belt assembly is movably constrained to only move freely in lateral directions 3001301, and not any other direction. Responsible for this are bearings 35a and 35b.
Spring 40 exerts a force onto the drive belt assembly in direction 301, which is reacted by spring seat 39, which in turn is attached to front wall 4. Drive belt assembly height stop 38, fixed against the chassis bottom 12 regarding its position in direction 300 and 301, in conjunction with adjustment screw 37, which adjustably _g_ limits the travel of the belt drive assembly in direction 301.
Fig.4 shows by way of a cutaway section 500-500 (Fig.3) part of carousel 1 and its immediate vicinity at a larger scale. To illustrate the principle in the drawings more clearly the possible disc storage density has been reduced, and thereby the disc storage positions are tangentially spaced much farther apart than a high density arrangement could allow. Also, the belt drive assembly and push rod arrangement are not shown in Fig. 4, for the same reason of focusing with this drawing on just clarifying the principle of disc retention.
Every disc storage position is characterized by a slot 1 b in carousel bottom 1 and an associated track groove 1c which extends radially to the perimeter of carousel bottom 1. At the entrylexit gate shelf 4a, one track groove 4b is position ally aligned with centerline 310 (Fig.2) of entry/exit slot 3, further position ally aligned in direction 300 and 301 with the track grooves 1 c on the carousel, and directionally aligned with the connecting line from carousel rotational axis 302 (Fig.) to the centerline 310 (Fig.) of entrylexit slot 3.
Lifter blade 20 is removably affixed to lifter arm 21 with fastening elements (such as screws) 20a and 20b. Lifter arm 21 is not shown in its full length beyond its pivot point. The pivot point of lifter arm 21 is formed by pivot pin 22, which is supported against the chassis bottom 12 (Fig. 3) by lifter supports 23a and 23b, each of which is affixed to chassis bottom 12 with suitable means, i.e. screws 23c.
Lifter arm 21 is supported in the area below disc storage slots 1 b against movement in direction 100 by alignment block 27b. Alignment block 27b preferably is fixed against chassis bottom 12 (Fig.3). A corresponding alignment block 27a limits movement of lifter arm 21 with lifter blade 20 in direction 101.
Provisions to adjust the amount of clearance between lifter arm 21 and alignment block 27 on one side, and lifter blade 20 and corresponding alignment block 27a on the other side are shown in the form of slot 28 and screw and washer combination 29.
This allows limited movement of corresponding alignment block 27a in directions 100 and 101.
The location of circular rack 10 is indicated to show it is radially not interfering with the disc storage slots 1 b, and laterally not interfering with track grooves 1 c as rack is located in direction 301 (Fig. 2) on the underside of carousel 1.
Fig 5. serves to illustrate the spring finger assembly and shows particulars in a top view as a larger scale cutaway section of Fig1. in direction 600-600 per Fig.3.
The spring finger assembly comprises an annular center section 14 and a plurality of extremities 14a. Each extremity 14a is aligned with a disc storage slot 1 b.
The spring finger ensemble 14 is rigidly connected to carousel wall 15 with fastening elements 16. Fastening element 16 can be a screw as shown, or a form fitting snap fit, pressure fit, or otherwise.
To establish a reference to the rest of the apparatus, part of the lifter arm 21, lifter blade 20, pivot pin 22, supports 23a and 23b are shown, as well as part of front wall 4 with front wall shelf 4a, and entrylexit gate 3.
Fig. 6 shows a view onto the lifter drive mechanism in direction 200, and Fig.
7 an associated view onto the lifter drive mechanism in direction 101. The lifter drive mechanism comprises motor 26a, motor gearhead 26b, gear output shaft 26c, crank disc 24 with crank pin 25, which engages in lifter arm slot 21a of lifter arm 21.
Further to this, 2 sensors 50 and 51 are shown, by means of which the position of the lifter arm can be determined by an electronic controller. These sensors can be electromechanical, such as switches, electro-optical such as opto-switches, inductive or other types.
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DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of the invention as illustrated in the drawings described earlier, may measure approximately 24 by 24 inches square by 7 inches high, and store around 1000 discs such as CDs or DVDs. Several of these high density disc storage devices may get stacked upon each other, forming a tower, which, on relatively small footprint, and with moderate height, could provide convenient and secure storage of a sizeable inventory of CDs or DVDs.
For the purpose of reliable and secure fastening of multiple high density disc storage devices in the form of a tower, one such application is to have each apparatus comprised of a plurality of feet 40 per Fig.1 and Fig.2 projecting from the bottom 12, which can engage in correspondingly located cavities of another device below, preventing lateral movement of the devices against each other in directions 100 and 101 and directions 200 and 201. To prevent separating units from each other when stacked, which equals movement in directions 300 and 301 of one or the other apparatus, feet 40 may be equipped with means to block such movement. This can i.e. be accomplished by an annular indentation in feet 40 of a first storage device, which may engage with keyhole slots in lock tongues established in the second device.
An electronic controller in each high density disc storage device may receive the command to retrieve a stored disc through an interface such as keyboard, data link to a computer, or otherwise. Integration with a local database which associates the bar code andlor other information such as title, colour or signature, will facilitate the process. The command to accept a disc for storage could be conveyed through the same or a second interface of similar nature. The controller's task is to act upon any such command by stimulating electromechanical devices such as motors, solenoids, etc., inside the high density disc storage apparatus, considering the input from various sensors, and acting from algorithms stored in its memory.
Such controllers are well known to those skilled in the art.
Upon receiving the command to store a disc, the controller will determine the present inventory of stored discs and seek empty storage positions on carousel 1.
While it appears principally possible to store the arriving disc at any free location on the carousel, there may be considerations such as weight distribution, shortest time to store, most likely shortest time to retrieve, etc. that lead to the choice of a particular storage position.
Once the actual storage position that the newly arriving disc is to be stored on has been determined, according to the algorithms that are implemented in the controller, it is advisable that the controller checks the position of lifter arm 21. This can be accomplished by reading sensors 50 and 51. In case that lifter blade 20 is engaged in a carousel slot 1 b, this would be indicated by (opto) sensor 51 being asserted, (i.e. a fight beam of the sensor being interrupted by the edge of lifter arm 21 per Fig.7). To avoid damage to the lifter arm mechanism, the controller would activate lifter motor 26a until the combination of sensors 50 and 51 would indicate that the lifter blade 20 is free from engagement with slot 1 b in carousel 1.
The actuation of the lifter blade 20 through lifter arm 21 is effected by the output shaft 26c of the gearhead 26b driving crank disc 24, which has crank pin 25 rigidly attached at a radial offset with respect to output shaft 26c. Crank pin 25 slides in slot 21a of the lifter arm 21. Rotation of crank disc 24 will therefore cause a teeter-totter movement of lifter arm 21 around its pivot point established by the location of pivot shaft 22.
Once established that there is no undue engagement of lifter blade 20 with any of the carousel slots 1 b, carousel 1 can rotate around rotational axis 302 in such a way as to bring any disc storage position on the carousel into alignment with the entry/exit gate 3 in the front wall 4 of the chassis. The rotational movement of the carousel is effected by the controller sending an appropriate signal to energize motor 5, which is coupled to first pulley 6. Transmission link 7, a belt or chain, drives second pulley 8, which is coupled to pinion 9. Pinion 9 meshes with a circular rack 10 rigidly connected to carousel 1.
For those skilled in the art it is obvious that means must exist which tell the controller the actual position of any of the carousel's storage locations with respect to the entrylexit gate 3. Such means can i.e. include absolute encoding marks along the circumference of carouse! 1 which can get read by a sensor remaining fixed against chassis bottom plate 12 of the apparatus. Other possibilities include an incremental encoder attached to the shaft of motor 5 in combination with a home sensor that reads a reference mark attached to carousel 1 once per revolution of carousel 1. Yet other possibilities include synchro resolvers as sensors able to provide a feedback signal to the controller about the angular position of carousel 1 with respect to a fixed reference of the chassis such as entry/exit slot 3.
The axis of rollers 11 a, 11 b, and 11 c are fixed to the chassis bottom 12 and maintain the position 302 of the center of carousel 1. Rollers 11 a and 11 b in particular provide the reaction force against the belt or chain tension force from transmission link 7. Rollers 13a, 13b, and 13c, with their respective axis rigidly connected to chassis bottom 12, serve to support 'the weight of carousel 1, which acts in direction 301, allowing carousel 1, however, to rotate with minimal friction force until the desired storage slot is aligned with the entry/exit gate 3 in front wall 4.
Free rotational movement of carouse( 1 is now, with lifter blade 20 being disengaged from slot 1b in carousel 1, also possible, because the belt drive assembly above the entry/exit slot (partly comprising belt drive motor 32b, associated gearhead 32a, drive pulley 31, idler pulleys 33a and 33b, side walls 32a and 32b, belt 30 and belt pressure plate 36) has been pushed up in direction via push rod 47, rocker arm 42, and the engagement with lifter arm 21 (Fig.3) Once the desired storage position 1 b is lined up with the entry/exit gate 3 the controller will activate lifter motor 26a until the lifter blade 20 is engaged with storage slot 1 b and is in its top position. The top edge of lifter blade 20 is now horizontally aligned with the bottom of track groove 1c, which in turn is aligned with track groove 4b in front wall shelf 4a.
Commensurate with lifter blade moving up (direction 300) the belt drive assembly moved down, activated through lifter arm 21, rocker arm 42, push rod 41, and the spring force exerted by spring 40, until this movement is stopped by adjustment screw 37 touching stop 38. This leaves the lower, horizontally oriented portion of belt 30, which is backed by backing plate 36, at a small distance above the edge of a disc 2, if one was in fact seated in its storage position. However, for the case being described over the past paragraphs, namely accepting a disc from the outside into storage in the high density disc storage apparatus, it is assumed though that the disc storage position just below drive belt 30 is empty.
Referring to Fig.1 the adjustment criteria for adjustment screw 37 will be clarified further, describing temporarily the situation of a disc 2 being seated in its storage position on carousel 1. While the carousel spins around its center 302 (Fig.1) disc 2 experiences centrifugal forces and gravitational force. Apart from these systematic forces vibration and shock forces from surrounding apparatus and general handling can be expected to randomly occur as well. To maintain disc 2 upright in its storage slot 1 b, spring finger 14a exerts a downward force onto disc 2 at contact point 810. This downward force may be in the order of 0.05N to 1.SN, vis a vis the weight of a disc which is perhaps 0.15N. An upper limit for the force acting on disc 2 at point 810, exerted by spring finger 14a pressing onto disc 2 at point 810, which is being reacted by carousel 1 at contact points 830 and 840, is given by the stiffness of disc 2 against buckling. Buckling of disc 2, so that there is the possibility of rubbing against the next neighboring disc, with the prospect of damage to the data surface, is typically undesirable. If the spring force of spring finger 14a approaches the lower end of the range the susceptibility of disc 2 getting dislodged from its seat in slot 1 b increases and undermines practical functioning of the apparatus. Another important geometrical relationship between the tip of spring finger 14a and slot 1b comes from the requirement that the spring force from spring finger 14a is directed so as fio press disc 2 into slot 1 b and not out of it. For this to be effected point 820, which is the cross point between a line from spring finger 14a contact point 810 through the center 800 of disc 2 and beyond, and the perimeter of disc 2, must laterally (direction 200 and direction 201) be within slot 1b. As indicated in Fig.3, the position of idler pulley 33b in directions 200 and 201 assures that when lifter blade 20 pushes disc 2 up in direction 300, the portion of belt 30 which is in line with directions 200 and 201, and which is coplanar with the upper surface of carousel 1, contacts the perimeter of disc 2 at contact point tangentially. The space between the underside of belt 30 and to tap of disc 2, namely the prospective contact point 850, in the case that disc 2 is seated in slot 1 b and contacts carousel 1 at points 830 and 840, should be smaller than the height which disc 2 can get lifted by lifter blade 20, so as to assure maximum friction force between belt 30 and disc 2 at contact point 850. This friction force is the product of friction coefficient for the material pair beltldisc and normal force from the belt drive at contact point 850. The normal force at contact point 850 is generally the sum of a gravitational force component and the spring force from spring 40. Otherwise, it is advisable to establish a gap between belt 30 and disc 2 at prospective contact point 850, by i.e. appropriately setting adjustment screw 37, when disc 2 is seated and contacts carousel 1 at points 830 and 840, so that the belt surface is not in danger of touching neighbouring discs except the one centered below belt 30, which is also aligned with entry/exit gate 3.
In continuation of describing the acceptance of a new disc 2 into a selected storage position on carouse! 1, it is now, after the lifter blade 20 has been moved to its top position, assumed that the controller sends an appropriate signal to the motor 32b of the belt drive, so that the belt side facing carousel 1, which is backed by backing plate 36, moves towards the rotational axis 302 of the carousel, which, per drawing Fig. 3 would coincide with direction 200. A user of the apparatus, perhaps being made aware of the readiness to accept the disc for storage by the controller issuing an acoustical or optical signal on the front by way of a sonalert or light, can now slide the disc to be stored into entrylexit gate 3 until the disc gets gripped by the belt, and subsequently rolled in direction 200, guided first by track 4b in front wall shelf 4a and then by track 1c in the top surface of carousel 1 until disc 2 has reached its final position when its movement gets blocked by wall 15.
To ascertain proper tracking of the disc 2 while being translated into and out of its storage position, tracks 1 c and 4b may be complemented by guide plates affixed to side walls 34a and 34b just below belt 30.
Once disc 2 has reached its final position, fiypically being stopped by wall 15, which may also get sensed by i.e. optical sensors 60a and 60b mounted at the front wall 4 , the controller stops belt drive motor 32b, and sends a signal to lifter motor 26a to effect lowering lifter blade 20 to its lower rest position. As a result, and as the belt has moved disc 2 under spring finger 14a, which is now exerting force towards carousel 1, disc 2 is held form fittingly in storage slot 1 b and by way of friction fit from spring finger 14a at contact point 810 in its such defined storage position.
Commensurate with lowering lifter blade 20 the belt drive assembly has been lifted up and away from possible interference with any discs stared on carousel 1, which clears the way for subsequently rotating carousel 1to a different storage position in the manner already described.
Retrieving any stored disc 2 from a given storage position follows essentially the spirit and movements described, with some directions reversed. In essence, it again is first assured that lifter blade 20 is disengaged from any slot 1 b in carousel 1, then carousel 1 is rotated by the drive train including motor 5 'to have the selected storage position lined up with the entrylexit gate 3, belt drive motor 26a is turned on to have belt 30 move in the section backed by backing plate 36 towards the entry/exit gate 3, and lifter motor 26a is commanded to move lifter blade 20 to its top position. Once the so lifted disc 2 contacts belt 30 at contact point 850, disc 2 rolls, guided in tracks 1 c and 4b, and perhaps additional guide plates around the belt, out of entrylexit gate 3. Signals from sensors 60a and 60b, which could be of optical curtain type, may be used to stop the movement of belt 30 before disc disengages from the constraint between track 4b and belt 30 and possibly falls uncontrolled out of the apparatus.
CONCLUSION
The problem of increasing the storage density of traditional disc storage devices has been solved by breaking the trajectory of moving discs from the entry/exit gate of the apparatus into a determined storage position, and conversely, moving a disc from its determined storage position to the entrylexit gate, up into two consecutive trajectories each of which is perpendicular to the other, and using selective friction force from a belt drive mechanism to avoid any gripper or shifter to take up space between adjacent discs.

Claims (9)

1. a disc storage device with an insertion/retrieval mechanism that only engages the edge of each data/storage disc, such as CDs or DVDs, allowing the said data/storage discs to be housed in a storage magazine in close proximity to each other;

2. an apparatus, as defined in claim 1, which holds a data/storage disc in place in the storage magazine using a slot in the bottom of the storage magazine below the data/storage disc and a spring finger on the top of the data/storage disc;

3. an apparatus, as defined in claim 1, which has a belt drive overhead, in conjunction with a disc lifer at the bottom, both which are permanently allied with an entry/exit gate at the front of the apparatus, effecting movement of a disc from or to its storage position;

4. an apparatus, as defined in claim 1, which has a circular carousel together with touching at the back edge and an ejector mechanism;

5. an apparatus, as defined in claim 1, which allows expandability such as multiple units involving carousels that can be stacked together allowing for discs to be retrieved from the disc storage magazines outside the apparatus;

6. an apparatus, as defined in claim 1, which contains a carousel which can be lifted out of its holding position such as to allow manual removal of discs which have been incorrectly positioned or jammed within the carousel;

7. an apparatus, as defined in claim 1, increasing the storage density of traditional disc storage devices by breaking up the path to move a data/storage disc from the entry/exit gate to its determined storage position into consecutive trajectories each of which is generally perpendicular to the other, and by using selective friction force from a belt drive mechanism to avoid any gripper or shifter to take up space between adjacent discs;

8. an apparatus, as defined in claim 1, which has a misfiling prevention system which interfaces a computer system and bar code reader to ensure discs that are added or retrieved to the disc storage magazines from outside the apparatus are stored in the correct location; and.

9. an apparatus, as defined in claim 1, which allows an interface between a computer system and/or bar code reader allowing data/storage discs to be added or retrieved from the disc storage magazine and moved either into the disc storage magazine or inside the apparatus electronically.