Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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CAL FIELD
This invention relates to an automatic disc
handling system and method for retrieving and
positioning information carrying discs between a
storage position to a position of use, and wherein the
system includes a robot which is controlled by a
computer and a robot controller operated by demand
signals fed to the computer from a remote station
occupied by a user person.
BACKGROUND ART
Various information carrying disc handling
systems are known, such as disclosed in U.S. Patent
4,286,790 which relates to an optical disc changer
apparatus. This apparatus is capable of moving
information carrying discs from storage positions to
playback apparatus. The apparatus can also contain a
plurality of these optical discs having a very large
capacity of data stored thereon. The system utilizes
a carriage having at least two positioning an
retracting carriers. Gripping means is coupled to the
carriers to grip a protective cartridge having an
optical disc enclosed therein. The apparatus
accordingly handles cartridges and not discs. The
cartridges are also stored along a vertical storage
position within the housing, such as a playback
device, and therefore has limited storage capacity.
Various laser disc players are also known, and
employ magazines for storing a plurality of discs for
listening to audio information stored on these discs
in a selected order. Usually these players can handle
anywhere from two to five discs which are loaded
therein by hand. Examples of such devices are
disclosed, for example, in U.S. Patents 4,797,865 and
5,103,437. However, in these patents it can be seen
that the discs are stacked in a horizontal manner
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immediately adjacent a disc reading device, and all
located within a small compact housing.
Optical disc handling systems wherein discs are
stored in horizontal fashion in cabinets are disclosed
S in U.S. patents 4,040,159 and 4,989,191 as examples
thereof. A plurality of horizontal cases are
superposed one on top of the other, and a robotic
means is used to transfer these discs towards a
playback device that may be integrated with the
system. However, such devices have various drawbacks
and the storage of discs is not easily expandable.
SUMMARY OF INVENTION
The present invention relates to an improved
automatic disc handling system capable of storing
thousands of discs and transferring them to various
locations while keeping data on their location.
It is a feature of the present invention to
provide an automatic disc handling system and method
for retrieving and positioning information carrying
discs, such as video discs, between a storage position
where several discs are stacked closely spaced in
horizontal stacks and positioned in drawers which are
retractable by robot means, and wherein a disc is
picked up and transferred to a position of use where
it is placed in a playback device.
Another feature of the present invention is to
provide an automatic disc handling system and method
wherein a disc may be retrieved from a playback device
and positioned in any of a plurality of storage
drawers for storage.
Another feature of the present invention is to
provide an automatic disc handling system and method
for retrieving a disc from a playback device and
wherein the disc is automatically inverted and
repositioned in the playback device or a storage
drawer.
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Another feature of the present invention is to
provide an automatic disc handling system and method
for retrieving and positioning information carrying
discs between a storage position to a position of use,
and wherein the storage position is easily expandable.
Another feature of the present invention is to
provide an automatic disc handling system and method
for retrieving and positioning information carrying
discs between a storage position to a position of use
wherein a plurality of playback units are provided,
and wherein said system utilizes a single robot having
a pair of robotic arms and capable of handling two
information carrying discs simultaneously for playback
and/or storage.
Another feature of the present invention is to
provide an automatic disc handling system and method
for retrieving and positioning information carrying
discs between a storage position to a position of use
wherein the storage position is comprised of a
plurality of horizontally disposed trays superposed in
a dense compact position in frames disposed vertically
along an arc of a circle and to each side of a
plurality of playback unit stations which is also
positioned on the arc with a robot being disposed at
the center of the arc and acts as a server.
Another feature of the present invention is to
provide an automatic disc handling system and method
for retrieving and positioning video information
carrying discs between a storage position to a
selected one of a plurality of playback units at a
position of use, and wherein said discs are selected
by a user person, at a remote station, and sending
demand signals to a computer connected to a robot
controller who controls a robot which is instructed to
retrieve a requested video information carrying disc
for playback to the remote station occupied by the
user person.
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According to the above features, from a broad
aspect, the present invention provides an
automatic disc handling system for retrieving and
positioning information carrying discs between a
storage means to a position of use where there is
provided one or more disc information retrieving
devices operated by end user command. The system
comprises robot means having a pair of robotic
arms. Each of the arms has actuable engaging
means for engaging and disengaging one of the
discs. Storage means is also provided and has a
plurality of superposed sliding trays containing
one or more disc retaining cavities on a top
surface thereof. The sliding trays have
engageable means for the displacement of the trays
from the storage position to a retracted loading
or unloading position. The robotic arms of the
robot means has tray engaging means for engaging
the engageable means of a selected one of the
trays to displace same from the storage position
to the loading and unloading position and back to
the storage position. Control means is provided
to cause the robot means to move to a selected
position and cause one of the robotic arms to
engage a selected one of the disc at a selected
location at the storage position or position of
use and to effect a specific work function. The
pair of robotic arms are individually controllable
pivotal arms. The arms each have a picker
mechanism at a free end thereof. The picker
mechanism engages a disc for displacement and
release of the disc at a desired location. The
pair of pivotal arms are pivotally connected to
the robot means for simultaneous movement about a
respective pivot connection. The control means
controls the pivoting of the arms to cause the
disc engaged by the mechanism of one of the arms
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to be transferred to the picker mechanism of the
other arm to invert the disc.
According to a still further broad aspect of
the present invention, there is provided a method
of automatically retrieving and positioning
information carrying discs between a storage
position where the discs are stored on a plurality
of horizontally disposed sliding trays stacked in
vertical columns to a position of use in a disc
playback unit. The method comprises the steps of
identifying a disc to be retrieved and to be
positioned in the playback unit. A robot having a
pair of robotic arms is displaced to a position
where the disc identified is located. Each
robotic arm has a picker mechanism at a free end
thereof. The disc is caused to be positioned to a
retrievable position. One of the robotic arms is
displaced to a disc engaging position to align one
of the picker mechanism of the arm above the disc.
Disc aperture engaging fingers are positioned
through the engaging aperture. The aperture
engaging fingers are actuated to move from a
retracted position to a an expanded disc engaging
position. The engaging fingers are retracted to
displace the disc in clamping engagement between
the fingers and abutment means on a top surface of
the disc adjacent the aperture. The picker
mechanism is caused to engage the disc and the
robot is moved to the playback unit. The arms are
pivoted to cause the disc engaged by one of the
picker mechanism to be transferred to the picker
mechanism of the other arm to insert the disc when
required and the disc is released on a support
base of the playback unit.
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BRIEF DESCRIPTION OF DRAWINGS
A preferred embodiment of the present invention
will now be described with reference to the
accompanying drawings in which:
FIGURE l is a perspective view of the automatic
disc handling system for retrieving and positioning
information carrying discs by robot between storage
positions to a position of use;
FIGURE 2 is a block diagram showing the system
of the present invention;
FIGURE 3 is a front view showing the
construction of the pair of robotic arms secured to the
head of the robot, and wherein an information carrying
disc is held by each of the arms;
FIGURE 4 is a side view of Figure 3;
FIGURE 5A is a perspective view showing the
construction of a vertical storage frame in which
sliding trays are secured;
FIGURE 5B is a perspective view showing an
alternative construction of the engageable means
for
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engaging and pulling the trays from the storage
frames;
FIGURE 6A is a fragmented top view showing the
engageable aperture formed in the front edge of the
sliding tray, and the finger element of the robot
which engages with the aperture;
FIGURE 6B is a view similar to Figure 6A, but
showing the engaging finger element moved to an
engaging position;
FIGURE 6C is a top view showing a sliding tray
having a single disc stored thereon, and illustrating
the position of the engageable aperture of a tray
positioned thereunder;
FIGURE 7 is a top view of the robot with a
robotic arm disposed over a disc loading and unloading
position of the tray and adjacent a plurality of
vertical storage frames;
FIGURES 8A to 8D are simplified side views
showing the operation of a gripper mechanism for
engaging in the disc engaging aperture of an
information carrying disc to remove same from its
sliding tray;
FIGURE 9A is a front view showing a pair of
robotic arms with one arm having a disc before
transferring the disc to the other one of the arms;
FIGURES 9B and 9C are sectional end views
respectively along lines 9B-9B and 9C-9C of Figure 9A
showing the relationship of the abutment members and
the engaging fingers of each of the two picker
mechanisms;
FIGURE lOA is a front view of the robotic arms
shown in an aligned disc transfer position;
FIGURE lOB is a sectional end view along line
lOB-lOB of Figure lOA showing the relationship of the
abutment members and the engaging fingers of both
picker mechanisms when in their position at Figure
lOA;
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FIGURES llA, 12A, 13A and 14A are front views
of the picker mechanisms showing their sequence of
operation in transferring a disc from one picker
mechanism to the other;
FIGURES llB, 12B, 13B and 14B are sectional end
views respectively along lines llB-llB to 14B-14B of
Figures llA to 14A showing the relationship of the
abutment members and the engaging fingers of both
picker mechanisms;
FIGURE 15A is a front view showing the robotic
arms back to their horizontal positions after the disc
has been transferred from one picker mechanism to the
other; and
FIGURES 15B and 15C are sectional end views
respectively along lines 15B-15B and 15C-15C of Figure
15A showing the relationship of the abutment members
and engaging fingers of both picker mechanisms of
Figure 1 5A .
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawings, and more
particularly to Figure 1, there is shown generally at
10 the automatic disc handling system of the present
invention for retrieving and positioning information
carrying discs, such as video discs 11 and 11' shown
in Figure 3, between storage positions 12 positioned
to each side of a plurality of bays of playback units
13. In the particular instance the discs have a
diameter of about 12 inches. The bay containing the
playback units 13 is herein considered as the position
of use whereas the bays 12 contain a plurality of
storage positions. The storage positions are defined
by a plurality of vertical storage frames 14, each
containing a plurality of horizontally superposed
sliding trays 15, the details of which will be
described later. AS can be seen, the storage bays 12
and the bay containing the playback units 13 are
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disposed on an arc of a circle. On the center axis 16
of this arc is disposed a pivoting robot 17. This
robot acts as a server to manipulate the discs at and
from their storage position in the storage bays to
S their position of use in the playback units 13.
Referring now to Figure 2, there is shown a
simplified block diagram of the automatic disc
handling system of the present invention. The robot
17 is controlled by a robot controller 16 connected to
a programmed computer 18 which is provided with a
memory 19 to retain various information therein, such
as the location address of each disc stored in the
sliding drawers 15 or positioned in the playback units
13, or held by one or both of the picker mechanisms of
lS the robotic arms 21, as illustrated in Figure 3.
The computer controller 18 is controlled by at
least one personal computer unit 22 which is located
remotely from the robot area, such as in an adjacent
room, and which is operated by a user person. A
console 23 or viewing screen is associated with the PC
unit so that the user has access to the audio and
video information on the disc. The console could be a
speaker system if the discs being handled were audio
discs. In the particular instance, the disc handled
2s by the system contain video and audio digitized
information signals which are scanned by a laser
scanner (not shown) provided in the playback unit to
provide the user person both audio and video signals
of the information accessed by the user person and
stored on both sides of the disc. The playback units
13 are interfaced with the computer 18 via an
interface circuit 24 which performs switching and
control of a selected playback unit 13. As herein
shown, the user person could also be located at a
remote station, such as at 25, far away from the area
where the discs are stored, and these discs can be
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accessed through a modem 26 connected to the computer
18 through telephone lines.
Referring now to Figure 5A, there is shown the
construction of the vertical storage frame and as
S herein shown the storage frame consists of a pair of
vertically oriented side walls 27 held by end walls
and each having a plurality of elongated parallel
slots 28 formed in an inner side face 29 thereof. The
slots 28 of each side wall 27 are in horizontal
alignment with one another to receive a plurality of
the sliding trays 15 in closely spaced parallel
relationship. The trays 15 are elongated rectangular
trays which may contain one or more discs 11 in disc
retaining cavities 30' formed in the top surface
thereof and separated by spacers 31. The cavities
have a circular contour shape. The trays 15 are also
provided with opposed guide flanges 33 elevated from
the tray bottom wall 30 by suspension walls 33' and
engaged by the slots 28 to position the trays in very
close horizontally stacked relationship, as shown in
Figure 5B, with the distance between trays having a
very small clearance. However, to overcome the
retrieval problems of having closely spaced trays,
each of the trays are provided with an engageable
aperture 34 which is constructed so as to make it easy
to grasp the tray to retrieve a disc.
Referring now additionally to Figures 6A and
6B, it can be seen that an engageable aperture 34 is
formed in the front edge 35 of the trays 15, and is
provided with an undercut groove 36 to one side
thereof to define an engageable lip 37 on the right or
the left side of the aperture 34. The trays are then
stacked with their lips 37 of adjacent trays in an
alternating sequence, as can be seen in Figure 5A.
Accordingly, the lips of adjacent trays are spaced a
distance of two trays and will not interfere with one
another when being engaged.
209:~ 6~3
As shown in Figure 3, the head 38 of the robot
is provided with a tray engaging finger element 39
which is a T-shape finger element having opposed
engaging arms 40. A tray is retracted from the
storage frame 14 by the robot which places its finger
element 39 with its T-shape fingers 40 directly within
the aperture 34 and centrally thereof, as shown in
Figure 6A. An optical sensor 41, herein the end of a
fiber optic cable, is located centrally of the end of
the finger element between the arms 40 to check the
alignment of the engaging arms 40 with the front edge
35 of the tray to be retracted. The finger engaging
element is then moved to one side of the aperture 34
where the lip 37 is located, as shown in Figure 6B,
and then retracted, as shown in Figure 6C, so that one
of the engaging arms 40 engages the lip and retracts
the drawer, as therein shown. This movement of the
finger element 39 is effectuated by command signals
from the robot controller 16.
The robot controller 16 has in a memory 20 the
precise position of a selected tray to be retracted,
as well as the position of the lip on that tray. The
tray engaging finger is therefore automatically guided
precisely to that position as stored in the memory 20
of the robot controller 16. The tray is then pulled
to a loading and unloading position, as shown at 42 in
Figure 6C, where the disc 11 is then ready to be
unloaded. As shown in Figure 6C, the tray 15 is a
rectangular tray carrying, in the particular instance,
a single disc 11. The tray 15' positioned thereunder
is also illustrated with its lip 37' positioned on the
opposite side as the lip 37 of the uppermost tray 15.
The selected disc 11 is thus in a position to be
removed from its storage sliding tray 15. As can be
seen in Figure 5A, should the other disc 11" on a
given tray be selected, the robot controller 16 also
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has in its memory the precise location of this other
disc 11", and therefore pulls the tray accordingly.
Referring to Figure 5B, there is shown an
alternative construction of the engageable means for
S displacing the trays 15. The trays are formed with
flat horizontal tabs 9 having an engageable aperture
or hole 34' formed therein. The tab 9 of adjacent
trays 15 in the storage frames 14 is disposed at
different locations along the front edge 35' of the
trays so as to permit for a larger clearance between
vertically aligned tabs for ease of passage of the
tray engaging element 39'. As shown in Figure 5B, the
tabs 9 are disposed at four distinct locations in the
front edge 35' of the trays 15, thereby providing a
clearance of three suspended trays between vertically
aligned tabs.
The tray engagement element 39' is an L-shaped
element herein constituted by a straight rod having a
right angled engaging end 40' which is positionable
into an aperture 34' of a selected tab 9 to engage and
displace the tray 15 as above described.
As shown in Figure 3, a pair robotic arms 21
are pivoted at pivot connections 43 to braces 44 of
the head 38. A displaceable mechanism 69 causes the
arms to simultaneously move along individual arcs
about their pivot connections, as will be described
later. The displacement of the arms 21 is commanded
by the robot controller 16. As also shown in Figure
1, the head 38 is secured to an articulation 46 at the
end of a boom' 47 which is also articulated to a
robotic frame 48 where by the picker mechanisms 20 at
the end of the arms 21 can be displaced to any angle
in horizontal and vertical planes. The mechanism 69
consists in a pair of blocks 76 and 76' on which are
respectively mounted pulleys 45 and 45' on which
elongated metal spring bands 79 and 79' are wound.
Such spring bands are provided to retain robotic arms
-
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in position in case of cylinder air supply failure.
Connecting rods 84 and 84' secured to respective
blocks 76 and 76' are pivotally connected to robotic
arm 21 by pivots 85 and 85'. A bridge member 80
connects the blocks 76 and 76' and is secured to a
piston rod 81 having a plunger 82 displaceable within
an air-operated bi-directional cylinder 83.
Referring again to Figure 3, it can be seen
that the picker mechanism 20 is provided with three
vertically disposed parallel abutment posts 49
equidistantly spaced from one another along a
circumferential axis 50 of a circle, as shown in
Figure 9B. Disposed on an inner circle arc of the
abutment member are three articulated disc aperture
engaging fingers 51 which are displaceable from a
retracted position, as shown at 52 in Figure 9A, to a
disc engaging expanded position, as shown at 53 also
in Figure 9A. These fingers are secured on pivot
connections 54 to an axially displaceable support air-
actuating mechanism 55. Although there are three discabutment posts 49 being shown and three aperture
engaging fingers 51, it is conceivable that the picker
mechanism could operate with only two of each of
these, if they are properly shaped to carry on
centering of a picked disc. It is also conceivable
that the picker mechanism could be comprised solely by
air-operated suction cups or a single cup attached to
the free end of the robotic arms 21, and having
sensors provided in close relationship thereof to
locate the suction cups at desired locations on the
disc. Various other sensors, such as sensor 68, as
shown in Figure 3, are located at different strategic
positions with respect to the displaceable mechanisms,
such as the air-actuating mechanism 55, for precise
alignment and displacement, or for locating reference
marks to provide precise operation of the robot in a
manner well known in the robotic design art. More
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specifically, sensor 68 is provided to check over one
of the tray apertures 61, if a selected disc is
effectively in the position as stored in the computer
memory 19. As also shown in Figure 9A, the axial
displacement actuating mechanism 55 is secured to a
piston rod 57 having a plunger 58 displaceable within
an air-operated cylinder 59.
As shown in Figure 9A, the disc engaging
fingers 51 at their retracted position 52 are closely
spaced in alignment with one another. The fingers are
also provided with a hook end 51 ' for engaging the
disc 11, in a manner as will now be described.
AS shown in Figure 7, after the sliding tray 15
has been retracted to a disc loading and unloading
lS position 42, the head 38 of the robot is then
articulated to a disc engaging position so that one of
the arms 21 has its picker mechanism 20 aligned
directly above the disc engaging aperture 60 ( see
Figure 6C) provided at the center of the disc 11. As
also shown in Figure 6C, the support wall 30 of the
tray is provided with a plurality of apertures 61 to
reduce the weight of the tray and for ventilation.
With the robotic arms 21 in their position, as
shown in Figure 7, the picker mechanism is then
actuated to perform a disc engaging function, as
illustrated by Figures 8A to 8D. AS shown in Figure
8A, the picker mechanism has been moved laterally in
the direction of arrow 62 to position itself directly
centered with the disc engaging aperture 60. The
picker mechanism is then lowered to an engaging
position by the displaceable mechanism 69 so that the
aperture engaging fingers 51 move downwardly in the
direction of arrow 63 to position itself within the
aperture 60 with the hook ends 51 ' extending above the
back side 64 of the disc 11.
AS shown in Figure 6C, the tray support wall 30
is provided with a large central aperture 65 to
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provide a clearance about the disc engaging aperture
60 to permit engagement of these hook ends 51 with the
back side 64 of the disc about the aperture 60. Once
in this position the engaging fingers are pivoted by
the actuating mechanism 55 to move to a disc engaging
position with the hook ends 51' moving outwardly in
the direction of arrows 66. After the fingers and the
hook ends are in an engageable position, as shown in
Figure 8C, the piston rod 57 is then retracted within
its air-operated cylinder 59 to retract the disc and
urge it in clamping position between the hook ends 51'
and the cushion bumpers 67 secured at the free ends of
the abutment posts 49, as shown in Figure 8D.
With the disc thus engaged, the head of the
robot then realigns itself with the tray having been
pulled to its loading and unloading position 42, as
shown in Figure 7, and the tray engaging finger
element 39 relocates itself within the engaging
aperture 34, and pushes the tray back to its storage
position, as shown by tray 15" in Figure 5A. The
articulated arm 46 of the robot then swings the head
38 to locate it adjacent a selected one of the
plurality of playback units 13. Each of the playback
units 13 is associated with a specific one of a
plurality of PC units 22 located in a viewing room or
a remote unit 25 located at a far end. The computer
18 now gives a command signal to the selected playback
unit 13 to automatically place its drawer or disc
receiving platform (not shown) to a disc loading or
unloading position, as is obvious to a person skilled
in the art and as provided with many of these units
currently on the marketplace. The computer 18
contains in its memory various information about the
selected playback unit. If there is an optical disc
in that unit, the free robotic arm 21 of the robotic
head will first pick up the disc in that playback unit
by its picker mechanism, as previously described with
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209~6~3
reference to Figures 8A to 8D. The head will then
articulate again to position the disc removed from the
storage tray to a position above the loading platform
of the playback unit and deposit the disc thereon at a
precise location by retracting its aperture engaging
fingers 51 to position them to their retracted
position, as shown in Figure 9A.
Because the optical discs 15 as herein utilized
contain digitized recorded information on opposed
sides thereof, it may become necessary to invert the
disc after one side of the disc has been scanned and
transmitted to the user console 23. The computer
controller has the information in memory that such a
disc reversal is necessary at a specific time, and
lS this will be effectuated automatically by the robotic
arms, in a fashion as illustrated in Figures 9A to
15C. As shown in Figure 9A, a robotic arm 21' has a
disc 11 retained by its picker mechanism 20', and it
is now necessary to transfer that disc to the picker
mechanism 21 so that the back side 64 will now face
upwardly when the disc is retained by the picker
mechanism 20 of the robotic arm 21. As shown in
Figures 9B and 9C, the aperture engaging fingers 51 of
the picker mechanism 20' are in an engaged position
with the disc 11 retained captive between their hook
ends 51' and the abutment post 49 while the aperture
engaging fingers 51 of the other picker mechanism 20
are in a retracted position, as shown at 52 in Figure
9A.
As shown in Figures lOA and lOB, the robotic
arms 21' and 21 are then caused to articulate in a
downwardly arcuate direction, as shown by arrows 70,
so that the engaging fingers 51 of the pair of robotic
arms 21 and 21' are aligned about a common axis 71
extending through the center of the disc aperture 60.
The abutment posts 49 of opposed picker mechanisms 20
and 20' are also aligned on opposed sides of the disc
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11. Figure lOB illustrates the position of the
aperture engaging fingers with respect to one another,
with one set of fingers being at their retracted
position 52 and the other set at their disc engaging
position 53 and offset from one another.
The next step in this transfer sequence is
illustrated in Figures llA and llB. As shown by arrow
71, the piston cylinder 59 of the picker mechanism 20
is actuated to move the aperture engaging fingers 51
thereof through the aperture 60 and the disc 11 and
between the aperture engaging fingers 51 of the picker
mechanism 20' which are in their engaging position.
The relationship of the aperture engaging fingers 51
is illustrated in Figure llB.
The next step in the operation, as illustrated
in Figure 12A, consists in actuating the aperture
engaging fingers 51 of the picker mechanism 20 to
place them in a disc engaging position, and
accordingly these fingers will move outwardly in the
direction of arrows 72. The relationship of the
aperture engaging fingers 51 of both picker mechanisms
is illustrated in Figure 12B.
As shown in Figure 13A, the aperture engaging
fingers 51 of the picker mechanism 20' then retract to
their retracted position in the direction of arrows
75, and the relationship of these aperture engaging
fingers is illustrated in Figure 13B. The cylinder 59
of the picker mechanism 20 is again operated in the
direction of arrow 76 to withdraw the hook ends 51' of
the fingers against the top face 73 of the disc 11,
while the rear face 64 faces the picker mechanism 20.
The relationship of the aperture engaging fingers 51
is again illustrated in Figure 14B. The cylinder 83
is again operated, and articulated robotic arms 21 are
then retracted to their original position, as shown by
arrows 74 in Figure 15A, and the disc has been
transferred to the picker mechanism 20 with the
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original back side 64 now facing upwardly. The disc
can then be placed back on the support surface or
table of the playback unit, or else positioned in a
sliding tray 15 when the robot is given instructions
to retrieve another disc.
It is pointed out that while the robot is at
its position of use in front of the playback units 13,
and has retracted a disc from one of these units, it
does not immediately return the disc to the storage
trays. This is only effectuated once the robot is
given instructions to retract another disc. When
another disc is retracted, the disc held by one of the
robotic arms will be placed back in the same disc
retaining cavity of the same tray where a disc has
- lS just been withdrawn, and the computer controller will
maintain the new location of this stored disc in
memory for future retrieval.
It is also pointed out that the robot can also
interchange discs between storage sliding trays. The
computer can also maintain the time the PC unit was
occupied, and can transmit this information as well as
other information to another computer for purposes of
processing order or invoicing, etc. Accordingly, with
the system as above described, there can be provided a
fully automated system having a multitude of
capabilities. Also the storage bays and construction
of the storage frames and sliding trays provide for
expandable storage space and a means for storing a
great number of discs in dense compact space with ease
of retrieval of the discs.
It is within the ambit of the present invention
to cover any obvious modifications of the preferred
embodiment described herein, provided such
modifications fall within the scope of the appended
claims.
