U.S. patent application number 10/185722 was filed with the patent office on 2003-01-23 for automatic printing plate feeding system.
Invention is credited to Korolik, Pavel, Solomon, Yehuda Barnes.
Application Number | 20030017035 10/185722 |
Document ID | / |
Family ID | 24283223 |
Filed Date | 2003-01-23 |
United States Patent
Application |
20030017035 |
Kind Code |
A1 |
Solomon, Yehuda Barnes ; et
al. |
January 23, 2003 |
Automatic printing plate feeding system
Abstract
An automatic plate feeding system for loading plates of various
sizes into a printing plate imaging device, which includes a
plurality of trays staggered one on top of the other is provided.
At least two of the trays contain plates of different sizes stacked
with their sensitive side downward. Separation papers are
interposed between the plates. The automatic plate feeding system
includes suction cups, which touch the non-sensitive surface of the
plate, and a loading mechanism for loading plates from the trays
and feeding the loaded plates to the imaging device.
Inventors: |
Solomon, Yehuda Barnes;
(Rishon Lezion, IL) ; Korolik, Pavel;
(Petah-Tiqwa, IL) |
Correspondence
Address: |
Eitan, Pearl, Latzer & Cohen-Zedek
10 Rockfeller Plaza
Suite 1001
New York
NY
10020
US
|
Family ID: |
24283223 |
Appl. No.: |
10/185722 |
Filed: |
July 1, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10185722 |
Jul 1, 2002 |
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09571325 |
May 15, 2000 |
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6422801 |
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Current U.S.
Class: |
414/416.07 |
Current CPC
Class: |
B65H 3/0816 20130101;
B65H 3/44 20130101; B65H 3/0833 20130101; B65H 2701/1928 20130101;
B65H 2405/332 20130101 |
Class at
Publication: |
414/416.07 |
International
Class: |
B65H 003/44 |
Claims
What is claimed is:
1. Automatic plate feeding system comprising: a plurality of trays
staggered one on top of the other; and a loading unit to load
plates from said plurality of trays and to feed said plates to an
imaging device, said loading unit comprising at least one sensor
capable of distinguishing between said plates and separation papers
interposed there between.
2. The system of claim 1, wherein said loading unit comprises: a
horizontal bar rotatable around its longitudinal axis and having
one or more suction cups attached thereto to pick up said
plates.
3. The system of claim 2, wherein said horizontal bar further
comprises grippers to grip said separation papers.
4. The system of claim 2, wherein said loading unit further
comprises: two vertical rails to carry said horizontal bar, said
vertical rails movable in a horizontal direction perpendicular to
said longitudinal axis.
5. The system of claim 2, wherein said horizontal bar is movable in
a vertical direction.
6. The system of claim 2, wherein said loading unit further
comprises: two vertical rails to carry said horizontal bar, said
vertical rails rotatable about an axis parallel to and below said
longitudinal axis.
7. The system of claim 1, wherein a control unit coupled to said
imaging device activates said loading unit.
8. The system of claim 1, further comprising: a paper bin having
dimensions exceeding the dimensions of the largest of said
plates.
9. The system of claim 8, wherein said paper bin is positioned
below the lowest of said trays.
10. The system of 1 further comprising: one or more rails
positioned below the lowest of said trays to carry a shipping
container filled with imaging plates, wherein a top surface of said
container is removed.
11. The system of 1 further comprising: two or more paper bins; and
one or more rails positioned below the lowest of said trays to
carry said paper bins.
12. A method comprising: positioning a loading unit having one or
more suction cups and one or more grippers attached thereto in
proximity to one of a plurality of staggered trays each having
plates with separation papers interposed therebetween; activating a
sensor to determine if a surface directly below said suction cups
is a surface of one of said plates; and if so lifting said one of
said plates with said suction cups.
13. The method of claim 12, further comprising: arranging said
plates within said trays such that a non-sensitive surface of each
of said plates is facing upward.
14. The method of claim 13, further comprising: positioning said
suction cups onto a non-sensitive surface of said one of said
plates.
15. The method of claim 12 further comprising: when said sensor
determined that said surface directly below said suction cups is a
surface of one of said separation papers, gripping said one of said
papers; and disposing said one of said separation papers into a
disposal bin.
16. The method of claim 15, wherein disposing said paper comprises
spreading said paper in said bin.
17. The method of claim 15, further comprising: when said disposal
bin is filled with said papers, automatically moving said disposal
bin to advance an additional disposal bin to a predefined
position.
18. The method of claim 12, further comprising: positioning in a
staggered manner below the lowest of said trays said plates a
shipping container filled with additional plates such that a
non-sensitive surface of each of said additional plates is facing
upward; and removing the top surface of said packaging container.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation in part of U.S.
patent application Ser. No. 09/571,325, filed May 15, 2000.
FIELD OF THE INVENTION
[0002] The present invention generally relates to a system for
loading a printing plate into a plate imaging device and
specifically to a system for automatic loading of plates of various
sizes into a plate setter or a printing plate imaging device.
BACKGROUND OF THE INVENTION
[0003] A variety of systems and applications use stacks of sheets
or plates, which may be made of metal, paper, plastic and the like.
Printing plates (hereinafter singly or collectively referred to as
"plates") are typically stacked in a tray or similar container,
which houses the plates and facilitates their protection,
transportation and handling.
[0004] A specific system using plates generally uses trays having
specific dimensions. Trays can usually be set to contain plates of
various sizes, but all plates in the same tray are of one size.
Usually the plates are manually removed from the cassette or the
shipping container and inserted into the trays for use by the
system, for example, a plate imaging system.
[0005] Plates are usually packed in the cassette with intermediate
paper sheets, hereinafter referred to as `separation paper`. The
separation papers are disposed during loading into the imaging
device by a mechanism such as described in U.S. Pat. No. 6,164,637
assigned to the common assignee of the present invention.
[0006] A typical conventional plate feeding system from a tray is
shown schematically in FIG. 1. Plates 12 are supplied, within a
tray 14, stacked one on top of the other with separation papers 16
between the plates.
[0007] Various mechanisms have been developed for removing a single
plate 12 from the tray 14 and loading it using loading arm 18 to
the loading plane 23 of the imaging system 20. Usually the feeding
system includes a mechanism for disposing of the separation paper
16 into a paper bin 22 illustrated, for example.
[0008] One such system is described in U.S. Pat. No. 5,785,309
assigned to the common assignee of the present invention. The
loading method described has the disadvantage in that, if a
different plate size needs to be loaded for a subsequent operation,
then the tray in use needs to be replaced by a tray containing the
required plate size, or the tray itself needs to be replenished
with plates of the required size. Replacing trays is a costly
procedure and time consuming operation.
[0009] U.S. Pat. No. 5,367,360 to Mcllwraith et al. describes a
method for loading plates from a single tray. In this case, the
cardboard shipping container is used as a tray and the plates are
lifted and loaded vertically by a vacuum system.
[0010] The use of several trays with the same system is known in
the art of copiers, for example, where paper is loaded selectively
from different trays. The trays are stacked one on top of the
other, each having a separate loading mechanism.
[0011] U.S. Pat. Nos. 5,655,452, 5,738,014, 5,791,250, 5,788,455
describe an apparatus and method of loading plates from a plurality
of trays into an imaging device. The trays are stacked one on top
of the other and moved by an elevator mechanism to allow a loading
arm to enter between the trays and pick-up a specific plate.
[0012] U.S. Pat. No. 4,984,260 to Koyama describes an automatic
loader for films used in radiation diagnostics. This loader employs
static staggered cassettes, a belt-type picking mechanism, which
moves the films to an irradiation station, which is placed on top
of the cassettes.
[0013] Trays containing printing plates are heavy and bulky, and
moving such tray up and down requires complicated and expensive
mechanism and is time consuming. There is, thus a widely recognized
need for an automatic and efficient handling system of loading
plates of various sizes to a plate imaging system, without the need
to move trays.
[0014] Furthermore, the loading device may contain a large space
for disposing the separation papers, a flat table for pre-exposure
operations, such as punching registration holes in the plates, and
a picking arm. It is desired that those units be packed into
minimum floor space.
SUMMARY OF THE INVENTION
[0015] The present invention discloses a compact system for
automatically feeding plates of various sizes from a group of
staggered trays.
[0016] The present invention provides an automatic plate feeding
system, which can be used to automatically feed plates of various
sizes into a printing plate imaging device.
[0017] According to the present invention, there is provided a
plate feeding system for grasping and moving a plate from a stack
of plates housed in a plurality of trays. The stack of trays is
static and staggered.
[0018] The system includes a plurality of trays staggered one on
top of the other, wherein at least two of the plurality of trays
contain plates of different sizes, the plates usually have
separation papers interposed there between; and loading unit for
loading plates from the trays and feeding them to an imaging
device.
[0019] The loading unit may be an arm mechanism, which includes a
plate grasping member for grasping the plate, sensors for
distinguishing between plate and separation paper, and a separation
paper disposing system. The grasping mechanism is movable
perpendicularly to the arm by a vertical rod, which is movable by
the carriage. The carriage is movable along the X-arm, which is
typically parallel to the plates.
[0020] The trays are staggered in a way so that the grasping
mechanism can be brought to each of the trays' openings, grasp a
plate and feed it to the imagesetter, or grasp a separation sheet
and dispose it into the paper bin.
[0021] According to some embodiments of the invention described
below, the plate grasping member is an array of suction cups, and
the feeding into the imagesetter is done in a general X direction
to the right of the stack of trays.
[0022] In another configuration the X-Y arm mechanism is of the
gantry type and includes a plate grasping member for grasping the
plate, sensors and a separation paper disposing system. The
grasping mechanism is movable in the orthogonal X-Y directions and
rotatable. The X rail of the gantry type arm mechanism is typically
parallel to the plates.
[0023] The trays are staggered in a way that the grasping mechanism
can be brought to each of the tray's openings, grasp a plate and
feed it to the imagesetter, or to grasp a separation sheet and to
dispose it into the paper bin.
[0024] According to some embodiments of the present invention, the
plate grasping member is an array of suction cups, which grasp the
plate at its non-sensitive side, and the feeding into the
imagesetter is done in a general X direction to the left of the
stack of trays. A large paper disposal bin is available beneath the
stack of trays.
[0025] In another embodiment the gantry structure is operated as an
R-.THETA. arm, instead of the X-Y arm, described in the second
embodiment.
[0026] Where the transfer of plates from the shipping container to
the trays should be avoided, an open top shipping container can
replace the lowest tray in the staggered structure. For unattended
operations, which require a disposal of a large quantity of
separation papers, an automatic replacement method of disposal bins
is proposed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The present invention will be understood and appreciated
more fully from the following detailed description taken in
conjunction with the drawings in which:
[0028] FIG. 1 schematically describes a prior art plate loading
system from a single tray;
[0029] FIGS. 2A, 2B, 2C and 2D schematically illustrate a
multi-tray plate feeding system according to some embodiments of
the present invention;
[0030] FIG. 3 schematically illustrates a tray for use with the
staggered multi-tray plate loading system according to some
embodiments of the present invention;
[0031] FIG. 4 is a flow chart illustration of a typical operation
cycle of loading a plate to an imaging device out of a tray
according to some embodiments of the present invention; and
[0032] FIGS. 5, 6, and 7 schematically illustrate a multi-tray
plate feeding system according to some embodiments of the present
invention.
[0033] FIG. 8 schematically illustrates another configuration of a
multi-tray R-E plate feeding system, constructed and operative in
accordance with some embodiments of the present invention;
[0034] FIG. 9 schematically illustrates the option of using the
plates shipping container instead of the lowest tray in the
staggered multi-tray system according to some embodiments of the
present invention; and
[0035] FIG. 10 schematically illustrates the option of using one or
more paper disposal bins according to some embodiments of the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0036] Reference is now made to FIGS. 2A-2D and 3. FIGS. 2A-2D
illustrate the multi-tray plate loading system, generally
designated 30, constructed and operative in accordance with an
embodiment of the present invention. FIG. 3 schematically
illustrates a typical tray 32, for use with the multi-tray plate
loading system of FIG. 2. Each tray 32 is shown containing a
plurality of plates 34, placed in the tray with their non-sensitive
(no-emulsion) side up.
[0037] The multi-tray plate loading system 30 is especially
suitable for the automatic loading of plates of various sizes into
a plate setter or a printing plate imaging device, schematically
illustrated, referenced 25.
[0038] The multi-tray plate loading system 30 includes a loading
unit, which is a motorized arm mechanism, generally designated 36,
pivotally connected to imaging device 25, for loading plates 34
from the trays 32 and feeding them to imaging device 25.
[0039] Referring now particularly to FIG. 2A, the multi-tray plate
loading system 30 comprises a plurality of trays, referenced 32A,
32B and 32C holding stacks of plates referenced 34A, 34B and 34C
respectively, of different sizes. Separation papers 38 are inserted
to keep the plates apart from each other. The trays 32 are
staggered one on top of the other. The offset distance between the
trays is referenced W (FIG. 2A). In a typical application, W=70
mm.
[0040] Three trays are shown as an example only, but as will be
appreciated, any number of trays can be mounted one on top of the
other in a staggered manner.
[0041] Arm mechanism 36 is pivotal about a pivot point 40. During
the plate feeding/loading operation, arm mechanism 36 is
substantially parallel to the stack of plates 34 in the trays 32.
The arm mechanism 36 is tiltable so as to allow access to the trays
32.
[0042] Arm mechanism 36 comprises an arm 42, a motorized carriage
44, which can be activated to move along the arm 42, and a vertical
rod 46 connected to motorized carriage 44.
[0043] The motorized carriage 44 can be stopped automatically at
any desired position along arm 42.
[0044] Vertical rod 46 is movable vertically (perpendicular to arm
42) through motorized carriage 44, and can be stopped automatically
at any desired position. Vertical rod 46 comprises a bar 48
suitably attached to rod 46 at its lower end, and an array of
suction cups 50 attached to bar 48.
[0045] The bar 48 also carries separation paper grippers (not
shown) and sensors generally designated 70, which enable
distinction between plate 34 and separation paper 38. The
separation paper grippers may be any suitable known in the art
devices, such as those described in U.S. Pat. No 6,164,637,
assigned to the common assignee of the present invention, described
hereinabove.
[0046] The sensors 70 may be any suitable known in the art devices
and will not be further described. The distinguishing sensors are
preferably of the electrical contact type, as known in the art.
[0047] Motorized carriage 44 is coupled to a control unit 52, which
is preferably coupled to the control unit of imaging device 25.
Motorized carriage 44 is any suitable device, such as the
commercially available model 2EC "Powerslide" of Thomson Ind.
Industries. of New York, USA.
[0048] Also illustrated is the loading plane 54 for receiving the
plates being fed to imaging device 25.
[0049] Reference is now also made to FIG. 3, which illustrates a
typical tray 32. The base of the tray 32 comprises three adjustable
pins 58, located in slots 56, the adjustment of which defines the
overall dimensions of the plate 34 being stored. Two pins are
located proximal to an open end, referenced 60, and one of the pins
is located approximately in the center and proximal to the other
end, referenced 62. The pins 58 are inserted in the required slot
56, prior to loading the tray 32 with plates 34. The tray 32 is
open at the top, thus allowing for easy loading of plates 34.
Usually the plates 34 are stacked with their imaging sensitive
layer facing downwards. At open end 60, two rows of rollers 64, for
guiding the plates 34 being fed, are suitably fitted.
[0050] The dimensions of the tray 32 are determined by the maximum
size of plates to be loaded and the maximum number of plates to be
stacked.
[0051] Reference is also made to FIG. 4, which is a flow chart
illustration of a typical operation cycle of feeding a plate 34 to
the imaging device 25.
[0052] As shown in the example of FIG. 2A, three trays 32 are
stacked one on top of the other, and offset a distance W, as
shown.
[0053] In the initial, non-activated mode, the motorized carriage
44 is located at its default position, that is at one end of arm
42, proximal to imaging device 25 (step 202). Vertical rod 46 is
shown positioned at its highest point.
[0054] Upon receiving a command from control unit 52 (FIG. 2B), to
load a plate of a specific size (step 204), the motorized carriage
44 is activated to move along the arm 42 towards the tray
containing the required plate (say plate 34B in tray 32B)--(step
206).
[0055] Upon reaching the designated feeding position, motorized
carriage 44 stops and vertical rod 46 descends until the suction
cups 50 (together with separation paper grippers and distinguishing
sensors 70), are in contact with the uppermost plate in the tray
(step 208). The following step is conditioned by the existence of
separation paper between the plates, which might not exist for
certain plates.
[0056] The distinguishing sensors 70 indicate to the computerized
control unit 52, whether the top layer is a separation paper 38 or
a plate 34 (query box 210). Accordingly, depending on the upper
layer, the computerized control unit 52 either activates the
suction cups 50 (step 212) or the separation paper grippers (step
214).
[0057] On sensing contact with a plate 34, arm 42 is tilted so that
the suction cups 50 are perpendicular to the plate 34. The suction
cups 50 are then operated to grasp the plate 34 (step 212).
[0058] On the other hand, if the distinguishing sensors sense
contact with separation paper 38 control unit 52 will activate the
separation paper grippers 70 (step 214) to grip the separation
paper 38 and then dispose of it into the paper bin 22 (step
218).
[0059] After disposing of the separation paper 38 (step 218), the
plate loading sequence commences. As shown in FIG. 2C, vertical rod
46 is activated to move upwards a pre-determined amount, thus
causing the suction cups 50 to lift the end of the plate 34 from
the tray 32 (step 216).
[0060] As shown in FIG. 2D, the motorized carriage 44 is then
activated to move (step 220) towards the loading plane 54 of the
imaging device 25, dragging the plate 34 out of tray 32. The
rollers 64 facilitate the smooth movement of the plates 34 over the
edge of the tray 32.
[0061] On reaching the loading plane 54, rod 46 moves downwards and
releases the plate 34 (step 222). The arm mechanism 36 is then
returned to its initial position (step 224). The plate 34 is then
fed into the imaging device 25 by methods known in the art, for
example, U.S. Pat. No. 5,488,906 assigned to the common assignee of
the present invention.
[0062] Another configuration of a staggered tray printing plate
loading system is shown in FIG. 5. The loading system of FIG. 5
occupies minimum floor space, compared to the loading system of
FIG. 2A. This configuration is particularly useful when floor space
is at premium, and handling of the plate at its non-sensitive side
is desirable.
[0063] Referring now particularly to FIG. 5, the multi-tray plate
loading system 30 comprises a plurality of trays, referenced 32A,
32B and 32C holding stacks of plates referenced 34A, 34B and 34C
respectively, of different sizes. Separation papers 38 are inserted
to keep the plates apart from each other. The trays 32 are
staggered one on top of the other. The offset distance between the
trays is referenced W. In a typical application, W=70 mm.
[0064] Three trays are shown as an example only, but as will be
appreciated, any number of trays can be mounted one on top of the
other in a staggered manner.
[0065] A loading table 95 is placed above the staggered trays 32,
and the imaging device 25 is generally placed at the rear of the
loading system 30.
[0066] Loading unit 80 is of a gantry type, including: two rails
82, substantially parallel to the stack of plates 34 in the trays
32, mounted at the two sides of the staggered trays, and a "bridge"
110 having two substantially vertical rails 106, on which a
motorized carriage 86 can move in the "Y" direction 92.
[0067] The motorized carriage 86 includes a horizontal bar (not
shown) supported between the two rails 106. The carriage 86 and
attached bar can be stopped automatically at any desired position
along rails 106. The horizontal bar carries an array of suction
cups 50, separation paper grippers (not shown) and sensors
generally designated 70, which enable distinction between plate 34
and separation paper 38. The separation paper grippers may be any
suitable known in the art, such as those described in U.S. Pat. No.
6,164,637, assigned to the common assignee of the present
invention, described hereinabove.
[0068] The sensors 70 may be any suitable known in the art devices
and will not be further described. The distinguishing sensors are
preferably of the electrical contact type, as known in the art.
[0069] Motorized carriage 86 can rotate to an angle 94, having a
rotation center 88 on rail 106.
[0070] Motorized carriage 86 is coupled to a computerized control
unit 52, which is preferably coupled to the control unit of imaging
device 25. Motorized carriage 86 is any suitable device known in
the art.
[0071] The gantry "bridge" structure 110 is coupled to rails 82 by
another motorized carriage 84, which enables the movement of gantry
"bridge" 110 in the "X" direction 90. The gantry "bridge" 110 can
be stopped automatically at any desired position along rails 82.
Motorized carriage 84 is any suitable device, such as the
commercially available model 2EC "Powerslide" of Thomson Ind.
Industries of New York, USA.
[0072] Loading table 95 is tiltable at angle 100 and can optionally
have a separate X-Y mechanism 98 for handling the plate on the
loading table during pre-exposure operations and subsequently
loading that plate to imaging device 25. Pre-exposure operations 96
can include, for example punching of the plate (not shown) for
registration purposes. Independent handling of the plate by
loadings table 95 means that the main loading mechanism 80 can be
more efficient in paper 38 disposable and plate 34 selection and
feeding functions, which translates finally to a higher plate per
hour capacity of the entire loading system 30.
[0073] The non-used space available under the stack of trays 32 is
used for a large paper disposal bin 102. The disposed papers 38 can
be spread in the bin 102 in an orderly way, which maximizes the
usage of the bin.
[0074] Reference is made again to FIG. 4, which is a flow chart
illustration of a typical operation cycle of feeding a plate 34 to
the imaging device 25.
[0075] As shown in the example of FIG. 5, three trays 32 are
stacked one on top of the other, and offset a distance W, as
shown.
[0076] In the initial, non-activated mode, the motorized carriage
86 is located at its default position, that is at the top of gantry
"bridge" 110, the "bridge" itself is at the right extreme of the
stack of static trays 32 (step 202).
[0077] Upon receiving a command from control unit 52 (FIG. 6), to
load a plate of a specific size (step 204), both motorized
carriages 86 and 84 are activated to move along rails 106 and 82
respectively, towards the tray containing the required plate, say
plate 34B in tray 32B--(step 206).
[0078] Upon reaching the designated feeding position, both
motorized carriages 86 and 84 stop and carriage 86 descends until
the suction cups 50 (together with separation paper grippers and
distinguishing sensors 70), are in contact with the non-sensitive
side of the uppermost plate in the tray (step 208). The method of
picking the plate 34 and moving it to the loading table 95 is done
on the non-sensitive (no emulsion) side of the plate, with the
result of minimizing risk of damage to the sensitive side of the
plate.
[0079] The following step is conditioned by the existence of
separation paper 38 between the plates, which might not exist for
certain plates.
[0080] The distinguishing sensors 70 indicate to the computerized
control unit 52, whether the top layer is a separation paper 38 or
a plate 34 (query box 210). Accordingly, depending on the upper
layer, the computerized control unit 52 either activates the
suction cups 50 (step 212) or the separation paper grippers (step
214).
[0081] On sensing contact with a plate 34, the suction cups 50 are
then operated to grasp the plate 34 at its non-sensitive side (step
212).
[0082] On the other hand, if the distinguishing sensors sense
contact with separation paper 38, control unit 52 will activate the
separation paper grippers (step 214) to grip the separation paper
38 and then dispose of it into either paper bin 22 or paper bin
102, whichever is installed in the specific system 30 (step 218).
Paper bin 102, installed in the empty space below the stack of
trays 32, has dimensions exceeding the largest plate useful in
system 30, permitting orderly disposal of separation paper sheets
38 one on top of the other. This method represents a highly
efficient way of paper disposal. Paper bin 22 can be of the type
described in U.S. Pat. No. 5,771,794 assigned to the common
assignee of this invention.
[0083] After disposing of the separation paper 38 (step 218), the
plate loading sequence commences. As shown in FIG. 7, motorized
carriage 86 is activated to move and rotate on axis 88, thus
causing the suction cups 50 to lift the end of the plate 34 from
the tray 32 and move the plate to position 34-M (step 216).
Motorized carriage 86 is programmed to move further and rotate to
position 104, dragging the plate up-side-down to position 34-N.
Further movement to the left in the X direction 90 disposes the
plate on the loading table 95 (step 220), whereas the non-sensitive
side of plate 34 is in contact with loading table 95. If the
loading table 95 is equipped with an independent handling mechanism
for the plate, the plate is released from suction cups 50 (step
222) and the motorized carriage 86 returns to its default position
as shown in FIG. 5 (step 224), or moved immediately to pick up a
new plate from a given tray 32 as shown, for example, in FIG. 6
(steps 204 and 206).
[0084] Another configuration of a staggered tray printing plate
loading system 30 is shown in FIG. 8. This configuration, has the
same advantages as the one shown in FIG. 5, and is particularly
useful when floor space is at premium, and handling of the plate at
its non-sensitive side is desirable.
[0085] Referring now particularly to FIG. 8, the multi-tray plate
loading system 30 comprises a plurality of trays, referenced 32A,
32B and 32C holding stacks of plates referenced 34A, 34B and 34C
respectively, of different sizes. Separation papers 38 are inserted
to keep the plates apart from each other. The trays 32 are
staggered one on top of the other. The offset distance between the
trays is referenced W. In a typical application, W=70 mm.
[0086] Three trays are shown as an example only, but as will be
appreciated, any number of trays can be mounted one on top of the
other in a staggered manner.
[0087] The loading table 95 is placed above the staggered trays 32,
and the imaging device 25 is generally placed at the rear of the
loading system 30.
[0088] Loading unit 124 is of a R-.THETA. gantry type, including:
two rails 114, which are part of a bridge structure (not shown),
pivoted at center 126 including a motorized unit 116, as known in
the art, which is designed to move loading unit 124 to an angle
.THETA. marked 128. The motorized unit 116 can be stopped
automatically at any desired angle within .THETA.. A motorized unit
118, as known in the art, can move along rails 114 in direction R
marked 120, with an attached bar 130, which is substantially
parallel to the stack of plates 34. The carriage 118 including the
attached bar can be stopped automatically at any desired position
along rails 114. The horizontal bar 130 carries an array of suction
cups 50, separation paper grippers (not shown) and sensors
generally designated 70, which enable distinction between plate 34
and separation paper 38. The separation paper grippers may be any
suitable known in the art, such as those described in U.S. Pat. No.
6,164,637, assigned to the common assignee of the present
invention, described hereinabove.
[0089] The sensors 70 may be any suitable known in the art devices
and will not be further described. The distinguishing sensors are
preferably of the electrical contact type, as known in the art.
[0090] Motorized carriage 118 can rotate to an angle 116, having a
rotation center 122 on rail 114.
[0091] The operation of arm mechanism 124 is essentially similar to
that of loading unit 80 as described in FIG. 5, 6, 7, with the
exception that R-.THETA. movements are replacing X-Y movements.
[0092] The sequence of operations described in FIG. 4 is relevant
also to the multi-tray plate loading system 30 having arm mechanism
124 as shown in FIG. 8, with the exception that R-.THETA. movements
are replacing X-Y movements.
[0093] In certain applications it is advisable to use the original
shipping container in the plate loading system 30, avoiding the
time consuming and delicate operation of transferring the plates
from the container into a tray 32. This application is shown in
FIG. 9, where the shipping container 150 includes plates 34-C and
separation papers 38. The container 150 has substantially the
dimensions of the stack of plates stored in it. In this application
container 150 replaces the lowest tray 32-C, and is inserted on
suitable rails 149 to permit the offset distance W between trays.
The operation of picking a plate from container 150 is identical to
the same operation out of a tray 32.
[0094] In certain unattended applications, a large quantity of
separation papers is removed, above and beyond the capacity of a
single paper bin 22 and even paper bin 102. For such applications,
it is advisable to use the solution described in FIG. 10.
[0095] In FIG. 10 a group of wheeled paper bins 22 is arranged on
rail 136, where the bins can be advanced automatically in direction
34, as known in the art, and stopped at a predetermined position.
Once bin 22A is full it is moved automatically forward in direction
134 and is replaced by paper bin 22B. A number of reserve bins, for
example, 22B, 22C, 22D can be prepared for automatic replacement.
Photoelectric signalization, as known in the art, can be used to
indicate the maximum paper capacity of each bin 22, and the
computerized control unit 52 can do the movement automation.
[0096] The operator of system 30 can periodically remove full bins
22 from rail 136 in direction 134, empty the bins and return the
empty bins to the waiting line in direction 132. This method of
operation is particularly useful for long-term automatic and
unattended operation of the entire imaging system, including the
imaging device 25 and plate loading system 30.
[0097] It will be appreciated by persons skilled in the art that
the present invention is not limited to what has been particularly
shown and described hereinabove. Rather the scope of the present
invention is defined only by the claims which follow:
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