Information
-
Patent Grant
-
6675712
-
Patent Number
6,675,712
-
Date Filed
Friday, April 5, 200222 years ago
-
Date Issued
Tuesday, January 13, 200421 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Mereki; John A.
- Sabourin; Robert A.
-
CPC
-
US Classifications
Field of Search
US
- 101 477
- 101 409
- 101 479
- 101 480
- 101 483
- 101 3891
- 271 106
-
International Classifications
-
Abstract
An apparatus and method for picking a single printing plate from a stack of printing plates. The apparatus includes a plurality of suction cups, a peeler, a drive system for displacing the suction cups and the peeler against the surface of the top printing plate on the stack, a vacuum source for supplying a vacuum to the suction cups to secure the suction cups against the surface of the top printing plate, and a system for rotatably displacing the suction cups relative to the peeler to peel a portion of the top printing plate off of the stack. The center line of rotation of the displacing system is located at a contact point between the peeler and the surface of the top printing plate. This prevents any relative motion of the top printing plate against the next, underlying printing plate on the stack during the peeling operation.
Description
FIELD OF THE INVENTION
The present invention is in the field of imaging systems. More particularly, the present invention provides an apparatus and method for picking a single printing plate from a stack of printing plates.
BACKGROUND OF THE INVENTION
In external drum imaging systems, a movable optical carriage is commonly used to displace an image recording source in a slow scan direction while a cylindrical drum, having recording media mounted on an external surface thereof, is rotated with respect to the image recording source. The drum rotation causes the recording media to advance past the image recording source along a fast scan direction that is substantially perpendicular to the slow scan direction.
The image recording source may include an optical system for generating one or more imaging beams that are scanned across the surface of the recording media. Each imaging beam may be separately modulated according to a digital information signal representing data corresponding to the image to be recorded.
The recording media to be imaged by an external drum imaging system is commonly supplied in discrete, flexible sheets, hereinafter collectively referred to as “printing plates.” Each printing plate may comprise one or more layers supported by a support substrate, which for many printing plates is a plano-graphic aluminum sheet. Other layers may include one or more image recording (i.e., “imageable”) layers such as a photosensitive, radiation sensitive, or thermally sensitive layer, or other chemically or physically alterable layers. Printing plates that are supported by a polyester support substrate are also known and can be used in the present invention. Printing plates are available in a wide variety of sizes, typically ranging, e.g., from 9″×12″, or smaller, to 58″×80″, or larger.
A cassette is often used to supply a plurality of unexposed printing plates to an external drum imaging system. The printing plates are normally supplied in stacks of ten to one hundred, depending upon plate thickness and other factors, and are stored in the cassette. Interleaf sheets, commonly referred to as “slip sheets,” may be positioned between the printing plates to protect the emulsion side of the printing plates from physical damage (e.g., scratches), which could render a printing plate unusable for subsequent printing. When Interleaf sheets are not used, great care must be taken to avoid emulsion damage as each printing plate is separated from the stack, fed from the cassette into the external drum imaging system, and mounted on the external drum. Unfortunately, preventing such damage as the printing plates are unloaded and fed from a cassette to an external drum has proven to be a very difficult and expensive task in currently available external drum imaging systems, especially when larger (e.g., 45″ wide) printing plates are used.
SUMMARY OF THE INVENTION
The present invention provides an apparatus and method for picking a single printing plate from a stack of printing plates in an imaging system.
Generally, the present invention provides an apparatus, comprising:
a plurality of suction cups, a peeler, and a system for rotatably displacing the suction cups relative to the peeler, wherein a center line of rotation of the displacing system is located on a surface of the peeler.
The present invention also provides an apparatus for picking a printing plate from a stack of printing plates, comprising:
a plurality of suction cups, a peeler, a drive system for displacing the suction cups and the peeler against a surface of a top printing plate on the stack, a vacuum source for supplying a vacuum to the suction cups to secure the suction cups against the surface of the top printing plate, and a system for rotatably displacing the suction cups relative to the peeler to peel a portion of the top printing plate off of the stack, wherein a center line of rotation of the displacing system is located at a contact point between the peeler and the surface of the top printing plate.
The present invention further provides a method for picking a printing plate from a stack of printing plates, comprising:
displacing a plurality of suction cups and a peeler against a surface of a top printing plate on the stack;
supplying a vacuum to the suction cups to secure the suction cups against the surface of the top printing plate; and
rotatably displacing the suction cups relative to the peeler to peel a portion of the top printing plate off of the stack, wherein a center line of rotation of the displacement is located at a contact point between the peeler and the surface of the top printing plate.
The present invention also provides a method for picking a printing plate from a stack of printing plates, comprising:
displacing a plurality of suction cups and a peeler against a surface of a top printing plate on the stack;
supplying a vacuum to the suction cups to secure the suction cups against the surface of the top printing plate; and
peeling a portion of the top printing plate off of the stack, and preventing relative motion of the top printing plate against an underlying printing plate on the stack, by rotatably displacing the suction cups relative to the peeler, wherein a center line of rotation of the displacement is located at a contact point between the peeler and the surface of the top printing plate.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention will best be understood from a detailed description of the invention and embodiments thereof selected for the purpose of illustration and shown in the accompanying drawings in which:
FIG. 1
illustrates an external drum imaging system for recording images onto a printing plate.
FIG. 2
illustrates an example of an imaging system including a movable optical carriage and scanning system, usable in the external drum imaging system of FIG.
1
.
FIG. 3
is an end view of an external drum platesetter including a cassette, a printing plate picking system in accordance with the present invention, and a printing plate supporting and feeding system.
FIGS. 4-8
illustrate the operation of the external drum platesetter of FIG.
3
.
FIG. 9
illustrates the printing plate supporting and A feeding system.
FIGS. 10-16
illustrate the structure and operation of the printing plate picking system of the present invention.
FIGS. 17-18
illustrate a lip segment of an exemplary plate rest.
DETAILED DESCRIPTION OF THE INVENTION
The features of the present invention are illustrated in detail in the accompanying drawings, wherein like reference numerals refer to like elements throughout the drawings. Although the drawings are intended to illustrate the present invention, the drawings are not necessarily drawn to scale.
An example of an external drum imaging system
10
is illustrated in FIG.
1
. In this example, the imaging system
10
comprises an external drum platesetter configured to record digital data onto a printing plate
18
. Although described below with regard to an external drum platesetter, the plate picking system of the present invention may be used in conjunction with a wide variety of other types of external drum, internal drum, or flatbed imaging systems, including imagesetters and the like, without departing from the intended scope of the present invention.
The imaging system
10
generally includes a front end computer or workstation
12
for the design, layout, editing, and/or processing of digital files representing pages to be printed, a raster image processor (RIP)
14
for processing the digital pages to provide rasterized page data (e.g., rasterized digital files) for driving an image recorder, and an image recorder or engine, such as an external drum platesetter
16
, for recording the rasterized digital files onto a printing plate
18
.
A stack
20
of printing plates
18
is commonly supplied in a cassette
22
. A printing plate
18
is picked off of the stack
20
and subsequently mounted on an external drum
24
of the external drum platesetter
16
by an autoloading system
26
. The printing plates
18
on the stack
20
are arranged one on top of the other without the use of protective slip sheets.
The external drum platesetter
16
includes an external drum
24
having a cylindrical media support surface
30
for supporting a printing plate
18
during imaging. The external drum platesetter
16
further includes a scanning system
32
, coupled to a movable carriage
34
, for recording digital data onto the imaging surface
36
of the printing plate
18
using a single or multiple imaging beams
38
. An example of a scanning system
32
is illustrated in FIG.
2
. In particular, the scanning system
32
is displaced by the movable carriage
34
in a slow scan axial direction (directional arrow A) along the length of the rotating external drum
24
to expose the printing plate
18
in a line-wise manner when a single beam is used or in a section-wise manner for multiple beams. Other types of imaging systems may also be used in the present invention.
The external drum
24
is rotated by a drive system
40
in a clockwise or counterclockwise direction as indicated by directional arrow B in FIG.
1
. Typically, the drive system
40
rotates the external drum
24
at a rate of about 100-1000 rpm. As further illustrated in
FIG. 2
, the scanning system
32
includes a system
42
for generating the imaging beam or beams
38
. The system
42
comprises a light or radiation source
44
for producing the imaging beam or beams
38
(illustrated for simplicity as a single beam), and an optical system
46
positioned between the radiation source
44
and the media support surface
30
for focusing the imaging beam or beams
38
onto the printing plate
18
. It should be noted, however, that the system
42
described above is only one of many possible different types of scanning systems that may be used to record image data on the printing plate
18
.
In the external drum imaging system
10
shown in
FIG. 1
, the leading edge
48
of the printing plate
18
is held in position against the media support surface
30
of the external drum
24
by a leading edge clamping mechanism
50
. Similarly, the trailing edge
52
of the printing plate
18
is held in position against the media support surface
30
of the external drum
24
by a trailing edge clamping mechanism
54
. The leading edge clamping mechanism
50
and the trailing edge clamping mechanism
54
both provide a tangential friction force between the printing plate
18
and the media support surface
30
of the external drum
24
that is sufficient to resist the tendency of the edges of the printing plate
18
to pull out of the clamping mechanisms
50
,
54
, at a high drum rotational speed. Other known systems for mounting the printing plate
18
onto the external drum
24
may also be used.
A vacuum source
56
may be used to draw a vacuum through an arrangement of ports and vacuum grooves
58
(
FIG. 2
) to hold the printing plate
18
against the media support surface
30
of the external drum
24
. The vacuum source
56
may also supply a vacuum to a plate picking system that is configured to remove or “pick” the top printing plate
18
from the stack
20
of printing plates. A registration system (not shown), comprising, for example, a set of registration pins on the external drum
24
, and a plate edge detection system (not shown), may be used to accurately and repeatably position and locate each printing plate
18
on the external drum
24
.
The basic structure of an external drum platesetter
16
, which includes a plate picking system
100
for picking a single printing plate
18
from a stack
20
of printing plates
18
in accordance with the present invention, is illustrated in FIG.
3
. In this example, the stack
20
of printing plates
18
are provided in a cassette
102
having a printing plate supporting and feeding system
104
. The external drum platesetter
16
includes an external drum
24
having a cylindrical media support surface
30
for supporting a printing plate
18
during imaging. The external drum
24
is supported by a frame
106
. A drive system
40
rotates the external drum
24
during imaging. A scanning system
32
, carried by a movable carriage
34
, travels axially along the rotating external drum
24
to record digital data onto the imaging surface of a printing plate mounted on the external drum
24
. The external drum
24
and scanning system
32
are positioned on a base
108
.
The cassette
102
contains a stack
20
of printing plates
18
(e.g., twenty-five printing plates). Only four printing plates
181
,
182
,
183
,
184
, are illustrated in
FIG. 3
for clarity. Protective slip sheets are not present between the individual printing plates
18
of the stack
20
. The printing plates
18
are manually loaded and stacked within the cassette
102
, which is intended to be reusable. Alternately, the printing plates
18
may be automatically loaded into the cassette
102
using any suitable loading mechanism. The printing plates
18
are stacked with their emulsion sides facing toward the plate picking system The printing plate supporting and feeding system
104
is located within the cassette
102
, and generally comprises a plurality of plate feed beams
110
that are attached to, and extend between, a pair of endless, rotatable timing belts
112
(only one is shown in FIG.
3
). The stack
20
of printing plates
18
is located between the pair of timing belts
112
. The plate feed beams
110
are configured to support large printing plates
18
without the need for a center support. The profile of each plate feed beam
110
is designed with a high stiffness to weight ratio such that, when supporting a printing plate
18
in the manner described below with regard to
FIGS. 6 and 7
, the plate feed beams
110
will not deflect and contact the underlying stack
20
of printing plates
18
. In an alternate embodiment of the present invention, the stack
20
of printing plates
18
, as well as the printing plate supporting and feeding system
104
, are not enclosed within a cassette.
The timing belts
112
transfer the rotary motion of a drive system
114
, such as an electric motor, to a linear motion of the plate feed beams
110
. A guide roller (not shown) is positioned at the opposing side of each timing belt
112
to allow rotation of the timing belt. A controller (not shown) is used to accurately control the drive system
114
and resultant displacement of the timing belts
112
and plate feed beams
110
in a manner known in the art. As presented in greater detail below, the linear motion of the plate feed beams
110
operates to peel the top printing plate
18
, off of the stack
20
of printing plates, allowing the top printing plate
18
, to be subsequently loaded and mounted onto the media support surface
30
of the external drum
24
.
The plate picker system
100
of the present invention is used to pick up a bottom edge of the top printing plate
18
1
from the stack
20
. The plate picker system
100
generally comprises a plurality of suction cups
116
(only one is shown) arranged parallel to the bottom edge of the printing plates
18
on the stack
20
, a system
118
for displacing the suction cups
116
relative to the top printing plate
18
1
, and a vacuum source
56
for supplying a vacuum to the suction cups
116
.
The general operation of the plate picking system
100
of the present invention, and the printing plate supporting and feeding system
104
, is illustrated in
FIGS. 4-8
. The plate picking system
100
will be described in greater detail below with reference to
FIGS. 10-16
.
In
FIG. 4
, with the plate feed beams
110
in a “home” position within the cassette
102
, the suction cups
116
of the plate picking system
100
are moved by the displacing system
118
into contact with a bottom edge of the top printing plate
18
1
on the stack
20
. The suction cups
116
are moved toward and against the bottom edge of the top printing plate
18
1
as indicated by directional arrow
120
. A vacuum is applied to the suction cups
116
by the vacuum source, thereby securely coupling the bottom edge of the top printing plate
18
1
to the displacing system
118
.
In
FIG. 5
, the bottom edge of the top printing plate
18
1
is peeled away from the stack
20
of printing plates as the displacing system
118
moves the suction cups
116
away from the stack
20
as indicated by directional arrow
122
. The top printing plate
18
1
is displaced in direction
122
until the bottom edge of the top printing plate
18
1
is positioned outside the periphery of the timing belts
112
. The bottom edge of the top printing plate
18
, is held in this position by the displacing system
118
.
At this point in the operation of the printing plate supporting and feeding system
104
, as illustrated in
FIG. 6
, the drive system
114
rotates the timing belts
112
in the direction indicated by directional arrow
124
. This results in a corresponding displacement of the attached plate feed beams
110
. As the leading plate feed beams
110
pass under the bottom edge of the top printing plate
18
1
that is coupled to, and held stationary by, the displacing system
118
, the plate feed beams
110
engage and slide against the underside of the top printing plate
181
, effectively peeling the top printing plate
18
1
away from, and partially off of, the next printing plate
182
on the stack
20
. As shown in
FIG. 7
, rotation of the timing belts
112
continues in direction
124
until the top printing plate
18
1
is fully peeled off of the stack
20
and is supported by the plate feed beams
110
. At this point, with the printing plate supporting and feeding system
104
in a “plate loaded” position within the cassette
102
, the top printing plate
18
1
no longer contacts the next printing plate
182
on the stack
20
. During the “peeling” operation, the plate feed beams
110
do not contact the top surface (i.e., the emulsion side) of the next printing plate
18
2
on the stack
20
; the plate feed beams
110
only contact and slide against the underside of the top printing plate
18
1
. This prevents the emulsion side of the next printing plate
18
2
from being damaged.
The displacing system
118
(and attached top printing plate
18
1
) is shifted downward as indicated by directional arrow
126
to position the bottom edge of the top printing plate
18
1
above the nip rollers
128
. The vacuum supplied by the vacuum source to the suction cups
116
is then released, and the suction cups
116
are displaced away from the top printing plate
18
1
as indicated by directional arrow
130
. Guide means may be provided within the cassette
102
to direct the bottom edge of the top printing plate
18
1
between the pair of nip rollers
128
.
The nip rollers
128
, which may be formed as part of the cassette
102
or other suitable portion of the external drum platesetter
16
, operate to direct the bottom (i.e., leading) edge of the top printing plate
18
1
to a plate mounting system (not shown) that is configured to mount the printing plate onto the external drum
24
of the external drum platesetter
16
for subsequent imaging. The top printing plate
18
1
is shown mounted to the external drum
24
in FIG.
8
. Such a mounting system is disclosed in detail, for example, in U.S. Pat. No. 6,295,929, entitled “External Drum Imaging System,” which is incorporated herein by reference.
As illustrated in
FIG. 8
, after the printing plate
18
1
exits the cassette
102
, the drive system
110
reverses the direction of rotation of the timing belts
112
, thereby rotating the timing belts
112
in the direction indicated by directional arrow
132
. The rotation of the timing belts
112
, and the corresponding displacement of the plate feed beams
110
, continues until the plate feed beams
110
are returned to their “home” position within the cassette
102
. The next printing plate
18
2
on the stack
20
, which now assumes the role of the “top” printing plate, can be fed from the cassette
102
to the external drum
24
by repeating the steps described above with regard to
FIGS. 3-8
.
The printing plate supporting and feeding system
104
of the present invention is illustrated in greater detail in FIG.
9
. As shown, the printing plate supporting and feeding system
104
comprises a pair of timing belts
112
and a plurality of plate feed beams
110
attached to, and extending between, the timing belts
112
. Each plate feed beam
110
includes a series of rotatable rollers
134
that allow a printing plate
18
and the plate feed beam
110
to slide across each other with minimal resistance.
The structure and operation of the plate picking system
100
of the present invention is illustrated in detail in
FIGS. 10-16
.
The plate picking system
100
of the present invention is illustrated in its home position adjacent the nip rollers
128
in FIG.
10
. The plate picking system
100
includes a plurality of vacuum cups
116
(only one is shown) that are coupled to a vacuum manifold
140
. A vacuum source
56
(
FIG. 1
) selectively supplies a vacuum to the plurality of suction cups
116
through the vacuum manifold
140
. The vacuum cups
116
extend across at least a portion of the width of the stack
20
of printing plates
18
stored in the cassette
22
. Only three printing plates
18
1
,
18
2
,
18
3
, are illustrated in
FIG. 10
for clarity The vacuum manifold is mounted to the end of a movable, angled bar
142
. The angled bar
142
is secured to a pin
144
that is rotatably coupled to a drive system. In this embodiment, the drive system comprises a pneumatic cylinder
150
, wherein the pin
144
is rotatably coupled to the end
146
of the piston
148
of the pneumatic cylinder
150
. The pneumatic cylinder
150
is rotatably coupled to a pin
152
that is secured to a movable platform
154
.
A curved slot
156
that comprises a segment of a circle is formed in the movable platform
154
. A pair of wheels
158
, which are attached to the underside of the angled bar
142
by axles
160
, are positioned within the curved slot
156
. The angled bar
142
is located above the movable platform
154
. The pair of wheels
158
extend below the angled bar
142
into the curved slot
156
.
An arc-shaped peeler
162
is positioned adjacent the vacuum cups
116
. The arc-shaped peeler
162
extends across at least a portion of the width of the stack
20
of printing plates
18
stored in the cassette
22
. A support
164
is mounted to each end of the arc-shaped peeler
162
. A first drive system
166
is provided for displacing the peeler
162
and the movable platform
154
in unison toward and away from the stack
20
as indicated by directional arrow
168
. The first drive system
166
may comprise any suitable type of linear drive system including a pneumatic cylinder, a motor driven belt/chain system, etc.
A second drive system
170
is provided for displacing the peeler
162
, the movable platform
154
, and the first drive system
166
in unison between the nip rollers
128
and the stack
20
of printing plates
18
in the cassette
22
as indicated by directional arrow
172
. The second drive system
170
may also comprise any suitable type of linear drive system including a pneumatic cylinder, a motor driven belt/chain system, etc.
As shown in
FIG. 11
, the peeler
162
, the movable platform
154
, and the first drive system
166
are displaced by the second drive system
170
as indicated by directional arrow
174
to position the peeler
162
and the vacuum cups
116
adjacent the bottom edge of the top printing plate
18
1
on the stack
20
. The piston
148
of the pneumatic cylinder
150
is extended during or after the displacement. This results in a displacement of the wheels
158
of the angled bar
142
within the curved slot
156
as indicated by directional arrow
176
. The curvature of the slot
156
causes the pin
144
and the angled bar
142
to rotate clockwise as indicated by directional arrow
178
, thereby positioning the vacuum cups
116
even with the peeler
162
and normal to the surface of the top printing plate
18
1
on the stack
20
. The centerline (CL) of rotation of the angled bar
142
within the curved slot
156
is located at the mid-point of the surface
180
of the peeler
162
. Thereafter, as illustrated in
FIG. 12
, the first drive system
166
displaces the peeler
162
and the suction cups
116
as indicated by directional arrow
180
to position the peeler
162
and the suction cups
116
against the bottom edge of the top printing plate
18
1
. A vacuum is subsequently supplied to the suction cups
116
through the vacuum manifold
140
to secure the suction cups
116
to the bottom edge of the top printing plate
18
1
.
Once the top printing plate
18
1
has been secured by the suction cups
116
, the piston
148
of the pneumatic cylinder
150
is retracted as illustrated in FIG.
13
. This results in a displacement of the wheels
158
of the angled bar
142
within the curved slot
156
as indicated by directional arrow
18
2
. The curvature of the slot
156
causes the pin
144
and the angled bar
142
to rotate counter-clockwise as indicated by directional arrow
184
, thereby peeling the bottom edge of the top printing plate
18
1
off of the stack
20
. The centerline (CL) of rotation of the angled bar
142
within the curved slot
156
is located on the surface of the top printing plate
18
1
at the mid-point (i.e., the contact point) of the surface
180
of the peeler
162
. This ensures that as the top printing plate
18
1
is peeled from the stack
20
, there is no relative motion (e.g., rubbing) of the top printing plate
18
1
against the next, underlying printing plate
18
2
on the stack
20
. The top printing plate
18
1
, therefore, does not rub or otherwise damage the delicate emulsion surface of the next printing plate
18
2
.
The cassette
22
includes a lip
186
that acts as a plate rest. The lip
186
has a friction surface
188
that, along with the peeling motion of the bottom edge of the top printing plate
18
1
, ensures that only one printing plate
18
at a time is picked off of the stack
20
. The lip
186
may be formed as a single unit, or using a plurality of lip segments that are spaced apart along the bottom edge of the cassette
22
. An exemplary embodiment of such a lip segment
194
is illustrated in
FIGS. 17 and 18
. In particular, the lip segment
194
includes a friction surface
188
that is formed using a plurality of serrated teeth
196
. The serrated teeth
196
are configured to rub against the bottom of a printing plate
18
as the printing plate
18
is peeled off of the stack
20
of printing plates
18
in the cassette
22
in direction
198
. As shown in
FIG. 18
, the serrated teeth
196
may be situated on a plane that is oriented at an angle (e.g., 5-9 degrees) with respect to the bottom of the stack of printing plates. Other types of friction surfaces
188
may also be used in the practice of the present invention.
As illustrated in
FIG. 14
, the first drive system
166
displaces the peeler
162
and the suction cups
116
away from the stack
20
as indicated by directional arrow
190
to peel the top printing plate
18
1
further off of the stack
20
. The top printing plate
18
1
is peeled off of the stack
20
a sufficient distance to provide clearance for the plate feed beams
110
of the printing plate supporting and feeding system
104
(FIG.
6
). The top printing plate
18
1
, which now rests on the plate feed beams of the printing plate supporting and feeding system (not shown), is displaced (
FIG. 15
) by the second drive system
170
toward the nip rollers
128
as indicated by directional arrow
192
. Finally, as shown in
FIG. 16
, the piston
148
of the pneumatic cylinder
150
is extended to position the bottom edge of the top printing plate
18
1
above the center of the nip rollers
128
. The input nips
128
direct the top printing plate
18
1
to a plate mounting system (not shown) that is configured to mount the top printing plate
18
1
onto the external drum
24
of the external drum platesetter
16
for subsequent imaging (FIG.
8
). The above process can be repeated to pick and peel each remaining printing plate
18
off of the stack
20
.
The foregoing description of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and many modifications and variations are possible in light of the above teaching. Such modifications and variations that may be apparent to a person skilled in the art are intended to be included within the scope of this invention.
Claims
- 1. An apparatus, comprising:a plurality of suction cups; an arc-shaped peeler; and a system for rotatably displacing the suction cups relative to the arc-shaped peeler; wherein a center line of rotation of the displacing system is located at a mid-point of an outer surface of the arc-shaped peeler.
- 2. The apparatus of claim 1, wherein the displacing system comprises:a platform; an angled bar having a plurality of wheels, wherein the suction cups are coupled to the angled bar; a curved slot formed in the platform, wherein the wheels of the angled bar are located within the curved slot; and a drive system for displacing the angled bar along the curved slot, wherein a displacement of the angled bar results in a rotation of the suction cups relative to the arc-shaped peeler.
- 3. The apparatus of claim 2, wherein the curved slot comprises a segment of a circle.
- 4. The apparatus of claim 2, wherein the drive system comprises a pneumatic cylinder.
- 5. The apparatus of claim 4, further comprising:a pin for rotatably coupling an end of a piston of the pneumatic cylinder to the angled bar.
- 6. The apparatus of claim 4, further comprising:a pin for rotatably coupling the pneumatic cylinder to the platform.
- 7. The apparatus of claim 1, further comprising:a stack of printing plates, wherein the suction cups and the peeler contact a surface of a top printing plate on the stack, and wherein the center line of rotation of the displacing system is located at a contact point between the arc-shaped peeler and the surface of the top printing plate.
- 8. The apparatus of claim 7, further comprising:a vacuum source for providing a vacuum to the suction cups to secure the suction cups to the surface of the top printing plate.
- 9. The apparatus of claim 7, wherein the displacing system displaces the suction cups away from the stack of printing plates, thereby peeling a portion of the top printing plate off of an underlying printing plate on the stack.
- 10. An apparatus for picking a printing plate from a stack of printing plates, comprising:a plurality of suction cups; an arc-shaped peeler; a drive system for displacing the suction cups and the arc-shaped peeler against a surface of a top printing plate on the stack; a vacuum source for supplying a vacuum to the suction cups to secure the suction cups against the surface of the top printing plate; and a system for rotatably displacing the suction cups relative to the arc-shaped peeler to peel a portion of the top printing plate off of the stack, wherein a center line of rotation of the displacing system is located at a contact point between the arc-shaped peeler and the surface of the top printing plate.
- 11. The apparatus of claim by 10, wherein the center line of rotation of the displacing system is located at a mid-point of an outer surface of the arc-shaped peeler.
- 12. The apparatus of claim 10, wherein the displacing system comprises:a platform; an angled bar having a plurality of wheels, wherein the suction cups are coupled to the angled bar; a curved slot formed in the platform, wherein the wheels of the angled bar are located within the curved slot; and a second drive system for displacing the angled bar along the curved slot, wherein a displacement of the angled bar results in a rotation of the plurality of suction cups relative to the arc-shaped peeler.
- 13. The apparatus of claim 12, wherein the curved slot comprises a segment of a circle.
- 14. The apparatus of claim 12, wherein the second drive system comprises a pneumatic cylinder.
- 15. The apparatus of claim 14, further comprising:a pin for rotatably coupling an end of a piston of the pneumatic cylinder to the angled bar.
- 16. The apparatus of claim 14, further comprising:a pin for rotatably coupling the pneumatic cylinder to the platform.
- 17. The apparatus of claim 10, wherein the second drive system displaces the suction cups, the peeler, and the top printing plate that is secured to the suction cups away from the stack.
- 18. The apparatus of claim 17, further comprising:a displacing system for displacing the top printing plate that is secured to the suction cups toward a pair of nip rollers.
- 19. The apparatus of claim 10, further comprising:a plate rest for supporting the stack of printing plates, wherein the plate rest includes a friction surface.
- 20. The apparatus of claim 19, wherein the friction surface comprises a plurality of serrated teeth.
- 21. The apparatus of claim 20, wherein the serrated teeth are situated on a plane that is oriented at an angle with respect to a bottom of the stack of printing plates.
- 22. A method for picking a printing plate from a stack of printing plates, comprising:displacing a plurality of suction cups and a peeler against a surface of a top printing plate on the stack; supplying a vacuum to the suction cups to secure the suction cups against the surface of the top printing plate; and rotatably displacing the suction cups relative to the peeler to peel a portion of the top printing plate off of the stack, wherein a center line of rotation of the displacement is located at a contact point between the peeler and the surface of the top printing plate.
- 23. A method for picking a printing plate from a stack of printing plates, comprising:displacing a plurality of suction cups and a peeler against a surface of a top printing plate on the stack; supplying a vacuum to the suction cups to secure the suction cups against the surface of the top printing plate; and peeling a portion of the top printing plate off of the stack, and preventing relative motion of the top printing plate against an underlying printing plate on the stack, by rotatably displacing the suction cups relative to the peeler, wherein a center line of rotation of the displacement is located at a contact point between the peeler and the surface of the top printing plate.
- 24. An apparatus, comprising:a plurality of suction cups; a peeler; and a system for rotatably displacing the suction cups relative to the peeler, the displacing system including a platform, an angled bar having a plurality of wheels, wherein the suction cups are coupled to the angled bar, a curved slot formed in the platform, wherein the wheels of the angled bar are located within the curved slot, and a drive system for displacing the angled bar along the curved slot, wherein a displacement of the angled bar results in a rotation of the suction cups relative to the peeler; wherein a center line of rotation of the displacing system is located on a surface of the peeler.
- 25. The apparatus of claim 24, wherein the peeler is arc-shaped.
- 26. The apparatus of claim 25, wherein the center line of rotation of the displacing system is located at a mid-point of the surface of the arc-shaped peeler.
- 27. The apparatus of claim 24, wherein the curved slot comprises a segment of a circle.
- 28. The apparatus of claim 24, wherein the drive system comprises a pneumatic cylinder.
- 29. The apparatus of claim 28, further comprising:a pin for rotatably coupling an end of a piston of the pneumatic cylinder to the angled bar.
- 30. The apparatus of claim 28, further comprising:a pin for rotatably coupling the pneumatic cylinder to the platform.
- 31. An apparatus for picking a printing plate from a stack of printing plates, comprising:a plurality of suction cups; a peeler; a drive system for displacing the suction cups and the peeler against a surface of a top printing plate on the stack; a vacuum source for supplying a vacuum to the suction cups to secure the suction cups against the surface of the top printing plate; and a system for rotatably displacing the suction cups relative to the peeler to peel a portion of the top printing plate off of the stack, the displacing system including a platform, an angled bar having a plurality of wheels, wherein the suction cups are coupled to the angled bar, a curved slot formed in the platform, wherein the wheels of the angled bar are located within the curved slot, and a second drive system for displacing the angled bar along the curved slot, wherein a displacement of the angled bar results in a rotation of the plurality of suction cups relative to the peeler, wherein a center line of rotation of the displacing system is located at a contact point between the peeler and the surface of the top printing plate.
- 32. The apparatus of claim 31, wherein the peeler is arc-shaped.
- 33. The apparatus of claim 32, wherein the center line of rotation of the displacing system is located at a mid-point of the surface of the arc-shaped peeler.
- 34. The apparatus of claim 31, wherein the curved slot comprises a segment of a circle.
- 35. The apparatus of claim 31, wherein the second drive system comprises a pneumatic cylinder.
- 36. The apparatus of claim 35, further comprising:a pin for rotatably coupling an end of a piston of the pneumatic cylinder to the angled bar.
- 37. The apparatus of claim 35, further comprising:a pin for rotatably coupling the pneumatic cylinder to the platform.
US Referenced Citations (6)
Foreign Referenced Citations (1)
Number |
Date |
Country |
3-288737 |
Dec 1991 |
JP |