Information
-
Patent Grant
-
6227110
-
Patent Number
6,227,110
-
Date Filed
Tuesday, June 23, 199826 years ago
-
Date Issued
Tuesday, May 8, 200123 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 101 216
- 101 217
- 101 218
- 101 147
- 101 148
- 101 247
- 101 248
- 101 191
- 101 192
- 101 152
- 101 153
- 101 136
- 101 138
- 101 139
- 101 140
- 101 141
- 101 143
- 101 144
- 101 145
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International Classifications
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Abstract
An offset printing press for printing a web, the press comprising a frame, a first plate cylinder movably mounted in the frame, and a first blanket cylinder in selective contact with the first plate cylinder. A second blanket cylinder for forming a nip with the first blanket cylinder is in contact with a second plate cylinder. The press has a first operative condition wherein the first plate cylinder and the first blanket cylinder are in direct contact to permit double-sided printing on the web, and a second operative condition wherein the first plate cylinder and the first blanket cylinder are separated to permit a plate change on the first plate cylinder while the web is printed by the second blanket cylinder.
Description
FIELD OF THE INVENTION
The present invention relates to printing presses and more specifically to web-fed printing presses.
RELATED TECHNOLOGY
Certain web offset printing presses have a continuous paper web which may be printed on both sides. Typical offset web presses permitting double-sided printing do not permit for printing on one side of the web while a printing plate on the other side of the web is changed.
SUMMARY OF THE INVENTION
The present invention provides an offset printing press for printing a web, the press comprising a frame, a first plate cylinder moveably mounted in the frame and a first blanket cylinder in selective contact with the first plate cylinder. A second blanket cylinder is provided for forming a nip with the first blanket cylinder, the web being able to pass through the nip. A second plate cylinder contacts the second blanket cylinder and also may be moveably mounted in the frame. The press has a first operative condition wherein the first plate cylinder and the first blanket cylinder are in direct contact to permit double-sided printing on the web, a second operative condition wherein the first plate cylinder and the first blanket cylinder are separated to permit a plate change on the first plate cylinder while the web is printed by the second blanket cylinder, and may have a third operative condition wherein the second plate cylinder and the second blanket cylinder are separated while the web is printed by the first blanket cylinder.
The present invention thus advantageously provides an arrangement wherein plate changes may be performed while the web is still being printed on one side. This can reduce downtime and improve productivity of the press.
Advantageously, one of the blanket cylinders also may be movably mounted. In addition, the movably mounted cylinders advantageously can be pivotally mounted in the frame for simple and stable translational movement.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, the present invention is explained in more detail with the aid of the drawings, in which:
FIG. 1
shows a general view of an offset web printing press of the present invention;
FIG. 2
shows a detailed side view of one embodiment of the printing press of the present invention;
FIG. 3
shows a detailed side view of a second embodiment of the printing press of the present invention.
DETAILED DESCRIPTION
FIG. 1
shows a side view of an offset web printing press
100
having at least one print unit
110
with a frame
13
, a first plate cylinder
101
, a first blanket cylinder
102
, a second blanket cylinder
103
and a second plate cylinder
104
. A web
108
of paper passes through a nip formed between the first blanket cylinder and second blanket cylinder. For color printing it is understood that the printing press
100
would have a plurality, typically, four, of such print units.
The printing press
100
has three operative conditions: a first operative condition in which the web
108
is printed on both sides; a second operative condition in which the second plate cylinder
104
prints on one side of the web
108
through the second blanket cylinder
103
while the first plate cylinder
101
is disengaged from the first blanket cylinder
102
; and a third operative condition in which the first plate cylinder
101
prints on an other side of the web
108
through the first blanket cylinder
102
while the second plate cylinder
104
is disengaged from the second blanket cylinder
103
. Thus in the second operative condition a printing plate on the first plate cylinder
101
can be changed while printing continues on one side of the web
108
, and in the third operative condition a printing plate on the second plate cylinder
104
can be changed while printing occurs on the other side. These operative conditions can be simultaneous for each print unit of the printing press
100
.
FIG. 2
shows one embodiment of the printing press of the present invention in more detail. The plate cylinder
101
, the blanket cylinder
102
, the blanket cylinder
103
and the plate cylinder
104
of
FIG. 1
each have an end disposed in a first plate cylinder box
1
, a first blanket cylinder box
2
, a second blanket cylinder box
3
, and a second plate cylinder box
4
, respectively. Each of the cylinder boxes
1
,
2
and
4
are movably mounted in the frame
13
through pivots
7
,
8
, and
18
, respectively. The second blanket cylinder box
3
is however fixedly mounted to the frame
13
by bolts, including bolt
9
. It should be understood that on the other side of the cylinders
101
,
102
, and
104
, corresponding boxes (not shown) are mounted pivotally to support the other ends of the cylinders, while the other side of second blanket cylinder
103
has a corresponding second blanket cylinder box fixedly mounted to frame
13
.
To provide the three operative conditions, two air cylinders
5
and
6
may be provided. A first air cylinder
5
is connected at one side through a pivot
10
to the second plate cylinder box
4
, and at another side through a rod
114
to the frame
13
. The rod
114
has a rod end
14
mounted to a block
15
attached to the frame
13
. The rod end
14
has a slot which interacts with a pin
16
of the block
15
. The rod
114
passes through a hole in an arm
112
of the first blanket cylinder box
2
. A spring
17
interacts between a stop
117
fixed to the rod
114
and the arm
112
to force the arm away from the stop
117
. A second air cylinder
6
is attached at one end to the first plate cylinder box
1
through a pivot
11
and at the other end to a pivot
12
in the frame
13
.
In the first operative condition when both sides of the web are being printed, the air cylinder
6
forces the plate cylinder box
1
against a stop
119
on the blanket cylinder box
2
so that the plate cylinder
101
is in contact with the blanket cylinder
102
. The air cylinder
5
pulls the second plate cylinder box
4
to the fixed second blanket cylinder box
3
and the rod end
14
pulls the first blanket cylinder box
2
through arm
112
and against the action of spring
17
to the second blanket cylinder box
3
. All of the cylinders
101
,
102
,
103
and
104
are thus in contact and double sided printing can occur on the web
108
passing through the nip formed by the blanket cylinders
102
and
103
.
In the second operative condition, the second air cylinder
6
pulls the first plate cylinder box
1
so that the cylinder box
1
rotates about pivot
7
until the box
1
comes against a stop
19
. The plate cylinder
101
is thus no longer in contact with the blanket cylinder
102
, and a plate change can occur on the first plate cylinder
101
, even while printing by second plate cylinder
104
continues.
In the third operative condition, the second air cylinder
6
again pushes the first plate cylinder box
1
against the stop
119
so that the first plate cylinder
101
contacts the first blanket cylinder
102
. The first air cylinder
5
operates so that the rod end
14
pushes against the block
15
and simultaneously the second plate cylinder box
4
is pivoted about pivot
18
until blocked by a stop
20
. Since the second blanket cylinder box
3
is fixed to the frame
13
, the second plate cylinder
104
is thus separated from the second blanket cylinder
103
and a plate change may occur, even while printing by the first plate cylinder
101
occurs on another side of the web
108
.
In a non-operative or non-printing condition, the first and second air cylinders
5
,
6
operate so that the first plate cylinder box
1
is forced against stop
19
and the second plate cylinder box
4
is forced against stop
20
. The spring
17
then forces the first blanket cylinder box
2
to rotate about pivot
8
away from the second blanket cylinder box
3
until arm
112
contacts block
15
. In this way the two blanket cylinders
102
and
103
may be separated.
FIG. 3
shows a second embodiment of the present invention in which three air cylinders
22
,
25
and
28
are used to provide the three operative conditions. The second plate cylinder box
3
again is fixed, while the other cylinder boxes
1
,
2
and
4
are pivotally mounted to the frame by pivots
7
,
8
and
18
, respectively.
In the first operative condition the first air cylinder
22
, connected at one side to a pivot
23
and at the other side to a pivot
24
connected to an arm
112
of the cylinder box
2
, forces the cylinder box
2
against the cylinder box
3
. The second air cylinder
25
, connected at one end to the cylinder box
4
through pivot
26
and at the other end to a pivot
27
connected to the frame
13
, forces the cylinder box
4
against the cylinder box
3
. The third air cylinder
28
is connected to the frame
13
through pivot
29
and to the first plate cylinder box
1
through the pivot
30
. The third air cylinder
28
pulls the cylinder box
1
against a stop
119
in the first operative condition.
In the second operative condition, the third air cylinder
28
pushes the first plate cylinder box
1
away from the stop
119
so that a plate on the first plate cylinder
101
can be changed.
In the third operative condition, the third air cylinder
28
pulls the cylinder box
1
against the stop
119
while the second air cylinder
25
pulls the cylinder box
4
away from the cylinder box
3
.
In a non-printing or non-operative condition, the third air cylinder
28
pushes the first plate cylinder box
1
away from the pivot
29
and the first air cylinder
22
pulls the first blanket cylinder box
2
away from the second blanket cylinder box
3
.
“Movably mounted” as herein defined means being mounted so as to be translationally movable, and includes being pivotally mounted.
Claims
- 1. An offset printing press for printing a web, the press comprising:a frame; a first plate cylinder pivotally mounted in the frame; a first blanket cylinder movably mounted in the frame, the first blanket cylinder in selective contact with the first plate cylinder; a second blanket cylinder rotatably mounted and translationally fixed to the frame for forming a nip with the first blanket cylinder, the web being able to pass through the nip; and a second plate cylinder pivotally mounted to the frame for contacting the second blanket cylinder; a first air cylinder connected to the first blanket cylinder and the second plate cylinder; a second air cylinder connected to the first plate cylinder; the press having a first operative condition wherein the first plate cylinder and the first blanket cylinder are in direct contact to permit double-sided printing on the web; a second operative condition wherein the first plate cylinder and the first blanket cylinder are separated to permit a plate change on the first plate cylinder while the web is printed by the second blanket cylinder; third operative condition wherein the second plate cylinder and the second blanket cylinder are separated while the web is printed by the first blanket cylinder and a non-printing condition in which the first blanket cylinder is separated from the second blanket cylinder.
- 2. The offset printing press as recited in claim 1 further comprising a first plate cylinder box, the second air cylinder being connected to the first plate cylinder through the first plate cylinder box.
- 3. The offset printing press as recited in claim 1 further comprising a first plate cylinder box, a first blanket cylinder box, and a second plate cylinder box, the first air cylinder being connected to the first blanket cylinder through the first blanket cylinder box and to the second plate cylinder through the second plate cylinder box, and the second air cylinder being connected to the first plate cylinder through the first plate cylinder box.
- 4. An offset printing press for printing a web, the press comprising:a frame; a first plate cylinder movably mounted in the frame; a first blanket cylinder in selective contact with the first plate cylinder and being pivotally mounted in the frame; a first air cylinder connected to the first blanket cylinder and the second plate cylinder; a second blanket cylinder for forming a nip with the first blanket cylinder, the web being able to pass through the nip; and a second plate cylinder for contacting the second blanket cylinder and being moveably mounted in the frame, the press having a first operative condition wherein the first plate cylinder and the first blanket cylinder are in direct contact to permit double-sided printing on the web; a second operative condition wherein the first plate cylinder and the first blanket cylinder are separated to permit a plate change on the first plate cylinder while the web is printed by the second blanket cylinder; and a third operative condition wherein the second plate cylinder and the second blanket cylinder are separated while the web is printed by the first blanket cylinder.
- 5. The offset printing press as recited in claim 4 wherein the first plate cylinder is pivotally mounted to the frame.
- 6. The offset printing press as recited in claim 4 wherein the second plate cylinder is pivotally mounted in the frame.
- 7. The offset printing press as recited in claim 4 wherein the second blanket cylinder is rotatably mounted but translationally fixed in the frame.
- 8. The offset printing press as recited in claim 4 further comprising and a second air cylinder connected to the frame and the first plate cylinder.
- 9. The offset printing press as recited in claim 8 wherein the first air cylinder is connected to the first blanket cylinder through a spring.
US Referenced Citations (7)
Foreign Referenced Citations (2)
Number |
Date |
Country |
2216514 |
Oct 1973 |
DE |
2 309 668 |
Jun 1997 |
GB |