Information
-
Patent Grant
-
6601504
-
Patent Number
6,601,504
-
Date Filed
Monday, June 25, 200123 years ago
-
Date Issued
Tuesday, August 5, 200320 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Blakely, Sokoloff, Taylor & Zafman
-
CPC
-
US Classifications
Field of Search
US
- 101 137
- 101 139
- 101 140
- 101 143
- 101 144
- 101 145
- 101 177
- 101 182
- 101 184
- 101 185
- 101 216
- 101 218
- 101 247
- 101 248
-
International Classifications
-
Abstract
A cylinder apparatus for a rotary printing press includes a pair of inner bearings, an outer bearing, a pair of frames, a pair of cylinders, a motor, and a pair of abutting members. The pair of inner bearings rotatatively support two end shafts of at least one plate cylinder. The inner bearings have engaging projections. The outer bearing pivotally supports one of the inner bearings. The pair of frames are arranged to oppose each other through a predetermined distance, and pivotally support the outer bearing and the other one of the inner bearings. The pair of cylinders pivot the inner bearings supported by one of the frames and the outer bearing. The motor pivots the outer bearing supported by the other one of the frames. The pair of abutting members are supported by the frames. The engaging projections of the inner bearings abut against the pair of abutting members when the plate cylinder abuts against a blanket cylinder upon driving operation of the cylinders.
Description
BACKGROUND OF THE INVENTION
The present invention relates to a cylinder apparatus for a rotary printing press which adjusts throw-on and throw-off of cylinders in contact opposite to each other, and the skew of a cylinder.
In various types of multicolor rotary printing presses such as an offset printing press, if plates mounted on the plate cylinders are misregistered among printing units of a plurality of ink colors, the images of the respective ink colors are printed misregistered. In view of this problem, a cylinder apparatus for a rotary printing press of this type has a plate registration unit for adjusting register of plates. U.S. Pat. No. 5,311,817 (reference
1
) discloses a cylinder apparatus for a rotary printing press of this type. According to U.S. Pat. No. 5,311,817, both end shafts of a plate cylinder
66
are rotatably supported by the right and left frames
51
through the eccentric bearings
67
, and the piston rods
70
of the cylinders
69
are connected to the eccentric bearings
67
. The plate cylinder
66
is moved into contact with, and away from, the rubber blanket cylinders
53
by rotating the eccentric bearings
67
by making the piston rods
70
move forward and backward. Further, the eccentric cam
71
restricting the amount of revolution of the eccentric bearing
67
rotates by operating together with the position adjustment of the rubber blanket cylinder
53
when the thickness of a sheet is changed. As a result, the printing pressure of the rubber blanket cylinder
53
and the plate cylinder
66
becomes constant, regardless of the position of the rubber blanket cylinder
53
.
The object of the present invention is to provide a drum unit of a rotary printing press, which has improved the printing quality by preventing clattering of a plate cylinder during the printing operation, by enabling to make a twist adjustment.
However, according to such a conventional unit, there has been a problem of not being able to make a plate registration by moving and adjusting one minor axis only of a plate cylinder, which is a so-called twisting adjustment.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a cylinder apparatus for a rotary printing press which improves printing quality.
In order to achieve the above object, according to the present invention, there is provided a cylinder apparatus for a rotary printing press, comprising a pair of first eccentric bearings for rotatatively supporting two ends of at least one first cylinder, the first eccentric bearings having abutting portions, a second eccentric bearing for pivotally supporting one of the first eccentric bearings, a pair of support members arranged to oppose each other through a predetermined distance and adapted to pivotally support the second eccentric bearing and the other one of the first eccentric bearings, a pair of first driving means for pivoting the first eccentric bearings supported by one of the support members and the second eccentric bearing, second driving means for pivoting the second eccentric bearing supported by the other one of the support members, and a pair of abutting members which are supported by the support members and against which the abutting portions of the first eccentric bearings abut when the first cylinder abuts against a second cylinder upon driving operation of the first driving means.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a developed partially cutaway front view of a cylinder apparatus for a rotary printing press according to an embodiment of the present invention;
FIG. 2A
is a view taken along the line of arrow IIA of
FIG. 1
, and
FIG. 2B
is a view taken along the line of arrow IIB of
FIG. 1
;
FIGS. 3A and 3B
are views taken along the lines of arrows IIA and IIB, respectively, of
FIG. 1
to show the second embodiment of the present invention;
FIG. 4
is a view showing another example of the engaging portion where the engaging projection of the inner bearing and the abutting portion abut; and
FIG. 5
is a side view showing the main part of a satellite type printing press to which the present invention is applied.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described in detail with reference to the accompanying drawings.
FIG. 1
shows a cylinder apparatus for a rotary printing press according to the first embodiment of the present invention. Referring to
FIG. 1
, a pair of frames
1
A and
1
B oppose each other through a predetermined gap. An outer bearing
3
serving as the second eccentric bearing is pivotally mounted in a bearing hole
2
A formed in the frame
1
A, and an inner bearing
4
serving as the first eccentric bearing is pivotally mounted on the outer bearing
3
. As shown in
FIG. 2B
, clearances
31
and
41
are set between the bearing hole
2
A and the outer surface of the outer bearing
3
and between the inner surface of the outer bearing
3
and the outer surface of the inner bearing
4
, respectively, and lubricating oil is to be supplied there, so that the outer and inner bearings
3
and
4
can pivot smoothly.
Referring to
FIG. 1
, an engaging projection
4
b
with a radially flat engaging surface
4
c
to abut against an abutting member
30
a
(to be described later) projects from the peripheral edge of a flange
4
a
in contact opposite to the inner surface of the frame
1
A of the inner bearing
4
. As shown in
FIG. 2B
, a forming direction A in which the engaging surface
4
c
of the engaging projection
4
b
is formed substantially coincides with the skew direction
40
of the plate cylinder
7
in which the plate cylinder
7
moves when the outer bearing
3
is pivoted.
The frame
1
B has a bearing hole
2
B. An inner bearing
6
serving as the first eccentric bearing is pivotally mounted in the bearing hole
2
B, and a clearance
61
is set between the outer surface of the inner bearing
6
and the bearing hole
2
B. An engaging projection
6
b
with a radially flat engaging surface
6
c
to abut against another abutting member
30
a
projects from a flange
6
a
in contact opposite to the inner surface of the frame
1
B of the inner bearing
6
. The plate cylinder
7
is arranged in contact opposite to a blanket cylinder
8
, and end shafts
7
A and
7
B of the plate cylinder
7
are rotatatively axially supported by the inner bearings
4
and
6
through bearings
9
. Axes C
1
of the inner bearings
4
and
6
are eccentric from an axis C of the plate cylinder
7
by t
1
, and an axis C
2
of the outer bearing
3
is eccentric from the axis C
1
of the inner bearing
4
by t
2
.
A pair of cylinders
11
A and
11
B are pivotally mounted on the inner surfaces of the frames
1
A and
1
B so as to oppose each other. Rods
12
A and
12
B of the cylinders
11
A and
11
B are pivotally mounted on pivotal mount portions
13
A and
13
B of those flanges
4
a
and
6
a
of the inner bearings
4
and
6
which are in contact with the inner surfaces of the frames
1
A and
1
B. As shown in
FIGS. 2A and 2B
, the pivotal mount portions
13
A and
13
B and the engaging projections
4
b
and
6
b
of the inner bearings
4
and
6
are positioned such that they are phase-shifted from each other by substantially 180° through the axis C of the plate cylinder
7
. The forward/backward moving directions of the rods
12
A and
12
B of the cylinders
11
A and
11
B are set substantially parallel to a line B that connects the axis C of the plate cylinder
7
and an axis C
3
of the blanket cylinder
8
. In
FIGS. 2A and 2B
, the inner bearings
4
and
6
and the outer bearing
3
are not shown.
In the cylinder apparatus with the above arrangement, referring to
FIGS. 2A and 2B
, when the rods
12
A and
12
B of the cylinders
11
A and
11
B move forward, the inner bearings
4
and
6
pivot around the end shafts
7
A and
7
B, respectively, of the plate cylinder
7
, so the plate cylinder
7
pivots about the axes C
1
of the inner bearings
4
and
6
as the pivot center. Upon pivot motion of the inner bearings
4
and
6
, when the engaging projections
4
b
and
6
b
abut against the abutting members
30
a
of corresponding cam shafts
30
(to be described later), the inner bearing
6
slightly pivots clockwise in
FIG. 2A
about the corresponding abutting member
30
a
as the pivot center. Accordingly, part of the outer surface of the inner bearing
6
serves as an urging portion
44
to urge part of the inner surface of the bearing hole
2
A of the frame
1
A. The urging portion
44
is located on the extension of the line B that connects the axis C
3
of the blanket cylinder
8
and the axis C of the plate cylinder
7
.
Referring to
FIG. 2B
, the inner bearing
4
slightly pivots counterclockwise about the corresponding abutting member
30
a
as the pivot center. Accordingly, part of the outer surface of the inner bearing
4
serves as an urging portion
42
to urge part of the inner surface of the outer bearing
3
. At a portion indicated by
43
in
FIG. 2B
, part of the outer surface of the outer bearing
3
serves as an urging portion
43
to urge part of the inner surface of the bearing hole
2
A of the frame
1
A. The urging portions
42
and
43
are located on the extension of the line B that connects the axis C
3
of the blanket cylinder
8
and the axis C of the plate cylinder
7
. In other words, an urging direction D
1
with which the inner bearing
6
urges the bearing hole
2
B at the urging portion
44
, an urging direction D
2
with which the inner bearing
4
urges the outer bearing
3
at the urging portion
42
, and an urging direction D
3
with which the outer bearing
3
urges the bearing hole
2
A at the urging portion
43
coincide with the direction of the line B.
Referring to
FIG. 1
, a motor
15
is fixed to the frame
1
A through a stud. The motor
15
has a potentiometer
17
for detecting the rotational speed of a motor shaft
16
, and a gear
18
is axially mounted on the motor shaft
16
. The gear
18
meshes with a gear
21
axially mounted on a shaft
20
. The shaft
20
is rotatatively supported and its movement in the axial direction is regulated. A piece
22
threadably engages with a threaded portion formed at the distal end of the shaft
20
. The piece
22
is pivotally mounted on one end of a lever
23
. A transmission shaft
24
has an eccentric small-diameter portion
24
a
and large-diameter portion
24
b
, and is pivotally supported by a support member
25
fixed to the frame
1
A. The small-diameter portion
24
a
of the transmission shaft
24
is fitted and fixed in a hole formed in the other end of the lever
23
.
The large-diameter portion
24
b
of the transmission shaft
24
is fitted and fixed in a hole formed in one end of a lever
26
. The other end of the lever
26
is pivotally mounted on the flange of the outer bearing
3
. In this arrangement, when the motor
15
is driven and the rotation of the motor shaft
16
is transmitted to the shaft
20
through the gears
18
and
21
, the lever
23
is pivoted through the piece
22
about the transmission shaft
24
as the pivot center, so the transmission shaft
24
also pivots together with the lever
23
. Pivot motion of the transmission shaft
24
is transmitted to the lever
26
through the large-diameter portion
24
b
, so the lever
26
moves in the direction of arrows as shown in FIG.
2
B. Upon movement of the lever
26
, the outer bearing
3
pivots clockwise or counterclockwise in FIG.
1
. As the axis C
2
of the outer bearing
3
is eccentric from the axis C
1
of the inner bearing
4
, upon pivot motion of the outer bearing
3
, the plate cylinder
7
moves in the skew direction indicated by an arrow
40
in FIG.
2
B.
Referring to
FIG. 1
, cam shafts
30
are pivotally supported in the holes of the frames
1
A and
1
B through bushes
31
. One end of each of the cam shafts
30
respectively projecting from inside the frames
1
A and
1
B has the eccentric cam-shaped abutting member
30
a
. Disks
33
are pivotally supported by the bearings of the blanket cylinder
8
, and are pivotally adjusted by operation members (not shown). One end of each link
34
is pivotally mounted on a corresponding disk
33
, and one end of a corresponding lever
35
is pivotally mounted on the other end of this link
34
. The other end of the lever
35
is axially mounted on the other end of the corresponding one of the cam shafts
30
projecting outside the frames
1
A and
1
B. In this arrangement, when the disks
33
are pivotally adjusted, the cam shafts
30
pivot through the links
34
and levers
35
. Upon pivot motion of the cam shafts
30
, in
FIG. 2B
, the abutting position where the engaging projection
4
b
of the inner bearing
4
abuts against the corresponding abutting member
30
a
is adjusted, thereby adjusting the nip pressure between the plate cylinder
7
and blanket cylinder
8
.
The throw-on and throw-off operation of the plate cylinder
7
with respect to the blanket cylinder
8
in the cylinder apparatus for the rotary printing press with the above arrangement will be described.
When the rods
12
A and
12
B of the cylinders
11
A and
11
B move forward, the inner bearings
4
and
6
pivot around the end shafts
7
A and
7
B, as described above, so the plate cylinder
7
pivots about the axes C
1
of the inner bearings
4
and
6
as the pivot center. Upon pivot motion of the plate cylinder
7
, the engaging projections
4
b
and
6
b
abut against the abutting members
30
a
of the cam shafts
30
, and the inner bearing
4
is urged against the outer bearing
3
at the urging portion
42
. The outer and inner bearings
3
and
6
are urged against the bearing holes
2
A and
2
B at the urging portions
43
and
44
, respectively, so the plate cylinder
7
comes into contact opposite to the plate cylinder
7
with an appropriate nip pressure.
Therefore, during printing, when the notches of the plate cylinder
7
and plate cylinder
7
oppose each other and after that the outer surfaces of the plate cylinder
7
and blanket cylinder
8
come into contact opposite to each other again, so the plate cylinder
7
tries to slightly move in the direction of diameter of the blanket cylinder
8
, this movement is prohibited by the urging portions
42
,
43
, and
44
. Hence, the plate cylinder
7
and blanket cylinder
8
are regulated from generating vibration due to their movement, and accordingly printing errors can be prevented.
In addition, the urging portions
42
,
43
, and
44
are positioned to be located on the extension of the line B that connects the axis C
3
of the blanket cylinder
8
and the axis C of the plate cylinder
7
. At the urging portion
44
, the urging direction D
1
with which the inner bearing
6
urges the bearing hole
2
B coincides with the direction of the line B. At the urging portions
42
and
43
, the urging direction D
2
with which the inner bearing
4
urges the outer bearing
3
and the urging direction D
3
with which the outer bearing
3
urges the bearing hole
2
A coincide with the direction of the line B. Hence, as the direction of the movement of the plate cylinder
7
caused by the notches of the plate cylinder
7
and blanket cylinder
8
is from the axis C of the plate cylinder
7
toward the axis C
3
of the blanket cylinder
8
, that is, opposite to the urging directions D described above, the movement of the plate cylinder
7
is regulated. As a result, printing errors can be prevented more reliably.
If the skew direction of the plate cylinder
7
need be adjusted, the motor
15
is driven. Then, the rotation of the motor shaft
16
is transmitted to the shaft
20
through the gears
18
and
21
, and the lever
23
is pivoted through the piece
22
about the transmission shaft
24
as the pivot center. When the lever
23
pivots, the transmission shaft
24
also pivots together with it. Pivot motion of the transmission shaft
24
is transmitted to the lever
26
through the large-diameter portion
24
b
, and the lever
26
moves in the direction of arrows as shown in FIG.
2
B. Thus, the outer bearing
3
pivots clockwise or counterclockwise in
FIG. 1
, and the plate cylinder
7
moves in the skew direction indicated by the arrow
40
. At this time, since the skew direction
40
along which the plate cylinder
7
moves coincides with the forming direction A of the engaging surface
4
c
of the engaging projection
4
b,
during skew adjustment, the positional relationship between the inner bearing
4
and the end shaft
7
A of the plate cylinder
7
does not change. As a result, the nip pressure of the plate cylinder
7
with respect to the blanket cylinder
8
is appropriately maintained.
FIGS. 3A and 3B
show a cylinder apparatus according to the second embodiment of the present invention.
The second embodiment is different from the first embodiment described above in that the forward/backward moving directions of rods
12
A and
12
B of cylinders
11
A and
11
B are not parallel to a line B and that a forming direction A of an engaging surface
4
c
of an engaging projection
4
b
does not coincide with a skew direction
40
of a plate cylinder
7
.
In the cylinder apparatus with the above arrangement, when the rods
12
A and
12
B of the cylinders
11
A and
11
B are moved forward, inner bearings
4
and
6
pivot around end shafts
7
A and
7
B of the plate cylinder
7
. Upon pivot motion of the inner bearings
4
and
6
, when the engaging projection
4
b
and an engaging projection
6
b
abut against abutting members
30
a
, the inner bearings
4
and
6
slightly pivot about the abutting members
30
a
as the pivot centers. Hence, urging portions
42
,
43
, and
44
are formed at positions not on the extension of the line B.
In this case, if the driving forces of the cylinders
11
A and
11
B are set to a predetermined value or more, during printing, when the notch of the plate cylinder
7
and that of a blanket cylinder
8
oppose each other and the outer surfaces of the plate cylinder
7
and blanket cylinder
8
come into contact opposite to each other again, the plate cylinder
7
tries to slightly move in the direction of diameter of the blanket cylinder
8
. However, since the urging portions
42
,
43
, and
44
are formed, movement of the plate cylinder
7
is prohibited. Therefore, the plate cylinder
7
and blanket cylinder
8
are regulated from generating vibration due to their movement, and accordingly printing errors can be prevented.
In the above embodiments, the engaging surface
4
c
and an engaging surface
6
c
are formed on the engaging projections
4
b
and
6
b
, respectively. Alternatively, as shown in
FIG. 4
, an engaging surface
30
b
may be formed on the abutting member
30
a
. In this case, a pin
4
d
standing upward from the engaging projection
4
b
of the inner bearing
4
abuts against the engaging surface
30
b
of the abutting members
30
a
. While
FIG. 4
shows a modification of
FIG. 2B
, the same applies to FIG.
2
A.
FIG. 5
shows a case in which the present invention is applied to a satellite type printing press. In the satellite type printing press, four plate cylinders
7
are arranged like satellites around a pair of blanket cylinders
8
in contact opposite to each other, to perform multicolor printing simultaneously. In the satellite type printing press with this arrangement as well, if frames
1
A and
1
B, inner bearings
4
and
6
with engaging projections
4
b
and
6
b
, an outer bearing
3
, cylinders
11
A and
11
B, and abutting members
30
a
are provided to each plate cylinder
7
, the present invention can be applied to the printing press, in the same manner as described in the above embodiments.
As has been described above, according to the present invention, since part of the first eccentric bearing is urged against part of the second eccentric bearing, during printing, these eccentric bearings do not cause backlash, so printing errors can be prevented. When skew registration is adjusted, since the nip pressure of one cylinder with respect to the other cylinder is maintained at almost a constant value, the printing quality is improved. When the notches of the two cylinders oppose during printing, movement of the cylinders is regulated, so that printing errors can be prevented more reliably.
Claims
- 1. A cylinder apparatus for a rotary printing press, comprising:a pair of first eccentric bearings for rotatatively supporting two ends of at least one first cylinder, said first eccentric bearings having abutting portions; a second eccentric bearing for pivotally supporting one of said first eccentric bearings; a pair of support members arranged to oppose each other through a predetermined distance and adapted to pivotally support said second eccentric bearing and the other one of said first eccentric bearings; a pair of first driving means for pivoting said first eccentric bearings supported by one of said support members and said second eccentric bearing; second driving means for pivoting said second eccentric bearing supported by the other one of said support members; and a pair of abutting members which are supported by said support members and against which said abutting portions of said first eccentric bearings abut when said first cylinder abuts against a second cylinder upon driving operation of said first driving means, wherein throw-on and throw-off operations of the first cylinder to the second cylinder are performed by pivoting a pair of said first eccentric bearings, wherein skew adjustment of the first cylinder in relation to the second cylinder is performed by pivoting the second eccentric bearings, and wherein the abutting portions of the first eccentric bearings driven by the first driving means abut against said abutting members to form (1) a first urging portion from the other one of the first eccentric bearings to the support members, (2) a second urging portion from one of the first eccentric bearings to the second eccentric bearings and (3) a third urging portion from the second eccentric bearings to the support members.
- 2. An apparatus according to claim 1, wherein said abutting portions have abutting surfaces against which said abutting members abut, and the abutting surfaces are formed in substantially the same direction as a skew direction, wherein said skew direction is perpendicular to a line that connects axes of said first and second cylinders when the first and second cylinders are disposed substantially parallel with respect to each other.
- 3. An apparatus according to claim 1, wherein said second eccentric bearing pivots to skew said first cylinder in a skew direction that is perpendicular to a line that connects axes of said first and second cylinders when the first and second cylinders are disposed substantially parallel with respect to each other.
- 4. An apparatus according to claim 3, wherein said abutting a members have abutting surfaces against which the abutting portions abut, and the abutting surfaces are formed in substantially the same direction as the skew direction.
- 5. An apparatus according to claim 1, wherein the second urging portion from one of said first eccentric bearings toward said second eccentric bearing and the third urging portion from said second eccentric bearing toward the other one of said support members are substantially located on a line that connects two axes of said first and second cylinders.
- 6. An apparatus according to claim 5, wherein the first urging portion from the other one of said first eccentric bearings toward the other one of said support members is substantially located on a line that connects the two axes of said first and second cylinders.
- 7. An apparatus according to claim 1, whereinthe abutting portions comprise engaging projections projecting from outer surfaces of said first eccentric bearings, said abutting members comprises eccentric cams, and when said eccentric cams are pivotally adjusted, abutting positions where the engaging projections and said eccentric cams abut change to adjust a nip pressure between said first and second cylinders.
- 8. An apparatus according to claim 1, whereinsaid first cylinder comprises a plurality of first cylinders arranged around said second cylinder, and said first eccentric bearings with the abutting portions, said second eccentric bearing, said support members, said first and second driving means, and said abutting portions are provided to correspond to each of said plurality of first cylinders.
- 9. An apparatus according to claim 1, wherein said first cylinder is a plate cylinder, and said second cylinder is a blanket cylinder.
- 10. An apparatus according to claim 1, wherein the second eccentric bearing and the one of the first eccentric bearings form a double eccentric bearing assembly in which the second eccentric bearing is disposed outside of the one of the first eccentric bearings.
- 11. An apparatus according to claim 10, wherein the second eccentric bearing is pivotable with respect to the one of the first eccentric bearings to enable non-parallel adjustment of the first cylinder with respect to the second cylinder.
- 12. An apparatus for a rotary printing press having at least one plate cylinder and a blanket cylinder, comprising:a first bearing assembly coupled to a support member to rotatatively support a first end of the plate cylinder; a second bearing assembly coupled to the support member to rotatatively support a second end of the plate cylinder, said second bearing assembly including an inner bearing and an outer bearing disposed outside of the inner bearing, wherein the outer hearing of the second bearing assembly is pivotable with respect to the inner bearing to enable non-parallel adjustment of the plate cylinder with respect to the blanket cylinder; and abutting portions formed on said first and second bearing assemblies so as to cause (1) a portion of the first bearing assembly to press against the support member, (2) a portion of the inner bearing of the second bearing assembly to press against the outer bearing thereof, and (3) a portion of the outer bearing of the second bearing assembly to press against the support member, when the plate cylinder and the blanket cylinder are positioned for printing.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2000-189457 |
Jun 2000 |
JP |
|
US Referenced Citations (8)
Foreign Referenced Citations (1)
Number |
Date |
Country |
64-42135 |
Mar 1989 |
JP |