Cylinder apparatus for rotary printing press

Information

  • Patent Grant
  • 6601504
  • Patent Number
    6,601,504
  • Date Filed
    Monday, June 25, 2001
    23 years ago
  • Date Issued
    Tuesday, August 5, 2003
    20 years ago
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)
Number Name Date Kind
3786749 Vir Singh Jan 1974 A
4524712 Ito Jun 1985 A
4569306 Ito et al. Feb 1986 A
4833982 Liebert et al. May 1989 A
5311817 Funada May 1994 A
5320038 Fischer Jun 1994 A
5722323 Whiting et al. Mar 1998 A
6347585 Kiamco et al. Feb 2002 B1
Foreign Referenced Citations (1)
Number Date Country
64-42135 Mar 1989 JP