Cylinder phase adjustment controlling apparatus for printing press

A cylinder phase adjustment controlling apparatus includes a plate cylinder gear, a reference point, a proximity switch, a rotary angle detector, a controller, and a counter. The plate cylinder gear is phase-adjustably fitted on a plate cylinder rotatably axially supported on a frame and coupled to a drive motor. The reference point rotates together with the plate cylinder. The proximity switch is fixed to the frame and detects the reference point. The rotary angle detector outputs a rotation pulse in accordance with rotation of the plate cylinder. The controller automatically controls the phase of the plate cylinder on the basis of an output from the rotary angle detector after the proximity switch detects the reference point. The counter counts the rotation pulse output from the rotary angle detector, and the controller stops rotation of the plate cylinder when the counter counts a predetermined number of rotation pulses corresponding to a control phase amount after a detection output is output from the rotary angle detector.

BACKGROUND OF THE INVENTION 
The present invention relates to a cylinder phase adjustment controlling 
apparatus for various types of printing presses, which performs control to 
automatically adjust the phase of a cylinder, e.g., a plate cylinder, in 
the circumferential direction when the specifications of a printed matter 
are changed or a plate is to be mounted on the cylinder. 
A sheet printing press with a reversing mechanism that can be convertibly 
used both for one-side printing and two-side printing is known as one type 
of a printing press. FIG. 3 shows the cylinder arrangement of a sheet 
printing press with a reversing mechanism of this type for explaining an 
one-side printing operation, and FIG. 4 shows the cylinder arrangement of 
the same for explaining a two-side printing operation. Referring to FIGS. 
3 and 4, a blanket cylinder 2 is provided under and in contact with an 
upstream plate cylinder 1 on which a plate is mounted. Similarly, a 
blanket cylinder 4 is provided under and in contact with a downstream 
plate cylinder 3 on which a plate is mounted. Reference numeral 5 denotes 
a double-diameter cylinder having a diameter twice that of the cylinder 1 
or 3. An impression cylinder 6 and a transfer cylinder 7 are disposed in 
contact with each other between the double-diameter cylinder 5 and the 
upstream blanket cylinder 2, and a reversing cylinder 8 and an impression 
cylinder 9 are disposed in contact with each other between the 
double-diameter cylinder 5 and the downstream blanket cylinder 4. 
Reference numeral 10 denotes a paper feed cylinder which is in contact 
with the upstream impression cylinder 6. 
Of these cylinders, the paper feed, impression, transfer, reversing, 
impression, and double-diameter cylinders 10, 6, 7, 8, 9, and 5 have 
gripper units (to be referred to as grippers hereinafter) 11, 12, 13, 14, 
15, 16, and 17 each made of an openable/closable gripper member and a 
gripper table. The grippers 11, 12, 13, 14, and 15 are disposed in the 
outer circumferential gaps of the paper feed, impression, transfer, 
reversing, and impression cylinders 10, 6, 7, 8, and 9. The grippers 16 
and 17 are disposed in the gaps formed at positions of the double-diameter 
cylinder 5 to equally divide the outer circumferential portion thereof 
into two portions in the circumferential direction. Reversing grippers 18 
having an arrangement the same as those of the above grippers are disposed 
in the outer circumferential gap of the reversing cylinder 8 to be close 
to the grippers 14. Chuck heads 19 and 20 are provided at portions of the 
double-diameter cylinder 5 that equally divide the outer circumferential 
portion of the double-diameter cylinder into two portions. The chuck heads 
19 and 20 are ahead of the grippers 16 and 17, respectively, by 
predetermined angles in the rotating direction of the cylinder 5 indicated 
by an arrow in FIG. 4. The respective cylinders are coupled to each other 
and driven by cylinder gears provided at their shaft end portions, as will 
be described later. Reference numeral 21 denotes a feed board inclinedly 
supported between a paper feed unit (not shown) and the paper feed 
cylinder 10; and 22, paper fed onto the feed board 21. 
With this arrangement, in the case of one-side printing shown in FIG. 3, 
when the respective cylinders are rotated in the directions indicated by 
arrows, the paper 22 fed from the paper feed unit onto the feed board 21 
is gripped by the grippers 11 of the paper feed cylinder 10, conveyed by a 
predetermined angle by the rotation of the paper feed cylinder 10, 
transferred to the gripper 12 of the impression cylinder 6, and wound on 
the circumferential surface of the impression cylinder 6. Since an image 
formed on the plate surface of the plate cylinder 1 is transferred to the 
blanket cylinder 2, this image is transferred to the paper 22 passing 
between the blanket and impression cylinders 2 and 6, thereby performing 
printing of the first color. 
The printed paper 22 is transferred from the grippers 12 of the impression 
cylinder 6 to the grippers 13 of the transfer cylinder 7, then to the 
grippers 16 or 17 of the double-diameter cylinder 5, and wound on the 
upper circumferential surface of the double-diameter cylinder 5. As the 
double-diameter and reversing cylinders 5 and 8 are rotated, the wound 
paper 22 is transferred from the grippers 16 or 17 to the opposite 
grippers 14, and to the grippers 15 of the impression cylinder 9. At this 
time, since the image formed on the plate surface of the plate cylinder 3 
is transferred to the blanket cylinder 4, this image is transferred to the 
paper 22 passing between the blanket and impression cylinders 4 and 9, 
thereby performing printing of the second color. In this case, since the 
image from the upstream blanket cylinder 2 and the image from the 
downstream blanket cylinder 4 are transferred on the same surface of the 
paper 22, one-side printing is performed. The paper 22 subjected to 
one-side printing is conveyed to a following printing unit or paper 
discharge unit (not shown). 
The operation of two-side printing will be described with reference to FIG. 
4. When one-side printing is switched to two-side printing, the whole 
upstream cylinder group including the double-diameter cylinder 5 is 
phase-adjusted by a phase adjusting unit (to be described later) with 
respect to the reversing cylinder 8, so that a state of FIG. 3 wherein the 
grippers 17 and 14 oppose each other is changed to a state of FIG. 4 
wherein the reversing grippers 18 oppose the chuck head 19 or 20. Also, 
the operation timings of the cam mechanisms for opening/closing the 
grippers 16 and 17 are adjusted. When the respective cylinders are rotated 
to start the printing operation, the paper 22 having a printed surface is 
transferred to the grippers 16 or 17 of the double-diameter cylinder 5, in 
the same manner as in the case of one-side printing, and wound on the 
upper circumferential surface of the double-diameter cylinder 5. 
In this case, after the grippers 16 or 17 pass over the contact points of 
the double-diameter and reversing cylinders 5 and 8, the two cylinders 5 
and 8 continue rotation. Then, the paper 22 wound on the upper 
circumferential surface of the double-diameter cylinder 5 is wound on the 
lower circumferential surface of the double-diameter cylinder 5, as 
indicated by a reference symbol 22A in FIG. 4. While the paper trailing 
end of the paper 22A is located at the contact point of the 
double-diameter and reversing cylinders 5 and 8, the reversing gripper 18 
of the reversing cylinder 8 is opened and closed. Thus, the paper trailing 
end of the paper 22A is gripped by the reversing grippers 18 by the 
cooperation of the reversing grippers 18 and the opposite chuck head 19 or 
20. As a result, the lower surface of the paper 22A is brought into 
contact with the circumferential surface of the reversing cylinder 8, and 
the upper surface of the paper 22A is brought into contact with the 
circumferential surface of the impression cylinder 9. Printing is 
performed on the lower surface of the paper 22A passing between the 
blanket and impression cylinders 4 and 9. Since printing has been 
performed on the upper surface of the paper 22 by the blanket cylinder 2, 
two-side printing is eventually performed. 
The conventional phase adjusting unit for adjusting the phases of the 
upstream cylinder group including the double-diameter cylinder 5 when 
one-side printing is switched to two-side printing, as described above, 
will be described. Referring to FIG. 3, the respective cylinders are 
coupled and driven by cylinder gears provided to their shaft end portions. 
Of these cylinder gears, the cylinder gear of the reversing cylinder 8 is 
constituted by stationary and pivot gears that are coupled to each other 
to be freely fixed or released with or from each other. The stationary 
gear of the cylinder gear of the reversing cylinder 8 is fixed to the end 
shaft of the reversing cylinder 8 and meshed with the cylinder gear of the 
impression cylinder 9, and the rotational gear thereof is meshed with the 
cylinder gear of the double-diameter cylinder 5. 
With this arrangement, when one-side printing is to be switched to two-side 
printing, the stationary and pivot gears are released from each other, and 
the pivot gear is pivoted by, e.g., a handle. Then, the cylinders 5, 7, 6, 
2, 1, and 10 of the upstream printing cylinder group including the 
double-diameter cylinder 5 are simultaneously pivoted by meshing of their 
cylinder gears, and their phases in the circumferential directions with 
respect to the reversing cylinder 8 are adjusted. Then, the stationary and 
pivot gears of the cylinder gear of the reversing cylinder 8 are fixed, 
thereby completing phase adjustment. 
In the case of two-side printing, the position of a pattern printed on the 
upper surface of the paper 22 and the position of a pattern printed on the 
lower surface of the paper 22 are misregistered from each other depending 
on the printing or mounting position of the plate. Furthermore, in 
two-side printing, printing is sometimes performed by intentionally 
misregistering the pattern position of the upper surface and the pattern 
position of the lower surface of the paper 22. For this purpose, as shown 
in FIG. 3, a cylinder gear 23 of the plate cylinder 1 is fitted on an end 
shaft 1a thereof by a bolt or the like to be freely fixed or released with 
or from it, and the cylinder gear 23 is meshed with a cylinder gear 25 of 
the impression cylinder 6 through a cylinder gear 24 of the blanket 
cylinder 2. The cylinder gear 25 of the impression cylinder 6 is meshed 
with a gear 26, and a gear 27 integrally fixed with the gear 26 is meshed 
with a gear 29 fixed to a rotary encoder 28 for outputting a rotation 
pulse to a controller (not shown). 
With this arrangement, when the bolt for fixing the cylinder gear 23 of the 
plate cylinder 1 is loosened to pivot and adjust the plate cylinder 1 and 
this fixing bolt is fixed, vertical registration of the plate is adjusted. 
Also, for example, when the plate cylinder 1 is to be stopped at a 
predetermined position for plate exchange or the like, the plate cylinder 
1 is driven by a motor, so that the stop position of the plate cylinder 1 
is controlled with reference to an output from the rotary encoder 28 
connected to the controller. 
In the conventional cylinder phase adjustment controlling apparatus, 
however, the phases of the cylinders are adjusted with reference to the 
output from the rotary encoder 28, as described above. Therefore, when 
phase adjustment is performed by changing the phases of, e.g., the plate 
cylinder 1 and the cylinder gear 23, the phase of the plate cylinder 1 
cannot be detected from the output from the rotary encoder 28, and the 
stop position of the plate cylinder 1 is shifted from the preset position 
by a moving adjustment amount. Then, the phase adjustment of the plate 
cylinder 1 cannot be controlled at a timing of the printing press side, so 
that the phase adjustment precision is degraded, and the preparation time 
is prolonged by readjustment, resulting in degradation in operability of 
the machine. These problems arise not only in the sheet printing press 
with the reversing mechanism described above, but also in a conventional 
one-side multi-color printing press, since the phases of the plate 
cylinder and cylinder gears are shifted from each other for registration 
of different colors. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide a cylinder phase 
adjustment controlling apparatus for a printing press capable of 
controlling phase adjustment on the basis of a cylinder reference 
regardless of the timing of the printing press side. 
It is another object of the present invention to provide a cylinder phase 
adjustment controlling apparatus for a printing press in which the quality 
of a printed matter and the operability of the printing press are 
improved. 
In order to achieve the above objects, according to the present invention, 
there is provided a cylinder phase adjustment controlling apparatus 
comprising a first gear phase-adjustably fitted on a cylinder rotatably 
axially supported on a frame and coupled to a drive motor, a 
to-be-detected body rotating together with the cylinder, detecting body, 
fixed to the frame, for detecting the to-be-detected body, a rotary angle 
detector for outputting a rotation pulse in accordance with rotation of 
the cylinder, and control means for automatically controlling a phase of 
the cylinder on the basis of an output from the rotary angle detector 
after the detecting body detects the to-be-detected body.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIGS. 1 and 2 show an embodiment in which the present invention is applied 
to a sheet printing press with a reversing mechanism, in which FIG. 1 
shows the end shaft portion of a plate cylinder, and FIG. 2 shows the 
plate cylinder and the arrangement of a phase adjustment controlling 
apparatus. Since the cylinder arrangement of the printing press is the 
same as those shown in FIGS. 3 and 4, a detailed description thereof will 
be omitted. 
As shown in FIGS. 1 and 2, a plate cylinder 1 having a cylinder arrangement 
shogun in FIGS. 3 and 4 is rotatably axially supported by a frame 30 
through a bearing 31. A plate cylinder gear 34 meshing with a blanket 
cylinder gear 33 fixed to the end shaft of a blanket cylinder 2 is 
rotatably fitted in a cylindrical gear holder 32 fixed to an end shaft 1a 
of the plate cylinder 1 by a bolt. A plurality of arcuated elongated holes 
34a having steps in the axial direction are formed in the inner surface of 
the plate cylinder gear 34, i.e., in the surface of the plate cylinder 
gear 34 facing the plate cylinder 1. An adjustment gear 35 is mounted on 
the outer side of the plate cylinder gear 34 and fixed by the gear holder 
32. The phase of the adjustment gear 35 relative to that of the plate 
cylinder gear 34 can be movably adjusted in the circumferential direction 
by clamping the screw portion of a bolt 36 inserted in a bolt hole 35a of 
the adjustment gear 35 in an arbitrary arcuated elongated hole 34a. 
A gear 40 meshing with the adjustment gear 35, and a handle 41 are 
integrally fixed and fitted on a stud 38, provided to stand on the counter 
plate cylinder side of the frame 30, to be pivotal and movable in the 
axial direction. After the bolt 36 is loosened, the gear 40 is axially 
moved, together with the handle 41, to the position shown in FIG. 1 to be 
meshed with the adjustment gear 35, and the handle 41 is pivoted. Then, 
the phase of the plate cylinder 1 integral with the adjustment gear 35 and 
the phase of the plate cylinder gear 34 relative to each other can be 
adjusted through the gear 40 in the circumferential direction. Reference 
numeral 42 denotes a disk fixed on the outer side of the adjustment gear 
35. The thrust of a shaft portion 43 of the disk 42 is supported by a 
thrust bearing 44 of the printing press so that the disk 42 is rotatably 
axially supported. 
In this apparatus, as shown in FIG. 2, an L-shaped reference point 46 
constituted by, e.g., an L-shaped reflecting plate is fixed on the outer 
circumferential portion of a stationary gear 45 of the plate cylinder 1 
and serves as a body to be detected. A proximity switch 47 constituted by, 
e.g., a photoelectric sensor is provided on the printing press and serves 
as a detecting body for moving close to the rotating locus of the 
reference point 46 and detecting light reflected by the reference point 
46. The output of the proximity switch 47 is connected to the reset input 
of a positioning counter 49 through a selector switch 50. A rotary encoder 
48 for outputting a large number of rotation pulses per revolution of the 
plate cylinder 1 is fixed on the printing press and serves as a rotary 
angle detector. The output of the rotary encoder 48 is connected, through 
a line 51, to the count input of the positioning counter 49 indicating the 
rotational angle (phase). The positioning counter 49 is connected to a 
controller 53, and the controller 53 outputs a control signal 54, e.g., a 
stop signal, to the printing press. Reference numeral 52 denotes a line 
for performing phase adjustment of other plate cylinders. 
The operation of the sheet printing press with the reversing mechanism 
having the above arrangement will be described. As the one-side printing 
operation and the two-side printing operation are described above, a 
repeated description thereof will be omitted. Only a switching operation 
between one-side printing and two-side printing will be described with 
reference to FIGS. 3 and 4. In order to perform the switching operation 
between one-side printing and two-side printing, the stationary and pivot 
gears fixed to the shaft end portion of a reversing cylinder 8 are 
released from each other, and the pivot gear is pivoted by, e.g., a 
handle. Then, cylinders 5, 7, and 6, the gears 2 and 1, and a gear 10 of 
the upstream printing cylinder group including a double-diameter cylinder 
5 are simultaneously rotated upon meshing of their cylinder gears, and 
their phases in the circumferential direction with respect to that of the 
reversing cylinder 8 are adjusted. Then, the stationary and pivot gears 
are fixed with each other, thereby completing phase adjustment of the 
printing press. 
In this state, when the phase of the plate cylinder 1 is to be singly 
adjusted, the bolt 36 is loosened, and the handle 41 is pivoted to pivot 
the gear 40 integral with it. Then, the phases of the plate cylinder and 
adjustment gears 34 and 35 relative to each other are changed in the 
circumferential direction while moving the bolt 36 in the corresponding 
arcuated elongated hole 34a of the plate cylinder gear 34, so that the 
phase of the plate cylinder 1 integral with the adjustment gear 35, and 
the phase of the plate cylinder gear 34 relative to each other are 
adjusted in the circumferential direction. After adjustment is completed, 
the bolt 36 is clamped to fix the plate cylinder and adjustment gears 34 
and 35. 
After the phase adjustment of only the plate cylinder 1 is performed, in 
the automatic phase control operation of the plate cylinder 1 necessitated 
by, e.g., plate mounting, the controller 53 detects the reference point 46 
from the output from the proximity switch 47, and moves the plate cylinder 
1 to the preset position with reference to the position of the reference 
point 46 on the basis of the output from the rotary encoder 48. More 
specifically, after the controller 53 detects the reference point 46, the 
positioning counter 49 counts a predetermined number of rotation pulses 
corresponding to the phase adjustment amount at the timings of the 
printing press side. Then, the controller 53 detects that the count of the 
positioning counter 49 coincides with the count stored in advance, and 
outputs a control signal 54 to stop rotation of the plate cylinder 1. 
Hence, since the plate cylinder 1 and the reference point 46 will not be 
deviated from each other even when the phase of the plate cylinder 1 is 
singly adjusted in the vertical direction, accurate phase control can be 
performed by detecting the reference point 46. In this case, the 
positioning counter 49 is reset by the output from the proximity switch 
47, and control can be easily performed by setting the reference position 
of the automatic phase adjustment operation of the plate cylinder 1 
necessitated by, e.g., plate mounting. More specifically, since the 
positioning counter 49 after being reset functions as the detector for 
detecting the rotational angle from the reference position, the count of 
the gear 40 directly indicates the phase amount. The count to be stored in 
correspondence with the phase adjustment amount with reference to the 
preset position may be fixed, or may be stored after the timing of the 
printing press is adjusted. 
In this embodiment, the reference point 46 is fixed on the end face of the 
stationary gear 45. However, the reference point 46 can be integrally 
fixed on the end face of the plate cylinder 1. In this embodiment, the 
reference point 46 serving as the body to be detected is fixed on the side 
surface of the upstream plate cylinder 1 in the paper convey direction. 
However, the reference point 46 can be fixed to the side surface of the 
downstream plate cylinder 3 or the like. In this embodiment, the present 
invention is applied to the plate cylinder of the sheet printing press 
with the reversing mechanism. However, the present invention is not 
limited to this, and can similarly be applied to a plate cylinder in a 
case wherein the plate cylinder is to be pivoted to a selected position 
and stopped for o plate exchange or the like. The cylinder to which the 
present invention is applied is not limited to a plate cylinder, but can 
similarly be applied to any other cylinder while obtaining the same effect 
as far as it is a cylinder the phase of which is to be changed. 
In this embodiment, the gear 40 is pivoted by manually rotating the handle 
41. However, the gear 40 can be rotated by a drive unit, e.g., a motor. 
As is apparent from the above description, according to the present 
invention, in a printing press having a cylinder rotatably axially 
supported on the frame and a gear rotation-adjustably fitted on this 
cylinder and coupled to the drive motor side, a body to be detected is 
integrally fixed on the cylinder, a detecting body for detecting this 
to-be-detected body is fixed on the printing press, and the detection 
output from the detecting body and the output from a rotary encoder are 
input to a control means. Therefore, phase adjustment of the cylinder can 
be performed without being influenced by the adjustment amount of the 
cylinder in the circumferential direction which is independent of the 
adjustment of the timing of the printing press. Thus, accurate control can 
be quickly performed, thereby improving the quality of the printed matter 
and the operability of the printing press.