JPH0312516Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a paper reversing device for reversing paper between adjacent cylinders in order to perform double-sided printing in a sheet-fed rotary printing press.

[Prior art]

With the diversification of printing, various sheet-fed rotary printing machines equipped with reversing devices that can be used for single-sided printing and double-sided printing have been proposed and put into practical use.
Although these types differ in the number and arrangement of cylinders and the structure of the paper reversing device used for double-sided printing, the principle of paper reversing is the same for all of them. In other words, this type of printing press is equipped with a cylinder equipped with a non-reversing claw and a cylinder equipped with a reversing claw, with their circumferential surfaces facing each other. Stop the machine and change the paper in the mouth in the same way as for general single-sided printing. In the case of double-sided printing, the phases of both cylinders are shifted in the circumferential direction by the length of the paper so that the trailing edge of the paper gripped by the claws of the upstream cylinder faces the reversing claws of the downstream cylinder. The end of the paper is held in a reversing claw and conveyed as the cylinder rotates, thereby reversing the paper and printing on the back side with the next printing cylinder to perform double-sided printing.

During such double-sided printing, when the tail of the paper to be reversed faces the reversing claw, if the trailing edge of the paper is on the upstream side of the cylinder and is away from the reversing claw, the trailing edge of the paper may be caught in the reversing claw. Therefore, the reversing cylinder is generally equipped with a suction device that suctions the end of the paper toward the reversing claw. This suction device includes a suction head connected to an air source via a rotary valve, and suctions air through suction holes opened in the end face of the suction head to suction paper. It is provided on another axis close to and parallel to the axis of the reversing pawl, and located intermediate between the reversing pawls. Therefore, in such conventional devices, when the suction head suctions the trailing edge of the paper and causes it to be held in the reversing claw, even if the reversing claw grips the edge of the paper, the suction head moves from the edge of the paper to one end of the reversing claw. The inside part will be suctioned by 2 pitches, and depending on the grip position of the reversing claw, in the worst case, the inside part will be sucked by approximately 1 pitch of the reversing claw from the edge of the paper and the reversing claw will hold it in its mouth. As a result, paper rips easily occur, and when severe, paper folds occur. Even if the gripping position of the reversing claw shifts slightly as a result of the paper being scratched, this will be magnified at the end of the paper, resulting in a large misregistration, resulting in paper waste or a significant deterioration in the quality of printed matter. Also, this is because the pitch between adjacent suction heads is wide, not only at the edge of the paper but also at the center in the width direction of the paper, so the paper is scraped by the tilting when it is sucked and placed in the reversing claw, and the same misregistration occurs. This was a factor that deteriorated the quality of printed matter.

[Summary of the idea]

The present invention was developed in view of the above points, and is an auxiliary device in which the suction port is formed coaxially with the suction lever that causes the reversing claw to hold the paper in its mouth, and the suction part is formed with a narrow width in the vertical direction of the paper so as not to interfere with the reversing claw. The suction lever is provided in almost the same phase as the reversing claw in the axial direction, and the air suction holes in the suction ports of at least the auxiliary suction levers of some of the auxiliary suction levers located at both ends in the paper width direction and the existing suction levers are installed in the paper width direction. By opening only approximately half of the paper near the center, it is possible to firmly support and adsorb paper edges of various sizes with different left and right edge positions without air leakage. The present invention provides a paper reversing device for a sheet-fed rotary printing press that aims to improve the quality of printed matter by increasing the registration accuracy by increasing the suction force at a certain point and preventing paper from fraying. Embodiments of the present invention will be described in detail below with reference to the drawings.

〔Example〕

1 to 9 show an embodiment of the paper reversing device according to the present invention, FIG. 1 is a cylinder arrangement diagram of a sheet-fed rotary printing press in which this is implemented, and FIG. 2 is a partially broken view of the paper reversing device. Side view, Figure 3 is a plan view from A in Figure 2, Figure 4 is a side view.
Figure 5 is a side view of the suction lever, Figure 5 is a side view of the auxiliary suction lever, Figure 6 is a perspective view of the suction port, Figure 7 is a side view of the reversing claw and the small claw base, and Figure 8 is reversing. FIG. 9 is a partially cutaway side view of the paper reversing device corresponding to FIG. 2, showing the arrangement of the claws and the suction lever, and FIG.
In the figure, a first printing unit and a second printing unit of a printing press each include a plate cylinder 1 on which a printing plate is mounted on the circumference, an inking device and a water supply device (not shown) that supply ink and water to the plate surface. A blanket cylinder 2 having the same diameter as the printing cylinder 1 and onto which the image on the printing plate is transferred is disposed below the printing cylinder 1 with its circumferential surfaces facing each other. Further, below each blanket cylinder 2, an impression cylinder 3 and an impression cylinder 4 having twice the diameter thereof are arranged with their circumferential surfaces facing each blanket cylinder 2, and both impression cylinders 3, A reversing cylinder 5 having the same diameter as the reversing cylinder 4 is provided between the reversing cylinders 4 and 4 with their circumferential surfaces facing each other. Reference numeral 6 denotes a swing device that swings using a cam mechanism, and is equipped with a swing claw that opens and closes using the cam mechanism. It is configured so as to be supplied to the first impression cylinder 3. Double diameter impression cylinders 3 and 4 rotating in the direction shown by arrow A in the figure
On the outer periphery, there is a swing device 6 that opens and closes with a cam mechanism.
swing pawl and reversing pawl device 1 on the reversing cylinder 5
A plurality of sets of gripping claw devices 9 (hereinafter referred to as claws 9) each consisting of a claw and a claw base that change the grip of a paper 8 from 4 (described later) and wrap it around the circumferential surface of the trunk by rotation of the barrel, The claw shafts are arranged in parallel at a predetermined interval on a pair of claw shafts that are mounted on equally spaced positions.

The reversing cylinder 5 rotates in the direction shown by the arrow B in the figure, and a paper reversing device that also serves as a paper gripper and is designated by the reference numeral 10 is disposed at a position that bisects its outer circumference into two equal parts in the circumferential direction. has been done. Since these two sets of paper reversing devices have exactly the same configuration, one set will be explained below. That is, the reversing drum 5 is lightweight and integrally formed by a shaft core portion, an outer peripheral portion, and a plurality of skeletons connecting these parts, and a disc-shaped bearer 11 is integrally provided at both ends. . A pawl shaft 12 is mounted between the left and right bearers 11 with its movement in the axial direction restricted, and a plurality of central portions of the pawl shaft 12 are provided with pawl bearings 13 fixed to the bottom of the notch around the body. It is pivoted by. Code 1 for the whole
4 is a plurality of sets of reversing claw devices arranged in parallel on a claw shaft 12 with different phases in the axial direction from the claws 9 on the impression cylinders 3 and 4, and is a reversing claw device shown in FIG. 7a. Claw 1
5 and a nail rest accessory 16 shown in FIG. 7b. Of these, the reversing pawl 15 includes a pawl holder 19 that is fixed to the pawl shaft 12 together with a spring receiver 17 with bolts 18, and a pawl 21 that is rotatably attached to the eccentric part of the pawl holder 19 via a pivot shaft 20. An adjustment screw 22 whose stepped portion is in contact with the upper surface of the pawl holder 19 is screwed into the pawl 21 via an L-shaped detent washer 23, and the pawl holder 19 and A claw spring 24 is mounted between the claws 21 and 24 to apply a rotational force to the claws 21 in the counterclockwise direction as shown in FIG. 7a. The nail rest accessory 16 is a nail rest holder 25 formed in a boat shape that houses the reversing claw 15.
and a claw rest 27 attached to the tip with a bolt 26 facing the claw 21, and between the other free end of the small claw rest 16 and the spring receiver 17 of the reversing claw 15. A pawl spring 28 is interposed therein which springs the pawl 21 and the pawl base 27 in a direction to close them. Furthermore, a stopper stand 30 extending over the entire length of the body is fixed to a notch 29 provided on the body circumference near the tip of the reversing claw device 14 with a bolt 31. 16 bolts 2
A stopper 32 that restricts the rotation of the reversing claw device 14 by contacting the stopper 6 is screwed into each reversing claw device 14 with a screw 34 to prevent loosening. Further, a stopper 33 against which the claw base holder 25 comes into contact when the claw is reversed is screwed into each reversing claw device 14 with the stopper 32 restricting loosening. A reversing drive shaft 35 formed in a hollow tubular shape is rotatably supported on the upstream side of the rotation direction of the reversing cylinder 5 with respect to the pawl shaft 12, and a segment gear 36 formed in a fan shape is split into this. It is tightened and fixed. The segment teeth provided on the free end side of the segment gear 36 are connected to the pinion 3 fixed to the protrusion of the pawl shaft 12.
A cam follower 38, which is in mesh with the segment gear 7 and pivotally mounted at the center of the segment gear 36, is pressed against a reversing cam 39 on the frame side by a rotational force applied to the segment gear 36 by a spring member (not shown). When the reversing cylinder 5 rotates, the segment gear 36 swings due to the action of the cam surface of the reversing cam 39 and the cam follower 38, and the entire reversing claw device 14 is brought together into the position shown in FIG. 2 and the position shown in FIG. It is configured to rotate approximately 180 degrees between the positions shown. Further, the reversing pawl device 14 is provided with a pawl opening/closing device (not shown), and is configured so that the reversing pawl 15 opens and closes at a predetermined timing during one rotation of the reversing cylinder 5.

Further, in the circumferential notch of the reversing barrel, a suction lever shaft 40 formed in a hollow tubular shape is close to and parallel to the claw shaft 12 and is pivotally supported by the left and right bearers 11, and is supported at multiple locations in the center thereof. is pivotally supported by a suction bearing 41 fixed to the bottom of the notch around the trunk, and movement in the axial direction is restricted by a collar. Reference numeral 42 denotes a plurality of suction levers arranged in parallel on the suction lever shaft 40, and as shown in FIG. On the other hand, they are arranged with different phases in the axial direction, are formed in a substantially L-shape in both side and plan views, and are fixed to the suction lever shaft 40 by bolts 43. A rubber suction head 44 integrally formed with a metal pedestal is fixed to the end surface of one free end of the suction lever 42 with a bolt 45, and the end surface of the suction head 44 is formed in an arc shape. There is. A pair of suction ports 4 are provided on the arcuate end surface and communicated with the inside of the suction lever shaft 40 through an air passage 46.
7 is open, and the air passage 46 is provided with a valve 48 for opening and closing it. The hollow suction lever shaft 40 is connected to an air source via a rotary valve (not shown), and is configured to suck outside air from a suction port 47 at a predetermined timing during one revolution of the reversing cylinder 5. Furthermore, the other free end of the suction lever 42 has a spring holder and a bolt.
A stopper 49, which is integrated with the nut and restricts the rotation of the claw base accessory 16, is biased in the projecting direction by a compression coil spring 50 and is slidably mounted.

Further, on the suction lever shaft 40, a plurality of auxiliary suction levers 51 are arranged approximately corresponding to each reversing pawl device 14 except for the one facing the suction bearing 41, as shown in FIG. The auxiliary suction lever 51 is fixed to the suction lever shaft 40 with bolts 52, and a rubber suction head 53 integrally formed with a metal pedestal is attached to the end surface of one free end of the auxiliary suction lever 51. It is fixed by a bolt 54 that is sunk. The end face of the suction head 53 is formed into an arc shape, and the width in the circumferential direction (vertical direction of the paper) is approximately 1/2 that of the suction head 44. It is configured so as not to interfere with the device 14. A suction lever shaft 40 is attached to the arcuate end surface of the suction head 53.
One suction port 56 is opened and communicated with the inside of the air passage 55 through an air passage 55, and the air passage 55 is provided with a valve 57 for opening and closing it. The suction head 53 is configured to suck outside air from a suction port 56 at the same timing as the suction head 44.

Both suction levers 42, 5 configured as above
1 is almost symmetrical in shape and arrangement left and right with respect to the center line of the machine, which is indicated by the symbol L in FIG. , 56 are opened only in approximately half of the center portion in the paper width direction.

Further, on the downstream side of the rotational direction of the reversing cylinder 5 with respect to the suction lever shaft 40, a suction drive shaft 58 formed in a hollow tubular shape is rotatably supported, and this has a segment gear 59 formed in a fan shape. is fixed and fixed. Segment teeth provided at the free end of the segment gear 59 mesh with a pinion 60 fixed to the protrusion of the suction lever shaft 40, and a cam follower 61 pivotally attached to the center of the segment gear 59 is not shown in the figure. The rotational force applied to the segment gear 59 by a spring member that does not press the suction lever rotating cam 62 on the frame side. When the reversing cylinder 5 rotates, the segment gear 59 swings due to the action of the cam surface of the suction lever rotation cam 62 and the cam follower 61, and the suction lever 4
2 and 51 are configured to rotate between the position shown in FIG. 2 and the position shown in FIG.

The double-sided printing operation of the sheet-fed rotary printing press with a reversing device configured as described above will be explained based on the above-mentioned figures and the operation explanatory diagram of FIG. 10. The reversing claw device 14 and the suction lever shaft 40, whose rotation was restricted, are now reversible and can be rotated, and the downstream cylinders including the reversing cylinder 5 and the upstream cylinders including the first impression cylinder 3 are The phase with each cylinder on the side is shifted by approximately the paper size.
In addition, the paper release timing of the cam that opens and closes the pawl 9 of the first impression cylinder 3 is delayed by approximately the same amount as the paper size. When printing is started after preparing in this way, the paper 8, which is held in the claw 9 and printed on the surface on the blanket cylinder 2 side, is held between the blanket cylinder 2 and the first impression cylinder 3.
After being released from the grip between the cylinders 2 and 3, the paper is wound around the impression cylinder 3 until the trailing edge of the paper comes into contact with the reversing cylinder 5, as shown in FIG. 10a. When the cam follower 61 of the segment gear 59 reaches the small diameter part of the suction lever rotating cam 62 a little before this, the segment gear 59 rotates against the elastic force of the spring member, and the suction lever is rotated via the pinion 60. 42 and 51 are rotated to the position shown in FIG. 9 so as to escape from the nail rest holder 25. Also, a moment later than this, the cam follower 38 of the segment gear 36 reaches the large diameter part of the reversing cam 39, the segment gear 36 rotates, and the pawl shaft 12 rotates greatly via the pinion 37, so that the entire reversing pawl device 14 is rotated. rotates to the position shown in FIG. At this time, the reversing claw 15 is closed. When the suction levers 42, 51 have finished bypassing the claw base holder 25 and no longer interfere with it, they return to the position shown in FIG. 2 again. After the above operations are instantaneously performed, when the reversing claw device 14 and the suction levers 42, 51 face the end of the paper as described above, the rotary valve opens and air is sucked from the air source, and the suction port Since the outside air is sucked through the suction heads 47 and 56, the tail of the paper 8 is suctioned to the arcuate end surfaces of the suction heads 44 and 53. From now on, while each cylinder rotates approximately 30 degrees, the suction levers 42 and 51 rotate again to the position shown in FIG. The reversing claw 15 opens and closes. In other words, the suction levers 42 and 51 that have sucked the tail of the paper rotate to the point where the reversing claw 15 is opened, bringing the tail of the paper into the gripping position, and the reversing claw 15 closes in an instant, so that the tail of the paper is reversed. It is gripped by the claw 21 of the claw 15 and the claw base 27. When holding the paper 8 by suction, the suction head 53 of the auxiliary suction lever 51 is formed with a small width in the vertical direction of the paper 8, so that the reversing claw 15
There is no interference with

At this time, the claw 9 releases the paper the moment the suction mouth suctions the end of the paper. In addition, at the same time when the reverse claw grips the paper tail, the suction levers 42 and 51
The adsorption air is cut off. As each cylinder further rotates, the reversing claw 15 rotates together with the reversing cylinder 5 while holding the tail end of the paper, and conveys the paper 8 as shown in FIG.
9, the segment gear 36 rotates due to the elastic force of the spring member, and the entire reversing claw device 14 returns to the posture shown in FIG. As a result of the paper tail being conveyed in this way, the printing surface of the paper 8 is transferred to the reversing cylinder 5.
is inverted and wound around the inversion cylinder 5 so as to be in contact with the circumferential surface of the inversion cylinder 5. Reversing claw device 14 and suction lever 42,
51 has finished rotating, it is exactly the same as in the case of single-sided printing, and after that, when the reversing claw device 14 and the claw 9 of the second impression cylinder 4 face each other, both claws 15 and 9 are turned. After opening and closing and changing the paper 8 in the mouth, the impression cylinder 4
Since the paper is wrapped around the blanket cylinder 2 and the impression cylinder 4, when it passes between the blanket cylinder 2 and the impression cylinder 4, printing is applied to the back side, resulting in double-sided printing.

In the double-sided printing operation as described above, since the auxiliary suction lever 51 is provided, the paper 8 is not only suctioned by the suction lever 42 but also has its intermediate portion and both ends suctioned by the auxiliary suction lever 51, so that the reversing claw When the paper 8 is held in the 15, the paper 8 does not droop or flap between adjacent suction levers 42 or at both ends. Furthermore, even if the edge of the paper protrudes from the suction lever 42 to the left or right depending on the paper size, the auxiliary suction lever 51 is attached to this protrusion and suctions the edge of the paper.
When the paper 8 is held in the 5's mouth, the edge of the paper does not flap. Furthermore, the suction levers 42 and 51 at both ends
By forming the suction ports 47 and 56 to be half as narrow in the width direction of the paper, it is possible to firmly support and adsorb the edge of the paper in areas where there are no suction ports 47 and 56, and the paper position in the paper width direction is slightly shifted. There is no risk of air leaking from the suction ports 47, 56. In the case of the examples, the paper size indicated by the symbol D is the minimum paper width, and the paper sizes indicated by the symbols D ₁ , D ₂ , and D ₃ are the 464-cut size, the A-half-cut size, and the chrysanthemum-half-cut size, respectively. These are paper sizes that are frequently used, but by arranging the suction levers 42 and 51 so that the portion without suction port of the suction lever 42 or 51 corresponds to the edge of these sheets, air leakage can be prevented. The edge of the paper is firmly suctioned without any fear.

In this embodiment, the suction ports 4 of the suction lever 42 and the auxiliary suction lever 51 located at both ends in the paper width direction
4 and 52 are both formed to have a small width in the paper width direction, but depending on the model and paper size, if air leakage can be prevented by simply making the suction port 52 narrow, it is not necessary to make the suction port 44 narrow. good.

[Effect of idea]

As is clear from the above explanation, according to the present invention, in the paper reversing device of a sheet-fed rotary printing press, the suction part is placed coaxially with the suction lever that causes the reversing claw to grip the paper, so as not to interfere with the reversing claw. An auxiliary suction lever formed with a small width in the vertical direction is provided in almost the same phase in the axial direction as the reversing claw, and at least some of the auxiliary suction levers located at both ends in the paper width direction and the existing suction levers By opening the air suction hole in the suction part only in approximately half of the paper width direction toward the center, when the paper is sucked by the suction lever and held in the reversing claw, the air suction hole is opened only in the middle part between adjacent existing suction levers and The protruding part of the paper edge from the existing suction lever is suctioned by the auxiliary suction lever, so the paper does not hang down from between the suction levers or flap around the edge of the paper, significantly improving registration accuracy and printing. Overlapping can be prevented and the quality of printed matter can be greatly improved. In addition, since the paper is supported by the end surface of the suction head where there are no air suction holes at the edge of the paper, the effect of preventing the paper from flapping is further enhanced, and the paper size does not change or the paper position in the paper width direction Even if there is some deviation, the air suction hole will not be opened at the edge of the paper, so there is no risk of air leakage, and the suction and gripping operations of the paper are performed reliably, improving registration accuracy.

[Brief explanation of the drawing]

1 to 10 show an embodiment of the paper reversing device for a sheet-fed rotary printing press according to the present invention, FIG. 1 is a cylinder arrangement diagram of a sheet-fed rotary printing press in which this is implemented, and FIG. A partially cutaway side view of the reversing device, FIG. 3 is a plan view from A in FIG. 2, FIG. 4 is a side view of the suction lever, FIG. 5 is a side view of the auxiliary suction lever, and FIG. 6 is the same as the suction port. Fig. 7 is a side view of the reversing claw and the small claw base, Fig. 8 is a layout diagram of the reversing claw and suction lever, and Fig. 9 shows the paper being held in the reversing claw using the suction lever. FIG. 10 is a partially cutaway side view of the paper reversing device shown corresponding to FIG. 2, and FIG. 10 is an explanatory diagram of the operation of double-sided printing. 5... Reversing cylinder, 8... Paper, 10... Paper reversing device, 12... Claw shaft, 14... Reversing claw device, 15...
...Reversing claw, 40... Suction lever shaft, 42... Suction lever, 44, 53... Suction head, 47, 56
...Suction port, 51...Auxiliary suction lever.

Claims (1)

[Scope of utility model registration request] A plurality of reversing pawls are arranged in parallel on a pawl shaft on the outer periphery of the reversing cylinder, and a plurality of reversing pawls are arranged in parallel and out of phase with the reversing pawls in the axial direction on a suction lever shaft that is close to and parallel to the pawl shaft. In a paper reversing device for a sheet-fed rotary printing press, which is equipped with a plurality of suction levers and reverses the paper by holding the end of the paper suctioned by the suction levers in a reversing claw and transporting it, the paper reversing device includes: An auxiliary suction lever having a suction port formed with a small width in the vertical direction of the paper so as not to interfere with the reversing pawl is provided in approximately the same phase in the axial direction as the reversing pawl, and a portion of the auxiliary suction lever located at both ends in the width direction of the paper is provided. A paper reversing device for a sheet-fed rotary printing press, characterized in that an air suction hole in a suction port of at least an auxiliary suction lever of the lever and the existing suction lever is opened only in approximately half of the central portion in the paper width direction.