JP4301233B2 - Variable printing machine - Google Patents

Description

  The present invention relates to a variable printing machine.

  The offset type variable printing machine is configured as shown in FIG. 1, and a printing unit capable of performing a plurality of variable printings between a pair of feed rollers 1 and 2 that can perform normal rotation and reverse rotation in synchronization. 3a and 3b are arranged in the horizontal direction. Each printing unit 3a, 3b is composed of a plate cylinder 4, a blanket cylinder 5, and an impression cylinder 6. The blanket cylinder 5 has a large diameter on its peripheral surface, for example, a printing surface having a ½ circumferential length sa. A blanket 7 is attached to the peripheral surface of the large diameter portion.

  On the other hand, the plate cylinder 4 is provided with a printing plate 8 having a circumference shorter than the circumference sa of the blanket cylinder 5 at a portion in contact with the large diameter portion. The printing plate 8 of the plate cylinder 4 is supplied with ink from an inking device (not shown) provided adjacent to the plate cylinder 4. Further, a sheet buffering portion (loop portion) 9 is provided on at least one upstream side of the pair of upstream and downstream feeding rollers 1 and 2 or on the other downstream side (see, for example, Patent Document 1). .

  In this variable printing machine, printing with a circumferential length s-b whose length in the vertical direction is shorter than the circumferential length of the large-diameter portion of the blanket cylinder 5 is repeated on the continuous paper 10 continuously in the vertical direction. In this case, during the continuous rotation of the blanket cylinder 5, the continuous paper 10 travels forward at a constant speed over the circumference sa of the large-diameter portion of the blanket cylinder 5 by the action of the feed rollers 1 and 2, and during this time the above-mentioned Printing is performed with the printing circumference s-b, and then the continuous length a-s of the small-diameter portion of the blanket cylinder 5 of each printing unit 3a, 3b is opposed to the impression cylinder 6, so-called escape. 10 is traveled in the opposite direction by ab which is a non-image range, and this is repeated in order, and the sb top-and-bottom length of sb is formed on the continuous paper 10 every rotation of the blanket cylinder 5 of each printing unit 3a, 3b. Print images repeatedly without gaps Going on.

Japanese Patent Laid-Open No. 2-75561

  In this type of variable printing machine, as shown in FIG. 1, the paper threading path between the feed rollers 1 and 2 is straight, and guides are provided upstream and downstream of the printing units 3a and 3b. Does not have a roller. Therefore, when the continuous paper 10 is opposed to the small diameter portion of the blanket cylinder 5 in the return process in which the continuous paper 10 travels in the reverse direction, the continuous paper 10 in the path between the two feed rollers 1 and 2 extends over the entire length. A state in which no nip is instantaneously applied is obtained, and this is repeated for each printing.

  For this reason, in this type of conventional variable printing machine, the continuous paper on the travel path between the feed rollers 1 and 2 is likely to flutter, and in particular, slack or flutter occurs at the center of the travel path. It was easy to do, the tension was unstable, and it was easy to meander.

  For this reason, a difference in peripheral speed is provided between the upstream and downstream feed rollers 1 and 2 to increase the tension of the continuous paper 10, so that slack and fluttering due to the self-weight of the continuous paper 10 is eliminated, and meandering is suppressed. Therefore, it is necessary to prevent printing stains and scratches caused by contact with 5 and the impression cylinder 6.

  However, when a plastic film is used as the printing material, the printing material itself is vulnerable to scratches and is easily stuck to the cylinder due to static electricity. It cannot be avoided.

  In addition, if the printing material is thin, regardless of whether it is paper or film, and the travel path between the two feed rollers is more than 7m, the printing material should be tightened strongly to prevent slack and fluttering between them. As a result, a new problem due to the elongation and cutting occurs, so that the tension cannot be increased and the meandering cannot be prevented.

  The present invention has been made in view of the above, and it is an object of the present invention to provide a variable printing machine capable of smoothly performing variable printing without causing slack or fluttering even when a printing material is a plastic or a thin material. It is the purpose.

In order to achieve the above object, the variable printing machine according to the present invention continuously rotates between a pair of feed rollers that can be rotated forward and backward synchronously through a continuous printing material that is run by the feed rollers. A printing cylinder and an impression cylinder, and on the peripheral surface of the printing cylinder, at least one set of a large-diameter portion and a small-diameter portion that are printed in contact with a printing material between the impression cylinder and a circumferential direction. A printing unit is arranged, and the double feed roller travels the printing material at the same speed as the rotation speed of the large diameter portion while the large diameter portion of the printing cylinder is in contact with the printing material, and the small diameter portion is covered. In a variable printing machine in which a printing material is caused to travel in a reverse direction over a non-image area of a large diameter portion of the printing cylinder while facing the printing material, the impression cylinder of the printing unit is fed with the pair of feeds. Synchronous rotation with rollers is possible, and upstream and bottom of each impression cylinder At least one side, a guide roller for applying winding over a predetermined winding angle to the impression cylinder of the printing media as looseness or fluttering is prevented from occurring in the printing material passing between the print cylinder and the impression cylinder The guide roller is arranged to rotate synchronously at the same peripheral speed as the pressure drum.

According to the present invention, the printing material that travels between the upstream and downstream feed rollers is predetermined in each printing unit so as to prevent the printing material from being loosened or fluttered at the impression cylinder at all times. Even when the large diameter part of the blanket cylinder is detached from the impression cylinder and the nip by the blanket cylinder is not added to the printing material, the printing material can be freely moved between the two feed rollers. It becomes possible to prevent the printing material that repeats the reciprocating traveling by the variable printing from occurring, and the occurrence of slack and fluttering.

  In particular, according to the present invention, the guide roller provided on at least one of the upstream side and the downstream side of the impression cylinder of each printing unit rotates at the same peripheral speed in synchronization with the impression cylinder, so that the gap between both feed rollers is increased. The printing material that travels travels without any slippage at the winding portion with the guide roller as well as the impression cylinder.

  Therefore, it is possible to make it difficult to cause scratches and print stains due to rubbing on the impression cylinder and the guide roller when a plastic film is used as the printing material.

  In addition, since it is not necessary to apply a large tension to remove slack and flutter, variable printing can be performed without stretching or cutting even if a thin material is used for the printing material, and tension can be applied with thin paper. In the case where there is no film printing, a great effect can be exhibited.

  An example of the variable printing machine according to the present invention will be described with reference to FIGS. The same components as those of the conventional configuration shown in FIG.

  A plurality of (four) variable prints made up of a plate cylinder 4, a blanket cylinder 5 and an impression cylinder 6 in the traveling path between the upstream and downstream feed rollers 1, 2 in the traveling direction of the continuous paper 10. Printing units 3a, 3b, 3c and 3d are arranged. The plate cylinder 4 and the blanket cylinder 5 of each of the printing units 3a to 3d are rotated in the running direction of the continuous paper 10 at the same peripheral speed. Although not shown in FIG. 2, a printing plate is mounted on the plate cylinder 4 and a blanket is mounted on the blanket cylinder 5 on the peripheral surface of each large diameter portion. Note that sheet buffering portions 9a and 9b are disposed on the upstream side of the upstream feed roller 1 and on the downstream side of the downstream feed roller 2, respectively. In the figure, reference numeral 11 denotes a paper feeding unit arranged on the upstream side of the upstream paper buffer 9a.

Upstream and downstream of each of the impression cylinder 6 in each printing unit 3 a to 3 d, the continuous paper 10 passing between the blanket cylinder 5 and impression cylinder 6 of each unit 3 a to 3 d to the impression cylinder 6, the continuous paper Guide rollers 12 a and 12 b for winding over a predetermined winding angle are disposed so as to prevent the slack and flutter from occurring in 10 .

  The guide rollers 12a and 12b are connected to the impression cylinder 6 of the printing units 3a to 3d, and are synchronously rotated at the same peripheral speed as the impression cylinder 6.

FIG. 3 shows a drive system for the guide rollers 12a and 12b. In the figure, one guide roller 12a is connected to the drive shaft of the impression cylinder 6 through a gear train 13, and the other guide roller 12b is connected to the one guide roller 12a by a belt 14, Both guide rollers 12a and 12b are synchronized with the rotation of the impression cylinder 6 and rotated at the same peripheral speed.

  In addition, a UV dryer 15 is provided between the impression cylinder 6 and the downstream guide roller 12b so as to dry the printing portion of the continuous paper 10 so as to face the continuous paper 10 passing there between.

  At least one guide roller 12b of the guide rollers 12a and 12b provided on the upstream and downstream sides of the impression cylinder 6 is movable in the direction of changing the length of the paper path between the printing units 3a to 3d. The position movement at this time prevents the connecting system span of the guide rollers 12a and 12b from changing.

  Further, the plate cylinder 4 and the blanket cylinder 5 of each printing unit 3a to 3d are connected to one drive source via a driving shaft or the like, or can be rotated synchronously by connecting a single motor which can be controlled to rotate. It has become. Similarly, the upstream and downstream feed rollers 1 and 2 and the impression cylinders of the printing units 3a to 3d are connected to one drive source via a driving shaft or the like, or individually controlled to be controlled in rotation. Can be rotated in synchronism with the same peripheral speed.

In the above configuration, the continuous paper 10 between the feed rollers 1 and 2 is passed between the blanket cylinder 5 and the impression cylinder 6 of each of the printing units 3a to 3d. At this time, the continuous paper 10 is predetermined so as to prevent the continuous paper 10 from being loosened or fluttered in the pressure drum 6 via the guide rollers 12a and 12b on the upstream side and the downstream side of each pressure drum 6. It is wound at the winding angle.

  Accordingly, the feed rollers 1 and 2 and the pressure drum 6 of each of the printing units 3a to 3d are rotated forward and backward in conjunction with the operation of each of the printing units 3a to 3d. That is, while the continuous paper 10 is run in the normal rotation direction over the circumference of the large diameter portion of the blanket cylinder 5 of each printing unit 3a to 3d, while the small diameter portion of the blanket cylinder 5 faces the impression cylinder 6, Only the non-image range, which is an extra travel distance in the forward direction, is fed back.

At this time, the impression cylinder 6 and the guide rollers 12a and 12b are rotationally controlled at the same peripheral speed in synchronization with the running direction and running speed of the continuous paper 10, and the continuous paper 10 is slackened into the impression cylinder 6 and the continuous paper 10. In order to prevent the occurrence of fluttering and fluttering, the vehicle is guided and traveled in the forward and reverse directions without being slackened or fluttered in a state of being wound at a predetermined winding angle.

  Thus, even when the small diameter portion of the blanket cylinder 5 of each printing unit 3a to 3d is opposed to the impression cylinder 6 and the nip by the blanket cylinder 5 is not acting, the continuous paper 10 is printed on each printing unit 3a to 3d. In this way, the paper is run while being wound around the impression cylinder 6, and the slack and fluttering of the continuous paper that runs backward in a state where the nip does not act on the small diameter portion of the blanket cylinder 5 are prevented. .

  At this time, before and after each of the printing units 3 a to 3 d, the guide rollers 12 a and 12 b that guide the continuous paper 10 are rotated at the same peripheral speed in synchronization with the impression cylinder 6, so that the continuous passes therethrough. The paper 10 travels without slipping with respect to the guide rollers 12a and 12b.

  At this time, since the continuous paper 10 that has passed through the impression cylinder 6 in the forward rotation direction is opposed to the UV dryer 15, the printing unit printed by each of the printing units 3 a to 3 d is immediately used by the UV dryer 15. Since the printing section is dried, the printing section is not contaminated by the guide rollers 12a and 12b provided on the upstream side and the downstream side in the vicinity of the impression cylinder 6.

  In the above variable printing operation, when the printing length in each of the printing units 3a to 3d is changed, the adjustment of the paper path between the printing units at this time moves the position of the guide roller 12b that can be moved. Is done. Note that the paper path adjustment at this time may be performed by moving the printing unit and changing the unit interval as in the conventional case. In this case, the guide roller 12b does not need to move and may be fixed.

  In addition, although the printing units 3a to 3d in the above embodiment have been described as the offset type, it is needless to say that the printing units 3a to 3d may be a direct printing type that does not use a blanket cylinder.

In the above configuration, the guide rollers 12 a and 12 b are not necessarily used on both the upstream side and the downstream side of the impression cylinder 6, and the main point is to prevent the continuous paper 10 from being loosened or fluttered in the impression cylinder 6. As long as it can be wound, it may be provided on either one.

  Further, the UV dryer 15 provided on the downstream side of the impression cylinder 6 is not limited to this, and other dryers may be used as long as the drying power is strong.

It is a schematic configuration explanatory view showing a conventional variable printing machine. 1 is a schematic configuration explanatory view showing a variable printing machine according to the present invention. It is explanatory drawing which shows an example of the drive system of a guide roller roughly.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 2 ... Feed roller, 3a, 3b, 3c, 3d ... Printing unit, 4 ... Plate cylinder, 5 blanket cylinder, 6 ... Impression cylinder, 7 ... Blanket, 8 ... Printing plate, 9, 9a, 9b ... Paper buffer part DESCRIPTION OF SYMBOLS 10 ... Continuous paper, 11 ... Paper feed part, 12a, 12b ... Guide roller, 13 ... Gear train, 14 belt, 15 ... UV dryer.

Claims (1)

Between a pair of feed rollers that are capable of forward and reverse rotation synchronously, a printing cylinder and an impression cylinder that continuously rotate through a continuous printing material that is run by the feed roller. At least one set of printing units in which a large-diameter portion that performs printing in contact with a printing material between the cylinder and a small-diameter portion is provided in the circumferential direction, and the double-feed roller has a large diameter of the printing cylinder The printing material travels at the same speed as the rotation speed of the large diameter portion while the portion is in contact with the printing material, and the large diameter portion of the printing cylinder is in contact with the small diameter portion facing the printing material. In a variable printing machine that runs the printing material in the reverse direction over the non-image area,
The impression cylinder of the printing unit can be rotated synchronously with the pair of feed rollers, and at least one of the upstream side and the downstream side of each impression cylinder is slack or fluttered in the printing material passing between the printing cylinder and the impression cylinder. In order to prevent the occurrence of occurrence, a guide roller is provided for winding the printing material around the pressure drum over a predetermined winding angle,
A variable printing machine characterized in that the guide roller is rotated synchronously at the same peripheral speed as the impression cylinder.

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