JPH0664135A - Offset printer - Google Patents

Abstract

PURPOSE:To provide an offset printer of low height, simple structure and small size, inexpensive and easy to handle. CONSTITUTION:The effective peripheral length of an offset printer can be made long without forming the diameter of a body larger as heretofore followed and the height thereof can be lowered to a large extent and the size can be compact by constituting at least higher a plate carrier 1 or a blanket carrier 4 of an endless belt. A plurality of plates 10 can be mounted on one plate carrier 4, and a plurality of kinds of printing can be carried out continuously by one printing unit thus constituted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus, and more particularly to a simple small offset printing apparatus.

[0002]

2. Description of the Related Art Conventionally, an offset printing machine generally has a plate cylinder, a blanket cylinder, and an impression cylinder. In the case of multicolor printing,
Multicolor printing is performed by connecting the units composed of these three cylinders in tandem according to the number of colors and sequentially passing the units. The plate cylinder is composed of a cylinder having a clamp for fixing the plate on a surface thereof, and the blanket cylinder is a cylinder for winding a blanket, and a recess for accommodating the clamp is formed in an outer peripheral portion thereof like the plate cylinder. ing. Usually, the plate cylinder and the blanket cylinder have an effective perimeter longer than the length of one plate, and one plate is transferred and printed by one rotation. There is also known an offset printing machine in which the plate cylinder and blanket cylinder diameters are doubled so that the effective perimeter of 2 plates is equal to that of two plates, and printing can be performed from two types of printing plates in one rotation.

Conventionally, a large offset sheet-fed rotary printing press,
Offset printing machines of various scales are known, from an offset web-fed rotary printing machine to a small offset printing machine that prints B4 size and A4 size. Basically, the offset printing machine is effective for the plate cylinder and blanket. Since the perimeter must be longer than the plate length, there is a limit to miniaturization, and even a conventionally known small B4 size offset printing machine has a height of 20 cm or more. There is also. In addition, offset printing machines are widely used due to their quickness, simplicity, and economic efficiency compared with other plate-making type printing machines, but they are used widely, but fine adjustment of dampening water and ink and rapid attachment / detachment of three cylinders are possible. Etc., the mechanism is complicated and requires skill, and in combination with the size of the machine and its cost, it is mostly used exclusively by a printing specialist, and general printing that requires printing of multiple plates and small lots. At present, there is no small, inexpensive, and easy-to-use product that can be easily used for office work.

[0004]

As described above, in the conventional offset printing apparatus, the effective perimeter of the plate cylinder and the blanket cylinder must be equal to or longer than the length of the plate to be directly printed. When mounting, the cylinder diameter of the plate cylinder and blanket cylinder must be increased accordingly. That is, the plate length is limited by the diameters of the plate cylinder and the blanket cylinder, and the height of the printing machine is limited. Therefore, an offset printing machine having a low height cannot be obtained. Further, in the conventional offset printing machine, the unit price of the plate cylinder and the blanket cylinder is high, and the entire apparatus is expensive.
Furthermore, since the plate cylinder and the blanket cylinder are cylinders, respectively, a water supply device, an ink inking device, a cleaning device, and a drying device must be centrally provided so as to come into contact with the peripheral surface of the cylinder, resulting in a complicated structure. However, there is a problem that the operation and handling are troublesome. In particular, in the case of a small offset printing machine, since the water supply device and the ink inking device are arranged in the narrow space around the plate cylinder as described above,
It is difficult to provide even an etching device around the plate cylinder, and the etching device is usually provided separately. Therefore,
The present invention is intended to solve the problems of the above-described conventional offset printing machine, and provides an offset printing machine which is low in height, simple in structure, and small in size, inexpensive, and easy to handle. This is a technical issue.

[0005]

As a result of various studies to solve the above problems, the present inventor found that the plate cylinder and the blanket cylinder are formed by an endless belt instead of the conventional cylinder, and the present invention is realized. It has arrived. That is, the offset printing apparatus of the present invention is characterized in that at least one of the plate carrier and the blanket carrier is constituted by an endless belt, the plate carrier is an endless belt and the blanket carrier is a cylinder, Alternatively, the plate carrier is a cylinder, the blanket carrier is an endless belt, and both the plate carrier and the blanket carrier are endless belts. The endless belt,
By selecting the distance between the pulleys that rotate by suspending the endless belt, it is possible to increase the effective circumference without increasing the height. The effective circumference of the plate can be arbitrarily configured.

[0006]

By forming the plate carrier and / or the blanket carrier with an endless belt, the effective circumference can be increased without increasing the diameter of the cylinder as in the conventional case. If the distance between the axes of the pulleys is about 14 cm and the distance between the pulleys is about 5 cm, a printing machine capable of sufficiently printing B4 size paper can be obtained. In conventional cylinder type plate cylinders and blanket cylinders, in order to be able to feed B4 size paper in the longitudinal direction for printing, each cylinder diameter must be 13 cm or more, The height can be made low and compact. Moreover, since the effective peripheral lengths of the plate carrier and the blanket carrier can be freely increased, a plurality of master papers can be attached to one plate carrier, and a plurality of plates can be printed in one printing cycle.

Further, in this case, if the blanket can be overprinted and transferred, a plurality of ink inking devices are arranged in accordance with the number of plates to be attached, and each time a predetermined plate passes, the ink inking device swings to change the color. If the ink is applied, multicolor printing can be performed at the same time. Further, instead of the plate cylinder and the blanket cylinder, which are conventionally expensive to manufacture, an endless belt, which can be obtained at a relatively low cost, is used. is there.

[0008]

Embodiments of the offset printing apparatus according to the present invention will be described below in detail with reference to the drawings. The offset printing apparatus according to the present embodiment shows a case where a plate carrier and a blanket carrier corresponding to a conventional plate cylinder and a blanket cylinder are each configured by an endless belt. The plate carrier 1 is composed of an endless belt formed of a composite material having a synthetic resin as a base material,
It is hung between pulleys 2 and 3. The blanket carrier 4 on which the blanket is mounted is composed of an endless belt made of a composite material having a synthetic resin as a base material, like the plate carrier 1, and is hung between pulleys 5 and 6.
The pulley 5 is provided on a shaft 7 supported by a movable frame operated by a cylinder device or the like, and by moving the movable frame up and down, the blanket carrier is positioned on the outer peripheral portion of the pulley 2 at the outer peripheral portion of the pulley. By making the rotary contact with the plate carrier detachable and rotating them in contact with each other, the streak image of the plate attached to the plate carrier can be transferred to the blanket surface held on the blanket carrier. The plate carrier 1 and the blanket carrier 4 are forcibly rotationally driven in synchronization by the same driving means (not shown) via a transmission means.

The plate carrier 1 is provided with a gripper 11 for mounting the plate 10, and the gripper is operated by contacting a first gripper actuating cam 12 provided at a plate feeding position as shown in the drawing, and the plate is operated. The plate supplied from the supply tray 14 is sandwiched. A second gripper actuating cam 15 is attached to the plate discharge position for discharging the gripped plate to the plate discharge tray 16. Reference numeral 17 is a plate supply roller device provided on the plate supply tray, and 18 is a plate discharge roller device for discharging the plate to the plate discharge tray.

In this embodiment, an endless blanket is adopted as the blanket, and the blanket is laminated endlessly on the outer peripheral surface of the blanket carrier 4 and is integrated with the blanket carrier. The blanket carrier is provided with a metal (not shown) or an appropriate position indicator at an appropriate position, and a position detecting means 19 such as a proximity switch or a photoelectric sensor for detecting the indicator is provided at an outer fixed position of the rotation. It is provided so that the position of the blanket can be detected. However, it is of course possible to adopt a sheet-like blanket as in the conventional case and detachably attach it to the outer peripheral portion of the blanket carrier with a gripper or the like.

The impression cylinder 20 is supported by a shaft 21 supported by a movable bracket so as to rotate in pressure contact with the outer peripheral surface of the blanket carrier on the outer peripheral surface of the pulley 6 on the opposite side in contact with the plate carrier, The axial distance between the pulley 6 and the impression cylinder 20 can be arbitrarily adjusted, and the printing pressure can be finely adjusted and detached. Paper feed tray 26 for storing printing paper 25
Is provided so as to be located below the blanket carrier in the illustrated embodiment, and the printing paper 25 on the tray is provided at the upper end thereof.
A separating roller 27 is provided for separating the sheets one by one and sending them to the sheet feeding roller device 28.

As shown in the figure, the plate carrier 1 and the blanket carrier 4 are in close proximity to each other so that transfer is performed on the pulley 2 and the pulley 5 side, and a space having a triangular cross section is provided between the pulley 3 and the pulley 6 side. As they are formed, they are arranged so as to be separated from each other so as to be inclined, and an ink inking device or the like can be arranged in the space so that they can be formed compactly.
On the outer periphery of the plate carrier 1, the etching device 30 is detachably attached,
A water supply device 31 and an ink inking device 32 are sequentially provided, and a cleaning device 33 and a drying device 34 are detachably arranged on the outer peripheral portion of the blanket carrier 4 so that the cleaning device 33 and the drying device 34 can be appropriately moved to the contact position with the blanket carrier. There is. In the present embodiment, these devices are provided in one unit frame 35 so that they can be integrally attached to and detached from the main body of the printing machine in a cassette type so that they can be handled easily. You may arrange | position freely.

Next, the operation of the offset printing apparatus of the present embodiment constructed as described above will be explained. Version 10 is PS
Although a conventionally known plate such as a plate can be used, since the apparatus of this embodiment has an automatic etching device built therein, an unetched offset master paper can be used. Blanket carrier 4 before printing starts
Is located at the position shown by the broken line in the figure and is separated so as not to come into contact with the plate carrier 1. In this state, when the printing conditions such as the number of printed sheets are set in the control panel unit (not shown) and the printing machine is operated, the master paper placed on the plate feeding table is automatically transferred at an appropriate timing to the plate carrier 1. The gripper 11 is actuated by the first gripper actuating cam 12 to nip the master paper and rotate at a constant speed. First, the etching roller of the etching device is brought into contact with the master paper, and an etching process is performed to remove the image film with an etchant to expose the lipophilic layer. When the etching process is completed, the etching roller is automatically separated, and then the water supply roller of the water supply device comes into contact with the master surface, whereby water is supplied to the surface of the master paper and water adheres to the non-image area. Next, the water supply roll is separated, the ink roll of the ink deposition device comes into contact,
Ink is attached to the lines on the master paper.

When the plate carrier rotates and the ink is leveled and the preparation for printing is completed, the pulley 5 automatically swings so that the blanket carried on the blanket carrier comes into pressure contact with the master carried on the plate carrier. While rotating, the lines are transferred onto the blanket. At that time, the plate and the blanket are aligned by the blanket position detection sensor 19 detecting the reference position of the blanket, and the pulley 5 swings at a predetermined timing to bring the blanket carrier into contact with the plate carrier. . Then, at the timing and timing of the blanket, the paper is fed from the paper feed tray between the impression cylinder and the blanket carrier for printing, and the printed paper is ejected onto the ejection table (not shown). To be done. When the gripper projecting from the surface of the plate carrier passes through the contact portion with the blanket carrier, the pulley 5 swings to escape the blanket carrier from the projecting gripper.

When the printing of the predetermined number of sheets is completed, the second gripper actuating cam 15 is actuated, the gripper 11 is opened to open the master paper, and the plate is discharged from the plate carrier to the plate discharge tray 16
It is discharged upwards, the pulley 5 swings, and the pulley 5 and the pulley 2
Increase the space between and to prepare for the next printing. Next, the master on the second page is automatically supplied, and the above operation is repeated. Meanwhile, it is cleaned by a blanket cleaning device supported by the blanket carrier, and after the cleaning is completed, it is dried by a drying device to prepare for the transfer of the next image.

The preferred embodiment of the present invention has been described above, but the present invention is not limited to this embodiment, and various design changes are possible. For example, in the above embodiment, both the plate carrier and the blanket carrier were formed by endless belts, but it is not necessary to make both carriers endless belt-shaped, either one of the plate carrier or the blanket carrier is an endless belt, and the other is the same as the conventional one. Even if it has a cylindrical shape, it can be made smaller than the conventional one. In addition, the endless belt is not necessarily a single wide belt, and for example, a narrow chain or belt is provided at both ends in the carrier width direction, and an effective length sufficient to support the plate or blanket between the belts. It is also possible to fix a flexible support plate that can be bent and have the plate or blanket supported on the support plate.
Therefore, the concept of the endless belt described in the claims is not necessarily limited to only one wide endless belt, and a narrow chain or belt provided at both ends in the carrier width direction, It should be construed as including any means by which the plate can be conveyed endlessly between two pulleys.

Further, not only the mounting of the plate or blanket on the plate carrier and the blanket carrier, and the above gripper,
Any means such as vacuum can be adopted. Further, the arrangement of the plate carrier and the blanket carrier is not limited to the above embodiment, and various arrangements can be made if necessary. Further, it goes without saying that the arrangement of the ink inking device and the like can be arbitrarily selected. In particular, in this embodiment, since the endless belt is used for the plate carrier and the blanket carrier, it is not necessary to intensively provide a water supply device, an ink inking device, etc. on the cylinder peripheral surface as in the conventional case, and a flat part or the like can be arbitrarily set. It is possible to disperse and install in the position of, and the etching apparatus can also be stored compactly. The present invention can also be applied to a waterless offset printing apparatus, in which case it is not necessary to provide a water supply apparatus as in the above-described embodiment.

[0018]

The offset printing apparatus of the present invention is constructed as described above and has the following special effects. By forming the plate carrier and / or the blanket carrier with an endless belt, it is possible to increase the diameter of the barrel as in the conventional case.
The effective circumference can be increased, the height can be dramatically reduced, and the size can be reduced. Also, the ink inking device and the water supply device are not limited to the cylinder circumferential surface,
Since they can be arranged at arbitrary positions, the arrangement of these devices is easy and the structure is simple, and the etching device and the like can be stored compactly. Also, since the effective circumference of the plate carrier and the blanket carrier can be freely increased,
Multiple master papers can be attached to one plate carrier, and multiple types of printing and multicolor printing can be performed in one printing cycle. Further, instead of the conventional plate cylinder and blanket cylinder obtained by machining, an endless belt, which has a relatively low manufacturing cost, is employed, so that a low-cost printing machine can be obtained as compared with the conventional one.

[Brief description of drawings]

FIG. 1 is a schematic side view of an embodiment of an offset printing machine according to the present invention.

[Explanation of symbols]

1 plate carrier 2, 3 plate carrier pulley 4 blanket carrier 5, 6 blanket carrier pulley 10 plate 14 plate feeding tray 16 plate discharging tray 20 impression cylinder 25 printing paper 26 paper feeding tray 30 etching device 31 water supplying device 32 ink inking device 33 cleaning device 34 drying device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiro Sato 4-3, Jonai, Hanamaki-shi, Iwate Inside Shinko Seisakusho Co., Ltd. (72) Inventor Koichi Kamoi 2-15-1 Shibuya, Shibuya-ku, Tokyo Toho Seimei Building 25th floor Inside Gradco Co., Ltd. (72) Inventor Mamoru Mizuno 2-9 Nakamachi, Setagaya-ku, Tokyo

Claims (5)

[Claims] 1. An offset printing apparatus, wherein at least one of a plate carrier and a blanket carrier is composed of an endless belt. 2. The offset printing apparatus according to claim 1, wherein the plate carrier is formed of an endless belt, and the blanket carrier is formed of a cylinder. 3. The offset printing apparatus according to claim 1, wherein the plate carrier is formed of a cylinder, and the blanket carrier is formed of an endless belt. 4. The offset printing apparatus according to claim 1, wherein both the plate carrier and the blanket carrier are composed of endless belts. 5. The offset printing apparatus according to claim 1, wherein the endless belt has an effective perimeter capable of mounting a plurality of plates.