CN102991110B - Mechanical platform of digital ink-jet printer of single sheet - Google Patents

Abstract

A mechanical platform for a sheet-fed digital inkjet printing machine belongs to the technical field of printing machinery. Its structure mainly includes four parts: machine base, paper supply unit, printing transfer unit, and paper delivery unit. The printing transfer unit is composed of a quadruple-diameter transfer cylinder, two double-diameter impression cylinders, a double-diameter transfer cylinder, a double-diameter reversing cylinder and a single-diameter reversing cylinder. The double-diameter transfer roller is located under the inkjet head. The first double-diameter impression roller, double-diameter paper transfer roller, double-diameter reversing roller, single-diameter reversing roller, and the second double-diameter impression roller appear in sequence. The V-shape is arranged under the quadruple-diameter transfer drum. The platform forms a transfer unit through the arrangement of a transfer cylinder, two variable-diameter impression cylinders and other related cylinders, which can realize the conversion of single-sided and double-sided printing, and the transfer printing accuracy is high.

Description

Sheet-fed digital inkjet printing machine mechanical platform

technical field

The invention relates to a mechanical platform for a high-speed (>10000 r/h), sheet-fed (double-sided printing) digital inkjet printing machine, which belongs to the technical field of printing machinery.

Background technique

With the rapid development of social informatization and networking, digital inkjet printing technology will gradually replace traditional offset printing technology. In the past few years, magnetic powder and electronic ink digital printing technologies have been relatively mature. Digital copiers (Kodak, Fuji, Canon, etc.) and electronic ink digital printing machines (HP) have spread rapidly, and small-format (below 52 specifications) offset printing machines have been greatly impacted. At the same time, digital inkjet printing technology has also made great progress with the improvement of inkjet head technology. Web digital inkjet printing machines of various specifications have been marketed one after another. The resolution can reach 1200dpi×1200dpi, and the speed can reach 200 m/min. , basically meet the needs of mass color printing. Some experts have done economic analysis on the printing method and printing volume. Magnetic powder and electronic ink digital printing machines are suitable for small batch (short-run) printing. The machine is suitable for large-volume (long-run) printing, the minimum economic limit is 10,000 sheets, and the profit margin will drop rapidly if it is less than the limit. Between the two economic limits of 1,000 to 10,000 sheets is the effective profit margin of sheet-fed digital inkjet printing machines. For several years, everyone has been trying to develop sheet-fed digital inkjet printing machines. So far, only Israel The company made a breakthrough and highlighted three (S5, S7, S10) sheet-fed digital inkjet printing machines at drupa in May 2012, with a maximum printing speed of 11,000 r/h, which caused a huge sensation, although its The technology still needs to be perfected, but it is enough to show that digital printing technology may replace traditional offset printing technology in the near future.

The structure of Landa's sheet-fed digital inkjet printing machine is mainly divided into four parts: control system, inkjet system, transfer belt, transfer platform, see attached drawing 5. In the accompanying drawings: 11 is the inkjet system, 12 is the transfer belt, 13 is the pressure roller, 14~19 is the cylinder part of the transfer platform, and 20 is the delivery mechanism. The inkjet system sprays the ink on the designated position on the surface of the transfer belt. During the rotation of the transfer belt, the pressure roller 13 and the impression rollers 15 and 19 are separated to complete the transfer. Under the contact pressure, 100% of the ink is transferred to the paper surface. . The transfer printing platform adopts the mechanical structure of traditional two-color offset printing machine for paper feeding, paper transfer, and paper delivery. When printing on one side, the transfer belt is only clutched with the impression roller 15 times (the roller surface is closed, the roller mouth is separated, and the impression roller is rotated once for two clutches). times); during double-sided printing, the transfer belt is clutched with the impression rollers 15 and 19 in a prescribed order (the roller surfaces are closed, the roller mouths are separated, and the impression rollers are rotated once a week), and the double-sided printing is realized by turning the roller 18. Since the lateral position of the transfer belt will deviate when it is running at high speed, especially during high-speed printing, the alternating clutch pressure of the transfer belt and the impression roller will fluctuate, which will cause the accuracy of the transfer position of the ink screen to be low, and it is difficult to achieve color printing. requirements, it is difficult to commercialize.

Contents of the invention

In order to solve the above existing technical problems, the present invention provides a mechanical platform of a sheet-fed digital inkjet printing machine. The mechanical platform of the inkjet printing machine does not use a transfer belt, but uses a roller transfer method to realize the transfer function, and the transfer accuracy is high.

The invention is realized through the following technical solutions: the mechanical platform of the sheet-fed digital inkjet printing machine is mainly composed of four parts: a machine base, a paper supply unit, a printing transfer unit, and a paper delivery unit; it is characterized in that: The printing transfer unit is composed of a quadruple-diameter transfer cylinder, two double-diameter impression cylinders, a double-diameter transfer cylinder, a double-diameter reversing cylinder and a single-diameter reversing cylinder. The double-diameter transfer cylinder and two double-diameter impression cylinders are arranged in a star shape, the first double-diameter impression cylinder, double-diameter paper transfer cylinder, double-diameter reversing cylinder, single-diameter reversing cylinder, Double-diameter impression cylinders are arranged sequentially in a V shape under the quadruple-diameter transfer cylinder.

With the axis of the quadruple-diameter transfer cylinder as the vertex, the angle α between the axis of the quadruple-diameter transfer cylinder and the axis of the two adjacent double-diameter impression cylinders ranges from 110° to 140° Take the axis of the first double-diameter impression cylinder as the vertex, the axis of the first double-diameter impression cylinder and the adjacent four-diameter transfer cylinder and the axis of the double-diameter paper transfer cylinder are connected. The line angle β ranges from 70° to 90°; with the axis of the second double-diameter impression cylinder as the apex, the axis of the second double-diameter impression cylinder and the adjacent quadruple-diameter transfer cylinder , The range of the angle γ between the axes of the single-diameter reversing drum is between 70° and 90°.

A backing plate is installed on the embossing cylinder.

The thickness of the backing plate is 0.5~1.5mm.

Beneficial effects of the present invention: the present invention adopts the above-mentioned structure, through the arrangement and combination of the transfer cylinder, two embossing cylinders and other related cylinders, without using the transfer belt, and adopting the cylinder transfer method to realize the transfer printing function, the transfer printing accuracy High, can achieve printing position error of less than 0.1 mm, if the inkjet head equipped with an inkjet system has an inkjet speed of 150m/min, and can achieve 100% ink transfer, it can be commercialized. A 0.5~1.5mm backing plate is installed on the impression cylinder to realize the conversion of single-sided and double-sided printing.

Description of drawings

Figure 1 is a schematic diagram of the mechanical platform of a sheet-fed digital inkjet printing machine.

Fig. 2 is a schematic diagram of the arrangement angle structure between the cylinders of the printing transfer unit.

Fig. 3 is a schematic diagram of the clutch pressure and pressure regulating structure of the transfer roller.

Fig. 4 is a schematic diagram of the variable diameter structure of the embossing roller.

Figure 5 is a schematic diagram of the structure of Landa sheet-fed digital inkjet printing machine.

Detailed ways

The mechanical platform of a sheet-fed digital inkjet printing machine is equipped with a paper supply unit, a paper delivery unit and a printing transfer unit in the machine base, wherein the paper supply unit and the paper delivery unit are the same as the prior art.

This embodiment will describe in detail the design point of this application—the printing transfer unit. As shown in Figure 1, the printing transfer unit is composed of a quadruple diameter transfer cylinder 2, two double diameter impression cylinders 4, 8. A double-diameter paper transfer cylinder 5, a double-diameter overturning cylinder 6 and a single-diameter overturning cylinder 7 are formed. The first embossing cylinder 4 is connected to the paper supply unit through the delivery cylinder 3, and the second embossing cylinder 8 is connected to the paper delivery unit through the delivery sprocket 9, and each cylinder is driven by high-precision gears to ensure transmission accuracy. The quadruple-diameter transfer cylinder 2 is located below the inkjet head 1, the first double-diameter impression cylinder 4, the double-diameter transfer cylinder 5, the double-diameter turning cylinder 6, the single-diameter turning cylinder 7, the second double-diameter Double-diameter impression cylinders 8 are arranged in a V-shape below the quadruple-diameter transfer cylinder 2 in sequence.

The specific arrangement angles of the above-mentioned cylinders are shown in Figure 2: with the axis of the quadruple-diameter transfer cylinder 2 as the apex, the axis of the quadruple-diameter transfer cylinder 2 and the adjacent first double-diameter impression cylinder 4. The angle α between the axes of the second double-diameter impression cylinder 8 ranges from 110° to 140°; with the axis center of the first double-diameter impression cylinder 4 as the apex, the first double-diameter The shaft center of the impression cylinder 4 and its adjacent quadruple-diameter transfer cylinder 2 and the shaft center of the double-diameter paper transfer cylinder 5 have an included angle β range between 70° and 90°; The axis center of the double-diameter impression cylinder 8 is the apex, and the axis center of the second double-diameter impression cylinder 8 and its adjacent quadruple-diameter transfer cylinder 2 and single-diameter reversing cylinder 7 include an angle γ range Between 70°~90°.

The clutch pressure of the quadruple-diameter transfer cylinder 2 is pneumatically controlled by the working cylinder 24, and the pressure adjustment of thin and thick paper is controlled by the manual pressure regulating screw 21. The principle is shown in Figure 3. The bearing sleeve of the quadruple-diameter transfer cylinder 2 is an inner eccentric sleeve 27 1. The combined structure of the outer eccentric shaft sleeve 23 realizes clutch pressure and pressure adjustment between the first double-diameter impression cylinder 4 and the second double-diameter impression cylinder 8 by rotating the eccentric bearing. The cylinder 24 drives the inner eccentric sleeve 27 to rotate to realize the clutch pressure operation, and the manual pressure regulating screw rod 21 drives the outer eccentric sleeve 23 to rotate to realize the pressure regulation operation.

As shown in Figure 4, taking the first double-diameter impression cylinder 4 as an example, a backing plate 41 with a thickness of 0.5-1.5 mm is installed on the outer surface of the first double-diameter impression cylinder 4 to make its diameter Reach the working size and meet the printing requirements.

The working principle of printing transfer printing is as follows:

1. When printing on one side: the first double impression cylinder 4 is equipped with a backing plate 41 on both working surfaces, and the size of the working surface is the theoretical value; the second double impression cylinder 8 is not equipped with a backing plate, and the two working surfaces The diameter is smaller than the theoretical size, and the impression cylinder rotates once to supply two sheets of paper, and the four working surfaces of the transfer cylinder are sequentially transferred to the same side of the paper.

2. For double-sided printing: add backing plates to the corresponding working surfaces of the first and second double-diameter impression cylinders 4 and 8. The diameter is the theoretical value, and the diameter of the other working surface is smaller than the theoretical size. The impression cylinder rotates once to supply a sheet of paper, and the paper is turned over by the single-diameter reversing cylinder. The paper is just handed over to the working surface of the impression cylinder with a backing plate. There is a gap between the paper-free surface of the impression cylinder and the transfer cylinder. The front side is transferred on the first double-diameter impression roller, and the reverse side of the paper is transferred on the second double-diameter impression roller. The four working surfaces of the transfer roller are transferred to the same impression roller at intervals.

Claims (6)

1. The mechanical platform of a sheet-fed digital inkjet printing machine, including a machine base, a paper supply unit, a printing transfer unit, and a delivery unit; it is characterized in that: the printing transfer unit is composed of a four-fold diameter transfer cylinder , two double-diameter impression cylinders, a double-diameter paper transfer cylinder, a double-diameter turning cylinder and a single-diameter turning cylinder; the quadruple-diameter transfer cylinder and two double-diameter embossing The rollers are arranged in a star shape, the first double-diameter impression cylinder, double-diameter paper transfer cylinder, double-diameter reversing roller, single-diameter reversing roller, and the second double-diameter impression roller are arranged in a V shape in sequence. Below the quadruple diameter transfer roller. 2. The mechanical platform of the sheet-fed digital inkjet printing machine according to claim 1, characterized in that: the axis of the quadruple-diameter transfer cylinder is the apex, and the axis of the quadruple-diameter transfer cylinder is connected to the two double The angle α between the axis lines of the first double-diameter impression cylinders ranges from 110° to 140°; with the axis center of the first double-diameter impression cylinder as the apex, the axis of the first double-diameter impression cylinder and the four The angle β between the shaft centers of the double-diameter transfer cylinder and the double-diameter paper transfer cylinder ranges from 70° to 90°; with the axis of the second double-diameter impression cylinder as the apex, the second double-diameter The angle γ between the axis of the embossing cylinder and the axis of the quadruple-diameter transfer cylinder and the single-diameter reversing cylinder is in the range of 70° to 90°. 3. The mechanical platform of a sheet-fed digital inkjet printing machine according to claim 1 or 2, wherein a backing plate is installed on the first double-diameter impression cylinder. 4. The mechanical platform of a sheet-fed digital inkjet printing machine according to claim 1 or 2, wherein a backing plate is installed on the second double-diameter impression cylinder. 5. The mechanical platform of a sheet-fed digital inkjet printing machine according to claim 3, wherein the thickness of the backing plate is 0.5-1.5mm. 6. The mechanical platform of a sheet-fed digital inkjet printing machine according to claim 4, wherein the thickness of the backing plate is 0.5-1.5 mm.