KR100879240B1 - Digital printing machine having hot air flow type ink dryer - Google Patents

Abstract

The present invention relates to a digital printing machine, comprising a case in which a tapered-shaped flow guide tube is formed therein, a heater formed in a coil spring shape having a gradually decreasing diameter, and disposed below the flow guide tube, and a flow guide tube. A pair of air heater assemblies coupled to an upper part of the case and a blower fan coupled to an upper portion of the case to generate forced flow in the flow guide tube, respectively mounted on left and right sides of the printing head; And a head movement sensor for detecting a moving direction of the printing head, and comparing the temperature value detected by the temperature sensor with a set temperature to adjust the amount of heat generated by each heater, and printing in accordance with the information detected by the head movement sensor. By providing a digital printing machine having a hot-air ink drying apparatus comprising a; air heater controller including a microcomputer to selectively turn on / off the power so that only one air heater assembly mounted on the opposite side of the head moving direction; Regardless of the type of media, the ink sprayed by the hot-air ink drying apparatus can be quickly dried or cured even without a separate structure having a large space and cost burden.

Printing head, flow guide tube, air heater assembly, heater, hot wire receiving tube, blowing fan

Description

Digital printing machine with hot air ink drying machine {DIGITAL PRINTING MACHINE HAVING HOT AIR FLOW TYPE INK DRYER}

1 is a perspective view showing an example of a digital printing machine according to the prior art,

Figure 2 is a perspective view of a digital printing machine having a hot air ink drying apparatus according to the present invention,

3 is an enlarged perspective view of a portion A of FIG. 2;

4 is an exploded perspective view of an air heater assembly according to the present invention;

5 is a cross-sectional view schematically showing the assembled state of the air heater assembly of FIG.

6 is a detailed structural diagram showing a heater according to the present invention;

Figure 7 is a rear view showing a mounting structure of the air heater assembly according to an embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

100: printing head 103: flow guide tube

105: case 107: temperature sensor

110, 110: air heater assembly 113: heating wire

115: heater 116: heating wire receiving tube

117: hot wire protection member 119: adjustment screw

125: blower fan 127: mounting bracket

133: mounting bracket

The present invention relates to a digital printing machine, and more particularly, to provide a hot air ink drying apparatus for achieving high quality of printing and improvement of quality by rapidly drying or curing ink sprayed from a printing head to media. It relates to a digital printing machine.

In general, a digital printing machine is a machine that prints on a principle similar to an inkjet printer widely used for offices, and uses various colors of ink according to an output signal for a character or an image to be digitized through a digital controller. It is a device that performs printing by spraying onto a media through a printing head. However, unlike general inkjet printers, digital printing machines are commercially used to produce large-scale prints such as banners, and although paper media such as natural pulp can be used as media, such as cloth, plastic film, leather, etc. Special materials can be used as media.

The digital printing machine uses a subtractive blending technique that frequently injects three primary colors of yellow, cyan, and black into media to produce various colors, thereby providing a printed image of a desired image. Of course, the above three primary colors as well as other color inks such as soft sake, light blue green, etc. may be additionally used to enable more diverse and sophisticated color expression.

Printing using such a subtractive mixing technique supplies ink with different colors to the printing head, and the ink ejected from the head is overlaid on the media to realize a new color.

1 is a perspective view showing an example of a digital printing machine according to the prior art.

Digital printing machine according to the prior art, as shown in Figure 1, a plate-shaped base (1) formed long left and right, and a pair of left and right supports for supporting the base 1 in a structure supporting from both sides (3) is formed as a basic skeleton. The base 5 is provided with a transfer table 5 which is formed to be left and right to be parallel to the base 1 with a predetermined gap on the base 1, and can be reciprocated from side to side in a state constrained by the transfer table 5. And a printing head 7 formed with a plurality of nozzles (not shown) for ejecting ink into the media. In addition, the printing head 7 consists of a configuration including a conveying means including a conveying belt 20 and a conveying motor 11 for providing a driving force to reciprocate left and right on the conveying table (5).

On the other hand, there is provided a rear input side roller (not shown) for supplying the media to be used in the printing operation (in the direction of the arrow in FIG. 1), and an output side roller 12 for recovering the media after being printed again. Can be.

Such a digital printing machine is confined to the conveyer 5 while conveying the media at a constant speed so as to pass into the space between the base 1 and the conveyer 5 having a predetermined vertical space and left and right widths. The printing operation is performed in such a manner that a desired character or image is printed on the media through ink jetting by the printing head 7 reciprocating from side to side. More specifically, the conveyance of the media is realized by driving the input side roller and the output side roller 12 directly through driving means (not shown). It can be realized by a pair of feed rollers (not shown) mounted in the inner space between the feed table 5 and the base 1, and the feed speed of the media can be linked with the printing speed by the printing head 7. Controlled. That is, the media is placed on the base 1 and placed under the printing head 7 in the process of being transported, for example, from the back (for the direction of the arrow in FIG. 1) by the driving means or the like at the set printing speed. The ink is ejected from the nozzles (not shown) of the printing head 7 to the portion to perform a printing operation.

In such a digital printing apparatus, in order to improve the print quality at the same time while improving the printing speed required in terms of productivity, it is necessary to dry or harden quickly after the liquid ink is injected as its precondition.

For example, a case in which the media printed as described above is directly wound on the output side roller 12 is described. If the sprayed ink is not quickly dried or cured, it is overlapped in the process of winding on the output side roller 12. As the ink may adhere to the paper surface and may also spread around the spot where the ink is ejected, it is difficult to obtain the print quality as expected. To ensure print quality, ink does not bleed or spread to the surroundings, and to achieve this, sufficient time necessary for dry curing of the ink must be secured. One of the things that can be considered to ensure sufficient time for drying or curing is to slow down the printing speed. However, this would never be desirable in terms of productivity.

On the other hand, without being accompanied by a decrease in printing speed, what can be considered to ensure sufficient time for drying or curing, the drying workbench extending by a considerable distance in the direction of the media to the output side of the digital printing apparatus There is a way to install a separate structure such as, and to install the output side roller in the front end of the structure. In such a case, while the printing speed is maintained at least, the feeding distance from the position where the ink is ejected to the output side roller is increased to secure the time required for drying or curing the ink. It causes a problem that increases significantly.

In order to solve the above problems, various techniques have been disclosed for shortening the time required for drying or curing to enable high-speed printing while realizing a high level of print quality.

As an example, a method of supplying air toward the printed portion to promote drying or curing of the ink may be considered. However, if the supplied wind is not finely controlled, a drop in spraying from the nozzle of the printing head may be considered. It may not be appropriate because there is a problem that the ink may be affected by the wind and may not fall accurately to the predetermined position, and the nozzle may be clogged while the ink is solidified by the wind around the nozzle.

As another example, a heat wire and a thin heat generating means are built in the base so as to heat the surface of the base 1 so that heat is directly transferred to the medium in the course of passing the medium over the heated base 1. Digital printing machines have been provided that allow the ink to dry or cure faster. However, this is a suitable aspect when using the paper as a media, but it can be said that there is a limit that can not be used when using a media of a material such as cloth or plastic film vulnerable to deformation by heat.

On the other hand, in order to solve the problems of the prior art as described above, special inks such as UV (ultraviolet) reactive ink, thermal reactive ink, etc., which are preferable for rapid drying or curing, have been developed.

UV-reactive ink is an ink that has a property of curing when irradiated with ultraviolet rays, and cures rapidly upon receiving ultraviolet rays. However, together with digital printing machines, a device capable of irradiating ultraviolet rays is required. In other words, it is necessary to arrange a special structure including the ultraviolet irradiation device on the output side of the digital printing machine. This results in a problem of a considerable burden in terms of space as well as cost.

A thermally reactive ink is an ink that is designed to have a property of curing under heat, and is cured quickly by supplying heat. However, as with UV reactive inks, there is a need for a device for supplying heat with a digital printing machine. That is, a special structure including an infrared irradiation device, a heater, or a drying device combining a heater and a blower needs to be disposed on the output side of the digital printing machine. This, too, results in a problem that results in considerable burden in terms of space as well as cost.

As invented to solve the problems of the prior art as described above,

The present invention can be used irrespective of the type of ink used and the type of media, and while minimizing the space and cost burden, it is possible to locally provide a finely controlled hot air to the media to provide ink sprayed onto the media. It is an object of the present invention to provide a digital printing machine having a hot air ink drying apparatus that can be quickly dried or cured.

The present invention for achieving the above object,

A plate-shaped base that is formed to be long left and right, a pair of left and right supports that support the base in a structure supporting from both sides, and a transfer table formed to be long to the left and right to be arranged side by side with a predetermined gap on the base; A printing head which is mounted to reciprocate from side to side in the state of being restrained by the carriage and has a plurality of nozzles for injecting ink into the media below, and the reciprocating movement of the printing head from side to side on the carriage. In the digital printing machine including a conveying means for providing a driving force,

The flow guide tube is formed in a case in which a tapered flow guide tube having a gradually decreasing diameter from top to bottom is formed therein, and a coil spring shape gradually decreasing in diameter from top to bottom so as to correspond to a lower shape of the flow guide tube. The heater is disposed in the lower portion of the inside, the temperature sensor is disposed in the center of the flow guide tube, and a blower fan coupled to the upper case to generate a forced flow in the flow guide tube, each of the left and right sides of the printing head A pair of air heater assemblies mounted to position; And

Head movement detection sensor for detecting the movement direction of the printing head, and comparing the temperature value detected by the temperature sensor and the set temperature to adjust the amount of heat generated by each heater, according to the information detected by the head movement sensor And an air heater controller including a microcomputer for selectively turning on / off the pair of air heater assemblies such that power is connected only to the one air heater assembly mounted on the opposite side of the printing head in the printing direction of printing. Provided is a digital printing machine having a hot air ink drying device.

And, the heater is formed in a coil spring shape of a heating wire that generates heat when the power is connected, and the shape of the diameter gradually decreases from the top to the bottom, the inside, so that the heating wire can be built in, the inlet side and the outlet side It is characterized in that it comprises a hot wire protection member having a hot wire receiving tube which is formed to be connected to each other at the lower end portion side by side in parallel with each other in a state separated from each other from the upper end is formed an opening.

The hot wire accommodating tube may be sealed in a vacuum state in which the hot wire is embedded.

Hereinafter, exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

Figure 2 is a perspective view of a digital printing machine having a hot air ink drying apparatus according to the present invention, Figure 3 is an enlarged perspective view of a portion A of FIG.

Digital printing machine having a hot air ink drying apparatus according to the present invention, as shown in Figures 2 and 3, a pair of air heater assembly (110, 110) respectively mounted on the left and right sides of the printing head 100 And an air heater controller (not shown) for controlling the pair of air heater assemblies 110 and 110 '. The pair of air heater assemblies 110 and 110 ′ are mounted to the printing head 100 reciprocating from side to side on the conveying table 5 for ink ejection during a printing operation, so that the reciprocating motion of the printing head 100 is performed. Will move together. However, it is preferable that the air heater controller is not mounted to the printing head 100, and the air heater controller may be installed at any position on the digital printing machine as long as it can be electrically connected to the air heater assemblies 110 and 110 '. will be.

Figure 4 is an exploded perspective view of the air heater assembly according to the present invention, Figure 5 is a cross-sectional view schematically showing the assembled state of the air heater assembly of Figure 4, Figure 6 is a detailed structural diagram showing a heater according to the present invention, 7 is a rear view showing a mounting structure of the air heater assembly according to an embodiment of the present invention.

Air heater assembly 110, 110 'constituting the hot air ink drying apparatus according to the present invention, as shown in Figure 4 and 5, tapered flow guide tube of gradually decreasing diameter from top to bottom The lower part of the flow guide tube 103 is formed in a case 105 having an inside formed therein and a coil spring shape gradually decreasing in diameter from top to bottom to correspond to the lower shape of the flow guide tube 103. A blower coupled to the heater 115 disposed at the center, the temperature sensor 107 disposed at the center of the flow guide tube 103, and the upper portion of the case 105 to generate a forced flow downward in the flow guide tube 103. It consists of a configuration including a fan (125).

Specifically, the heater 115, as shown in Figure 6, is formed in a coil spring shape of the heating wire 113 that generates heat when the power is connected, and the diameter gradually decreases from top to bottom, therein , A heating wire protection member 117 having a heating wire receiving tube 116 to allow the heating wire 113 to be embedded therein. The hot wire receiving tube 116 formed therein in the hot wire protection member 117 may be divided into an inflow side and an outflow side, and each opening is formed at an upper end, and extends to the vicinity of the lower end side by side in isolation from each other. Both sides are formed to be connected to each other at the lower end and are formed in the form of one connected passage, thereby preventing a short circuit or an accident such as electric shock from occurring in the heating wire 113 accommodated therein. In addition, the hot wire accommodating tube 116 is sealed in a vacuum state with the hot wire 113 embedded therein. As the heating wire 113 is located inside the heating wire receiving tube 116 sealed in a vacuum state, the heating wire 113 is exposed to the atmosphere and oxidizes with the passage of time. This is significantly reduced.

The heater 115 is constrained to be positioned below the flow guide tube 103 by a fixing means, and the fixing means restrains the heater 115 and at the same time detects a temperature inside the flow guide tube 103. It serves to fix the temperature sensor 107 of the shape. In more detail, as an example, the fixing means may be composed of three adjustment screws 119, the adjustment screw 119 is a flow guide tube 103 at a constant angular interval in the middle portion of the outer peripheral surface of the case 105 By fastening so as to penetrate horizontally toward the center thereof, the heater disposed below the flow guide tube 103 is restrained from escaping upward, and at the same time, the end surface of each adjustment screw 119 is the flow guide tube 103. By pressing the outer circumferential surface of the rod-shaped temperature sensor 107 disposed perpendicular to the center of the at a predetermined angular interval, the temperature sensor 107 is approximately perpendicular to the center of the flow guide tube 103 Allow it to be centered.

Such an air heater assembly according to the present invention, as shown in Figure 7, may include an installation bracket 127 for coupling with the printing head 100. In addition, correspondingly, the printing head 100 may also include a mounting bracket 133 which is coupled to the rear side thereof and extends to protrude to both left and right sides of the printing head 100 to some extent. Therefore, through direct coupling using a fastening member such as a screw between the mounting bracket 133 and the mounting bracket 127, the air heater assembly 110, 110 'can be easily combined with the printing head 100 integrally. Will be.

On the other hand, the air heater controller (not shown) by comparing the temperature value and the set temperature detected by the head movement sensor (not shown) and the temperature sensor 107 for detecting the moving direction of the printing head 100, A pair of air heater assemblies to adjust the heating amount of the heater, so that the power is connected to only one of the air heater assembly mounted on the opposite side of the printing direction of the printing head 100 being printed according to the information detected by the head movement detecting sensor. (110) 110 includes a microcomputer (not shown) to selectively control the ON / OFF.

In addition, such an air heater controller has a temperature setting switch (not shown) for setting the temperature of the heater 115 on a control panel (not shown) exposed to the outside, and a voltage adjustment switch for adjusting the voltage ( Not shown), and a power on / off switch (not shown). When the switches as described above are provided, the microcomputer provided in the air heater controller reflects the temperature value detected by the temperature sensor 107 and the heaters 115 by reflecting the set values by the switches as described above. That is, the electricity supplied to the heating wire 113 is appropriately controlled. For reference, by providing the temperature sensor 107 and the microcomputer interacting with it, it is possible to prevent overheating of the heater 115, it is possible to always supply a hot air of a uniform temperature.

Hereinafter, the operation of the digital printing machine having the hot air ink drying apparatus according to the present invention will be described.

The digital printing machine according to the present invention, like the digital printing machine according to the prior art, has a media (not shown) through the gap between the carriage 5 and the base 1 from the rear to the front (in the direction of the arrow in FIG. 2). Is transported at a constant speed, printing is performed by spraying ink to the media through a nozzle provided in accordance with the output signal while reciprocating from side to side while the printing head 100 is restrained by the carriage 5.

In addition, at the same time as the printing, the hot air ink drying apparatus according to the present invention also operates to supply hot air locally toward the ink sprayed on the media, so that the ink can be quickly dried on the media. In more detail, the air heater assembly 110, 110 'according to the present invention, the lower portion of the flow guide tube 103 by the heater 115 for generating heat and the blowing fan 125 for causing forced flow By intensively supplying the hot air discharged to the restricted area where the ink is injected, the ink can be quickly dried by the hot air.

In addition, during the printing process, the air heater controller moves only the air heater assembly 110 ′ on the right side when the printing head 100 moves to the left side, and moves the left side when the printing head 100 moves to the right side. Only the air heater assembly 110 is controlled to operate. In detail, the air heater controller may selectively operate only one of the air heater assemblies 110 and 110 ′ according to the moving direction of the printing head 100 through the microcomputer according to the information detected by the provided head movement sensor. Make sure As a result, the ink sprayed on the media by the hot air can be quickly dried, but the hot air is not supplied to the position where the ink is to be ejected, but is supplied while following the position where the ink has already been ejected. In addition, as the flow guide tube 103 is formed in a tapered shape, the ink can be dried more quickly by supplying hot air intensively in a limited area. By supplying hot air in a manner that traces traces of ink ejected from the nozzle and provides hot air intensively in a limited area, it is possible to minimize the influence of hot air on the nozzle where the ink is ejected. The ink is solidified around the nozzle to prevent the nozzle from clogging due to the effect of the ink, and as soon as the ink falls into the media, the ink can be quickly dried by hot air without spreading or spreading.

On the other hand, when the print job is finished, the air heater controller, the two air heater assembly (110, 110 ') located on the left and right sides of the printing head 100 is controlled to stop the operation, even in this case the heater 115 The power connected to the immediately cut off, the blower fan 125 is controlled to stop after further maintaining the operation state for a certain time so that the air heater assembly (110, 110 ') is sufficiently cooled.

By providing a digital printing device having a hot air ink drying apparatus according to the present invention according to the present invention as described above, regardless of the type of media, even if not having a separate structure having a large space and cost burden, hot air type The ink sprayed by the ink drying apparatus can be quickly dried or cured.

Therefore, it is possible to form accurate dot dots without bleeding or spreading at the position where ink is ejected, while maintaining the characteristics according to the material of the media, thereby realizing delicate high quality printing. In other words, even in the case of media with absorbent material, it is possible to print without deterioration.

In addition, the printing speed can be further increased, thus enabling a marked improvement in productivity.

In addition, any type of ink has the effect of shortening the drying or curing time by hot air, thereby obtaining an effect of rapidly drying or curing the ink irrespective of the type of ink used. In the case of using the ink, the effect by the hot air ink drying apparatus according to the present invention will be more prominent.

While the invention has been shown and described with respect to specific embodiments thereof, those skilled in the art will recognize that various changes and modifications can be made without departing from the spirit and scope of the invention as set forth in the appended claims. Anyone can easily know.

Claims (3)

A plate-shaped base that is formed to be long left and right, a pair of left and right supports that support the base in a structure supporting from both sides, and a transfer table formed to be long to the left and right to be arranged side by side with a predetermined gap on the base; A printing head which is mounted to reciprocate from side to side in the restraint of the carriage and has a plurality of nozzles for injecting ink into the media passing downward, and the printing head is moved from side to side on the carriage; A digital printing machine comprising a conveying means for providing a driving force to reciprocate, A case in which a tapered flow guide tube having a diameter gradually decreasing from top to bottom is formed therein; A heater which is formed in a coil spring shape of which the diameter gradually decreases from top to bottom so as to correspond to the bottom shape of the flow guide tube and is disposed below the inside of the flow guide tube; A temperature sensor disposed at the center of the flow guide tube, and It is composed of a configuration including a blowing fan coupled to the upper case to generate forced flow in the flow guide tube, A pair of air heater assemblies mounted on left and right sides of the printing head, respectively; And A head movement sensor for sensing a movement direction of the printing head, and The heating value of each of the heaters is adjusted by comparing the temperature value detected by the temperature sensor with a set temperature, and the one mounted on the opposite side of the printing direction of the printing head being printed according to the information detected by the head movement sensor. And an air heater controller including a microcomputer to selectively turn on / off the pair of air heater assemblies so that power is connected only to the air heater assembly. The method of claim 1, The heater, the heating wire that generates heat when the power is connected, and It is formed in a coil spring shape of a gradually decreasing diameter from top to bottom, and the lower end side by side in a state separated from each other from the upper end formed in the opening side is formed into the inlet side and the outlet side so that the heating wire is built therein And a hot wire protecting member having a hot wire receiving tube extending from the lower end to a side thereof connected to each other at a lower end thereof, wherein the hot printing ink drying apparatus comprises a hot air ink drying device. The method of claim 2, The hot wire receiving tube is a digital printing machine having a hot-air ink drying device, characterized in that the hot wire is sealed in a vacuum state built-in.

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