JP6844194B2 - Drying equipment, transfer system - Google Patents

Description

The present invention relates to a drying device and a transport system.

Conventionally known, an inkjet printer that ejects droplets of ink or the like (ink droplets) from a nozzle of a liquid injection head and records an image, characters, or the like on a recording medium such as printing paper. The inkjet printer is provided with a transport path for transporting a recording medium which is an object to be transported. Several types of inkjet printers are known. For example, serial printers and line printers. In the transport path, the serial printer ejects ink while moving the recording head in the main scanning direction, which is a direction orthogonal to the transport direction of the transported object, and transports the ink in the sub-scanning direction, which is the transport direction of the transported object. In combination with, a printing operation on a recording medium is executed. A line printer has a line head in which recording heads are arranged side by side in the main scanning direction in order to print in a print width that matches the width dimension of the recording medium. The printing operation is executed while moving the object to be transported relative to the line head.

In recent years, in inkjet printers, the printing image quality is improved and the printing operation speed is increased by finely controlling the ink droplet ejection timing and the ink droplet size. However, since it is a method of dropping droplets (liquid) onto a recording medium to form an image, as a problem for improving image quality and speeding up, droplets adhering to the recording medium move on the surface of the recording medium and are adjacent to each other. It is known that the problem is that it is mixed with the droplets that form. In particular, in the case of a recording medium having a coat layer or the like, the droplets do not easily penetrate into the recording medium, and color mixing with adjacent ink droplets of different colors tends to occur. When color mixing occurs, a phenomenon such as color bleeding in which the color boundary becomes unclear tends to occur. When color bleeding occurs in the print result, the sharpness of the printed image is lowered. That is, the print image quality is deteriorated.

Further, when the printing operation is speeded up, the recording medium is sent from the recording medium to the post-processing of the printing operation while the ink permeates the recording medium and the ink droplets adhering to the recording medium are not sufficiently dried. Problems such as ink transfer (picking) to the transfer roller and ink transfer (blocking) between overlapping recording media in the transfer path are likely to occur. As measures against picking and blocking, a technique of applying a powder material to prevent ink transfer after printing and a technique of arranging a drying device in the downstream process of the printing unit to dry the ink on the printing surface of the recording medium are known. ..

Among these, as a technique for drying ink, a method of arranging a heating roller having a built-in heat generation source inside a transfer roller forming a transfer path is known. The method using a heating roller is a method in which a recording medium to be dried is brought into contact with a recording medium to be dried while being wound around a certain angle on the outer peripheral surface of the heating roller, and the ink is dried by heating at the time of this contact.

By the way, in the heating roller method, not only the water content but also the solvent is evaporated by heating the ink at about 100 ° C. to 200 ° C. in the heating roller portion. In order to dry the solvent and moisture in this way, it is necessary to supply the required amount of heat within the time of contact with the paper. Therefore, when using a recording medium having a high basis weight which requires a large amount of heat, or when increasing the transport speed of the recording medium, it is necessary to use a plurality of heating rollers. In this case, the device size and paper operability can be taken into consideration by arranging the heating rollers in a staggered arrangement.

In a drying device in which a plurality of heating rollers are arranged in a staggered manner, the solvent and moisture vaporized and vaporized by the heating rollers arranged below move upward along with the updraft in the drying device. In this case, the heating roller arranged above is surrounded by an atmosphere such as a solvent vaporized by the heating roller below. The heating roller is provided with a guide for guiding the recording medium so that the recording medium is conveyed without deviating from the transfer path when the recording medium is loaded or conveyed. From the inside of this guide, the solvent evaporates as described above. The vapor of such a solvent can cause problems such as condensation on the guide and rusting of the guide.

Although it is not a technique for preventing the adhesion of solvent vapor to the guide, in an image forming apparatus equipped with a fixing device that fixes an unfixed toner image on a recording medium by at least heating, a technique for preventing water droplets from adhering to the recording medium after fixing is available. It is known (see, for example, Patent Document 1).

The guide disclosed in Patent Document 1 is a wire-like member having a convex cross-sectional shape that extends at least in a direction having a transport direction component of recording and protrudes from the transport path side of the recording medium without any corners. And a holder that supports the wire-shaped members so as to be spaced apart from each other on the surface along the transport path.

The guides installed around the conventional heating rollers are in a state in which the guides themselves interfere with the movement of the solvent and moisture vaporized by the heating rollers to the upper part of the machine. On the other hand, on the outside of the guide, the vaporized solvent and moisture rising from the periphery of the heating roller directly underneath are directly received. According to such a state, the solvent and water condense on the inside and outside of the guide due to the temperature difference between the guide and the steam.

Even if a wire member is used as in the guide disclosed in Patent Document 1, in a drying device that supplies a required amount of heat to a heating roller used for drying continuous paper, usually recording is performed on a transport roller including the heating roller. A guide is installed to cover the part around which the medium is wound. When continuous paper is wound around a heating roller, moist air containing vaporized solvent and moisture is always generated from the wound portion. This moist air needs to be exhausted from a drying chamber in which a winding portion and a heating roller are installed.

In this case, if there is a transport path through which the recording medium passes in the direction in which the moist air moves, the moist air generated below the transport path adheres to the recording medium passing through the upper transport path again to generate water droplets. become. In this case, even if the guide is composed of a wire member and an attempt is made to efficiently remove moist air from the winding portion, the problem cannot be solved.

Therefore, an object of the present invention is to prevent dew condensation that occurs in the recording medium and the guide in the transport path due to the vaporization of the solvent or water from the recording medium in the transport path.

In order to solve the above problems, in one aspect of the present invention, a transport path for winding and heating and transporting the object to be transported in the continuous book is formed by an arrangement of rollers including at least one heating roller, and above the transport path. The drying device is provided with an exhaust means, and the transport paths are arranged at a paired position so as to direct the transported object from upstream to downstream while folding back the transported object to an appropriate length. An interval changing mechanism for changing the interval in the horizontal direction of the rollers, which is formed by the arrangement of the rollers and is arranged relative to the paired position where the transport path is folded back, the basis weight of the transported object, and the subject. The rollers face each other based on any of the print area and print density to be printed on the transported object, the transport speed of the transported object, the temperature of the heating roller, and the temperature and humidity in the chamber in which the heating roller is arranged. The control means for changing the interval and the first roller, the second roller, the (n-1) roller, and the n-roller sequentially from the lower side in the vertical direction of the transfer path, and from the lower side in the vertical direction of the transfer path. Assuming that the heating roller arranged at the m-th position is the m-th roller, the (m + 1) roller has a vertical tangent line on the winding side of the object to be transported so as to be located on the counter-winding side of the m-th roller. In addition, the distance between the roller and the pair of rollers is set . However, m and n are integers, and n> m ≧ 1 and n ≧ 2.

According to the present invention, it is possible to prevent dew condensation that occurs in the recording medium or the guide in the troublesome path due to the vaporization of the solvent or water from the recording medium in the transport path.

It is a figure which shows the whole structure of the drying apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the transport system which concerns on embodiment of this invention which arranged the drying apparatus on the downstream side of a printing apparatus. It is a block diagram which shows the control composition which concerns on embodiment of the transport system. It is explanatory drawing which cross-sections in the center of the chamber of the drying part in the drying apparatus which concerns on FIG. 1, and illustrates the air flow of a drying part. It is a perspective view which shows the example of the 1st heating roller of FIG. 1 and the transport guide arranged around it. It is a perspective view which shows another example of the transport guide arranged around the 1st heating roller of FIG. It is a perspective view which shows the example of the proximity separation mechanism provided in the drying apparatus which concerns on this embodiment. It is a figure which shows the whole structure of the drying apparatus which concerns on another embodiment of this invention. It is a figure explaining an example of arrangement of rollers in the drying apparatus which concerns on this invention. It is a figure which defines the term used for the arrangement explanation of the roller which concerns on this embodiment. It is a figure explaining another example of arrangement of a roller in the drying apparatus which concerns on this invention. It is a figure explaining another example of arrangement of a roller in the drying apparatus which concerns on this invention.

The present invention relates to a drying device that dries while transporting an object to be transported. In the embodiment described below, a continuous long sheet-like member is exemplified as the object to be transported. Therefore, in the drying device of the present embodiment, the object to be transported is continuously transported through the transport path formed inside. The drying apparatus according to the present invention includes a heating means in the transport member in a transport path formed by the transport members arranged in a predetermined arrangement. The object to be transported is transported while being dried using the heat from this heating means. Therefore, the object to be transported does not have to be continuous as long as it is transported while being heated by the transport member, and can be applied to a sheet-shaped member formed with a predetermined dimensional length.

The transport path provided in the drying apparatus according to the present invention is formed by arranging a plurality of transport rollers, which are transport members. A part or all of the transporting member is a heating transport roller provided with heating means. The drying apparatus according to the present invention prevents the moist air generated around the heating transport roller from adhering to other heating transport rollers and their surrounding parts in the transport path that is the drying step of the object to be transported, and prevents the moist air from adhering to other heating transport rollers and surrounding parts. One of the gist is that exhaust can be done efficiently.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing an overall configuration of a drying device 1 according to the present embodiment. As shown in FIG. 1, the drying device 1 includes a buffer 3, a drying unit 5, a cooling unit 7, a transport roller 9, and a nip roller 11 as its basic internal configuration. With these configurations, a transport path for the recording medium 13 inside the drying device 1 is formed. The recording medium 13 is an example of an object to be transported, and is a long sheet-like member. The recording medium 13 is a so-called continuous paper. The recording medium 13 is mainly conveyed by rotational drive of a transfer roller 9 arranged on the downstream side of the transfer path in the drying device 1. In the drying device 1 shown in FIG. 1, the recording medium 13 is discharged from the buffer 3 arranged below the upstream side (the right side of the paper surface in FIG. 1) to the downstream side (the left side of the paper surface in FIG. 1). It is conveyed toward the paper guide roller 15. That is, in FIG. 1, the recording medium 13 enters the inside of the drying device 1 from the lower right and exits from the lower left. In this way, a transport path is formed so as to transport the recording medium 13 in a predetermined direction. The rollers other than the transport roller 9 may be idler rollers that do not have a drive source, or rollers that have a drive source.

The buffer 3 is provided at the entrance to the drying device 1. The buffer 3 adjusts the amount of the transfer buffer of the recording medium 13 when the recording medium 13 is conveyed. The amount of the transfer buffer in the buffer 3 is adjusted by controlling the rotation speed of the transfer roller 9. That is, by controlling the rotation speed of the transport roller 9, it is possible to form a state in which the transport speed of the recording medium 13 is maintained at a constant speed. The buffer 3 is provided with a movable member 17 to which two first buffer rollers 17a and a second buffer roller 17b are arranged so as to be movable up and down. The amount of transport buffer is changed depending on the vertical position of the movable member 17.

The drying section 5 is located on the downstream side of the buffer 3, and the recording medium 13 that has passed through the buffer 3 enters the drying section 5. The area occupied by the drying portion 5 is closed by the chamber 6. The chamber 6 is insulated from the surroundings by a heat insulating material. Therefore, the space inside the chamber 6 of the drying portion 5 is hotter than the surroundings. A heating roller 19 which is a plurality of transporting members is arranged in this space.

A part of the heating roller 19 forming the transport path may be a transport roller without a heating means. The space inside the chamber 6 is heated by the heat generated by the heating roller 19. Therefore, a dedicated space heating device is not required in the drying unit 5. The heating roller 19 is provided with a heating element such as a halogen lamp inside, and is configured so that the heat of the heating element is transferred to the outer periphery of the roller.

A plurality of heating rollers 19 are arranged in the chamber 6 of the drying unit 5. For example, as shown in FIG. 1, a first heating roller 19a, a second heating roller 19b, a third heating roller 19c, a fourth heating roller 19d, a fifth heating roller 19e, a sixth heating roller 19f, and a seventh heating roller 19g. The heating rollers 19 made of the above are arranged in a predetermined arrangement. The heating rollers 19 are arranged in a staggered manner as shown in FIG. 1 when viewed from the side of the recording medium 13 in the transport direction.

As shown in FIG. 1, the transport path of the recording medium 13 changes the direction of the recording medium 13 by folding back the transport direction of the recording medium 13 by approximately 180 degrees with an appropriate length, and moves the recording medium 13 from upstream to downstream of the transport path. It is formed so as to face. That is, the heating roller 19 is arranged at a position in the transport path where the transport direction of the recording medium 13 is folded back. In the description of the present embodiment, when the plurality of heating rollers 19 illustrated above are described without distinction, the notation "heating roller 19" is simply used.

Next, the transport path formed inside the drying portion 5 will be described. As shown in FIG. 1, the recording medium 13 that has entered the drying unit 5 from the buffer 3 is wound around the outer circumference of the first heating roller 19a and conveyed in the horizontal direction. Next, the recording medium 13 is wound around the outer circumference of the second heating roller 19b arranged on the inner side of the drying portion 5 in the horizontal direction of the first heating roller 19a, and the recording medium 13 is in the traveling direction so far. It is transported by being folded back in the opposite traveling direction (transportation direction). When passing through the second heating roller 19b, it moves upward in the vertical direction of the transport path. Next, the recording medium 13 is wound around the outside of the third heating roller 19c arranged in the horizontal direction of the second heating roller 19b and on the outer side of the drying portion 5, and the recording medium 13 is again inside the drying portion 5. It is transported horizontally to the side.

After that, the recording medium 13 is conveyed downstream while repeating the horizontal folded transfer. As described above, the transport path formed inside the drying portion 5 is formed so as to repeatedly move the recording medium 13 in the horizontal direction by the heating roller 19 and to move in the vertical direction while folding back the transfer path.

Since the recording medium 13 is conveyed while being in contact with the heating roller 19 forming the transfer path, the recording medium 13 is dried by the heat from the heating roller 19.

Next, the arrangement of the heating rollers 19 forming the transport path of the recording medium 13 will be described in more detail. In the following description, the expression "winding side, anti-wrapping side of the recording medium 13" is used in the description of the position of the heating roller 19. Therefore, first, the "winding side of the recording medium 13" and the "anti-wrapping side of the recording medium 13" will be described. FIG. 10 is an enlarged view of a part of the transport path formed by the arrangement of the heating rollers 19. As shown in FIG. 10, the outer periphery of the heating roller 19 where the recording medium 13 comes into contact with the heating roller 19 and changes the transport direction is referred to as a “winding portion 190”. As for the transport direction of the recording medium 13, the transport direction in the horizontal direction is changed to the opposite direction with the winding portion 190 as a base point. In the winding portion 190, the side of the outer circumference of the heating roller 19 in contact with the recording medium 13 is referred to as the “winding side”. Further, the opposite side of the winding side is referred to as the "anti-winding side". At this time, the recording medium 13 is moved in the height direction corresponding to at least the diameter of the heating roller 19.

As described above, the heating rollers 19 forming the transport path are arranged in multiple stages vertically separated from the upstream to the downstream in the transport direction of the recording medium 13 (see FIG. 1). In other words, assuming that the pair of heating rollers 19 arranged at positions where the transport direction of the recording medium 13 is folded back is one stage, these horizontal pairs are arranged in multiple stages inside the drying portion 5. ing. At this time, the arrangement of at least one of the heating rollers 19 of each stage is adjusted so that the overlapping with the heating rollers 19 of the other stages in the vertical direction is reduced in the vertical direction.

For example, as shown in FIG. 1, taking the positions of the first heating roller 19a arranged at the uppermost stream and the third heating roller 19c arranged above the first heating roller 19a as an example, the transport formed by these is taken as an example. The arrangement of the first heating roller 19a and the third heating roller 19c is adjusted so as to be in different positions in the horizontal direction of the path.

Next, with reference to FIG. 9, the arrangement relationship of the heating rollers 19 in the transport path will be described in more detail. FIG. 9 shows only the arrangement relationship of the heating rollers 19 in the drying portion 5. In FIG. 9, among the heating rollers 19, the one arranged in the uppermost stream is referred to as a “first roller 191”. Further, the heating roller 19 arranged downstream of the first roller 191 and directly above the first roller 191 is referred to as a "second roller 192". Similarly, the one arranged at the most downstream of the transport path is referred to as the "nth roller 19n". Note that n is an integer of 2 or more.

Focusing on the positional relationship between the first roller 191 and the second roller 192 in FIG. 9, the first roller 191 and the second roller 192 have vertical tangents on the winding side of the recording medium 13 in the vertical direction of the transport path. They are arranged so that they do not overlap. In FIG. 9, the vertical tangent on the winding side of the second roller 192 is moved by a distance corresponding to L1 in the horizontal direction from the vertical tangent on the winding side of the first roller 191.

Similarly, in the nth roller 19n and the first (n-1) roller 19 (n-1) arranged downstream and downward one step before the nth roller, the vertical tangents on the winding side do not overlap each other, and the second roller 19n The vertical tangent of the n-roller 19n is moved by a distance corresponding to L (n-1) from the vertical tangent of the (n-1) th roller 19 (n-1).

In other words, the transport path formed inside the drying unit 5 is formed so that the heating roller 19 is arranged at a position where the horizontal transport of the recording medium 13 is folded back, and the recording medium 13 is transported from upstream to downstream. ing. A transport path is formed so that each time the recording medium 13 is folded back by the heating roller 19, the recording medium 13 moves upward in the vertical direction. Further, the heating rollers 19 corresponding to the vertical relationship in the vertical direction of the transport path are arranged at positions where the vertical tangents on the winding side of the recording medium 13 do not overlap each other.

In other words, when the drying portion 5 is viewed from above, the heating roller 19 is located on the central side of the chamber 6 as a relative position so that the heating roller on the lower side in the vertical direction of the transport path is located on the central side of the chamber 6 as compared with the heating roller on the upper side in the vertical direction. It is placed in a close position.

As described above, the heating rollers 19 forming the transport path have different winding side end faces of the recording media 13 between the heating rollers 19 arranged at the same side positions in the vertical direction from the upstream in the transport direction to the downstream in the transport direction. It is arranged so that it is in a position. When one heating roller 19 arranged in the transport path is used as a base point, the other heating roller 19 located downstream of the one heating roller 19 and arranged on the same side in the vertical direction is in one heating roller. It is placed at the position moved to the anti-winding side. Further, the other heating rollers 19 that are upstream of one heating roller and are arranged on the same side in the vertical direction are arranged at positions that are moved horizontally outward from the winding side of the one heating roller.

In other words, with reference to FIGS. 1 and 9, the transport path formed inside the drying portion 5 is formed so as to move the recording medium 13 in the vertical direction while folding back in the horizontal direction. The horizontal folding of the recording medium 13 is performed by winding the recording medium 13 around the outer circumference of the heating roller 19. The length of the horizontal transport of the recording medium 13 becomes shorter as the transport path goes in the vertical direction. That is, the transport length of the recording medium 13 in the horizontal direction is longer in the upstream direction than in the downstream direction. This is because the heating roller 19 is moved so that the vertical tangents indicating the positions of the winding side side surfaces of the recording medium 13 on the heating roller 19 do not overlap each other upstream and downstream. Regarding the heating rollers 19 located at the positions where the recording medium 13 is folded back in the same horizontal direction, the heating rollers 19 arranged upstream are inside the drying portion 5 more than the heating rollers 19 arranged downstream. It comes to the outside in space.

As described above, the heating rollers 19 are arranged so that the winding side end face positions of the heating rollers 19 facing each other in the vertical direction do not overlap each other from the upstream side to the downstream side of the transport path. Due to such an arrangement of the heating rollers 19, when the moist air generated in the heating rollers 19 on the downstream side of the transport path rises in the space inside the chamber 6, it does not come into contact with (does not hit) the heating rollers 19 above. , Exhausted to the outside of the chamber 6. This makes it possible to prevent the occurrence of dew condensation on the heating roller 19.

In the embodiment described above, the case where all the rollers are heating rollers 19 has been illustrated. However, the present invention is not limited to this, and at least one roller may be the heating roller 19. Temporarily, one roller is a heating roller 19, and the heating roller 19 is arranged between the first roller 191 and the nth roller 19n in the mth position counting from the first roller 191 in the vertical direction. m roller 19m ".

In this case, the m-th heating roller 19 is on the horizontal winding side with respect to the vertical tangent on the winding side of the recording medium 13 with respect to the vertical tangent on the winding side of the roller arranged at the (m + 1) th position. It is arranged so that it is in the position moved to. As a result, when the moist air generated in the heating roller 19 (mth) vertically below the transfer path rises in the space inside the chamber 6, the heating roller 19 (m + 1) vertically above the transfer path It is exhausted to the outside of the chamber 6 without contacting (not hitting) the third). Therefore, an effect similar to the effect already described can be obtained.

Even when there are a plurality of heating rollers 19, the vertical tangents on the winding side of each heating roller 19 (mth) are the rollers arranged next (the m + 1th heating roller 19 or the transport roller). It is arranged so that it is moved to the horizontal winding side with respect to the vertical tangent of the winding side.

As described above, when the rollers having a heating function and the rollers without a heating function are arranged in a mixed manner, they are arranged at least in the (m + 1) th position with respect to the heating rollers 19 arranged in the mth position. The third (m + 1) th roller is arranged so that the vertical tangent line on the winding side of the roller is moved to the winding side in the horizontal direction.

In the space between the plurality of heating rollers 19, drying is performed by convective heat transfer by high temperature air. The upstream side of the heating roller 19 requires a higher heating capacity. This is because the heat generated by the heating roller 19 on the upstream side is taken away by the recording medium 13 which is the base material instead of the ink, and the heat is used for the ink when the temperature of the recording medium 13 becomes a certain temperature or higher. Because it is a case.

Therefore, in the case of the heating roller 19 shown in FIG. 1, the two heating rollers 19 on the upstream side of the first heating roller 19a and the second heating roller 19b are for raising the temperature of the recording medium 13. Yes, they are equipped with the ability to heat the recording medium 13 with a heat capacity sufficient to raise the temperature.

Since the drying conditions differ depending on the weighing of the recording medium 13, the printing area and the printing density, and the temperature and humidity in the chamber 6, the heating capacity of the heating roller 19 is set according to the basis weight and the like. ..

The drying device 1 includes a proximity separation mechanism 199 that makes it possible to move the position of the end face on the winding side in the horizontal direction of the heating roller 19. The proximity separation mechanism 199 changes the distance between the winding side end face positions of the heating rollers 19 which are arranged in pairs in the horizontal direction of the transport path of the recording medium 13 and which are in a horizontally opposed relationship with each other. It is an interval change mechanism. By this proximity separation mechanism 199, the heating rollers 19 can be adjusted so as to be arranged so as not to overlap each other in the vertical direction as described above.

The structure of the proximity separation mechanism 199 will be described with reference to FIG. 7. The proximity separation mechanism 199 is provided in each of the heating rollers 19 constituting the transport path. The proximity separation mechanism 199 is configured by connecting a set of heating rollers 19 to a moving belt 197 hung between a pair of rotary drive pulleys 198 by a connecting metal fitting 196. Then, when one of the rotary drive pulleys 198 is rotationally driven by the horizontal movement motor 361, the corresponding ones of the heating rollers 19 connected to the moving belt 197 move in the directions of approaching and separating from each other.

For example, when the rotary drive pulley 198 is rotated in the counterclockwise direction by the horizontal movement motor 361 as shown in FIG. 7, the first heating roller 19a and the second heating roller 19b move in a direction approaching each other. As a matter of course, if the rotation direction of the horizontal movement motor 361 is set counterclockwise on the paper surface, the first heating roller 19a and the second heating roller 19b move in directions far from each other.

The amount of movement of the heating roller 19 is set by the microcomputer unit 30 (FIG. 3) described later, and is performed by the microcomputer unit 30 driving and controlling the horizontal movement motor 361. The lowermost first heating roller 19a and the second heating roller 19b may be fixed, and the intervals of the heating rollers 19 on the first heating roller 19a in the horizontal direction may be controlled respectively. The latter is advantageous in terms of cost because one drive mechanism can be omitted.

Return to FIG. The recording medium 13 that has advanced from the drying unit 5 is conveyed to the cooling unit 7 composed of eight guide rollers arranged alternately in the vertical direction. The recording medium 13 is cooled by being conveyed between the guide rollers. In this space (cooling unit 7), the temperature of the recording medium 13 can be controlled by blowing outside air and changing the transport distance. The transport distance is changed, for example, by changing the vertical positions of the lower four guide rollers relative to the upper four guide rollers.

FIG. 2 is a diagram showing a configuration of a transport system 100 in which the drying device 1 is arranged on the downstream side of the printing device 21.

In the transfer system 100 shown in FIG. 2, the recording medium 13 that has entered the printing apparatus 21 is supplied to the printing unit 27 via the first transfer roller 23a and the first guide roller 25a. The printing unit 27 has inkjet heads 27Y, 27M, 27C, 27K for ejecting Y, M, C, and K inks. The gap between the inkjet heads 27Y, 27M, 27C, 27K and the paper is about 1 to 2 mm. Further, the recording medium 13 that has passed through the printing unit 27 is guided to the drying device 1 via the second guide roller 25b and the second transport roller 23b on the downstream side.

The printing apparatus 21 has a printing surface drying unit 29 on the downstream side of the printing unit 27. This is for suppressing ink transfer (picking) when the ink ejected on the printing surface touches various rollers, and does not suppress blocking. Picking occurs in an undried state in which ink transfer occurs even with short-term contact. In blocking, although the ink is dried to the extent that picking does not occur, the printing surface of the recording medium 13 (the surface to which the ink adheres) is formed by stacking the recording media 13 or winding the recording medium 13. This is a phenomenon in which ink transfer adheres to other than the printed surface when a high pressure is applied to the ink.

The division of roles between the printing device 21 and the drying device 1 in the transport system 100 according to the present embodiment is such that picking is suppressed in the printing device 21 and blocking is suppressed in the drying device 1.

FIG. 3 is a block diagram showing a control configuration of the transport system 100 according to FIG. The reference numerals are given so as to correspond to the mechanical configuration of FIG.

In FIG. 3, the drying device 1 includes a microcomputer unit 30 for controlling the device, an operation panel unit 32 operated by an operator, a transfer roller unit 34 (convey roller 9 and nip roller 11), an interval control unit 36, a heating roller unit 38, and a transfer. Each device and sensor of each unit including the speed receiving unit 40 is connected by a bus 42 via an I / O interface.

The microcomputer unit 30 that functions as a transfer control unit instructs the control of each device unit of the drying device 1, performs the calculation necessary for the control, the CPU 301, the ROM 302 that stores the program executed by the CPU 301, and the calculation result. It is composed of a RAM 303 that temporarily stores the above.

The operation panel unit 32 lights up according to the state of the drying device 1, the menu item being operated by the operator, the LCD (Liquid Crystal Display) 321 that displays information such as the set temperature of the heating roller 19, and the state of the drying device 1. It is composed of an LED (Light Emitted Diode) 322 that changes the blinking pattern and informs the operator of the state of the drying device 1, and a switch 323 for the operator to operate the drying device 1.

The transfer roller unit 34 controls the transfer motor 341 and the brake 342 that rotationally drive the heating roller 19. The drying device 1 and the printing device 21, and the drying device 1 and the control device 50 of the transport system 100 are each connected by an I / F cable, and the information on the transport speed of the recording medium 13 is transmitted from the printing device 21 to the drying device 1. It is transmitted via the F cable. The transfer speed information is converted into speed data in a form used by the transfer speed receiving unit 40 for controlling the transfer motor 341 of the heating roller 19, and is used for speed control of the transfer roller unit 34. Further, the control device 50 transmits information on the weighing, printing area, and print density of the recording medium 13 to be printed, and is used for controlling the interval of the heating rollers 19.

The interval control unit 36 includes a horizontal movement motor 361 and a plurality of position detection sensors 362. The position detection sensor 362 detects each position of the heating roller 19 and notifies the microcomputer unit 30 of the position. The microcomputer unit 30 drives and controls the horizontal movement motor 361 based on the respective positions of the heating rollers 19, the weighing of the recording medium 13, the print area and the print density, and the temperature and humidity in the chamber 6. The drive control of the horizontal movement motor 361 by the microcomputer unit 30 adjusts the distance between the rotation centers of the heating rollers 19 which are opposed to each other in the horizontal direction. That is, the arrangement of the heating rollers 19 is adjusted by the microcomputer unit 30. The horizontal movement motor 361 is configured to independently control the heating rollers 19 in each pair of the heating rollers 19 that are opposed to each other.

The heating roller unit 38 includes a heater lamp 381, a temperature detection sensor 282, and a humidity detection sensor 283. The temperature detection sensor 282 detects the temperature of each heating roller 19 and the temperature of a preset location in the chamber 6, and the humidity detection sensor 283 detects the humidity of the preset location, for example, the humidity of the upper part of the chamber 6. , Sent to the microcomputer unit 30.

The microcomputer unit 30 controls the lighting of the heater lamp 381 based on the sent temperature. Further, the microcomputer unit 30 is in each of the heating rollers 19 based on the parameters sent from the control device 50 of the printing system included in the transport system 100 including the printing device 21. Calculate the appropriate spacing in the horizontal direction of the transport path. Here, the parameters are weighing, print area, and print density information of the recording medium 13, and temperature information and humidity information in the chamber 6. Based on the calculated spacing, the horizontal movement motor 361 is driven to move the heating rollers 19 to positions at appropriate spacing in each.

The position of the end face on the winding side of the heating roller 19 is data in which the relationship between the weighing of the recording medium 13, the print area, the print density, the transport speed, and the temperature and humidity in the chamber 6 is parameterized in advance using an actual machine. Calculated and set based on the table. This data table is stored in the RAM 303. The microcomputer unit 30 refers to a data table stored in the RAM 303 based on a program that controls the position of the heating roller 19, and calculates change conditions corresponding to changes in parameters such as weighing of the recording medium 13. Based on this change condition, the microcomputer unit 30 executes a process of setting the winding side end face position of the heating roller 19. As a result of this processing, in the drying apparatus 1, the position of the heating roller 19 is set so that the horizontal spacing of the heating rollers 19 becomes appropriate according to the progress of the printing process on the recording medium 13. As described above, according to the drying device 1 according to the present embodiment, the drying unit 5 can be controlled so that picking and blocking do not occur.

Here, an example of a data table, which is a change condition used for setting the winding side end face position in the heating roller 19, will be described with reference to Table 1 below.

The “level” shown in Table 1 is a parameter for setting the winding side end face position of the heating roller 19. The larger the number based on this level, the wider the interval between the winding side end face positions on the downstream side in the transport direction in the arrangement of the heating rollers 19. That is, as the number based on the level increases, the overlap between the heating roller 19 on the upstream side in the transport direction and the heating roller 19 on the downstream side in the transport direction in the arrangement of the heating rollers 19 decreases in the vertical direction. As a result, the upward flow of the moist air generated in the heating roller 19 can be made efficient.

In Table 1, for example, when changing the position of the end face on the winding side of the object to be transported in the horizontal direction of the heating roller 19 in the print area (hereinafter, referred to as “roller end face position”), the print area is divided into five stages. , The case where the print area is the largest is set to "5", and the case where the print area is the smallest is set to "1". That is, when the printing area is the largest, the roller end face position is such that the end face position on the downstream side in the transport direction is made wider and the overlapping of the heating rollers 19 in the vertical direction of the meandering transport path is reduced, so that the wet air Improve the upward flow of. This is because the larger the printed area, the larger the amount of ink and the larger the moist air during drying.

Similarly, the print density is also divided into five stages, and the case where the print density is the darkest is set to "5", and the case where the print density is the lightest is set to "1". The arrangement of the heating rollers 19 corresponding to each number is the same as in the case of the printing area. That is, the roller end face position when the print density is the highest is above the moist air by making the end face position on the downstream side in the transport direction wider and reducing the overlap of the heating rollers 19 in the vertical direction of the transport path. Improve the flow to. This is because the higher the print density, the larger the amount of ink and the larger the amount of moist air during drying.

Similarly, the printing speed is also divided into five stages, and when the printing speed is the fastest, it is set to "5", and when the printing speed is the slowest, it is set to "1". The arrangement of the heating rollers 19 corresponding to each number is the same as in the case of the print area and the print density. That is, the roller end face position when the printing speed is the fastest is such that the end face position on the downstream side in the transport direction is made wider and the overlapping of the heating rollers 19 in the vertical direction of the transport path is lessened, so that the wet air Improve the upward flow. This is because the faster the printing speed, the larger the amount of processing per unit time, and the larger the amount of moist air during drying.

Similarly, the paper weighing, the temperature of the heating roller 19 (roller temperature), and the internal temperature and humidity of the chamber 6 (chamber temperature and humidity) are also divided into five stages. The arrangement of the heating rollers 19 corresponding to each number is the same as in the case of the print area and the print density. When the paper weighing is heavy, the moisture content in the recording medium 13 increases accordingly, and the moist air during drying increases. Further, when the roller temperature, which is the temperature of the heating roller 19, is high, the amount of moist air during drying increases accordingly, and when the chamber temperature and humidity are high, the amount of moist air during drying increases accordingly.

Further, the roller end face position may be set by combining the levels of a plurality of parameters. For example, when the print area and the print density are combined, the maximum value of the numerical value indicating the level is "10". Therefore, the roller end face position corresponding to the total value of each parameter is set by dividing it between the maximum value and the minimum value of the physical distance of the roller interval. In this case, the parameter used to set the roller end face position is between "2" and "10". Further, the roller end face position may be set by using all the parameters set in the data table. In this case, the maximum value of the numerical value for determining the level is "30" and the minimum value is 6. That is, the roller end face position may be set by dividing into 24 stages from the level "6" to the level "30".

Although the level of each parameter set in the data table is set to 1 to 5 in the present embodiment, weighting may be performed with respect to the level of a specific parameter. For example, when weighting the print area, the maximum value of the level may remain 5 and the maximum value of the print area may be 10 for other items. Further, it may be combined with each of the other items as described above.

FIG. 4 is a cross-sectional view of the chamber 6 of the drying portion 5 provided with the heating roller 19 in the center. The air flow in the drying portion 5 will be described with reference to FIG. Since the temperature of the heating roller 19 is controlled to the set temperature by a non-contact temperature detection sensor (thermopile or the like) 382, it does not overheat. Further, for the same reason, there is no drying defect due to insufficient heating.

The ink printed on the recording medium 13 by the printing unit 27 is heated by the heating roller 19 to become a gas, and is passed through an exhaust duct 8 which is an exhaust means connected above the rear wall 10 of the chamber 6 of the drying unit 5 and is connected to the chamber 6. It is exhausted to the outside (direction of arrow C). At this time, an exhaust fan may be attached to the exhaust duct 8, or a suction device or the like outside the device may be connected.

As described above, the heating rollers 19 are arranged alternately in the horizontal direction, and are gradually arranged inward so as not to overlap in the vertical direction. Further, an exhaust port 12 to which the exhaust duct 8 is connected is arranged above the rear wall 10 of the chamber 6. The steam does not rise straight, but flows between the vertically adjacent recording media 13 which are conveyed in the alternating directions toward the rear wall 10 of the drying portion 5 (direction of arrow A), and then rises and exhaust port. Head to 12 (arrow B direction).

As described above, the heating rollers 19 have a staggered arrangement so as not to overlap with other heating rollers 19 in the vertical direction. Further, the distance between the winding side end face positions between the heating rollers 19 arranged in multiple stages in the vertical direction is in a vertical positional relationship so as to gradually narrow as the transport direction of the recording medium 13 proceeds from upstream to downstream. The heating rollers 19 are arranged so as not to overlap. As a result, even if the moist air generated by the lower heating roller 19 rises, it does not hit the heating roller 19 directly above, and it is possible to prevent the occurrence of dew condensation on the loading guide 20 and the recording medium 13.

FIG. 5 is a perspective view showing the first heating roller 19a and the transport guides arranged around the first heating roller 19a. FIG. 5A is a perspective view illustrating a state in which the loading guide 20, which is a transport guide, is attached to the first heating roller 19a. FIG. 5B is a perspective view illustrating the loading guide 20. 5 (a) and 5 (b) are both perspective views, but the viewpoint directions are different.

As shown in FIG. 5A, a loading guide 20 is attached around the first heating roller 19a and is fixed so as to maintain a predetermined distance from the outer peripheral surface of the first heating roller 19a. As shown in FIG. 5B, the loading guide 20 is composed of a guide 22 and a holder 24. The guide 22 is a guide member formed in a substantially U shape by bending a wire with a curvature corresponding to the curvature of the surface of the heating roller 19, and holds the recording medium 13 by winding it around the first heating roller 19a. Guidance to move in the transport direction of. The base of the guide 22 is supported by the holder 24. The other heating rollers 19 have the same configuration.

With this configuration, the moist air generated around the first heating roller 19a flows upward from between the wires of the guide 22, so that the flow of the moist air is not obstructed. On the other hand, as shown in FIG. 1, the heating roller 19 groups are arranged so that the positions of the side surfaces on the winding side are displaced so that the rotation centers do not overlap each other in the vertical direction. Therefore, the heating roller 19 arranged below in the vertical direction in the transport direction does not hit the heating roller 19 also arranged above, but flows toward the exhaust port 12 as it is. As a matter of course, the moist air generated below the transport path in the vertical direction does not come into contact with the guides 22 of the other heating rollers 19 arranged above the transport path in the vertical direction.

As described above, the exhaust configuration in the drying device 1 has a plurality of effects. Since the guide 22 covering the heating roller 19 has a wire configuration, first, the moist air generated around the heating roller 19 is exhausted by the exhaust equipment without contacting the recording medium 13 and surrounding parts. Will be done. Therefore, it is possible to prevent the occurrence of dew condensation on the guide 22 and surrounding parts. Secondly, since the guide 22 is composed of wires, the surface area is small and the flow of moist air is good. The loading guide 20 is a member that is close to the heating roller 19 and is most likely to cause dew condensation due to the temperature difference between the inside and the outside. Can be prevented.

The guide 22 is not limited to the wire. For example, as shown in FIG. 6, in the loading guide 20a according to another embodiment, the guide 22a and the holder 24b of the heating roller 19 may be used in the same manner as the loading guide 20 described above. The guide 22a included in the loading guide 20a shown in FIG. 6 bends a plate-shaped member such as a sheet metal with a curvature corresponding to the curvature of the surface of the heating roller 19, and has a plurality of ribs at regular intervals in the longitudinal direction of the curved surface. It is a guide member which formed 23. The loading guide 20a also winds the recording medium 13 around a heating roller 19 or the like, holds the recording medium 13, and guides the recording medium 13 so as to move in a predetermined transport direction.

The guide 22a functions as a guide member in which the rib 23 guides the transportation of the recording medium 13, and a ventilation hole 25 is provided in a recessed portion between the rib 23 and the rib 23 by heat transfer from the heating roller 19. It exerts a function of passing the moist air generated from No. 13 ascending. As a result, the moist air is exhausted by the exhaust equipment without coming into contact with the recording medium 13 and surrounding parts. Therefore, it is possible to prevent the occurrence of dew condensation on the loading guide 20a and the surrounding parts.

Further, in the present embodiment, the recording medium 13 is used as the object to be transported, and an inkjet printer is used as the printing device 21 as an example. However, the object to be transported is a long or web-shaped paper or film. Including strips such as. Further, the inkjet printer is exemplified as a typical example of a device for discharging a liquid provided with a liquid discharge head for discharging a liquid, and can be applied to all other types of devices for discharging a liquid.

Further, in the present embodiment, the lower side in the vertical direction of the transport path is the upstream side of the transport, and the upper side is the downstream side of the transport, but as shown in FIG. 8, the positions of the upstream and downstream in the transport path are opposite. It may be. That is, the upper side in the vertical direction of the transport path may be the upstream side of the transport, and the lower side in the vertical direction of the transport path may be the downstream side of the transport. As described above, even if the upstream and downstream positions of the transport path are different, the same effect as that of the above-described embodiment can be obtained.

Next, another embodiment of the drying apparatus according to the present invention will be described. FIG. 11 is a diagram showing an arrangement example of the heating rollers 19 according to the present embodiment. As shown in FIG. 11, two heating rollers 19 are arranged on one side of the horizontal folding position of the transport path of the recording medium 13. For example, the first roller 191 arranged in the uppermost stream and the second roller 192 arranged downstream and directly above the first roller 191 are each configured by using two heating rollers 19. In addition, one may be a transport roller which omits the heating means from the heating roller 19.

As in the present embodiment, the arrangement of the heating rollers 19 forming the transport path of the recording medium 13 inside the drying portion 5 allows wet air to be generated even if two heating rollers are arranged at the horizontal ends. It will be efficiently exhausted by the exhaust equipment without contacting the recording medium 13 and surrounding parts. This makes it possible to prevent the occurrence of dew condensation due to moist air.

Next, yet another embodiment of the drying apparatus according to the present invention will be described. FIG. 12 shows an example in which the heating rollers 19 are arranged diagonally instead of horizontally. As shown in FIG. 12, the heating roller 19 is arranged so as to transport the recording medium 13 while folding back the transport path. The lower part of FIG. 12 is the upstream side and the upper part is the downstream side, but this may be reversed. The vertical tangent line of the winding side side surface of the heating roller 19 arranged vertically below the drying portion 5 is horizontally outside the vertical tangent line of the winding side side surface of the heating roller 19 arranged vertically upward. Just do it.

Even if the arrangement of the heating rollers 19 forming the transport path of the recording medium 13 inside the drying portion 5 is slanted with respect to the horizontal direction as in the present embodiment, the moist air is still in contact with the recording medium 13 and surrounding parts. It will be efficiently exhausted by the exhaust equipment without contact. This makes it possible to prevent the occurrence of dew condensation due to moist air.

As described above, the drying device 1 in each embodiment forms a transport path around which the recording medium 13 is wound and heated and transported by combining a plurality of heating rollers 19. The recording medium is heated by being wound around the heating roller 19, and excess solvent and moisture remaining on the printing surface are evaporated and dried.

The transport path of the recording medium 13 is such that the winding side end face of the recording medium 13 in the heating roller 19 arranged at the same side position in the vertical direction from the upstream in the transport direction to the downstream in the transport direction is the heating roller 19 located upstream in the transport direction. It is set on the inner side in the vertical direction (opposite side to the winding side end surface) with respect to the winding side end surface of the recording medium 13.

As a result, when the steam generated downstream of the transport path moves upward, it is possible to prevent the steam from adhering to the heating roller 19 and the guide 22 mounted on the heating roller 19 and condensing. Further, since the moist air generated and rising by the heating roller 19 directly below does not directly hit the recording medium 13, dew condensation does not occur on the recording medium 13.

Further, according to the drying device 1 in each embodiment, the rib 23 in which the guide 22 is formed by sheet metal processing and the guide 22 provided with the ventilation hole 25 between the rib 23 and the rib 23 are provided on the outer peripheral portion of the heating roller 19. As a result, the moist air generated by the heat transfer from the heating roller 19 is efficiently exhausted upward.

Further, according to the drying device 1 in each embodiment, by forming the guide 22 by the wire-shaped member, the moist air generated by the heat transfer from the heating roller 19 is efficiently exhausted upward.

Further, according to the drying device 1 in the present embodiment, the interval changing mechanism (proximity separating mechanism 199) for changing the winding side end face position of the recording medium 13 in the heating roller 19 and the winding based on the preset changing conditions. By using the control means for changing the position of the end face on the hanging side, the heating rollers 19 can be changed to the optimum arrangement. Here, as the change conditions, the print area, the print density, the transport speed of the recording medium 13, the temperature of the heating roller 19, and the temperature and humidity in the chamber 6 can be used. Further, it is also possible to set the winding side end face position of each roller in an optimum arrangement by multiplying these plurality of conditions. As a result, the optimum arrangement of the heating rollers 19 can be set under various environmental conditions surrounding the recording medium 13 conveyed in the drying device 1. This makes it possible to prevent dew condensation of the solvent or water due to the temperature difference inside the drying device 1 and dew condensation of the solvent or water on the recording medium 13.

Further, according to the transport system 100 already described, the drying device 1 described above and a printing device 21 arranged in front of the drying device 1 and printed on the recording medium 13 and transported to the drying device 1 are provided. Therefore, the effects described above can be achieved.

Further, according to the drying method according to the present embodiment, the plurality of heating rollers 19 are arranged on the heating rollers 19 at the vertical positions in the vertical direction so that the side positions on the winding side do not overlap with each other. Even if the guide 22 and the recording medium 13 do not cause dew condensation even if the guide 22 and the recording medium 13 are heated and dried while being wound and conveyed, the recording medium 13 can be dried while being conveyed.

Further, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention, and all the technical matters included in the technical idea described in the claims are all. It is the subject of the present invention. Although the above-described embodiment shows a suitable example, those skilled in the art can realize various alternative examples, modified examples, modified examples, or improved examples from the contents disclosed in the present specification. These are included in the technical scope described in the appended claims.

1 Drying device 6 Chamber 13 Recording medium (object to be transported)
19 Heating roller 19a 1st heating roller 19b 2nd heating roller 19c 3rd heating roller 19d 4th heating roller 19e 5th heating roller 19f 6th heating roller 21 Printing device 22 Guide 30 Microcomputer unit 36 Interval control unit

JP-A-2007-187821

Claims (5)

A drying device in which a transport path for winding and heating and transporting a continuous object to be transported is formed by an array of rollers including at least one heating roller, and an exhaust means is provided above the transport path.
The transport path is formed by an array of rollers arranged at paired positions so as to direct the transported object from upstream to downstream while folding back the transported object to an appropriate length.
An interval changing mechanism for changing the horizontal interval of the rollers, which is arranged relative to a pair of positions where the transport path is folded back,
The basis weight of the object to be transported, the print area and print density to be printed on the object to be transported, the transfer speed of the object to be transported, the temperature of the heating roller, and the temperature and humidity in the chamber in which the heating roller is arranged. A control means for changing the relative spacing of the rollers based on any of the above,
The heating is arranged as the first roller, the second roller, the (n-1) roller, and the nth roller sequentially from the lower side in the vertical direction of the transport path, and is arranged mth from the lower side in the vertical direction of the transport path. When the roller is assumed to be the mth roller,
The first (m + 1) roller is characterized in that the distance from the pair of rollers is set so that the vertical tangent on the winding side of the object to be transported is located on the counter-winding side of the m-roller. Drying device.
However, m and n are integers, and n> m ≧ 1 and n ≧ 2. The vertical tangent on the winding side of the object to be transported in the m-roller has moved to the horizontal winding side with respect to the vertical tangent on the winding side of the object to be transported in the (m + 1) roller. The drying apparatus according to claim 1, wherein the position is used. Each of the rollers has a guide member on the outer peripheral portion, and has a guide member.
The drying apparatus according to claim 1 or 2, wherein the guide member is formed of a plate-shaped member having ventilation holes. Each of the rollers has a guide member on the outer peripheral portion, and has a guide member.
The drying apparatus according to claim 1 or 2, wherein the guide member is formed of a wire-shaped member. The drying apparatus according to any one of claims 1 to 4,
A transport system, which is arranged in front of the drying device, includes a printing device that prints on the object to be transported and transports the drying device to the drying device.