JP6284759B2 - Cold air cooling of printing paper - Google Patents

Description

  The present invention relates to an air cooling technique in which printing paper is dried with hot air and then cooled with cold air.

  In the web printing line, a printing machine, a hot air drying device, a roller cooling device, and a folding machine are arranged in sequence. In a printing machine, a strip-shaped paper is pulled out from a web and passed through a printing roller and printed with ink. The strip-shaped printing paper passes through the drying chamber of the hot air drying device and is heated with hot air, and the printing ink adhering to the paper surface is dried. The strip-shaped printing paper dried with hot air is cooled by sequentially passing through a plurality of cooling rollers of a roller cooling device. The strip-shaped printing paper cooled by contact with the cooling roller is folded by a folding machine and cut.

  The printed paper has a paper surface temperature of less than 100 ° C. when leaving the drying chamber of the hot air dryer, and near room temperature when leaving the roller cooling device. The roller cooling device cools the printing paper by the heat absorption of the cooling roller to bring the paper surface temperature close to room temperature.

  In the drying chamber of the hot air dryer, solvent vapor of the printing ink is generated by drying the printing ink. The printed paper exiting the drying chamber is directed to the roller cooling device with solvent vapor on the paper surface. The solvent vapor exiting the drying room with the printing paper is controlled to an amount that does not harm the health of the operator on the printing line.

JP-A-8-323959

[Task]
In the web-printing line as described above, the load of the roller cooling device that cools the belt-shaped printing paper to near room temperature after hot air drying of the printing ink is large. The roller cooling device wants to reduce the load as much as possible.

  Further, in the roller cooling device, if the printing paper solvent contacting the cooling roller is accompanied by the solvent vapor of the printing ink, the solvent vapor is cooled and tarized, and the printing paper and the cooling roller are soiled. It is desirable to reduce the solvent vapor accompanying the printing paper as much as possible before contacting the cooling roller.

[Idea]
After the strip-shaped printing paper exited the drying chamber of the hot air drying device and before contacting the cooling roller of the roller cooling device, it was decided to blow cold air on both sides of the paper. It was decided to provide a cold air cooling device that cools by blowing cold air. The printing paper is cooled by blowing cold air before being cooled by the roller cooling device. Further, the solvent vapor accompanying the printing paper is peeled off by blowing cold air before contacting the cooling roller of the roller cooling device.

  The printing paper exiting the drying chamber of the hot air drying device enters the roller cooling device in a state where the temperature is lowered by blowing cold air to reduce the accompanying amount of the solvent vapor. In the roller cooling device, the load decreases as the cooling start temperature of the printing paper decreases. In addition, the contamination of the printing paper and the cooling roller is reduced due to the decrease in the accompanying amount of the solvent vapor.

  Furthermore, the in-paper position of the printing paper on which the cold air is blown is made to coincide on both sides of the printing paper. The force for pressing one side of the printing paper by the blowing of cold air and the force for pressing the other side make the strength to maintain the thickness direction position of the printing paper. As a result, the thickness direction position of the printing paper is unlikely to fluctuate. It is hard to wave.

The specific configuration is as follows.
The cold air cooling device is provided with a cold air jet pipe between the drying chamber of the hot air drying device and the cooling roller of the roller cooling device. The cold air jet pipes are respectively arranged on the upper side and the lower side of the travel path of the printing paper. The upper cold air ejection pipe is provided with a jet outlet for blowing cold air onto the upper surface of the printing paper. The lower cold air ejection pipe is provided with an ejection port for blowing cold air onto the lower surface of the printing paper. The upper and lower cold air blowing pipes are connected to a cold air supply source for blowing unheated air.

  Further, the upper jet port and the lower jet port are positioned so as to face each other across the travel path of the printing paper. The cold air coming out from the upper jet outlet pushes the printing paper downward and the cold wind coming out from the lower jet outlet pushes the printing paper upward between the upper jet outlet and the lower jet outlet. Make it strong. Then, the vertical position of the printing paper can be maintained. The printing paper is difficult to move up and down. It is hard to wave.

  Furthermore, when the distance between the drying chamber of the hot air drying device and the cooling roller of the roller cooling device is long and the drooping between the printing papers becomes large, the cold air cooling device will dry the upper and lower jet outlets with hot air. It arrange | positions in the intermediate position between the drying chamber of an apparatus, and the cooling roller of a roller cooling device. As a result, it is possible to reduce the amount of printing paper hanging down.

  Moreover, the cold air cooling device arrange | positions the upper and lower jet nozzle in the position close | similar to the exit of a drying chamber. Then, the exit of a drying chamber will be in the state closed with the cold wind which blows off from the upper jet port, and the cold wind which blows off from the lower jet port. Hot air containing the printing ink solvent vapor in the drying chamber is less likely to leak from the outlet.

1 . In the printing line where the belt-shaped printing paper passes through the drying chamber of the hot air drying device and is heated with hot air, and then cooled by passing through the cooling roller of the roller cooling device,
A cold air cooling device that cools by blowing cold air is installed.
The cold air cooling device is provided with a cold air jet pipe between the drying chamber of the hot air drying device and the cooling roller of the roller cooling device,
The cold air jet pipes are respectively arranged on the upper side and the lower side of the travel path of the printing paper,
The upper cold air jet pipe is provided with a jet outlet for blowing cold air on the upper surface of the printing paper,
The lower cold air jet pipe is provided with a jet outlet that blows cold air on the lower paper surface of the printing paper,
The upper and lower cold air outlet pipes are connected to a cold air source that blows unheated air ,
The upper and lower jet outlets are arranged at an intermediate position between the drying chamber of the hot air drying device and the cooling roller of the roller cooling device, and are configured to reduce the amount of sag between the printing papers. Cold air cooling device for printing paper.
2. In the cold air cooling device for printing paper of 1 above,
The upper jet port and the lower jet port are positioned to face each other across the travel path of the printing paper,
The cold air coming out from the upper jet outlet pushes the printing paper downward and the cold wind coming out from the lower jet outlet pushes the printing paper upward between the upper jet outlet and the lower jet outlet. It is characterized by having a structure for maintaining the strength and having a function of maintaining the vertical position of the printing paper.
3. In the printing line where the belt-shaped printing paper passes through the drying chamber of the hot air drying device and is heated with hot air, and then cooled by passing through the cooling roller of the roller cooling device,
A cold air cooling device that cools by blowing cold air is installed.
The cold air cooling device is provided with a cold air jet pipe between the drying chamber of the hot air drying device and the cooling roller of the roller cooling device,
The cold air jet pipes are respectively arranged on the upper side and the lower side of the travel path of the printing paper,
The upper cold air jet pipe is provided with a jet outlet for blowing cold air on the upper surface of the printing paper,
The lower cold air jet pipe is provided with a jet outlet that blows cold air on the lower paper surface of the printing paper,
The upper and lower cold air outlet pipes are connected to a cold air source that blows unheated air ,
The upper and lower jet outlets are located close to the outlet of the drying chamber, and the outlet of the drying chamber is closed with cold air blown from the upper jet outlet and cold air blown from the lower jet outlet. A cold air cooling device for printing paper.
4). In the cold air cooling device for printing paper of 3 above,
The upper jet port and the lower jet port are positioned to face each other across the travel path of the printing paper,
The cold air coming out from the upper jet outlet pushes the printing paper downward and the cold wind coming out from the lower jet outlet pushes the printing paper upward between the upper jet outlet and the lower jet outlet. It is characterized by having a structure for maintaining the strength and having a function of maintaining the vertical position of the printing paper .

  The printing paper exiting the drying chamber of the hot air dryer enters the roller cooling device in a state where the temperature is lowered by blowing cold air to reduce the accompanying amount of the solvent vapor of the printing ink. In the roller cooling device, the load decreases as the cooling start temperature of the printing paper decreases. In addition, the contamination of the printing paper and the cooling roller is reduced due to the decrease in the accompanying amount of the solvent vapor.

The side view of the cold air cooling device of the printing paper in the 1st example of the embodiment of the present invention. The AA arrow directional view of FIG. The side view of the cold air cooling device of the printing paper in the 2nd example of an embodiment. The BB line arrow directional view of FIG.

[First example (see FIGS. 1 and 2)]
In the printing line, as shown in FIG. 1, the strip-shaped printing paper P that has passed through the printing machine passes through the drying chamber 1 of the hot air drying device and is heated with hot air, passes through the cold air cooling device 11, and blows cold air. Then, the temperature is lowered to reduce the accompanying amount of the printing ink solvent vapor, and the paper passes through a plurality of cooling rollers of the roller cooling device 21 to be cooled, and reaches the folding machine 9.

  As shown in FIGS. 1 and 2, the cold air cooling device 11 of the present example includes two pieces at an intermediate position between the outlet 2 of the drying chamber 1 of the hot air drying device and the first cooling roller 22 of the roller cooling device 21. Cold air jet pipes 12 and 13 are provided. The two cold air jet pipes 12 and 13 are fixed to the upper end of the stand 14 at the ends, and are arranged horizontally along the width direction of the printing paper P on the upper and lower sides of the travel path of the printing paper P. Yes.

  The upper cold air jet pipe 12 is provided with a downward jet port 15 for blowing cold air onto the upper surface of the printing paper P. The lower cold air jet pipe 13 is provided with an upward jet 16 for blowing cold air onto the lower paper surface of the printing paper P. The upper and lower cold air ejection pipes 12 and 13 are connected to the cold air supply sources 18 and 19 via the air blowing pipe 17. The cold air supply source is configured to cool external air with the cooler 18 and blow with the blower 19.

  The upper downward jet port 15 and the lower upward jet port 16 are elongated along the width direction of the printing paper P and have the same shape and size. And it arrange | positions in the position which adjoins across the travel path of the printing paper P, and opposes across the travel path of the printing paper P. The cold air blown from the upper downward jet port 15 pushes the printing paper P downward and the cold wind blown from the lower upward jet port 16 pushes the printing paper P upward causes the printing paper P to blow upward. 15 and the lower jet port 16 are made strong.

  Further, the upper jet port 15 and the lower jet port 16 are formed as horizontally long rectangular slits that cross the travel path of the printing paper P, and are longer than the width of the printing paper P. The configuration is such that cold air is blown over the entire width of the printing paper P.

  The roller cooling device 21 has a plurality of cooling rollers arranged in parallel along the width direction of the printing paper P. The first cooling roller 22 has an upper end at which the printing paper P first comes into contact with the printing paper P that exits from the outlet 2 of the drying chamber 1. The travel path of the printing paper P is horizontal between the outlet 2 of the drying chamber 1 and the upper end of the first cooling roller 22.

  The roller cooling device 21 is provided with water cooling devices 25 and 26 for cooling the cooling rollers 22, 23 and 24 from the inside. The water cooling device is a cooling water circulation type, cooling water returned from the cooling roller is cooled by the cooler 25, pushed out by the pump 26, and supplied to the cooling roller. The cooling water enters one end of the third cooling roller 24 from the pump 26, exits from the other end of the third cooling roller 24, enters one end of the second cooling roller 23, and exits from the other end of the second cooling roller 23. It enters one end of the first cooling roller 22, exits from the other end of the first cooling roller 22, and returns to the cooler 25.

An experimental example of normal operation for operating the cold air cooling device 11 is as follows.
The paper surface temperature of the printing paper P becomes 97 ° C. at the first measurement point 41 immediately after the printing paper P exits the outlet 2 of the drying chamber, passes through the cold air cooling device 11 and immediately enters the roller cooling device 21. 81 ° C. at 2 measurement points 42, 34 ° C. at the third measurement point 43 immediately after passing through the third cooling roller 24 of the roller cooling device 21, and 4th measurement point immediately before leaving the roller cooling device 21 and entering the folding machine 9. It becomes 27 degreeC in 44. In the roller cooling device 21, the cooling start temperature of the printing paper P becomes 81 ° C. The cooling water circulating through the third cooling roller 24, the second cooling roller 23, the first cooling roller 22, and the water cooling devices 25, 26 has a flow rate of 220 L / min and a temperature of 24 ° C. when pumped by the pump 26. When returning to the cooler 25, the flow rate is the same and the temperature is 26 ° C. The circulating cooling water of the roller cooling device 21 absorbs the heat of the printing paper P and the temperature rises by 2 ° C.

The comparative example for this experimental operation example and the operation example in which the cold air cooling device 11 is not operated have the following conditions.
The cold air cooling device 11 stops the operation of the cold air supply sources 18 and 19. The paper surface temperature of the printing paper P is set to the same 97 ° C. and 27 ° C. at the first measuring point 41 immediately after the printing paper P exits the drying chamber outlet 2 and the fourth measuring point 44 just before entering the folding machine 9. The circulating cooling water of the roller cooling device 21 is set to the same flow rate of 220 L / min, and the temperature when pumped by the pump 26 is set to the same 24 ° C.

The result of this comparative operation example is as follows.
The paper surface temperature of the printing paper P is 89 ° C. at the second measurement point 42 immediately before the printing paper P enters the roller cooling device 21, and the same 34 ° C. at the third measurement point 43. In the roller cooling device 21, the cooling start temperature of the printing paper P is 8 ° C. higher than that when the cold air cooling device 11 is operated. The circulating cooling water has a temperature of 26.4 ° C. when it returns to the cooler 25. The heat of the printing paper P is absorbed and the temperature rises by 2.4 ° C. The temperature of the circulating cooling water when it returns to the cooler 25 is 0.4 ° C. higher than when the cold air cooling device 11 is operated. The cooling load of the cooler 25 increases.
Eventually, during the operation of the cold air cooling device 11, the roller cooling device 21 decreases the cooling start temperature of the printing paper P and the cooling load.

  The cold air cooling device 11 of this example is a cold air blown on both sides of the printing paper P, and the jetting ports 15 and 16 of the printing paper P are arranged in the thickness direction position and the vertical position at the upper and lower jetting ports 15. , Maintain between 16. There is a holding function of the printing paper P. Therefore, when the distance between the outlet 2 of the drying chamber and the first cooling roller 22 of the roller cooling device is long and the sag of the printing paper P increases, the upper side is positioned at the position where the sag is maximum. Lower jets 15 and 16 are arranged. Then, the amount of sag of the printing paper P between them can be reduced.

[Second example (see FIGS. 3 and 4)]
As shown in FIGS. 3 and 4, the cold air cooling device 11 of this example has upper and lower cold air ejection pipes 12 and 13 attached to the wall 3 on the outlet side of the drying chamber 1. The stand 14 in the first example is unnecessary.

  The wall 3 on the outlet side of the drying chamber 1 penetrates the horizontally long rectangular outlet 2, and the upper cold air outlet pipe 12 and the lower cold air outlet pipe 13 are provided at the outlet 2 at the upper and lower positions, respectively. Arranged along.

  Immediately after exiting the outlet 2 of the drying chamber, the printing paper P is blown with cold air from the downward jet outlet 15 of the upper cold air jet pipe 12 to the upper paper surface, and the lower cold air jet is ejected to the lower paper surface. Cold air is blown from an upward jet 16 of the pipe 13. As in the first example, the printing paper P exiting the drying chamber 1 enters the roller cooling device 21 in a state where the temperature of the printing paper P is lowered by blowing cold air to reduce the accompanying amount of the printing ink solvent vapor.

The upper and lower jet outlets 15 and 16 are arranged at positions close to the outlet 2 of the drying chamber 1. The outlet 2 of the drying chamber 1 is closed by a cool air curtain that blows out from the upper slit-shaped jet port 15 and a cold wind curtain that blows out from the lower slit-shaped jet port 16. As a result, the hot air containing the printing ink solvent vapor in the drying chamber 1 is difficult to leak out from the outlet 2.
Other points are the same as in the first example. Parts similar to those in the first example are denoted by the same reference numerals as those in the first example.

[Modification]
The present invention is not limited to the above embodiment. The following modifications are exemplified.
1. In the above embodiment, in the cold air cooling device 11, the cold air supplied to the upper and lower cold air jet pipes 12 and 13 is set to a temperature lower than room temperature by the cooler 18, but it is room temperature air.
2. In the above embodiment, the upper and lower jet outlets 15 and 16 are formed as a single elongated long hole, but a plurality of small holes are arranged in a line.
3. In the first example of the above embodiment, the cold air jet pipes 12 and 13 are supported by the stand 14 in a cantilevered manner, but support both ends.

P Printing paper 1 Drying chamber 2 of the hot air drying device 2 Exit 3 of the drying chamber Wall 9 on the exit side of the drying chamber Folding machine 11 Cooling air cooling devices 12, 13 Cooling air jet tube 12 Upper cold air jet tube 13 Lower cold air jet tube 14 Stand 15 Upper downward jet 16 Lower upward jet 17 Blower pipes 18, 19 Cold air supply source 18 Cooler 19 Blower 21 Roller cooling device 22 First cooling roller 23 Second cooling roller 24 Third cooling roller 25 , 26 Water cooling device 25 Cooler 26 Pump 41 First measurement point 42 immediately after the printing paper exits the drying chamber outlet Second measurement point 43 immediately before entering the roller cooling device Third measurement immediately after passing the third cooling roller Point 44 Fourth measurement point just before leaving the roller cooling device and entering the folding machine

Claims (4)

In the printing line where the belt-shaped printing paper passes through the drying chamber of the hot air drying device and is heated with hot air, and then cooled by passing through the cooling roller of the roller cooling device,
A cold air cooling device that cools by blowing cold air is installed.
The cold air cooling device is provided with a cold air jet pipe between the drying chamber of the hot air drying device and the cooling roller of the roller cooling device,
The cold air jet pipes are respectively arranged on the upper side and the lower side of the travel path of the printing paper,
The upper cold air jet pipe is provided with a jet outlet for blowing cold air on the upper surface of the printing paper,
The lower cold air jet pipe is provided with a jet outlet that blows cold air on the lower paper surface of the printing paper,
The upper and lower cold air outlet pipes are connected to a cold air source that blows unheated air ,
The upper and lower jet outlets are arranged at an intermediate position between the drying chamber of the hot air drying device and the cooling roller of the roller cooling device, and are configured to reduce the amount of sag between the printing papers. Cold air cooling device for printing paper. The upper jet port and the lower jet port are positioned to face each other across the travel path of the printing paper,
The cold air coming out from the upper jet outlet pushes the printing paper downward and the cold wind coming out from the lower jet outlet pushes the printing paper upward between the upper jet outlet and the lower jet outlet. The cold air cooling device for printing paper according to claim 1 , wherein the printing paper has a function of maintaining strength and maintains a vertical position of the printing paper. In the printing line where the belt-shaped printing paper passes through the drying chamber of the hot air drying device and is heated with hot air, and then cooled by passing through the cooling roller of the roller cooling device,
A cold air cooling device that cools by blowing cold air is installed.
The cold air cooling device is provided with a cold air jet pipe between the drying chamber of the hot air drying device and the cooling roller of the roller cooling device,
The cold air jet pipes are respectively arranged on the upper side and the lower side of the travel path of the printing paper,
The upper cold air jet pipe is provided with a jet outlet for blowing cold air on the upper surface of the printing paper,
The lower cold air jet pipe is provided with a jet outlet that blows cold air on the lower paper surface of the printing paper,
The upper and lower cold air outlet pipes are connected to a cold air source that blows unheated air ,
The upper and lower jet outlets are located close to the outlet of the drying chamber, and the outlet of the drying chamber is closed with cold air blown from the upper jet outlet and cold air blown from the lower jet outlet. A cold air cooling device for printing paper. The upper jet port and the lower jet port are positioned to face each other across the travel path of the printing paper,
The cold air coming out from the upper jet outlet pushes the printing paper downward and the cold wind coming out from the lower jet outlet pushes the printing paper upward between the upper jet outlet and the lower jet outlet. 4. The cold air cooling device for printing paper according to claim 3 , wherein the printing paper has a function of maintaining strength and has a function of maintaining the vertical position of the printing paper.

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