JP2008070108A - Method for operating drying device of printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for operating a drying device of a printer for operating a heat radiation device by predetermined outputs of the heat radiation device and operating a hot air device by outputs of hot air for realizing predetermined flow rate of supply air volume, predetermined flow rate of exhaust air volume, and predetermined air temperature. <P>SOLUTION: This drying device is operated for drying purpose while the heat radiation device reduces its outputs after a failure or interruption occurs during a first duration time or is stopped when the failure or interruption occurs during printing operation. The hot air device is operated while operation parameters remain unchanged, and then, if the failure or interruption cannot be corrected during the first duration time, the hot air device is operated by outputs of hot air for reducing air temperature while the flow rate of supply air volume and the flow rate of exhaust air volume are reduced during a second duration time following the first duration time. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The invention relates to a method for operating a drying device of a printing press according to claim 1 or 9.

  In a sheet printing machine, printing sheets are moved one after another so as to pass through a plurality of printing devices or varnishing devices provided continuously in front and rear. At this time, the partial image portion is applied using printing ink in each printing device, or the partial image portion is applied using varnish in each varnishing device. By printing a plurality of such partial image line portions in an overlapping manner, a desired print image line portion is finally realized on the printed sheet.

  In addition to the printing apparatus or the varnishing apparatus as described above, a sheet-fed printing press provided with at least one drying apparatus is known from the business site. With such a drying device, the printed sheets can be dried, so that, for example, when printed printed sheets are discharged from the sheet press and sorted while forming a discharge pile, Adhesion is avoided. Furthermore, it is known that the printing sheet is dried by a drying device between the steps of applying the partial image portion made of varnish. As a result, it is possible to perform overprinting with a high quality of the partial image portion made of varnish.

  Known dryers for sheet processing machines are usually equipped with a heat dissipation device and a hot air device, where the heat radiation can be applied to the printed sheet of paper and the temperature is adjusted by the hot air device. A stream of air can be applied to the printed sheet. The present invention relates to a method for operating a drying device of a printing press.

  A printing machine having a drying device is known from Patent Document 1, in which the drying device is operated using a control unit. The control unit is supplied with at least one signal having a value characterizing the printing process, so that the control unit generates a signal, which changes the operation of the drying apparatus.

Patent Document 2 relates to an operation method of a printing press having a drying device. In this method, in the printing press, the printing operation is started only after the drying device has achieved the optimum operating conditions. The optimum operating conditions of the drying apparatus are determined in particular according to the ambient temperature, the ink and varnish or their layer thicknesses and possibly further parameters.
EP 1144271 German Patent Invention No. 4303266

  In view of the above circumstances, an object of the present invention is to realize a novel method for operating a drying device of a printing press.

  The above problem is solved by the method of claim 1 according to a first aspect of the present invention. According to this method, when a failure or interruption occurs during a printing operation, the heat dissipation device operates with a reduced output of the heat dissipation device during a first duration after such failure or interruption occurs. The hot air device is operated without changing the operation parameter. And when the failure or interruption is not resolved during the first duration, the hot air device reduces the supply volume flow rate and the exhaust volume flow rate during the second duration following the first duration. In such a state, the engine is operated with hot air output that causes a drop in air temperature.

  Said object is solved by a method according to claim 9 according to a second aspect of the present invention. According to this method, the drying device is heated before the start of the printing operation after the printing press is started or after a relatively long-lasting failure or interruption of the printing operation is resolved. That is, when the heat dissipating device is stopped, the hot air device has the maximum hot air output until the air temperature reaches a predetermined value, but the exhaust air volume flow rate is smaller than the printing operation and the exhaust gas is less than the printing operation. Operated with volumetric flow rate.

  Further preferred forms of the invention are set out in the dependent claims and in the following detailed description. Embodiments of the present invention will be described below in detail with reference to the drawings, but the present invention is not limited to these embodiments. The drawings show the following.

  The present invention relates to a method for operating a drying device of a printing press, in particular a sheet-fed printing press, having a plurality of printing devices and / or varnishing devices.

  The drying device to be operated by the method according to the present invention comprises at least one heat radiating device and at least one hot air device, and can radiate heat radiation on the printed sheet by the heat radiating device, and can be printed by the hot air device. A temperature-controlled air stream can be applied to the sheet. At this time, the heat radiating device and the hot air device are provided side by side when viewed in the transport direction of the printed sheet.

  In the normal operation of the printing press, that is, in the normal drying operation of the drying device, the heat radiating device of the drying device is operated with a predetermined heat radiating device output.

  In the normal printing operation of the printing press and along with the normal drying operation of the drying device, the hot air device outputs a hot air output that realizes a predetermined air supply volume flow rate, a predetermined exhaust volume flow rate, and a predetermined air temperature. Driven by.

  The present invention relates to the details of the operation of the drying device, so that the optimum drying of the printed sheet can be realized during the printing operation or at the start of the printing operation, and printing of printing waste paper can be prevented. The drying device is operated.

  In the signal flowchart shown in FIG. 1, the normal printing operation of the printing press and the normal drying operation of the drying apparatus are represented by step 10. In the normal printing operation and the normal drying operation shown in the figure, the heat radiating device is operated with a predetermined heat radiating device output, and the hot air device has a predetermined air supply volume flow rate, a predetermined exhaust volume flow rate, and a predetermined air temperature. Is driven by hot air output.

  Step 11 continuously checks whether a fault or interruption of the printing operation occurs during a normal printing operation. At this time, if it is confirmed that no failure or interruption of the printing operation has occurred, the process 10 is repeatedly controlled. On the other hand, if it is confirmed in step 10 that a failure or interruption of the printing operation has occurred, branch control is performed on step 12.

  Immediately after a failure or interruption of the printing operation occurs in step 12, the heat dissipation device is operated in a state where the output of the heat dissipation device is reduced. In particular, immediately after a failure or interruption of the printing operation occurs, the heat dissipation device is stopped. The operating parameters of the hot air device remain unchanged for the time being.

  In step 13 following step 12, it is checked whether the failure or the interruption of the printing operation has been resolved. At this time, when it is confirmed that the failure or the interruption of the printing operation has been eliminated, the repeated control is performed from the step 13 to the step 10, and the printing operation and the drying operation are resumed. Upon resumption of operation, the heat radiating device is operated at the heat radiating device output set for the normal printing operation and simultaneously with the normal drying operation.

  On the other hand, if it is confirmed in step 13 that the failure or interruption of the printing operation has not been resolved, the duration after the occurrence of the failure or interruption of the printing operation in step 14 is set to the first time set in advance. Inspected for less than duration. If the duration after the occurrence of the failure or interruption of the printing operation is less than the preset first duration, the iterative control is performed from step 14 to step 13. On the other hand, when it is confirmed that the duration after the occurrence of the failure or the interruption of the printing operation in step 14 exceeds the preset first duration, the steps 14 to 15 are performed. Branch control is performed.

  Immediately after the first duration has elapsed in step 15, the hot air device of the drying device is operated with hot air output that causes a decrease in air temperature, with the supply volume flow rate and the exhaust volume flow rate reduced. The At this time, the heat dissipation device continues to be stopped. The reduced air temperature to be realized in step 15 is 80% of the air temperature set for normal printing operation in particular, but this value of 80% is purely typical and the method And any other value depending on the configuration.

  Thus, when the failure or interruption of the printing operation is not resolved within the first duration and the printing operation is not resumed, the hot air output of the hot air device is reduced, and thereby the configuration of the printing machine or drying device to which the hot air hits. The members are not damaged.

  In step 16 following step 15, it is checked whether the failure or interruption of the printing operation has been resolved after the first duration has elapsed. If the failure or the interruption of the printing operation has been resolved after the first duration has elapsed, iterative control is performed from step 16 to step 10. That is, the printing operation of the printing press and the drying operation of the drying device are restarted.At this time, the hot air device of the drying device is set to the normal printing operation or the normal drying operation, and the supply air volume flow rate is set. The exhaust volume flow rate set for the printing operation and the drying operation and the hot air output that generates the air temperature set for the printing operation and the drying operation are operated.

  On the other hand, if it is confirmed in step 16 that the failure or interruption of the printing operation has not been resolved, branch control is performed for step 17. At this time, in step 17, it is checked whether a second duration following the first duration has been exceeded. If it is determined in step 17 that the second duration has not yet been exceeded, then iterative control is performed on step 16. On the other hand, it was confirmed that the second duration was exceeded in step 17, that is, the failure or the interruption of the printing operation was not resolved within the first duration or the second duration. Then, branch control is performed for the step 18.

  Subsequently, in step 18, the drying apparatus is shifted to the standby mode. In this standby mode, the heat radiating device is stopped, and the hot air device is operated with a minimized hot air output.

  After the drying device has been transferred to the standby mode in step 18, it is checked in step 19 whether the failure or interruption of the printing operation has been resolved in the standby mode. At this time, if it is confirmed that the failure has not been resolved, branch control is performed for step 19. On the other hand, in step 19, when it is confirmed that the failure or the interruption of the printing operation has been eliminated in the standby mode, branch control is performed from step 19 to step 20, and the drying apparatus is preheated. Is called.

  During the preheating of the drying device in step 20, the hot air device is at a maximum hot air output until the air temperature reaches the set value with the heat dissipation device stopped, except for the normal printing operation of the printing machine and At the same time, it is operated with a small supply volume flow rate and an exhaust volume flow rate compared to the normal drying operation of the drying apparatus. It is not until the air temperature reaches such a set value in step 20 that repetitive control is performed on step 10, and the normal printing operation and the normal drying operation are resumed.

  Such an air temperature setpoint to be reached during preheating in step 20 is in particular 80% of the air temperature set for normal printing operations, but this value of 80% is purely typical. Any other value is possible depending on the method and configuration.

  At the same time as the normal printing operation and the start of the normal drying operation, the hot air device has a supply volume flow rate set for the normal printing operation and an exhaust volume flow rate set for the normal printing operation. The operation is performed with the hot air output that realizes the air temperature set for the normal printing operation.

  Thereafter, the heat radiating device of the drying device is similarly operated with the heat output set for the normal printing operation.

  In this way, the method shown in FIG. 1 is distinguished into three stages when a failure or a printing operation is interrupted. The first stage immediately after the interruption or failure occurs is defined by the first duration, during which only the operating parameters of the heat dissipation device are adjusted and the operating parameters of the hot air device remain unchanged. is there. When the printing operation is not resumed in this first stage, the operating parameters of the hot air device are adjusted in the second stage defined by the second duration, thereby reducing the supply volume flow rate and the exhaust volume flow rate. In this state, a decrease in the air temperature is realized, and the decreased temperature particularly corresponds to 80% of the air temperature in a normal printing operation.

  When the printing operation is not resumed in this second duration and at the same time in the second stage, the third stage follows, in which the hot air device is operated in standby mode. The printer is cooled in the standby mode, but when the printing operation failure or the interruption of the printing operation is resolved in the standby mode, it is necessary to preheat the printing machine or the drying device before starting the printing operation. To be done. In the preheating, the hot air device is operated with the supply volume flow rate and the exhaust volume flow rate decreased, whereby the air temperature reaches a set value, and this set value is especially in normal printing operation or drying operation. It corresponds to 80% of the air temperature of hot air. This value of 80% is purely typical and can take any other value depending on the method and configuration.

  The above preheating action of the method according to the invention is not carried out only when the printing operation is resumed from the standby mode. Such preheating is also performed when the printing press is newly started.

  The method according to the invention effectively avoids printing of printing waste paper at the start-up of the printing press and after a relatively long fault or printing operation interruption has been resolved. Avoiding printing of printing waste paper is realized by performing preliminary overheating of the printer or the drying device before the start of the original printing operation. Furthermore, when printing operation is interrupted or failure occurs, the operation parameters of the drying device are continuously adjusted, and when a short failure occurs, the printing operation can be resumed immediately, while when a long failure occurs, the printing machine or drying device Overheating is avoided. Energy can be saved by the method according to the invention.

It is a signal flowchart for demonstrating the method of operating the drying apparatus of the printing press which concerns on this invention.

Explanation of symbols

10 processes 11 processes 12 processes 13 processes 14 processes 15 processes 16 processes 17 processes 18 processes 19 processes 20 processes

Claims (10)

A method of operating a drying device of a printing press,
The drying device has at least one heat dissipating device, whereby heat radiation is applied to the printed sheet, and the drying device has at least one hot air device, whereby the temperature-controlled air flow is applied to the printing sheet. In the printing operation of the printing press and the drying operation of the drying device together with the paper sheet,
The heat dissipating device is operated with a predetermined heat dissipating device output, and the hot air device is operated with a hot air output realizing a predetermined air supply volume flow rate, a predetermined exhaust volume flow rate, and a predetermined air temperature.
When a failure or interruption occurs during the printing operation,
After the failure or the interruption occurs in a first duration, the heat dissipation device is operated or stopped with a reduced heat dissipation device output,
The hot air device is operated with the operating parameters unchanged,
Thereafter, when the failure or interruption is not resolved in the first duration, the hot air device calculates a supply volume flow rate and an exhaust volume flow rate during a second duration following the first duration. An operation method of a drying apparatus, wherein the operation is performed by hot air output that realizes a decrease in air temperature in a reduced state.   In the second duration, the hot air output is controlled so that the air temperature is reduced compared to the printing operation and the drying operation together with the reduced supply air volume flow rate and exhaust volume flow rate. The operation method of the drying apparatus according to claim 1, wherein the value obtained is a measured value.   When the failure or interruption is resolved within the first duration and the printing operation and the drying operation are resumed, the heat dissipation device is set for the printing operation and the drying operation. The operation method of the drying apparatus according to claim 1, wherein the operation is performed with the output of the heat radiating device.   When the fault or the interruption is resolved within the second duration and the printing operation and the drying operation are resumed, the hot air device is set for the printing operation and the drying operation. The air supply volume flow rate, the exhaust volume flow rate set for the printing operation and the drying operation, and the air temperature set for the printing operation and the drying operation are set. The operation method of the drying apparatus according to any one of claims 1 to 3, wherein the operation is performed with a hot air output to be realized.   The operation of the drying device according to any one of claims 1 to 4, wherein the heat dissipation device is further operated with a heat dissipation device output set for the printing operation and the drying operation. Method.   The operation of the drying device according to any one of claims 1 to 5, wherein when the failure or the interruption is not resolved within the second duration, the hot air device is shifted to a standby mode. Method.   When the failure or the interruption is resolved in the standby mode, the hot air device reduces the supply volume flow rate and the exhaust volume flow rate at the maximum hot air output until the air temperature reaches a set value. The operation method of the drying apparatus according to claim 6, wherein the operation is performed in a wet state.   When the air temperature reaches the set value, the printing operation and the drying operation are resumed, and the hot air device sets the supply volume flow rate set for the printing operation and the drying operation. And the exhaust volume flow rate set for the printing operation and the drying operation, and the hot air output for realizing the air temperature set for the printing operation and the drying operation. The operation method of the drying apparatus according to claim 7, wherein the heat dissipation device is operated with the heat dissipation device output set for the printing operation and the drying operation. A method of operating a drying device of a printing press,
The drying device has at least one heat dissipating device, whereby heat radiation is applied to the printed sheet, and the drying device has at least one hot air device, whereby the temperature-controlled air flow is applied to the printing sheet. In the method of hitting the paper,
After the start-up of the printing press or after a relatively long failure or printing operation interruption has been resolved, the drying device is heated before the start of the printing operation, the heating being in a state where the heat dissipation device is stopped, The hot air device has the maximum hot air output until the air temperature reaches a set value, but the supply air volume flow rate is reduced compared to the printing operation and the exhaust volume flow rate is reduced compared to the printing operation. A drying apparatus operating method, wherein the drying apparatus is operated in a state.   When the air temperature reaches the set value, the printing operation is started, and the hot air device supplies the air supply volume flow rate set for the printing operation and the drying operation, and the printing operation and the same. And the exhaust volume flow rate set for the drying operation, and the printing operation and the hot air output that realizes the air temperature set for the drying operation. The operation method of the drying apparatus according to claim 9, wherein the operation is performed with a heat dissipation device output set for the drying operation.

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