Abstract:
A color system of a rotary printing press includes a doctor blade device with a doctor blade chamber containing ink for a printing process, an ink reservoir from which ink is supplied to the doctor blade chamber, and a supply system which allows ink to be supplied inside the color system. The color system is connected to a storage reservoir into which ink from the color system is introduced, to a solvent reservoir containing solvent for cleaning the color system, and to a refuse container into which ink soiled by the solvent is introduced. The supply system cleans the color system by automatically pumping off ink to the storage reservoir, and automatically cleaning with the solvent, by collecting the ink in the ink reservoir and supplying the solvent to the refuse container.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a U.S. national stage application of PCT/EP13/055874. 
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The invention relates to a method for cleaning a color system of a rotary printing press as well as a color system for a rotary printing press. 
     2. Description of the Prior Art 
     A method is described in U.S. Pat. No. 5,402,724 which, upon conclusion of the print job of a rotary printing press, cleans the doctor device, particularly its ink reservoir, from any and all ink residue. It is disadvantageous here that essential supply line and drainage line of the above-mentioned device are not considered in this cleaning process, so that ink residue remains uncleansed within the device in all areas. 
     DE 195 48 535 A1 discusses this problem and attains it such that the solvent is conveyed from the solvent container into the doctor device and simultaneously the drainage lines and supply lines are rinsed with said solvent. Additionally, a refuse container is provided which then can accept the solvent soiled with ink. 
     SUMMARY OF THE INVENTION 
     The objective of the present invention is attained through all the features thereof described herein. Other embodiments of the invention are also described herein. 
     The objective of the present invention is attained in all features of claim  1 . The dependent claims describe potential embodiments. Furthermore, the above-mentioned objective is attained in all features of the independent claim  12 . The dependent device claims describe potential embodiments. 
     According to the invention, a method is provided for cleaning a color system of a rotary printing press, with the color system comprising a doctor device with a doctor chamber, containing the ink for the printing process of a rotary printing press, an ink reservoir from which ink can be conveyed into the doctor chamber, and a conveyance system, which allows the conveyance of ink within the color system. Here, according to the invention the color system is connected to a storage container, into which ink from the color system can be introduced, a solvent container, in which the solvent is located for cleaning the color system, as well as a refuse container, into which the solvent soiled with ink can be introduced. Further, the conveyance system is embodied such that the following processing steps are performed for cleaning the color system:
     A: automatically pumping the ink off the color system via the conveyance system into the storage container;   B: automatically cleaning the color system via the solvent, with in a first cleaning step the solvent being collected in the ink reservoir, and in a second cleaning step the solvent being conveyed into the refuse container.   

     An essential advantage of the invention is the fact that, for example, in the event of a printing job being concluded or the color of the ink being changed, initially an automatic process of pumping the ink out of the color system occurs, with the ink being pumped into a separate storage container. This means that the ink is conveyed from the doctor device, particularly from the doctor chamber, into the storage container. Simultaneously a conveyance occurs or a process of pumping the ink out of the ink reservoir via the conveyance system into the storage container. The ink, which is present in the conveyance system, is also pumped into the storage container. After the step of pumping off, e.g. the storage container with the ink pumped out of the color system can be dissolved by the color system for storage purposes and stored at a different location. After the ink has been removed from the color system an automatic cleaning of the color system occurs, because always some ink residue remains within the color system, particular in the doctor chamber, the ink reservoir, as well as within the conveyance system. In this context, in the first cleaning step it occurs that the solvent is first pumped out of the solvent container via the conveyance system into the doctor chamber. In this first cleaning step another conveyance occurs of the solvent from the doctor chamber into the ink reservoir. After a defined period of time and/or after a defined volume flow of the solvent, which is conveyed by the conveyance system via the doctor chamber into the ink reservoir, this first cleaning step is concluded. The solvent is therefore collected in the ink reservoir, with simultaneously the ink reservoir also being cleaned by the collection of the solvent in the ink reservoir. Subsequently, in the second cleaning step the solvent is pumped off and/or removed, which is present in the ink reservoir and is already soiled and/or enriched with ink, into the refuse container connected to the conveyance system, with the conveyance system being switched such that the solvent already enriched with ink is conveyed by the conveyance system in the direction towards the refuse container, however this solvent cannot flow into the doctor chamber of the doctor device. This serves the purpose that the doctor chamber, already cleaned by the clean solvent, is not unnecessary soiled again by the solvent enriched with ink. Subsequently, the color system which has come into contact with the solvent enriched with ink is rinsed with clean solvent (in the direction towards the refuse container). 
     It is particularly advantageous that both processing steps, thus the process of pumping the ink off the storage container and the cleaning of the color system via solvent, are performed automatically. Thus, no operating personnel is required manually initiating and/or ending the processing step of pumping off the ink and/or the processing step of cleaning the color system via the solvent. 
     Advantageously, in the first cleaning step the doctor chamber, the ink reservoir, and at least partially the conveyance system can be cleaned. An almost complete cleaning of the color system can be achieved by the conveyance system according to the invention as well as the method according to the invention, with in addition to the doctor chamber and the conveyance system here the ink reservoir can also be cleaned, which in the first cleaning step serves as the collection container for the solvent. After the solvent has been conveyed out of the ink reservoir into the refuse container, new ink can flow into the cleaned ink reservoir, which can be used e.g., for the new upcoming printing job. 
     Further, it is possible that the conveyance system for the doctor chamber comprises a primary supply line and a primary drainage line, with the primary supply line comprising a flow pump and the primary drainage line comprising a return flow pump, with particularly a bypass line being arranged between the doctor chamber and the pumps. At its pressure side, the flow pump comprises a supply line towards the doctor chamber, with this supply line being the primary supply line, which extends between the ink reservoir and the doctor chamber. Another supply line is provided at the suction side of the flow pump, which connects the ink reservoir to the flow pump. Advantageously, the supply line may show a valve at the suction side of the flow pump, which is switched between the flow pump and the ink reservoir. The supply line at the pressure side of the flow pump may also be equipped with a valve, which is switched between the doctor chamber and the flow pump. 
     Additionally, it is possible that the primary drainage line comprises a drainage line, which is arranged at the suction side of the return flow pump. This drainage line may show a valve between the return flow pump and the doctor chamber. Additionally, the primary drainage line may comprise another drainage line at the pressure side of the return flow pump, with the latter drainage line perhaps showing a valve between the ink reservoir and the return flow pump. Thus, it is possible that a circuit can be provided, so that ink from the ink reservoir can be pumped by the flow pump into the doctor chamber, with subsequently it being possible that ink is conveyed back via the return flow pump into the ink reservoir. This represents the normal inking process for the doctor device, particularly the anilox roll of the rotary printing press. The valves provided between the doctor chamber and the two pumps may, for example, be switched such, particularly closed, that only one fluid flow develops from the flow pump through the bypass line in the direction towards the return flow pump. This blockage of the doctor chamber can be important, for example when the doctor chamber has already been washed with the solvent and during the removal of the solvent soiled with ink a renewed soiling of the doctor chamber by the conveyance system shall be prevented. 
     It is also possible for the conveyance system to provide a compressed air system, which can be activated after the second cleaning step so that compressed air is conveyed through the flow pump and the return flow pump, resulting in residual ink present in the flow pump and the return flow pump being removed, achieving a cleaning of the flow pump and the return flow pump. Here, it may be useful to introduced compressed air from 3 to 5 bars into the conveyance system in order to reliably release residual ink from both the flow pump as well as the return flow pump, which then can be conveyed into the ink reservoir. It may be advantageous to use the bypass line between the primary drainage line and the primary supply line for the cleaning of the flow pump and the return flow pump, this means that the compressed air is guided downstream the flow pump directly into the bypass line, with the emitted compressed air still being further conveyed out of the bypass line towards the return flow pump. Advantageously the valves arranged between the doctor chamber and the pumps are closed so that no compressed air can enter the doctor chamber. This way it is advantageously intended that the already cleaned doctor chamber is not resoiled with ink residue released from the pumps due to the inflowing compressed air. 
     Additionally, the invention may provide that the primary supply line and the primary drainage line comprise connection elements, which allow a connection to the ink reservoir and/or to the storage container. The connection elements are a part of the color system, with the connection element projecting into the ink reservoir and representing a part of the primary supply line. The other connection element is a part of the primary drainage line and also projects into the ink reservoir. During the printing process the ink flows through these connection elements as well. During a color change these connection elements also need to be cleaned from ink. On the one hand, these connection elements are cleaned and/or preliminarily cleaned during the first cleaning step due to the solvent flowing through them. An improving measure of the invention may include that the conveyance system comprises a supplementary cleaning device, which can be activated after the second cleaning step, so that the connection elements are cleaned. Here, it may be advantageous that the supplementary cleaning device supplies compressed air and/or a process solvent to the connection element. For example, it is possible that first a process solvent is pumped through the two connection elements in order to release ink residue from the connection elements. In another step, additional compressed air can be pumped and/or pressed through the connection elements in order to release residual ink and/or residual process solvent from the connection elements. The process solvent can also be introduced during the printing process in order to adjust the desired viscosity of the ink. 
     According to the invention, the compressed air system and/or the supplementary cleaning device can be activated manually and/or automatically started after the second cleaning step. For this purpose, a control and/or regulation may be connected to the color system and/or integrated in the color system. The control and/or regulation initiate the automatic process of pumping off the ink and the solvent as well as the respective cleaning steps, particularly through the compressed air system and/or through the supplementary cleaning device. 
     Additionally, the method according to the invention includes that the conveyance system comprises a detection means, which during the step A) detects when the ink reservoir is empty and/or nearly empty, particularly that the detection means is a sensor element, which is arranged in the primary supply line and/or integrated in the flow pump and/or the return flow pump. Additionally, the detection means can be used for the purpose of detecting during the step B), namely during the process of pumping the solvent out of the ink reservoir, when and/or if the ink reservoir is free from solvent and/or almost free from solvent. This means that the detection means can detect during the step B) when the ink reservoir is empty and/or nearly empty due to the solvent being pumped off in the direction of the refuse container. For example, it is possible that the sensor element is a frequency sensor, which determines particularly the flow rate of the flow pump and/or the return flow pump. 
     It may also be provided that the detection means is arranged in the primary drainage line and/or integrated in the return flow pump, with the function of the detection means being identical to the one described in the previous paragraph. Additionally, it may be provided that the detection means of the primary drainage line detects when the doctor chamber is empty and/or nearly empty. 
     In another advantageous measure of the invention, the method may be designed such that the conveyance system comprises an ink tempering, which is arranged particularly in the primary drainage line. The ink tempering may e.g. represent a heat exchanger, which is arranged at the pressure side of the return flow pump. Advantageously the heat exchanger is embodied as a counter flow—heat exchanger, with particularly heated water flow being guided opposite the direction of flow of the ink in the primary drainage line. A defined ink tempering occurs by heat dissipation of the water towards the ink, which is necessary during the printing process of rotary printing presses in order to allow high quality color printing. This way the viscosity of the ink can also be adjusted. 
     Further, the invention includes a color system for a rotary printing press, with the color system comprising a doctor device with a doctor chamber, in which ink is contained for the printing process of the rotary printing press, an ink reservoir, from which ink can be conveyed into the doctor chamber, and a conveyance system, which allows a conveyance of the ink within the color system. According to the invention, the color system is connected to a storage container, into which ink can be introduced from the color system, with a solvent container, in which solvent can be located for cleaning the color system, as well as a refuse container, into which solvent soiled with ink can be introduced. The conveyance system is embodied such that an automatic process of pumping ink via the conveyance system out of the color system into the storage container can be performed. According to the invention, after the process of pumping off, an automatic cleaning of the color system can be performed using solvent, with it being possible in a first cleaning step to collect the solvent in the ink reservoir. In a second cleaning step, the solvent can then be conveyed out of the ink reservoir via the conveyance system into the refuse container. 
     Advantageously, the conveyance system is designed modularly, forming an assembly, which can subsequently be connected to the color system or is separate from said color system. 
     Additionally, it may be provided that a sensor is arranged in the primary supply line, which determines and/or can determine the viscosity of the ink conveyed through the primary supply line from the ink reservoir to the doctor chamber. The sensor may be an ultrasound sensor. A temperature sensor may also be integrated in the viscosity sensor. 
     Advantageously, the solvent located in the solvent container is different from the solvent used in the supplementary cleaning device. For example, the solvent of the supplementary cleaning device may be a process solvent which represents for example pure ethanol. The solvent of the solvent container may be a cleaning solution, however, which for example is a mixture perhaps showing ethanol as one of its ingredients. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Additional advantages, features, and details of the invention are discernible from the following description, in which an exemplary embodiment of the invention is described in detail with reference to the drawings. Here, the features mentioned in the claims and the description may be essential for the invention individually as well as in any arbitrary combination. It shows: 
         FIG. 1  a color system for a rotary printing press in which a doctor device is inked in its doctor chamber, 
         FIG. 2  the color system according to  FIG. 1 , which is prepared for an automatic process of pumping off the ink located in the color system, 
         FIG. 3  the color system according to  FIG. 1 , in which the ink is pumped out of the color system into a storage container, 
         FIG. 4  a color system according to  FIG. 1 , with the color system being cleaned by a solvent and the solvent initially being collected in an ink reservoir of the color system, and 
         FIG. 5  a color system according to  FIG. 1 , with the solvent located inside the ink reservoir being pumped out of the color system into the refuse container. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
       FIGS. 1 to 5  show a potential exemplary embodiment of a color system  10 , which is arranged in a rotary printing press  1 . Here, the color system  10  primarily serves to supply the doctor device  11  with the respective ink  2  during the printing process of the rotary printing press  1 . The doctor device  11  comprises here a doctor chamber  12 , in which the respective ink quantity is provided by the color system  10 . Via the respective embodiment of the doctor device  11  ink  2  is conveyed from the doctor chamber  12  to a respective printing unit ensuring the print operation of the rotary printing press  1 . 
     In order to provide ink  2  during the normal printing process, the color system  10  comprises an ink reservoir  13 , in which the ink  2  is located. Additionally, a conveyance system  20  is located between the doctor device  11  and the ink reservoir  13 , which is a component of the color system  10 . The conveyance system  20  comprises various pumps  31 ,  41 , lines  30 ,  40 , as well as valves, so that a circuit develops for the ink  2  out of the ink reservoir  13  to the doctor device  11  and back to the ink reservoir  13 . Additionally, the color system  10  is connected to a storage container  60 , a solvent container  70 , as well as a refuse container  80 . During the printing process according to  FIG. 1 , ink  2  flows through the primary supply line  30 , with here the flow pump  31  being activated and ink  2  flowing through the supply line  33 ,  34 . 
     Here, the primary supply line  30  comprises two valves  35 ,  36 , with both valves  35 ,  36  being open. 
     As discernible from  FIG. 1 , the conveyance system  20  comprises a bypass line  21  with a valve  25 , with the bypass line  21  connecting the primary supply line  30  to the primary drainage line  40 . According to  FIG. 1  the valve  25  is closed, so that a circuit for the ink  2  develops only via the doctor chamber  12 . During the printing process of the rotary printing press  1  the return flow pump  41  is also activated so that the drainage line  43  represents the suction side of the return flow pump  41  and the drainage line  44  represents the pressure side of the return flow pump  41 . Additionally, the primary drainage line  40  shows two valves  45 ,  46 , which are open during the printing process according to  FIG. 1 . The primary supply line  30  as well as the primary drainage line  40  are connected via connection elements  32 ,  42 , also embodied as lines, to the ink reservoir  13 , which means that both connection elements  32 ,  42  project into the ink reservoir  13  such that ink  2  can reliably flow out of the connection element  42  into the ink reservoir  13  and can be pumped out of the ink reservoir  13  via the connection element  32  into the primary supply line  30 . 
     The primary supply line  30  comprises a viscosity sensor  24 , which during the fluid flow of the ink  2  through the primary supply line  30  can determine the viscosity of said ink  2 . A control and/or regulation device, not explicitly shown, is connected to the conveyance system  20  and/or the color system  10 , which can adjust and/or monitor the desired viscosity of the ink  2  so that the doctor device  11  shows the optimal viscosity feature of the ink  2 , which is important for the printing process and the printing quality. For example, the viscosity can be adjusted via changes of the temperature of the ink as well as the supply of additives and/or process solvents. The primary drainage line  40  comprises an ink tempering  23 , which is arranged on the pressure side of the return flow pump  41 . In the present exemplary embodiment, the ink tempering  23  is a heat exchanger, which shows a water supply line  26  and a water return line  27 . The ink flow in the primary drainage line  40  is aligned opposite in reference to the water flow of the heat exchanger  23 . Additionally, the color system  10  comprises a compressed air system  50  as well as a supplementary cleaning device  90 , which is discussed in the following. 
     When the printing process of the rotary printing press  1  is interrupted, an automatic cleaning process of the color system  10  can occur. Among other things, it is important that any damaging drying of the ink  2  contained in the doctor device  11  is prevented. According to  FIG. 2 , a status analysis is shown to prepare an automatic process of pumping the ink  2  out of the color system  10 , with the option being provided to convey the ink  2  into a storage container  60 . The storage container  60  is connected via a connection element  62  of the color system  10  to the conveyance system  20 . A line  61  with a valve  64  ensures that ink  2  can be pumped into the storage container  60 , which is shown in  FIG. 3 . By opening the valve  64  and closing the valve  46  of the primary drainage line  40  here ink  2  reaches the storage container  60 . Both pumps  31 ,  41  are active simultaneously. Additionally, the color system  10 , particularly the conveyance system  20 , comprises a detection means  22 , which during the process of pumping the ink  2  out of the color system detects when the ink reservoir  13  is empty and/or nearly empty. In the present exemplary embodiment the detection means  22  is embodied as a sensor element and a frequency sensor, which is integrated in the flow pump  31 . From the flow rate and/or the detection of a higher frequency of the flow pump  31  the detection means  22  can conclude that the ink reservoir  13  has been pumped almost empty. Subsequently an automatic cleaning of the color system  10  occurs using a solvent  3 , which is located in the solvent container  70 . By opening the valve  72  the solvent  3  flows through the line  71  and reaches the primary supply line  30 , in which it is pumped by the pumps  31 ,  41  to the doctor device  11  as well as into the ink reservoir  13 . Simultaneously the valve  36  is closed so that it is avoided that the solvent  3  flowing into the ink reservoir  13 , which can be enriched with ink  2 , can return into the primary drainage line  40 . The solvent  3  cleans all lines  30 ,  40  as well as the doctor chamber  12  so that a large portion of the ink residue can be transported from the color system  10  into the ink reservoir  13 . 
     Additionally, it is possible that another cleaning system can be activated automatically and/or manually, so that via the supply of compressed air through the line  51  another ink cleaning effect occurs within the return flow pump  41  as well as the flow pump  31 . 
     Residual amounts of ink  2  can be released from the pumps  31 ,  41  by appropriately compressed air which can be subsequently transported and/or conveyed into the ink reservoir  13 . The supply of compressed air occurs such that the valve  52  of the compressed air system  50  is opened, with simultaneously the valve  72  being closed. For the rest, the valve positions remain in their respective setting, which is indicated respectively in  FIG. 4 . If after a defined period of time the valve  52  is closed, it is possible to briefly open the valve  72  and activate the pump  41 , in order to once more rinse the conveyance system  20  with solvent  3 . 
     Alternatively and/or in addition to the compressed air system  50  a supplementary cleaning device  90  may be provided, which ensures that the connection elements  32 ,  42 ,  62  are cleaned, which means that ink residue is released from the above-mentioned connection elements  32 ,  42 ,  62 . The supplementary cleaning device  90  comprises a line  97  with a valve  96 , with it being possible in an open position of the valve  96  that compressed air can be pumped into the primary drainage line  40  and the primary supply line  30  in order to clean the connection elements  42 . For this purpose the valves  94 ,  95  at the lines  92 ,  93  are opened. Simultaneously, the valves  46  and  36  are closed. Subsequently and/or alternatively another solvent can be pumped into the conveyance system  20  via the line  91 , with the valve  96  being closed and the valves  94 ,  95  remaining open. Here, too the valves  46 ,  36  are closed. This solvent additionally cleans the connection elements  32 ,  42 . It is also possible, using a line not explicitly shown, to clean the connection element  62  according to the two so-called cleaning methods (compressed air and/or solvent). After the cleaning process, now the solvent  3 , which is contained in the ink reservoir  13  with ink residue  2  from the color system  10 , can be pumped into the refuse container  80 . This is shown in  FIG. 5 , with the valves  35 ,  45  of both primary lines  30 ,  40  being closed in order to prevent that the solvent  3  soiled with ink  2  can enter the doctor chamber  12 . The valve  25  is open so that the solvent  3  can be pumped from the primary supply line  30  through the bypass line  21  to the primary drainage line  40 . The valve  46  is also closed so that the solvent  3  is conveyed via the open valve  82  and the line  81  into the refuse container  80 . It may be provided, for example, that only the pump  41  of the primary drainage line  40  is active in order to prevent that, in case of a potential leak of the valve  35 , any solvent  3  can flow into the doctor chamber  12 . 
     It is also possible to change the viscosity of the ink  2  during the printing process, using the supplementary cleaning device  90 . Here, processing solvent can be mixed to the ink  2  via the line  91  as well as the open valve  94 . A respective mixing occurs in the ink reservoir  13 , for example using a mixer or an agitator. 
     It is also possible for the detection means  22  to be arranged in the primary drainage line  40 , particularly the return flow pump  41 , or integrated in the return flow pump  41 . The functionality of this detection means  22  is equivalent to the description of the detection means  22  located at the flow pump  31 . Additionally, it may be provided that the detection means  22  of the primary drainage line  40  detects when the doctor chamber  12  is empty and/or nearly empty. 
     The invention being thus described, it will be apparent that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be recognized by one skilled in the art are intended to be included within the scope of the following claims. 
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 List of Reference Characters 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1 
                 Rotary printing press 
               
               
                 2 
                 Ink 
               
               
                 3 
                 Solvent 
               
               
                 10 
                 Color system 
               
               
                 11 
                 Doctor device 
               
               
                 12 
                 Doctor chamber 
               
               
                 13 
                 Ink reservoir 
               
               
                 20 
                 Conveyance system 
               
               
                 21 
                 Bypass line 
               
               
                 22 
                 Detection means 
               
               
                 23 
                 Ink tempering, heat exchanger 
               
               
                 24 
                 Viscosity meter, viscosity exchanger 
               
               
                 25 
                 Valve 
               
               
                 26 
                 Water supply line 
               
               
                 27 
                 Water return line 
               
               
                 30 
                 Primary supply line 
               
               
                 31 
                 Flow pump 
               
               
                 32 
                 Connection element, socket 
               
               
                 33 
                 Supply line 
               
               
                 34 
                 Supply line 
               
               
                 35 
                 Valve 
               
               
                 36 
                 Valve 
               
               
                 40 
                 Primary drainage line 
               
               
                 41 
                 Return flow pump 
               
               
                 42 
                 Connection element, socket 
               
               
                 43 
                 Drainage line 
               
               
                 44 
                 Drainage line 
               
               
                 45 
                 Valve 
               
               
                 46 
                 Valve 
               
               
                 50 
                 Compressed air system 
               
               
                 51 
                 Supply line 
               
               
                 52 
                 Valve 
               
               
                 60 
                 Storage container 
               
               
                 61 
                 Line 
               
               
                 62 
                 Connection element 
               
               
                 64 
                 Valve 
               
               
                 70 
                 Container for solvent 
               
               
                 71 
                 Solvent supply line 
               
               
                 72 
                 Valve 
               
               
                 80 
                 Refuse container 
               
               
                 81 
                 Supply line 
               
               
                 82 
                 Valve 
               
               
                 90 
                 Supplementary cleaning device 
               
               
                 91 
                 Line 
               
               
                 92 
                 Line 
               
               
                 93 
                 Line 
               
               
                 94 
                 Valve 
               
               
                 95 
                 Valve 
               
               
                 96 
                 Valve 
               
               
                 97 
                 Line