EP1828850B1 - Method, device and computer program for producing a developer mixture in an electrographic developer station - Google Patents

Abstract

The invention relates to a method for producing a developer mixture in a developer station (14, 16/1 16/5) of an electrographic printing device. According to said method, the developer station (14, 16/1 16/5) is simultaneously filled with ferromagnetic carrier particles and toner. In the event of a malfunction, the filling process is continued, using the last detected quantity of carrier particles and/or toner, in a predetermined process step.

Description

The invention relates to a method and apparatus for generating a developer mixture in a developer station for an electrographic printer or copier. Such devices operate according to the electrographic principle, in which image information is transmitted by e.g. electrical, magnetic and / or optical signals are generated as electrical charge or magnetic fields on an intermediate carrier point by point and the intermediate carrier is dot-wise inked with toner. The coloring is accomplished in particular with a two-component developer mixture and can proceed by means of a magnetic brush produced with magnets or according to the so-called toner jump principle. The developer mixture contains charged and / or magnetized particles, so-called carrier particles, and toner. The toner image is then on a recording medium, especially on paper, reprintable.

A working according to the electrophotographic principle printing device in which the image information is generated by means of light on a photoconductive layer, is from the DE-C1-19540138 known. From the WO-A1-98 / 27472 For example, a developer station operating on the toner jump method is known.

From the US-A-4,511,639 is a method of regenerating a developer mixture in an electrophotographic printing system known. Although such methods can increase the life of the developer mixture, it is sometimes necessary to completely renew the mixture to ensure high quality of the printed images.

From the EP-B1-1 016 935 a printing system is known in which aggregates such as a developer station have an electrical memory for storing operating values.

From the WO-A2-02 / 067060 For example, a method for continuously exchanging carrier particles in a developer station is known.

From the WO-A1-98 / 39691 An electrophotographic printing machine is known which has a plurality of developer stations. The WO-A1-98 / 27466 shows a corresponding device.

From the US-A-5,592,270 A method is known for filling an electrophotographic developer station with carrier particles and toner, wherein the inflows of toner and carrier particles are each separately controllable.

From the EP-B1-1 016 935 a printing device is known in which various units are provided with an electronic memory element in which aggregate-specific values can be permanently stored.

The above publications are hereby incorporated by reference into the present specification.

In large electrographic printing devices with high printing powers of a few tens of pages of DIN A 4 per minute to over 1000 pages of DIN A4 per minute, relatively large amounts of developer mixtures have to be provided. This provision is relatively time consuming in such devices, when the toner and the ferromagnetic carrier particles are mixed only in the developer station and are additionally activated must, ie be continuously mixed with each other over a certain minimum period to build a triboelectric potential in the developer mixture. The time required is particularly disadvantageous because during this time the printing machine is out of operation.

It is an object of the invention to improve developer-related processes for electrographic devices.

This object is achieved by the invention specified in the independent claims. Advantageous embodiments of the invention are the subject of the dependent claims.

According to a first aspect of the invention, to generate a developer mixture in a developer station of an electrographic printing apparatus, magnetizable, especially ferromagnetic carrier particles and toner are simultaneously introduced into the developer station. This achieves a process parallelization of the two filling processes.

By parallelizing individual phases of the overall process "mixture change" a significant time optimization is achieved. If a device has multiple developer stations, a further optimization of the time sequences and thus a reduction of the printer downtime, ie the times in which no printing operation is possible, can be achieved, that the filling of the various developer stations at least partially takes place in parallel or simultane- ously , In this case, it may in particular be provided that the developer stations each have their own device for monitoring the aging state of the mixture, for example a counter for the number of pages printed with the mixture, but that an exchange of several developer mixtures takes place simultaneously for all these mixtures, as soon as first mixture has reached its life limit, for example, by reaching a predetermined upper counter limit of the page counter. In a further In a more refined embodiment, the simultaneous replacement of a further developer mixture can be made dependent on whether its age state has reached a certain minimum degree of substitution, for example if its page counter has reached a so-called lower replacement threshold, which is below said upper counter limit value.

In particular, three phases for generating a developer mixture are: Carrier filling, toner-toning (i.e., toner filling), and mixing (mixing).

• Carrier einfüllen: In dieser Phase wird das Trägermaterial - Carrier - in die Entwicklerstation gefüllt.
• Auftonern: Der eingefüllte Carrier besitzt keinen Toner. Um drucken zu können muss eine gewisse Tonerkonzentration vorhanden sein. Um dies zu erreichen wird ein neu eingefülltes Gemisch aufgetonert. Dabei werden eine festgelegte Anzahl von Förderzyklen durchgeführt, die die nötige Tonermenge zum Carrier transportieren.
• Durchmischen (Mixing): Der Carrier und der Toner müssen durchmischt werden, um eine gleichmäßige Verteilung zu erhalten und sich elektrisch aufzuladen. Diese Aufladung des Carriers und speziell des Toners ist notwendig um den Druckprozess überhaupt durchführen zu können.

These phases can be described as follows:

• Loading Carrier: In this phase, the carrier material - carrier - is filled into the developer station.
• Toner: The filled carrier has no toner. To be able to print, a certain amount of toner must be present. To achieve this, a newly filled mixture is toned. In this case, a fixed number of delivery cycles are performed, which transport the necessary amount of toner to the carrier.
• Mixing: The carrier and the toner must be mixed to obtain an even distribution and to charge electrically. This charging of the carrier and especially of the toner is necessary to be able to carry out the printing process at all.

To solve the problem, the individual processes are filled with carriers and run on toner at the same time. In particular, the two processes can be coordinated so that first the carrier is filled and switches on the Auftonerprozess after a defined time. The time is reasonable for some carrier to be in the developer station before the first toner is added. Both In particular, processes end at the same time. The mixing takes place in particular simultaneously with the other two processes. At the same time, the parallel processes of conveying the carrier and toner fulfill the function of the mixing phase. Furthermore, it is possible to additionally carry out a mixing phase of any time by changing the parameters, if required. The possibility is particularly advantageous because it may require a longer activation for certain toners or carriers.

Due to the parallelization, the individual phases of a mixture preparation, which have hitherto been carried out strictly one after the other, are pushed into one another temporally, which leads to a significant optimization of the time. The lower process time results in a more pleasant handling of the printer and less waiting time during the mixture change. In addition, the mixture ages less because it is less stressed.

For the first time, processes according to the invention are parallelized, which were carried out successively in previously known traversers. It is filled with carrier and toner at the same time with a certain delay that is necessary. As a result, the processes can be intertwined and the overall process time can be significantly reduced.

1. (a) eine erste Phase, in der ein verbrauchtes Entwicklergemisch aus der Entwicklerstation abgelassen wird und
2. (b) eine zweite Phase, in der ein neues Entwicklergemisch erzeugt wird indem neue Trägerteilchen und Toner in die Entwicklerstation prozessschrittweise oder kontinuierlich eingefüllt und miteinander durchmischt werden, wobei die Menge der zugeführten Trägerteilchen und/oder des zugeführten Toners regelmäßig, insbesondere prozesschrittweise automatisch erfasst werden.

The mixing phase for mixing and activating the mixture is carried out in parallel, wherein the common filling of the developer station is sufficient to activate the resulting mixture. Activate means that the toner and carrier charge in the opposite direction due to the friction during mixing. If there are mixtures that have different properties and require a longer mixing phase, a separate mixing phase can be provided in the process, which can be activated by changing the parameters if necessary. According to a second aspect of the invention, which may be performed in combination or independently of the first aspect, a method for computer-assisted changing a developer mixture in a developer station of an electrographic printing apparatus comprises:

1. (a) a first phase in which a spent developer mixture is discharged from the developer station, and
2. (B) a second phase in which a new developer mixture is produced by new carrier particles and toner in the developer station process stepwise or continuously filled and mixed with each other, wherein the amount of the supplied carrier particles and / or the supplied toner regularly, in particular process stepwise detected automatically ,

In this case, the overall process of the mixture preparation is subdivided in particular into phases and predetermined parameters, in particular quantitative values of the filled-in materials, are recorded during the process. This makes it possible, in the case of a termination of the process during a phase, in particular in an error trap to continue the process controlled in this phase. As a result, partially prepared mixtures can be completed in a controlled manner and do not need to be disposed of.

According to a third aspect of the invention, which may be considered alone or together with the above-mentioned aspects, in a process for changing a developer mixture in an electrographic developer station in the case of failure or abort of the process, a continuation takes place at a predetermined process step, in particular using the last detected amount of carrier particles and / or toner.

The process structure can be done in particular by so-called anchor points. The anchor points serve as reentry points at predetermined process steps in the event that the mixture change sequence is interrupted. Thus, the entire procedure does not have to be run through again from the beginning, but can be continued at the appropriate place in a time-saving manner. In addition, in this way not a possibly newly filled Carrier must be drained and discarded just to the process again (with a new carrier) to start over again (which incurs additional costs). This form of process structure is particularly advantageous when the process is computer controlled.

1. 1. Zähler zum Zählen von Förderzyklen eines Tonertransportmittels während der Auftonerphase. Damit wird bestimmt, wie viel Toner bereits zum neuen Carrier gegeben wurde. Es kann somit genau die noch fehlende Menge Toner in die Entwicklerstation gefördert werden.
2. 2. Zähler bzw. Timer, der den Mixingprozess zeitlich überwacht. Damit wird ausgeschlossen, dass das Gemisch zu lange durchmischt wird, und somit zu lange altert, oder versehentlich zu kurz durchgemischt wird, was zu erheblichen Druckbildproblemen und somit zu einem Fehler führt.

If an error occurs, the process does not have to be completely repeated, but continues at an anchor point. The anchor points are inserted at meaningful and technically feasible points in the process. In order to be able to continue at some, very important points in the mixture change process, it is necessary to introduce new counters, for. As a Übertonerung the developer station to escape. These counters are:

1. 1. counter for counting conveyor cycles of a toner transport during the Auftonerphase. This determines how much toner has already been added to the new carrier. It can thus be promoted exactly the missing amount of toner in the developer station.
2. 2. Counter or timer, which monitors the mixing process in time. This excludes that the mixture is mixed too long, and thus ages too long, or is accidentally mixed too short, which leads to significant print image problems and thus to a mistake.

Advantages: The "anchor points" lead to even greater time savings in the event of a fault. It also prevents developer station errors from occurring (eg over-toning, aging too long, mixture too low). In addition, in the event of a fault, the already filled in carrier and toner need not be removed again and thrown away.

In particular, the above-mentioned toner denoising counter is active during the toner toning phase and counts the number of toner conveying cycles performed. If the process is interrupted during this phase, it will be resumed at this point later ("anchor point"). The process continuation at the anchor point is possible because the number of already completed conveyor cycles are counted, and thus the already promoted in the developer station or the carrier amount toner is known. Thus, for example, a Übertonern the developer station is prevented.

A corresponding counter for counting mixing cycles can also be set up for the mixing phase. As the carrier ages in the course of its lifetime, and this factor is processed by the printer, it is advantageous to know the length of the mixing phase and not stretch unnecessarily long.

According to a third aspect of the invention, which can be seen independently or in combination with either or both of the aforementioned aspects, developer-mix-related status and / or counter data, in particular a full / empty status for the developer station, becomes a state of the phaser, which is the indicating the actual phase of the mixture change or the mixture production and / or the quantity and / or time values recorded during generation of the mixture, stored on a non-volatile, electrical memory of the developer station.

The current status of the developer station - z. B. empty or partially empty - is stored on a non-volatile memory on the developer station itself. The counters described above are also noted on the non-volatile memory. Thus, the information regarding the state of the developer station is no longer just in the printer present but also stored on the developer station itself. Furthermore, a microprocessor can be provided on the developer station, which processes these data. Due to the data stored on it, a developer station can be used at any time, even after a canceled mixture change in another printer or at another time, without running the risk to get into an erroneous state, for example by Überertonerung. In addition, a new carrier, which was already filled at the time the demolition of the mixture change and still aufgetonert must be (partially or completely), continue to be used because the developer station on the basis of the count on the non-volatile memory detects how much toner has already been filled , This can also be done in another printer, since the information of the meter reading and the status (eg: "draining") with the developer station "taken" is.

Hereinafter, embodiments of the invention will be described with reference to a comparison between a conventional printing system (old) and a printing system according to the invention, from which further effects and advantages of the invention will become apparent.

Figur 1:

ein elektrografisches Hochleistungsdruckgerät

Figur 2:

Zusammenhänge beim Wechseln eines Entwicklergemi- sches

Figur 3:

einen Prozess des Gemischablassens

Figur 4:

einen Teilprozess des Absaugens

Figur 5:

einen Prozess zum Einfüllen von Trägerteilchen

Figur 6:

Prozesse des Auftonerns und Durchmischens und

Figur 7:

ein elektrofotografisches Druckgerät mit mehren Ent- wicklerstationen.

Show it:

FIG. 1:

a high performance electrographic printer

FIG. 2:

Connections when changing a developer mix

FIG. 3:

a process of the mixture exhaust

FIG. 4:

a sub-process of sucking

FIG. 5:

a process for filling carrier particles

FIG. 6:

Processes of toning and mixing and

FIG. 7:

an electrophotographic printing machine with several developer stations.

In FIG. 1 schematically an electrophotographic printing device for single or multi-color, one or two-sided printing of tape-shaped recording media 10 of different bandwidth is shown. It contains as an intermediate carrier an electric motor driven photoconductor drum 11. To the intermediate carrier 11 group the various units for the electrophotographic process. These are essentially a charging device 12 in the form of a charging corotron for charging the intermediate carrier 11; a character generator 13 having a light-emitting diode comb for character-dependent exposure of the intermediate carrier 11, which extends over the entire usable width of the intermediate carrier 11; a developer station 14 for coloring the character-dependent charge image on the intermediate carrier 11 by means of a one- or two-component developer mixture; a transfer station 15 which extends across the width of the intermediate carrier 11 and with which the toner images are transferred to the recording medium 10. To remove the residual toner after the development and the transfer printing, a cleaning station 16 is provided with a cleaning brush integrated therein with associated suction device and an unloading device 17. The intermediate carrier 11 is driven by an electric motor and moved in the direction of arrow in printing operation.

Furthermore, the printing device includes a transfer station 15 downstream in the transport direction of the recording medium fuser 18, which is designed as Thermodruckfixierstation, and a fixing station downstream feeder 21 with guide rollers for feeding the recording medium 10 to an internal stacking device 22 or to an outside of the printing device arranged external stacking or other Nachverarbeitungsrichtung.

The tape-shaped recording medium 10 is e.g. as prefolded, provided with Randperforationen continuous paper and is supplied starting from an internal storage area 23 via feed rollers 24 of a swing-off paper diverter the transfer station 15. However, it is also possible to supply a recording medium without edge perforations via a roll feed.

The transport of the recording medium 10 preferably takes place via a transport device 25 assigned to the transfer printing station 15 in the form of transport belts provided with pins, which engage in the peripheral perforations of the recording medium 10 via drive shafts. Furthermore, in the housing portion of the printing device, in a receiving area for the internal storage stack 23, a turning device 28 is arranged over the printed on the back of the already printed on the front side recording medium and again the transfer station 15 is supplied. The turning device 28 is connected to the fixing station 18 via a return channel 29 in connection.

In principle, the aggregates are combined into interchangeable modules in the illustrated printing device, or designed as exchangeable modules. This applies both to the turning device 28, the return channel 29 and to the electrophotographic printing module 26 with the units arranged there for the electrophotographic process. Separately exchangeable in the electrophotographic printing module 26 is the developer station 14. It is mounted for this purpose on rails 27 and can thus be pushed and replaced perpendicular to the plane of the printing device. Their basic structure is from the WO-A1-98 / 27472 known, which is incorporated herein by reference. On the developer station 14, an identification device 30 is arranged in the form of a printed circuit board whose function will be explained later. Furthermore, the developer station contains an automatically controlled mixing excavator, with which the toner-developer mixture can be mixed.

The printing device is controlled via a printer control, not shown. The operation of the printing device via a control panel display 31 in the form of a touch-screen screen.

The identification device 30 mounted on the developer station 14 may consist of a plurality of electronic modules arranged on a printed circuit board which are interconnected via control lines to a microprocessor control and as shown in FIG EP-B1-1 016 935 ( Fig. 2 ) are described in more detail. The variable data about the state or the properties of the developer station are stored in a non-volatile semiconductor memory, in particular in a transponder memory.

In the developer station 14 are arranged a plurality of inductively and analogously operating toner concentration sensors and one or more temperature sensors. The toner concentration sensors inductively determine the ratio of the carrier particles consisting of iron to the toner particles of the developer mixture, taking into account the ambient temperature and the sheet counter reading and possibly taking into account other influencing variables. Thus, the need for fresh toner is determined and notified the device control. This actuates the corresponding Frischtonerzuführeinrichtung in the device. If a mixture change is to be carried out in the developer station 14, a corresponding software program is started via the control panel 31, which computer-controlled the process. As soon as the process of the mixture discharge is started, the developer station must be completely drained off, since otherwise the necessary filling degree (with mixture / carrier) is no longer guaranteed. This status is stored with "not full" (or draining) in the semiconductor memory mounted on the developer station 14.

• 1 leer; 2 not Full; 5 draining; 6 filling Carrier; 3 full With Carrier; 7 filling Toner; 4 full With Developer; 8 expired; 0 undefined.

Overall, the developer station, which operates in the following examples according to the Tribo Jump principle and is also referred to below as TJE, the following states are assigned, wherein the respective digit is stored as a numerical value in the semiconductor memory:

• 1 empty; 2 not full; 5 draining; 6 filling carriers; 3 full with carriers; 7 filling toner; 4 full With Developer; 8 expired; 0 undefined.

In FIG. 2 four sub-processes of a mixture change process and their relationships are shown, namely P1 "discharge mixture", P2 "Carrier fill", P3 "Auftonern" and P4 "mixing". In addition, the respective process time is indicated.

In the accompanying tables corresponding data are given, which are stored in the semiconductor memory of the developer station, e.g. the status value 5 when iterates through the draining subprocess.

The higher-level process control (software) is set up such that the entire process can be aborted when process P1 is completed, ie P2 does not necessarily follow P1. In contrast, the Prozes P3 (toning) is automatically started after a predetermined time (57 sec), after the process P2 (fill in Carrier) has been started. Since the process of "filling in carriers" usually takes 4 minutes and the process of "toning" takes 3 minutes and 3 seconds, the two processes are usually completed at the same time. The toning is done in this embodiment in 37 substeps, each step is stored in a counter on the developer station, so that in case of a termination or an error during toner toning later still needed residual amount of toner can be determined and filled. If an error occurs in the "toning" process, or if it is aborted, it will be automatically resumed later at the point at which it was interrupted. For this purpose, the last stored on the developer station value of the toner meter is read and determined in the printer, the remaining demand on Tonerförderzyklen. In the event of an error occurring during the Carrier filling is queried (automatically or semi-automatically), if the carrier bottle is already empty. Possibly. is moved to the end of the thread to an "AND" hook, waiting for the end of the Auftoner thread. If the carrier bottle is not yet empty, the carrier filling process is continued or restarted.

After completion of the Auftonerns additionally the mixing process P4 can be started, wherein this start and / or the duration of the mixing process P4 can be initiated manually or after measurement of the mixture properties, if necessary, automatically or station or device individually also fixed can be set.

GG(i):

Schritte zum Auslassen von Entwicklergemisch,

F (i):

Fehlerzustand/meldung,

W (i):

Warnmeldung,

GE(i):

Schritte zum Einfüllen von Entwicklerteilchen,

GM(i):

Schritte zum Gemisch auftonern / Durchmischen,

wobei i jeweils eine natürliche Zahl bedeutet.In the following figures, various steps are designated and structured as follows:

GG (i):

Steps to skip developer mix

F (i):

Error state / message,

W (i):

warning

GE (i):

Steps to Fill Developer Particles

GM (i):

Toner toning / mixing steps,

where i is a natural number.

Furthermore, in the FIGS. 3 to 6 Flowcharts shown in which process steps are each indicated in three columns. The middle column has a bright background and describes process steps that are carried out in-house in the developer station and / or in the device control of the printing device. The column to the left of the middle column has a lightly shaded background and, in particular, represents interface method steps supported by the control panel of the printing apparatus, which in particular includes a display device (screen), input devices (touch screen switches) and control panel software. The column to the right of the middle column mainly represents steps for device-internal error and warning messages as well as activation steps for one or more LEDs located on the developer station.

In the Figures 3 and 4 is the software-controlled process P1 "release mixture" in detail, which is supported by a corresponding software program. In this case, also printer-side settings or states that are made via actuators or detected by sensors, taken into account, eg vacuum and blower conditions, service flap settings, door positions, roller tensions, etc. The process has five anchor points A1, A2, A3, A4 and A5, where the process can be resumed if it was aborted at a point past the anchor point and subsequent anchor point. The device control software and the control panel software have appropriate means to assist with the return to anchor points. Column 35 shows the control panel steps, column 36 represents the developer station specific process steps, and column 36 shows the warning messages and light emitting diode (LED) controls.

The catchbox is a container in which spent developer particles and / or toner are filled. Light emitting diodes attached to the developer station and / or displayed on a control panel indicate specific operating states of the TJE through corresponding color indicators. A service flap represents a switch for switching on the negative pressure in the evacuation hose of the developer station, provided that the blower at the developer station is switched on. The developer station is in particular a so-called toner jump developer station (TJE) with a jump roller (JW).

In FIG. 5 the process "fill carrier particles" is shown and in FIG. 6 the process "toning and if necessary mixing". The Submit Developer sub-process has three anchor points A7 when selecting the station, A8 for failure checking, if the carrier bottle is empty, and A9 when removing the developer bottle. The "toning" sub-process has the two anchor points A10 at start and A11 at the continuation of the process with corresponding counter value. The "Mixing" phase has an anchor point A12 on the continuation of the process with a corresponding counter value. As mentioned in the beginning, the process "mixing" (entry at point B of the FIG. 6 ) optionally per device or developer station and can remain unexecuted (Z = 0) depending on the set or selected counter value Z or repeated with Z> 0 mixing steps. The steps / queries GES (2a) "Carrier or Gemsich new or used?" GES (2b) "Enter age" and GE (3) "Open door" are displayed on the control panel and entered if necessary.

In the following, the improvement achievable with the invention will be described on the basis of a comparison with previously available printing systems.

1st reason of optimization

The mixture change in a conventional high-performance printing systems is a relatively lengthy affair and presents, typically about 30 minutes. per developer station a significant downtime in the printing operation. This is particularly serious if the printing device, such as. the Océ Variostream 9000 printing system developed by the applicant has several (up to 14) developer stations. In addition, if an error occurs u.U. the entire mixture change process must be repeated from the beginning. For this purpose, it is also necessary to drain a possibly already filled in carrier again. The drained carrier must also be thrown away mostly, although it is unused.

2nd goal

• Zeitoptimierter Gemischwechsel im Gut- und im Fehlerfall
• Fortsetzung des Gemischwechsels nach einer Unterbrechung, z. B. durch einen Fehler
• Der Status der Entwicklerstation soll erkennbar sein.

The mixture change should be improved, with the following points to be met:

• Time-optimized mixture change in case of good and error
• Continuation of the mixture change after an interruption, z. B. by an error
• The status of the developer station should be recognizable.

3. General

A mixture change is a so-called special function. Special functions are functions outside of "normal" printing operation.

4. Improvements in general 4.1 State of the developer station

The state of the developer station is stored on a non-volatile memory on the developer station itself. If the mixture change is interrupted (intentionally or unintentionally, it can be replaced in the appropriate place and the process is terminated, even if the developer station is inserted in another printer and / or the station is used at a later time). Carrier that has already been filled in does not have to be emptied again because the process does not have to start all over again, for the same reason the mixture change is shortened in the event of a fault.

The possible states of the developer station stored on the non-volatile memory of the developer station are: 1 corresponds to empty The mixture is drained, the developer station is empty. 2 corresponds to not full Both the carrier and the toner are in the developer station, but they are not considered a developer until mixed. 3 corresponds to full with carrier There is Carrier in the developer station 4 corresponds to full With Developer Carrier and toner are in the developer station and the mixing process is complete. Thus, Developer is in the developer station. 5 corresponds to draining The developer station is currently being drained, or has been interrupted during draining. 6 corresponds to filling carrierIm Moment Carrier is filled in the developer station, or has been interrupted during the filling of carrier. 7 corresponds to filling tonerIm Momentum toner is filled in the developer station, or has been interrupted during the filling of toner. 8th corresponds to expired The mixture in the developer station has reached the end of its lifetime. 0 corresponds to undefined The developer station has an undefined state.

The listed states of the developer stations are not only important for the mixture change. They are always important when a station is inserted in a printer or the printer is switched on. In these cases, the deployed developer stations are queried for the printer to determine if it is in a printable state or not. Accordingly, the printer responds and releases the pressure, or "forces" the operator to terminate a possibly interrupted process (mixture change).

4.2 Mixture change counter

• Zähler zum Zählen der Förderzyklen beim Auftonern
  sorgt dafür, dass genau die richtige Menge Toner in die Entwicklerstation gefördert wird.
• Zähler zum Zählen der Mixingzeit
  sorgt dafür, dass Carrier und Toner genau die vorgesehene Zeit durchmischt werden.

In addition to the conditions described in point 4.1, there is more information on the developer station, which, however, important only for the mixture change are. These are two counters that ensure that appropriate procedures are followed during the mix change to avoid serious errors. In addition, they ensure that even if the mixture change is stopped during a "critical" phase, the process can continue at the appropriate point. The counters are:

• Counter for counting the delivery cycles during toning
  ensures that just the right amount of toner is delivered to the developer station.
• Counter for counting the mixing time
  ensures that carrier and toner are thoroughly mixed for the intended time.

Without the counter described here, it could, for. B. come to a Überertonerung, or a poor quality print result, due to a not sufficiently charged mixture.

4.3 anchor points

Anchor points are points in the mixture change that are to be regarded as reentry points. Ie. an interrupted mixture change does not have to be repeated completely from the beginning, but only "falls" back to the last anchor point and ends the procedure from there.

The anchor points are located at meaningful and technically feasible points in the process and thus shorten the process time of the mixture change in the event of a fault, or in case of interruptions.

Particularly important anchor points are the counters shown in section 4.2, which ensure that, for example the exact amount of toner required is conveyed to the developer station.

4.4 Parallelization

The four phases that make up a mixture change have all gone through serially. In order to reduce the process time, some parts of the optimized mixture change are parallelized. These are the sub-processes "filling in carrier", "toning" and sometimes also the "mixing phase". Especially the parallelization of the two phases "filling carrier" and "toning" leads to considerable time reduction.

To implement this measure, the two processes are coordinated. Since it is necessary for some of the carrier to be already in the developer station before toner is added, toning starts a little later than filling the carrier. In addition, the two processes are changed so that they end at about the same time in order to obtain a maximum of temporal optimization.

An extra mixing phase, as hitherto, is currently not necessary, as the two substances are already thoroughly mixed by the parallel supply of toner and carrier. Thus, the mixing is also carried out at the same time. However, it is not excluded that, if necessary, an additional separate mixing phase is performed.

5. Improvements to the process

• Gemisch ablassen
• Carrier einfüllen
• Auftonern
• Mixing (bzw. Durchmischen oder Aktivieren)

The mixture change consists of four parts:

• Drain mixture
• Fill in carrier
• filling toner
• Mixing (or mixing or activating)

The parts are explained in detail and the corresponding advantages and improvements are explained.

5.1 Step 1: Drain mixture

Process time: new 8:20 min old 8:20 min

Generally:

In the first part of the mixture change, the mixture in the developer station is drained off. This step can not be shortened, compared to the existing mixture change, since it must be ensured that all the material in the developer station is sucked off (with the exception of a few hundred grams which can not be removed). As soon as the suction process is started, the developer station gets draining. This means that the suction process has started and that the original amount of mixture in the developer station is no longer present. There is no statement as to how much mixture is still in the developer station or was discharged. If the process is interrupted or stopped, it is impossible to print with this station as draining does not allow it. Even if the developer station is inserted into another printer of the same type, the state is recognized because the information is stored on the developer station.

If the entire mixture is drained, the station receives the status "empty". With this state, the process "carrier The process may also be terminated because the developer station has been emptied for transport, for example.

Error:

If an error occurs during the discharge of the mixture or the process is interrupted, the process must be completely repeated. The reason for this is the risk that a not completely empty developer station, which is not recognized as such, holds. The use of such a developer station can lead to their total failure. Therefore, for the first sub-step of the mixture change - drain the mixture - no counter or timer introduced to continue at the appropriate place, but the complete sub-step must be repeated to ensure that the entire mixture is emptied.

5.2 Step 2: Fill in carrier

Process time: new 4:00 min old 5:00 min

General :

In this phase of the mixture change, carrier is filled into the empty developer station. The developer slips through a hose into the developer station, driven solely by gravity. As soon as the process has started, the developer station receives the status "filling carrier". When the process is finished, a query is made as to whether the entire carrier has slipped out of the bottle into the developer station. If the query is confirmed, the developer station receives the state "full with carrier", if it is no, the filling process is repeated. Normally, however, the time should be sufficient to fill the entire carrier. Actually The time required for the carrier to flow from the bottle to the developer station is about two minutes. The process time itself is therefore reduced from five to four minutes.

Error:

If the process is interrupted, a query is made whether the entire carrier has flowed into the developer station, d. H. if the carrier bottle is empty. Accordingly, the filling process is completed or repeated.

5.3 Step 3: Toner up

Process time: new 3:03 min The sub-step is carried out parallel to the "Carrier filling". Thus, the time to be estimated in the overall process for this process step is: new 0:00 min old 4:51 min

Delivery cycle: 37 delivery cycles must be carried out with the following sample New 3 sec. promote / 2 sec. Break old 3 sec. promote / 5 sec. Break

General :

The carrier must be supplied with enough toner to contain 6.4% toner. 37 delivery cycles are necessary for this. The conveyor cycles are counted and stored continuously on the developer station.

The "Toning" sub-step is carried out parallel to the "Carrier filling", which has not been the case so far. It is important that already some carriers in the developer station is before the toner is conveyed, since then mix both elements better. Therefore toning starts a little later (57 sec.) Than filling the carrier. The time of 57 sec. It is also useful between the beginning of the two phases - "filling in carrier" and "toning" - as both phases end at the same time.

Error:

If an error occurs during "toning" or if the process is stopped, the process will continue exactly at the point at which it was interrupted. Since the number of already completed funding cycles are stored on the developer station, it is known how many cycles have yet to be done. Thus, an over- or undertoning is excluded.

5.4 4th step: Mixing / mixing

Process time: new 0:00 min old 5:00 min

General :

In the mixing phase, the carrier and the toner are mixed. Due to the frictional resistance occurring, the two substances are charged, d. H. activated. In addition, the two substances mix. The charging of the toner and carrier is important because it can only be printed with a sufficiently activated mixture.

So far, a mixing phase of 5:00 min. carried out. Due to the new, simultaneous filling of carrier and toner, a good mixing is already achieved during the phases "Carrier filling" and "Auftonern". The mixing during these phases is sufficient to achieve the necessary activation. Thus the time of the mixing phase is at 0:00 min. reduced. However, the mixing phase is present as a process, and can be done as needed be activated at any time. For this, the corresponding parameter, which specifies the duration of the mixing phase, must be set to the desired time. If the parameter is greater than zero, the mixing phase inevitably follows the "Carrier Filling" and "Toning".

Error:

If an error occurs during the mixing phase, or if the process is stopped, the process will resume exactly at the point at which it was interrupted. To make this possible, the time that the two substances have already been mixed is permanently stored on the developer station. After an interruption, the counter or timer of the developer station is used. This behavior is analogous to the behavior when an error occurs during toning.

5.5 Time comparison of old and new mixture changes

The parallelization and shortening of the individual steps of the mixture change results in the following total process time: New mixture: 12:20 min Mixture change old: 23:11 min

To be added u. U. a mixing time. However, this is not provided in principle and thus only with appropriate knowledge of a special case or introduce generally changed conditions.

In FIG. 7 a printing device is shown with a plurality of developer stations, which are optionally provided for printing with different colors and / or for a double-sided printing on a recording medium. It is in particular with features of WO-A1-98 / 39691 and the WO-A1-98 / 27466 fitted, the contents of which are hereby incorporated by reference into the present description. With the present invention, it is then possible in particular to exchange the developer mixtures of several developer stations in parallel or completely or at least partially simultaneously.

That in the Fig. 7 shown printing device for performance-adapted, monochrome and / or colored, one or two-sided printing a tape-shaped record carrier is constructed in a modular manner and has in principle a feed module M1, a print module M2, a fixing module M3 and a Nachverarbeitungsmodul M4. The feed module M1 contains the elements for feeding a continuous paper, for example drawn from a stacker, to the printing module M2. The printing module M2 contains the actually electrophotographic printing units which print the recording medium, which is then fixed in the fixing module M3 and cut or stacked in the post-processing module M4.

The modules in detail:

The printing module M2 contains the necessary for the printing of a tape-shaped recording medium 10 with toner images aggregates, which are arranged on both sides of a transport channel 11 for the recording medium 10. These units consist essentially of two differently configurable electrophotography modules E1 and E2 with associated transfer modules T1 and T2. The modules E1 and T1 are assigned to the front side of the recording medium 10 and the modules E2 and T2 to the back. The identical constructed electrophotography modules E1 and E2 comprise a seamless photoconductor belt 13a guided via deflecting rollers 12a and driven by electromotives in the direction of the arrow, for example an organic photoconductor (OPC). Along the photosensitive outside, the aggregates for the electrophotographic process are arranged. They serve to single on the photoconductor Color separations associated toner images to produce. For this purpose, the photoconductor moving in the direction of the arrow is first charged to a voltage of about -600 V with the aid of a charging device 14a and then discharged to about -50 volts depending on the character with the aid of a character generator 15a comprising a light-emitting diode comb (LED comb). The photogenerated charge latent image thus formed is then toned with the aid of developer stations 16/1 to 16/5, and then the image is loosened by means of the intermediate exposure means 17a and carried on a transfer belt 19a of the transfer ribbon module T1 in a transfer area 18a Help a transmission corona device 20 a transfer. Thereafter, with the help of Entladekoronaeinrichtung 21a, the entire photoconductor belt is discharged over the entire width and cleaned by a cleaning device 22a with cleaning brush of adhering toner dust. A subsequent intermediate exposure device 23a ensures a corresponding charge-conditioning of the photoconductor belt 13a, which is then uniformly charged, as already described, with the aid of the charging device 14a.

With the electrophotography module E1 or E2 individual color separations of the color image to be generated associated toner images are generated. For this purpose, the developer stations are 16/1 to 16/5 switchable. They each contain the toner associated with a single color separation. For example, developer station 16/1 contains black toner, developer station 16/2 yellow toner, developer station 16/3 magenta toner, developer station 16/4 cyan toner, and blue developer station 16/5, for example Toner or toner of a special color. As developer stations, both one-component and two-component toner developer stations can be used.

In the operation of the printing device is on the developer station 16/1 to 16/5, always by a single developer station produces a toner image associated with a single color separation. This toner image is then electrostatically transferred to the transfer belt 19a of the transfer module T1 via the transfer device 18a in conjunction with the transferor corona device 20a. The transfer module T1 contains the transfer belt 19a, which consists of polyimide or a similar substance, and is guided around a plurality of deflection devices and driven by a motor. The transfer belt 19a is formed like the photoconductor belt 13a endlessly and without seam. It is moved in the arrow direction and starting from the transfer area with the roller 18a and the transfer corona device 20a to a transfer station 24a and from there further to a guide roller 25a to a cleaning station 26a and from there to the transfer area 18a, 20a with the deflection roller 27a arranged there.

The transfer belt 19a in the transfer module T1 functions as a collector for the individual toner images associated with the color separations, which are transferred to the transfer belt 19a via the transfer device 18a, 20a. The individual toner images are arranged one above the other so that an overall toner image corresponding to the color image is formed. In order to be able to produce the total color toner image and then to transfer it to the front side of the recording medium 10, the transfer module T1 contains a switchable transfer station 24a. This can, according to the representation of Fig. 1 , Several, mechanically displaceable transfer rolls 28a included with associated Umdruckkoronaeinrichtung 29a. In the "collect" operating state, transfer rolls 28a and transfer corona 29a are shifted upward in the direction of the arrow, so that the transfer ribbon 19a is spaced from the record carrier 10a. The individual toner images are taken over in this state by the electrophotography module E1 and superimposed on the transfer belt 19a. The cleaning station 26a is deactivated by pivoting. The recording medium 10 is at rest in this operating state in the region of the transfer printing station 24a.

The electrophotography module E2 and the rear-side transfer module T2 of the recording medium 10 are constructed according to the modules E1 and T1. Again, a Sammelfarbtonerbild for the back is generated on the transfer belt T2, wherein in the operating state "collecting" here, the corresponding transfer station 24a is pivoted.

For simultaneous printing on the front and rear side of the recording medium 10a, the transfer belts 19a of the transfer modules T1 and T2 are simultaneously brought into contact with the record carrier 10 in the area of their transfer stations 24a, thereby moving the record carrier 10. At the same time, the cleaning stations 26a of the transfer modules T1 and T2 are swiveled in and activated. After transfer of the two toner images to the front and the back of the recording medium 10a adhering toner image residues on the transfer belts 19a are removed via the cleaning stations 26a. This is followed again by a collecting cycle for the generation of new toner images, in which the transfer belts 19a are swung off and the recording medium 10 is at a standstill. The transfer of toner images from the transfer modules T1 and T2 on the recording medium 10 thus takes place in the start-stop operation of the recording medium.

The recording medium 10 is moved in the feed module M1 from a stacking device 31a via a loop puller 30a to the printing module M2 and there in the paper transport channel 11a by means of motor-driven transport rollers 38a. In the area between the transport rollers 38a and the transfer printing stations 24a, loading or corona devices 39a for paper conditioning may be arranged so that the paper carrier web 10, which is made of paper, can be charged, e.g. is set evenly.

After the transfer of both colored toner images in the area of the transfer printing stations 24a on the recording medium 10, these still have to be fixed. This purpose is served by the fixing module M3. It includes an upper and lower row of infrared radiators 32a between which the paper transport channel for the record carrier 10 extends. Since there is a loose toner image both on the front side and on the rear side of the recording medium, the recording medium 10 is guided freely in the region of the infrared steels 32a via a deflecting roller 33a arranged on the output side. The fixation takes place via the heat of the infrared radiator 32a. In a subsequent cooling section with cooling elements 34a and deflecting rollers 35a to the infrared radiators 32a, cooling of the recording medium 10 and smoothing take place, for example, via corresponding decurler devices. In particular fan-driven air chambers can serve as cooling elements 34a.

After fixing both toner images and cooling, a corresponding post-processing of the recording medium 10 takes place in the context of the post-processing module M4, which is e.g. may include a cutting device 36a with stacking device 37a.

Furthermore, a microprocessor-controlled control device ST coupled to the device controller GS of the printer is provided, which is in communication with the components to be controlled and regulated of feed module M1, print module M2 and fixation module M3 or post-processing module M4. Within the modules it is coupled to the individual aggregates, e.g. with the electrophotography modules E1 and E2 and the transfer modules T1 and T2. Connected to the device control GS or the control ST, which may be part of the device control, is a control panel B, via which the various operating states can be entered. The control panel may include a touch-screen display or a personal computer with a paired keyboard.

Although the invention has been described above primarily with reference to printing devices having an electrophotographic printing process, it is clear that they are also applicable to other printing devices or printing processes in which toner and carrier particles are combined to form a developer mixture. These include, in particular, magnetography and ionography. Instead of the described LED comb for exposure of a photoconductor other controllable light sources such as lasers can be used.

The invention is particularly suitable for being executed fully or partially automatically by means of a computer program (software). It can thus also be distributed as a computer program module, as a file on a data medium such as a floppy disk or CD-ROM or as a file via a data or communication network. Such and comparable computer program products or computer program elements are also embodiments of the invention. The process according to the invention can be used in a computer, in a printing device or in a printing system. It is clear that corresponding computer to which the invention is applied, further, known per se technical devices such as input means (keyboard, mouse, touch screen), a microprocessor, a data or control bus, a display device (monitor, display) and can contain a memory, a hard disk space and a network card.

Various embodiments of the invention have been described. It is clear that the skilled person can always specify modifications and developments. For example, the invention can also be applied to a printing system in which sheet-shaped recording media are processed instead of tape-shaped recording media. Furthermore, it is clear that figures are to be understood only as examples and can be varied at any time without departing from the inventive concept.

LIST OF REFERENCE NUMBERS

10

Record carrier, paper

11

Photoconductor drum

12

loader

13

character generator

14

developer station

15

transfer station

16

cleaning station

17

unloading

18

fuser

21

feeding

22

internal stacker

23

storage area

24

feed rollers

25

transport means

26

print module

27

rails

28

turning device

29

Return channel

30

identification system

31

Control panel

35

Column of the control panel steps

36

Column of TJE station steps

37

Column of warning and display messages

11a

transport channel

12a

deflection rollers

13a

photoconductor

14a

loader

15a

character generator

1.16

to

5.16

developer stations

17a

Between exposure device

18a

Transfer device, transfer area

19a

transfer tape

20a

Transfer corona device

21a

Endladekoronaeinrichtung

22a

cleaning station

23a

Between exposure device

24a

transfer station

25a

deflecting

26a

cleaning station

27a

deflecting

28a

transfer printing

29a

Umdruckkorotron

30a

loop puller

31a

stacker

32a

infrared Heaters

33a

deflecting

34a

cooling element

35a

deflecting

36a

cutter

37a

stacker

38a

transport rollers

39a

Charging corona device

A1 ... A12:

anchor points

B

control panel

E1

Electrophotography module, front

E2

Electrophotography module, back side

GS

device control

M1

feeder module

M2

print module

M3

fuser

M4

post-processing

ST

control device

T1

Transfer module, front

T2

Transfer module, back

Claims (17)

1. A method for generating a developer mixture in a developer station (14, 16/1...16/5) of an electrographic printing device, wherein magnetizable carrier particles and toner are simultaneously filled into the developer station (14, 16/1...16/5) and in case of an error or an abortion of the filling process a continuation takes place at a predetermined process step of the method for generating a developer mixture, in particular by using the last acquired amount of carrier particles and/or toner.
2. The method according to claim 1, wherein at first only carrier particles are filled into the developer station (14, 16/1...16/5) and after the beginning of the filling process for carrier particles toner is additionally filled into the developer station (14, 16/1...16/5).
3. The method according to claim 2, wherein between the beginning of the filling in of carrier particles and the beginning of the filling in of toner a predetermined amount of time passes by, which is calculated such that a predetermined amount of carrier particles is filled into the developer station (14, 16/1...16/5) before the filling in of the toner is started.
4. The method according to one of the preceding claims, wherein the carrier particles and the toner are mixed simultaneously with the filling process.
5. A method for changing a developer mixture in a developer station (14, 16/1...16/5) of an electrographic printing device, according to one of the preceding claims, comprising:

   (a) a first phase in which a used developer mixture is drained off from the developer station (14, 16/1...16/5) and

   (b) a second phase in which a new developer mixture is generated in that new carrier particles and toner are filled into the developer station (14, 16/1...16/5) process step-by-process step or continuously and are mixed, the amount of carrier particles supplied and/or of toner supplied being automatically acquired regularly, in particular process step-by-process step.
6. A method for changing a developer mixture in a developer station (14, 16/1...16/5) of an electrographic printing or copying device, according to one of the preceding claims, wherein several developer stations (14) are simultaneously filled.
7. The method according to claim 5 or 6, wherein in the second phase a mixing of the carrier particles and of the toner takes place, a parameter for the mixing intensity, in particular the length of the mixing time, being acquired.
8. The method according to one of the claims 5 to 7, characterized in that it is implemented in a computer-assisted manner.
9. A method for operating an electrographic developer station (14, 16/1...16/5), according to one of the preceding claims, in which developer mixture relevant status data are stored on a non-volatile electric memory of the developer station (14, 16/1...16/5).
10. The method according to one of the preceding claims 6 to 9, wherein it is checked whether a first developer station (14, 16/1...16/5) has reached a first status value, which indicates that the developer mixture of this developer station (14, 16/1...16/5) is to be replaced and it is checked for at least another developer station (14, 16/1...16/5) whether it has reached a second status value which indicates that the developer mixture of the second developer station (14, 16/1...16/5) also has to be replaced when the first developer mixture is replaced.
11. The method according to claim 10, wherein the two status values are page counter limits and wherein the second page counter limit is lower than the first page counter limit.
12. The method according to claim 9, 10 or 11, wherein a full/empty status and/or a process phase status is stored in the memory.
13. The method according to one of the claims 9 to 12, wherein amount values and/or time values of carrier particles and/or toner particles acquired during the generation of the developer mixture are stored.
14. The method according to one of the claims 9 to 13, wherein a value for the mixing time of carrier particles and toner is stored.
15. An electrographic printing device, comprising means which implement a method according to one of the claims 1 to 14.
16. A computer program which during loading and execution on a computer performs a method according to one of the claims 1 to 14.
17. A method for operating an electrographic developer station (14, 16/1...16/5),
    in which developer mixture-relevant status data are stored on a non-volatile electric memory of the developer station,
    the method comprising:

    (a) a first phase in which a used developer mixture is drained off from the developer station (14, 16/1...16/5), and

    (b) a second phase in which a new developer mixture is generated in that new carrier particles and toner are filled into the developer station (14, 16/1...16/5) process step-by-process step or continuously and are mixed, the amount of carrier particles supplied and/or of toner supplied being automatically acquired regularly, in particular process step-by-process step and being stored in the memory of the developer station (14, 16/1...16/5).

Images