EP1141785B1 - Electrographic printing device with a sensor for detecting slipping - Google Patents

Abstract

An electrographic printing device has at least one printing unit (10, 12) with a toner image carrier. A printing device for producing a toner image prints at least one mark on a photoconductor belt (22, 36). The toner contained on said photoconductor belt is transferred to a transfer belt (30, 44) at a first transfer point (28, 42) and transferred from said transfer belt to a strip-shaped support material (14) at a second transfer point (32, 46). A sensor (26, 48) situated on the transfer belt (30, 44) detects the passage of the mark and a control unit determines the time that has elapsed between the time of printing and the time at which the mark is detected and controls the transportation of the strip-shaped support material accordingly.

Description

The invention relates to an electrographic printing device with at least one printing unit with a toner image carrier, on its peripheral surface, toner according to an image Distribution can be applied.

Such a printing device is in a printer or copier used, with the help of an electrographic Process applied a latent image on the toner image carrier becomes. This can e.g. by exposing a photoconductor or by magnetizing a magnetically sensitive layer respectively. Toner is deposited on the latent image accordingly the pictorial distribution of the electrical charges or of the magnetic poles. This toner is transferred to a transfer location transferred to a carrier material, generally paper and later fixed on it.

A device with such a printing device should work quickly and be flexible in use. Often, toner images be printed on a form that has form windows in the individual characters are to be printed. The characters positioned exactly within the form window. In the case of multicolor printing, the individual colored drawing files must be printed congruently to create a multicolor image produce. All of this places high demands on the mechanics.

A printing device is described in EP 0523870, at of several drawing files of different colors in succession and spaced apart are generated on a photoconductor belt. The drawing files are opened individually at a transfer location transfer a sheet-shaped recording medium, the Record carriers are repeatedly guided past the transfer location is that the drawing files are as congruent as possible be reprinted. The distance between two successive Drawing files is equal to the scope of the roles on which the Photoconductor tape is running, or a multiple thereof, the individual roles have the same scope. An uneven one Rotary motion, e.g. B. due to an eccentricity the roller axes, then affects all drawing files equal, so that the congruently printed partial images result in a full color image without color errors.

In the known printing device can between the drive rollers and slip occurs in the photoconductor belt. That the unrolled circumference of the drive roller in one revolution is longer than the distance around which the photoconductor band is moved forward. In addition, the mechanics can Change transfer points. When printing on a form e.g. it is important that the toner image is precisely predetermined Form sections are printed. The slip between that Photoconductor belt and the drive rollers is not constant, but can be affected by external influences such as temperature or change humidity or aging. Also the Changes in the mechanics at the transfer points is from outside Influences dependent. These changes can only be made difficult to determine. If due to a slip or one Changing the mechanics the toner images are no longer precise Often it can only be printed on the form noticed late and leads to committee.

DE 198 21 218 shows a printing device in which the different colored partial images congruent on a transfer ribbon should be reprinted. There are several brands on this arranged on the transfer belt, their passage past a sensor is detected. By controlling the rotational speed of the Transfer tape becomes the detection signal of the brands into one Line synchronization signal in a fixed phase relationship held. This requires a considerable amount of circuitry.

Another printing device with the different colored Partial images are copied congruently, is from DE 198 06 551 known. With this printing device becomes everyone Drawing image of a mark on a paper web as a record carrier printed. The reflectivity of the congruently printed one on top of the other Marks is used to check the alignment of the individual drawing files measured to each other. On the basis of this The result of the check is the control of the individual Printing units regulated. This printing device is also a considerable circuitry required. A precise position Printing in a form window can be done with this known Do not reach printing device.

In a printing device known from DE 38 08 620 becomes the leading edge of a sheet-like recording medium detected with a sensor and depending on this detection the Feed of the recording medium controlled.

As a result, it is possible to print in a precise position Form window for a sheet-like record carrier achieve, leads to a tape-shaped recording medium but this does not lead to the desired success.

A printing device is specified in EP 0 281 055, at a position sensor for a drum is provided. Also this printing device can only be used for sheet-like recording media use.

Components are from the Patent Abstract of Japan JP-A-06027829 a printing device known in which on a Transfer ribbon a mark is applied, which together with the transfer belt is moved past a sensor. With help a control detects the passing of the mark and the Circulation speed of the transfer belt determined. Dependent from the result of the determination of the rotational speed with the help of another control on a drive motor acted at this rotational speed of the transfer belt correct to a predetermined value. In this way ensures that the transfer belt is a predetermined Orbital speed.

It is an object of the invention to provide a printing device which is an improper transfer of toner images recognizes.

The task is solved by an electrographic printing device with at least one printing unit with a toner image carrier, on its peripheral surface, toner according to an image Distribution can be applied, the toner image carrier a photoconductor whose outer peripheral surface is covered with a latent Charge image is chargeable and has a transfer belt, on which the toner present on the photoconductor is at a first Transfer point is transferable, means are provided through which a carrier material the transfer belt is guided past that the arranged on it Toner at a second transfer location on the carrier material is transferable, along a peripheral portion of the photoconductor a printing device for forming the toner image is arranged, the at least one mark on the photoconductor prints, at least one sensor is arranged on the transfer belt, which detects the passing of the mark, controls the runtime the mark from when the printing device was printed to determined at the time of detection on the sensor, and dependent from the running time to the transport of the band-shaped carrier material controls.

In the invention, the brand moves in the steady State from the time of registration to the time of transfer printing with constant speed. Therefore, the runtime Determine the time it takes to print the toner image required on the carrier material. If due to a change slip, e.g. due to changed ambient temperature, the print quality deteriorates, this causes Slip change also means a change in the term of the Control is monitored. This is indirectly a change the slip is detected and the printing process can take place accordingly to be controlled. For example, can be used to transport the carrier material can be controlled depending on the duration, for example by stopping printing or by Readjusting the transport speed.

In a further development of the invention, the term is also compared to a predetermined target value, if exceeded or falling below a signal is generated. at there has been a deviation from the specified setpoint Slip changed, or there are changes in the mechanics occurred. Depending on the signal generated can be controlling acted on the transport of the band-shaped carrier material become. Depending on the signal, in one embodiment the invention, the operation of the printing device is interrupted become. This will avoid printing scrap.

According to another example of the invention, in a calibration process determines the base time that of the printing device applied toner image needed to attach to the second Transfer point to be reprinted. The target time mentioned is then determined based on the base time. For example, can the target time is 98% of the basic time. If the term the mark in this case corresponds to the target time ensures that the toner image is exactly where you want it Place is printed on the carrier material.

In a development of the invention, the basic time is at Occurrence of the signal determined again. The signal is like mentioned if the runtime deviates from the target time. That means that the base time has changed and the toner images are no longer in the desired position on the Backing material can be printed. The base time must therefore be new determined and the transport of the band-shaped carrier material can be controlled according to the changed slip. For example, can be the time between the creation of the latent image and the start of the transport of the carrier material to the changed one Base time can be adjusted.

The sensor is preferably close to the second transfer printing point arranged. Then the deviation of the term from the Bottom time especially small. This allows the toner image place very precisely on the carrier material.

A further development is characterized in that the printing device at least one image generation unit for generation a latent charge image on the photoconductor and at least has a developer station with the charge image Ink colors. This enables a uniform print image achieve with high resolution. The printing device can also have multiple developer stations, creating a multi-color print becomes possible.

In a variant of the invention is a second printing unit for generating a toner image on that of the first printing unit facing away from the carrier material. On duplex printing is possible in this way, both then Sides of the carrier material can be printed simultaneously.

According to another aspect of the invention, the electrographic Printing device at least one printing unit with one Toner image carrier, on the circumferential surface of which toner according to a image-shaped distribution can be applied, the toner image carrier a photoconductor, the outer peripheral surface of which a latent charge image can be charged, and a transfer belt the toner present on the photoconductor a first transfer printing point is transferable, means are provided through which a carrier material is guided past the transfer belt so that it is on arranged toner at a second transfer location on the Carrier material is transferable, along a circumferential section of the photoconductor, a printing device for generating the toner image is arranged on the transfer belt at least a mark is arranged, at least one sensor on the transfer belt is arranged, which detects the passing of the mark, a control the turnaround time of the mark on the transfer belt determined, and depending on the orbital period on the Control device acts.

In such a printing device according to the invention successive toner images congruent on the Transfer ribbon can be printed. The orbital period of the brand is based on the detection of the mark passing the sensor determined by the controller, the orbital time at a Change in slip or change in length of the transfer belt also changes. This will make one Change in slippage or a change in length of the belt is detected, and the printing process can be controlled depending on the round trip time become. Although the slip itself or the change in length the transfer belt is not determined, the Arrange toner images precisely on this.

The time between the application of two is preferred successive toner images on the photoconductor on the Determined based on the orbital period. The photoconductor and that Transfer belt run at the same, constant speed. So the toner images can be easily and precisely be placed on the transfer belt.

In the case of a further development, the round trip time is in one calibration process certainly. This stands for the following printing processes a round-trip time is available on the basis of which the Time between two successive toner images can be determined on the photoconductor band. Preferably becomes a calibration process parallel to each printing process carried out. So the printing device can be special can be controlled quickly and precisely.

In a collection mode, the transfer belt is repeated on the passed the first transfer printing point, and with each new one A toner image is then passed onto the transfer belt transfer the previous toner image. That way you can Toner images can be superimposed particularly easily. A cleaning device the transfer belt should be from this be swung away.

The transfer belt is changed every time you pass the carrier material pivoted away so that the Carrier material and smearing of the toner images on the Transfer ribbon is avoided.

A further development is characterized in that on the Based on the round trip time, the time between application two successive toner images on the photoconductor is set so that when you pass the transfer belt printed congruently at the first transfer location become. The transfer belt runs at a constant speed, and a change in the orbital period then means that the length of the transfer belt has changed. So that the toner images must be able to be printed congruently the time between two successive applications Toner images on the photoconductor can be changed.

The mark can be fixed on the transfer belt. For example, can be glued a reflective plate on the transfer ribbon or riveted, or the mark can be a slit be in the transfer belt. This will have a long lifespan and ensures a high accuracy of the determination of the round trip time.

In one development, a reflex sensor is provided as the sensor, which detects the passing of the toner mark. Thereby there is a simple structure.

Fig. 1

ein Ausführungsbeispiel einer Druckeinrichtung mit einem Sensor zum Erfassen einer Marke,

Fig.2

eine schematische Ansicht des Ablaufs eines Druckvorganges der Druckeinrichtung,

Fig.3

ein anderes Ausführungsbeispiel zum mehrfarbigen Drucken, und

Fig.4

einen Ablauf eines Sammelmodus des Ausführungsbeispieles nach Fig.3.

An exemplary embodiment of the invention is explained in more detail below with reference to the drawing. Show it:

Fig. 1

an embodiment of a printing device with a sensor for detecting a mark,

Fig.2

1 shows a schematic view of the sequence of a printing process of the printing device,

Figure 3

another embodiment for multi-color printing, and

Figure 4

a sequence of a collection mode of the embodiment of Figure 3.

Figure 1 shows an embodiment of a printing device with a first printing unit 10 and with a second printing unit 12, the surfaces of a paper web facing away from each other 14 are arranged. The paper web 14 is driven by a drive roller 16 in the direction indicated by arrow A. moved forward. You can also by the drive roller 16 withdrawn again to e.g. a defined restart to realize. In the forward direction behind the printing units 10, 12 are a fixing station 18 and a cooling device 20 arranged in this order along the paper web 14. The printing device and its function is in detail described in WO 98/39691, which forms part of the disclosure this registration is.

The first printing unit 10 has a first photoconductor band 22 which runs on roles that are not discussed here is, and that in the indicated by the arrow B. Direction is moving. There is a first on the first photoconductor band 22 Character generator 24 and a first developer station 26 arranged. The first is at a first transfer printing point 28 Photoconductor tape 22 with a likewise not explained in more detail Rolled first transfer belt 30 in contact, the moves in the direction of arrow C.

The first transfer belt is located at a second transfer printing point 32 30 with the upper surface of the paper web 14 in FIG. 1 Contact. A first reflex light barrier is located near the second transfer printing point 32 34 on the first transfer belt 30 in its direction of movement arranged in front of the second transfer printing point 32.

The second printing unit 12 is similar to the first printing unit 10 built. It has a second photoconductor band 36, one second character generator 38 and a second developer station 40, the second photoconductor band 36 extending in the direction of the Arrow D moves and at a third transfer location 42 a second transfer belt 44 is in contact. This moves itself in the direction of arrow E and stands at a fourth transfer location 46 with the lower surface of the paper web in FIG. 1 14 in contact. A second reflex light barrier 48 is near the fourth transfer printing point 46 on the second transfer belt 44 arranged.

The printing device has a device controller GS for controlling of the printing company. The GS device control has a control panel B connected to which this typed print commands can be. A control ST is with the device control GS connected. The control ST, the device control GS and the control panel B and their function are in WO 98/39691 described in more detail. The control ST is with the character generators 24, 38, the reflex light barriers 34, 48 and with the Drive roller 16 via signal lines or control lines connected, omitted for better clarity in Figure 1 are.

The mode of operation of the first printing unit 10 is described below explained. The same applies to the second printing unit 12. The first character generator 22 applies to the first photoconductor belt 22 24 applied a latent charge image. The character generator 24 can be an LED character generator as he e.g. is described in WO 98/39691, or it can be the latent Generate image using laser diodes. This charge image is colored by the first developer station 26 with toner.

The toner image is transferred to the first at the first transfer printing location 28 Transfer ribbon 30 reprinted. At the second transfer location 32, the toner image is printed on the paper web 14 and in the fixing station 18 fixed. The one heated up by fixing Paper web 14 is then in the cooling device 20 cooled.

In addition, the first character generator 24 increases The beginning of each picture is a mark outside of the actual one Printing area on the first photoconductor tape 22 as a latent Image applied. These brands are also on the first developer station 26 colored with toner and on the first transfer printing point 28 to the first transfer belt 30. These toner marks are from the first retro-reflective sensor 34 recorded. Depending on their acquisition status generates a signal that is transmitted to the control ST becomes.

The basic time is determined in a calibration process Print image from the time of printing on the first character generator 24 until the transfer time on the paper web 14 on the second Transfer location 32 required. The photoconductor belt 22, the transfer belt 30 and the paper web move with the same constant speed. The transport of the paper web 14 becomes dependent on such a time delay this basic time started that the toner images on the second Transfer point 32 exactly in the desired form window be reprinted.

So the deviation of the running time of the toner mark from the time of printing on the first character generator 24 until the time of detection at the first reflex light barrier 34 from the base time is the smallest possible, the first reflex light barrier 34 arranged as close as possible to the second transfer printing point 32. This is the largest part of the route, e.g. 98% monitors the toner image until it is transferred onto the paper web 14 travels. The target time is then 98% of the Base time set. The print image is then printed with the desired one Accuracy printed in the form on the paper web, if the measured running time corresponds to the target time. If there is sufficient space, the retro-reflective sensor can 34 also directly at the second transfer printing point 32 be arranged.

Exceeds or falls below the measured runtime predetermined limit value, the printing operation is interrupted. The paper web 14 is withdrawn to the extent that at restart the printing process the printing without release a gap at the last printing position continued can be. Then a new calibration process is carried out. To do this, the procedure described above can be repeated be carried out, or the new basic time can be done from the last measured transit time or from the mean of the last measured runtimes can be determined. A new start The printing process is then based on this new one Basic time performed.

Figure 2 shows the timing of the just described Process. Time is t as the abscissa and is ordinate the speed P of the paper web 14 is plotted. To a At time T0, the paper web 14 is at rest, and the first character generator 24 begins, the four printed pages So1 to So4 to write on the first photoconductor tape 22. The second character generator 38 begins at a later time T1 four pages Su1 to Su4 on the second photoconductor belt 36 to write because the bottom time for the second Printing unit 12 is smaller than that for the first printing unit 10. The paper web is in an area B1 up to a point in time T2 14 at rest. Then in an area B2 up to a point in time T3 accelerates it to its final speed.

In an area B3, the pages So1 to So4 on the second transfer location 32 and the pages Su1 to Su4 on the fourth transfer point 46 is printed onto the paper web 14. If the controller does a deviation of the measured runtime from the target time, the printing operation becomes too interrupted at a time T4. In a range B4 up to At a time T5 the paper web 14 is stopped and so far withdrawn that with a new start a new one Print page in the designated area of the next unprinted Form can be reprinted.

The controller has during the process just described determines the new basic time and leaves the first character generator 24 begin at a time T6, four more pages To write So5 to So8 on the first photoconductor tape. To a the second character generator also begins at a later time T7 38, four more pages Su5 to Su8 on the second To write photoconductor tape 36.

Depending on the new base time, the paper web stays in one Area B5 is at rest until a time T8 and is in an area B6 accelerated again to its final speed. From time T9, pages So5 to So8 at the second transfer location 32 and pages Su5 to Su8 the fourth transfer printing point 46 in an area B7 onto the paper web 14 reprinted.

Figure 3 shows a second embodiment of an electrographic Printing device with a first printing unit 50 and with a second printing unit 52 similar to the first printing unit 10 and the second printing unit 12 of the first embodiment in Figure 1. The same elements have the same Reference signs as there. Instead of the first developer station 26 here are five developer stations 26a to 26e on the first one Arranged photoconductor belt 22, and instead of the second developer station 40 are also five developer stations here 40a to 40e arranged on the second photoconductor belt 36.

On the first and on the second transfer belt 30, 44 is in each case a mirror plate not shown as a brand firmly attached. To track the passage of the brand are a first reflex light barrier 54 and a second reflex light barrier 56 on the first transfer belt 30 and on second transfer belt 44 arranged.

The printing process corresponds to the second embodiment that of the first embodiment. In addition, at the second embodiment but in the operating mode "collection mode" a multicolored printed image on the paper web 14 be generated. This collection mode is in detail in the WO 98/39691. The sequence of such a collection mode is only explained for the first printing unit 50 in the following. The same applies to the second printing unit 52.

The transport of the paper web 14 is stopped and so far withdrawn that when starting the paper transport again at the second transfer location 32 to the following unprinted form can be printed on the paper web 14 can. From the first character generator 24 at a first Circulation of the first photoconductor tape 22 four latent images correspond to four printed pages generated on this. This four latent images are shared with the developer station 26a Colored toner in a first color. At the first transfer location 28 these four toner images become the first Transfer the color to the first transfer belt 30.

At the beginning of the collection mode, the first transfer belt 30 is turned on the second transfer printing point 32 is pivoted away from the paper web 14, thus the toner images as they pass the paper web 14 do not smudge or smear them. The first Reflex light barrier 54 detects the mark on the first Transfer belt 30 and gives according to their detection state a signal to a controller. The control is similar to the first embodiment, in FIG. 3 but not shown. It determines the from the signals Orbital period of the brand and forms an average. The first photoconductor belt 22 and the first transfer belt 30 run at the same, constant speed around, and out of Orbital period of the brand is determined when the first character generator 24 must begin, four more latent Images corresponding to four more printed pages on the first To produce photoconductor tape 22 so that they are congruent the four toner images are printed on the first transfer belt 30 become.

The first character generator 24 starts at the specified one Time with it in a second round of the first photoconductor belt 22 further four latent images corresponding to four to generate further printed pages on the first photoconductor belt 22. From the developer station 26b, these four latent ones Images colored with toner in a second color and at the first transfer printing point 28 onto the first transfer belt 30 congruent to the four toner images with the first color transfer-printed.

Similarly, a third, a fourth and a fifth circulation of the first photoconductor belt 22 each four further latent images of the generates the first character generator 24 on the photoconductor belt 22, from the developer stations 26c, 26d, 26e with toner one third, fourth and fifth colors and at the first transfer location 28 congruent to the four Toner images with the first and second color on the first Transfer ribbon 30 can be re-printed.

This procedure can create multi-color toner images in the collecting mode congruent on the first transfer belt 30 be reprinted. Then the first transfer belt 30 again at the second transfer printing point 32 to the paper web 14 pivoted, and the paper transport is started again in such a way that the four multi-colored congruent on the first Transfer ribbon 30 pages printed on the desired Position on the paper web 14 can be printed. The Collection mode is now finished and you can enter one below new collection mode started or continuously in one Color continues to be printed.

Parallel to the collection mode of the first printing unit 10 can the second printing unit 52 execute a similar collecting mode. There can also be a different number of developer stations each Photoconductor tape can be used.

FIG. 4 shows a sequence in the collecting mode in the exemplary embodiment according to FIG. 3. Time t is plotted as the abscissa and speed P of the paper web 14 is plotted as the ordinate. Similar to FIG. 2, the first character generator 24 begins at a time T0 to generate five printed pages as latent images on the first photoconductor belt 22. The collection mode is then started, in which during the time T _TF1 , which the first transfer belt 30 requires for one revolution, four latent images corresponding to four printed pages are generated by the first character generator 24 on the first photoconductor belt 22 and by one of the developer stations, for example the developer station 26b, can be colored with red toner.

In a second pass, a latent image on the photoconductor tape 22 generated and e.g. from the developer station 26c colored with green toner because only the fourth side should contain green, and be in a third pass again four latent images corresponding to four printed pages and from the developer station 26c with black toner inked.

At a point in time T1 after the point in time T0, the second character generator 38 also begins to generate five latent images on the second photoconductor belt 36. Subsequently, the second printing unit 12 likewise begins a collection mode, two latent images being generated during the first passage of the second transfer belt 44 during the time T _TF2 , which the developer station 40b colors with green toner. In a second run, two and in a third run four latent images are generated, each during the time T _TF2, which are colored by the developer station 40a or 40c with red or with black toner.

Similar to Figure 2, from time T2 to time T3 accelerates the paper web to its final speed. The first five toner images are then each in area B8 at the second or fourth transfer printing point 32, 46 printed on the paper web 14. In area B9 are the first and the second transfer belt 30, 44 from the paper web 14 swung away and it takes place on the second or fourth Transfer printing point 32, 46 no transfer printing of toner images the paper web 14. This is between the times T4 and T5 withdrawn and then remains in until T8 Quiet. The paper web 14 is opened again up to the time T9 their top speed accelerates, and the transfer belts 30, 44 are pivoted back onto the paper web 14.

In area B10 they are set to Transfer ribbons 30, 44 reprinted toner images at the transfer locations 32, 46 printed on the paper web 14. In connection it can be printed in one color without interruption become. In FIG. 4 there are five until time T10 other printed pages are reprinted with black toner. After that the paper web is stopped and pulled back.

This means short-term synchronous fluctuations in the photoconductor tapes 22, 36 and the transfer belts 30, 44 as low as possible fail and have little impact on print quality the length of each band is one Multiples of the size of the rolls on which the tapes each to run.

The two exemplary embodiments presented can be also combine. In this case there is a printing device available with precise at high speed a form can be printed. If necessary, this can Printing can also be done in multiple colors.

In the illustrated embodiments, the carrier material a carrier tape in the form of a continuous paper web 14 used. However, the invention is also in Printing devices can be used in which as a carrier material Cut sheets can be used. Instead of the photoconductor tape 22, 36, the use of a photoconductor drum is also possible. Lich.

The printing device described above is narrow Connection with the German patent application 198 56 146.6.

LIST OF REFERENCE NUMBERS

10

first printing unit

12

second printing unit

14

paper web

16

capstan

18

fuser

20

cooling device

22

first photoconductor band

24

first character generator

26

first developer station

26a to 26e

xEntwicklerstation

28

first transfer location

30

first transfer belt

32

second transfer point

34

first reflex light barrier

36

second photoconductor tape

38

second character generator

40

second developer station

40a to 40e

developer station

42

third transfer location

44

second transfer belt

46

fourth transfer point

48

second reflex light barrier

50

first printing unit

52

second printing unit

54

first reflex light barrier

56

second reflex light barrier

Claims (24)

1. Electrographic printer device with at least one printing unit (10, 12) having a toner image carrier on whose circumferential surface toner can be applied according to an image-like distribution,
   wherein the toner image carrier has a photoconductor (22, 36), whose outer circumferential surface can be charged with a latent charge image, and a transfer band (30, 44) onto which the toner present on the photoconductor (22, 36) can be transferred at a first transfer printing location (28, 42),
   means are provided by which a carrier material (14) is conducted past the transfer band (30, 44) such that the toner arranged thereon can be transferred onto the carrier material (14) at a second transfer printing location (32, 46),
   a printing mechanism for generating the toner image and that prints at least one mark onto the photoconductor (22, 36) is arranged along a circumferential section of the photoconductor (22, 36),
   at least one sensor (34, 48) that acquires the passing of the mark is arranged at the transfer band (30, 44),
   a controller determines the transit time of the mark from the printing time of the printing mechanism up to the acquisition time at the sensor (34, 48), and
   depending on the transit time influences the transport of the carrier material (14) in controlling fashion.
2. Printer device according to claim 1, wherein the controller compares the transit time with a predetermined desired value and generates a signal if this value is exceeded or fallen below.
3. Printer device according to claim 2, wherein the controller interrupts the operation of the printer device dependent on the signal.
4. Printer device according to claim 2 or 3, wherein the controller determines in a comparative measuring operation the base time which the toner image applied by the printer device requires in order to be transfer-printed at the second transfer printing location (32, 46) and determines the desired time on the basis of the base time.
5. Printer device according to claim 4, wherein the controller re-determines the base time upon occurrence of the signal.
6. Printer device according to one of the preceding claims, wherein the sensor (34, 48) is arranged in the region of the second transfer printing location (32, 46).
7. Printer device according to one of the preceding claims, wherein a reflex sensor (34, 48) that acquires the passing of the toner mark is provided as a sensor.
8. Printer device according to one of the preceding claims, wherein the printer device has at least one image generating unit (24, 38) for generating a latent charge image on the photoconductor band (22, 36) and has at least one developer station (26, 40) that inks the charge image with toner.
9. Printer device according to one of the preceding claims, wherein a continuous paper web (14) or single sheet material is provided as a carrier material.
10. Printer device according to one of the preceding claims, wherein the photoconductor is a photoconductor drum or a photoconductor band (22, 36).
11. Printer device according to one of the preceding claims, wherein a second (12) printing unit for generating a toner image on that side of the carrier material (14) facing away from the first printing unit (10) is arranged such that a duplex printing is possible.
12. Electrographic printer device with at least one printing unit (50, 52) having a toner image carrier on whose circumferential surface toner can be applied according to an image-like distribution,
    wherein the toner image carrier has a photoconductor (22, 36) whose outer circumferential surface can be charged with a latent charge image, and a transfer band (30, 44) onto which the toner present on the photoconductor (22, 36) can be transferred at a first transfer printing location (28, 42),
    means are provided by which a carrier material (14) is conducted past the transfer band (30, 44) such that the toner arranged thereon can be transferred onto the carrier material (14) at a second transfer printing location (32, 46),
    a printing mechanism for generating the toner image is arranged along a circumferential section of the photoconductor (22, 36),
    at least one mark is arranged on the transfer band (30, 44),
    at least one sensor (54, 56) that acquires the passing of the mark is arranged at the transfer band (30, 44),
    a controller determines the revolution time of the mark on the transfer band (30, 44), and
    depending on the revolution time, influences the printing operation effected by the printer device in controlling fashion.
13. Printer device according to claim 12, wherein the controller determines the time between the application of two successive toner images onto the photoconductor (22, 36) on the basis of the revolution time.
14. Printer device according to claim 12 or 13, wherein the controller determines the revolution time in a comparative measuring operation.
15. Printer device according to one of the claims 12 to 14, wherein the printer device has at least one image generating unit (24, 38) for generating a latent charge image on the photoconductor (22, 36) and at least one developer station (26a to 26e, 40a to 40e) that inks the charge image with toner.
16. Printer device according to one of the claims 12 to 15, wherein means are provided by which the transfer band (30, 44) is repeatedly conducted past the first transfer printing location (28, 42), and in that, in a collecting mode, a toner image is transferred onto the transfer band (30, 44) onto the previous toner image at every renewed passage.
17. Printer device according to claim 16, wherein means are provided by which the transfer band (30, 44) is pivoted away from the carrier material (14) at every renewed passage.
18. Printer device according to claim 16 or 17, wherein the controller sets the time between the application of two successive toner images onto the photoconductor (22, 36) on the basis of the revolution time such that they are congruently transfer-printed at the first transfer printing location (28, 42) upon passage of the transfer band (30, 44).
19. Printer device according to claim 18, wherein means are provided by which two successive toner images are respectively inked with toner by a different developer station (26a to 26e, 40a to 40e).
20. Printer device according to one of the claims 12 to 19, wherein the at least one mark is permanently arranged on the transfer band (30, 44).
21. Printer device according to one of the claims 12 to 20, wherein a reflex sensor (54, 56) that acquires the passing of the mark is provided as a sensor.
22. Printer device according to one of the claims 12 to 21, wherein a continuous paper web (14) or single sheet material is provided as a carrier material.
23. Printer device according to one of the claims 12 to 22, wherein the photoconductor is a photoconductor drum or a photoconductor band (22, 36).
24. Printer device according to one of the claims 12 to 23, wherein a second printing unit (52) for generating a toner image on that side of the carrier material (14) facing away from the first printing unit (50) is provided such that a duplex printing is possible.

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