EP0937282B1 - Printer with two printing units and pairs of transport rollers driven by step motors - Google Patents

Abstract

Disclosed is a printer with two similar printing units (D1, D2) fed with sheetlike material via a common input section (28). Printed material is outputted via a common output section (52). Groups of transport rollers and individual transport rollers are driven by step motors.

Description

Printer with two printing units and driven by stepper motors Transport roller pairs

The invention relates to a device, in particular a printer or Copier, with a first electrographic printing unit, which prints an image pattern on a sheet material, with an input section over which the sheet material can be fed individually one after the other, and with an output section, over which the printed sheet-shaped material individually is output one after the other.

In a known high-performance printer with only one Printing unit, the individual printer components are accurate coordinated so that a very reliable operating condition is achieved with high printing performance. To the To increase printing performance even further, must be constructive Changes to these components are made, too leads to a high development effort and the probability of failure due to the redesign of the individual components elevated.

From US 5,208,640 a printer is known, the two has similar printing units, those to be printed Scrolls individually through a common input section can be fed in succession.

In a printer known from DE 38 18 982 C2 Transport roller pairs arranged in the transport path of the paper, Different pairs of transport rollers become common through a single or a few central drives Synchronous belt driven.

When transporting the sheet material it makes it necessary that pairs of transport rollers differ Have speeds or have to change their direction of rotation, so are the rollers of previous solutions Transport roller pairs driven by switchable couplings Service. Gearboxes were also installed in front of the transport rollers arranged to the speed and direction of rotation according to the required operating mode. Even before this Gearboxes had to be arranged with switchable clutches. It has now been shown that such switchable couplings have large tolerances in their switching times and that high accelerations result when these clutches be switched. Another disadvantage is that the drive belt for the synchronous drive of the transport rollers are sometimes very long. The known solution is therefore very complex and has low operational reliability.

It is an object of the invention, a device of the aforementioned Specify the type of transport system for sheet-shaped Material allows a variety of operating modes of the device and that can be implemented with little effort.

This object is solved by the features of claim 1.

In the device according to the invention two are essentially similarly designed printing units are used. The components for these printing units, e.g. the electronic control, the Developer units, the toner supply and discharge devices etc., can be kept almost unchanged. each Printing unit on its own therefore has a very high level of operational reliability. Both printing units use a common one Input section through which the sheet material is fed becomes. Both printing units also use one together Output section for discharging the printed sheet Material. This makes the new device very compact and can be produced with little effort. by virtue of the printing capacity of the two printing units is significantly increased.

In the invention are as drives in their direction of rotation reversible stepper motors are provided. These stepper motors can be set to the desired frequency by a predefined frequency RPM can be set, during startup and Decelerate the drive to be highly synchronous with others similar drives is guaranteed. Different powered Transport rollers are grouped together which are driven by a single stepper motor. The Group formation leads to a reduction in the construction effort with the flexibility to adjust certain Speed profiles continue to exist. Through the Use and arrangement of these drives are switching Clutches and gears are not required, increasing operational reliability increases and the hardware expenditure is small remains. The division into groups on the one hand and in individual drives inside the device on the other hand leads to the fact that a variety of paper runs can be realized to if one of the printing units fails, the remaining one other printing unit can still execute print jobs.

In the invention, cut sheets can be made on different Transport sections in the printer different speeds have, sometimes a multiple of the transfer speed be. This makes it possible to do the respective Cut sheet after and before transfer printing at a higher speed than to convey the transfer speed. This can increase the overall throughput in the printer and longer dwell times on a section of the route, e.g. due to the passage through a switch or one Turning device, due to high conveyor speeds be balanced again. Because of the high speed outside the printing units can also be ensured that the prescribed distances between issued Single sheets are adhered to and despite if necessary different paths of cut sheets in the printer the correct one Output sequence is observed.

According to one embodiment, it is provided that at several Pairs of transport rollers, preferably on each pair of transport rollers, a scanning device is arranged which the Passing a leading edge or a trailing edge of the signaling sheet material. Preferably contains this scanning device has two light barriers, one of which is in front the pair of transport rollers and the other behind the pair of transport rollers is arranged. Based on the signals from the scanner can be determined at any time where a single sheet is located. In addition, traffic jams in the Device can be recognized. Depending on the detection of a leading edge or a trailing edge of the single sheet is the respective Transport roller pair accelerated or decelerated. To this Way, the passage of the single sheet through the controller can be optimized and the printer can use the highest possible Print speed work without a paper jam can occur in the printer.

According to a development of the invention, there is a first transfer printing transport path for the first printing unit and a separate one second transfer printing transport route provided for the second printing unit. The transfer printing for both printing units takes place with the same Speed. Because each printing unit has its own transfer printing path can, if a printing unit fails sheet material further printed with the other printing unit become.

Another exemplary embodiment provides that the first transfer printing transport route and through the second transfer printing path a connecting channel are connected, through which leaf-shaped Material in one or both transport directions is eligible. These measures can cause printed material from the first printing unit to the second printing unit and from the second Printing unit to be fed to the first printing unit to it print. A return is therefore through the connecting channel created which the two printing units together connects, which enables diverse printing processes.

Another embodiment provides that the leaf-shaped Material during transport from the first transfer printing path to second transfer printing transport path is turned. In this way can each printing unit the front and also the back printing on a single sheet. If for the two printing units Developer stations with different colors used so there can be two on each side of the single sheet Image patterns can be printed with two different colors, i.e. it can do a so-called two-color duplex operation, too Called duplex color spot 3 operation can be realized.

Figur 1

schematisch den Aufbau eines Hochleistungsdruckers, bei dem die Erfindung verwirklicht ist,

Figur 2

schematisch die Betriebsart Simplexdruck mit dem unteren Druckwerk,

Figur 3

schematisch die Betriebsart Simplexdruck mit dem oberen Druckwerk,

Figur 4

die Betriebsart abwechselnder Simplexdruck,

Figur 5

die Betriebsart Duplexdruck,

Figur 6

die Betriebsart Zweifarben-Simpiexdruck,

Figur 7

schematisch die Betriebsart Zweifarben-Duplexdruck,

Figur 8

schematisch die Verteilung der Transportwalzenpaare im Drucker längs des Transportwegs der Einzelbiätrer,

Figuren 9 bis 12

den Papierlauf im Drucker für verschiedene Betriebsarten.

Exemplary embodiments of the invention are explained below with reference to the drawing. It shows:

Figure 1

schematically the structure of a high-performance printer in which the invention is implemented,

Figure 2

schematically the operating mode simplex printing with the lower printing unit,

Figure 3

schematically the operating mode simplex printing with the upper printing unit,

Figure 4

the operating mode alternating simplex pressure,

Figure 5

the duplex printing mode,

Figure 6

the operating mode two-color simpex printing,

Figure 7

schematically the operating mode two-color duplex printing,

Figure 8

schematically the distribution of the pairs of transport rollers in the printer along the transport path of the individual feeder,

Figures 9 to 12

the paper run in the printer for different operating modes.

A high-performance printer 10 is shown in FIG for fast printing of single sheets of paper. The high performance printer 10 includes a first, lower one Printing unit D1 and a second, upper printing unit D2. Both Printing units D1, D2 work according to the known electrographic Process with the same transfer printing speed. The Fixing devices are connected downstream of printing units D1, D2, schematically in Figure 1 by two pairs of rollers 12, 14th are indicated. A paper board is attached to the high-performance printer 10 16 connected, the multiple storage container 18th up to 24 with single sheets and an external paper input channel 26 contains, via which single sheets are fed from the outside can be. Single sheets are transferred via a transport channel fed to an input section 28. On the output side is to High-performance printer 10 connected to a paper output 30, which contains a plurality of output containers 32 to 36. Furthermore are two output channels 38, 40 are provided, via the single sheets can be issued to processing stations. The high-performance printer 10 gives the printed single sheets via the output section 42.

Transport routes are located inside the high-performance printer 10 arranged for the transport of the single sheets through which different operating modes of the high-performance printer become. The printing units D1, D2 are transfer printing transport routes 44, 46 assigned, each by drives are set so that the single sheets fed to the Printing units D1, D2 have their transfer printing speed. Both Transfer printing transport paths 44, 46 are via a connecting channel 48 connected to each other. The transport route around the first Printing unit D1 is in a ring through a feed channel 50 added, via which also single sheets from the input section 28 can be fed to the second transfer printing transport path 46. The transport route for the second printing unit D2 is similar Supplemented into a ring by a discharge channel 52, over the single sheets printed by the printing unit D1 to the output section 42 can be supplied.

Between the input section 28, the first transfer printing transport path 44 and the feed channel 50 is a first switch W1 arranged, which enables cut sheets from the input section 28 optionally the first transfer printing transport path 44 or be fed to the feed channel 50. Another variant is that on the feed channel 59 in the direction the switch W1 transported single sheets on the first transfer printing path 44 can be supplied.

There are also a second switch W2 and a third switch W3 arranged at the ends of the connecting channel 48 and connect the adjacent transport routes 44, 52 or 46, 50. A fourth turnout W4 is nearby of the output section 42 and connects the adjacent ones Transport routes. The paper output 30 contains a fifth switch W5, which works as a turning device. Furthermore is still to point to a control device 54, which via a Soft W6 reject single sheets are fed.

Due to the arrangement described in Figure 1, various Operating modes of the high-performance printer 10 realized become. In the following Figures 2 to 7 are the different Operating modes shown schematically. The respective The promotion of single sheets is illustrated by arrows.

FIG. 2 shows schematically the simplex printing with only one Printing unit shown. With this simplex print only one Printed on one side of a single sheet. The single sheet arrives via the input section 28 and the corresponding switched Switch W1 along arrow P1 to the first transfer printing path 44 and is printed on the printing unit D1. Then will the single sheet along the discharge channel 52 (arrow P2) the output section 42 is output to the paper output 30 (Arrow P3).

Figure 3 shows the simplex printing with the upper, second printing unit D2. The single sheet is transported via the Feed channel 50 (arrow P4), the second transfer printing transport path (Arrow P5) to paper output 30 (arrow P6).

With alternating simplex printing with increased printing performance 28 single sheets with at least the double transfer speed of the printing units D1, D2 fed. Figure 4 shows schematically the transport of the Single sheets. The switch W1 leads alternately to the feed channel 50 or the first transfer printing path 44 single sheets to (arrows P7, P8). The single sheets are on their transport up to the printing units D1, D2 on transfer printing speed braked, there each printed on the front and then further promoted to switch W4. With this further funding according to the arrows P9, P10 the single sheets accelerated to at least twice the transfer speed, so that they over at the common output section the switch W4 issued at a distance from each other and in the Paper output 30 in sequence with at least double Transfer printing speed transported according to arrow P11 can be.

In the so-called operating mode "alternating simplex printing" is therefore provided according to the invention that in the paper input 16 the single sheets for the input section 28 with at least twice the transfer speed of the printing units D1, D2 be fed. In the paper edition 30, too Single sheets also at least twice the speed promoted and filed. Through these measures meet the single sheets at the common input section 28 and at the common output section 42 without that a collision of single sheets and consequently a paper jam can occur. The transport routes are preferred for the single sheets fed to the first printing unit D1 and the single sheets fed to the second printing unit D2 are symmetrical designed or at least the same length, so that on both Transport routes the single sheets with the same speed profile can be slowed down and accelerated. This makes it possible to have the necessary for transportation Build drives and devices in the same way. Farther it is possible to use similar controls.

Figure 5 shows schematically the duplex printing operation in which the single sheets are printed on both sides. The input section 28 single sheets are fed by the first switch W1 fed to the first transfer printing transport path 44 (Arrow P13). After printing by the printing unit D1 the respective single sheet a turning distance according to the arrow P14 conveyed beyond the turnout W2. This turning range is part of the discharge channel 52. Then the conveying direction reversed according to arrow P15, and the switch W2 conducts then the single sheet according to arrow P16 in the connection channel 48. The single sheet is then in the turnout W3 Direction of arrow P17 to the second transfer printing path 46 diverted. The printing unit D2 is therefore not yet printed Back of the single sheet fed for printing. Then cut the single sheets according to arrow P18 Soft W4 fed and into the paper output 30 along the Arrow P19 transported. Because the cut sheet in this condition is transported with its back up, it is in front filing in compartments 32 to 36. For this serves the turnout W5. The single sheet is first of all by the Switch W5 in the direction of arrow P20 for a predetermined one Turning range led. Then the transport direction is according to the arrow P21 reversed and the switch W5 promotes the single sheet in the direction of arrow P22, whereupon it is in the storage compartments 32 to 36 is stored correctly.

As can be seen, the switch W2 works as a turning device, around the printing unit D2 the back of the single sheet supply. Alternatively, the turnout W3 can also be used be used. The single sheet leaving the printing unit D1 is then on the switch W2, the connecting channel 48th the turnout W3 and then for a short turning distance the feed channel 50 in the direction of the switch W1. Subsequently the transport direction is reversed and the switch W3 directs the single sheet in the direction of the printing unit D2 with its back up.

FIG. 6 schematically shows a further operating mode, the two-color simplex printing, where the front of a single sheet printed with two image samples of different colors becomes. The two printing units D1, D2 print different image patterns Colour. In the above-mentioned operating mode two-color simplex printing the single sheet is turned over to the switch W1 Printing unit D1 fed (arrow P25). Then that will Single sheet over the switch W2 the connecting channel 48 without Turn and then fed to the printing unit D2 via the switch W3 (Arrows P26, P27). The printing unit D2 prints the front with a different color from the printing unit D1 Colour. Then the single sheet is on the switch W4 output to paper output 30 (arrow P28).

Figure 7 shows schematically the transport route of a single sheet in the two-color duplex printing mode, in which the Front and back of a single sheet with picture patterns different colors can be printed. requirement for this is that the printing units D1 and D2 have different colors Print images. For two-color printing on the front is the same as in the two-color simplex printing mode proceeded according to Figure 6. Arrows P25, P26, P27 and P28 illustrate the transport route. Then the cut sheet again fed to the printing unit D1. The arrows P29 up to P36 illustrate the transport path of the single sheet for printing on the back. So that this back of the printing unit D1 is fed must on the transport route between the Printing unit D2 and printing unit D1 turned the single sheet become. This turning can e.g. on the turnout W4, the turnout W2 or the switch W3. In a preferred embodiment the invention, the turning takes place with the help of Turnout W4, i.e. the single sheet is initially for a short Then transported turning path towards the turnout W5 the transport direction reversed and the single sheet in the direction the switch W2 further promoted. After transportation to the Paper output 30 according to arrow P36 is another Turn through the turnout W5 and then the right side Storage of the double-sided printed with two color images each Single sheet.

An alternative transport of the single sheet through the High-performance printer 10 to implement the operating mode Two-color duplex printing can be done in the following way First, the cut sheet is fed from the input section 28 the switch W1 fed to the printing unit D1, its front printed and then over turnouts W2 and W3 headed briefly towards the turnout W1. After passing the switch W3 becomes the transport direction in the direction Printing unit D2 changed and the single sheet on the transfer printing transport route 46 funded. The switch W3 thus serves as a turning station. At the printing unit D2, the back of the Single sheet printed. Then the single sheet is over the Switches W4, W2, W3 and W1 again fed to the first printing unit D1, to now print on the back. The single sheet must be used for this. This is done on switch W4, being conveyed briefly towards switch W5, the direction of transport reversed and in the direction of turnout W2 Condition is transported. After printing on the back of the single sheet in the printing unit D1 is the single sheet the switches W2 and W3 fed to the printing unit D2, it is turned. Now the front side of the printing unit D2 printed. Then the single sheet over the switch W4 led to storage compartments 32 to 36. Now that it's in the correct position, i.e. upside down in the tray 30 arrives, it does not have to be turned through the turnout W5 again become.

Figure 8 shows schematically the possible transport routes Single sheets in the high-performance printer 10. The different Transport sections 44, 46, 48, 50, 52 contain pairs of transport rollers T31 to T65 as shown, except are the elements T40 and T60, which are the printing units D1 and D2 relate to elements T43 and T63, which Fixing roller pairs of the downstream of the printing units D1, D2 Affect fuser stations. In addition, they are Transport roller pairs T30 and T48 with assigned stepper motors M30 and M48 to mention the turnouts W1 and W4 belong. Each pair of transport rollers T31 to T65 is at least assigned a light barrier L. The reference character L for each For reasons of clarity, the light barrier is shown in FIGS. 8 and the following figures only for the pairs of transport rollers T31 to T44 of the first transfer printing path 44 are shown. The light barriers L serve to pass the To detect the leading edge or the trailing edge of the single sheet, so that the controller stays at all times of the single sheet on the different transport routes knows and the respective pair of transport rollers T30 bis T65 accelerates according to the set operating mode or delayed. The different pairs of transport rollers T30 to T65 are slightly apart from each other Dimension of the single sheet in the conveying direction. In the case a DIN A4 single sheet with a dimension in the conveying direction The appropriate distance between the pairs of transport rollers is 210 mm Adhere to T31 to T65 of approximately 200 mm.

As drives for the driven roller of the transport roller pairs T30 to T65 are reversible in their direction of rotation Stepper motors M30 to M65 are provided, their assignment to the Various pairs of transport rollers can be seen in FIG is. Certain pairs of transport rollers are grouped together and are each powered by a single stepper motor driven. So are the feed roller pairs in the feed channel 50 T51, T52, T53, T54 combined into a group that are driven by a single M51 stepper motor. The respective driven rollers of the pairs of transport rollers T51 to 54 are coupled together by toothed belts, whereby perfect synchronous operation is guaranteed.

The transport roller pairs are in the first transfer printing transport path 44 T31 and T32 are grouped together and are driven by the M31 stepper motor. In the connecting channel 48 are the transport roller pairs T49 and T50 to a group summarized, driven by the single stepper motor M49 are. In the second transfer printing transport path 46, each Transport roller pair T55, T56, T64, T65 by a separate Stepper motor M55, M56, M64, M65 driven. The discharge channel 52 contains the transport roller pairs T45, T46 and T47, which are grouped together by the tiny M45 stepper motor can be driven together.

It can thus be seen that 10 different pairs of transport rollers are combined into groups along the entire transport path within the high-performance printer, each of which is driven by a single stepping motor. The transport roller pairs of each group have the same speed at all times, this speed changing between v ₀ and 4 xv ₀ (v ₀ is the transfer printing speed of the printing units D1, D2) and in their direction. The following table shows the different transport roller pairs T30 to T65, which speeds can occur in addition to the basic speed v ₀ . Transport roller pairs Geschwindiakeiten; v ₀ and at times the listed speeds T30 2.5 xv ₀ T31; T32 2.5 xv ₀ T45; T46; T47 4 xv ₀ ; 2.2 xv ₀ backwards. T48 3 xv ₀ ; 4 xv ₀ ; 2.2 xv ₀ back T49; T50 2.2 xv ₀ ; 2.5 xv ₀ T51, T52; T53, T54 4 xv ₀ ; 2.5 xv ₀ ; 2.2 xv ₀ back T55 4 xv ₀ T65 4 xv ₀

Because the aforementioned speeds at different times occur during printing only guarantees Independence of the different stepper motors M30 to M65 high flexibility for the runs of the single sheets in different operating modes. As mentioned, the transport roller pairs are T30 to T65 directly with the M30 stepper motors connected to M65, so that switching clutches are not required can.

The following Figures 9 to 12 show schematically the run of single sheets in the realization of different Operating modes of the high performance printer 10. In Figure 9 is the duplex operation shown, in which the front and the Back of the single sheets through the printing unit D1 or the Printing unit D2 are printed, the pass is based on the solid line 60 provided with directional arrows clearly. When turning on the turnout W3, the single sheet is included its front edge to the light barrier of the pair of transport rollers T52 led. Then the direction of rotation is reversed and the single sheet is fed via the switch W3 to the printing unit D2.

Figure 10 shows schematically the run in the operating mode Two-color duplex printing using line 60, the single sheets twice passed the printing units D1 and D2 become. The single sheets are turned in the switch W4, as illustrated by line 60.

FIG. 11 shows duplex printing with only one printing unit D1. The passage of the single sheets is based on line 60 clear. The single sheets are turned on the switch W2.

FIG. 12 shows the passage of single sheets along the lines 60a, 60b in the operating mode alternative simplex printing, in which single sheets are alternately fed to the printing units D1 and D2 for printing on the respective front side. The single sheets are fed at a speed 2.5 times over the pair of transport rollers 30. At the switch W1, the individual sheets are divided into the first transfer printing path 44 and the feed channel 50, which opens into the second transfer printing path 46. The single sheets are transported further via the transport roller pairs 31, 32 at the speed 2.5 xv ₀ . The speed of the single sheet is then decelerated such that it is guided past the printing unit D1 at transfer printing speed v ₀ . After passing through the fixing station with the pair of transport rollers T43, the single sheet is accelerated to a high transport speed, for example 4 × v ₀ , in order to be output at high speed via the pair of transport rollers T48. In an analogous manner, the single sheets are conveyed on the feed channel 50 and the second transfer printing path 46.

By setting different speeds and different directions of rotation of the transport roller pairs T30 up to T65 it is in the different operating modes of the High-performance printer possible when passing through switches and different lengths of transport routes within the high-performance printer 10 again wasted time compensate so that in the output section 42, the single sheets are output in the order they appear in the input section 28 have been supplied. The accelerations and delays of the cut sheets on the different Transport routes are set in such a way that the predetermined distances between the individual sheets become. The required flexibility of speeds of the individual pairs of transport rollers T30 to T65 guaranteed by the stepper motors M30 to M65, which work clock-controlled, which creates exact funding routes let set.

Claims (18)

1. Apparatus, particular printer or copier, comprising a first electrographic printing unit (D1) that prints an image pattern on a sheet-shaped material,

   comprising an input section (28) via which the sheet-shaped material can be supplied individually in succession to a delivery channel (50),

   comprising an output section (42) over which the printed, sheet-shaped material is output from a discharge channel (52) individually in succession,

   whereby a turning device for the sheet-shaped material is provided,

   whereby an essentially identical second printing unit (D2) is provided in the apparatus (10), sheet-shaped material being suppliable thereto via the common input section (28),

   whereby the sheet-shaped material printed by the second printing unit (D2) is output via the common output section (42),

   whereby transport roller pairs (T30-T65) driven by drives (M30-M65) are arranged in the transport path (44, 46, 50, 52) for the sheet-shaped material from the input section (28) to the output section (4), said transport roller pairs having a spacing from one another slightly smaller than the dimension of the material in conveying direction,

   whereby the transport roller pairs (T30-T65) have different rotational speeds and conveying directions dependent on the operating mode of the apparatus,

   whereby stepping motors with reversible rotational sense or clock-controlled motors (M30-M65) are provided as drives,

   whereby predetermined, driven transport rollers are combined to form groups and are directly coupled to one another and are respectively driven by a single drive, whereby a first transfer printing transport path (44) along the first printing unit (D1) and a separate, second transfer printing transport path (46) along the second printing unit (D2) are provided,

   whereby the input section (28) contains a shunt (W1) that supplies the sheet-shaped material either to the first transfer printing transport path (44) or to the second transfer printing transport path (46),

   whereby the first transfer printing transport path (44) and the second transfer printing transport path (46) are connected by a connecting channel (48) through which sheet-shaped material can be conveyed in one or in both conveying directions,

   whereby a sensor means is arranged at a plurality of transport roller pairs, said sensor means signaling the passage of an edge of the sheet-shaped material, and

   whereby a predetermined transport roller pair is accelerated or retarded dependent on the signals of the sensor means.
2. Apparatus according to claim 1, characterized in that the shunt (W1) supplies sheet-shaped material to the first transfer printing transport path (44) and the second transfer printing transport path (46) in alternation.
3. Apparatus according to claim 1 or 2, characterized in that the connecting channel (48) contains two transport roller pairs (T49, T50) whose driven transport rollers are combined to form a group with a connecting channel stepping motor (M49).
4. Apparatus according to claim 3, characterized in that the connecting channel stepping motor (49) is operated, dependent on the operating mode, with the transfer printing speed v₀, essentially 2.2 times the transfer printing speed (v₀) and essentially 2.5 times the transfer printing speed (v₀).
5. Apparatus according to one of the preceding claims, characterized in that the turning means contains a shunt (W2, W3, W4); that, for being turned, the sheet-shaped material is first conducted past the shunt (W2, W3, W4) on a first transport path in a transport direction into a turning section (52, 50); in that, subsequently, the transport direction is reversed; and in that the shunt (W2, W3, W4) conveys the sheet-shaped material to a second transport path in the other transport direction.
6. Apparatus according to one of the preceding claims, characterized in that the delivery channel (50) contains four transport roller pairs (T51, T54) whose driven transport rollers are combined to a group with a delivery channel stepping motor (51).
7. Apparatus according to claim 6, characterized in that the delivery channel stepping motor (M51) is operated, dependent on the operating mode, with the transfer printing speed (v₀), essentially four times the transfer printing speed (v₀), essentially 2.5 times the transfer printing speed (v₀) and essentially 2.2 times the reverse transfer printing speed (v₀).
8. Apparatus according to one of the preceding claims characterized in that the discharge channel (52) contains three transport roller pairs (T45-T47) whose driven transport rollers are combined to a group with a discharge channel stepping motor (M45).
9. Apparatus according to claim 8, characterized in that the discharge channel stepping motor (M45) is operated, dependent on the operating mode, with the transfer printing speed (v₀), essentially for time transfer printing speed (v₀) and essentially 2.2 times the reverse transfer printing speed (v₀).
10. Apparatus according to one of the preceding claims, characterized in that the first transfer printing transport path (44) contains two transport roller pairs (T31, T32) in conveying direction following the input section (28), the driven transport rollers thereof being combined to a group with a first stepping motor (M31).
11. Apparatus according to claim 10, characterized in that the first stepping motor (M31) is operated, dependent on the operating mode, with the transfer printing speed (v₀) or essentially 2.5 times the transfer printing speed (v₀).
12. Apparatus according to one of the preceding claims, characterized in that the driven transport rollers of each and every group are connected to one another by toothed belts.
13. Apparatus according to one of the preceding claims, characterized in that the further transport roller pairs (T30, T36, T44, T55, T56, T64, T65, T48) not combined into groups are respectively separately driven by individual stepping motors (M30, M46, M44, M55, M56, M64, M65, M58).
14. Apparatus according to one of the preceding claims, characterized in that the first transfer printing transport path (44), the connecting channel (48) and a delivery channel (50) form a closed transport path, whereby the delivery channel can transport sheet-shaped material in both directions and supplies sheet-shaped material to the second transfer printing transport path.
15. Apparatus according to one of the preceding claims, characterized in that the second transfer printing transport path (46), the connecting channel (48) and a discharge channel (52) for sheet-shaped material form a closed transport path, whereby the discharge channel (52) can convey sheet-shaped material in both directions and connects the first transfer printing transport path (44) to the output section (42).
16. Apparatus according to one of the preceding claims, characterized in that the input section (28) contains a first shunt (W1); in that a second shunt (W2) is arranged at the junction between first transfer printing transport path (44) and connecting channel (48) and discharge channel (52); in that a third shunt (W3) is arranged at the junction between connecting channel (48), second transfer printing transport path (46) and delivery channel (50); and in that a fourth shunt (W4) is arranged at the junction between second transfer printing transport path (46) and discharge channel (52).
17. Apparatus according to one of the preceding claims, characterized in that a sensor means is arranged at every transport roller pair.
18. Apparatus according to one of the preceding claims, characterized in that the sensor means contains two light barriers (L) for recognizing the leading edge and the trailing edge.

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