EP0697634B1 - Continuous print web inverter - Google Patents

Description

The invention relates to a turning device for tape-shaped recording media arranged within an electrographic printing device.

Modern electrographic printing systems are increasingly expected to offer a high level of economic customer benefit and a wide range of flexibility. The effective use of substrates as well as the flexible design of the print information play a major role here.

Wherever a high level of device availability with a large print volume and a wide range of substrates is required, continuous processing (FAN-FOLD) electrographic printing systems that print a tape-shaped recording medium on one side have become established. However, these printing systems have the disadvantage that a change between single-sided and double-sided printing is not possible. This leads to an economically unfavorable situation for the user as well as a contradiction to the contemporary requirements for the use of raw materials. This means that many customer-specific applications that absolutely require double-sided printing (brochures, books, etc.) cannot be satisfied, especially since electrographic high-performance printers are particularly economical if they are operated as uninterrupted as possible.

To produce multicolor and reverse side printing with continuous-paper electrographic printing devices, it is known from EP-B1-01 54 695 to operate two continuous paper printers in succession, the paper printed in the first printer being turned over and subsequently printed in the second printer on the second side .

The effort is considerable due to the second printer required.

From the literature reference IBM Technical Disclosure Bulletin Vol. 22, No. 6 of November 1979, pages 2465 to 2466, an electrophotographic printing device for printing on tape-shaped recording media is known, with which it is possible to print on both sides of the recording medium. For this purpose, the recording medium is pulled off a stack of supplies, fed to a transfer printing station and provided with toner images on one side. After fixing, the recording medium is turned using a turning device made of deflecting rods and fed again to the transfer printing station. After the back of the recording medium has been printed with toner images, it is fixed again in the fixing station.

This old literature basically describes duplex printing with continuous recording media. However, the proposal never resulted in a product. Furthermore, the described electrographic printing device is only suitable for printing on both sides of the record carrier. A change of operating mode is not planned. The turning device made of deflecting rods requires manual threading of the recording medium, and the type of arrangement of the deflecting rods also requires a large amount of installation space.

The aim of the invention is therefore to provide a turning device for tape-shaped recording media which enables automatic threading of the recording media.

Another object of the invention is to design the turning device in such a way that it can be arranged in a user-friendly manner in an electrographic printing device with which printing on one and both sides of a tape-shaped recording medium is possible.

These objects of the invention are achieved according to the features of the first claim.

Advantageous embodiments are characterized in the dependent claims.

Deflection elements arranged in the form of the letter W in conjunction with a motor-driven rotating gripping element enable a compact and reliable construction of a turning device with automatic threading of the record carrier.

The turning device can be used between two separate devices as well as integrated in one device. Due to its compact design as a self-supporting, slidably suspended structural unit, it is particularly suitable for integrated arrangement in multifunctional electrographic printing systems which, due to their structure, can print on continuous paper both on one side and on both sides, in one color or multi-color.

In such a multifunctional electrographic printing system, the transfer printing station and the fixing station have a usable width of at least twice the bandwidth of the recording medium, with each of these units being run through twice in duplex mode by the recording medium, in parallel next to one another. The turning device is arranged downstream of the fixing station and can be coupled to the transfer station via the paper outlet channel. The turning device thus has two tasks: on the one hand it rotates the recording medium by 180 °, on the other hand it displaces the recording medium running out of the fusing station laterally by a recording medium width so that the subsequent transfer printing station and again the fusing station can be run through in parallel.

The use of deflecting elements in the form of hollow rods, which are connected to one another, enables integrated air guidance in order to produce a friction-reducing air cushion in the area of the sliding surfaces of the deflecting elements.

When the assembly is pushed into the printer, the electrical and pneumatic supply to the turner is automatically connected.

In order to ensure the accessibility of the turner in the event of paper flow disturbances and to be able to clean the turner easily, the paper guide surfaces are designed to be pivotable, in particular in the region of the deflection elements.

It is also expedient to use a conveyor belt which is guided around the outer turning elements and has a friction lining on its inside as the threading element. In the operating state of the printing device with the recording medium inserted in the turning device, the friction lining is positioned between the inclined deflection elements in such a way that it is out of engagement with the recording medium. In the area of the lateral deflection elements, the conveyor belt is guided at a distance around their sliding surfaces, whereas the recording medium slides along the sliding surfaces. The position of the record carrier relative to the friction lining thus changes prematurely. It is thus possible, at the end of the threading process, to push the beginning of the recording medium far beyond the rear end of the friction lining into the paper exit channel, where it is gripped by paper transport elements.

Embodiments of the invention are shown in the drawings and are described in more detail below, for example. Show it

FIG. 1 shows a schematic illustration of an electrographic printing device for printing on tape-shaped recording media in duplex mode,

FIG. 2 shows a schematic sectional illustration of the same electrographic printing device,

FIG. 3 shows a schematic illustration of a turning device arranged in the electrographic printing device,

FIG. 4 shows a schematic illustration of the turning device arranged in the electrographic printing device in a side view,

FIG. 5 shows a schematic sectional illustration of the paper guide in the turning device along the section line C-C of FIG. 3,

FIG. 6 shows a schematic sectional illustration of the paper guide in the turning device along the section line B-B of FIG. 3,

FIG. 7 shows a schematic illustration of the paper guide in the area of the lateral reversing devices,

8 to 10 are schematic sectional representations of the threading process of the recording medium into the turning device along the section line A-A of FIG. 3,

11 to 15 are schematic representations of the threading process of the recording medium into the turning device, FIG. 16 shows a block diagram of a control arrangement for the turning device,

Figure 17 is a schematic representation of the turning device in the service position and

Figure 18 is a schematic representation of the turning device in the operating position.

An electrographic printing device for printing on tape-shaped recording media 10 of different bandwidth contains an electromotive-driven photoconductor drum as intermediate media 11. Instead of the photoconductor drum, however, a band-shaped intermediate carrier, e.g. use an OPC tape or a magneto-styli arrangement, e.g. is described in EP-B1-0 191 521. The various units for the electrophotographic process are grouped around the intermediate carrier 11. These are essentially: a charging device 12 in the form of a charging corotron for charging the intermediate carrier 11; a character generator 13 with 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 with the aid of a one- or two-component developer mixture; a transfer printing station 15, which extends over 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 development and transfer printing, a cleaning station 16 is provided with a cleaning brush integrated therein with the associated suction device and a discharge device 17. The intermediate carrier 11 is driven by an electric motor and moved in the direction of the arrow in printing operation.

Furthermore, the printing device contains a fixing station 18 which is arranged downstream of the transfer printing station 15 in the transport direction of the recording medium and which is designed as a thermal printing fixing station, with a heated fixing roller 19 Associated pressure roller 20, and guide rollers 21 arranged downstream of the fixing station, which serve, among other things, as output elements for a stacking device 22 for the recording medium 10. Instead of the fixing station shown, other fixing stations are also possible, for example with a heated or unheated inlet saddle or a cold fixing station. The tape-shaped recording medium 10 is made up, for example, as prefolded, continuous paper provided with edge perforations and is fed from a storage area 23 to the transfer station via feed rollers 24. However, it is also possible to feed a recording medium without edge perforations via a roll feed.

The transport of the record carrier is preferably carried out via a transport device 25 assigned to the transfer printing station 15 in the form of conveyor belts provided with pins which, guided by drive shafts 27, engage in the perforations on the edge of the record carrier 10. In the event that a transport-hole-free recording medium is used, an adapted transport device familiar to the person skilled in the art is to be provided which e.g. transported by friction, controlled by a control arrangement scanning synchronization marks. Furthermore, a turning device 28 is arranged in the housing area of the printing device between the storage area 23 and the fixing station 18, the function of which will be explained later and via which the recording medium is returned from the fixing station 18 to the transfer printing station 15.

The printing device is controlled by a printer controller, which is shown schematically here, with a central unit CPU, a page memory SP, which is subdivided into memory areas depending on the page, and a data control unit DC. All control units are connected to each other and to the units of the printing device via a BUS system.

The electrographic printing device is suitable for printing on recording media with different bandwidths. For this purpose, the intermediate carrier 11 (photoconductor drum) has a usable width which corresponds to the largest possible recording medium width (e.g. a format DIN A3 landscape). This width corresponds to twice the A4 bandwidth. It is thus possible to arrange two A4 recording medium widths alongside one another in the area of the transfer printing station 15. The fixing station 18 and the other electrophotographic units, such as developer station 14, character generator 13, cleaning station 16, are designed in accordance with this usable width. Adapting the width of the character generator 13 to different recording medium widths does not require any mechanical change to the character generator if, as in this case, an LED character generator is used with a large number of LEDs arranged in rows. An adaptation to the recording medium width used is carried out electronically by control.

In order to adapt the transport device 25 to different recording medium widths, the transport device can be designed to be width-adjustable. This can e.g. can be achieved in that the drive wheels, which carry the conveyor belts (nubbed belts) engaging in the perforations on the edge of the record carrier, are displaceably mounted on polygonal shafts.

If two narrow recording media are arranged and transported next to one another in the area of the transfer printing station 15, it is normally sufficient to provide a transport device only for the outer peripheral perforations. With an appropriate design, it is therefore possible to use the same conveyor belts for the wide record carrier and the two narrower record carriers without these having to be adjusted. Should it still be necessary to run the record carrier on both sides, separate transport elements can be arranged in the center for operation with two narrow recording media arranged next to one another, which engage in the perforations on the edge of the recording media. So that these transport elements do not interfere with operation with only one wide recording medium, they can be arranged such that they can be plugged in and plugged in or swiveled out, or it is possible to provide the drive wheels 27 of the transport device 25 with retractable pins and knobs.

The turning device 28 arranged in a return channel for narrow record carriers from the fixing station 18 to the transfer printing station 15 serves for rotating the record carrier from the front to the back. It is designed to be switchable depending on the operating mode and has an automatic threading device for the recording medium.

For double-sided monochrome printing of a narrow recording medium in duplex mode, as shown in FIG. 1, the narrow, for example A4-wide, recording medium is fed from the storage area 23 via the feed rollers 24 to the transfer station 15 and printed on its upper side with a front-side toner image. The front of the record carrier 10 is identified by solid transport arrows, the underside by dashed transport arrows. The recording medium with the front-side toner image is then fed to the fixing station 18 and the front-side toner image is fixed. Via the guide rollers 21, the recording medium is transported further to the turning device 28, the deflection contour of which is positioned in a turning position. In the turning device 28, the record carrier is turned with respect to its front and back and fed again via the feed rollers 24 to the transfer printing device 15 in such a way that its back can be provided with a back toner image. Then the recording medium is again fed to the fixing station 18 and the back toner image is fixed and then the recording media printed on both sides are stored in the stacking device 22.

Since the front and back toner images are generated at different times and printed on the recording medium, a corresponding data preparation via the printer control is necessary. For this purpose, the page memory SP contains storage areas VS for storing the front side image data and storage areas RS for storing the back side image data. The data preparation takes place via the data control device DC, the data starting from a data source (HOST), e.g. can be supplied to an external data memory via an interface of the data control device DC. The data of the individual pages to be printed are stored in the page memory SP, separately to the front VS and back RS in the corresponding memory areas. The call of the data is then time-controlled so that the desired front-back assignment of the toner images on the recording medium is achieved.

Turning device

The turning device 28 (FIG. 3) essentially contains four deflection elements arranged in the manner of the letter W, via which the recording medium 10 is guided starting from a paper inlet channel 30 to a paper outlet channel 31. Paper inlet channel 30 and paper outlet channel 31 are arranged side by side in one plane.

A recording medium 10 fed via the paper inlet channel 30 is first guided over a first oblique deflection device 32 which deflects the recording medium laterally. This consists of a hollow deflecting rod 33 or roller arranged at approximately 45 ° to the paper running direction. The first inclined deflection device 32 in the paper transport direction is followed by a first reversing device 34 with a Deflection element 35 in the form of a hollow profile for returning the recording medium 10 behind the paper channels to the area of a second reversing device 36 which is arranged approximately parallel to the first reversing device 34 and reverses the recording medium 10 again. This likewise has a deflection element 35 in the form of a hollow profile. Downstream of the second reversing device 36 is a second oblique deflecting device 37 deflecting the recording medium 10 into the paper outlet channel 31, with a hollow deflecting rod 33 or roller arranged at approximately 45 ° to the paper running direction.

Deflection rods 33 and deflection elements 35 have wear-resistant polished surfaces as deflection surfaces 38 (FIGS. 5, 6, 7) which serve as sliding surfaces for the recording medium 10 and which are encompassed at a distance from guide surfaces 40 forming a deflection channel 39. The guide surfaces 40 assigned to the deflecting rods 33 of the oblique deflecting devices 32 and 37 are part of hinged flaps 41 made of hollow profiles. They are shown in FIG. 3 in the operating position (solid line) and in the pivoting position (broken lines). The guide surfaces 40 of the deflection elements 35 consist of spring plates 42, which are arranged on the front and rear, swiveling housing flaps 43 of the turning device. The housing flaps 43 are shown in the swiveled position in FIG. 4 with broken lines.

In order to reduce the friction between the sliding surfaces and the recording medium in the region of the deflection points, the deflection surfaces 38 have air outlet openings 44 (FIGS. 5, 6, 7), via which an air cushion between the recording medium and the deflection surfaces can be generated, particularly when threading. The cavities of deflecting rods 33 and deflecting elements 35 are connected to one another and serve as air supply channels. A connection module 45 arranged in the receiving area for the turning device in the device is provided with the right-hand deflection element 35 for controlled feeding Blown air can be coupled via a blower 57. It also contains a plug for the electrical connection.

The turning device further contains a threading device for the recording medium 10 with a motor-driven gripping element which is guided around the reversing devices 34, 36 and has gripping means for the beginning of the recording medium, the beginning of the recording medium being detected in the area of the first oblique deflection device 32 for threading into the turning device and via the reversing devices 34 , 36 and the second inclined deflection device 37 is transported into the area of the paper outlet channel 31.

In the exemplary embodiment shown, the gripping element consists of an edge-perforated conveyor belt 46 which is guided about the reversing devices 34, 36 via guide axes 47. It is driven by a motor 48. A friction lining 49 (friction element) made of foam or silicone is arranged on the inside of the conveyor belt 46. Its length is dimensioned such that in the operating state of the turning device shown in FIG. 3, in which the friction element 49 is located between the oblique deflection devices 32, 37, the friction element 49 is out of engagement with the recording medium 10.

Around the reversing devices 34, 36 there is a recording medium circulation channel 50 with associated switches 51 for introducing and discharging the recording medium 10 in the area of the oblique deflection devices 32, 37. In principle, this results in a continuous guide channel for the recording medium 10 together with the deflection channels 39 the deflection elements 33, 35 from the paper inlet channel 30 to the paper outlet channel 31. The conveyor belt 46 is immersed in the channel sections of the recording medium circulation channel lying between the reversing devices 34, 36 and is guided there. The channel walls facing the friction lining 49 have roller elements 52 (FIGS. 3, 9) in the region of the conveyor belt 46 Reduction of the friction between the recording medium 10 and the wall surface. The recording medium 10 is clamped between the roller elements 52 and the friction lining 49 and thus safely transported through the friction lining 49.

In the area of the reversing devices 34, 36, the conveyor belt 46 is guided over a transport path (FIG. 7) which runs outside the deflection channel 39 as part of the recording medium circulation channel 50 and which is longer than the transport path of the beginning of the recording medium through the deflection channel 39. This changes in a leading manner, the position of the recording medium 10 relative to the friction lining 49 when circulating around the reversing devices 34, 36. Thus, at the end of the threading process, it is possible to push the beginning of the recording medium far into the paper outlet channel 31 via the rear end of the friction lining 49, where it starts from Paper transport elements 53 is detected. These paper transport elements 53 can consist of pivotable friction wheels or impact elements or tractors with transport slats. They are arranged in the region of the inclined deflection devices 32, 37 in the paper inlet channel 30 and in the paper outlet channel 31, specifically in such a way that they engage on the side of the recording medium 10 free of toner images. Furthermore, an additional motor-driven recording medium transport device in the form of paper transport rollers 54 is arranged downstream of the second inclined deflection device 37, which serves to feed the recording medium 10 to the return channel to the transfer printing station.

The turning device is controlled via a microprocessor-controlled threading control arrangement shown in FIG. 16, which can be part of the device control. It consists of the actual central control ZS containing a microprocessor. On the input side, this is connected to an optical sensor S2, which is arranged below the first oblique deflection device 32 and which records the start of the recording medium in the region of the first oblique deflection device 32 scans and with a sensor S1 arranged in the region of the first reversing device 34, which can be designed as a Hall sensor and which scans the position of the friction element 49 (friction lining) via a magnetic element. On the output side, the threading control arrangement is coupled to the blower for generating the blown air 56, the drives for the paper transport elements 53 and the paper transport rollers 54 and the conveyor belt drive 48. The threading control arrangement detects the start of the recording medium in the area of the first inclined deflection device 32 via the sensor S2, activates the conveyor belt drive 48 as a function thereof, and positions the friction lining 49 in a rest position depending on the position signal of the sensor S1 after threading the beginning of the recording medium into the paper outlet channel 31 in which it is out of engagement with the recording medium 10.

The turning device is designed as an independent, torsionally rigid structural unit and is mounted on telescopic rails 55 such that it can be pulled out in the device (FIGS. 17, 18). This means that all deflection elements are freely accessible in the event of paper flow disruptions and servicing.

Function of the turning device

To automatically thread the record carrier through the turning device, the blower for generating the blown air 56, the drives for the paper transport elements 53 and the paper transport rollers 54 are activated via the threading control arrangement ZS. The friction lining 49 is in the rest position shown in FIGS. 8 and 11 between the inclined deflecting elements 32, 37. The beginning of the tape entering through the paper inlet duct 30 is deflected in the deflecting duct 39 of the first inclined deflecting device 32 and detected by the sensor S2. As a result, the conveyor belt 46 is started. It detects the beginning of the belt (FIG. 12) via the friction lining 49 and transports it around the first reversing device 34 (Figures 9, 12). The beginning of the recording medium leads the friction lining 49 somewhat. Thereafter, the beginning of the recording medium revolves around the second reversing device 36 and again leads the friction lining 49 somewhat ahead (FIGS. 10, 13). With the rear end of the friction lining 49, the beginning of the recording medium is then pushed over the switch 51 through the second inclined deflection device 37 into the area of the paper transport element 53 (FIG. 14), gripped by it and transported into the area of the paper transport rollers 54 (FIG. 15) and from there to the transfer station. This ends the threading process and the friction lining is again out of engagement with the recording medium in the rest position (FIGS. 8, 11).

The paper inlet channel 30 of the turning device 28 is connected to a recording medium output channel 29 (FIG. 2) assigned to the fixing station 18, which has a usable width of at least twice the bandwidth of the recording medium 10, via paper transport elements 57. As a result, it is also possible to feed the recording medium 10 again with the required offset, without turning, to the transfer printing station 15 via the rollers 24 and thus to produce two-color overlaid color printing. For this purpose, the developer station 14 may have two separate developer areas 14/1, 14/2 for e.g. red and black toners.

In the illustrated embodiment, the gripping element with the gripping means consists of a conveyor belt 46 with a friction lining 49 arranged thereon. It is also possible to use a mechanical clamping element or a friction piece which is moved by means of traction means. Instead of the start-stop operation of the conveyor belt or the friction lining, the conveyor belt can also be moved continuously around the reversing devices in accordance with the recording medium transport speed, the friction lining remaining in constant engagement with the recording medium.

It should also be noted that the function of the paper inlet channel can also be carried out by the paper outlet channel and vice versa, that is to say the turning device can be operated in two transport directions.

Reference list

10 =

Record carrier

11 =

Intermediate beam

12 =

Charging device, charging corotron

13 =

LED character generator, imaging device

14 =

Developer station

14/1 =

Developer station first color (red)

14/2 =

Developer station second color (black)

15 =

Transfer station

16 =

Cleaning station

17 =

Unloading device, unloading corotron

18 =

Fuser

19 =

Fuser roller

20 =

Pressure roller

21 =

Leadership roles

22 =

Stacking device

23 =

Storage area

24 =

Feed rollers

25 =

Transport device

26 =

Conveyor belt

27 =

drive shaft

28 =

Deflection device

29 =

Media output channel

CPU =

Central unit

SP =

Page memory

DC =

Data control unit

BUS =

Data bus

VS =

Storage area front image

RS =

Storage area back image

HOST =

Data Source

E1, E2 =

Developer zones, developer areas

30 =

Paper inlet channel

31 =

Paper outlet channel

32 =

first inclined deflection device

33 =

Deflection bar, hollow bar

34 =

first reversing device

35 =

Deflection element, hollow profile

36 =

second reversing device

37 =

second inclined deflection device

38 =

Deflection surface

39 =

Deflection channel

40 =

Guide surfaces

41 =

Valves

42 =

Spring washers

43 =

Case flaps

44 =

Air outlet openings

45 =

Connection module

46 =

Conveyor belt

47 =

Leading axes

48 =

engine

49 =

Friction lining

50 =

Record carrier, circulation channel

51 =

Switches

52 =

Roll elements, paper rollers

53 =

Paper transport elements, tractor elements, swiveling friction wheels

54 =

Paper transport rollers, record carrier pulling device

55 =

Telescopic rails

ZS =

Central control unit, threading control arrangement

S2 =

Sensor, optical sensor

S1 =

Sensor, Hall sensor

56 =

Blower, compressed air generating device

57 =

Paper transport elements, paper transport device

Claims (16)

1. Inverter for recording media (10) in web form, having

   - a paper run-in channel (30) and a paper run-out channel (31), which are arranged next to each other;

   - a first obliquely deflecting device (32), laterally deflecting the recording medium (10) fed in via the paper run-in channel (30); characterized by:

   - a first reversing device (34), arranged downstream of the first obliquely deflecting device (32) in the paper transporting direction, for returning the recording medium (10) behind the paper channels into the region of a second reversing device (36), arranged approximately parallel to the first reversing device (34) and reversing the recording medium (10) anew;

   - a second obliquely deflecting device (37), arranged downstream of the second reversing device (36) and deflecting the recording medium (10) into the paper run-out channel (31), and

   - a threading device for the recording medium (10), having a gripping element (46) which is disposed around the reversing devices (34, 36), is driven by motor and has gripping means (49) for the beginning of the recording medium, in which arrangement, for threading into the inverter, the beginning of the recording medium is taken up in the region of the first obliquely deflecting device (32) and is transported via the reversing devices (34, 36) and the second obliquely deflecting device (37) into the region of the paper run-out channel (31).
2. Inverter according to Claim 1, having a gripping element which has a friction element (49).
3. Inverter according to Claim 2, having a transporting belt (46) which loops around the reversing devices and on the inner side of which the friction element (49) is arranged.
4. Inverter according to one of Claims 2 or 3, the length of the friction element (49) being dimensioned such that, in an operating position in which the friction element (49) is located between the obliquely deflecting devices (32, 37), the friction element (49) is out of engagement with the recording medium (10).
5. Inverter according to one of Claims 1 to 4, the obliquely deflecting devices and/or the reversing devices having deflecting surfaces (38) designed as sliding surfaces, which are enclosed by guiding surfaces (40, 41, 42) with a spacing forming a deflecting channel (39).
6. Inverter according to Claim 5, having guiding surfaces (40, 41, 42) designed such that they can be swivelled away.
7. Inverter according to one of Claims 5 or 6, having air-outlet openings (44) which are arranged in the region of the deflecting surfaces (38) and are connected to an air-supply system (56).
8. Inverter according to Claim 7, the obliquely deflecting devices (32, 37) and/or the reversing devices (34, 36) having as deflecting elements hollow bodies with deflecting surfaces, which can be coupled to one another for common air supply.
9. Inverter according to one of Claims 1 to 8, having a recording-medium bypass channel (50), which is disposed around the reversing devices (34, 36) and has assigned diverters (51) for directing the recording medium (10) in and out in the region of the obliquely deflecting devices (32, 37), the gripping element (46) being disposed at least in the channel sections of the recording-medium bypass channel (50) which lie between the reversing devices (34, 36).
10. Inverter according to one of Claims 1 to 9, the gripping element (46, 49) being disposed around the reversing devices (34, 36) over a transport path which is longer than the transport path of the recording medium, with the result that the beginning of the recording medium is ahead of the gripping element (46, 49) when running around the reversing devices (34, 36).
11. Inverter according to one of Claims 1 to 10, having paper-transporting elements (53) arranged in the paper run-in channel (30) and/or in the paper run-out channel (31) and feeding the beginning of the recording medium to the first obliquely deflecting device or receiving it from the second obliquely deflecting device.
12. Inverter according to Claim 11, having an additional recording-medium transporting device (54) arranged downstream of the second obliquely deflecting device (37).
13. Inverter according to one of Claims 1 to 12, having

    - a first sensor (S1), sensing the position of the gripping element (46, 49),

    - a second sensor (S2), scanning the recording medium (10) in the region of the first obliquely deflecting device (32), and

    - a threading-control arrangement (ZS), which is coupled to the sensors (S1, S2) and recording-medium transporting means, for threading the beginning of the recording medium senses the beginning of the recording medium in the region of the first obliquely deflecting device (32) by means of the second sensor (S2), in dependence thereon activates the threading device and, after threading through the beginning of the recording medium into the paper run-out channel (31), positions the gripping element (46, 49) in a rest position, in which it is out of engagement with the recording medium (10).
14. Inverter according to one of Claims 1 to 13, designed as an independent structural unit and fastened in an electrographic printer such that it can be pulled out by means of a displacing device (55).
15. Electrographic printing device for printing onto recording media (10) in web form, having

    - an inverter according to one of Claims 1 to 14;

    - an intermediate medium (11) with associated units (12, 13, 14, 16) for producing toner images on the intermediate medium (11),

    - a transfer-printing station (15), assigned to the intermediate medium (11) and receiving the recording medium (10);

    - a fixing station (18), arranged downstream of the transfer-printing station (15) in the transporting direction of the recording medium, for fixing the toner images on the recording medium, intermediate medium (11), transfer-printing station (15) and fixing station (18) having a usable width of at least twice the web width of the recording medium (10), and the inverter (28) being arranged downstream of the fixing station (18) and adapted such that it can be coupled to the transfer-printing station (15) via the paper run-out channel (31).
16. Electrographic printing device according to Claim 15, the paper run-in channel (30) of the inverter being in coupleable connection, via paper transporting elements (57), with a recording-medium delivery channel (29) which is assigned to the fixing station (18) and has a useable width of at least twice the web width of the recording medium (10).

Images