EP0436756A1 - Precision docking device for an ink jet print head cleaning and capping station in an ink jet printer - Google Patents

Abstract

For the precision docking of a cleaning and capping station (6, 6b) on an ink jet print head (8) which can be moved by line in an ink jet printer (1), the cleaning and capping station (6, 6b) is coupled to a pivoting device (31) for pivoting the cleaning and capping station (6, 6b) onto the ink jet print head (8). The cleaning and capping station (6, 6b) is mounted so as to be laterally displaceable relative to a docking position of the ink jet print head (8) in a given catch region (a), adjusting elements (33, 81) being assigned both to the cleaning and capping station (6, 6b) and to the ink jet print head (8), which adjusting elements engage in one another when the cleaning and capping station (6, 6b) is pivoted onto the ink jet print head (8) situated in the vicinity of a docking position and thus centre the cleaning and capping station (6, 6b) on the ink jet print head (8). <IMAGE>

Description

The invention relates to a device for accurately docking a cleaning and sealing station to an ink print head that can be moved line by line in an ink print device.

Ink printing devices with cleaning and sealing stations are generally known. For example, DE-Al-33 16 474, DE-Al-33 16 968, DE-Al-36 04 373, DE-Al-36 11 333, DE-Al-36 33 239, DE-Al-37 26 671, DE-Al-38 10 698 and EP-Al-0 094 220 each describe cleaning and sealing stations or suction regeneration devices for ink print heads in ink print devices, with which the outlet openings of the ink print heads are cleaned, rinsed and in longer ways in different ways Pauses in writing the ink printing device can be sealed. For this purpose, the cleaning and sealing stations or the suction regeneration devices are preferably arranged in a parking position outside the work area of a printer carriage carrying the ink print heads in the ink print device.

In cleaning and sealing stations, which are arranged stationary in the printer, considerable tolerances occur between the ink print head and the suction or cover cap of the cleaning and sealing station, which are very difficult to accurately and tightly dock the ink print head to the cleaning and sealing station.

A precise and exact docking of the ink print head to the cleaning and sealing station is particularly necessary, however, if an ink print head with several rows of nozzles is used, for example each row of nozzles with a separate one colored writing fluid is operated. Each row of nozzles must be assigned its own suction chamber for the cleaning and sealing station in order to prevent color mixing. To create a high-quality typeface, the rows of nozzles must also be arranged as close as possible to one another.

In order to enable the individual rows of nozzles to be sealed and vacuumed or rinsed exactly, the corresponding sealing elements of a suction or cover cap of the cleaning and sealing station must always be positioned exactly between the rows of nozzles. Inaccurate positioning of the sealing element can lead to the mixing of ink liquids of different colors in the area of the nozzle outlet openings. Furthermore, inaccurate positioning hinders the suction and cleaning function of the cleaning and sealing station.

The object of the invention is therefore to provide a device for ink-printing devices for the precise docking of a cleaning and sealing station to an ink-print head.

Another object of the invention is to design the device such that an exact docking of the cleaning and sealing station on the ink print head is possible even when the starting position of the ink print head is subject to high tolerances.

This object is solved by the features of claim 1.

Advantageous embodiments of the invention are characterized in the subclaims.

Characterized in that the cleaning and sealing station with respect to a docking position of the ink print head is laterally displaceably mounted in a tolerance-related capture area and both the cleaning and sealing station and the ink print head adjusting element has that interlock when docking and center the cleaning and sealing station on the ink print head, a particularly precise docking of the ink print head at the cleaning and sealing station is possible regardless of tolerances.

If you place a fixed positioning device in the catch area of the cleaning and sealing station, which positions the cleaning and sealing station in a predeterminable starting position when the cleaning and sealing station is in an idle state, the ink printhead will dock onto the cleaning and sealing station precisely, even with large tolerances possible to be taken by the ink printhead. It is sufficient if the ink print head is moved into the vicinity of the docking position. The actual docking position of the ink printhead can fluctuate within a large tolerance range around the starting position of the cleaning and sealing station.

For exact positioning of the cleaning and sealing station on the ink print head, a pivotable centering finger with centering bevels is arranged on the cleaning and sealing station, which dips into a corresponding centering opening on the ink print head.

In an advantageous embodiment of the invention, the pivotable centering finger has insertion bevels tapering to an acute angle on two opposite sides. To dock the cleaning and sealing station, it dips one side into a corresponding centering window of the ink print head and thus centers the cleaning and sealing station. If the docking connection is released, the centering finger swings back and dips with its other side into a corresponding, stationary centering window of the printing device. This means that the cleaning and sealing station is positioned in a defined starting position after each docking process.

• Figur 1 eine Draufsicht auf eine Tintendruckeinrichtung,
• Figur 2 eine perspektivische Darstellung einer Reinigungs- und Dichtstation,
• Figur 3 bis 11 verschiedene, von der Drehrichtung abhängige Zustandsdiagramme einer Weichenkupplung,
• Figur 12 bis 14 in verschiedenen Ansichten eine in einem Schwenkhebel der Reinigungs- und Dichtstation angeordneten Saug- und Abdeckkappe,
• Figur 15 einen Aufbau der Saug- und Abdeckkappe,
• Figur 16 einen Schnitt durch die Saug- und Abdeckkappe nach
• Figur 15 entlang einer Schnittlinie XVI ... XVI,
• Figur 17 in einer Rückansicht einen Aufbau eines Trägerteils der Saug- und Abdeckkappe,
• Figur 18 in einer Vorderansicht eine zweite Ausführungsform einer Saug- und Abdeckkappe,
• Figur 19 einen Schnitt durch die Saug- und Abdeckkappe nach Figur 18 entlang einer Schnittlinie XIX . .. XIX,
• Figur 20 bis Figur 29 verschiedene Zustände eines Zentrierfingers der Reinigungs- und Dichtstation nach Figur 2 beim An- und Abkoppeln einer Saug- und Abdeckkappe an bzw. von einem Tintendruckwerk,
• Figur 30 eine Vorderansicht einer zweiten Ausführungsform einer Reinigungs- und Dichtstation,
• Figur 31 eine Draufsicht der Reinigungs- und Dichtstation nach Figur 30,
• Figur 32 eine Seitenansicht der Reinigungs- und Dichtstation nach Figur 30.

Exemplary embodiments of the invention are explained with reference to the drawings in FIGS. 1 to 32. Show it:

• FIG. 1 shows a plan view of an ink printing device,
• FIG. 2 shows a perspective illustration of a cleaning and sealing station,
• 3 to 11 different state diagrams of a switch coupling, which are dependent on the direction of rotation,
• FIGS. 12 to 14, in different views, a suction and cover cap arranged in a pivoting lever of the cleaning and sealing station,
• FIG. 15 shows a structure of the suction and cover cap,
• Figure 16 shows a section through the suction and cover cap
• FIG. 15 along a section line XVI ... XVI,
• FIG. 17 is a rear view of a structure of a carrier part of the suction and cover cap,
• FIG. 18 is a front view of a second embodiment of a suction and cover cap,
• 19 shows a section through the suction and cover cap according to FIG. 18 along a section line XIX. .. XIX,
• 20 to 29 different states of a centering finger of the cleaning and sealing station according to FIG. 2 when coupling and uncoupling a suction and cover cap to or from an ink printing unit,
• FIG. 30 shows a front view of a second embodiment of a cleaning and sealing station,
• FIG. 31 shows a top view of the cleaning and sealing station according to FIG. 30,
• FIG. 32 shows a side view of the cleaning and sealing station according to FIG. 30.

Figure 1 shows a top view of a basic structure of an ink printing device 1. Characteristic for the structure of the ink printing device 1 is an ink printing unit 8 arranged on a printer carriage 7, which is arranged parallel to a platen in the form of a platen roller, which is rotatably mounted in two housing walls 100, 102 of a supporting structure 10 9 can be moved. The platen roller 9, which is driven by a drive device 90 with a first drive pinion 900 via a gear 91 in the direction of rotation shown, transports a sheet-shaped recording medium, which extends, for example, over a printing area DB, into a printing zone formed by the ink printing unit 8 and the platen roller 9 DZ. In order to be able to print on the recording medium, in the present case, if the ink printing device 1 is designed as a four-color printer, the ink printing unit 8 has four ink print heads 80 arranged next to one another with nozzle outlet surfaces 800 facing the recording medium. The four available colored writing fluids are the colors yellow, magenta, cyan and black. The colored writing liquids can be assigned to the four different ink print heads 80 as desired. However, for reasons relating to the cleaning of the ink print heads 80, it is advisable to assign the colors to the ink print heads 80 from right to left in the order mentioned.

The print zone DZ is the area of the sheet-shaped recording medium opposite the ink print heads 80. In order to be able to print on the sheet-shaped recording medium over the entire width of the printing area DB, the printer carriage 7 is moved back and forth on two parallel guide rods 70 fastened in the housing walls 100, 102. The back and forth movement of the printer carriage 7 takes place, as described in DE-GM 89 06 727, by a flexible traction means 71 which loops around a deflection roller 72 and a second drive pinion 730 of an electric motor 73.

To print on the recording medium guided over the platen roller 9 in the printing area DB, the printer carriage 7 is moved back and forth with the ink printing unit 8 between the positions delimiting the printing area DB. Both mono-directional printing and bidirectional printing are possible as the operating mode. In mono-directional printing, the record carrier is only written line by line in one direction of movement, in bidirectional print operation - which allows a significantly higher printing speed - the record carrier in the print area DB is printed line by line in both directions of movement of the ink printing unit 8 (ink print head).

Regardless of the operating mode, at the start of printing the printer carriage 7, which is in a rest position C outside the printing area DB, is first accelerated to position A so that it reaches the relative speed to the recording medium required for continuous printing. Position A defines the first possible printing position. Thereafter, the printing carriage 7 is moved in the actual printing area DB for printing at a constant speed until it has reached the position B, which determines the last possible printing position of the printing area DB. After the position B has been exceeded, the printer carriage 7 is braked to the position D and brought to a standstill, and then the recording medium is moved one more line over the platen roller 7. To print the following line, the printer carriage is accelerated in the opposite direction from position D to position B, which now defines the first printing position of the following line to be printed. After the printing speed in position B has been reached, the next line between positions B and A can be printed. When the printer carriage 7 reaches the last possible printing position A, it is braked again to position C. Now there is a new line feed with new line printing. Line by line of the recording medium is now printed in the manner described.

In mono-directional operation, it is convenient to move the printer carriage from position B to position C in rapid return.

The distances CA and BD are hereinafter referred to as overshoot areas UEB. Their minimum length is determined by the physically required acceleration and braking distances, taking mechanical tolerances into account. In the exemplary embodiment described in connection with FIG. 1, the overshoot area UEB is approximately 40 mm long.

In the printing operation, dirt can occur on the ink print heads 80 due to paper dust, which is why the ink print heads 80 must be cleaned from time to time. The ink print heads 80 are rinsed in that ink is sucked out of the ink print heads 80 via the nozzle outlet openings. Flushing the ink printheads 80 also prevents ink from drying out at nozzle exit openings of ink printheads 80 that have not been used in the writing operation. For this purpose, a cleaning and sealing station 6 is provided in the ink printing device 1. The cleaning and sealing station 6 is arranged in an overshoot area UEB of the printer carriage 7. This can be a left-hand as well as a right-hand overshoot area UEB. The overshoot range on the left has proven to be advantageous.

For cleaning the ink print heads 80, the printer carriage 7 is moved into the overshoot area UEB until it abuts the housing wall 100 of the supporting structure 10. The housing wall 100 forms a common reference edge for the cleaning and sealing station 6 and the printer carriage 7, which is important for the cleaning process. How the cleaning process proceeds in detail is explained on the basis of the description of FIGS. 2 to 32.

Figure 2 shows a perspective view of the structure of the cleaning and sealing station 6, hereinafter referred to as RD station. The RD station 6 is designed as an autonomous unit that functions independently of the ink printing device 1. It can be used as a closed structural unit in the ink printing device. This has the advantage that the RD station 6 can be used as an OEM product (original equipment manufacturing) in various ink printing devices. With it, service treatments of the ink print heads 80 are carried out, which are necessary for trouble-free operation of the ink print device 1. These include a .: The cleaning of the ink printhead 80 with its nozzle outlet openings at predetermined time intervals, in order to thereby prevent the nozzle outlet openings from drying out and becoming dirty; the suction of ink contained in the ink print head 80 in the event of faults, e.g. to remove any air that has entered and - in the idle state of the ink printing device 1 - to cover the nozzle outlet openings in order to prevent them from drying out and becoming dirty, e.g. to protect by dusting through paper dust. In addition, when transporting and storing the ink printing device 1, it must be avoided that ink leaks from the nozzle outlet openings.

Since the RD station 6 according to FIG. 1 is arranged within the overshoot range UEB resulting from the writing operation of the ink printing device 1 for the printer carriage 7 carrying the ink printing unit 8, the ink printing device 1 has a narrower structure.

In writing operation, if the printer carriage 7 is temporarily in the overshoot area UEB due to acceleration and braking processes, the RD station 6 must not block the overshoot distance of the printer carriage 7 between position A and position C according to FIG. 1.

In service mode, if the nozzle outlet openings of the ink printing unit 8 are to be cleaned, the RD station 6 must be in the correct position docked to the ink printing unit 8 and the ink is sucked out of the nozzle outlet openings. “Docking” is understood to mean coupling the RD station 6 to the ink printing unit 8.

In the idle state, during transport and during storage of the ink printing device 1, the nozzle outlet openings must be protected from drying out. Furthermore, no ink should leak. For this reason, it is necessary to dock the RD station 6 precisely on the ink printing unit 8 and thus to close the nozzle outlet openings.

The RD station 6 contains a switch coupling 2, a swivel lever 3, a suction and cover cap 4, hereinafter referred to as an SA cap, and a bellows pump 5. The switch coupling 2 has a cam disk 20 and an impeller 21, which is on the cam disk 20 rolls. The cam disk 20 is positively attached to a torque DM on a drive shaft of a further electric motor, not shown in FIG. 2. A DC motor is preferably used as the electric motor.

Furthermore, the cam disk 20 has, on the end face side facing away from the electric motor, an eccentrically arranged, projecting crank pin 200, which is connected via a linkage 50 to a bellows 51 of the bellows pump 5. Due to the rotation of the cam disc 20 with the eccentrically arranged crank pin 200, the bellows 51 is alternately pulled apart or compressed via the linkage 50. The resulting pumping action of the bellows pump 5 is used in the present RD station 6, for example to pump the ink out of the nozzle outlet openings of the ink print heads 80 in FIG. 1. For this purpose, the bellows pump 5 is connected to the SA cap 4 both via a hose 52 and via an air hose 53. With the RD station 6, however, it is also possible to draw off and dispose of other liquids from various spray devices.

For pumping the ink out of the ink print heads 80 of the ink print device 1, four identically shaped, identically shaped recesses (suction openings, cavities) 40 are arranged in the SA cap 4. These are connected on the one hand via the hose 52 (suction channel) to a disposal container 54 attached to the bellows pump 5, and on the other hand via the air hose 53 (pressure compensation channel) to the ambient air. The air hose has e.g. controllable ventilation valve 55 coupled to the bellows pump 5. For this purpose, the air hose 53 is placed over a ventilation nozzle 43 which protrudes laterally from the SA cap 4. As an alternative to the bellows pump 5, the ink can also be sucked out of the nozzle outlet openings with a hose, piston and membrane pump.

The number of recesses 40 contained in the SA cap 4 of the RD station 6 depends on the number of ink printheads used. If, as in the present case, for example, a four-color print image is to be produced with the ink print device 1, the service treatment of the ink print device 1 must also be designed for the disposal of the required four ink print heads. In order to avoid mixing of the writing liquids during the suction from the nozzle outlet openings of the ink print heads, the number of recesses 40 or suction openings is identical to the number of colored writing liquids assigned to the ink print heads.

A trough-shaped rubber insert 41 in the form of an elastic cap is arranged in the suction openings 40 on the side of the SA cap 4 facing the ink printing unit 8. This has a liquid-absorbing insert 42. For pumping the ink out of the ink print heads 80, the SA cap 4, as already mentioned, is docked onto the ink printing unit 8, the elastic caps 41 being placed over the nozzle outlet openings. If in the following the docking of the SA cap 4 is mentioned, it is a lateral shift and pivoting the SA cap 4 meant. So that the ink can be pumped out properly via the suction openings 40 and the hose 52, a sealing lip 410 is arranged on the trough-shaped rubber insert 41, which surrounds a trough opening 411 of the rubber insert 41 and is pressed against the ink printing unit 8 when the SA cap 4 is docked and thereby hermetically seals the nozzle outlet openings of the ink print heads 80.

The SA cap 4 is docked by the pivot lever 3, which is mounted on a first axis 30 clamped between the housing wall 100 and a further housing wall 101 of the supporting structure 10 so that it can be moved and pivoted. In order to be able to move and pivot the pivot lever 3 with minimal effort, the effects of friction must be kept as small as possible.

The pivoting process is triggered in that the torque DM emitted by the electric motor is converted via the switch coupling 20 into a tilting moment KM acting on the pivoting lever 3. For the conversion of the torque DM, the swivel lever 3 is sprung onto the cam disk 20 via the impeller 21. In order to keep the forces occurring during the springing small, the swivel lever 3 is constructed in two parts and thus the own weight of the swivel lever 3, which is also responsible for the frictional influences, is divided. The two-part structure of the pivot lever 3 is, however, essentially explained by the fact that a lateral displacement of the pivot lever 3 may be required for a precise docking of the SA cap 4. In the case of a one-piece construction, this would lead to displacement of the impeller 21 on the cam disk 20. The running surface for the impeller 21 on the cam disk 20 would have to be designed for a maximum lateral displacement during docking in a one-piece construction.

An upper lever part 31 of the swivel lever 3 carrying the SA cap 4 can be swiveled and displaced via two swivel arms 310, 311 arranged on the axis 30. The upper lever part 31 of the pivot lever 3 also has two opposing support arms 312, 313 which are connected to one another on the side facing away from the ink printing unit 8 via a U-shaped cross strut 314. In a first embodiment, a T-shaped recess 315 is embedded in the legs of the U-shaped cross strut 314 for the mounting of the SA cap 4. This serves for the freely movable mounting of trunnions 44 of the SA cap 4. For the mounting of the SA cap 4, the trunnions 44 are pressed into the T-shaped recess 315. Between the swivel arms 310, 311 and the support arms 312, 313, the lever upper part 31 also has a rectangular central part 316, into which a pocket-shaped formation 317 is embedded.

A positioning device is provided so that the SA cap 4 can also be docked to the ink printing unit 8 in the correct position. This consists of two opposing centering fingers 33 tapering at an acute angle in the pivoting direction of the pivoting lever 3, which are arranged on the side of the support arm 313 on the leg of the U-shaped cross strut 314. For this purpose, a first centering finger 33 independently searches for a first centering window 81 (FIG. 12), which is embedded in the ink printing unit 8 and is not shown in FIG. 2, and thus positions the RD station 6 in relation to the ink printing unit 8 for positioning purposes the swivel lever 3 can be moved laterally with the RD station 6.

For the docking of the SA cap 4, the tilting moment KM is transmitted to the upper lever part 31 of the pivot lever 3 via a lower lever part 32 of the pivot lever 3. For this purpose, the lower lever part 32, like the upper lever part 31, is pivotably arranged on the axis 30. Characteristic of the lower lever part 32 are a lever arm 320 and a secondary arm 321 through which the axis 30 is inserted in the middle or at the base point. Between the lever arm 320 and the secondary arm 321, a first recess 322 is provided in the region of the axis 30, in which the swivel arm 310 of the lever upper part 31 is arranged. The dimensions of the recess 322 are chosen so that the upper lever part 31 can be moved laterally independently of the lower lever part 32 as required. In addition, a second recess 323 is provided between the lever arm 320 and the secondary arm 321, in which the impeller 21 is axially movable and rotatably mounted on a second axis 35. A first spring 36 is also arranged on the axis 35 within the recess 323 and counteracts the axial mobility of the impeller 21 with a first spring force F1. The axis 35 also passes through a third recess 324, which is embedded at the base of the lever arm 320. Within this third recess 324, a second spring 37 is suspended on the axis 35 with a spring force F2, which is also connected to the support structure 10 of the ink printing device 1 for the pivoting operation of the pivoting lever 3, but not shown in FIG. 1. The second spring force F2 of the spring 37 pushes the impeller 21 against the cam disk 20. The pivoting movement of the pivoting lever 3 required for docking the SA cap 4 is transmitted from the lever arm 320 of the lower lever part 32 to the upper lever part 3l. For this purpose, the lever arm 320 engages with a small play in the swivel direction of the swivel lever 3 in the manner of a sliding block into the pocket-shaped configuration 317 of the lever upper part 31 between the swivel arms 310, 311. In order to be able to move the upper lever part 31 on the axis 30, the pocket-shaped configuration 317 of the upper lever part 31 is wider than the lever arm 320 of the lower lever part 32 by the amount which is required as a lateral displacement of the upper lever part 31 and thus the SA cap 4.

Figures 3 to 7 and Figures 10 and 11 show a side view of the structure and operation of the switch coupling 2 based on the angle-dependent states of the switch coupling 2 for different directions of rotation of the cam disc 20. The two directions of rotation of the cam disc 20 are used to help in the description of the Figure 2 to implement the operating modes of the RD station 6. When turning the right 3, 5 and 10, the SA cap 4 integrated in the swivel lever 3 is constantly alternately docked onto the ink printing unit 8 (FIG. 3) and lifted off the ink printing unit 8 again (FIG. 10). 4, 6, 7 and 11, the swivel lever 3 is docked to the ink printing unit (FIG. 4) and the ink is sucked out of the nozzle outlet openings of the ink printing head by the bellows pump 5 (FIGS. 6, 7, 11) until the direction of rotation is changed again.

For the swiveling or suction process, the cam disk 20 has two radially running cam tracks 201, 202 which are offset from one another by a step shoulder x, in which an outer, motion-triggering cam track 202 according to FIGS. 3, 4 and 10 serves as a tread for the cam disk 20 rolling impeller 21 is used. In order to be able to carry out a stroke required for docking the SA cap 4 to the ink printing unit 8 and a stroke required for lifting the SA cap 4 off the ink printing unit 8, the full step offset x between the cam tracks 201, 202 is for example for two thirds of the Effective circumference on the cam disc 20. Characterized in that the movement-triggering, outer cam track 202 nestles at these points against an inner cam track 201 designed as an idle track, the position of the impeller 21 under the spring force F2 or against the spring force F2 is shifted by the amount of the stroke relative to the cam disk 20 .

FIGS. 3 and 4 each show a possible initial state of the switch coupling 2, in which the impeller 21 rests on the outer cam track 202 of the cam disk 20 and thus the SA cap 4 according to FIG. 2 integrated in the pivot lever 3 in the lifted state from the ink printing unit 8 located. An equilibrium force FG compensating the spring force F2 is absorbed by the rotatably mounted cam disk 20. The impeller 21, the pivot lever 3 and the SA cap 4 form a double-armed mechanical lever arrangement, in which the spring force F2 acting on the lever arrangement either via the impeller 20 or the SA cap 4 is compensated. If the cam disk 20 is now rotated in the direction of the arrow shown in FIG. 3 to the right or in FIG. 4 to the left, the impeller 21 leaves the outer cam track 202 of the cam disk 20 under the spring force F2 in both cases according to Figure 2, the docking of the SA cap 4 to the ink printing unit 8 by the pivot lever 3 is pivoted about the stroke.

Depending on the condition of the ink printing device 1, z. B. write or service operation and idle state, for the given direction of rotation of the cam disc 20 must now either, for example, the left rotation of the cam disc 20, pumping or lifting of the SA cap 4 is initiated. A switch tongue 203 operating according to the coupling principle is provided for this. This is arranged in the area of the cam disk 20 outside the step shoulder x. It sweeps the inner cam track 201 at an angle, is firmly connected to the cam disk 20 at one end and resiliently rests against a flange 204 of the cam disk 20 at the other end. The switch tongue 203 is dimensioned and arranged on the cam disk 20 so that the impeller 21 does not move any further when the cam disk 20 is turned to the left, i.e. the impeller 21 idles relative to the moving cam disk 20, and two turns per revolution when the cam disk 20 is turned to the right Can perform position shifts.

The correct selection of the direction of rotation as a function of the operating mode of the ink printing device 1 is carried out by a control device which, like the RD station 6, is part of the ink printing device 1. For this purpose, the control device is coupled to the electric motor. For the control of the electric motor, the control device contains, for example, a microprocessor which, via a generally known electronic circuit arrangement, changes the polarity of a supply voltage applied to the electric motor and thereby changes the direction of rotation of the electric motor. In addition to controlling the electric motor In the RD station 6, the electric motor 73 and the drive device 90 according to FIG. 1 are also controlled by the control device. The control device is generally constructed in the usual way.

5, 6 and 7 each show a state of the switch coupling 2, in which the impeller 21 has left the outer cam track 202 and the SA cap 4 is thus docked to the ink printing unit 8. It is characteristic of this state in FIGS. 5, 6 and 7 that the impeller 21 in the docked state of the SA cap 4 does not rest on the outer cam track 202 or on the inner cam track 201 of the cam disk 20. When the impeller 21 leaves the outer cam track 202, the mechanical lever arrangement, under the influence of the spring force F2, endeavors to return to a state of support. This is achieved in that, in contrast to FIGS. 3 and 4, where the equilibrium force FG compensating the spring force F2 was applied by the rotatably mounted cam disk 20, the equilibrium force FG compensating the spring force F2 is now applied by the ink printing unit 8. This means that the stroke to be carried out by the pivot lever 3 for docking the SA cap 4 to the ink printing unit 8 is smaller than the step offset x between the cam tracks 201, 202 of the cam disk 20. This results in an air gap Δ x around which the impeller 21 is lifted off the inner cam track 201 of the cam disk 20. The air gap Δ x ensures that no additional frictional influence occurs when changing the path of the impeller 21 according to FIGS. 6 and 7. As a result, the spring force F1 which presses the impeller 21 against the rim 204 of the cam disk 20 can be small. A typical stroke value for the RD station 6 is, for example, between 6 and 10 mm. While the impeller 21 according to FIG. 5 is moved relative to the cam disk 20 between the rim 204 and the switch tongue 203, the impeller 21 according to FIGS. 6 and 7 is guided past the switch tongue 203 relative to the cam disk 20.

Figures 8 and 9 each show a top view of the state of the Switch coupling 2 according to FIG. 5 or FIG. 7. It is made clear that the impeller 21 pressed on the axis 35 by the spring 36 with the spring force F1 against the rim 204 of the cam disk 20 during the clockwise rotation of the cam disk 20 in FIG. 8 between the switch tongue 203 and the rim 204 are moved relative to the cam disk 20 and, when the cam disk 20 is turned to the left in FIG. 9, it is guided past the switch tongue 203 relative to the cam disk 20.

During the relative movement of the impeller 21 according to FIG. 8, the end of the switch tongue 203 which resiliently braces against the rim 204 is pressed away from the impeller 21.

During the relative movement of the impeller 21 according to FIG. 9, the impeller 21 is displaced on the axis 35 and the spring 36 is compressed in the process. The spring 36 is compressed by the impeller 21 until the impeller 21 has passed the switch tongue 203.

FIG. 10 shows how the impeller 21 reaches the outer cam track 202 again against the spring force F2 when the cam disk 20 is turned further to the right, and thus the SA cap 4 is lifted off the ink printing unit 8. If the cam disk 20 is turned further to the right, the state of the switch coupling 2 shown in FIG. 3 is reached again and the docking or lifting of the SA cap 4 begins again.

FIG. 11 shows how the impeller 21 is pressed by the spring force F1 against the step shoulder x of the offset cam tracks 201, 202 when the cam disk 20 is turned further to the left after passing the switch tongue 203 in FIGS. 7 and 9. When the cam disk 20 is turned further to the left, the state of the switch coupling 2 shown in FIG. 6 is reached again and the ink is pumped out of the nozzle outlet openings of the ink print heads 80.

FIG. 12 shows a top view of the pivotable mounting of the to the ink printing unit 8 securely docked SA cap 4 in the pivot lever 3. For the exact docking of the SA cap 4, the first centering finger 33 is immersed in the centering window 81 of the ink printing unit 8 and thus aligns both the pivot lever 3 and the SA cap 4 opposite the inkjet 8 laterally. The independent alignment of the SA cap 4, which is independent of the pivoting process of the pivot lever 3, is made possible in that on the one hand the SA cap 4 is pivotally and freely movable in the lever upper part 31 and on the other hand a pressing force FA necessary for docking is achieved via the u- shaped cross brace 314 is transferred centrally and evenly. For this purpose, the u-shaped cross strut 314 has a spherical cap 318 which is aligned with the center of gravity of the SA cap 4 and via which the pressing force FA is transmitted to the SA cap 4. A pressure plate 60 arranged on the back of the SA cap 4 bears against the spherical cap 318. The SA cap 4, which is freely movable and pivoted at right angles to the ink printing unit 8, is also aligned at right angles to the ink printing unit 8. The pressure force FA corresponds to the amount of the spring force F2 and acts on the pivot lever 3 in the opposite direction to the spring force F2.

FIG. 13 shows a side view of how the SA cap 4 is mounted in the upper lever part 31 of the pivot lever 3. In a second embodiment for the mounting of the SA cap 4, an elongated hole 319 is arranged in the legs of the U-shaped cross strut 314, into which the bearing pins 44 of the SA cap 4 are freely movable in the direction of the pressing force FA. The elongated hole 319 is appropriate because the position of the SA cap 4 relative to the ink printing unit 8 orthogonal to the direction of the pressing force FA is not critical for the docking of the SA cap 4 with the ink printing unit 8.

In contrast to the first embodiment for the storage of the SA cap 4, in which the SA cap 4 is pressed into the T-shaped recess 315, the support arms 312, 313 for the second embodiment must be able to be pressed apart in order to to store the SA cap 4 in the pivot lever 3. In addition to the SA cap 4, the switch coupling 2 except for the switch tongue 203, the pivot lever 3 is consequently preferably also made of plastic. In the first embodiment for the storage of the SA cap 4, however, it would also be possible to make all of the elements of the RD station 6 mentioned metallic.

FIG. 13 also shows, on the underside of the SA cap 4, a suction connection 45 for the hose 52, via which the ink sucked out of the nozzle outlet openings is transported into the disposal container 54.

In FIG. 14, a rear view of the SA cap 4, which is pivotably and freely movably mounted in the pivot lever 3, shows how the spherical cap 318 is arranged on the inner surface of the U-shaped cross strut 314 and the suction connection 54 to the underside of the SA cap 4 is.

FIG. 15 shows a top view of the detailed structure of a first embodiment of the SA cap 4 with the four suction openings (cavities) 40 for the separate suction of the ink from the nozzle outlet openings of the ink print heads 80. Both the shape of the suction openings (cavities) 40 and To show the structure of the rubber insert 41 in FIG. 15, the rubber insert 41 is inserted in two of the suction openings 40 and one of the rubber inserts 41 is also cut open in the longitudinal direction.

The SA cap 4 has a rectangular support part 46, for example rounded in the corners, into which the recess 40 of the suction openings are let in in an evenly distributed manner both in length and in width. Each of the suction recesses 40 contains a pressure equalization channel (403, 463) for the pressure equalization and a suction channel (461, 401) for discharging the sucked-off ink as well as a centrally arranged opening 462 for fastening the trough-shaped rubber insert 4l, 41a. For receiving the trough-shaped rubber insert 41, 41a The recess 40 has a preferably oval first chamber 400. The trough-shaped rubber insert 41 can be inserted into this oval chamber 400 and fastened to the opening 462. The pressure compensation channel consists of a connection opening 463 with associated chamber 402, the suction channel consists of a connection opening 461 with associated second chamber 401.

Instead of oval, the first chamber 400 can also be rectangular with slightly rounded corners. Here, however, it must be ensured that the rubber insert 41 can continue to be arranged in a form-fitting manner in the first chamber 400.

The rubber insert 41 with the sealing lip 410 surrounding the tub opening 411 and the insert 42 arranged in the rubber insert 41 has the task of sealing the nozzle outlet openings of the ink print heads 80 when the SA cap 4 is docked on the ink printing unit 8, so that when the ink is sucked away they do not can escape at the docking point between the sealing lip 410 and the nozzle exit surface 800 of the ink printing unit 8. Since the ink is sucked out of the nozzle outlet openings of the ink print heads 80 with the aid of a negative pressure, the rubber insert 41 must have a certain elasticity on the one hand for sucking off the ink and on the other hand a certain rigidity for docking the SA cap 4. A suitable compromise between the elasticity and the rigidity of the rubber insert 41 is achieved in that the trough-shaped rubber insert 41 according to FIG. 15 has a trough base 412 forming the trough shape with a web 414 enclosing the trough base 412 and designed as a hollow profile with Guerribs 413. The transverse ribs 413 are arranged in the web 414 designed as a hollow profile in such a way that a lamella-like structure is produced. On the other hand, the transverse ribs 413 protrude as small elevations onto the trough bottom 412 into the trough-shaped rubber insert 41. This ensures that the insert 42 does not rest directly on the trough bottom 412 of the rubber insert 41. In the tub floor 412 are still on its longitudinal axis two passage openings 415, 416 spaced apart from one another by a distance y. The distance y preferably corresponds to 2/3 of the total length of the longitudinal axis of the trough base 412. A first passage opening 415 of the rubber insert 41 let into the cavity 40 opens into the pressure compensation channel 403, which is connected to the ventilation nozzle 43. A second passage opening 416 of the rubber insert 41 opens into the suction channel 401, which is connected to the suction nozzle 45.

FIG. 16 shows a cross section through the SA cap 4 according to FIG. 15 along a section line XVI ... XVI. The carrier part 46 of the SA cap 4 is covered on the back with a cover plate 47, by which the chambers 401, 402, 403 are closed. Along the section line XVI ... XVI, the cover plate 47 has a recess 470 which is covered with an oval sieve 48. The sieve 48 is arranged in a form-fitting manner in a recess 464 of the carrier part 46, and is pressed against the carrier part 46 by a projection 471 of the cover plate 47 during assembly of the SA cap 4. When mounting the SA cap 4, the cover plate 47 is welded to the carrier part 46, for example. However, it is also possible to releasably connect the cover plate 47 to the carrier part 46. It only has to be ensured that no ink can escape from the SA cap 4. The recess 470 forms with the chambers 401 of the suction channels of the recesses 40 and the sieve 48 a common removal channel which has the suction nozzle 45 as an outlet. When inserting the rubber insert 41 into the cavity 40, the sieve 48 serves as a stop for a funnel-shaped nozzle 417, which is arranged on a knob-shaped extension 418 of the trough base 412 in the region of the second passage opening 416. Through the knob-shaped extension 418 and the funnel-shaped nozzle 417, the passage opening 416 is extended to the sieve 48.

The knob-shaped extension 418 has a brim-like design for inserting the rubber insert 41 into the cavity 40 Projection 419, which engages behind the partition 460 when the knob-shaped extension 418 is pushed through a first bore 461. The total length of the knob-shaped extension 418 and the funnel-shaped connecting piece 417 is designed such that the ink liquid drawn through the passage opening 416 passes from the nozzle outlet openings only in the area of the funnel-shaped connecting piece 417 via the sieve 48 into the recess 470.

In the area of the first passage opening 415 and in the middle of the trough base 412, two further knob-shaped extensions 418 with the brim-like projection 419 are arranged below the trough base 412, which also when the knob-shaped extension 418 is pushed through a second bore 462 or a third bore 463 engages behind the partition 460. The knob-shaped extension 418 is formed in the area of the first passage opening 415 in such a way that the passage opening 415 opens into the fourth chamber 403. The rubber insert 41 is evenly fastened in the carrier part 46 by the knob-shaped extension 418 in the middle of the trough base 412. This has the advantage that the rubber insert 41 docked to the ink printing unit 8 is not lifted out of the first chamber 400 when the ink is sucked off in the region between the two through openings 415, 416.

The differently colored writing liquids that have thus entered the recess 470 from the SA cap 4 via the rubber inserts 41 arranged in the cavities 40 are passed through the sieve 48 and a collecting basin 49 arranged in the carrier part 46 through a drain 450 of the suction nozzle 45 opening into the collecting basin 49 sucked into the disposal container 54. The collecting basin 49 is preferably arranged in the middle of the carrier part 46 between two adjacent chambers 401 of the suction channels of the recesses 40. The funnel-shaped connecting pieces 417 which rest against the sieve (filter) 48 prevent ink or ink mixture from penetrating into adjacent suction channels or their recesses 40 when the ink is sucked off via the suction channels and the recess 470.

FIG. 17 shows a rear view of the support part 46 that has not been welded to the cover plate 47. The catch basin 49 is then, like the chambers 401, the oval recess 464 for the sieve 48 a component of the channel system connected to the suction connection 45. In order to be able to distribute the air evenly from the ventilation valve 55 via the air hose 53 and an air cannula 430 of the ventilation nozzle 43 to the pressure equalization channels 403 of the SA cap 4, these are also made into a pressure equalizing trough 465 recessed into the carrier part 46. Channel system interconnected. As with the duct system for the suction nozzle 45, the duct system of the ventilation nozzle 43 is also closed by welding the cover plate 47 to the carrier part 46.

After the description of the detailed structure of the SA cap 4, the function of the SA cap 4 is as follows:

To clean the nozzle outlet openings of the ink print heads 80, for example filling and rinsing the ink print heads 80, the SA cap 4 is pressed against the ink printing unit 8 with the ventilation valve open. Docking the SA cap 4 with the ventilation valve open is necessary because when the SA cap 4 was put on, the air was pressed into the nozzle outlet openings by the contact pressure which was created. This would destroy the ink menisci in the nozzle orifices. Air flowing into the nozzle outlet openings leads to failure of the ink pressure device 1. The control of the ventilation valve 55 is again carried out by the control device in the ink pressure device 1.

After the SA cap 4 is docked on the ink printing unit 8, the ventilation valve is closed and the pumping process is initiated by reversing the direction of rotation of the cam disk 20. Here, the ink is sucked out of the nozzle outlet openings of the ink print heads 80 with the aid of a negative pressure which results from the closing of the ventilation valve. The ink emerging from the nozzle outlet openings is first of all from the Insert 42 added. If the liquid-absorbing insert 42 is saturated with the ink, the remaining ink passes through the second passage opening 416 of the rubber insert 41, the suction channel 401 and the sieve 48 into the collecting basin 49 and then flows through the drain 450 of the suction nozzle 45 and the hose 52 the disposal container 54.

If the ink printheads 80 have been rinsed sufficiently and then filled, the excess ink remaining in the cavities 40 must still be suctioned off. This is necessary because otherwise when the SA cap 4 is re-applied to the ink printing unit 8, the ink which has remained in the cavities 40 or caps 41 and possibly dried up again settles on the nozzle exit surface 800 of the ink printing unit and clogs it. So that in the event that ink still settles on the nozzle exit surface 800 of the ink printing unit 8, no print image disturbances can occur, in addition to sucking off the excess ink from the cavities 40 of the SA cap 4, the nozzle outlet surface 800 of the ink printing unit 8 after each flushing and filling process when driving out the printer carriage 7 from the service and rest area according to FIG.

Sucking off the excess ink from the suction openings or cavities 40 of the SA cap 4 begins with the ventilation valve being opened again during the pumping process. The air sucked in thereby presses the ink out of the rubber insert 41 and the recesses 40. In order that the ink can flow better between the liquid-absorbing insert 42 and the rubber insert 41 through the second passage opening 416, the transverse ribs 413 projecting into the rubber insert 41 are on the tub base 412 arranged. In addition, to prevent the air flowing through after emptying a single cap 41 from making it possible to further empty the adjacent other caps, the sieve 48 is constructed capillary. The capillarity of the sieve 48 arises in that the sieve 48 for a total pressure in the SA cap 4, for example 500 mbar has a fine-meshed sieve structure with very small holes, the z. B. each have a diameter of 16 microns. If the pressure applied to the screen 48 is, for example, less than or equal to 50 mbar, the air on the screen 48 is blocked. In order to be able to influence this barrier pressure on the screen 48, the outlet 450 of the suction nozzle 45 is dimensioned such that the outlet 450 acts as a throttle for the ink sucked out of the ink print heads 80. For example, a typical diameter of the drain 450 is 8/10 mm.

In order to maintain the barrier pressure, the pressure at the drain 450 must be at least so great that a differential pressure to the total pressure in the SA cap 4 is less than the barrier pressure for the air on the screen 48. At the predetermined barrier pressure of 50 mbar and the total pressure in the SA cap 4 of 500 mbar, the pressure at the drain 450 must be greater than 450 mbar. Since the pressure at the drain 450 is largely determined by the flow velocity of the ink, the pressure at the drain 450 changes depending on the ink in the SA cap 4. The pressure drop at the drain 450 associated with decreasing flow velocity is just the same chosen that when the cavities 40 and the rubber inserts 41 are completely emptied, the differential pressure exceeds the predetermined barrier pressure for the sieve 48 and thereby tear off the capillaries in the sieve 48.

During longer printing pauses of the ink printing device 1, the SA cap 4 is docked onto the ink printing heads 80 with the ventilation valve open. The ink soaked in the ink 42 ensures sufficient air humidity at the nozzle outlet openings of the ink printing unit 8 during the printing pause, so that evaporation and drying of the ink in the ink printing heads 80 is prevented.

FIG. 18 shows a top view of the detailed structure of a second embodiment of the SA cap 4 with four trough-shaped rubber inserts 41a integrated into an SA cap 4a for the separate suction of the ink from the nozzle outlet openings of the ink print heads 80. In contrast to the SA cap 4, the SA cap 4a does not require the controlled supply of air via the ventilation valve and the ventilation nozzle 43. Characteristic of the construction of the SA cap 4a are four double chambers 40a of the same size, arranged uniformly distributed on the SA cap 4a, each of which is covered over the entire area by a trough bottom 412a of the trough-shaped rubber insert 41a. The trough-shaped rubber insert 41a has a sealing lip 410a, which surrounds a trough opening 411a of the rubber insert 41a and, when the SA cap 4a is docked, is pressed against the ink printing unit 8 and thereby hermetically seals the nozzle outlet openings of the ink printing heads 80. As in the case of the SA cap 4, a liquid-absorbing insert 42a is introduced through the tub opening 411a into the tub-shaped rubber insert 41a. The double chamber 40a consists of an ink chamber 401a and a pressure compensation chamber 403a. The ink chamber 401a is connected to a drain 450a of a suction nozzle 45a via a channel system arranged in the SA cap 4a. A hose 52a, which transports the ink sucked off from the SA cap 4a to the disposal container 54, is in turn placed on the suction nozzle 45a. A slit valve 420 is arranged in the trough bottom 412a so that the ink sucked in by the ink printheads 80 can also enter the ink chamber 401a from the trough-shaped rubber insert 41a. The slit valve 420 is realized, for example, in that the trough bottom 412a, which is designed as a membrane film, is cut in one or more times. If the SA cap 4a is docked to the ink printing unit 8 and ink is subsequently sucked out of the nozzle outlet openings of the ink printing heads 80, the ink, after the insert 42a is saturated with ink, passes into the ink chamber 401a via the slit valve 420 which opens in the suction direction and from there through the drain 450a of the suction nozzle 45a into the disposal container 54. A flow back of the ink once passing through the slit valve 420 is no longer possible because the lobes of the slit valve 420 open against the suction direction through the insert 42a be prevented. This prevents undesired color mixing in the region of the trough-shaped rubber insert 41a and consequently print image disturbances in the subsequent printing process.

The pressure compensation chamber 403a, which is separated from the ink chamber 401a by an intermediate wall 421, is connected to the rubber insert 41a by a passage opening 415a let into the trough bottom 412a. An air overpressure which arises when the SA cap 4a is docked onto the ink printing unit 8 is compensated for through the passage opening 415a, so that the meniscus formed by the capillary-built ink printing heads 80 at the nozzle outlet openings is retained.

FIG. 19 shows a section through the SA cap 4a according to FIG. 18 along a section line XIX ... XIX. The SA cap 4a is then constructed from a carrier part 46a and a cover 47a. The ink chamber 401a and the pressure compensation chamber 403a are embedded in the carrier part 46a. While the ink chamber 401a is formed like a blind hole, the pressure compensation chamber 403a completely penetrates the carrier part 46a. The pressure compensation chamber 403a is partially drilled out on the side of the SA cap 4a opposite the sealing lips 410a, as a result of which a step 422 is created. In this gradation 422, a hollow film bubble 423, which acts as a pressure compensation membrane, is clamped with the aid of a clamping device 424. The clamping device 424 consists of an O-shaped ring 425 arranged in the step 422, onto which the film bubble 423 is clamped with the aid of a perforated disk 426. The film bubble 423, which acts as a pressure compensation membrane, reacts to changing air pressure conditions in the SA cap 4a by increasing or reducing the volume in the SA cap 4a. If the SA cap 4a is docked to the ink printing unit 8, for example, an overpressure is created in the SA cap 4a, through which the film bubble 423, compensating for the excess pressure, changes from a state E to a state F. The adaptation of the film bubble 423 to the respective pressure conditions in the SA cap 4a also works when the SA cap 4a is exposed to temperature fluctuations. In addition, the film bubble 423 is made of a non-diffusible or weakly diffusing material, so that the nozzle outlet openings of the ink print heads 80, when the ink printing device 1 is not in operation and the SA cap 4a is docked to the ink printing unit 8, are optimally protected against drying out.

FIG. 19 also shows how the trough-shaped rubber insert 41a is arranged above the ink chambers 401a embedded in the carrier part 46a and the pressure compensation chamber 403a and is thereby clamped between the carrier part 46a and the cover 47a. For this purpose, the cover 47a is drilled out in the periphery of the trough opening 411a of the rubber insert 41 and is welded onto the carrier part 46a, put over the carrier part 46a.

20 to 29 show how the SA cap 4 according to FIG. 2, represented by the centering fingers 33, 34 for a first service position of the ink printing unit 8 (FIG. 20 to FIG. 24) and for a second service position of the ink printing unit 8 (FIG 25 to FIG. 29) from the state lifted from the ink printing unit 8 (FIG. 20 and FIG. 25) is docked to the ink printing unit 8 in the exact position (FIG. 22 and FIG. 27) and also returns from the docked state to the initial state in the exact position (FIG. 24 and FIG 29).

In the RD station 6, which is arranged stationarily in the ink printing device according to FIG. 1, considerable tolerances occur between the ink printing unit 8 and the SA cap 4 of the RD station 6, which hinder precise and sealing docking. The problem is exacerbated when the RD station 6 is not allowed a separate parking position, but is located within the overshoot range UEB of the printer carriage 7 carrying the ink printing unit 8, which results from the write operation. For the above-mentioned service treatments of the ink printing unit 8 by the RD station 6, the ink printing unit 8 can come to a standstill at various points within the overshoot range. For the SA cap 4, this means that, before docking to the ink printing unit 8, it must first be brought into the position of the nozzle outlet openings of the ink printing heads 80 in order to be able to carry out the service treatments. In a first possible embodiment, this can be accomplished by the centering fingers 33, 34 according to FIGS. 20 to 29. For this purpose, the centering fingers 33, 34 tapering to an acute angle, as shown in FIGS. 22 and 27, plunge into the centering window 81 of the ink printing unit 8, as in FIG. For the service treatment of the ink printing unit 8, the printer carriage 7 carrying the ink printing unit 8 can remain between an extreme right and an extreme left service position.

In order to clarify the problem that arises when docking the SA cap 4 to the ink printing unit 8, the following considerations should be made.

If the printer carriage 7 remains for a first service treatment of the ink printing unit 8, for example in its extreme left position, the SA cap 4 follows this position through the centering finger 33 which dips into the centering window 81 of the ink printing unit 8 and docks onto the ink printing unit 8 . When the first service treatment has ended, the SA cap 4 lifts off the ink printing unit 8, returns to the original starting position and thereby releases the ink printing unit 8 for a new writing process. If the printer carriage 7 comes to a standstill at its rightmost service position for a second service treatment of the ink printing unit 8, the SA cap 4 must now be moved the entire distance between the leftmost and rightmost service position of the printer carriage 7 in order to to dock the inkjet 8. The same distance must be covered by the centering finger 33 in order to allow a precise docking. Characterized in that the centering finger 33 is formed at an acute angle, self-locking when immersing the Centering finger 33 avoided in the centering window 81 of the ink printing unit 8. On the other hand, with a centering finger 33 tapering to an acute angle, the SA cap 4 can only be docked to the ink printing unit 8 in an accurate position without additional measures if a centering path a is not too long for an exact docking of the SA cap 4.

In order to take this problem into account, a second centering window 61 is provided in the RD station 6 according to FIGS. 20 to 29 for the centering finger 34. The associated centering of the SA cap 4 on both sides has the consequence that the SA cap 4 is always docked from a defined starting position to the ink printing unit 8 for every service treatment even when the printer carriage 7 is in extreme service positions and when it is lifted off into this starting position again returns. If the centering window 61 of the RD station 6 is in the middle of the middle service position of the printer carriage 7, then the centering path a for the SA cap 4 and the centering fingers 33, 34 is also halved. The centering finger 33, 34 again be formed with an acute angle and thereby the risk of self-locking of the centering finger 33, 34 when immersed in the first centering window 81 or in the second centering window 61 is reduced. The self-locking occurs in particular when both the centering fingers 33, 34 and the first centering window 81 and the second centering window 61 are made of plastic.

Based on FIG. 2, FIG. 30 shows, based on a second RD station 6b, a second possible embodiment, such as an SA cap 4b made of a central position biased by two springs 38, 39 with a spring force F3 or F4, relative to a housing wall 100b Supporting structure 10b for any service position of the ink printing unit 8 can be docked onto the latter in a precisely positioned manner. Due to the highly precise mechanical processing of the inside, the housing wall 100b again serves as a reference edge both for the pivot lever 3b which can be displaced laterally on an axis 30b and for the one in one Service position moving printer carriage 7 carrying the ink printing unit 8. If the printer carriage 7 comes to a standstill for various service treatments once at the extreme left and another time at the extreme right service position, a centering finger 33b arranged on the swivel lever 3b can move into a third, Immerse the centering window 81b (not shown in FIG. 30) of the ink printing unit 8.

FIG. 31 shows a top view of the SA cap 4b docked on the ink printing unit 8, the immersion of the centering finger 33b in the centering window 81b. Because the SA cap 4b is docked for each service treatment of the ink printing unit 8 from the middle position to the ink printing unit 8 in an exact position, an angle β, which indicates the angularity of the centering finger 33b, is compared to an SA cap 4b without a defined starting position around it Half smaller.

FIG. 32 shows a side view of the RD station 66 according to FIG. 30. So that the centering finger 33b can dip into the centering window 81b, the pivot lever 3b is pivoted about the axis 30b for a pivot angle α. The swivel angle α is fixed by design-related requirements for the RD station 6b. For this reason, the swivel angle α cannot be increased in order to decrease the angle β and thereby make the centering finger 33b more acute.

Reference symbol list

1

Ink printing device

2nd

Switch coupling

3, 3b

Swivel lever

4, 4a, 4b

Suction and cover cap (SA cap)

5

Bellows pump

6, 6b

Cleaning and sealing station (RD station)

7

Printer carriage

8th

Ink printing unit

9

Platen roller

10, 10b

Structure

20th

Cam disc

21

Wheel

30, 30b

first axis

31

Lever upper part

32

Lower lever part

33, 33b

first centering finger

34

second centering finger

35

second axis

36

first spring

37

second spring

38, 39

feather

40

Cavity, recess, suction opening

40a

Double chamber

41, 41a

trough-shaped rubber insert

42, 42a

liquid-absorbing insert

43

Ventilation nozzle

44

Bearing journal

45, 45a

Extraction nozzle

46, 46a

Carrier part

47

Cover plate

47a

cover

48

Sieve

49

Catch basin

50

Linkage

51

Bellows

52, 52a

tube

53

Air hose

54

Disposal container

55

Ventilation valve

60

Pressure plate

61

second centering window

70

Guide rod

71

flexible traction device

72

Pulley

73

Electric motor

80

Ink printhead

81

first centering window

90

Drive device

91

transmission

100, 100b, 101, 102

Housing wall

200

Crank pin

201

inner cam track

202

outer cam track

203

Switch tongue

204

Board

310, 311

Swivel arm of the lever upper part

312, 313

Support arm of the lever upper part

314

Cross strut

315

-shaped recess

316

Middle part of the lever upper part

317

pocket-shaped shape

318

Spherical cap

319

Long hole

320

Lever arm of the lower lever part

321

Secondary arm of the lower lever part

322

first recess

323

second recess

324

third recess

400

first chamber, recess

401

second chamber, suction channel

401a

Ink chamber

402

third chamber, fastening opening

403

fourth chamber, pressure equalization channel

403a

Pressure compensation chamber

410, 410a

Sealing lip

411, 411a

Tub opening

412, 412a

Tub floor

413

Cross rib

414

web

415, 415a

first passage opening

416

second passage opening

417

funnel-shaped nozzle

418

knob-shaped extension

419

ledge formed like a brim

420

Slit valve

421

Partition

422

gradation

423

Foil bubble

424

Clamping device

425

o-shaped ring

426

Perforated disc

430

Air cannula

450, 450a

Drain

460

partition wall

461

first opening (hole)

462

second opening (hole)

463

third opening (hole)

464

oval-shaped recess

465

trough

470

Recess, extraction channel

471

Recess, stop

730

second drive pinion

800

Nozzle exit surface 900 first drive pinion

A, B, C, D

Printer carriage conditions

E, F

States of the bubble

FROM

Work area of the printer carriage

DB

Pressure range

DM

Torque

DZ

Pressure zone

FA

Pressing force

FG

Balance power

Fl, F2, F3, F4

Spring force

KM

Overturning moment

UEB

Overshoot range of the printer carriage

a

Centering path

x

Step distance

Δx

Air gap

y

Distance between the openings

α

Swivel angle

β

angle

Claims (17)

Device for the exact docking of a cleaning and sealing station / RD station (6, 6b) to an ink print head (8) which can be moved line by line in an ink print device (1) with the following features: a) the RD station (6, 6b) is arranged in the range of movement of the ink print head (8) and is coupled to a pivoting device (31) for pivoting the RD station (6, 6b) to the ink print head (8), b) the RD station (6, 6b) is laterally displaceably mounted in a predetermined catch area (a) with respect to a docking position of the ink print head (8), c) Adjustment elements (33, 81) are assigned to both the RD station (6, 6b) and the ink print head (8), such that when the RD station (6, 6b) is pivoted to the ones located in the area of the docking position Align the print head (8), the adjustment elements (33, 81) and the RD station (6, 6b) on the print head (8). Device according to claim 1, characterized in that the adjusting elements are designed as centering fingers (33, 34) tapering to an acute angle with the associated centering window (81, 61). Device according to claim 1 and 2, characterized ge k ennzeichn et that a fixed positioning means (61) is arranged in the capture range (a) of the RD station (6, 6b) in a decoupled from the ink print head (8) state of the RD Station (6, 6b) the RD station (6, 6b) is positioned in a predeterminable starting position. Device according to claim 3, characterized by two counter-directed centering fingers tapering at an acute angle (33, 34), a first centering finger (33) of which moves the RD station (6, 6b) in the direction of the ink print head (8) into a first centering window (81) of the ink print head (8) before the RD Station (6, 6b) is coupled to the ink print head (8) and of which a second centering finger (34) when moving the RD station (6, 6b) in the opposite direction into a second stationary area in the capture area (a) of the RD station ( 6, 6b) immersed centering window (61). Apparatus according to claim 3, characterized by a centering finger (33b) tapering at an acute angle in the direction of the ink print head (8), which is defined by two of the RD station (6, 6b) in the defined starting position in relation to a reference edge (8) common to the ink print head (8). 100b) holding spring forces (F3, F4) are pre-positioned and when moving the RD station (6, 6b) in the direction of the ink print head (8) self-adjusting, a third centering window (81b) is inserted into the ink print head (8). Apparatus according to claims 1 to 5, characterized in that the pivoting device has a pivoting lever (2) which is constructed in two parts for decoupling a pivoting and sideways movement which can be carried out on the pivoting lever (3). Apparatus according to claim 6, characterized in that the pivot lever (3) has a lower lever part (32) which is pivotally mounted on an axis (30) and is coupled to the movement device (20, 21, 37). Apparatus according to claim 6 or 7, characterized in that the pivoting lever (3) has an upper lever part (31) which is pivotally mounted and displaceable relative to the lower lever part (32) on the axle (30) and is connected to the lower lever part (32). Apparatus according to claim 8, characterized in that the lower lever part (32) is connected to the upper lever part (31) via a lever arm (320) belonging to the lower lever part (32), which engages in a pocket-like shape (317) of the upper lever part (31). Device according to one of claims 6 to 9 , characterized in that the swivel lever (3) has a holding device (312, 313, 314, 315, 318, 319) for a suction and cover cap (4, 4a, 4b) of the RD station (6 , 6b), with which the suction and cover cap (4,4a, 4b) aligns itself automatically with a pressure force (FA) for the precise coupling to the ink print head (8). Apparatus according to claim 10, characterized in that the holding device (312, 313, 314, 315, 318, 319) is arranged in the upper lever part (31) of the swivel lever (3). Device according to claim 10 or 11, characterized in that the holding device (312, 313, 314, 315, 318, 319) has a T-shaped recess (315) in two oppositely arranged support arms (312, 313) of the lever upper part (31) , in which the suction and cover cap (4, 4a, 4b) is rotatable and displaceable in the direction of the pressing force (FA). Device according to claim 10 or 11, characterized in that the holding device (312, 313, 314, 315, 318, 319) has an elongated hole (319) in the two oppositely arranged support arms (312, 313) of the lever upper part (31) which the suction and cover cap (4, 4a, 4b) is rotatably arranged and displaceable in the direction of the pressing force (FA). Device according to one of claims 10 to 13, characterized in that the holding device (312, 313, 314, 315, 318, 319) on a cross strut (314) between the support arms (312, 313) has a spherical cap (318), via which the for coupling the suction and cover cap (4, 4a, 4b) necessary pressure force (FA) is transmitted to the ink print head (8). Device according to one of claims 1 to 14, characterized in that the pivoting device is assigned a motor-driven cam disk (20) with cam tracks (201, 202) separated from one another in two stages, which merge into one another at two points on the cam disk (20). Apparatus according to claim 15, characterized in that an impeller (21) is arranged on the cam disc (20) that is pressed against the cam disc (20) by a spring force (F2) acting in the radial direction towards the cam disc (20) and is guided through the cam tracks (201, 202). Apparatus according to claim 15 or 16, characterized in that a switch tongue (203) is arranged on the cam disc (20), which by controlling the orbit of the impeller (21) around the cam disc (20) as a function of a predetermined direction of rotation of the motor-driven Cam disc (20) the suction and cover cap (4, 4a, 4b) on the ink print head (8) or uncoupled.

Images