EP0719645B1 - Ink jet printer - Google Patents

Description

The present invention relates to a jet printer ink provided with a movable carriage arranged so as to ability to receive interchangeable print head with at least one print head of a second type, printer with maintenance station having at least two types of caps intended for be applied by an actuating mechanism on the head of the type for which they are intended.

In inkjet printers, it is to protect the ink ejection nozzles from the print head, when it is in the position rest for an extended time between periods in order to avoid drying of the ink leading to blockage of the nozzles.

To this end, a nozzle is applied against the nozzle plate. hood that maintains a certain humidity level.

The device which is the subject of the present invention applies to a printer with a printhead interchangeable plug-in in the mobile carriage printing.

Different types of heads can be plugged into the carriage, for example a black ink head or a head with multicolored ink.

To avoid soiling, via the cap, of a head by the ink of another head, for example of a head color with a black head, caps are provided respective for each type of plug-in head.

US Patent 5,155,497 describes a maintenance station for a printer of this type. This station includes a support rotating 180 ° around a parallel axis the direction of movement of the carriage and on which two caps are mounted in opposite positions via two longitudinally movable slides along this direction of travel of the carriage mobile. After detecting the type of mounted print head on the carriage, the rotating support rotates the slide and the cap corresponding to the head, the carriage then drives the slide longitudinally to apply the cap against the plate of the nozzles.

This maintenance station is composed of a large number of parts and is of a complicated construction. In besides it cannot be integrated in printers already existing.

The object of the present invention is to remedy these disadvantages and the invention is characterized for this purpose by the fact that the maintenance station understands at minus a main cap mounted on a movable support main and intended to cooperate with said printhead interchangeable and at least one additional cap mounted on at least one secondary mobile support and arranged to be interposed between the main cap and the second type print head.

By these measures, we obtain a very compact construction and simple and the possibility of easy adaptation on existing printers originally designed for a single type of print head.

According to a favorable embodiment, the print head of the second type has at least one element of form different from the interchangeable print head, this element being arranged to control movement secondary mobile support to insert one or more of the additional caps between the main cap and the second type print head when the carriage equipped with the second type print head is moved to the maintenance station.

The shape of the print head thus determines the selection of the cap which will be applied against the nozzles, which allows simple and safe operation, while having a construction of a low cost price.

Favorably, the secondary mobile support (s) are slidably mounted on the printer in one direction parallel to the direction of travel of the carriage mobile, the printer comprising an actuated lever mechanism by said element of different shape and arranged so as to move the secondary mobile support (s) against the action of an elastic member to interpose at minus one additional cap between the main cap and the second type print head, when the cart is moved to the maintenance station.

These features help simplify construction of the maintenance station and allow a easy adaptation of existing multi-head stations and as many caps.

Advantageously, the application of or one of the additional caps against the print head of second type plugged into the carriage is carried out by the pushing the main cap towards this head printing.

These features allow safe operation and a space-saving construction of a number of components reduced.

Other advantages emerge from the characteristics expressed in dependent claims and description setting out the invention below in more detail at using drawings which represent schematically and at as an example an execution mode.

Figures 1a) to 1d) schematically illustrate the principle underlying the invention.

Figure 2 is a side view of the embodiment shown during printing.

Figure 3 is a front view of Figure 2, some elements not shown.

Figure 4 is a side view of the embodiment shown with the print head in the rest position in the maintenance station.

Figure 5 is a front view of Figure 4, some elements not shown.

Referring to Figure 1a, a maintenance station 3 of a printer includes a main mobile support 4 on which a cap is slidably mounted main 5 secured to a cap holder 6. A head interchangeable printer 8 plugged into an east carriage moved to a position in the maintenance station where it is arranged opposite the main cap 5. This the latter is then applied against the part nozzles front of the print head 8 to prevent drying ink, as shown in Figure 1b).

The printer is arranged to receive at least one another type of print head 10 having a shape or an element of different shape 11 (FIG. 1c)). This element 11 serves as a selection organ for controlling the placement of an additional cap 12 which is interposed between the main cap 5 and the front part of the print head 10, when the latter is mounted on the carriage. Then apply the cap additional 12 against the print head 10 is carried out by pushing the main cap 5 towards of the print head 10. When the print head interchangeable 8 is mounted on the carriage, the cap additional 12 remains stationary in a position laterally offset as shown in Figures 1a and 1b.

The main cap 5 with its cap holder 6 are resiliently mounted on the support 4, on which they slide with a predetermined stroke delimited by stops not shown, thanks to a spring 14 which is more or less compressed depending on whether the additional cap 12 is inserted or not.

The construction of this embodiment is explained in more detail with reference to Figures 2 to 5. Thus, to Figures 2 and 3, the carriage 20 carrying the print head interchangeable 8 slides on a shaft 21 and moves by a back and forth movement through a document to print it.

The maintenance station 3 is arranged laterally outside the printing area so as to cooperate with the carriage 20 and the print head 8 or 10 plugged into it cart. This maintenance station 3 comprises a chassis 24 on which is slidably mounted vertically the main mobile support 4 pulled by a spring 25 against a stop 26 (Figure 2). The main mobile support 4 carried the cap holder 6 and the main cap 5 which can be lowered, as illustrated in FIG. 3 in mixed lines to be applied directly against the interchangeable print head 8. Printer includes for this purpose an actuation mechanism 30 comprising a lever 31 articulated along a pivot 32 on the chassis 24. This lever 31 has a branch 33 intended to cooperate with a part 34 of the carriage 20 and a branch 36 arranged so as to cooperate with the main mobile support 4.

The actuation mechanism 30 also has a pinion 38 rotated by a motor not shown of the printer and who is likely to cooperate with a tooth 39 secured to the main mobile support 4 (figure 2).

When the carriage 20 is placed in the position of rest in maintenance station 3, its part 34 pushes against the branch 33 of the lever 31. This last, by pivoting on the chassis 24 urged by its branch 36 the main mobile support 4 down so to move it the distance necessary to engage the tooth 39 in the toothing of the pinion 38, as shown in Figure 3 in phantom.

After the truck stops in the maintenance station, the printer motor rotates the pinion 38 to resiliently apply the main cap 5 against the face of the nozzles of the print head 8.

Referring to Figures 4 and 5, the print head 10 of the second type can be plugged into the carriage 20 to the place of the head 8. The element of different shape 11 consists of a finger 11 intended to cooperate with a lever mechanism 42 for interposing the additional cap 12 between the main cap 5 and the print head 10.

This additional cap 12 is fixed on a support secondary mobile 44 pivotally and slidingly mounted on a shaft 45 fixed to the chassis 24. A spring 43 placed on this shaft requests the secondary mobile support 44 towards a rest position illustrated in Figures 2 and 3, in which the secondary cap 12 is is rotated by an angle of about 20 ° upwards by relative to the horizontal and to the left end of the tree 45.

The lever mechanism 42 includes a first lever 46 pivotally mounted at 47 on the chassis 24. It has a first branch 48 capable of cooperating with the finger 11 as a form element and a second branch 49 comprising a cleat 50 cooperating with a second lever 52 of the mechanism. This lever 52 is pivotally mounted at 53 on the chassis 24 and comes into contact with the cleat by a branch 54 and with the secondary mobile support 44 by a branch 55.

The second type print head 10 thus acts on the lever couple 46, 52 which transmit the movement of translation from the head to the secondary mobile support 44 to place the additional cap 12 opposite this printhead 10. The distance between the cap main 5 of nozzle surface 15 of head 10 is sufficient to allow free insertion of the secondary mobile support 44 and cap assembly secondary 12.

Then sliding the mobile support down main 4 is executed as described above. The support main mobile 4 then press the secondary mobile support 44 against the print head 10, the secondary cap 12 coming to rest against the nozzle surface 15. Following a print command, the the printer rotates the pinion 38 in the direction of clockwise in Figure 4 to bring the tooth 39 up. The carriage 20 can then leave the station maintenance and main mobile media and secondary are moved by the action of springs 25 and 43 towards the rest position illustrated in FIGS. 2 and 3.

It is understood that the embodiment described above is in no way limiting and that it can receive any desirable modifications inside of the framework as defined by claim 1. In in particular, the mechanisms controlling the intercalation of the secondary cap and lowering of movable supports could be done differently, for example without the intervention of levers by direct action of a part of the print head and the carriage on the support secondary and main mobile. We could also carry out with the same principle a variant allowing three or more different types of printheads. In this case, the secondary mobile support would include two or more caps whose respective positioning opposite the plug-in print head would be secured by different finger lengths of the print heads respective; the sliding stroke of the support secondary mobile would for example be controlled accordingly by the fingers provided on the print heads.

One or more caps could be connected by flexible tube to a suction pump allowing priming the print head or fitted with an absorbent pad the ink. The maintenance station may also be equipped with one or more flaps intended to wipe the front of the print heads. These flaps could be retractable or not on the main mobile support or on the chassis.

Claims (8)

1. An inkjet printer comprising a movable carriage (20) having an interchangeable printing head (8) with at least one printing head (10) of a second type, the printer comprising a maintenance station (3) having at least two types of covers (5,12) adapted to be applied by a driving mechanism (30) to the printing head of the type to which they are adapted, characterised by the fact that the maintenance station comprises at least a primary cover (5) mounted on a primary movable support (4) and adapted to co-act with said interchangeable printing head (8) and at least a supplementary cover (12) mounted on at least one secondary movable support (44) and adapted to be inserted between the primary cover (5) and the printing head (10) of the second type.
2. A printer according to claim 1, characterised by the fact that the printer head (10) of the second type comprises at least one element (11) of different shape as compared to the interchangeable printing head (8), this element (11) being adapted to control the movement of the secondary movable support (44) in order to insert the or one of the supplementary cover(s) (12) between the primary cover (5) and the printing head (10) of the second type as soon as the carriage (20) provided with the printing head (10) of the second type is displaced towards the maintenance station (3).
3. A printer according to claim 1 or 2, characterised by the fact that the supplementary cover(s) (12) is (are) of generally flat shape.
4. A printer according to claim 2 or 3, characterised by the fact that the secondary movable support(s) (44) is (are) mounted on the printer sliding in a direction parallel to the direction of the movement of the movable carriage (20), the printer comprising a lever mechanism (42) driven by the said element (11) of different shape and adapted to displace the secondary movable support (44) against the action of an elastic member (43) for inserting at least one supplementary cover (12) between the primary cover (5) and the printing head (10) of the second type, as soon as the carriage (20) is moved towards the maintenance station (3).
5. A printer according to one of the claims 2 to 4, characterised by the fact that applying the supplementary cover(s) (12) against the printing head of the second type (10) plugged onto the carriage (20) is done by the pressure of the primary cover (5) in the direction of this printing head (10).
6. A printer according to claim 5, characterised by the fact that the driving mechanism (30) is adapted to displace the primary movable support (4) towards the printing head (8, 10) plugged on the carriage (20) and comprises a pinion (38) intended to be rotationally driven by a printer engine and adapted to co-act with a projecting member (39) integral with the primary movable support (4), the driving mechanism (30) comprising at least one driving mechanism (31) adapted to co-act with the movable carriage (20) when the latter is displaced towards the maintenance station (3) for moving the primary movable support (4) from a first position in which the projecting member (39) is not in contact with the pinion (38) into a second position in which the projecting member (39) is engaged by the pinion (38) in such a manner that this latter one drives the primary movable support (4) towards the plugged-in printing head (8, 10).
7. A printer according to one of the proceeding claims, characterised by the fact that the primary cover (5) comprises an axial elasticity with respect to the primary movable support (4).
8. A printer according to claim 7, characterised by the fact that the primary cover (5) is mounted by the means of at least one spring (14) on the primary movable support (4).

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