The present invention relates to the exclusive domain of processing mail, and more particularly to a printing process and device in a franking machine of inkjet type.
An inkjet franking machine is disclosed in U.S. Pat. No. 5,083,153. Inkjet printing renders franking machines highly versatile, in particular when it is question of printing on the articles for mailing postal indicia comprising both variable characters, such as the numerical values of an amount of postage, and arrangements of colours such as those of advertizing logos.
Due to the dimensions of the indicia to be printed and those of the bars (or casings) of ink ejection nozzles currently available on the market, it has proved that printing of such indicia can be carried out at the present time under acceptable economic conditions, only from two offset rows of ejection nozzles. The printing faults (particularly connection in the median part) due to the relatively imprecise positioning of these rows (however, Applicants have proposed in French Applications FR 2 724 591 and FR 2 724 592 appropriate methods for adjusting in situ before printing in order to obtain a perfect alignment of the nozzles of the two boxes), accentuated by the shocks provoked by the conveyor rollers on the article for mailing during transport thereof, certainly raise acute problems in mail processing. In effect, in this particular technical domain, the indicia includes critical postage data such as the amount of franking which represents a monetary value and no fault affecting this value, however small, can be accepted by the Postal Service. Moreover, with the introduction of so-called “intelligent” indicia, integrated coded information, there is the problem of authentication and checking of this information. In effect, verification and validity of the indicia lies with the recognition of this coded information as well, possibly, as other information shown clear on the indicia (date or machine number for example) and an error in reading resulting from misaligned connections may have damaging consequences as to the validity finally recognized of the article for mailing.
It is an object of the present invention to overcome the problems set forth hereinabove by proposing an improved printing process which avoids, at least at the level of the critical postal data, misaligned connections of the ejection nozzles of the printing device of an inkjet franking machine. One object of the invention is to eliminate such misaligned connections without notably increasing the structure of the printing device. Another object of the invention is to facilitate subsequent recognition of the critical postal data by the Postal Service.
To that end, the invention relates to a process for printing postal indicia on a mail piece to be franked, displaced with respect to a printing device of an inkjet franking machine in a direction of displacement F, the postal indicia comprising at least an amount of franking, a date of deposit and an authentication code and the printing device comprising a plurality of nozzles for ejecting droplets of ink disposed in two rows extending transversely to the direction of displacement and spaced from each other by a distance D in this direction and a control means for selectively controlling the ejection of these ink droplets as a function of the indicia to be printed, process characterized in that each of the critical postal data, such as the amount of franking, the date of deposit or the authentication code is printed from one row of nozzles.
This process eliminates the misaligned connections previously affecting the date of deposit and the amount of franking, the reliability of the reading of these data consequently being increased. In addition, taking into account the fact that the critical postal data can no longer be disposed in the zone of connection of the two rows of ejection nozzles, an adjustment in situ of the alignment is no longer indispensable.
According to an advantageous characteristic, at least the end nozzles of the two rows of ejection nozzles, disposed at the level of a median part of the postal indicia, are de-activated, in order to avoid a possible overlapping during printing.
Certain determined ejection nozzles are selectively de-activated in order to allow printing at a lower resolution of the data other than that relative to said critical postal indicia. Thanks to this characteristic, the speed of printing is increased and the cost of the indicia is decreased by reducing the quantity of ink ejected.
The invention also relates to an inkjet printing device of a franking machine intended to print postal indicia on a mail piece to be franked, displaced with respect to this device in a direction of displacement F, the postal indicia comprising at least an amount of franking, a date of deposit and an authentication code and the printing device comprising a plurality of nozzles for ejecting ink droplets, disposed in two rows extending transversely to the direction of displacement, these two rows of nozzles being spaced apart from each other by a distance D in this direction and a control means for selectively controlling the ejection of these ink droplets as a function of the postal indicia to be printed, said device being characterized in that said control means is arranged so that, during printing, each of the critical postal data such as the amount of franking, the date of deposit or the authentication code, is printed from one row of nozzles.
At least the end nozzles of the two rows of ejection nozzles disposed at the level of a median part of the postal indicia are preferably de-activated in order to avoid an overlapping during printing. Certain determined ejection nozzles are advantageously de-activated to allow a print at a lower resolution of the data other than that relative to said critical postal data.
The invention will be more readily understood on reading the following description given by way of non-limiting example, with reference to the accompanying drawings, in which:
Referring now to the drawings, and firstly to
This printing device comprises two casings 20, 21 each comprising a row of nozzles R1, R2 (the nozzles are represented by crosses), these two rows of nozzles being mounted in the printing device 2 so that they extend transversely to the direction of displacement F, the two casings being offset with respect to each other both transversely and longitudinally with respect to this direction F (by a distance D).
The presence of these two casings is imposed at the present time for technical and commercial reasons. In effect, the dimensions of the standard, and therefore low-cost, rows of nozzles are today limited to only half an inch (12.7 mm) while the height of postal indicia is currently close to 25 mm. These ink-jet printing casings have variable resolutions currently ranging from about 200 nozzles per inch (viz. one nozzle every 0.127 mm) to 600 nozzles per inch (1 nozzle every 0.042 mm), which is perfect for printing postal indicia.
The arrangement of the two casings 20 and 21 is such that the distance between the last nozzle B′128 (the uppermost one in
The franking machine further comprises a control means 3, advantageously comprising a microprocessor and a programme recorded in a memory (not shown) associated therewith, which is arranged in order selectively to control (as a function of the postal indicia to be printed) the chronological succession of the ejections of droplets of ink of the different nozzles, in response to a clock signal 22, 23 synchronized or not with a speed of displacement of the article of mail beneath the printing head 2, so that it is possible to produce dots on this article which join each other with slight overlap along straight lines parallel to direction F.
In order to print a linear mark transverse to direction F and which extends over almost the whole height H of the indicia 10 (like the bar of the letter P shown in
However, due to the tolerances of the casing designers, the distance D varies from one printing device to the other and it is, in principle, necessary to adjust it after assembly of the casings 20 and 21 in the franking machine, for example by resorting to the methods of adjustment before printing mentioned above, developed by Applicants.
Certain of these different postal franking data are critical, in that their non-recognition, or false recognition, may cause a considerable prejudice both against the Postal Service and the user. Such data concern the amount of franking which represents a monetary value, the date of deposit which must correspond to the effective remittance of the article to the Postal Service, the code of verification which allows control of the optical reading and of the coded authentication information which guarantees the integrity of the postal data forming the indicia.
As shown in this
According to the invention, and as illustrated in
Moreover, in order to facilitate recognition/control of these critical postal data, they are provided to be printed at a resolution higher than a standard resolution of print of the other postal data of the indicia. The information thus provided at a high resolution presents a better contrast and stands out better from the indicia, which facilitates optical reading thereof.
Such modification of the print resolution may be obtained in two orthogonal directions T and F (cf.
Therefore, with RT=300 dpi and RT=450 dpi, it becomes possible to print the different postal data, critical or not, or information, at the following three resolutions:
It will be noted that the reduction of the resolution presents the advantage of allowing an increase in the overall speed of printing of the indicia and a reduction in the consumption of ink (consequently with a reduction in the cost price of printing an indicia) as well as a reduction in the time for this ink to dry (which avoids smudging with certain types of support).
Number | Date | Country | Kind |
---|---|---|---|
98 13500 | Oct 1998 | FR | national |
Number | Name | Date | Kind |
---|---|---|---|
4649266 | Eckert | Mar 1987 | A |
4862386 | Axelrod et al. | Aug 1989 | A |
5070345 | Lahut et al. | Dec 1991 | A |
5769550 | Brand et al. | Jun 1998 | A |
5946011 | Kanaya | Aug 1999 | A |
Number | Date | Country |
---|---|---|
0 076 948 | Apr 1983 | EP |
0 702 334 | Mar 1996 | EP |
0 702 335 | Mar 1996 | EP |
0702334 | Mar 1996 | FR |