EP2077531A1 - Franking system with built-in image sensor - Google Patents

Abstract

The device i.e. optical reader (26), has a support on which a contact image sensor (20A) is fixed, and arranged along a direction perpendicular to movement of a mail item (10) in a franking system. Movable fixation units fix the support on a structural part of the franking system so as to permit vertical displacement of the support around a Z-axis and to pivot the support at the same time around a longitudinal Y-axis and around a transverse X-axis. The fixation units include suspension arms (44A, 44B) articulated to an end on a common articulation axle (54) fixed to the structural part. An independent claim is also included for a franking system's element comprising a presser provided at right of a scanning device and for applying a mail item against the device.

Description

Field of the art

The present invention relates exclusively to the field of mail processing and more particularly relates to a postage system of which one of the modules constituting it, such as the mail item feeding module (feeder), the weighing module of mail items (postal scale), the print module of these mail items (franking machine itself), the folding and inserting module (folder / inserter) or any other independent module, includes a integrated images.

Prior art

It is well known that postal administrations or private carriers use complex scanning systems that allow for many control and monitoring applications, in particular the analysis of mail items and their sorting according to their destination. These systems are, however, particularly expensive and their volume is important, particularly because of the use of cameras. They are therefore really interesting for a sender only if it is required to handle large volumes of mail, such as a router. Indeed, in the context of a standard postage system disposed in the mail shipping room of a company and formed for example of a feeder, a postal scale, a franking machine and possibly a folder / inserter, the scanning of mail items using similar technologies is not an option.

For these conventional franking systems, it is necessary to use small sensors, type CIS (Contact Image Sensor), used today especially in the scanning units of photocopiers. Now, in these photocopiers, the thickness of the paper being relatively constant, low and uniform, the so-called CIS sensor is generally fixed.

It is quite different with a postage system. Indeed, the upper face of the mail items is not always flat, differences in thickness due to the contents of the mail piece or defects in shape due to conveying through the system can alter the quality of the digitization . In addition, the digitized area is relatively large, typically greater than 30 cm. Indeed, depending on the format of the mail item, the position of the address of the recipient is different and it is desirable to be able to scan not only this destination address but also the other visible information on the mail item (amount postage, address of the sender, etc.).

A first solution to these problems is given by the digitizing device specially adapted to the franking systems and illustrated in the patent application. FR 07 57285 filed in the name of the plaintiff. In this mobile device and no longer fixed, the conveyance of mail items is done keeping a common reference which is the underside of these mail items. Thus, whatever the thickness of the mail piece, its lower face will therefore pass into the system always in the same place.

This device gives overall satisfaction particularly for low or medium franking rates. On the other hand, for high speeds, it suffers from certain disadvantages coming mainly from the amplitude of the displacement of the sensor, which can then be a few tens of mm. Indeed, this sensor must move vertically by a value equal to the thickness of the mail piece (which can vary from 0.2 mm to more than 20 mm). But if the rates Postage and therefore scanning are important - they can go up to 5 articles per second - a rapid vertical displacement of the sensor causes vibrations which, besides being unfavorable to a good quality of digitization, can damage it. In addition, at high speed, when passing a mail item of large thickness (more than 15 mm) followed by a smaller thickness (a few mm), the sensor does not have time to return to its rest position to scan the second mail item.

Object and definition of the invention

The present invention therefore aims to overcome the aforementioned drawbacks by installing a so-called CIS sensor in a franking system that allows a correct scanning of the entire surface of the mail items, regardless of the format (business card format up to 'in the largest format) and the thickness of this mail item. An object of the invention is to allow this sensor to adapt to displacements and surface defects of the mail article, while allowing a digitization of sufficient quality to be able to use a character recognition software analyzing the images. digitized. Yet another object of the invention is to control the distance between the sensor and the article of pledge of a good quality of digitization. Another object of the invention is also to propose a feeding device which does not require a redefinition of its general architecture.

• un capteur d'images à contact (CIS),
• un support sur lequel est fixé ledit capteur, ledit support étant disposé selon une direction perpendiculaire à l'avancée des articles de courrier dans ledit système d'affranchissement et ayant un axe longitudinal Y et un axe transversal X, et
• un moyen mobile de fixation pour fixer ledit support sur une partie de structure dudit système d'affranchissement de façon à permettre un déplacement vertical dudit support (translation autour de l'axe Z) et son pivotement à la fois autour dudit axe longitudinal (rotation autour de l'axe Y) et autour dudit axe transversal (rotation autour de l'axe X).

These objects are achieved by a scanning device for postage meter system, comprising:

• a contact image sensor (CIS),
• a support on which is fixed said sensor, said support being arranged in a direction perpendicular to the advancement of articles mail in said franking system and having a longitudinal axis Y and a transverse axis X, and
• movable securing means for securing said support to a structural part of said franking system so as to allow vertical movement of said support (translation about the Z axis) and pivoting thereof both about said longitudinal axis (rotation around of the Y axis) and about said transverse axis (rotation about the X axis).

Thus, by this simple structure the sensor can move both vertically and rotationally along its longitudinal and transverse axes, which allows it to adapt to all thicknesses of mail items and to automatically scan mail items during their displacement.

According to a preferred embodiment, said movable fixing means comprises two suspension arms articulated at one end on a common axis integral with said structural part and at another end on a pivot axis fixed to said support, said pivoting about said axis transversal being provided by a set of connecting said first end.

According to another embodiment, said movable fixing means comprises a suspension arm articulated at one end on a common axis integral with said structural part and at another end on a ball joint secured to said support, so as to allow through said ball joint said pivoting both around said transverse axis and about said longitudinal axis, stops being further provided to prevent rotation during said vertical movement of said support.

Preferably, it further comprises a damping device for damping said vertical displacement of said support. Said damping device may be constituted by a single spring.

The said contact image sensor is formed of an integrated module comprising adjacent semiconductor detection cells, a collimation optics and a lighting system.

Depending on the space available, the scanning device can be mounted in an independent subset of the franking system or in one of the following subsystems of the franking system: feeder, postal scale, franking machine, folder / inserter .

The invention also relates to any element of a postage system comprising such a digitizing device and wherein said mail items are applied against said digitizing system by a pressing member arranged in the right of said digitizing system. Said pressure member is preferably mounted on springs or any other similar system for applying pressure on the mail piece.

Brief description of the drawings

• la figure 1 est une vue générale d'un système d'affranchissement auquel est appliqué l'invention,
• la figure 2 est une vue en coupe d'un premier mode de réalisation de l'invention,
• la figure 3 est une vue en perspective de l'ensemble capteur mis en oeuvre dans la figure 2,
• la figure 4 illustre le déplacement de l'ensemble capteur avec un article de courrier d'épaisseur variable,
• les figures 5A à 5C illustrent en coupe trois positions successives d'un article de courrier passant devant l'ensemble capteur de la figure 3,
• la figure 6 est une vue en coupe d'un second mode de réalisation de l'invention, et
• la figure 7 est une vue en perspective de l'ensemble capteur mis en oeuvre dans la figure 6.

The invention will be better understood in view of the following detailed description accompanied by illustrative and nonlimiting examples with reference to the following figures in which:

• the figure 1 is a general view of a franking system to which the invention is applied,
• the figure 2 is a sectional view of a first embodiment of the invention,
• the figure 3 is a perspective view of the sensor assembly implemented in the figure 2 ,
• the figure 4 illustrates the displacement of the sensor assembly with a mail piece of variable thickness,
• the FIGS. 5A to 5C illustrate in section three successive positions of an article of mail passing in front of the sensor assembly of the figure 3 ,
• the figure 6 is a sectional view of a second embodiment of the invention, and
• the figure 7 is a perspective view of the sensor assembly implemented in the figure 6 .

Detailed description of embodiments

The invention is based on the use of a qualified system of high reference in which the upper face of the mail piece, that is to say the face that is desired digitized, is always located in the same position that is the thickness of this mail item and therefore always goes to the same place in the system.

In such a system, the so-called CIS sensor is fixed on a mobile support which follows the deformations and displacements of the upper face of the mailpiece. The sensor is thus not arranged in a fixed position because the conveyance of mail items in the machine is not perfect, the upper face of these mail items is not always rigorously flat. It is therefore necessary to allow the sensor to move and rotate while keeping a small fixed distance between the sensor and the upper face of the mailpiece that is to be digitized because the depth of field of such a sensor is limited.

The figure 1 illustrates a franking system of mail items having, as is known and arranged upstream downstream in the direction of advancement of mail items 10: a module 12 for supplying mail items intended to receive a mail item; stack of mail items typically in bulk (ie of different sizes and weights) each having a destination address 10A and, in the illustrated example, an identifier 10B relating to a value added postal service; possibly a module 14 for selection and transport one by one of these mail items when the power module does not directly perform this individual selection; preferably a dynamic weighing module 16 for determining the weight and possibly the dimensions of each selected mailpiece and a printing module 18 for printing a postal imprint on each of the mail items thus selected one by one and weighed. The printing module is preferably, as is also known, connected to a server (not shown) of a dealer of this franking system itself connected to a server of a postal administration or a carrier private sector providing mail delivery (not shown).

In the exemplary embodiment illustrated, the franking system further comprises an independent optical reading module 20 comprising a sensor 20A advantageously linear type called "contact", arranged upstream of the dynamic weighing module (but a provision other is also possible), to acquire a digital image of the mail article 10 and extract at least the identifier 10B relating to the value-added service desired for this mail item and the address of the recipient 10A worn on the mail item. To do this, this image sensor is associated with barcode recognition and OCR recognition software. The printing module furthermore comprises an improved user interface 18A with a keyboard allowing the display on a screen 18B of all or part of the image of the article of mail thus digitized and, if necessary, the correction of the postal data. extracted from this image. The keyboard can be a physical keyboard interacting with a virtual keyboard screen 18B which is then advantageously tactile type or be replaced purely and simply by this touch screen. The printing module may also include storage means (not shown) of the database type for storing the image of the envelope thus digitized.

The figure 2 shows, in a first embodiment, a detail of the optical reading module 20 and in particular transport rollers formed for example of two adjacent sets of superimposed front transport rollers 22A, 22B and rear 24A, 24B for conveying mail items through the module. The lower rollers 22A, 24A of these two assemblies are mounted idle and movable vertically about axes of rotation 22C, 24C to adapt to the different thicknesses of the mail items and the upper rollers 22B, 24B are motorized and synchronously actuated by various known means of control and control necessary for their operation and that it is therefore unnecessary to describe in more detail.

According to the invention, in order to allow an automatic processing of the mail items and not to increase the dimensions of the module, it is proposed to interpose between these two sets of transport rollers a movable optical reading assembly 26 comprising the sensor 20A and allowing in connection with a processing means 28 scanning and automatic recognition of information carried by these mail items. This set will be mobile to follow the upper surface of the mail item that is not uniform and thus ensure by its movement and its privileged position in the system, an optimal scanning quality regardless of the thickness of mail items , especially in the presence of thick envelopes. The triggering of the digitization and the processing of the data by the processing means 28 can be advantageously synchronized from a detector (not shown) of a front of each of the mail items. This digitization can also be carried out continuously, the synchronization then taking place by a detection of change of gray level or change of color appearing systematically when moving from one envelope to another.

The perspective of figure 3 shows more precisely the movable optical reading assembly 26 comprising the sensor 20A mounted in a support 30 in the form of a bridge, having a longitudinal axis (Y axis) and a transverse axis (X axis) and having at the base of its two walls longitudinal 32, 34 respectively an upstream deflector 32A and a downstream baffle 34A. The sensor is fixed to the support for example by two screws 36A, 36B each passing through two lateral flanges 38A, 38B themselves fixed by screws 40A, 40B, 40C, 40D on the upper wall 42 of the support 30. The lower surface of the sensor is maintained in alignment with the baffles to provide plane contact with the upper surface of the mailpieces. However, a Z-axis shrinkage of not more than 0.5mm is tolerated for a sensor whose depth of field does not exceed 2mm. The upstream deflector has an inclined leading edge 32A to allow a progressive support of the mail item on the support and the downstream baffle has a heel 34A which maintains a desired distance between the mail item and the mailpiece. sensor. In the illustrated example, the sensor / deflector assembly is supported by two suspension arms 44A, 44B each articulated at a first end on an individual pivot axis 46A, 46B mounted between two lugs 48A, 48B; 50A, 50B extending from the upstream longitudinal wall 32 of the support and at a second end on a common hinge pin 54 integral with the module frame. These two arms make it possible to lock longitudinally and transversely the mobile support and the sensor which it envelopes, that is to say to prohibit them any translation along the axes X and Y or rotation along the axis Z, the assembly being able to then freely move in translation only in the vertical direction Z and in rotation along the X and Y axes, the independence of the two arms that are mounted with clearance allowing the sensor to pivot freely around its transverse axis (rotation around the X axis). Thus, the sensor can adapt to the shape of the mail piece (and in particular a variable thickness according to its width) as shown by the two positions of the figure 4 , one having been rotated about the X axis about 10 ° relative to the other, which is particularly advantageous when one wants to scan a document of great width.

Of course, the movable support can be linked to the module frame by any other mechanical connection that the two suspension arms described above subject to leaving a degree of freedom of vertical movement. Thus, a device comprising simply two springs (or two damping devices) suspended from the frame and retaining the upper wall of the support is also perfectly suitable.

The sensor is advantageously a linear-type contact image sensor (CIS) the length of which is intended to scan at least one width of a mail item covering the postal fingerprint and the destination address, whatever the format of this mail article. This linear image sensor is typically an integrated module having adjacent CCD or CMOS semiconductor detection cells, a collimating optics, and a lighting system that when activated illuminates the surface on which the sensor is positioned. and delivers back to each of the sensor cells a signal proportional to the light reflected from the surface of the mailpiece.

The operation of the feeding device will now be described with reference to FIGS. 5A to 5C which show the moving optical reading unit in three successive advancement positions of a mail article (the visual effects are deliberately exaggerated to facilitate comprehension). On the Figure 5A , the mobile set of optical reading 26 is at rest, the sensor then passing through the transport path of the mail items (note that this crossing can be advantageously limited by the addition of a stop). On the Figure 5B , the mail item advanced in this transport path, came into contact with the leading edge of the upstream baffle that it raised slightly to take the illustrated position. On the Figure 5C the mail piece has further moved downstream and has engaged the front transport rollers 22A, 22B. During the entire movement of the mailpiece, the sensor 20A has been constantly in contact with it, which has enabled it to acquire line by line an image of the surface of the mail item. This acquisition is performed from a start signal delivered by the detector of the front of the mail article or by an automatic recognition and under the control of the processing means 28.

The signals collected by this processing means may be analog or digital depending on the nature of the sensor and will therefore be digitized and standardized if necessary at a programmable circuit (for example an FPGA) before being stored in a data RAM. the module at which the image of the mail item will be reconstructed. A digital processing of this image at the level of a microprocessor of the module will then, depending on the application implemented and available in a program ROM, an interpretation of this image, that is to say an OCR recognition by example of the recipient address and, when present on the mail item, a barcode recognition. The recognition of these address or code data printed on the mail items will, as is known, from these data and possibly postal data entered. by the operator, the creation of a database of addresses and tracking of mail items.

The figure 6 illustrates a second embodiment of the mobile optical reading assembly 26 in which a device for applying to the sensor a force in a direction perpendicular to the direction of travel of the mail article, is added to both promote the sensor support on the mail item and also to ensure that the sensor returns quickly enough to the scanning position when passing mail items at a high rate. Without this device, the sensor could, when passing a mail item, be projected upward, and not have enough time to return to position before the passage of the next mail article. More particularly, such a device is formed by a damping device 60 or any other similar system responsible for pressing the upper face of the support.

In addition, the sensor and its movable support may advantageously be coupled to a pressing member 62 arranged at the sensor's right under the transport path of the mailpieces and which pushes the mailpiece at its lower face, in order to flatten its upper part against the sensor. This pressing member makes it possible to ensure that the article of mail will be in contact uniformly at the level of the sensor, thus avoiding the formation of waves on the surface of the mailpiece. It can be mounted on springs or any other similar system to apply pressure on the mail piece.

In this case, the damping system mounted on the sensor and the springs located on the presser, allow to apply pressure on both sides of the mail piece. Careful adjustment is necessary in order to find a preferential position that allows for optimal quality scanning. Too much pressure low will not sufficiently squeeze the mail item and the quality of the scan will be degraded. Pressures too strong will cause a slowing of the mail item, or even its blocking, and thus a scan that will also be of poor quality.

In practice, the inventor has found that the scanning is optimal for a force of the pressing member equal to twice the force applied on the support by the damping system.

It may be noted that, applied to the embodiment of the Figure 5A , the pressure member can also provide the aforementioned abutment function of the sensor in its rest position.

The figure 7 illustrates in perspective and in section another exemplary embodiment of the mobile optical reading assembly 26. There is found its CIS sensor 20A mounted in the bridge-shaped support with its upper wall 42 and its two longitudinal walls 32, 34, to the base of which are arranged the upstream deflectors 32A and downstream 34A. In this embodiment, the fixing and pivoting of the support are provided by a ball joint 64 fixed to the end of a single suspension arm 44, so as to allow in addition to the vertical displacement along the Z axis, the rotations about the X and Y axes. The rotation about the Z axis is prohibited by two stops 66 disposed at both ends of the longitudinal wall 34 and intended to come into contact with a structural part of the machine. Of course, this configuration with a ball joint can also be implemented with the two suspension arms 44A, 44B (the two ball joints (one per arm) then advantageously replacing the existing clearance at the attachment of these two arms with the frame) .

It will be noted that, if in the embodiments described, the mobile optical reading assembly is mounted in an independent module, it is of course obvious, that because of its particular compactness, it can be arranged in each of the modules of the franking system, that is to say both in its module 14 for selecting mail items, and in its module 16 for weighing mail items, in its module 18 for printing these mail items or in a folding and insertion module when it exists.

Claims (10)

Digitizer device (26) for postage meter postage system, comprising: . a contact image sensor (CIS 20A), . a support (30) to which said sensor is attached, said support being arranged in a direction perpendicular to the advancement of the mailpieces in said franking system and having a longitudinal axis Y and a transverse axis X, and . movable securing means (44A, 44B) for securing said support to a structural portion of said franking system so as to allow vertical movement of said support (translation about the Z axis) and pivoting thereof both about said longitudinal axis (rotation about the Y axis) and about said transverse axis (rotation about the X axis). Digitizing device according to claim 1, characterized in that said movable fixing means comprises two suspension arms (44A, 44B) articulated at one end on a common axis (54) integral with said structural part and at another end on a pivot axis (46A, 46B) fixed to said support, said pivoting about said transverse axis (rotation about the X axis) being provided by a set of connecting said first end. Digitizing device according to claim 1, characterized in that said movable fixing means comprises a suspension arm (44) articulated at one end on a common axis (54) integral with said structural part and at another end on a ball joint (64) secured to said support, so as to allow, through said ball joint, said pivoting both around said transverse axis (rotation about the X axis) and about said longitudinal axis (rotation about the Y axis), and in that stops (66) are further provided to prevent rotation during said vertical movement of said support. Digitizing device according to claims 1 to 3, characterized in that it further comprises a damping device (60) for damping said vertical displacement of said support. Digitizing device according to claim 4, characterized in that said damping device is constituted by a single spring. Digitizer according to claims 1 to 5, characterized in that said contact image sensor is formed of an integrated module comprising adjacent semiconductor detection cells, a collimation optics and a lighting system. Digitizer according to one of Claims 1 to 6, characterized in that it is mounted in an independent subassembly of the franking system. Digitizer according to one of Claims 1 to 6, characterized in that it is mounted in one of the following subassemblies of the franking system: feeder, postal scale, franking machine, folder / inserter. A postage meter element having a digitizer as claimed in any one of claims 1 to 8, wherein said mail items are applied against said digitizer by a presser member (62) disposed at the right of said scanner device. scanning. Element of a franking system according to claim 9, characterized in that said pressure member is mounted on springs or any other similar system for applying a pressure on the mail piece.

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