Patent Application
20090177312
The present invention relates exclusively to the field of processing post and it more particularly concerns a postage meter system of which one of the constituent modules, such as the module for feeding postal articles (feeder), the module for weighing postal articles (postal scales), the module for printing these postal articles (postage meter in the strict sense), the module for folding and inserting (folder/inserter) or any other independent module, comprises an integrated image sensor.
It is well known that postal administrations or private carriers use complex digitization systems enabling many checking and tracking applications, in particular the analysis of postal articles and their sorting according to their destination. These systems are, however, particularly expensive and their volume is large due in particular to the use of cameras. They are therefore only really of interest to a sender if this sender processes large volumes of post, such as a router. Indeed, in the context of a standard postage meter system in the post-dispatch room of a company and formed for example of a feeder, postal scales, a postage meter and optionally a folder/inserter, the digitization of postal articles using similar technologies is not conceivable.
For these conventional postage meters it is necessary to make use of small-sized sensors, of the CIS (Contact Image Sensor) type, today used above all in the digitization units of photocopiers. However, in these photocopiers, as the thickness of the paper is relatively constant, low and uniform, the sensor known as a CIS is generally stationary.
It is completely different with a postage meter system. This is because the upper face of postal articles is not always planar, variations in thickness due to the content of the article or misshapen articles due to being transported through the system may alter the quality of the digitization. In addition, the digitized area is relatively large, typically greater than 30 cm. This is because, depending on the format of the postal article, the position of the destination address is different and it is desirable to be able to digitize not only this destination address but also the other information visible on the postal article (amount of postage paid, address of the sender, etc.).
A first solution to these problems is given by the digitization device specially adapted to postage meter systems and illustrated in patent application FR 07 57285 filed in the name of the applicant. In this movable and no longer stationary device, the transporting of postal articles takes place while keeping a common reference which is the lower face of these postal articles. Thus, whatever the thickness of the postal article, its lower face will therefore always pass at the same place in the system.
This device yields overall satisfaction, especially for low or medium postage metering rates. Conversely, for high rates it suffers from certain drawbacks owing mainly to the amplitude of sensor movement, which may then be a few tens of mm. Indeed, this sensor has to move vertically by a value equal to the thickness of the postal article (which may vary from 0.2 mm to more than 20 mm). Yet, if the rates of postage metering and hence of digitization are high—they may be as much as 5 articles per second—rapid vertical movement of the sensor causes vibrations which, apart from the fact that they are unfavorable for good digitization quality, may damage it. In addition, at high speed, during the passage of a postal article of significant thickness (more than 15 mm) followed by one of lesser thickness (a few mm), the sensor does not have time to return to its rest position in order to digitize the second postal article.
The object of the present invention is therefore to eliminate the aforementioned drawbacks by installing a sensor, called a CIS, in a postage meter system that enables correct digitization of the entire surface of postal articles, whatever the format (from business card format through to the largest format) and the thickness of this postal article. One aim of the invention is to allow this sensor to adapt itself to the movements and to misshapen surfaces of the postal article, while enabling a digitization of sufficient quality to be able to use character recognition software analyzing the digitized images. Another aim of the invention is to control the distance between the sensor and the postal article as a guarantee of good digitization quality. Another aim of the invention is also to propose a feeder device that does not require a redefinition of its general architecture.
These aims are achieved by a digitization device for a postage meter system for postal articles, comprising:
Thus, through this simple structure the sensor is able to move both vertically and rotationally about its longitudinal and transverse axes, which enables it to adapt to all thicknesses of postal article and to digitize automatically postal articles during their movement.
According to a preferred embodiment, said movable fixing means comprises two suspension arms hinge-joined at one end to a common axle joined to said part of the structure and at another end to a swivel pin fixed to said support, said swiveling about said transverse axis being ensured by a play in the connection of said first end.
According to another embodiment, said movable fixing means comprises a suspension arm hinge-joined at one end to a common axle joined to said part of the structure and at another end to a ball joint joined to said support so as to enable, by means of said ball joint, said swiveling both about said transverse axis and about said longitudinal axis, stops furthermore being provided in order to avoid any rotation during said vertical movement of said support.
Preferably, it furthermore comprises a damping device in order to damp said vertical movement of said support. Said damping device may consist of a simple spring.
Said contact image sensor is formed of an integrated module comprising adjacent detection cells made of semiconductor, collimation optics and an illumination system.
Depending on the available space, the digitization device may be mounted in an independent subassembly of the postage meter system or in one of the following subassemblies of the postage meter system: feeder, postal scales, postage meter, folder/inserter.
The invention also relates to any element of a postage meter system comprising such a digitization device and in which said postal articles are applied to said digitization device by a presser unit positioned to the right of said digitization system. Said presser unit is preferably mounted on springs or any other similar system enabling the application of a compressive force to the postal article.
The invention will be understood better in view of the following detailed description, accompanied by illustrative and nonlimiting examples with regard to the following figures, in which:
The invention is based on the use of a system described as a high reference system, in which the upper face of the postal article, i.e. the face that it is desired to digitize, is always situated in the same position, whatever the thickness of this postal article and therefore always passes at the same place in the system.
In such a system, the sensor, called a CIS, is fixed on a movable support which follows the deformations and movements of the upper face of the postal article. The sensor is thus not located in a fixed position because, as the transporting of postal articles in the machine is not perfect, the upper face of these postal articles is not always strictly planar. It is therefore necessary to allow the sensor to move and to swivel while keeping a small fixed distance between the sensor and the upper face of the postal article that it is desired to digitize, as the depth of field of such a sensor is limited.
In the embodiment illustrated, the postage meter system furthermore comprises an independent optical reader module 20 comprising a sensor 20A, advantageously linear, of the so-called “contact” type, positioned upstream of the dynamic weighing module (though a different arrangement is also conceivable), in order to acquire a digital image of the postal article 10 and to extract from this at least the identifier 10B relating to the value-added service desired for this postal article and the destination address 10A carried on the postal article. To do this, this image sensor is associated with barcode recognition and optical character recognition (OCR) software. The printing module furthermore comprises an improved user interface 18A with a keyboard enabling the display on a screen 18B of all or part of the image of the postal article thus digitized and, if necessary, correction of the postal data extracted from this image. The keyboard may be a physical keyboard interacting with a virtual keyboard on the screen 18B, which is then advantageously of the touch type, or purely and simply be replaced by this touchscreen. The printing module may also comprise storage means (not shown) of the database type in order to store the image of the envelope thus digitized.
According to the invention, in order to enable automatic processing of postal articles and not to increase the size of the module, it is proposed to put a movable optical reader assembly 26 between these two series of transport rollers, said assembly comprising the sensor 20A and enabling, in connection with a processing means 28, digitization and automatic recognition of the information carried by these postal articles. This assembly will be movable to follow the upper surface of the postal article, which is not uniform, and therefore ensure through its movement and its privileged position in the system an optimum digitization quality, whatever the thickness of the postal articles, in particular in the presence of thick envelopes. The triggering of digitization and the processing of data by the processing means 28 may advantageously be synchronized using a detector (not shown) of the front of each of the postal articles. This digitization may also be carried out continuously, the synchronization then being carried out by detecting change in the gray level or change in the color appearing systematically when passing from one envelope to another.
The perspective of
Of course, the movable support may be connected to the frame of the module by any other mechanical connection than the two previously described suspension arms provided that a degree of freedom for vertical movement is allowed. Thus, a device simply comprising two springs (or two damping devices) suspended from the frame and retaining the upper wall of the support are also perfectly suitable.
The sensor is advantageously a contact image sensor, linear in type, the length of which is designed for digitizing at least one width of a postal article covering the postmark and the destination address, whatever the format of this postal article. This linear image sensor is typically an integrated module comprising adjacent CCD or CMOS detection cells made of semiconductor, collimation optics and an illumination system which, when it is activated, illuminates the surface over which the sensor is positioned and delivers in return, at each of the detection cells, a signal proportional to the light reflected by the surface of the postal article.
The operation of the feeder device will now be described with regard to
The signals gathered by this processing means may be analog or digital depending on the nature of the sensor and will therefore, if necessary, be digitized and normalized at a programmable circuit (for example, an FPGA) before being stored in a RAM data memory of the module in which the image of the postal article will be reconstituted. Digital processing of this image in a microprocessor of the module will then, depending on the application employed and available in a ROM program memory, enable an interpretation of this image, i.e. optical character recognition (OCR), for example, of the destination address and, when they are present on the postal article, barcode recognition. The recognition of these address or code data printed on the postal articles will allow, as is known, the creation of an address and postal article tracking database from these data and optionally from postal data input by the operator.
In addition, the sensor and its movable support may advantageously be coupled to a presser unit 62 positioned to the right of the sensor in the transport path of the postal articles and which presses on the lower face of the postal article in order to flatten its upper part against the sensor. This presser unit makes it possible to ensure that the postal article is uniformly in good contact with the sensor, thus avoiding the formation of waves on the surface of the postal article. It may be mounted on springs or any other similar system enabling the application of a compressive force to the postal article.
In this case, the damping system mounted on the sensor and springs situated on the presser enable the application of a compressive force on both sides of the postal article. Fine adjustment is necessary so as to find a preferred position that allows a digitization of optimum quality to be obtained. Compressive forces that are too low will not allow the postal article to be pressed enough and the digitization quality will be reduced. Compressive forces that are too high will cause the postal article to slow down, or even its blockage, and therefore digitization which will also be of poor quality.
In practice the inventor has been able to observe that the digitization is optimum for a force by the presser unit equal to or double the force applied to the support by the damping system.
It may be noted that, applied to the embodiment of
It will have been noted that although the movable optical reader assembly is mounted in an independent module in the exemplary embodiments described, it is of course obvious that, due to its particular compactness, it may be positioned in each of the modules of the postage meter system, i.e. just as well in its module 14 for selecting postal articles as in its module 16 for weighing postal articles, in its module 18 for printing these postal articles, or again in a folding and inserting module when it exists.
| Number | Date | Country | Kind |
|---|---|---|---|
| 0850043 | Jan 2008 | FR | national |
