FR2919522A1 - Flexible band e.g. web paper, printing device for self-service printing terminal, has displacement unit formed by tensioning unit for allowing band to be stressed from initial position to final position in permanent manner - Google Patents

Abstract

The device has a displacement unit for displacing a band (1) between an initial position (PI) and a final position, and acting on an end (8) or near the band located in downstream of printing support surfaces (3) in a movement direction of the band. A cutting unit cuts the band into sheets after a printing phase. The displacement unit is formed by a spring type tensioning unit (6) for allowing the band to be stressed from the initial position to the final position in a permanent manner by exerting gravitational, elastic, or magnetic forces. An independent claim is also included for a method for printing a flexible band stored in a roller.

Description

The present invention relates generally to the printing of tapes

flexible in a printable material.

  The invention more particularly relates to a device for printing a flexible strip of a printable material, such as paper, stored in roll, intended to be cut into sheet after printing, comprising controlled unwinding means of the strip, a circulation path of the unrolled portion materialized by at least one bearing surface capable of forming at least a portion of a plane called a printing support plane, at least one printing member, such as a head of inkjet printing, arranged along the circulation path, means for moving the strip, between an initial position and a final position, acting on, or in the vicinity of, the end of the strip located downstream of the or bearing surfaces taken in the direction of circulation of said strip, and means for cutting the strip 15 after the printing phase.

  The invention also relates to a printing terminal of the type comprising such a printing device and a printing method.

  Today, self-service print terminals commonly use "sheet-by-sheet" inkjet or laser printers, which are modified to accommodate the use of the print terminals. These printing devices that use a "sheet-fed" system require repeated interventions by the operator who must reload the printing device when there is no more paper. In addition, the use of reams of paper is expensive in handling time and generates a large volume of packaging. In addition, with such "sheet-by-sheet" printing devices, problems of paper jam are observed.

  Also known from EP0669538 is a device for printing a tape stored in a roll intended to be cut into sheets. This printing device comprises means for moving the strip formed by a motorized gripper to pull the strip in one direction, and winding means in the opposite direction, so as to obtain an alternating displacement of the strip to achieve several print passes. Such a device requires a complex motorization since it is necessary to provide a motor controlling the movement of the clamp and a motor controlling the rewinding of the band. Above all, the controls of these two motors must be very precise so as not to cause a tearing of the band. These two motors which exert tensile forces on the web in both directions also need to be precisely synchronized with each other to avoid wrinkling of the web or paper jam.

  Printing devices are also known which comprise motorized unwinding means for the strip and displacement means, or in advance, formed by pressure rollers which exert a tensile force on the strip by crushing the strip. against a support plane and simultaneous rotation of the roller. However, with such printing devices, synchronization problems are observed between the motor which controls the unwinding of the belt and the motor which controls the rotation of the pressure roller. This results in problems of creasing or tearing of the strip. The risk of paper jams is important. In addition, the motorization used is often complex.

  A first object of the invention is to reduce the risk of paper jam.

  Another object of the invention is to simplify the motorization of the printing device.

  Another object of the present invention is to limit the number of interventions by the operator. To this end, the invention relates to a device for printing a flexible strip of a printable material, such as paper, stored in roll, intended to be cut into sheet after printing, comprising: - controlled unwinding means of the strip, a circulation path of the unrolled portion materialized by at least one bearing surface capable of forming at least a portion of a plane called a printing support plane, at least one printing member, such as an ink-jet printing head, arranged along the circulation path; means for moving the strip, between an initial position and a final position, acting on or near the end of strip located downstream of the bearing surface or surfaces taken in the direction of flow of said strip, and - cutting means of the strip after the printing phase, characterized in that the displacement means are formed by voltage means which, of said p initial osition to said final position, permanently stress said band, by exercise of gravitational forces, or elastic, or magnetic. With such a design of the printing device, the flatness of the band is ensured during printing passes made by the printheads. Indeed, the unwinding means release the desired strip length to be printed and the tensioning means tension the released strip length. These tensioning means according to the invention thus ensure reliable printing of the unrolled portion of the strip.

  The tension being obtained by the exercise of gravitational, or elastic, or magnetic forces, that is to say so-called conservative forces, the tensioning means follow "naturally" the unwinding of the strip. It is therefore not necessary to provide means for synchronizing the displacement of the tensioning means relative to the unwinding means of the paper web. Indeed, it is the unwinding of the paper web which allows the displacement of the tensile means under the effect of gravitational, or elastic, or magnetic forces. In addition, such a device makes it possible to obtain a specific format for printing, such as an A4 format, to use a roll of paper or roll instead of a paper feed of leaf". The maintenance and printing costs are thus reduced. Similarly, the use of a strip of paper stored in the form of a roll instead of reams of paper sheet, allows to generate much less packaging.

  The motorization of such a printing device is also simplified since the tensioning means do not use a motor to stretch the band. This avoids any problem of synchronization of the drives of the voltage means and the unwinding means to ensure the displacement and tension of the band. The risk of jamming or creasing of the papermill is then very limited.

  According to an advantageous characteristic of the invention, the printing device 15 comprises motorized return control means of the displacement means in the initial position, said motorized control means being inactive during the displacement of the displacement means from the initial position to the final position.

  According to an advantageous characteristic of the invention, the tensioning means comprise means for gripping said end of the strip situated downstream of the bearing surface or surfaces taken in the direction of circulation of said strip, said gripping means being controlled in displacement between a setting position of the downstream end of the strip and a release position of the strip by means of the motorized return control means of the displacement means in the initial position.

  According to an advantageous characteristic of the invention, the cutting means are controlled in operation by means of said motorized means 30 for controlling the return of the motorized means of displacement in the initial position. According to an advantageous characteristic of the invention, the tensioning means carry the gripping means and the cutting means. According to an advantageous characteristic of the invention, the tensioning means form means for weighting the band.

  When the unwinding means release a given length of strip, the tensioning means are "naturally" displaced by their own weight so as to tension the unrolled portion of the strip. The unrolled portion of the strip once tensioned then also plays a role of retaining the tension means, until these tensioning means come into abutment in their final position.

  According to an advantageous characteristic of the invention, the tensioning means comprise a pivoting main structure mounted between the initial position and the final position, freely pivotable about an axis substantially orthogonal to the unwinding direction of the strip, said main structure being returned to the initial position by said motorized control means.

  According to an advantageous characteristic of the invention, the tensioning means 20 comprise a mobile secondary structure mounted movably relative to the main pivoting structure to be brought closer to or away from said pivoting main structure so as to form the gripping and cutting means. Of the band.

  According to an advantageous characteristic of the invention, said motorized control means are formed of a rotary cam driven in rotation by a motor, said cam having a profile designed to activate or deactivate the gripping means, and being provided with a finger adapted to abut against an element secured to the displacement means in order to move the displacement means from said final position to said initial position.

  According to an advantageous characteristic of the invention, the device comprises means, such as an electromagnet, temporarily retaining the displacement means in the initial position.

  According to an advantageous characteristic of the invention, the device comprises a rolling means, such as a wheel, wheel, or roller, counter-rotating with respect to said pivoting principal structure of the displacement means, so as to avoid driving the band by said pivoting main structure, during the return of the displacement means in the initial position. The invention further relates to a printing terminal of the type comprising a printing device as described above.

  The invention also relates to a method for printing a flexible strip of a printable material, such as paper, stored in a roll, comprising: - a step of gripping the downstream end of the strip taken in the direction of 15 circulation of said strip, - a step of unwinding a predetermined length of the strip, and - parallel to the unfolding of the strip, a step of moving and printing the unrolled portion of the strip, between an initial position and a final position, this moving and printing step being followed by a step of cutting the sheet web, characterized in that, for moving the web from said initial position to said final position, said strip in tension permanently by the exercise of gravitational forces, or elastic, or magnetic.

  According to an advantageous characteristic of the printing method according to the invention, between the printing step and the cutting step, there is provided an additional step of returning the displacement means to the initial position.

  The invention will be better understood on reading the following description of exemplary embodiments, with reference to the appended drawings in which: FIG. 1 is a schematic side view of the printing device according to the invention, in a state waiting for the triggering of a print phase, the moving means of the strip being in the initial position; FIG. 2 is a view of the printing device of FIG. 1, during a printing phase of the strip; - Figure 3 is a view of the printing device of Figure 2, at the end of printing, the belt moving means being in the final position. FIG. 4 is a view of the printing device of FIG. 3, after printing and during the ascent of the means for moving the strip in initial position; - Figure 5 is a view of the printing device of Figure 4, after cutting the sheet web; FIG. 6 is a schematic side view of the displacement means according to the invention, the gripping means of which are in the gripping position of the strip; - Figure 7 a view of the displacement means of Figure 6, the gripping means being in the release position of the strip; FIG. 8 is a diagrammatic sectional view of the gripping means and means for cutting the strip according to the invention, before cutting the strip; - Figure 9 is a view of the gripping means and the cutting means of Figure 8, during the cutting of the strip; FIG. 10 is a view of the gripping means and the cutting means of FIG. 9, in the state of release of the cut strip portion; FIG. 11 is a view of the gripping means and the cutting means of FIG. 10, the gripping means being in the gripping position of the strip; - Figure 12 is a schematic side view of a cam controlling the activation and deactivation of the input means according to the invention. FIG. 1 shows a device for printing a flexible web 1 of a printable material stored in a roll (not shown), to be cut into sheets after printing. In the example detailed in FIGS. 1 to 5, the strip 1 is a strip 1, or strip, of paper. Preferably, the printing device is intended to be housed in the enclosure of a self-service printing terminal. This printing device comprises controlled unwinding means 2 of the strip 1. The unwinding means of the strip comprise at least conventionally a roller 17 supporting the strip, driven in rotation by a motor 13, and a roller 36 bearing, pressed against the support roller 17 and the band 1 by return means 37, such as a spring.

  There is also provided a circulation path 3 of the unrolled portion materialized by at least one bearing surface 3 which forms a plane 3 support printing. The print medium plane 3 comprises at its downstream end a return roll 38.

  In the example illustrated in Figures 1 to 5, there is provided one or more printing members 5, here inkjet printing heads, which are arranged along the circulation path 3. Alternatively, consider using other printing devices. The printing device also comprises means for moving the strip 6 between an initial position PI and a final position PF. These displacement means 6 act on or near the end 8 of the strip located downstream of the bearing surface 3 taken in the direction of flow of said strip 1. The initial position PI corresponds substantially to the position moving means at the beginning of the printing phase, and the final position PF substantially corresponds to the position of said moving means at the end of the printing phase.

  Cutting means 10 are also provided for the web 1 after the printing phase (see FIGS. 8 to 11). These cutting means 10 are described in more detail below.

  Characteristically according to the invention, the displacement means 6 are formed by tensioning means 6, generally of ballast, spring or magnet type, which, from said initial position PI to said final position PF, permanently solicit tension said band 1, by exercise of gravitational forces, or elastic, or magnetic. Preferably, and as illustrated in FIGS. 1 to 5, the forces exerted are of the gravity type, the tensioning means 6 being formed by weighting means.

  As detailed below, motorized control means 4 are provided for returning the displacement means 6 to the initial position PI. These motorized control means 4 are inactive during the displacement of the displacement means 6 from the initial position PI to the final position PF.

  The tensioning means 6 also comprise gripping means 7 of said tape end 8 which are controlled in displacement between a gripping position PF 'of the downstream end of the strip (FIG. 6) and a release position PL of the band 1 (FIG. 7) by means of the motorized control means 4. The cutting means 10 are also controlled in operation by means of said motorized control means 4. The tensioning means 6 carry the means of seizure 7 and the cutting means 10.

  As mentioned above, in the example shown in FIGS. 1 to 5, the tensioning means (3 form weighting means 6 of the band 1.

  The tensioning means 6 comprise a pivoting main structure 11 mounted between the initial position P1 and the final position PF, pivoting freely about an axis A11 substantially orthogonal to the unwinding direction of the strip 1. The weighting means are thus mainly formed by the main pivoting structure 11. The gripping means 7 and cutting 10 also participate, because of their weight, the ballasting of the strip.

  As shown in FIGS. 1 to 11, the tensioning means 6 comprise a movable secondary structure 12 mounted movably relative to the main pivoting structure 11 to be brought closer to or away from said main structure 11 so as to form the gripping means 7. and cutting 10 of the strip 1. The gripping means 7 are thus in the form of a gripper The movable secondary structure 12 is mounted to rotate with the pivoting main structure 11 about the axis of rotation A11. In addition, the mobile secondary structure 12 is mounted free translationally relative to the main pivoting structure 11, in a direction radial to the axis of rotation A11. In particular, as illustrated in FIGS. 6 and 7, the movable secondary structure 12 is slidably mounted in the main pivoting structure 11. Thus, when the main structure 11 rotates about the axis of rotation A11, it rotates the mobile secondary structure 12 which, independently of the pivoting of the main structure 11, is free to slide relative to said main structure 11.

  The lower end of the mobile secondary structure 12 carries casters 40 which rest on cams 15 integral with the axis of rotation A11 which also constitutes the free pivot axis of the main pivoting structure 11. As illustrated in Figures 8 to 11, there is also provided means, for example one or more springs, return 29 of the upper part of the clamp 7 in the closed position, that is to say in support against the part 20 of the forceps.

  The motorized control means 4 are formed by the rotating cams rotated by a motor 26. Each cam 15 has a profile 16 (see FIG. 12) designed to activate or deactivate the gripper 7. For this purpose, the profile 25 of FIG. each cam 15 is made in the following manner. The profile of the cam has a first angular portion P1 P2 which corresponds to the angular sector that traverses the pivoting main structure 11 when it pivots from the initial position PI to the end position PF. Along this first angular portion, the radius of the profile of the cam relative to the center of rotation is constant. The first angular portion P1 P2 is followed by a second angular portion P2P3. Along this second angular portion, the radius of the profile increases from P2 to P3. Each cam 15 also comprises a finger 18 designed to abut on an abutment member 19 integral with the main pivoting structure i0 and to enable said pivoting main structure to be raised. The operation of this cam, in relation to the gripping and cutting means and the main pivoting structure, is described in detail below. As illustrated in FIGS. 1 to 5, there is also provided a sensor 30 making it possible to measure the angular position of the pivoting principal structure 11 and a sensor 31 making it possible to measure the angular position of the cams 15. The printing device comprises means for example an electromagnet or a rotating cam system with a hook, temporarily holding the moving means 6 in the initial position P1. These retaining means 20 can be activated between the printing phases and can be deactivated during the printing phases.

  The gripping means 7 comprise clamping means of the band 1 arranged to clamp the band 1 into two distinct parts. As illustrated in Figures 8 to 11, the clamping means are formed of a pair of tampons 34, 35 deformable, said downstream because downstream of the cutting means of the strip, and a pair of tampons 24, 25 deformable , said upstream because upstream of the cutting means of the strip. Each pair of deformable buffers comprises an upper deformable pad 25 and a lower deformable pad 24, 34. The deformable buffers are preferably of elastomeric material.

  The cutting means 10 comprise a cutting blade 10A and a counterblade 10B disposed between the clamping means. The blade 10A is integral with the secondary mobile structure 12 and the counterblade 10B is integral with the main pivoting structure 11. The cutting blade extends in a plane orthogonal to the plane of the band portion clamped between the pairs of clamping means. As shown in FIGS. 8-11, the upper part of the main structure 11 which forms the jaw lower part of the clamp 7 comprises the pads 24, 34 deformable lower and, between these two pads, against the blade 10B. The upper part of the movable secondary structure 12 which forms the upper jaw of the clamp 7 comprises the two upper deformable buffers 25 and 35, and between these two buffers, the blade 10A. There is also provided a control unit (not shown) control means and print heads. The printing method implemented from such a printing device is described below.

  As shown in FIG. 1, before the triggering of a printing phase, the clamp 7 and the pivoting main structure 11 are held in the initial position PI by the electromagnet which is activated.

  The clamp 7, which is closed, clamps the downstream end 8 of the strip 1 taken in the direction of flow of said strip. Specifically, the end 8 of the band 20 is clamped between the upper and lower deformable pads 25 of the pair of deformable pads (see FIG. 11).

  When a print phase is triggered and as shown in Figure 2, the retaining means 20 are disabled. The main pivoting structure 11 is then left free, subjected to its own weight, and simply retained by the band clamped by the clamp 7. The unwinding means 2 constrain the band 1 moving. The movement of the main pivoting structure 11 is thus directly induced by the action of unwinding means 2 which control the unwinding of the strip. The motor 13 then drives the support roll 17 in rotation so as to unroll a portion 9 of the band.

  The pivoting structure 11 continuously follows the movement of the downstream end 8 of the strip resulting from unwinding of the strip 1, while being held in its fall by said strip 1 and the gripping means 7, until the structure 11 reaches said final position PF formed by the stop 27 (see Figures 2 and 3). Because the structure 11 accompanies the unwinding of the strip while being retained in its fall by the strip and the gripping means, the unrolled portion of the strip is displaced by the pivoting structure 11 while being tensioned continuously, which ensures the flatness of the band at the level of the plane 3 print media. As the displacement of the pivoting main structure is thus controlled by the unwinding of the strip, the tensioning means and the unwinding means are naturally synchronized.

  Parallel to the unwinding of the band 1 and the displacement of the unrolled portion 9 of the band 1 between the initial position PI and the final position PF, the portion 9 unwound is printed. To do this, the printing members are moved over the width of the unrolled portion 9 of the strip.

  When the main pivoting structure 11 is moved, by free pivoting, from the initial position to the final position, the more the main structure 11 pivots away from its initial position (a substantially vertical position), the greater the tension exerted on the band increases. Indeed, the more the main structure 11 pivots downwards, the less the effort due to its weight is taken up by the axis of rotation. Thus, such a free pivoting assembly of the main structure 11, forming ballast means, ensures a sufficient tension of the strip as it is unwound.

  As recalled above, the motorized control means 4 are inactive during the displacement of the displacement means 6 from the initial position PI to the final position PF. In particular, the cams 15 are not actuated in rotation and the rollers 40 of the mobile secondary structure 12 are moved, by the pivoting of the main pivoting structure 11, along the cam portion P1 P2 of constant radius with respect to the axis of rotation. The radius of this first cam portion ensures that the clamp 7 remains closed during the fall of the pivoting main structure 11 to the stop 27.

  In final position PF, the rollers 40 of the clamp 7 are located at the end of the first angular portion P1, P2 of constant height.

  As shown in FIGS. 3, 4 and 12, when the pivoting main structure 11 reaches its end position in abutment, the motorized rotary cams are actuated in rotation by the motor 26. each cam rotates from the corner sector P2P3 which causes the opening of the clamp 7, as the profile radius of the cam 15 increases to point P3. The cam 15 thus opens the clamp 7 by spacing the upper part of the mobile secondary structure 12 relative to the upper main structure 11 pivoting.

  When each of the rollers 40 reaches the end of the P2P3 portion, ie at the point P3, the clamp is fully open. The finger 18 of each cam 15 abuts against the corresponding abutment member 19 integral with the main structure 11 pivoting.

  As shown in FIG. 4, the continued rotation of each cam causes the pivoting main structure 11 of said final position PF to be raised to said initial position P1, while keeping the clamp 7 fully open, since each wheel 40 is in position. pressing the associated cam at the level of the highest point P3 of the portion P2P3.

  As represented in FIGS. 1 to 5 and 8 to 11, the pivoting main structure 11 is equipped with a rolling means 23, here a roller, counter-rotating with respect to said pivoting principal structure 11 of the displacement means 6, so as to avoid the driving of the band 1 by said pivoting main structure 11 during the return of the locating means 6 to the initial position PI. The use of such a roller 23 makes it possible to avoid any problem of jamming of the band 1 in the clamp 7 during the ascent to the initial position P1 of the main pivoting structure 11. Indeed, this roller 23 allows by its counter-rotating rotation with respect to the direction of pivoting of the main pivoting structure 11, to drive the strip downstream of the displacement means, taken in the direction of circulation of said strip, during the ascent of said displacement means 6. In the example illustrated in Figures 1 to 5 and 8 to 11, the roller 23 is located on the side of the clamp 7 opposite the unwinding means 2. The roller 23 is rotated by the pivoting of the main structure 11 pivoting using a system of bevel gear, bevel gears and a belt. Alternatively one can predict that the roller 23 is motorized.

  As shown in FIGS. 5 and 8 to 10, once the gripper 7 and the main pivoting structure 11 have been raised to the high position, or initial position PI, the sheet cutting step of the strip is carried out.

  The activated retaining means 20 retain the main pivoting structure 11 in a vertical position, so that it is possible to cut the strip by closing the clip 7. In fact, the rotation of the cam in the direction of closing the clamp from P3 to P2 no longer allows the pivoting main structure 11 to be driven uphill, and the electromagnet then retains the main pivoting structure 11 in the initial position to prevent it from falling back under the effect of its own weight. In other words, the electromagnet makes it possible to actuate the clamp by rotating the cam, without the pivoting main structure 11 falling back.

  When closing the clamp, that is to say as each wheel 40 is moved on the profile of the corresponding cam 15, from the point P3 to the point P2, the deformable pads 24, 25, 34, 35 each of the two pairs of pads are brought together to clamp the web at the beginning of the print area. By closing the clamp (see Figure 8), the deformable pads are pressed against each other, thus firmly holding the printed portion 9 of the strip to be cut. Then, the jaws of the clamp, continuing to approach one another under the effect of the deformations of the pads, the cutting blade 10A cuts the band (see Figure 9). The clamping of the band by the deformable pads 24, 25, 34, 35, on either side of the cutting zone, makes it possible to obtain good cutting conditions. Thus, the complete closure of the clamp causes the cutting of the band. As illustrated in FIG. 10, the two pairs of deformable buffers 24, 25, 34, 35 are then loosened so as to leave the cut sheet corresponding to the printed portion 9 of the strip free. The cut sheet falls and then slides under the effect of its weight along a guide wall 39. As illustrated in FIG. 11, the clamp is then closed by rotation of the cam from P3 to P2 to grip the new end 8 of the band between the deformable buffers 24, 25 upstream, so as to be operative when triggering. a new printing phase. The printing device 15 then returns to the configuration shown in Figure 1, waiting for the triggering of a new printing phase.

  Finally, when the series of prints is finished, a flap 32 opens and the series of printed sheets slide by gravity into a collection tray 33 accessible to the user.

  As recalled at the beginning of the description, such a printing device is preferentially integrated in a self-service printing terminal, which makes it possible to obtain a terminal operating reliably and offering high quality prints.

  The present invention is not limited to the embodiment described and shown, but the art can apply any variant within his mind. In the example illustrated in Figures 1 to 5, the tensioning means are ballast type. As a variant, provision may be made for the tensioning means 6 to be formed instead of the weighting means by elastic return means 5 of the strip, such as a spring, or by any other device capable of ensuring the traction of the strip. , such as a means for exerting a magnetic type force. One can then provide to use a magnet associated with means for gripping the strip and another magnet disposed at the final stop position.

  In addition, in the example illustrated in Figures 1 to 5, the strip is cut into sheets after printing. Of course, the device and the printing method described above are applicable to any format. For example, it is possible to print larger (or smaller) formats by increasing (respectively decreasing) the angular travel of the main pivoting structure.

Claims (13)

  A device for printing a flexible web (1) of a printable material, such as paper, stored in a roll, to be cut into sheets after printing, comprising: - unwinding means (2) controlled by the strip (1), - a circulation path (3) of the unwound portion materialized by at least one bearing surface (3) adapted to form at least a portion of a plane (3) said plan Io support d printing, - at least one printing member (5), such as an inkjet printing head, arranged along the circulation path (3), means for moving (6) the web between an initial position (PI) and a final position (PF) acting on or near the end (8) of the strip located downstream of the bearing surface (s) (3) taken from the flow direction of said strip (1), and - cutting means (10) of the strip (1) after the printing phase, characterized in that the displacement means (6) are formed p by tension means (6) which, from said initial position (PI) to said final position (PF), permanently bias said strip (1) in tension, by the exercise of gravitational, or elastic, or magnetic forces.   2. Device according to claim 1, characterized in that it comprises motorized control means (4) for returning the displacement means (6) 25 to the initial position (PI), said motorized control means (4) being inactive. when moving the displacement means (6) from the initial position (PI) to the final position (PF).   3. Device according to claim 2, characterized in that the tensioning means (6) comprise gripping means (7) of said end (8) of strip (1) located downstream of the bearing surface (s). (3) taken in the direction of flow of said web (1), said gripping means (7) being controlled in displacement between a gripping position (PP) of the downstream end of the web and a release position (PL) ) of the band (1) by means of the motorized control means (4) for returning the displacement means (6) to the initial position (PI).   4. Device according to one of claims 2 and 3, characterized in that the cutting means (10) are controlled in operation by means of said motorized control means (4) return motorized moving means (6) in initial position (PI).   5. Device according to one of claims 1 to 4, of the type in which the tensioning means (6) comprise gripping means (7) of said end (8) of strip (1), characterized in that the means tensioners (6) carry the gripping means (7) and the cutting means (10).   6. Device according to one of claims 1 to 5, characterized in that the tensioning means (6) form ballast means (6) of the strip (1).   7. Device according to claim 6, characterized in that the tensioning means (6) comprise a pivoting main structure (11) mounted between the initial position (PI) and the final position (PF), freely pivoting around an axis (A11) substantially orthogonal to the unwinding direction of the strip (1), said main structure (11) being returned to the initial position (PI) by said motorized control means (4).   8. Device according to claim 7, of the type in which the tensioning means (6) comprise gripping means (7) of said end (8) of strip (1), characterized in that the tensioning means (6) comprise a movable secondary structure (12) movably mounted relative to the pivoting main structure (11) to be moved towards or away from said pivoting main structure (11) so as to form the gripping (7) and cutting (10) means; ) of the band (1).   9. Device according to one of claims 3 to 8, characterized in that said motorized control means (4) are formed of a rotary cam (15) driven in rotation by a motor (26), said cam (15) having a profile (16) designed to activate or deactivate the gripping means (7), and being provided with a finger (18) adapted to abut against a member (19) of the displacement means (6) in order to moving the displacement means (6) from said final position (PF) to said initial position (PI).   10. Device according to one of claims 1 to 9, characterized in that it comprises means, such as an electromagnet, retaining (20) temporary displacement means (6) in the initial position (PI ).   11. Device according to one of claims 2 to 10, characterized in that it comprises a rolling means (23), such as a wheel, wheel, or roller counter-rotating relative to said main structure (11) pivoting displacement means (6), so as to avoid driving the band (1) by said main structure (1'1) pivoting, upon returning the displacement means (6) to the initial position (PI).   12. Printing terminal delimiting an enclosure housing a device 20 for printing a flexible web (1) of a printable material, such as paper, stored in a roll, characterized in that the printing device conforms to the one of claims 1 to 11.   13. A method of printing a flexible web (1) of a printable material, such as paper, stored in a roll, comprising: - a step of gripping the downstream end (8) of the web (1) taken in the direction of circulation of said strip, - a step of unwinding a predetermined length of the strip (1), and - parallel to the unwinding of the strip (1), a step of moving and printing the strip portion (9) unwound from the strip (1), between an initial position (PI) and a final position (PF), this moving and printing step being followed by a step of cutting the strip (1) in sheet, characterized in that, for the displacement of the strip (1) from said initial position (PI) to said final position (F'F), said strip (1) is permanently stressed by force exertion gravitational, or elastic, or magnetic.