Device for jogging sheets.

The present invention relates to a device for aligning plate-shaped elements or sheets, used in an infeed station of a working machine such elements for the production of packages, as defined in the preamble of claim 1.

In printing machines or cutting of cardboard sheets, they are generally fed by batteries placed successively in the infeed station. Each stack is often not strictly vertical or exactly centered on the axis of the machine. Therefore, each cardboard sheet, after separation of the successive stack from the top or from the bottom, is introduced individually in a lateral aligning device and front to its exact position with respect:<ul><li>either of gripper bars mounted on a chain train and for transporting each sheet through cutting and ejecting waste stations which follow;</li><li>or to a printing station input rollers, for example by flexography.</li></ul>

To this end, such machines generally comprise an infeed station with feed table provided with a passage whose length, in the sheet running direction, is at least equal to the maximum size of sheets to be processed. Once a sheet from the feed table, it is stopped by front margin stops. Then, a pair of rollers or upper and lower rollers clamp an edge of the sheet and, by rotation, laterally pulls against a lateral jogging ruler. The axis of rotation of the two rollers is oriented substantially perpendicular to the sheet running direction. It should be noted that the lower roller, driven in rotation, is held in a fixed horizontal plane, while the upper roller, free to rotate, can occupy a first position in which it is not in pressure contact with the sheet and a second position in which it presses the sheet toward the lower roller.

The major drawback of such a side and front jogging device is that it requires a complete shutdown of the sheet. This judgment of the sheet, and then it is started, first, require relatively complicated control means and, secondly, are difficult to reconcile with current production rates ever higher since such a stop increases necessarily the cycle necessary for the operation margin.

Moreover, it is already known to produce continuously aligning a sheet which passes through a pair of rolls of the lower roller is rotated in the direction of travel and the upper roller, free to rotate is slightly skewed relative to the direction of travel. However, the upper roller on the one hand, this premature wear since, vulcanized, it is not driven and, secondly, has a tendency to till the sheet at the first contact when the roller is in the stop. It should be noted that in this case the sheet is usually driven by the rear using aids. Moreover, the aligning devices known to date have the disadvantage of requiring to provide two reference lines on the sheet, one on the trailing edge for taking gripper bars in the cutting stations, upsetting and / or embossing and the other on the front edge to the printing roller, which requires inversion of 180 ° of the sheet during the passage of a printing station to a cutting station.

The present invention therefore aims to eliminate the drawbacks mentioned above. This object is achieved by a jogging device according to claim 1.

We will now describe one embodiment of the invention with reference to the accompanying drawings wherein:<ul><li>1 shows a longitudinal sectional view of a lateral aligning device;</li><li>2 shows a top view of Figure 1;</li><li>3 shows a cross-sectional view along B - B of Figure 1;</li><li>4 shows a longitudinal sectional view of a front-end aligning device; and</li><li>5 shows a detailed view of an aligning roller mounted on a pivotable support.</li></ul>

Figure 1 shows a pack of sheets F which last less is taken by a suction table Ta to be transferred between two great R1 rolls R2 for, as soon as the Ta table released the sheet F, pull it out of package background for introduction into the longitudinal passage of a feeder table M. This passage is bounded by six pairs P1 - P3 lower rollers 1 and 2. Each upper lower roller 1 is located below the passage of the sheet, each upper roll above. The six pairs P1 - P3 are divided into two groups, one of which is located on the lateral side driver, and the other from opposite lateral side driver. 3 pairs P1 - P3 of each group are distributed over the entire length of the table, that is to say a first pair P1 is located at the upstream (relative to the direction of movement of the sheet F) the second P2 and third in the middle and downstream. The length of the feeder table M is at least equal to the maximum format of sheets to be processed.

To facilitate understanding, in FIG 2, only the lower rollers 1 are shown on the left; on the right, only represented the upper rollers 2.

The lower rollers 1, smooth steel, are intended to support and transport the sheet F. All lower rollers 1 of the same group, rotatably mounted on a side bar 10 (Figure 2) are extended from the free side by an end shaft 11 on which is mounted a toothed pulley 12 keyed into engagement with a toothed belt 13 driven in movement by a toothed pulley 14 provided at the upstream end of the lateral bar 10. to permit removal of the table a M sheet F to be defective, the lower rollers 1 are retractable so as to drop the sheet down. To this end, the downstream end of the bar 10 is mounted in free rotation about a horizontal axis 17 on a vertical plate 16 through a pin 16g for supporting; the upstream end is fixed to an intermediate block 16a, which is itself freely rotatably mounted on a thick vertical block 167. A first pair of bevel gears mounted within the intermediate block 16a, (shown in broken lines) and a second pair mounted in the vertical block 167 permit, from a square cross-bar 70 of motion transmission which meshes with a bevel gear of the second pair, the rotation of the pulley 14, as well as the tilting of all the lower rollers 1 around the axis 17. the square bar 70 is rotated at one end (by means not shown).

The pivoting of the lateral bar 10 about the axis 17 is achieved by means of a set of connecting rods 18a, 18b and a cylinder V1 located below the lateral bar 10.

The upper rollers 2 primary function of contributing to transport the sheet F in the direction of travel, that is to say of the press towards the lower roller 1, and a second function which is that of lateral aligning itself said, that is to say to move the sheet that scrolls toward one of the two rules side stopper 100 provided on each side of the table M. It turned out that to give each upper roller 2 the possibility of this dual function, it is necessary that each of them:<ul><li>can occupy a first position in which it allows each sheet F to readily penetrate between the two rollers 1, 2 constituting a pair P1 - P3, and a second position in which it pushes the sheet F towards the lower roller 1 in order it moves in the direction of travel;</li><li>is rotated with a peripheral speed equal to that of the lower roller 1, but the direction of which can be either of bias, that is to say a slight angle of 5 ° to 10 ° relative to that of the scrolling (or the axis of the machine), for the side guide, in parallel with that of the scrolling.</li></ul>

To this end each upper roller 2 is mounted (see Fig. 5) on a first support with four flanges which form two pairs brackets 20a, 20b opposite and perpendicular to each other. Between the flanges of the first bracket 20a, is mounted an upper roller 2 so that its axis of rotation is substantially perpendicular to the scrolling. An intermediate support 21 enters a free end inside the second yoke 20b. The first support 20 is mounted for free pivoting on the auxiliary support 21 by means a vertical axis 22 located in the central part between each bracket 20a, 20b. The auxiliary support 21 is provided with a hollow cylindrical portion 21a secured and centered on the end of a cylindrical support 25 pivotally mounted about its horizontal axis, on a side plate 200 extending over the entire length of the feed table M. A vertical rod 23 connects each flange of the second yoke 20b. Against this rod 23 abuts the outlet end 24 of a pneumatic cylinder V2 provided inside and on the axis of the swivel bracket 25. The ram V2 is operable to exert a certain force on the rod 23 of so as to rotate the dual bracket 20 about the axis 22 and thus to the upper roller 2, against the force exerted on it by the sheet which runs at a slight angle relative to the direction of scrolling. Controlling the actuator V2 is designed so that the roller 2 becomes again parallel to the scrolling when the force exerted by the sheet F is above a certain force, which is the case when the sheet F abuts against the side jogging rule 100 and its moving direction has no transverse component. Opposite the piston 24 of the ram V2 is provided a screw 26 fixed to the auxiliary support 21 and against which abuts the rod 23 to limit the pivoting of the caliper 20 in the direction of the roller 2 whose position is slantwise.

A lever 27 composed of a central part fixed in rotation on the swivel bracket 25 and extended through both a vertical arm 27a and a horizontal arm 27b, each provided at its free end with a roller 28a, respectively 28b, is used to control the degree of pivoting of the support 25. the roller 28b of the horizontal lever 27b abuts against an inclined surface of a stopper 29 fixed on a movable side bar 29a on which are mounted the stops 29 all of the same group of upper rollers 2. longitudinal movement of the rod 29a, it is possible, thanks to the inclined surface 29 stops, adjust the height of the working position of the upper rollers 2, that is to say the position in which they must press the sheet F against the lower roller 1. the movement of the bar 29a is obtained by means of a motor M2 driving a screw 29c into engagement with a corresponding thread of a bracket 99 fixed below the bar 29a. 28a on the other roller may act the outlet end of a pneumatic cylinder V3 which forces the lever 27 to pivot in a direction which maintains the roller 28b in contact with the stop 29. The cylinder V3 is successively put into action, as soon as the downstream edge of a sheet has entered between the two rollers 1, 2 constituting a pair P1 - P3, and put out of action or when the upstream edge has left the two rollers 1, 2 in order to facilitate penetration of the front edge of the next sheet, or when the sheet has been gripped by a gripper bar or rollers 93 and 94 of the device of Figure 4 described below. 28c a spring keeps the roller 28a against the output rod of the cylinder V3.

Vulcanized periphery of each upper roller is provided with small grooves 2b of elasticity, cooling and wear control, along with a semicircular radial groove 2a for engagement with a round endless belt of drive (not shown) connected to a corresponding auxiliary pulley 50 located nearby. The provision of each top roll 2 and of the auxiliary pulley 50 is such that the belt can perform its driving function without being obstructed by the light obliquely positioning of the roll 2. The auxiliary pulley 50 is mounted keyed on the first end a shaft mounted for free rotation on a side plate 300 of the feeder table M, the other end being mounted keyed a toothed pulley 51 engages an endless belt (not shown) common to all the upper rollers 2 of the same group and driven in movement by a pulley 52 rotated by the drive shaft 70.

The downstream end of each plate 200 is fixed by means of screws 169, the bracket 16, while the upstream end is fixed to the vertical block 167. In order to adapt the width of the feeder table M to that of size of the sheet F, each downstream support 16 is transversely displaceable by means of rollers 181 bearing on a rail 168 of the machine, and each upstream vertical block 167 using a roller 184 bearing on a rail 186. the two side plates 200, 300 are interconnected by horizontal struts 201. It should be noted that the upper roll 2 located at the upstream end is rotated by an endless belt connected to a pulley 50a mounted -Dessus of the transmission shaft 70 and driven by the latter by means of a pair of gear contained in the vertical block 167 (Figure 1 dotted). Adjusting the width of the feeder table M is effected by means of a screw 188 acting on each vertical block 167.

Above it has been described that the lateral aligning device comprises a first group of three pairs P1 - P3 rollers 1, 2 located on the driver side, and a second group on the side opposite the driver. This proved useful in order to realize the jogging the sheet F compared to a 100 located on both the rule either side, as required. Clearly, if jogging is performed according to a rule 100 located on the side opposite the driver, the upper rollers 2 pairs of P1 - P3 located on the driver side are maintained continuously in the rest position. Thus it is also possible in principle to provide only one group of pairs P1 - P3 rollers 1, 2 distributed along only one side over the entire maximum length of working format.

The front-end aligning device shown in Figure 4 is located directly after the side stopper described above, that is to say that the film F comes out of the lateral aligning device and simultaneously enters a passageway 80, formed by two guide plates 81 and lower than 82, the front jogging device.

The front guides is achieved by means of two movable stops 9 are each mounted on an endless timing belt 90. The two movable stops 9 are transversely offset. Thereafter, a single stop 9 will be described since the other tab is identical to it.

The toothed belt 90 describes a closed loop feedback from the top and which go from the bottom is parallel to the passageway 80. The belt 90 is guided to the upstream, that is to say at the input of the sheet F, by a pair of pulleys 90a and lower upper 90b, and downstream by another pair of lower pulleys 90c and upper 90d. The upper 90a downstream pulley is used to drive the belt 90. The two belts 90 are of course driven at the same speed. For the upper 90b upstream pulley is provided a tensioner 900.

There is provided one cam 9 of each belt 90. The tab 9 is provided with a bearing face 9a against which will abut the front edge of each sheet F when it is pushed forward at a speed v1 by reels 1, 2 prior device side stopper. The speed v1 is greater than v2 moving the movable plug 9 (or band 90). In other words, dimensions and velocities v1, v2 of the set are chosen so that each sheet jogging F, the tab 9 penetrates speed v2 first in the passageway 80, then followed by the sheet F which the front edge will abut against the rear face 9a of the stop since v1&gt; v2.

In order to ensure to the sheet F, when the tab 9 is leaving the front edge of the sheet F at the lower front pulley 90a, a displacement at a velocity v2, to said pulley 90c is coaxially associated a drive roller 93 whose peripheral speed is v2 and in collaboration with a pressure roller 94, located below the sheet F, causes the leaf out of the front jogging device and direction, for example, a station printing station relative to which it is easy to know exactly the longitudinal position of the movable plug 9 with reference to the rollers 93, 94. the pressure roller 94 is mounted on a balance in order to adjust the distance between the two rollers 93, 94 depending on the thickness of the sheet F.