EP1369213B1 - Apparatus for separating attachment points connecting piled cardboard sheets - Google Patents

Abstract

The device has a horizontal support chassis and a transportation unit (8,9,34a, 6,30) for moving stacked sheets of cardboard in a longitudinal direction. Another support chassis and transportation unit (16, 19) are included for moving the sheets in a transverse direction. A jack (35) serves to move apart a part of the support chassis and transportation unit, and a clamping unit is provided on both sides of the sheets.

Description

The present invention relates to a device for severing fastening points connecting two edges of a cutting line of stacked cardboard sheets laid on horizontal support and transport means for moving said sheets in a longitudinal direction, comprising upper clamping means for clamping the sheets stacked against said support means, first means for longitudinally spacing said support and transport means and said clamping means on either side of a cross-sectional line of said stacked sheets and second means for transversely spacing said support and clamping means on either side of a longitudinal section line.

Devices of this type are used in particular in the manufacture of cardboard boxes obtained by folding pre-cut and ribbed cardboard blanks formed from cardboard sheets.

Such devices for separating stacks of pre-cut sheets by clamping the stacks of sheets on either side of the precut line and pulling to break the points of attachment connecting these sheets exist. One of them is described for example in FR 2'372'025. However, this device is limited to cutting stacks of leaves on either side of a transverse line. However, in most cases, in particular during the manufacture of small packages, a plurality of cardboard blanks are arranged side by side, both in the direction of the length and the width of the cardboard sheet, so that It must be possible to separate the stacked cardboard sheets not only in the transverse direction, but also in the longitudinal direction of these sheets.

A device that includes the features of the preamble of claim 1 is described in the CH-A-646 665 .

It has already been proposed in the CH 646'665 a device for performing separations in two directions perpendicular to each other, in the direction of the length of the cardboard sheets and in the transverse direction, without the need to turn the sheets 90 ° after a first cutting. For this purpose, this device comprises four support tables aligned two by two transversely and longitudinally with respect to the direction of movement of the piles of cardboard sheets. These four tables are associated with four pressing members and can be separated from each other. others both longitudinally and transversely to effect separations between stacks of leaves.

This device has certain disadvantages, as well as limitations. Among the disadvantages is the fact that the separation along two lines perpendicular to each other is carried out by moving the tables and the pressing members in a direction forming an angle of 45 ° with respect to the two lines of separation. . The force required is greater than that which would be if it were directed perpendicular to each of the lines of separation. Therefore, the batteries should be tightened more tightly with the risk of marking the cardboard sheets at the ends of the batteries.

The limitations of the device come from the fact that it allows to perform a separation transversely to the direction of movement of the cardboard sheets. However it often happens that it is necessary to perform a greater number of separation especially when producing small packages for cigarette packs or bottles of perfume for example.

The object of the present invention is to overcome, at least in part, the disadvantages of the aforementioned solutions.

To this end, this invention relates to a device for breaking attachment points connecting two edges of a cutting line of stacked cardboard sheets laid on horizontal support and transport means for moving said sheets in a longitudinal direction. according to claim 1.

The main advantage of this invention lies in the fact that it allows the production of an unlimited number of cardboard blanks in the direction transverse to the direction of main or longitudinal displacement of the stacks of sheets.

Preferably, the transverse transport means of the stacked sheets are flexible elements whose two ends are fixed to the supports of the longitudinal conveyor and pass on the transverse supports after being passed around two pulleys fixed to the ends of these transverse supports.

As a result, when the carriers of the longitudinal conveyor are moved laterally in one direction, the portion of the flexible member passing on the transverse supports moves in the opposite direction. Thanks to these displacements in opposite directions, the length of the transverse displacement of the supports of the longitudinal conveyor is added to that of the displacement of the stacked sheets, so that the relative displacement to bring the separation lines of sheets stacked between the two supports of the longitudinal conveyor to separate them is twice as large as the actual displacement of each of them. This makes it possible to reduce the width of the device in order to break the points of attachment between the stacked sheets with respect to a system in which the support of the longitudinal conveyor is fixed in the lateral direction, or a system in which the stacked sheets are fixed in the lateral direction.

• La figure 1 est une vue en élévation latérale de cette forme d'exécution;
• la figure 2 est une vue en coupe transversale de la figure 1;
• la figure 3 est un schéma de principe de la figure 2 montrant la rupture des points d'attache s'étendant selon une ligne essentiellement longitudinale au sens d'avance des feuilles empilées;
• la figure 4 est une vue semblable à la figure 3 montrant le déplacement des feuilles empilées transversalement au sens d'avance des feuilles empilées;
• la figure 5 est une vue semblable à la figure 3 montrant la rupture des points d'attache selon une ligne essentiellement parallèle à celle de la figure 3;
• la figure 6 est un schéma de principe de la figure 1 montrant la rupture des points d'attache s'étendant selon une ligne essentiellement transversale au sens d'avance des feuilles empilées.

Other features and advantages of the device object of the present invention will become apparent from the following description which will be made with the aid of the accompanying drawings which illustrate schematically and by way of example, an embodiment of the device to break attachment points connecting two edges of a cut line of stacked cardboard sheets.

• The figure 1 is a side elevational view of this embodiment;
• the figure 2 is a cross-sectional view of the figure 1 ;
• the figure 3 is a schematic diagram of the figure 2 showing the breaking of the attachment points extending along a substantially longitudinal line in the direction of advance of the stacked sheets;
• the figure 4 is a view similar to the figure 3 showing the displacement of the sheets stacked transversely to the direction of advance of the stacked sheets;
• the figure 5 is a view similar to the figure 3 showing the breaking of the attachment points along a line essentially parallel to that of the figure 3 ;
• the figure 6 is a schematic diagram of the figure 1 showing the breaking of the attachment points extending along a line substantially transverse to the direction of advance of the stacked sheets.

The device illustrated by the figures 1 and 2 comprises a frame 1 on which are mounted endless belt conveyors 2, 3 and 4. The conveyors 3 are arranged side by side in the direction transverse to the direction of movement of the stacked sheets 5, as can be seen on the figure 1 . The conveyor 4 extends over the entire width of the conveyors 3, downstream of the conveyor 2.

The conveyor 2 comprises an endless conveyor belt 6, visible on the figure 1 , which is driven by a motor 7. The conveyors 2, 4 each further comprise a support frame 8, respectively 9, which is slidably mounted by rollers 10 engaged with a transverse guide and support rail 11, integral with the frame 1. These two support frames 8, 9 are connected transversely to each other by a jack 12 (see figure 2 ). A motor 13 secured to the support frame 8 drives a wheel 14 in engagement with a rack 15 secured to the transverse rail 11, thereby displacing the two support frames 8, 9 along the transverse rail 11.

As illustrated by figure 1 the horizontal portions of the conveyor belts 6 of the conveyors 2, 4 forming the support and transport part of the stacked sheets 5 are guided by a series of rollers 37, arranged to create a succession of open loops 6a which extend to below the upper support surface of the chassis 8, 9 and the latter are also shaped to leave free spaces within these open loops 6a. Support members 16 and transverse transport 3 stacked sheets 5 are housed in these loops 6a. The horizontal portions of the conveyor belts 6 extending between the guide rollers 37 rest on support surfaces 38 secured to the frames 8, 9 of the conveyors 2, 4. Thanks to this arrangement, the support surface of the stacked sheets 5 is greater than that provided by rollers alone, which reduces the risk of marking the sheets of cardboard, following the tightening of the batteries 5

These support members 16 and transverse transport 3 have the shape of elongated pads which extend over the entire width of the conveyors 3 arranged side by side and the two ends of these conveyors 3 are integral with two supports 17a, 17b which are connected to cylinders 18a, 18b of which only two are visible on the figure 2 . Each pad or support member 16 is shaped to guide a flexible conveying element 19 constituted, in this example, by a belt segment of circular section whose two ends are respectively fixed to the frames 8 and 9, after this belt has passed. around two pulleys 20a, 20b secured to the supports 17a, respectively 17b.

With this arrangement, the upper part of the belts forming the flexible transport elements 19 is driven by the chassis 8, 9, moved under the action of the motor 13 and the wheel 14 in engagement with the rack 15, in the opposite direction of displacement of these frames 8, 9. As a result, the relative displacement between the stacked sheets 5 and the chassis 8, 9 which support them is twice the actual displacement of these frames 8, 9 and flexible elements of transport 19.

This multiplication by two between the length of the actual displacement and that of the relative displacement substantially reduces the width of the device according to the invention. Indeed, in a practical example where a maximum stroke of 160 cm is necessary, the actual displacement is only 80 cm, so that the width of the device is reduced by 80 cm.

The upper part of the device is substantially symmetrical to the lower part which has just been described. It comprises two clamping members 21, 22 arranged side by side in the transverse direction of the device, as illustrated by FIG. figure 2 and connected by a jack 25. Preferably, the dimensions of these clamping members 21, 22 respectively correspond to those of the frames 8, 9 to enable them to press the stacked sheets 5 against these frames 8, 9.

For this purpose, these clamping members 21, 22 are slidably mounted by means of rollers 24, on two transverse rails 23a, 23b respectively mounted on two opposite sides of the frame 1. Each transverse rail 23a, 23b is itself mounted sliding vertically and controlled by two cylinders 26a, 26b.

As the frames 8, 9, the clamping members 21, 22 are integral with a motor 27 for driving a gear 28, in engagement with the racks 29 secured respectively to the transverse rails 23a, 23b. The motors 13 and 27 are slaved to each other so that each displacement of the chassis 8, 9 corresponds to a displacement of the same value and in the same direction of the clamping members 21, 22.

The conveyor 4 located at the exit of the conveyors 2, also comprises an endless conveyor belt 30, extending over the entire width of the conveyors 2, 3. This conveyor belt 30 is driven by a motor 31. This conveyor 4 also comprises a clamping member 32. The whole is secured to a frame 34a, 34b hinged about a transverse axis 33 secured to the guide rail 23a. A jack 35 serves to rotate the frame 34a, 34b about the transverse axis 33.

To allow the displacement of the clamping member 32 with respect to the upper horizontal part of the conveyor belt 30, the 34a, 34b frame consists of two parts, a lower portion 34a, carrying the conveyor 4 and an upper portion 34b carrying the clamping member 32. The lower portion 34a has, on each side of the conveyor 4, four guide rollers 36 , defining a vertical slide, between which the upper portion 34b is slidably mounted, allowing on the one hand, this upper portion 34b to slide relative to the lower portion 34a, when the clamping member 32 is to clamp stacked sheets 5 against the conveyor belt 30 and on the other hand, the tilting of the lower and upper parts of the frame 34a, 34b around the transverse axis 33 under the action of the jack 35.

The operation of the device which has just been described will now be explained using the figures 1 and 2 . As to the different possibilities offered by the mechanism described in detail with reference to figures 1 and 2 they will be explained using the simplified diagrams of Figures 3 to 6 with the understanding that we can always refer to figures 1 and 2 for the details of realization of the device.

When a stack of pre-cut sheets 5 to be separated is brought onto the conveyors 2 and 3, these are in the position illustrated by FIG. figure 2 , centered in the direction of the width of the frame 1. If the stack 5 is first to be separated into two equal parts in the width direction, it is sufficient to tighten it between the conveyors 2, 4 and the clamping members 21, 22 using the four cylinders 26a, 26b. Once a suitable clamping force is exerted, the actuators 12 and 25 are actuated to separate the frames 8 and 9 from the conveyors 2, 4 and the clamping members 21 and 22. The force thus exerted on the stack 5 makes it possible to break the attachment points left when pre-cutting the stacked cardboard sheets, as illustrated by figure 3 .

When each half of the stack 5a, 5b must itself be subdivided into two or more parts, the procedure is as follows. First of all, the clamping members 21, 22 are lifted by means of the jacks 26a, 26b. Then the skids 16 secured to the support bars 17a, 17b are lifted using the jacks 18a, 18b ( figure 2 ), so as to separate the stacks 5a, 5b longitudinal conveyors 2, 4. The stacks 5a, 5b then rest on the conveyor belts 19 supported by the pads 16.

The chassis 8, 9 are then moved with the aid of the motor 13 and the wheel 14 in engagement with the rack 15, as well as the clamping members 21, 22 with the aid of the motor 27 and the wheel 28 in engagement. with the rack 29. These two displacements have the same meaning and the same length. This length corresponds to half the transverse distance between the cutting line along which the pile 5 has just been separated and the cutting line along which the following separation must be made. Indeed, since the ends of the conveyor belts 19 are secured to the frames 8, 9 and pass over the pulleys 20a, 20b, the displacement of the frame 8, 9 in one direction causes the reverse movement of the upper parts of the belts. 19 on which rest the batteries 5a, 5b, so that these piles move in the opposite direction to that of the chassis 8, 9. As a result, the relative transverse displacement between the batteries 5a, 5b and the chassis 8, 9 is two times greater than the actual displacement of each of them.

This position is for example that which is illustrated by the figure 4 . A new separation of the stack 5a can then be performed as described above, the stack 5b not being separated, as illustrated by the figure 5 .

Other separations are possible. In the case illustrated, the battery 5b could then also be separated in two. It would then suffice to move the chassis 8, 9 in the opposite direction to bring the middle of the stack 5b between the two frames 8, 9 and between the two clamping members 21, 22. With this device, it is possible to realize small stacks of boxes from a stack of sheets of large width since it is then enough to divide the stack into as many stacks smaller than there are cut lines in the width of the initial sheet.

To divide the stacks thus formed according to the cutting lines substantially transverse to the direction of longitudinal advance of the stacks 5a, 5b, 5c, 5d ..., it is sufficient to advance these stacks to bring a cutting line between the longitudinal conveyors 2 , 4 and the transverse conveyor 3. It then proceeds as before, by lowering the clamping members 21, 22 and 32 with the cylinders 26a, 26b. Actuator 35 is then actuated to pivot frame 34a, 34b around axis 33 to bring it into the position illustrated by FIG. figure 6 and thus cause the breaking of the attachment points to form a new stack 5'a from the stack 5a. At the same time, cells 5'b, 5'c, 5'd (not shown) are formed. The following separations are obtained by bringing the conveyor 4 into horizontal position by retracting the rod of the jack 35 into its piston and lifting the clamping members 21, 22, 32 and then discharging the piles 5'a, 5'b, 5 'c, 5'd and advancing the remaining piles located on carriers 2, 4 to the next cut line and repeating the same operation.

Claims (6)

1. Device for breaking nicks connecting two edges of a cutting line of stacked cardboard sheets (5) comprising

   - first horizontal support and conveyor means (8, 9, 34a, 6, 30) for supporting and moving said stacked sheets (5) in a longitudinal direction,

   - upper clamping means (21, 22, 32) for clamping the stacked sheets (5) against said first support and conveyor means (8, 9, 34a, 6, 30),

   - first means (35) for longitudinally moving aside said first support and conveyor means (8, 9, 34a, 6, 30) and said clamping means (21, 22, 23) on both sides of a transverse cutting line of said stacked sheets (5), and for breaking nicks extending along the cutting line transverse to the running direction of the stacked sheets (5),

   - second means (12, 25) for transversely moving aside a part of said first support and conveyor means (8, 9) and said clamping means (21, 22) on both sides of a longitudinal cutting line of said stacked sheets (5), and for breaking nicks extending along the cutting line longitudinal to the running direction of the stacked sheets (5),

   characterized in that it includes second horizontal support and conveyor means (16, 19) for supporting and moving said stacked sheets (5) in a direction transverse to the running direction of the stacked sheets (5), so as to enable the separation of the stacked sheets (5) into more than two smaller piles in the width of the initial sheet owing to the second means for moving aside (12, 25).
2. Device according to claim 1, wherein said second horizontal support and conveyor means (16, 19) are fixedly attached to means (17a, 17b, 18a, 18b) for moving them vertically between at least two positions, one in which they are at a lower level than the level of the first horizontal support and conveyor means (8, 9, 34a, 6, 30) for moving said stacked sheets (5) in a longitudinal direction, the other position in which they are at a higher level than said first horizontal support and conveyor means (8, 9, 34a, 6, 30), which are fixedly attached to lateral movement means (13, 14, 15) to allow to set the location where said first horizontal support and conveyor means (8, 9, 34a, 6, 30) have to separate, opposite said longitudinal cutting line of said stacked sheets (5).
3. Device according to one of the preceding claims, wherein said second horizontal conveyor means (16, 19) include at least one flexible element (19) extending over the whole length of said second support means (16) and passing around two pulleys (20a, 20b) extending laterally to the respective ends of said second support means (16), the respective ends of said flexible element (19) being fixedly attached to said first horizontal support means (8, 9), such that when they move laterally in one direction, the part of said flexible element (19) extending over said second support means (16) moves laterally in the other direction.
4. Device according to one of the preceding claims, wherein said first horizontal conveyor means (6) include at least two endless conveyor belts located on both sides of the location where said first horizontal support means (8, 9) have to separate and that the upper parts of these conveyor belts (6) extending over said first support means (8, 9) .form at least two open transverse loops (6a) extending below the level of said first support means (8, 9), said second support and conveyor means (16, 19) being arranged in said open transverse loops (6a).
5. Device according to claim 4, wherein the horizontal portions of said conveyor belts (6) extending between two of said open transverse loops (6a) rest on planar bearing surfaces, fixedly attached to said first support means.
6. Device according to claim 1, wherein said horizontal support and conveyor means (8, 9, 34a, 6, 30) for moving said stacked sheets in a longitudinal direction and said clamping means (21, 22, 32) include two horizontal support and conveyor means (8, 9, 6) and two clamping means (21, 22) arranged side by side on both sides of a longitudinal separation and a support and conveyor means (34a, 30) and a clamping means (32) which extend over the whole width of said support and conveyor means (8, 9, 6) arranged side by side and are arranged downstream of the latter with respect to the longitudinal moving direction of said stacked sheets by said horizontal support and conveyor means (8, 9, 34a, 6, 30) for moving these sheets in a longitudinal direction.

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