EP1348524B1 - Device for supporting, fixing and reinforcing a flat tool in a station for stripping waste material in a cutting press - Google Patents

Abstract

The support bar (11) has fixing heads (14) projecting from its upper surface. Each head has a fish-hook type barb (17). These are introduced into holes (6) formed in the underside of the tool plate (10), and becomes embedded in the underside of the tool plate, thus retaining it in position. The support bar (11) has upper (19) and lower (20) surfaces, with a number of fixing heads (14) projecting from its upper surface. Each head includes a straight sided section (15) with a conical section (16) above. The conical section is narrower at the top and wider at the bottom, such that it is wider than the straight section, thus forming fish-hook type barbs (17). These are introduced into holes (6) formed in the underside of the tool plate (10), the holes having been formed by laser machining. The barbed support heads become embedded in the underside of the tool plate, thus retaining it in position. The tool plate may be made of wood, enabling rapid and accurate laser machining of the holes.

Description

The present invention relates to a support member, attachment and reinforcement of a plan tool used in an ejection station waste from a cutting press, used in the packaging industry especially.

Converting sheets of paper, cardboard or material plastic to obtain blanks of boxes, includes a suite of operations among which the sheets, apprehended one by one in their edge front by a series of pliers mounted along a transverse bar in moving, are taken to a cutting and crushing station then in an ejection station where the waste resulting from the cutting is removed from the sheet in one operation.

A plurality of poses, or blanks of boxes, can usually be cut from a single sheet. These poses are there represented flat in a developed form which, after folding and gluing, will form the expected packaging boxes. The contours of these poses are cut by cutting nets in the platen press, while the lines folding of these poses are marked by pressure nets during the same operation. To prevent the sheet from being broken once cut, cutting nets will have been cut in corresponding to each joint of adjacent cut sheet portions. As a result, all the poses remain fragile maintained between them by material bridges, called attachment points, spared from cutting by cuts made in cutter nets.

Although the arrangement of the poses on the sheet is made from the the most judicious way possible, it is generally not possible to avoid produce waste resulting from cutting. This waste consists of around the leaf and through the inner intermediate parts that separate the poses between them. All waste is removed from the sheet in the station ejection, for example by pinching between pairs of ejection needles which pull them down and then drop them in a tray or on a carpet discharge.

Such a station usually includes a mobile upper tool in the vertical plane equipped with ejectors, a perforated ejection board on which leaves come successively stop to be cleared their waste, and usually a lower tool collaborating with the tool upper to remove the waste from the sheet. Now, sometimes this inferior tool is not used; the waste is then ejected from the sheet only thanks to ejectors of the upper tool that push them down. In that case, the ejection is called "dynamic". At high speed, the ejection board is against strong vertical pressures because the waste, not being more pinched to be removed, should rest partially on the edges of the opening, planned for their ejection, with the aim of making them first and foremost down to simultaneously break all the attachment points that them connect to the sheet. Without this, some attachment points may not be broken, leaving the garbage then hanging through the openings of the board and cause an inevitable jamming during the evacuation of the sheet out of the ejection station. The solution to pinch the waste between the upper tool and a lower tool allows to guarantee, at very high speed, a perfect elimination of all waste from the sheet without any jam.

In a format similar to that of the sheet, the top tool is present in the form of a perforated board or a frame provided with several bars on which are mounted ejection needles which detach the waste from the leaf by pushing them down through the openings of the ejection board. Sometimes the top tool also includes pressers, constituted for example by small cubes of foam, which have for simple effect of keeping the poses of the leaf against the upper face of the ejection board. The lower tool includes ejecting needles telescopic arranged next to those of the upper tool. This provision allows precisely pinch the waste and remove them from the sheet, through the ejection board, during each cycle of the tool movable upper moving down, and this before the sheet is then taken out of the ejection station by the clip bar which always grabs his front edge. Such an ejection station is illustrated and described in more detail in CH689974.

It is on the board of ejection of such a station that the object of the present invention finds its use. Upper and lower tools as well that the ejection board are usually each arranged and fixed on a carrier frame that can be easily extracted from the ejection station in the horizontal plane in the manner of a drawer. Intended to support only poses of the sheet while allowing the removal of waste, the ejection board does not presents only rarely straight edges but has edges which reproduce the contours of the poses located on the periphery of the leaf. As a result, the ejector board can not be directly attached to its carrier frame by its upstream and downstream edges, or lateral, but requires to be mounted on longitudinal crosspieces or metal bars of fixed and adapted lengths to be placed and maintained in the carrier frame by their ends. These bearing bars usually have a rectangular section, the longer sides of which are oriented vertically for bending stiffness, and are fixed against the underside of the ejection board by screwed brackets, on the one hand against the flanks of these bars, and secondly in the board in question. The Patent CH575294 illustrates this mode of arrangement in its figures 2 and 3. However, this embodiment has several disadvantages, namely that, for their fixation, these bars require a multitude of small parts (brackets and hardware) that require drilling, fitting and relatively long assembly times. Moreover, this embodiment occupies, on the surface of the ejection board, a certain important place necessary for the fixing brackets. However, according to the shape of the poses of the boxes to cutting, the setting up of these squares can sometimes pose problems to the formist in charge of arranging the bearing bars between the openings of the ejection board; which openings can not of course be in any case obstructed, even partially.

The openings of the ejection board are directly dependent on the form poses and their arrangement on the sheet. It often happens that it is not possible to avoid the production of relatively large waste. As a result, the ejection board will be weakened even more waste has a large surface area or is numerous. Because of this, it is not rare to also have to strengthen the bending strength of this board by the addition of reinforcing bars fixed against its underside of the same way as the bars that carry it. For these bars reinforcement, generally of the same section as the bearing bars, can have an effective action on the rigidity of the ejection board, it is desirable that they be as long as possible, up to the amount of format of the board, avoiding as much as possible to fragment them in several pieces. However, to be able to fix such bars of reinforcement on the surface of the ejection board, it is often necessary to fold them several times until they take the form of a broken line to avoid all the additions imposed by the sheet in the board ejection. This meticulous work makes the realization of the ejection board difficult and more expensive still. Each ejection board being specific to a specific work, it will also be necessary to carry out such a craft work for each new ejection board. Given the large number of necessary pieces of hardware per board, these parts will usually be recovered just like the fixing brackets. However, the dismantling of a ejection board only adds to the cost of doing a job given.

To lower the costs of producing an ejection board, has already thought of replacing the usually metallic support bars, as well than those of reinforcement, by bars or sleepers of another material cheaper and can be glued like wood. However, being less solid metal, this material required in return a more dimensioning the thickness of load-bearing cross-members and sleepers enhancement. This oversizing had the disadvantage of occupying more space on the surface of the ejector board and therefore it even more difficult to have such ties while avoiding all the openings for the ejection of waste. The ends of the sleepers generally have a tapered shape, machined so that they can come into engagement with the fastening system provided on a frame carrier. The tapered profile of the ends of these sleepers, when they are in wood, weakens the latter which become delicate and require a special attention when handling the ejector board. Finally, because of their rapid wear, workshop tests have also shown that Such ejection boards soon became prone to progressive vibrations during prolonged use.

The object of the present invention is to equip a planar tool such an ejection board working in a station downstream of a press platinum, support members, fasteners and reinforcements not exhibiting the aforementioned drawbacks. For this purpose, these bodies must be able to made in a material with high rigidity and be cheap preferably. From a uniform production and standardized, these bodies must also be able to be almost ready to the use without requiring particular shaping, for example by folding of these. These organs must also be able to be fixed on the board ejection without any hardware or additional element, and this fastening must to be solid, almost instantaneous and not requiring any adhesive substance as a glue that requires some drying time or requires special handling if it is fast setting for example. Finally, these organs must also be the solution sought for the realization of a ejection board in an extremely reduced time and for such a cost, no recovery should be considered if no storage is planned for future reuse for identical work.

These objects are achieved by virtue of the present invention which has the object a supporting, fixing and reinforcing member in accordance with claim 1.

• La figure 1 est une vue de dessus d'une feuille sur laquelle les contours d'une pluralité de poses découpées s'y trouvent dessinés.
• La figure 2 est une vue de dessous d'une planche d'éjection ajourée sur laquelle la feuille de la figure 1 vient s'arrêter pour être débarrassée de ses déchets.
• La figure 3 est une vue en élévation d'une barre portante selon l'invention, fixée contre la surface inférieure de la planche d'éjection représentée en coupe verticale.
• La figure 4 est une vue partielle en élévation d'un autre mode de réalisation d'une barre portante, ou préférentiellement d'une barre de renforcement utilisée pour rigidifier la planche d'éjection fragilisée par ses ajours.
• La figure 5 représente la partie femelle d'un autre mode de réalisation de l'organe de la présente invention, utilisé principalement comme moyen de préhension pour maintenir la planche d'éjection dans son cadre porteur.
• La figure 6 représente, sur une portion de couronne, une pluralité de parties mâles du mode de réalisation illustré à la figure 5, destinées à venir se clipser dans la partie femelle pour fixer cette dernière à la planche d'éjection d'une façon simple et définitive.

The invention will be better understood from the study of an embodiment taken in no way limiting and illustrated by the appended figures in which:

• Figure 1 is a top view of a sheet on which the contours of a plurality of cut poses are drawn there.
• Figure 2 is a bottom view of a perforated ejector board on which the sheet of Figure 1 comes to stop to be cleared of waste.
• Figure 3 is an elevational view of a bearing bar according to the invention, fixed against the lower surface of the ejection board shown in vertical section.
• Figure 4 is a partial elevational view of another embodiment of a bearing bar, or preferably a reinforcing bar used to stiffen the ejection board weakened by its openings.
• Figure 5 shows the female part of another embodiment of the body of the present invention, used mainly as a gripping means for holding the ejection board in its carrier frame.
• FIG. 6 shows, on a portion of a ring, a plurality of male parts of the embodiment illustrated in FIG. 5, intended to snap into the female part in order to fix the latter to the ejection board in a simple manner and definitive.

Figure 1 shows the fragmentation of a sheet 1 in a multitude poses 2 and waste 3, which result from its division at the end of the action of a platen press in a cutting station. On the example given by this figure, are represented, in their expanded form, twelve poses 2 or cardboard box blanks arranged side by side on the sheet 1. In order to better distinguish each of these poses, they have been alternatively represented by two different hues. External features of each of these poses define the contour of the box developed, such it has been cut, while the inner lines correspond to the lines which have been marked by the pressure nets during the cutting. To be able to go from the cutting station to the station ejection of the waste, the sheet 1 is driven at its front edge by a clamp bar 4 moving in the direction of the arrow 5.

FIG. 2 represents, in a view from below, the plane tool of the ejection station, consisting of an ejection board 10 whose geometry corresponds to the layout of poses 2 of Sheet 1. Corresponding to this ejection board is also represented on this same figure, the sheet 1 as cut according to the contours of each pose 2. The around this sheet as well as the cutting lines of the poses are illustrated by broken lines, while the ejection board 10 is hatched to better distinguish its contours.

After leaving the cutting station, sheet 1 is stopped above the ejection board so that the poses 2 are in perfect location with the edges of openings 13 formed in the board. From this fact, all the waste 3 of the sheet 1 are located above the spaces perforations of the ejection board 10, or outside thereof for the waste located at the edge of a leaf. Thanks to the action of the upper and lower tools (not shown) of the ejection station, all the waste 3 can be removed from the sheet in one operation, either through the board openwork, either in its periphery. Once this operation is completed, sheet 1 spring of the ejection station, according to the direction given by the arrow 5, without dislocate thanks to the different points of attachment (too small to be illustrated) which still link all the poses 2 between them.

Against one of the surfaces of the ejection board 10, usually against its lower surface, are fixed load-bearing bars 11 which have for dual purpose of supporting the ejection board when introduced into machine in the ejection station and offer a means of grasping to capture and fix rigidly this board in the station ejection, usually via a horizontal support frame can be slid into a machine like a drawer. The ejection station and the supporting frame have not been deliberately represented in the figures annexed, because they do not relate directly to the subject-matter of this invention and do not provide any additional elements necessary for understand how it works

Between the two upper bearing bars, illustrated as examples in Figure 2, are also represented some bars of reinforcement 21 that allow to restore a certain rigidity to the board perforated ejection 10. Support bars 11 and reinforcing bars 21 are precisely part of the organ object of the present invention and will be described in detail in the following study.

FIG. 3 is an elevational view of a bearing bar 11, according to the invention, fixed against the lower surface of the ejection board 10 shown here in vertical section. This bearing bar 11 has a flat laminated geometry determining an upper edge 19 and a ridge lower 20. In order to be able to get fixed without play in the ejection board without the addition of any mechanical part attached to its sides, without the addition of rivets or hardware and without the addition of a substance or an adhesive element, this bearing bar 11 is provided along its edge upper 19, a plurality of fastening heads 14 each having a shape reminiscent of the tip of a hook. Each fixing head 14 has therefore a trunk 15 surmounted by an end portion 16 having at least one projection 17, preferably two, with respect to the vertical edges of the trunk 15. The latter have a length such that the end portion 16 is preferably completely embedded in the thickness of the ejection board once the bearing bar 11 correctly inserted. As represented in Figures 3 and 4, the end portions 16 have a trapezoidal shape. However, it goes without saying that these terminal parts could also take a rounded shape, rectangular or triangular for example.

So that the bearing bar can be inserted into the board ejection 10 without damaging the latter, openings 6 were previously laid out in this plate, in line with the locations of fixing heads 14. These openings may be made by means of a laser machining at the same time as are machined, by the same means, the openings 13 made in the ejection board. The latter being usually made of wood, laser machining does not cause any problem particular and brings the benefit of being fast, accurate and of utmost for the shaping of ejection boards commonly used in the field concerned by the present invention in particular.

Thus, to allow the assembly of the bearing bars 11 on the ejection board 10, it suffices to exert pressure on these bars, striking for example the lower edge 20 with the aid of a hammer or a mallet, until the upper edge 19 is completely pressed against the face lower part of the ejection board 10. Due to the shape of the projections 17, these prevent any removal of the bearing bar which is then solidly anchored in this board. Preferably, it is expected that the top surface of the fastening head comes slightly below the level of the upper face of the ejection board. However, it would be perfectly conceivable that this fixing head comes rather to touch the upper surface of the ejection board. So that this bar can be apprehended by the clamping device provided for the ejection board, at least one of the ends 18 of this bar is profiled accordingly.

FIG. 4 is a partial view in elevation of another embodiment of production of a bearing bar 11 or, preferably, as described below, a reinforcing bar 21 used to stiffen the ejection board weakened by his openings. This reinforcement bar also has a flat laminated geometry determining an upper edge 29 and a ridge In Figure 4, only the reinforcement bar 21 is represented. For the sake of clarity of the drawing, the ejection board 10 has not been drawn but is placed in the same way as before. Indeed, the fixing heads 24 of this reinforcement bar 21 are identical to the fastening heads 14 of the bearing bar 11 and fill the same role. Therefore, each of these heads 24 also includes a trunk 25 vertical, a terminal portion 26 and preferably two projections 27 disposed at the lower ends of the end portion 26.

The main difference that distinguishes the bearing bar 11 from there reinforcement bar 21 lies in the fact that the latter has horizontal oblong openings 31 and vertical 32, as well as openings in the form of a throat 33 machined at the base of each trunk 15 on each side of its two vertical edges. Horizontal oblong openings 31 are practiced at the base of the trunk 25, slightly below the level of the ridge superior 29.

Thanks to this horizontal oblong opening, it becomes possible to easily break the fastening heads 24 with a simple universal clamp. The position of this opening, slightly set back from the level of the ridge greater than 29, as well as the vertical bleeds brought by the throats 33 of on either side of the trunk 25, ensure that the breakage of the head of the fastening 24 will not interfere with the joining of the reinforcing bar against the face of the ejection board 10 at the time of its assembly.

The vertical oblong openings 32 also have the function of facilitate the cutting of the reinforcing bar 21 in places determined. These openings are regularly spaced is arranged between the fixing heads 24. They are advantageously centered in the width of the reinforcement bar. Their goal is to be able to segment, if necessary, the bar in several sections. As illustrated in Figure 2, it is generally necessary to segment a reinforcement bar into several elements in order to be able to arrange them between two bearing bars 11, for example, or between the openings 13 of the ejection board without these are not obstructed. According to the judicious location of such a bar of reinforcement and according to the shape and arrangement of the poses 2 on the sheet 1, the reinforcing bar portions may have varying lengths. Therefore, it is very advantageous to be able to easily cut a bar of strengthening in elements of different lengths according to his needs. Since the spacing of the fixing heads 24 is regular, invariable and known in advance, it is also easy to predict where will have to be operated the openings 6 allowing the passage of the fastening heads in the board 10. These openings 6 can be machined at the same time. than those laid down for bearing bars 11 and therefore at the same time as complete machining of the entire ejection board.

In order to use both reinforcement bars as bearing bars and vice versa, the reinforcement bars 21 are also provided with at least one end 28 profiled in the same way as the corresponding ends of the bearing bars 11. It goes without saying that end section of a reinforcing bar can both be used to its reinforcing function and for its function as a means of gripping the ejection board in the fastening device provided to maintain it in machine by said ends 18 and 28.

Depending on the arrangement and the sometimes particular shape of the poses 2 on sheet 1, it may happen that it is not possible to place bars 11 on the entire length of the ejection board or to place them in sufficient numbers. It can also happen that even the smallest stretch end of a reinforcing bar 21 is still too long and can not not be willing to a desired place on the ejection board to fill his function of gripping means. To mitigate this possibility, it is planned to another embodiment of the organ of the present invention, composed of two interlocking parts that are illustrated by the Figures 5 and 6.

FIG. 5 represents a claw 41 constituting the female part of this other fastener used mainly as a gripping means for maintaining the ejection board. The claw 41 also has a flat laminated geometry determining an upper edge 49 and a ridge lower 50. This claw consists of a split head 44, or split, into two end portions 46a and 46b by a wide and first opening 43 of trapezoidal shape. Excluding this opening trapezoidal 43, the attachment head 44 is quite similar to the heads of fixing 14 and 24 previously described. Thus, each end portion 26a, 26b respectively overcomes a trunk portion 45a, 45b while forming a projection 47 on each side of the fixing head 44. This fixing head is also intended to be drowned without play in the opening 6 made to its intention in the ejection board 10, as illustrated in FIG. right of this opening 6, this ejection board is based on two small consoles 53 forming a seat for the claw when mounted in the ejection board.

The trapezoidal opening 43, splitting the fixing head 44 in two parts of preferably symmetrical, opens on a second opening 42, arranged in the lower part of the claw 41, forming on each side a sharp angle 57. These two parts 51, 52 are joined at their lower ends by the lower edge 50 terminated at one end, at least by a foot 48. This foot constitutes, just as the ends 18 and 28 of the bars previously described, the gripping means interacting with the device attachment of the ejection board provided in the machine. Together, openings 42 and 43 can provide advantageous elasticity to both parts 51, 52 thus delimited.

In order to stiffen the attachment of the claw 41 in the ejection board, it is intended to insert a wedge, or clip 61 represented in broken line in the FIG. 5, through the trapezoidal opening 43. For this purpose, FIG. a plurality of clips 61, arranged on a crown portion 64, and each constituting the male part to fit into the claw 41. Each of these clips is connected to the crown, or crown portion 64, by a thin bridge of material 65 so that it can be easily detached manually.

Each clip consists of two parts, one 63 and the other lower 62. The upper portion 63 is intended to be adjusted in the trapezoidal opening 43 of the claw 41 and the lower portion 62 to be inserted simply in the second opening 42 coming to hang against the part angular 57 at the junction of the two openings 42 and 43. To do this, the part 63 of the clip 61 has the same trapezoidal shape as that of the opening 43. The lower part 62 is also trapezoidal in shape without this is not a necessity. This lower part 42 constitutes makes the head of the clip 61 and looks, both in its form and in its function, to the fixing heads 14, 24 or 44 described above. So the part lower section has two protrusions 67, formed by the join of parts 62 and 63.

Once the clip 61 has been introduced into the claw, these projections 67 precisely allow it to be held back and blocked in its final position taking advantage of the sharp angles 57 of the claw 41. At its introduction in the claw, the clip has the effect of spreading the two parts 51, 52, and by this action to keep this claw firmly in place in the ejection board 10. In addition to being very solid, this means of attachment is mainly the advantage of taking no place on the surface of the ejection board. he also has the advantage of being very simple, therefore cheap, and able to be easily and very quickly put in place without calling on any other complementary element.

Finally, we will mention that all the organs 11, 21, 41, 61 are preferably made by laser cutting but could also be be obtained by another cheaper method such as stamping by example. All these organs are preferably made of metal, steel or aluminum for example, but without it being a need. The profile of these organs is of rectangular section but could be different in order to decrease the mass of these organs while maintaining sufficient resistance bending. Advantageously, the thickness of the organ of the present invention is such that it occupies only a very small area on the board ejection, multiplying the possibilities of being able to position it between two even ajours very close together. Moreover, thanks to its low manufacturing cost, the body of the present invention may constitute a disposable element requiring no disassembly for reuse on another board ejection. Finally, we will also mention that the fastening system of the claw by the use of a clip could also be integrated into the fastening heads 14 and 24 to secure the bearing bars 11 and the reinforcement bars 21 against the ejection board 10.

Many improvements can be made to the purpose of the present invention within the scope of the claims.

Claims (6)

1. Device (11, 21, 41) for supporting, fixing and reinforcing a flat perforated tool (10) used in a waste stripping station in a cutting press, allowing its permanent fixing against one surface of the flat tool (10), characterized in that it is in the form of a laminate with an upper edge (19, 29, 49), a lower edge (20, 30, 50) and at least one end (18, 28, 48) constituting a gripping means, in that it comprises a number of fixing heads (14, 24, 44) which project from the upper edge (19, 29, 49) and are adapted to be inserted without clearance into apertures (6) formed for this purpose in the flat tool (10) and in that the fixing heads (14, 24, 44) are vertically split into two parts (46a, 46b) by an opening (43, 42) for blocking by a clip (61) which slides and engages therein in definitive manner and hold the said parts (46a, 46b) away from one another, so that the said fixing is achieved without use of any mechanical part connected to its edges, such as rivets, or screws and bolts and without any adhesive substance or component.
2. Device (11, 21, 41) according to claim 1, characterized in that it comprises openings (31, 32, 33) at which it can be divided into pieces.
3. Device (21) according to claim 2, characterized in that it comprises horizontal oblong openings (31) formed at the base of the fixing heads (24) just below the edge (29), and vertical oblong openings (32) formed between the fixing heads (24).
4. Device (21) according to claim 3, characterized in that the fixing heads (24) and the vertical oblong openings (32) are regularly spaced.
5. Device (11, 21, 41) according to claim 2, characterized in that the laminated profile has a rectangular vertical cross-section.
6. Device (11, 21, 41) according to claim 5, characterized in that it is made of a metal material.

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