EP1348524A1 - 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 subject of the present invention is a support member, attachment and reinforcement of a flat tool used in an ejection station waste from a cutting press used in the packaging industry especially.

The transformation of sheets of paper, cardboard or material plastic in order to obtain blanks of boxes, includes a suite of operations including the leaves, apprehended one by one at their edge frontal by a series of clamps mounted along a transverse bar in displacement, are taken to a cutting and delivery station then in an ejection station where the waste resulting from 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 shown flat in a developed form which, after folding and gluing, will form the expected packaging boxes. The outlines of these poses are cut by cutting threads in the platen press, while the lines folding of these poses are marked by delivery nets during the same operation. To prevent the sheet from falling apart after cutting, the cutting nets will have been previously cut in places corresponding to each join of adjacent cut sheet parts. Therefore, all the poses remain fragile held together by bridges of material, called attachment points, spared from cutting by nicks in the cutting nets.

Although the arrangement of the poses on the sheet is carried out from the in the most judicious way possible, it is generally not possible to avoid produce waste resulting from cutting. This waste consists of the periphery of the sheet and by the internal intermediate parts which 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 into a bin or onto a carpet discharge.

Such a station generally comprises a mobile upper tool in the vertical plane equipped with ejectors, a perforated ejection board on which leaves successively stop to be cleared of their waste, and generally a lower tool collaborating with the tool top to remove waste from the sheet. However, sometimes this lower tool is not not used; the waste is then ejected from the sheet only thanks to the upper tool ejectors which push them down. In that case, ejection is said to be "dynamic". At high speed, the ejection board is by against subject to strong vertical pressures because the waste, not being more pinched to be removed, must rest partially on the edges of the opening, intended for their ejection, in order to make them above all bend down to simultaneously break all the attachment points which connect to the sheet. Without this, some attachment points may not be broken, leaving the waste hanging through the openings of the board and an inevitable jam when the sheet is removed from the ejection station. The solution to pinch the waste between the upper tool and a lower tool therefore makes it possible to guarantee, at very high speed, perfect elimination of all waste from the sheet without any jamming.

In a format similar to that of the sheet, the upper tool is in the form of a perforated board or a frame provided with several bars on which ejection needles are mounted which detach the leaf scraps pushing them down through the openings of the ejection board. Sometimes the top tool also includes pressers, made for example by small foam cubes, which have simple effect of holding the poses of the sheet against the upper side of the ejection board. Lower tool includes ejection needles telescopic arranged opposite those of the upper tool. This provision precisely allows to pinch the waste and remove it from the sheet, through the ejection board, during each tool cycle movable upper moving down, before the sheet is then taken out of the ejection station by the clamp bar which always grips its front edge. Such an ejection station is illustrated and described in more detail in patent CH689974.

It is on the ejection board of such a station that the object of the present invention finds its use. The upper and lower tools as well that the ejection board are generally each arranged and fixed on a support frame that can be easily removed from the ejection station in the horizontal plane like a drawer. Intended to only support poses of the sheet while allowing the removal of waste, the ejection board does not rarely has straight edges but has edges irregular which reproduce the contours of the poses located on the periphery of the leaf. Therefore, the ejection board cannot be directly fixed in its supporting frame by its upstream and downstream, or lateral edges, but requires to be mounted on longitudinal metal crosspieces or bars of fixed and suitable lengths to be placed and maintained in the supporting frame by their ends. These loadbars generally have a rectangular section, the longest sides of which are oriented vertically to be able to benefit from greater flexural rigidity, and are fixed against the underside of the ejection board by screwed brackets, on the one hand against the sides of these bars, and on the other hand in the board in question. The Patent CH575294 illustrates this arrangement well in Figures 2 and 3. However, this embodiment has several disadvantages, namely that, for their fixing, these bars require a multitude of small spare parts (brackets and screws) which require drilling, adjustment and relatively long assembly times. In addition, this embodiment occupies, on the surface of the ejection board, a certain significant space necessary for fixing brackets. However, according to the shape of the poses of the boxes cut, the installation of these brackets can sometimes cause problems to the formist responsible for placing the supporting bars between the openings of the ejection board; which can of course never be obstructed, even partially.

The openings of the ejection board are a direct function of the form poses and their arrangement on the sheet. It frequently happens it is not possible to avoid producing relatively large wastes. Consequently, the ejection board will be all the more fragile as these waste has a large area or is plentiful. Therefore, it is not rare to also have to strengthen the flexural strength of this board by the addition of reinforcing bars fixed against its underside of the same as the bars that carry it. So that these bars of reinforcement, generally of the same section as the supporting bars, can have an effective action on the rigidity of the ejection board, it is as desirable as long as possible, up to the format of the board, avoiding as much as possible having to fragment them in several pieces. However, to still 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 allowing to avoid all the openings imposed by the sheet in the board ejection. This meticulous work makes the realization of the ejection board difficult and even more expensive. Each ejection board being specific to a specific work, it will also be necessary to carry out such craft work to each new ejection board. Given the large number of fasteners required per board, these parts will generally be recovered just like the fixing brackets. However, the dismantling of a ejection board only contributes to increase the cost of carrying out a job given.

To lower the costs of producing an ejection board, we has already thought about replacing the generally metallic support bars, as well than those of reinforcement, by bars or crosspieces of another material cheaper and can be glued like wood. However, being less solid than metal, this material in return required more dimensioning important for the thickness of the supporting sleepers and the sleepers enhancement. This oversizing had the disadvantage of occupying more space on the surface of the ejection board and therefore became even more difficult to dispose of such sleepers while avoiding all openings intended for the ejection of waste. The ends of the sleepers generally have a more tapered shape, machined so that that they can come into engagement with the fixing system provided on the frame carrier. The tapered profile of the ends of these crosspieces, when they are in wood, weakens the latter which become delicate and require pay particular attention when handling the ejection board. Finally, due to their rapid wear, workshop tests have also shown that such ejection boards quickly tended to be subject 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 plate, support, fixing and reinforcement members not having the aforementioned drawbacks. For this purpose, these bodies must be able to be manufactured simply, in a material having a great rigidity and which preferably inexpensive. From a uniform production and standardized, these organs must also be able to be almost ready to use without requiring any particular shaping, for example by folding of these. These organs must also be able to be fixed on the board ejection without any screws or additional elements, and this fixing must be solid, almost instantaneous and require no adhesive substance filler like glue which requires a certain drying time or requires special handling if it is quick setting for example. Finally, these organs must also be the solution sought for the realization of a ejection board in an extremely short time and at such a cost, no recovery is to be considered if no storage is planned for for future reuse for identical work.

These aims are achieved thanks to the present invention which has as its object a support, fixing and reinforcement member in accordance with what is stated 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 without any limitation being implied 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 out poses are drawn therein.
• Figure 2 is a bottom view of a perforated ejection board on which the sheet of Figure 1 comes to stop to be rid of its waste.
• Figure 3 is an elevational view of a supporting 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 supporting bar, or preferably a reinforcing bar used to stiffen the ejection board weakened by its openings.
• FIG. 5 shows the female part of another embodiment of the member of the present invention, used mainly as a gripping means to hold the ejection board in its carrying frame.
• FIG. 6 represents, on a portion of the crown, a plurality of male parts of the embodiment illustrated in FIG. 5, intended to be clipped into the female part to fix the latter to the ejection board in a simple manner and final.

Figure 1 shows the division of a leaf 1 into a multitude of poses 2 and of waste 3, which result from its cutting after the action of a platen press in a cutting station. On the example given by this figure, are represented, in their developed form, twelve poses 2 or blanks of cardboard box arranged side by side on sheet 1. In order to better distinguish each of these poses, they have been alternately represented by two different shades. The exterior features of each of these poses define the outline of the developed box, such that it has been cut, while the interior lines correspond to the lines that have been marked by the discharge nets during the cutting. To be able to go from the cutting station to the station waste ejection, the sheet 1 is driven at its front edge by a gripper bar 4 moving in the direction of arrow 5.

Figure 2 shows, in a bottom view, the planar tool of the ejection station, consisting of an ejection board 10 whose geometry corresponds to the arrangement of poses 2 on sheet 1. In correspondence with this ejection board is also shown on this same figure, sheet 1 as cut according to the contours of each pose 2. The periphery of this sheet as well as the lines of cutting of the poses are illustrated by dashed 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 the openings 13 made in the board. From this done, all waste 3 from sheet 1 is either above the spaces openwork of the ejection board 10, or outside of it for the waste located at the edge of the sheet. 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 a single operation, either through the board perforated, either in its periphery. Once this operation is completed, sheet 1 spring from the ejection station, in the direction given by arrow 5, without dislocate thanks to the different attachment points (too small to be illustrated) which still connect all the poses 2 together.

Against one of the surfaces of the ejection board 10, usually against its lower surface are fixed carrying bars 11 which have for double purpose of supporting the ejection board when it is inserted in machine in the ejection station and offer a gripping means allowing to grip and rigidly fix this board in the station ejection, usually via a horizontal support frame can be slid in the machine like a drawer. The ejection station and the supporting frame have not been deliberately shown in the figures attached, since they do not directly concern the subject of this invention and do not provide any additional elements necessary to understand how it works.

Between the two upper bearing bars, illustrated as an example Figure 2 also shows a few bars of reinforcement 21 which make it possible to restore a certain rigidity to the board openwork ejection 10. The supporting bars 11 and the reinforcing bars 21 are precisely part of the object of the present invention and will be described in detail in the following study.

Figure 3 is an elevational view of a supporting bar 11, according to the invention, fixed against the lower surface of the ejection board 10 shown here in vertical section. This supporting bar 11 has a flat laminated geometry defining an upper edge 19 and an edge lower 20. In order to be able to fix without play in the ejection board without the addition of any mechanical part attached to it, without the addition of rivets or hardware and without the addition of a substance or of an adhesive element, this supporting bar 11 is provided, along its edge upper 19, of a plurality of fixing heads 14 each having a shape reminiscent of the tip of a hook. Each fixing head 14 has therefore a trunk 15 surmounted by a terminal portion 16 having at least one projection 17, preferably two, relative to the vertical edges of the trunk 15. The latter have a length such that the end portion 16 is located preferably completely embedded in the thickness of the ejection board once the supporting bar 11 has been correctly inserted. As shown 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, rectangular or even triangular shape for example.

So that the load-bearing bar can be inserted into the board ejection 10 without damaging the latter, openings 6 have been previously provided in this plate, in line with the locations of the fixing heads 14. These openings can be made by means of a laser machining at the same time as, by the same means, the openings 13 made in the ejection board. The latter being usually wood, laser machining is no problem particular and brings the advantage of being fast, precise and completely usable common 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 supporting bars 11 on the ejection board 10, it suffices to apply pressure on these bars, in striking for example the lower edge 20 using a hammer or a mallet, until the upper edge 19 is completely pressed against the face bottom of the ejection board 10. Due to the shape of the projections 17, these these prevent any removal of the supporting bar which is then firmly anchored in this board. Preferably, it is expected that the upper surface of the fixing head comes slightly below the level of the upper face of the ejection board. However, it would 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 at least one of the ends 18 of this bar is profiled accordingly.

Figure 4 is a partial elevational view of another embodiment of production of a supporting bar 11 or, preferably as described below, a reinforcement bar 21 used to stiffen the ejection board weakened by its openings. This reinforcement bar also has a flat laminated geometry defining an upper edge 29 and an edge lower 30. In FIG. 4, only the reinforcing bar 21 is represented. For reasons 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 reinforcing bar 21 are identical to the fixing heads 14 of the supporting bar 11 and fill the same role. Therefore, each of these heads 24 also comprises a trunk 25 vertical, an end portion 26 and preferably two projections 27 arranged at the lower ends of the terminal part 26.

The main difference between the load-bearing bar 11 and the reinforcement bar 21 resides in the fact that the latter has horizontal oblong openings 31 and vertical openings 32, as well as openings grooved 33 machined at the base of each trunk 15 on each side of its two vertical edges. The horizontal oblong openings 31 are practiced at the base of the trunk 25, slightly below the level of the ridge upper 29.

Thanks to this horizontal oblong opening, it becomes possible to easily break the fixing heads 24 using a simple universal pliers. The position of this opening, slightly behind the level of the edge upper 29, as well as the vertical grooves provided by the grooves 33 of on either side of the trunk 25, ensure that the breakage of the head of fixing 24 will not interfere with the reinforcement bar against the face of the ejection board 10 when it is assembled.

The vertical oblong openings 32 also have the function of facilitate the sectioning of the reinforcement bar 21 in places determined. These regularly spaced openings are 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 have to segment a reinforcing bar into several elements in order to be able to arrange them between two supporting bars 11, for example, or between the openings 13 of the ejection board without these are not obstructed. Depending on the judicious location of such a bar reinforcement and according to the shape and the arrangement of the poses 2 on the sheet 1, the reinforcing bar portions can have variable lengths. Therefore, it is very advantageous to be able to easily cut a bar of reinforcement in elements of different lengths as required. Since the spacing of the fixing heads 24 is regular, invariable and known in advance, it is also easy to predict where the openings 6 allowing the passage of the fixing heads in the board ejection 10. These openings 6 can therefore be machined at the same time than those provided for the supporting bars 11 and therefore at the same time as complete machining of the entire ejection board.

In order to be able to use the reinforcement bars as well as load-bearing bars and conversely, the reinforcement bars 21 are also provided with at least one end 28 profiled in the same way as the corresponding ends 18 of the supporting bars 11. It also goes without saying that end section of a reinforcing bar can both be used for its reinforcing function and for its function as a means of gripping the ejection board in the fixing device provided to keep 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 load-bearing 11 over the entire length of the ejection board or to place them in sufficient number. It can also happen that even the smallest stretch end of a reinforcing bar 21 is still too long and cannot not be placed in a desired place on the ejection board to fill its gripping function. To overcome this possibility, a another embodiment of the organ of the present invention, composed of two interlocking parts which are illustrated by Figures 5 and 6.

FIG. 5 represents a claw 41 constituting the female part of this other fixing member used mainly as a gripping means to hold the ejection board. Claw 41 also has a flat laminated geometry defining an upper edge 49 and an edge lower 50. This claw consists of a slotted fixing head 44, or split, into two terminal parts 46a and 46b by a large and first opening 43 of trapezoidal shape. Leaving aside this opening trapezoidal 43, the fixing head 44 is quite similar to the heads of attachment 14 and 24 described above. Thus, each terminal part 26a, 26b respectively overcomes a portion of trunk 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 at its intention in the ejection board 10, as illustrated in Figure 5. Au right of this opening 6, this ejection board is supported on two small consoles 53 forming a seat for the claw when it is mounted in the ejection board.

The trapezoidal opening 43, dividing the fixing head 44 in two preferably symmetrical parts, leads to a second opening 42, formed 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 of its ends, at least, by a foot 48. This foot constitutes, just like the ends 18 and 28 of the bars described above, the gripping means interacting with the device for fixing the ejection board provided in the machine. Together, the 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 planned to insert a corner, or clip 61 shown in broken lines in the Figure 5, through the trapezoidal opening 43. For this purpose, Figure 6 shows a plurality of clips 61, arranged on a portion of crown 64, and each constituting the male part which must fit into the claw 41. Each of these clips is connected to the crown, or crown portion 64, by a thin bridge material 65 so that it can be easily detached manually.

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

Once the clip 61 has been introduced into the claw, these projections 67 precisely allow it to be retained and locked in its final position by resting on the sharp corners 57 of the claw 41. During its introduction in the claw, the clip has the effect of separating the two parts 51, 52, and by this action of keeping this claw firmly in place in the ejection board 10. In addition to being very solid, this fixing means presents above all the advantage of taking no place on the surface of the ejection board. he also has the advantage of being very simple, therefore inexpensive, and of being able to be easily and very quickly set up without using any other complementary element.

Finally, it will be mentioned that all the organs 11, 21, 41, 61 are preferably manufactured by laser cutting but could also be obtained by another cheaper process such as stamping by example. All these organs are preferably made of metal, steel or aluminum for example, but without this 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 to bending. Advantageously, the thickness of the member of the present invention is such that the latter occupies only a very small area on the board ejection, thus increasing the possibilities of being able to position it between two even very close together. In addition, thanks to its low manufacturing cost, the member of the present invention may constitute a disposable element which requiring no disassembly for reuse on another board ejection. Finally, we will also mention that the claw fixing system by the use of a clip could also be integrated in the fixing heads 14 and 24 to fix the supporting bars 11 and the reinforcing bars 21 against the ejection board 10.

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

Claims (9)

Organ (11, 21, 41) for supporting, fixing and reinforcing a perforated planar tool (10) used in a waste ejection station of a cutting press, characterized in that it comprises means (14, 24, 44, 15, 25, 45a, 45b, 16, 26, 46a, 46b, 17, 27, 47, 61) authorizing its permanent fixing against one of the faces of the planar tool (10) 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. Device (11, 21, 41) according to claim 1, characterized in that it has a laminated geometry defining an upper edge (19, 29, 49), a lower edge (20, 30, 50) and at least one end (18, 28, 48) constituting a gripping means. Device (11, 21, 41) according to claim 2, characterized in that it comprises a plurality of fixing heads (14, 24, 44), forming protruding parts with respect to the upper edge (19, 29, 49), intended to be inserted without play in openings (6) provided for this purpose in the planar tool (10). Device (11, 21, 41) according to claim 3, characterized in that the fixing heads (14, 24, 44) are split vertically into two parts (46a, 46b) by an opening (43, 42) intended to be obstructed by a clip (61) slipping there and hooking it definitively while maintaining said parts (46a, 46b) spaced from one another. Device (11, 21, 41) according to claim 3 or 4, characterized in that it comprises openings (31, 32, 33) making it possible to segment it in line with the latter. Device (21) according to claim 5, characterized in that it comprises horizontal oblong openings (31) formed at the base of the fixing heads (24) just below the edge (29), in that it comprises vertical oblong openings (32) formed between the fixing heads (24). Device (21) according to claim 6, characterized in that the fixing heads (24) and the vertical oblong openings (32) are regularly spaced. Body (11, 21, 41) according to claim 2, characterized in that said laminated profile has a rectangular vertical section. Device (11, 21, 41) according to claim 9, characterized in that it consists of a metallic material.

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