Abstract:
The invention relates to a device for removing break-off pieces ( 12 ), especially waste parts, from a sheet of material containing blanks or similar flat pieces. An abutment device ( 20 ) which can move in a longitudinal direction is associated with a break-off tool ( 40, 42 ). The abutment device protrudes into a through opening ( 16 ). Even when said device is in a rest position it supports the break-off component or waste part of the sheet of material ( 10 ) in an approximately parallel position. When the waste part moves, its position can be modified by the break-off tool and brought into a specific angle of inclination in relation to the sheet of material, especially when the waste part is lowered.

Description:
BACKGROUND OF THE INVENTION 
   The invention concerns an apparatus for removing broken-out pieces, in particular waste potions, from a sheet of material containing blanks or the like flat portions, as set forth in the classifying portion of the independent claim. 
   EP 0 446 702 B1 to the present applicant discloses that automatic stamping machines for the production of blanks from sheets of card in the folding box industry have been provided for more than 30 years with breaking-out devices which are preferably arranged in a setting-up table outside the stamping machine. Such a breaking-out station is of particular importance in terms of manufacture as in the event of incorrect use it involves the highest proportion of the total setting-up time and a poorly set breaking-out station results in continual disturbances in the production procedure. 
   In the breaking-out station the stamped cardboard sheet, after reaching a predetermined detent position, on the breaking-out surface which is usually provided by a breaking-out board or a female die, is freed of the waste by means of breaking-out pins or cutting edges which press from above. 
   Development in the breaking-out procedures involved firstly entailed the top tool pin which presses downwardly from above and which passes the waste portion through the opening in the breaking-out board. There was then added an additional bottom tool with bottom pins, which are aligned with the top tool pins and which clampingly hold the waste portion. As a breaking-out tool can reliably break out a waste portion only when there is a certain force-locking engagement between the tool and the waste portion, the above-mentioned bottom pins have proven to be an advantageous resistance at the moment when the breaking-out tool or breaking-out member comes to bear against the waste portion. 
   If there is a wish to avoid using a clamping tool, the breaking-out opening in the breaking-out surface must be smaller at various locations, than the waste portion which is associated therewith, so that the waste portion rests with a relatively high friction, in small surface areas, on the breaking-out surface or female die. When the breaking-out pin comes into contact with the waste portion, the above-mentioned resistance occurs by virtue of the friction which is then produced. When the breaking-out pin and the waste portion pass through the opening, friction occurs at the relatively close walls of the hole, whereby a certain force-locking action is achieved. 
   DE-A-25 35 452 discloses the so-called DYN-pin, namely a breaking-out pin having a tip or point whose substantially conical side walls are of contours which are concave in cross-section, with a smooth surface. In the breaking-out procedure, that tip bears against the waste portion which, by virtue of being supported on the edges of the opening, opposes the tip with such a level of resistance that the tip can penetrate slightly into the material of the waste portion. That prevents unwanted lateral deflection movement of the waste portion. As it passes through the opening, the waste portion bends, and the stressing force between it and the wall of the opening is intended to afford the DYN-pin sufficient friction for the desired force-locking engagement with the waste portion; that could then possibly make a bottom tool in itself unnecessary, when using the DYN-pin. 
   As a simplification for breaking-out tools, above-mentioned EP 0 446 702 B1 proposes a support means which is a surface which is movable and/or resilient within the opening—at least in part in an inclined position —at a spacing relative to the breaking-out surface and which, in its rest position, engages substantially parallel beneath the waste portion in the sheet of material and which, upon movement—that is to say primarily upon downward movement—of the waste portion, is transferred, by the breaking-out member, into an angle of inclination with respect to the sheet of material. The resilient surface can be in the form of a tongue-like spring which is fixed at one end to the breaking-out surface—substantially aligned therewith in the rest position—while the free end of the tongue-like spring is arranged in the opening. Also described are angle portions having one limb aligned with the breaking-out surface while the other limb thereof is pivotably mounted beneath the breaking-out surface and is subjected to a spring loading. The resilient surface can also be afforded by rubber profile members or by bristles. 
   Finally, DE-C-41 24 089 provides a cuboidal breaking-out tool of rectangular cross-section, from the pressing end of which two pressing tips or points project, in line with the two narrow sides thereof. 
   SUMMARY OF THE INVENTION 
   In consideration of that state of the art relating to the breaking-out procedure, the inventor set himself the aim of substantially improving the removal of waste portions from sheets of material and simplifying the tools required for that purpose. In particular the invention seeks to provide that those tools can be used for the treatment of very small waste pieces. 
   That object is attained by the teaching of the independent claim; the appendant claims set forth advantageous developments. In addition the scope of the invention embraces all combinations of at least two of the features disclosed in the description, the drawings and/or the claims. 
   In accordance with the invention, the support means is formed by a support tool which is rigidly connected in positively locking relationship to the breaking-out surface or female die in the edge region of the opening, and is provided with a contact or support surface which can be inclined with respect to that connection pairing. 
   In a preferred embodiment this connection pairing comprises a vertical receiving groove—extending in the breaking-out direction—in the female die at the edge of the opening thereof on the one hand and a coupling bar or rib which can be fitted thereinto, on the other hand. In a further preferred embodiment the support tool has an undercut groove for receiving a corresponding coupling bar of the female die. 
   The respective cross-sections of the coupling bar and the receiving groove should advantageously be of a dovetail-shaped configuration and thus define an operative position which is easy to bring about. It is perhaps possible to provide a plurality of such connecting pairings. 
   In accordance with a further feature of the invention the support tool is an angle portion with at least one coupling rib of dovetail-shaped cross-section which is formed out of the one limb—being vertical in the position of installation—, and another flexible limb which forms the support surface—being horizontal in the position of installation. In that respect, it has proven to be desirable for the angle portion generally to be formed from a material of limited flexibility, which ensures a long service life. 
   In a preferred embodiment the connection pairing comprises at least one vertical receiving groove—extending in the breaking-out direction—in the female die at the edge of the opening thereof on the one hand, and a portion—which can be fitted thereinto—of a vertical limb of the support tool on the other hand. The respective cross-sections of the coupling bar and the opening are advantageously to be of a rectangular configuration and thus define an operative position which is easy to bring about. A plurality of such connection pairings can possibly be provided. 
   It has proven to be desirable if the flexible limb forming the support surface has an edge opening which is delimited at both sides by cantilever portions, and, at a spacing relative to the edge opening, at least one inner opening. That configuration affords a particularly desirable support surface which is stable in respect of shape and nonetheless flexible. 
   It is also in accordance with the invention that formed on the vertical limb is at least one pin-like plug-in element which extends or extend at a spacing relative to the vertical limb and which is respectively adapted to be inserted into an opening provided in the female die at a spacing relative to the receiving groove. Like also the opening which receives the plug-in element, the plug-in element is to be of a rectangular cross-section, while the plug-in element projects either at a spacing relative to the back surface of the vertical limb or at a spacing relative to the flank surface of the vertical limb, from a respective transverse web portion. In the structure involving association with the flank surfaces, a pair of plug-in elements is preferred. 
   In a particular embodiment the flank surfaces of the vertical groove are stepped, wherein the vertical limb is supported in the back region, which is narrower in cross-section, of that stepped vertical groove, and therefore the horizontal limb projects beyond the wider front region of the vertical groove. 
   In another embodiment the vertical limb is to be connected with a coupling pairing to a limb, which extends in the vertical groove, of an angle bracket whose other limb is connected to the female die, preferably by means of force-locking engagement. It is however also possible to provide a pocket at the underside of the female die, for the limb of the angle bracket, whereby that limb projects in positively locking engagement into same. 
   So that the broken-out piece is possibly held after the releasing procedure, at least one catch finger can be arranged downstream, in the breaking-out direction, of the limb forming the support surface; a pair of catch fingers which are in flanking relationship on both sides is however preferred. The catch fingers increase in width from their free end towards the limb formed thereon, in terms of longitudinal section, for the purposes of increasing the degree of flexibility thereof. In another embodiment the horizontal limb is flanked by side portions which are formed on the other limb, and therefore extend vertically. 
   Another embodiment provides a support tool with a partial frame which is approximately U-shaped in cross-section and which comprises a back portion having the coupling rib and having two parallel side walls; a support plate for the broken-out portion is arranged between said side walls, pivotably about an axis which is generally horizontal in the position of use. 
   The feature whereby the breaking-out tools extend between surfaces of the support means, said surfaces being movable in the breaking-out direction, results in a higher level of operational reliability as the arrangement affords a kind of tongs or pincer engagement; that cannot be achieved in the state of the art as the breaking-out tools are usually within the contour which is defined by the free edges of the surfaces. 
   Engagement of the breaking-out tools can also become more efficient when an edge opening is disposed in opposite relationship to the free end of the tools, the edge opening extending from the free edge of the support surface. 
   It has proven to be desirable to associate with the support surface, as a breaking-out tool, a pressure pin having a rounded free end or a fork member with one or more finger-like fork prongs, preferably of flat cross-section. 
   In particular small waste pieces also take part in the bending movement of the breaking-out tool, in such a way that they assume a perpendicular position. When dealing with smooth cardboard surfaces, that results in slipping movement of the pressure pins on the surface of the cardboard and thus results in the waste portions being unsatisfactorily broken away. Therefore, for the sake of better engagement, the free end of the pressure pin or the fork prongs is in the form of a rough surface. That rough surface can be formed by a coating which for example is formed with oxides, carbides, corundum or the like and is possibly applied by means of thermal spraying. Another embodiment according to the invention provides a rough surface with irregularities such as teeth or steps in the surface of the pressure pin or the fork prong or prongs. The irregularities can be produced by a mechanical, chemical or electrical treatment. 
   By virtue of the rough surface described—for which protection is claimed separately—the arrangement affords the desired firm engagement and the piece which is to be broken away is effectively prevented from sliding away. For that purpose, it has been found sufficient for the axial height of the rough surface to correspond at most to the diameter of the pressure pin or the width of the fork prong, preferably making it less than 5 mm. 
   Each fork member is to project from a plate-shaped male die and in accordance with the invention it is connected thereto by a portion of the fork member which has clamping noses and which can also have abutments which are guided against the underneath surface of the male die. 
   Other insert portions for the female die are shaped support portions which are arranged in the opening of the female die at the edge thereof and which are fitted to plug-in profile members and which are disposed in mutually opposite relationship and which are provided with mutually directed radial support lips of elastic material. Preferably that shaped support portion is an angle portion of which one limb is the support lip, while the other limb formed thereon is formed by a hollow profile member; the latter preferably corresponds to a cylindrical cup and is pressed on to a plug-in profile member by a simple assembly procedure in the breaking-out direction. 
   The scope of the invention also embraces clip-like tools which are fixed at the opening in the female die and which each include a respective frame portion from which resilient support tongues project inwardly or on which are arranged inwardly disposed support plates which can be guided about a pivot axis; that arrangement therefore affords simple additional tools in the form of spring clips or mechanically moved clips which would even permit standardisation of the tools. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further advantages, features and details of the invention will be apparent from the description hereinafter of preferred embodiments and with reference to the drawings in which: 
       FIG. 1  is a plan view of a support tool for a waste portion for the removal thereof from cardboard sheets in the corrugated cardboard and folding box industry, 
       FIG. 2  is a side view of  FIG. 1 , 
       FIG. 3  is a side view corresponding to  FIG. 2  of another embodiment, 
       FIGS. 4 through 7  are diagrammatically illustrated successive method steps with a breaking-out board which is shown in section and which includes a support tool as shown in  FIGS. 1 and 3  and with which a breaking-out tool is associated, 
       FIG. 8  is a view on an enlarged scale approximately corresponding to  FIG. 6 , with a support tool which is modified in relation to  FIG. 6 , and another breaking-out tool, 
       FIG. 9  is a plan view of a part of a further breaking-out board with support tool and breaking-out tool as shown in  FIG. 8 , 
       FIG. 10  is a view corresponding to  FIG. 9  of a further embodiment, 
       FIG. 11  is a perspective view of a further support tool with breaking-out tool and the indicated end positions of a movable support plate, 
       FIG. 12  is a view corresponding to  FIG. 11  of an arrangement with a breaking-out tool, 
       FIG. 13  is a diagrammatic view in section relating to  FIGS. 11 and 12 , 
       FIGS. 14 and 15  respectively show a support tool in plan and a breaking-out tool illustrated in section, 
       FIG. 16  is a front view in section of the arrangement shown in  FIG. 9 , 
       FIG. 17  shows the mounting arrangement for the breaking-out tool of  FIG. 16  taken along line XVII—XVII therein, 
       FIG. 18  is a front view of a plate-like breaking-out tool in two embodiments, 
       FIG. 19  shows two side views in relation to  FIG. 18 , 
       FIG. 20  is a view in section on an enlarged scale through a further embodiment of the breaking-out tool of  FIG. 18 , 
       FIG. 21  is a view corresponding to  FIG. 18  of a further breaking-out tool, 
       FIG. 22  is a side view relating to  FIG. 21 , 
       FIG. 23  is a front view of another breaking-out tool, 
       FIGS. 24 through 26  show side views of three other embodiments of the breaking-out tool, 
       FIGS. 27 and 28  show the breaking-out tool of  FIG. 24  in two stages of a breaking-out operation, 
       FIGS. 29 and 30  respectively show a perspective view of a unit comprising a support tool and a breaking-out tool, 
       FIG. 31  shows a perspective view of another breaking-out tool, 
       FIG. 32  shows a perspective view of another embodiment of a support tool, 
       FIGS. 33 and 34  show two views corresponding to  FIGS. 4 and 5  respectively of a working operation with support tools as shown in  FIG. 32 , 
       FIGS. 35 through 38  show plan views of special tools having a spring action, 
       FIGS. 39 and 40  show plan views of special tools having a mechanical action, 
       FIGS. 41 ,  43  and  46  show sectional views of breaking-out boards with respectively inserted support tools, 
       FIGS. 42 ,  44  and  45  show plan views of the structures shown in  FIGS. 41 ,  43  and  46 , 
       FIG. 47  is a front view of the support tool of  FIGS. 43 and 44 , and 
       FIG. 48  is a perspective view of the support tool of  FIGS. 46 and 47 . 
   

   DESCRIPTION OF PREFERRED EMBODIMENTS 
   Cardboard sheets  10  which are used in the folding box industry have stamped blanks for folding boxes or the like, with waste portions  12  being produced in or on the blanks. Downstream of a stamping station which is not shown in the drawing for reasons of enhanced clarity thereof, the stamped cardboard sheet  10  passes on to a breaking-out board or a female die  14  of a thickness b for example of 12 mm, on which the sheet  10  is freed of its waste portions  12 ; the waste portions  12  are disposed over openings  16  which are of a configuration designed in dependence on the contour of the waste portions  12  and at which, in the cross-sectional view in  FIGS. 4 through 7 , an upper frame portion  17  with a vertical wall is followed by a downwardly opening conical portion  18 . 
   Fixed in the opening  16  is a support tool  20  for the waste portion  12 , which as shown in  FIGS. 1 and 2  is a kind of angle portion having two limbs  22  and  24  of flexible plastic material with a high level of endurance in relation to fluctuating loadings thereon. Projecting from the limb  22  which extends vertically in the position of installation is a coupling rib  27  which has flanks  26  of an undercut configuration and which is inserted into a vertical groove  28  of dovetail-shaped cross-section in the female die  14 . As  FIG. 9  clearly shows the vertical groove  28  extends from a wall surface  15  defining the opening  16 . 
   The resilient horizontal limb  24  of the support tool  20 , of a thickness a, has an inner opening  30  and at its free edge  25  an edge opening or recess  32 ; two prong-like cantilever portions  34  of the horizontal limb  24 , which flank the edge opening  32 , are curved in longitudinal section and each form a kind of bowl or cup. 
   In the embodiment shown in  FIG. 3 , formed on the vertical limb  22  is a catch finger  38  for the waste portion  12 . The catch finger  38  is curved downwardly in its longitudinal section and narrows towards its free end  36 . 
   The waste portion  12  which rests on the surface  25  of the horizontal limb  24  is subjected to a pressure from above by a breaking-out member or tool in the form of a pressure pin  40  with a roughened part-spherical pressure end which is similar to a fingertip, with the contact between the pressure end and the waste portion being in point form or—for example in FIGS.  8  and  12 —as a fork member  41 , in substantially linear configuration; the flat fork prongs  42  of the fork member  41  are aligned with each other. Both the part-spherical pressure end of the pressure pin  40  and also the flat ends of the above-mentioned fork prongs  42  are provided with a coating  44 , affording the roughness thereof, of an axial height h of between about 4 and 10 mm. The coating was produced for example by thermal spraying from aluminum oxide, corundum, carbide grains or the like. 
   The preferred height h is at most equal to the diameter d of the pressure pin  40  and the roughness depth is less than 0.5 mm. That coating can also be replaced by roughening of the surface of the pressure pin or the flat prong  41 , which is effected chemically, electrically or—for example by means of sand blasting—mechanically. 
   In the downward movement of the breaking-out tool or tools  40 ,  41 , the waste portion  12  is separated by pressure from the cardboard sheet  10  and carried away downwardly in the breaking-out direction x. 
   In the embodiment shown in  FIG. 9  the edge opening  32  is at its end of a part-circular contour and the horizontal limb  24  is flanked by side portions which respectively form the above-described catch fingers  38  and which—like also the horizontal limb  24  itself—are formed on the vertical limb  22 . 
     FIG. 10  indicates a connection pairing between the support tool  20   n  and the female die  14 , which is modified in relation to the embodiment shown in  FIG. 9 ; the female die  14  engages with a vertical bar  29  which projects from the wall surface  15 , into a vertical groove  31  in the support tool  20  or the vertical limb  22  thereof. The flank of the vertical groove  31  is identified by reference  26   a . 
   In the support tool  20   a  shown in  FIGS. 11 and 12 , the support surface  25  for the waste portion  12  is provided by a support plate  46  which hangs separately between side walls  23 ; the support plate  46  rests with lateral trunnions which are not visible—pivot axis A—in finite mounting grooves  48  in the side walls  23  and can be moved from the horizontal position into the inclined position indicated at  46   n . In that position the support plate  46  is disposed in approximately parallel relationship with the inclined front ribs  50  of the side walls  23 , the front ribs  50  also forming catch fingers. 
     FIG. 13  is intended to show the manner of suspending the support plate  46  forming a kind of mechanical finger, as well as forwardly and downwardly inclined front surfaces  52  of the side walls  23 , as deflector means for the waste portion  12 . 
   The support plate  46   a  in  FIG. 14 , which is intended for long waste portions  12 , shows two edge openings or chambers  32 , with which there are associated flat prongs  42  of a fork member  41  which is otherwise not shown herein. 
   In  FIG. 15 , strip-like cantilever portions  34   a  of flexible material project from oppositely disposed wall surfaces  15  which define the opening  16 . The cantilever portions  34   a  form between them chamber spaces  33  of a width as indicated at n; the cantilever portions  34   a  flank the pressure pins  40  which engage into the chamber spaces  33 , or flat prongs  42  corresponding to the pressure pins. 
     FIGS. 16 and 17  show that the fork member  41  is firmly driven into a male die  56  of plywood of a thickness b 1  of for example 12 mm, as far as abutments  54  which are formed from the fork member  41  and which are directed transversely with respect to the prong axis B. The firm fit is produced by means of abutment plates  59  ( FIGS. 21 through 23 ) which are near the upper edge and which are parallel to the prong axis B, or by means of clamping noses  60  or gripping ridges which project at both sides from the surfaces  58  of the fork member  41 . 
   The ridge-like clamping nose  60  or the abutment  54  respectively can also be seen in the fork member  41   a  shown in  FIGS. 18 through 25 . The free ends of the fork prongs or flat prongs  42 —the free ends being defined by straight or curved end edges  43  and  43   a  respectively—have in this case mechanically produced roughness in the form of teeth  61  which are inclined at about 30° in  FIGS. 18 and 19  and which are shaped near the edge at one or both sides, teeth  61   a  which project at about 90° in  FIGS. 21 and 22 , hooks  61   b  ( FIG. 20 ) or shoulders  61   c  which are formed on fork prongs  42   a . 
   In addition  FIG. 23  shows a breaking-out tool  41   b  with only one flat prong  42   b  which is delimited downwardly by the above-mentioned end edge  43   a  which is curved in cross-section. 
   In that respect,  FIGS. 27 and 28  clearly show how a small waste portion  12  is engaged by the free end of the flat prongs  42   a  and laid into the shoulder  61   c , for perpendicular positioning thereof. Reliable downward guidance of the waste portion  12  is ensured by virtue of the fact that it is pressed in force-locking engagement against the breaking-out tool or fork member  41   a  by the cantilever portion  34  of the support tool  20 . Because the waste portion  12  is caused to bear against the breaking-out tool  41   a  in force-locking engagement therewith in that way, the shoulders  61 , produce their effect. In the breaking-out process the breaking-out tool  41   a  presses the waste portion  12  against the support tool  20 , clamps it in place and guides it positively downwardly. In that procedure the waste portion is disposed approximately perpendicularly. Upon further downward movement of the breaking-out tool, the waste portion  12  is pushed downwardly by the tooth  61 ,  61   a —or the hook  61   b  or the shoulder  61   c . The support tool  20  or the cantilever portion  34  thereof moves rapidly back into its initial position. 
   The described system affords advantages not only in relation to internal waste portions  12 , but also in relation to so-called edge waste; the procedure for breaking away edge waste is effected only with the above-described combination of the breaking-out tool  41   a  and the support tool  20 ; wooden die or support members are unnecessary. The risk which arises due to wooden die or support members which are necessarily disposed close to the breaking-out female die  14  no longer arises. A spacing of 4 mm between the breaking-out tool  41   a  and the outside contour of the breaking-out female die  14  affords sufficient tolerance and security. A movement in the severing operation, which corresponds to the pitching action, carries the edge waste positively away from the breaking-out female die  14 . As in the case of internal waste, in this case also the edge waste is disposed perpendicularly and is reliably guided downwardly by the thrust teeth  61 ,  61   a ,  61   b ,  61   c . 
     FIG. 29  shows an illustrative perspective view of a female die  14  which is made from plywood, with an angle portion  20  which serves as a support tool being releasably secured to the opening  16  thereof; disposed above the angle portion  20  is a fork member  41   a  with shoulders  61 , which are formed in its flat prongs  42   a . 
   The fork member  41   a  in  FIG. 30  shows the teeth  61  which project inclinedly from the flat prongs  42  into the intermediate spaces between the prongs, and a region of a coating  44  on the finger or end portions  45  of the flat prongs, which are shaped downwardly as pointed tips. 
   The breaking-out tool  41   b  in FIG.  31 —corresponding to that shown in FIG.  23 —is provided with a flat prong  42   a  which is here disposed laterally and which has a shoulder  61   c  at its end. 
   Referring to  FIGS. 33 and 34 , in an opening  16   a  of the same cross-section throughout, the female die  14   a  shown therein receives on both sides a shaped support portion  62  which is clearly illustrated in  FIG. 32  and which comprises a cylindrical inversion-action neck  63  and a radial support lip  64  which in turn has an edge opening  32 . The inversion-action neck  63  is connected to a plug-in profile member  65 . 
   The waste portion  12  which lies on the mutually facing support lips  64  is urged in the breaking-out direction against the support lips  64  by pin-like breaking-out tools  40  which are provided above the support lips  64 . In that case, the support lips  64  are elastically deformed and, when relieved of load, move quickly back into the initial position. In this case also, the breaking-out tools  40  are arranged in the region of the edge openings  32 . 
   The drawing shows in plan hereinafter some diagrammatic views of special tools, more specifically  FIGS. 35 and 36  showing spring clips  66 ,  66   a  for waste portions  12   a  and  12   b  respectively of round and half-round contour, while in addition  FIGS. 37 and 38  show spring clips  70  and  68  for waste  12   c  of an extended so-called Euro-hole or for cigarette waste  12   d .  FIGS. 39 and 40  show mechanical clips  72  and  72   a  respectively for round waste portions  12   a  and for rectangular waste portions  12 . 
   These special tools  66 ,  66   a ,  68 ,  70 ,  72 ,  72   a  —which are suitable as a basis for standardisation—each have a frame portion  76  from which project spring tongues  34   a  which are directed inwardly in  FIGS. 35 through 37 . The rectangular frame portions  76  of the clips  72 ,  74  in  FIGS. 39 ,  40  include support plates  46   b  which are possibly of a resilient nature and which are limitedly rotatable about a respective pivot axis A and into whose edge opening or openings  32  projects a respective pressure profile member  78 . 
     FIG. 41  shows a support tool  20   e  whose vertical limb  22  which is of rectangular cross-section is provided with a strip  80  which is parallel thereto at a spacing y, forming a channel; the two are connected by a transverse web portion  82  which is formed thereon at both sides. 
   The parallel strip  80  engages from below into a stamped-out opening  84 , which is of a cross-section corresponding to the parallel strip  80 , in the breaking-out board  14 . The stamped-out opening  84  is separated from the opening  16  of rectangular cross-section, by a board web portion  86  which is disposed in the above-mentioned channel. A vertical groove  28   a —also of rectangular cross-section—extends from the opening  16 , with stepped flank surfaces  88 . The vertical limb  22  of the support tool  20   f  in  FIGS. 43 through 45  is also carried in the back region  90  of a vertical groove  28   a . Plug-in strips  92  of L-shape in longitudinal section are formed at a spacing y, by virtue of the above-mentioned transverse web portions  82 , on the flanks of the vertical limb  22 . In the rest position shown in  FIGS. 43 and 44 , the strips  92  are fitted into corresponding flank holes  94  in the breaking-away board  14 —the latter are therefore in alignment with the back region  90  of the vertical groove  28   a . 
   A support arrangement  96  in the breaking-away board  14  in  FIGS. 46 and 47  comprises an angular plastic body  21  which is provided for the vertical groove  28   b , the plastic body having a short vertical limb  97  which has a downwardly open plug-in passage  92  for a plug-in tongue  99 , of rectangular cross-section, of the vertical limb  100  of an angle bracket  102 . Its limb  101  which is horizontal in  FIGS. 46 and 47  is fixed in force-locking engagement to the underneath surface  13  of the breaking-out board  14 .