Positioning and blocking device for tool carrier in a cutting apparatus.

The present invention relates to a device for centering and locking a tool-supporting frame in a cutting press, in particular a punching press for the working of paper or cardboard.

The cutting presses known to date, for the work of paper or cardboard to make cuts of folding cartons, are generally composed of several work stations arranged one after another, these stations work is commonly referred to in the order of their arrangement in the press, by feeding station or introduction, cutting station, stripping station and finally receiving station.

In this kind of machines, the paper or cardboard is generally in the form of substantially rectangular sheets. These sheets are taken from the top of a stack placed in the feeding station to be brought up to transport the conducting members through the cutting stations, ejection and reception.

In one of these blanking presses, the cutting station generally comprises a upper table or top rail fixed between two side frames and a lower beam or vertically movable lower platen. The cutting tool, which is in the form of a plate provided with threads cutters and feeding pumps, is fixed against the lower part of the upper beam so that, during the vertical movement upwards of the lower movable beam, the cutting the sheet of paper or board is made. It goes without saying that can be cut, at one time, a large number of box blanks are distributed over the surface of a sheet. By configuring the box blanks, there is always between small they waste it is necessary to remove to get to the receiving station, a semi-finished product in the form of a composite sheet a plurality of box blanks interconnected by small attachment points which must then be broken to separate each blank from one another.

Small waste which we have spoken are removed from the sheet in the stripping station which normally comprises an upper tool and a lower tool between which is mounted a perforated board whose openings are arranged exactly opposite the waste to be ejected. These openings over the same geometric shape as the shape of waste. The upper tools and lower perforated board are driven in a vertical movement from bottom to top and top to bottom synchronized with the sheets into the machine. The upper ejection tool is composed of a rectangular frame on which are mounted the ejection members are generally in the form of telescopic stripping pins. These ejection needles can be fixed adjustably on crosspieces connecting the lateral or longitudinal bars of the rectangular frame so that it can position the waste to eject and places it opposite the telescopic needles mounted on lower ejection tool. In another version, the upper ejection tool can be in the form of a wooden board in which it was planted at selected locations, non-telescopic hands while the lower ejection tool comprises about his telescopic needles placed in the needles of the upper ejection tool.

As is clear from what we have just described, the waste is pinched between the needles of the upper and lower tools and pushed down through the openings in the perforated board during the vertical movement of the ejection members. Such stripping station is described in more detail in US Patent 3,786,731.

The punch press can of course perform different tasks corresponding to several kinds and cuts of formats, it should adjust the position of the ejection tools according to each job and of course change the perforated board to adapt one that matches to work to achieve. Generally, each of the different tools or cutting or ejection, are centered along the median axis of the machine and with respect to a reference located on this central axis in the front part of each tool in such a way that their relationship tracking is ensured with maximum precision and ensures the repeatability of positioning during extraction or mounting them in their respective stations. To facilitate these adjustments is provided able to remove the lower upper tools and the perforated board of the machine. This is done by laterally extracting these elements of the stripping station, as you would with a drawer. To do this, the upper, lower and the perforated board chacuns tools are inserted into scenes appointed in their cradles then centered and locked in their working position. It is very important that the centering of these tools occurs with great precision to ensure the accuracy of the relative position between the upper and lower needles and with the openings of the perforated board. In ejections stations known to date, the perforated plate and the upper and lower tools are centered by means of a first squab integral with one of the longitudinal bars of the tool-supporting frame and an integral second squab the other longitudinal bar of the framework. Locking the tool-carrier frame is further combined with the second centering squab. Adjusting the lateral position and the longitudinal position of the tool is also possible by acting on the centering pigeons. In summary, the centering of the tool is made in two points located substantially at half the length of the longitudinal rods of the tool-supporting frame. Locking the tool-supporting frame is effected by means of a hook, integral with the cradle, which is ensured by clamping by means of a hexagonal screw, on the end of the second centering squab.

Using this centering and locking device has several disadvantages. First, with only two centering points located on either side of the tool-supporting frame, it occurs when locking a frame deformation which is detrimental to the relative positioning accuracy between the upper and lower stripping tools and the perforated plate , which in the case of the ejection of very little waste is not permissible. A deformation of the tool-supporting frame can also be caused by the mounting of the support bars of the ejection needle and in this case, the fact of using only two centering points do not compensate this deformation. It is becoming evident that the rigidity of the frame, once centered and locked, will not be very good because of its retention by just two points. In addition, the misalignment between the upper and lower needles causes the tipping of waste to eject and therefore jams require stopping the machine. This deformation also influences the identification between the tools mounted in the other stations of the machine. It must then face the fact that the locking operation requires the use of a tool to block the hexagonal screws used to lock the tool holder frame.

In the area of ​​cardboard, the cutting press users are increasingly faced with varied work requiring multiple tool changes and their main concern lies in the drastic reduction of the time allocated to these operations so as to increase as much as possible the actual production time of their machines. Faults relating to the positioning accuracy of the various tools of the punch press is also a source of malfunction can cause paper jams, they must also be removed to increase the effective production of the machine.

The present invention aims to overcome the above drawbacks by providing the user with a centering and locking device tool holder frames which is accurate, safe and fast assembly and disassembly.

For this purpose, the device according to the invention complies with what is stated in claim 1.

The invention will be better understood by studying the description of an embodiment of a centering and locking device given by way of example with reference to the accompanying drawings in which:<ul><li>Figure 1 is a general schematic perspective view of an ejection station,</li><li>Figure 2 is a front view of an ejection station,</li><li>Figure 3 is a schematic perspective view of a frame upper tool holders,</li><li>Figure 4 is a schematic plan view of the perforated carrier plate frame,</li><li>Figure 5 is a profile view, partially in section, of a first locking member of a frame upper tool holders,</li><li>Figure 6 is a side view, in partial section, of a second locking member of a frame upper tool holders,</li><li>Figure 7 is a view on A of Figure 5,</li><li>Figure 8 is a view B of Figure 5,</li><li>Figure 9 is a view C of Figure 6,</li><li>FIG 10 is a view on D in Figure 6,</li><li>Figure 11 is a side view of a locking member of a perforated carrier plate frame and,</li><li>Figure 12 is a sectional view along XII-XII of Figure 11.</li></ul>

Figure 1 is a general schematic perspective view of an ejection station 1 of a press cut. This ejection station 2 comprises an upper tool having, in the example chosen, the form of a wooden board 3 provided with ejection pins 4. The upper tool 2 is held in a support frame higher 5 slidable in the manner of a drawer in grooves, not shown, fixed to an upper cradle 6, vertically movable under the effect of a device with levers 7 and pull tabs 8 and 9 (see Figure 2).

The ejection station 1 also comprises a lower tool 10 maintained in a lower support frame 11 can also slide in the manner of a drawer in grooves, not shown, attached to a lower cradle 12, vertically movable under the action of a lever arrangement 13 and pull tabs 14 and 15 (see Figure 2). Generally, the lower tool has several bars 16, of which only a few have been shown so as not to impair the clarity of the figure. A series of telescopic stripping pins 17 is mounted on the bars 16 opposite to the ejection needles 4 of the top tool 2. Finally, the stripping station 1 comprises a third element in the form of a perforated plate 18 mounted on a frame 19 may in turn also be extracted from the stripping station 1 in the manner of a drawer. The perforations of the plate 18 are made so as to take account of the waste form to eject and 4 and 17 ejection needles, arranged facing each other, clamp the waste and pushing through the perforations of the plate 18 when the cardboard sheet to work is stopped in the stripping station.

Figure 3 is a schematic perspective view of an upper tool-supporting frame 20 comprising a front bar 21 and rear bar 22 connected by two crossbars 23 and 24 so as to form a rigid frame. In addition, the front and rear bars 21 and 22 are braced by two crossbars 25 and 26. In the example, the sheet comes to work in the stripping station in the direction of the arrow 27 and the door frame -tools top 20 will be removed from this station, for example when changing tools, perpendicular to the direction of the arrow 27. this figure also shows schematically, centering and locking the frame tool holder 20. the front part of this frame 20, at the front bar 21 is equipped with a guide block 28 having a groove 29 in which engages a guide member 30 allowing part of traveling in the direction indicated by the double arrow 31. Also on the front part of frame 20, opposite the guide block 28, is a locking pin 32 having a groove 33 and a bore 34 in which the centering and locking squab 61 has s 'to hire. The rear frame 20 at the rear bar 22, has a further guide pin 35 with a groove 36 in which engages a guide member 37 allowing the displacement of the frame 20 in the direction of the double arrow 38. in contrast to this guide post 35, the rear frame 20 has a supporting member 39 which is simply constituted by the guide frame in the slide 85. this arrangement guides, centering and locking the frame 20 provides excellent rigidity of the frame 20 when the latter is locked in the machine.

It should be noted that the construction of lower tool-supporting frame is made according to the same principle, the only difference being that the guide posts 28 and 35 and the centering pin and lock 32 will be reversed so as to the grooves 29, 33 and 36 are turned down the tool-supporting frame.

Figure 4 is a schematic plan view of the holding frame stripping board 40. The ejection plate is constituted by a perforated plate 41, shown here without perforations corresponding to waste locations to be ejected. This perforated plate 41 is fixed on a frame 42 by means of fixing lugs 43 and screws 44 screwed in the brackets 45 attached to the support bars adjustable 46 bearing on the front crossbar 47 of the frame 40 and on a crossbar 48 , also adjustable, connecting the two longitudinal bars 49 and 50 which connect the front crossbar 47 at the rear crossbar 51 of the frame 40. the cross bar 47 back and rear 51 engage in grooves 52 and 53 integral with a movable cradle 54 actuated by a pivoting lever 55. This lever 55 pivots about a point of rotation 56 located in the vicinity of the rear transverse bar 51 under the effect of a control means which is not shown here. The movable cradle 54 is pivotally connected to the lever 55 by an adjustable centering member 57 and by a centering and locking device 58 which will be described in detail in connection with Figures 11 and 12.

Figure 5 is a profile view, partially in section, of a first locking and centering member 59 of an upper tool-supporting frame 20. This figure represents the front part of the tool-supporting frame 20 and in particular the front bar 21 when the latter is engaged in the slider 60 of the top cradle 6. the first locking member 59 and centering comprises a flexible shaft 62, attached to one of its ends, in a slotted block 63 to the with two screws 64. the split pin 63 is integral with the slide 60 of the upper bed 6. This flexible rod 62 passes through the upper part of the centering and locking squab 61 having a countersink having two inclined planes 65 and 66 in opposition, the inclined planes being shaped roof. The centering and locking squab 61 is mounted in a sleeve 74 fixed to an adjustment gib 75 provided at its one of the ends of an adjusting stud 76 receiving a threaded rod 77 through an anchor post 78 attached to the upper cradle 6. the nuts 79 mounted on the threaded rod 77 will thus adjust the desired position of the centering and locking squab 61 by moving the adjustment gib 75, the latter being guided in an elongated slot 80 into which a cylindrical pin 81. the other end of the flexible shaft is provided with a handle 67. in order to be maintained in a locking position and an unlocking position, the flexible rod 62 s engages in a bayonet bracket 68 whose shape is visible in Figure 7 which will be further described, the bracket bayonet 68 being fixed to adjustment gib 75. in the position shown in Figure 5, the frame holder upper die 20 is centered and locked position, ie that the conical portion of the centering and locking squab 61 is engaged in the bore 34, thereby preventing any lateral extraction of the tool-supporting frame 20. thereof is further maintained, in the part opposite the locking lug 32, by the guide member 30 which engages in the groove 29 of the guide post 28. the guide member 30 is constituted by a stud guide 69 having a nose 70 has two inclined planes 71 and 72 (see Figure 8) which will act in conjunction with the inclined flanks 82 and 83 of the groove 29 of the guide stud 28 (see also Figure 8) to ensure accurate guiding of the tool-supporting frame 20. the guide post 69 is fixed to the slide 60 of the upper bed 6 by means of two screws 73. to unlock part tool holder 20, it is sufficient to move the flexible shaft 62 in the bayonet bracket bayonet 68 until the centering and locking squab 61 comes to occupy the position 61a shown in phantom, so that the centering and locking squab is disengaged from its bore 34 and allows the extraction side of the frame tool holder 20.

Figure 6 is a side view, in partial section, of a second locking and centering member 84 of an upper tool-supporting frame 20. This figure shows the rear part of the frame tool holder 20 and in particular the rear bar 22 when the latter is engaged in the slider 85 of the top cradle 6. the second locking member 84 and centering comprises a flexible rod 86, fixed to one of its ends, in a slotted block 87 to the with two screws 88. the split pin 87 is integral with the slide 85 of the upper bed 6. This flexible rod 86 passes through the upper part of the centering and locking squab 89 having a countersink having two inclined planes 90 and 91 in opposition, the inclined planes being shaped roof. The centering and locking squab 89 is mounted in a sleeve 92 fixed to an adjustment gib 93 provided at one of its ends with an adjusting pin 94 receiving a threaded rod 95 through an anchoring pin 96 fixed to upper cradle 6. the nuts 97 mounted on the threaded rod 95 will thus adjust the desired position of the centering and locking squab 89 by moving the adjustment gib 93, the latter being guided in an elongated slot 98 into which a cylindrical pin 99. the other end of the flexible rod 86 is fitted with a handle 100. in order to be maintained in a locking position and an unlocking position, the flexible rod 86 engages in a bayonet bracket 101 whose shape is shown in Figure 9 which will be further described, the bracket bayonet 101 being fixed to the adjustment gib 93. in the position shown in Figure 6, the door frame -tools top 20 is centered and locked position, that is to say that the conical portion of the centering and locking squab 89 is engaged in the groove 36, thereby preventing any lateral extraction of the framework toolholder 20. it is further maintained at the part opposite the locking lug 35, by the bearing member 39 which acts against the inner faces of the slide 85 (see Figure 10). To unlock part tool holder 20, it is sufficient to move the flexible shaft 86 in the bayonet bracket bayonet 101 until the centering and locking squab 89 comes to occupy the position 89a shown in phantom , so that the centering and locking squab is disengaged from the groove 36 and allows the side extraction of the frame tool holder 20.

It is sufficient to laterally extract the tool carrier frame 20 of the machine move simultaneously, or even one after the other, the two flexible rods 62 and 86 in the positions 62a and 86a and the pull against itself. This approach simple and quick saves valuable time during the exchange of stripping tools.

As we mentioned earlier in the description, part toolholder lower ejection is performed in the same manner and used as a centering and locking device in three points. The construction is similar, it does not seem wise to describe in more detail as the description on the framework upper tool carrier 20 can easily be transposed to this achievement.

Figure 7 is a view on A of Figure 5 which shows how the frame tool holder 20 and the first locking member 59 and centering are arranged relative to the upper cradle 6. For the understanding of this figure, please refer to the reference signs used in the description of Figure 5.

Figure 8 is a view B of Figure 5 showing the manner in which the tool-supporting frame 20 and the guide member 30 are arranged relative to the upper cradle 6 and how the guide member 30 is connected to the cradle top via a plate 102. for the understanding of this figure, reference is also made to the reference signs used in the description of Figure 5.

Figure 9 is a view C of Figure 6 which shows how the frame tool holder 20 and the second locking member 84 and centering are arranged relative to the upper cradle 6. For the understanding of this figure, reference is made to the reference signs used in the description of Figure 6.

Figure 10 is a view according to D of Figure 6 showing the manner in which the tool-supporting frame 20 and the guide member 30 are arranged relative to the upper cradle 6 is made and how the support of the tool-supporting frame 20 in the upper cradle 6 through the slide 85. for the understanding of this figure, reference is also made to the reference signs used in the description of Figure 6.

Figure 11 is a side view of a centering and locking device 58 of a holding frame stripping board 40 in which is mounted a perforated plate 41 and FIG 12 is a sectional view along XII-XII of Figure 11.

As shown in these figures and also in Figure 4 described above, this holding frame stripping board has only one centering and locking device 58. The holding frame stripping board 40 is secured mobile cradle 54. a locking pin 104 is mounted against a portion 106 attached to a fastener 105 of the moveable support lug 54. in order to adjust the locking position of the holding frame stripping board 40, the locking pin 104 has a threaded rod 107 which engages in a bore against the portion 106. the position of the locking pin 104 may be adjusted by acting on the nuts 108 of the threaded rod 107 (see also Figure 12). The locking pin 104 includes a bore 109 into which engage the cylindrical portion of the latch 110. The latch 110 is mounted so as to be slidable in a sleeve 111 driven into a support 112 integral with the holding frame board of ejector 40. the bore which receives the sleeve 111 is stopped at one of its ends against which bears a spring 113 also guided in a bore 114 formed in the upper end of latch 110. the latch 110 is in further provided with a control rod 115, the cylindrical portion 116 engages in a bayonet 117 machined in the support 112. the control rod 115 is further provided with a handle 118 by means of which it is possible, against the action of the spring 113, move from a locked position, shown in Figure 12, to an unlocked position 119 shown in phantom in Figure 11.