EP0200622A1 - Press tool provided with a guiding and ejecting system for the metal strip - Google Patents

Abstract

Press tool provided with a system for guiding and releasing the metal strip passing through the tool, characterized in that it comprises, in an execution of a successive manufacture of several parts of predetermined dimensions and different shapes , a system for guiding and releasing (14) the metal strip (7), provided with adjustable sliding means (15) and interchangeable means (16) which make it adjustable and adaptable both to certain preselected widths and to degrees of brittleness of the metal strips used (7), in certain predetermined dimensions mined in height of the parts to be manufactured and in the various mechanical operations carried out by the tool in this strip (7).

Description

The present invention relates to a press tool provided with a metal strip guiding and releasing system.

For the manufacture of parts made of thin metal or metal sheet, tools are usually used which are mounted on presses to perform punching, stamping, bending, bending, etc. operations. These tools are frequently recovery and tools to follow. We usually call a recovery tool, a press tool that operates only once, on a sheet metal blank to give it a more or less complex shape. Operations such as punching, stamping, bending, cutting, etc ... in general can not all be done with a single recovery tool but they are done on a range of such tools. And we call tool to follow, in general, a tool comprising several aligned work stations, one arranged after the other, on which we scroll in a determined pitch, a strip of metal or sheet metal to achieve on this strip by each of these work stations, a predetermined operation such as punching, stamping, folding, cutting ... and obtaining at the exit of the last of these stations, a finished part, detached from this strip of metal or sheet metal, and having a more or less complex shape.

These tools generally include, as main component parts, working parts constituted by punches and dies, holding parts such as blank clamps, punch holders and die holders, fixing soles and systems for guiding strips of metal or sheet metal in their stepwise progression between these punches and dies.

According to a usual technique, each press tool is designed for a given part to be manufactured. As a result, there are as many tools as there are parts to manufacture. Indeed, for such a tool, any change in size and / or shape of a given part to be produced, entails a complete change of tool. There is thus a significant expenditure in raw material, labor and time.

According to another known technique, in a tool to follow the dies and punches are made removable and interchangeable so that several pieces of different dimensions and shapes can be successively produced following a change of dies and punches. However, such a tool works with a single metal strip width and manufactures parts included within limited dimensional limits both in width and in height. When parts of relatively small dimensions are produced with such a tool in the same metal strip intended for parts of relatively larger dimensions, wastage results in significant scrap metal. When such a tool is made to manufacture relatively flat parts, the tool is not able to produce parts subjected to folding and having relatively more bulky dimensions in height, because the metal strip not being lifted sufficiently at the - above the matrices, risk of being blocked in its scrolling or seriously distorted.

The present invention, aiming to avoid these drawbacks, makes it possible to produce an efficient, economical press tool provided with an improved system for guiding and releasing or lifting up a metal strip making the tool suitable for using metal strips with widths. different in a successive manufacture of several parts of different dimensions, to manufacture parts with different dimensions in height, and to obtain an appreciable saving in raw material, labor and time.

According to the invention, a press tool provided with a system for guiding and releasing a metal strip running through the tool between dies and punches is characterized in that it comprises in an economical execution of '' a successive manufacture of several pieces of predetermined dimensions and different shapes, a system for guiding and releasing the metal strip, provided with adjustable sliding and interchangeable changeable means making it effective, adjustable and adaptable both to certain preset widths and the degrees of fragility of the metal strips used, certain predetermined dimensions in height of the parts to be manufactured and the various mechanical operations carried out by the tool.

• -la figure 1 représente une vue schématique, incomplète, en coupe verticale d'un outil de presse selon l'invention muni de poinçons et matrices interchangeables ;
• -la figure 2 représente à une autre échelle, une vue en coupe verticale d'une partie d'un seul côté d'un système réglable et adaptable de guidage et de dégagement de bande de métal ou tôle, faisant partie de l'outil de la figure 1, montrant le système en position basse ;
• -la figure 3 représente à une autre échelle, une vue éclatée de la partie du système réglable et adaptable de guidage et de dégagement de bande de métal ou tôle, illustrée dans la figure 2, montrant les deux côtés de cette partie de ce système qui est muni d'une réglette transversale de guidage et de dégagement de la bande de métal ;
• -la figure 4 représente une vue éclatée de la partie du système illustrée dans la figure 2, vue analogue à celle de la figure 3 montrant ce système pourvu de bobines où galets à gorge à la place d'une réglette transversale ;
• -la figure 5 représente une vue éclatée de la partie du système illustrée dans la figure 2, vue analogue à celle de la figure 3, montrant ce système pourvu de deux réglettes longitudinales à la place d'une réglette transversale ;
• -la figure 6 représente à une autre échelle, une vue de dessus schématique de la semelle inférieure de fixation de l'outil de la figure 1, munie d'une matrice interchangeable et du système de guidage et de dégagement de bande de tôle illustré dans la figure 5, équipé uniquement de réglettes longitudinales ;
• -la figure 7 représente une vue de dessus - schématique de la semelle inférieure de fixation de l'outil de la figure 1, munie d'une matrice interchangeable et du système de guidage et de dégagement de bande de tôle illustré dans la figure 4, équipé uniquement de bobines ou galets à gorge ;
• -la figure 8 représente une vue de dessus - schématique de la semelle inférieure de fixation de l'outil de la figure 1, munie d'une matrice interchangeable et du système de guidage et de dégagement de bande de tôle illustré dans les figures 2 et 5, équipé de réglettes transversales, et
• -les figures 9, 10, 11 représentent à une autre échelle des vues, en perspective, de trois variantes de réalisation de cales ou butées à plusieurs épaisseurs pour le réglage de position haute déterminant la course du système de guidage et de dégagement ou relevage de bande de tôle partiellement illustré dans la figure 2.

To better understand the invention, a number of embodiments are described below illustrated by the accompanying drawings,

• FIG. 1 represents a schematic view, incomplete, in vertical section of a press tool according to the invention provided with interchangeable punches and dies;
• FIG. 2 represents, on another scale, a view in vertical section of a part on one side of an adjustable and adaptable system for guiding and releasing a strip of metal or sheet metal, forming part of the tool the Figure 1, showing the system in the down position;
• FIG. 3 represents on another scale, an exploded view of the part of the adjustable and adaptable system for guiding and releasing a strip of metal or sheet metal, illustrated in FIG. 2, showing the two sides of this part of this system which is provided with a transverse strip for guiding and releasing the metal strip;
• FIG. 4 represents an exploded view of the part of the system illustrated in FIG. 2, a view similar to that of FIG. 3 showing this system provided with coils or grooved rollers in place of a transverse strip;
• FIG. 5 represents an exploded view of the part of the system illustrated in FIG. 2, a view similar to that of FIG. 3, showing this system provided with two longitudinal strips in place of a transverse strip;
• FIG. 6 represents on another scale, a schematic top view of the lower sole for fixing the tool of FIG. 1, provided with an interchangeable matrix and with the guide and release system for the strip of sheet metal illustrated in Figure 5, equipped only with longitudinal strips;
• FIG. 7 represents a top view - schematic of the lower flange for fixing the tool of FIG. 1, provided with an interchangeable matrix and the system for guiding and releasing the sheet metal strip illustrated in FIG. 4, fitted with grooved rollers or rollers only;
• FIG. 8 represents a top view - schematic of the lower sole for fixing the tool of FIG. 1, provided with an interchangeable matrix and the system for guiding and releasing the sheet metal strip illustrated in FIGS. 2 and 5, equipped with transverse strips, and
• FIGS. 9, 10, 11 show, on another scale, perspective views of three alternative embodiments of shims or stops of several thicknesses for the adjustment of the high position determining the travel of the guidance and release or lifting system. sheet metal strip partially illustrated in Figure 2.

The present invention is applicable both to a recovery tool and to a tool to follow.

A press tool 1, according to an exemplary embodiment of the invention schematically illustrated in Figures 1, 6, 7, 8 is intended to be mounted on a press 2 whose table 3 and the slide 4 are shown schematically in broken lines .

The press tool 1 comprises a matrix 5 and a removable punch 6 respectively performing various mechanical operations such as punching, stamping, cutting ... in a metal strip or sheet metal 7 scrolled in a predetermined pitch, and giving at the outlet of tool 1, a finished part having a more or less complicated shape.

The removable matrix 5 and punch 6 are held respectively at the lower sole 8 and at the upper fixing sole 9 by die holders 10 and punch holder 11.

The metal strip or sheet metal 7 is firmly applied against the die 5 during the execution of the mechanical operations performed by the punch 6 and the die 5, by a blank holder 12 whose removable part 13 also serves as a sliding guide for this. punch 6 and means for releasing the metal strip or sheet 7 gripped by this punch 6.

According to an important characteristic, in the guide and release system 14 of the metal strip or sheet 7 in its travel through the tool 1 comprises adjustable sliding means 15 and interchangeable 16 (Figure 2) making this system adjustable in stroke of clearance of the metal strip 7 with respect to the matrix 5 in other words as a function of the overall height of the part to be manufactured and adaptable both to certain preset widths and to the degrees of fragility of metal strips used and the various mechanical operations carried out by the tool, causing these metal strips to be jammed or not at the level of this matrix 5. The guide and release system 14 is mounted on a lower fixing flange 8 of the tool 1 .

A good adjustment of the clearance height of the metal strip or sheet metal 7 vis-à-vis the die 5 allows this strip to move normally during the work of the tool 1 without being hindered by the presence of the part during training in this band and by that of this same matrix 5. A good adaptation of the system 14 in means for releasing or lifting and guiding the metal strip or sheet metal 7 vis-à-vis the dies 5, makes it possible to avoid any untimely retention of this strip by jamming it at the level of these dies 5 , which leads to unacceptable deformations in this metal strip 7 and possibly a blocking of the movement of this strip or of the tool 1, and to avoid breaks of the metal strip 7 because of its degree of brittleness.

According to another characteristic, the guide and release or lifting system 14 of the metal strip or sheet metal 7 comprises on the one hand several vertically movable supports 15, with adjustable stroke determining their high position, located in the lower fixing flange 8 of the tool, regularly spaced along the path of the metal strip or sheet 7, outside the active areas of the die 5 and of the punch 6 - (FIGS. 6 to 8), diametrically opposed in pairs on the two longitudinal sides of this strip, and constantly resiliently recalled in their high position, and on the other hand a range of guides of choice, interchangeable and removable 16 which, intended to be mounted on the upper ends of these supports to serve as guide means and for releasing or lifting this metal strip or sheet metal 7 as it travels through the tool 1, make this system 14 adaptable both to certain preset widths of the metal strip or sheet metal 7 and the dimensions and shapes of the part to be manufactured, that is to say its size.

In an example illustrated in FIGS. 2 to 5, each of the supports 15 of the guidance and release or lifting system 14 comprises a fixed vertical sheath 17 implanted in the lower fixing flange 8 of the tool 1, a movable stud 18 of which the lower part slides vertically in the bore of the fixed sheath 17 and the upper part carries at its free end a guide 16 serving as a means of guiding and releasing or lifting the metal strip or sheet metal 7, and a spring system 20 , mounted between the bottom of the fixed sheath 17 and the lower part of the stud 18, tending to push this stud 18 axially and elastically towards the outside of this sheath 17.

In the example of FIG. 2, the movable stud 18 comprises in its lower part a blind axial hole 19 for housing part of the spring system 20 and in the end of its upper part a threaded hole 21 intended to receive a screw fixing 22 of a guide 16, the threaded hole 21 and the fixing screw 22 can be replaced by a shoulder hole and a ball pin of a known type not shown. The movable stud 18 further comprises in its surface two recesses, grooves or longitudinal flats 23 and 24, one 23 cooperating with a lug or stop 25 blocked by a radial notch 26 formed in the wall of the sheath 17 and fixed by a screw 27 to the lower fixing flange 8 of the tool 1 to prevent any rotation of the movable stud 18 around its axis during its sliding, while allowing its axial displacement, and the other 24 forming at its ends an upper shoulder 28 and a lower shoulder 29 which cooperates with a shim or projecting adjustment stop 30 whose upper and lower surfaces delimit its thickness, in order to determine with the shoulder the high position of the movable stud 18, that is to say the travel of movement of the movable stud 18 or of the support 15 in other words the stroke for releasing or lifting the metal strip or sheet 7 carried out by the guidance and release or lifting system 14. The shim or adjustment stop 30 is constituted by a e end of an S-piece fixed in a groove 31 of the lower fixing flange 8 of the tool 1 by a screw 32. The spring system 20 is preferably made up as shown in FIGS. 2 to 5, by two compression springs 33, 34 with a cylindrical part 35 axially interposed therebetween. A range of interchangeable and removable guides 16 of the guide and release or lifting system 14 comprises first of all interchangeable transverse strips 36 (FIGS. 2, 3 and 8) with several dimensions of guide inter-grooves 37, each corresponding to a predetermined width of metal strip or sheet 7 usable in tool 1; secondly, interchangeable longitudinal strips 38 with a longitudinal guide groove 39 (FIG. 5) and with several widths defining, respectively, in their mounting in pairs and opposite (FIGS. 6 and 8), several dimensions of guide grooves, each corresponding to a predetermined width of metal strip or sheet 7 usable in tool 1; thirdly, interchangeable coils or rollers 40 with guide grooves 41 (FIG. 4) with several diameters defining, respectively in their assembly in pairs and opposite (FIG. 7), several dimensions of guide grooves, each corresponding to a predetermined width of metal strip or sheet 7 usable in tool 1.

In the guidance and release or lifting system 14 mounted on the tool 1, the interchangeable and removable guides 16 are chosen from these transverse strips 36, longitudinal strips 38 and the coils or grooved rollers 40. This choice which can weigh on the right function The tool 1 is often a function of the data or working conditions of the tool 1, such as those relating to the fragility of the metal strip 7, to the configuration of the workpiece to various mechanical operations performed by the tool 1. For example when the metal strip or sheet 7 used is neither wide nor fragile and the parts to be manufactured are flat parts or curved parts, the coils or grooved rollers 40 are preferably mounted on supports 15 of the guidance and release or lifting system 14 as illustrated in FIG. 7. When the metal strip or sheet 7 is wide or the parts to be formed in this strip can be trapped at the level of the dies 5 because of their shape or of the mechanical operation to be performed such as deep drawing, the transverse strips 36 are preferably chosen. In fact in the tool 1, each time the punches 6 and the blank holder 12 are removed, the transverse strips 36 pushed by the movable studs 18 under the action of the springs 33, 34, pass from their low position to their high position , raise the sheet metal strip 7 (FIG. 2) over the entire width of the latter, peel it off, that is to say free it up or lift it up, effectively from the dies 5 and do not deform it. When the metal strip or sheet metal 7 is not wide but fragile, the longitudinal strips 38 alone (FIG. 6) or the longitudinal strips 38 and transverse strips 36 (FIG. 8) are selected to avoid any break in the metal strip 7. In tool 1, the guide and release system 14 of the metal strip or sheet metal 7 may be provided with transverse strips 3 alone or with longitudinal strips 38 and with grooved coils or rollers 40 or another combination of these guides 16, not shown. A change of guides 16 in the guidance and release or lifting system 14, which consists in dismantling the fixing screws 22 or ball pins, in replacing the old guide by another guide of a different type, on the upper ends of the movable studs 18, and to reassemble the fixing screws 22, is easy and quick. It follows that in the tool 1 the guide and release system 14 is easily adaptable both to the width of the metal strip or sheet 7, to the dimensions of the parts to be manufactured, or to their size; to the mechanical operations to be carried out in this metal strip or sheet metal 7 which may or may not cause the latter to jam in the matrix 5. The shim or adjustment stop 30 cooperates with the shoulder 29 of the hollow or longitudinal flat 24 (FIG. 2 ) to determine the travel of movement of the movable studs 18 going from their low position to their high position consequently the lift or release travel of the metal strip or sheet metal 7 with respect to the matrix 5 which is generally at the level from the low position of the movable studs 18. The thinner the shim or stop 30, the greater the lift or release stroke of the metal strip or sheet 7. When a workpiece is flat, a small lift stroke of the metal strip or sheet 7 defined by a relatively thick block or stop is sufficient. When a workpiece is bulky, a large lift stroke of the metal strip or sheet 7 is necessary and a shim or stop 30 of small thickness is used. In tool 1, during a descent of the slide 4 of the press 2, the blank holder 12 pushes down the strip of metal or sheet metal 7 and the movable pads 18, compressing the springs 33 and 34, and the upper shoulder 28 formed in these movable studs 18 by their longitudinal recess 24, abuts against the upper surface of their wedge or stop 30 and defines the low position of these studs 18 while during a rise of the slide 4, the clamp -flan 12 follows the latter, releases the metal strip or sheet 7 and the movable studs 18 which, under the thrust of the springs 33, 34, move upwards until the lower shoulder 29 formed in these studs 18 by their longitudinal recesses or flats 24 abuts against the lower surface of their wedge or stop 30 and defines the high position of these movable studs 18. The adjustment of the vertical lifting stroke of the metal strip or sheet 7 is linked to the stroke of the slide 4 of the press 2 and the characteristics of the band 7 for compliance er two imperatives, that of a sufficient raising so that the parts of the band 7 arched downwards pass over the dies and elements of the lower part of the tool 1, and that of a limited raising so that the parts of the strip 7 bent upwards do not catch on the blank holder 12, which makes it possible to avoid a risk of catching the strip 7 in the tool 1, of deformation and even blocking of this strip 7. The wedge or stop 30 has, in the example illustrated in FIG. 2, a shape of an S, the upper end of which cooperates with the shoulder 29 of the hollow or flat 24 and the lower end receives the screw 32 which fixes the shim or stop 30 to the bottom flange 8 of the tool 1. An adjustment of the lift or release stroke of the metal strip or sheet 7 results in a change of shim or stop 30 by dismantling and reassembly of the screw 32. As a result, this adjustment of the guidance and release system 14 is also easy and quick.

To further facilitate such an adjustment, non-limiting variants of the shims or stops 30 are shown in FIGS. 9 to 11. In a first variant shown in FIG. 9, a shim or stop 42 has an S shape, the two of which laterally projecting ends serving as adjustment shims have different thicknesses chosen and the body carrying a central hole 43 for the passage of the fixing screw 32.

In a second variant shown in FIG. 10, a shim or abutment 44 in a V, the laterally projecting ends serving as adjustment shims have different thicknesses chosen, and the body carrying a central hole 45 for the passage of the fixing screw 32 .

In a third variant shown in FIG. 11, a multi or multi-stop 46 in a star shape whose laterally projecting ends serving as adjustment shims have different thicknesses and the body carrying a central hole 47 for the passage of the fixing screw 32.

Claims (13)

1. Press tool provided with a system for guiding and releasing a metal strip (7) running through the tool between dies (5) and punches (6), characterized in that it comprises in an economical execution of a successive manufacture of several pieces of predetermined dimensions and different shapes, a guide and release system (14) of the metal strip (7), provided with adjustable sliding means (15) and means interchangeable (16) which make it efficient, adjustable and adaptable both to certain preselected widths and to the degrees of fragility of the metal strips used (7), to certain predetermined dimensions in height of the parts to be manufactured, and to the various mechanical operations carried out by the tool in this strip (7). 2. Tool according to claim 1, characterized in that the guide and release system (14) of the metal strip (7) comprises on the one hand several vertically mobile supports (15) with adjustable stroke between their high positions and low, implanted in a lower fixing sole (8) of the tool, regularly spaced along the path of this metal strip (7) outside the active areas of the dies (5) and punches (6), diametrically opposed by pair on the two longitudinal sides of this strip (7) and constantly resiliently recalled in their high position, and on the other hand a range of guides of choice, interchangeable and removable (16), mounted on the upper ends of these supports - ( 15) to support, release and guide this metal strip (7) in its movement. 3. Tool according to claim 3, characterized in that in the guidance and release system (14), the support (15) comprises a fixed vertical sheath (17) implanted in the lower fixing sole (8) of the tool, a movable stud - (18) sliding vertically in the bore of this sleeve (17) by its lower part to define its high and low positions, and carrying a guide - (16) by the end of its upper part, and a spring system (20) which, mounted between the bottom of the fixed sheath (17) and the lower part of the movable stud (18), tends to push this stud axially towards the outside of this sheath (17), in the high position of this stud. 4. Tool according to claim 3, characterized in that the support (15) of the guidance and release system (14) comprises a movable stud (18) provided with a longitudinal recess or flat (24) forming an upper shoulder ( 28) and a lower shoulder (29), and a protruding wedge or stop (30) fixed on the lower fixing sole (8) of the tool cooperating by its lower surface with the lower shoulder (29) of the movable stud ( 18) to determine the high position of this movable stud (18), in other words that of this support - (15). 5. Tool according to one of claims 3 and 4, characterized in that the support (15) of the guide and release system (14) comprises a movable stud (18) provided with a recess or longitudinal flat (23) , and a lug or stop (25) fixed on the lower fixing sole (8) of the tool, cooperating with this longitudinal recess or flat - (23) of the stud (18) to prevent any rotation of the latter around its axis, while allowing its axial displacement. 6. Tool according to one of claims 2 to 5, characterized in that the guide and release system (14) comprises interchangeable and removable guides (16) in the form of transverse strips (36) with guide grooves (37), longitudinal strips (38) with a longitudinal guide groove (39) and coils or rollers (40) with a guide groove (41). 7. Tool according to claim 6, characterized in that in the guide and release system (14), the transverse strips (36) comprises several dimensions of guide grooves (37) each corresponding to a predetermined metal strip width (7) usable in the tool. 8. Tool according to claim 6, characterized in that in the guide and release system (14), the longitudinal strips (38) comprises several widths respectively defining in their mounting in pairs and opposite, several dimensions of guide grooves - (39) each corresponding to a predetermined metal strip width (7) usable in the tool. 9. Tool according to claim 6, characterized in that in the guide and release system (14), the coils or grooved rollers - (40) comprises several diameters defining respectively in their mounting in pairs and vis-à-vis screw, several dimensions of guide grooves (41) each corresponding to a predetermined metal strip width (7) usable in the tool. 10. Tool according to claim 4, characterized in that the support (15) of the guide and release system (14) comprises a wedge or abutment (30, 42) in S, at least one of the laterally projecting ends of which ensures the function of wedge or stop. 11. Tool according to claim 10, characterized in that in the support (15) of the guide and release system (14), the shim or stop in S - (42) comprises two ends ensuring the function of shim or stop of adjustment provided with different predetermined thicknesses. 12. Tool according to claim 4, characterized in that the support (15) of the guide and release system (14) comprises a wedge or stop - (44) in V whose two laterally projecting ends ensuring the function of wedge or adjustment stops are provided with different predetermined thicknesses. 13. Tool according to claim 4, characterized in that the support (15) of the guidance and release system (14) comprises a multi or multi-stop (46) star whose laterally projecting ends ensuring the function of wedge or stop of adjustment have different predetermined thicknesses.

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