FR3020581A1 - METHOD AND DEVICE FOR REMOVING PREDECUTED PIECES FROM A SHEET OF MATERIAL AND AN EJECTING MEMBER FOR SUCH A DEVICE - Google Patents

Abstract

Device (1) for removing precut pieces (21) from a sheet (20) of material comprising an upper die (2) carrying at least one ejection member (3), a lower die (4) equipped with less a breakthrough (5) adapted to be covered by a pre-cut piece (21) of the sheet (20) of material, said matrices (2, 4), mounted movable in the direction of a connection and a spacing, presenting in the close state, a position in which the or each ejection member (3) partially penetrates through its head (8), inside a piercing (5) provided with at least two stops (10); ) of the lower matrix (4). The ejection member (3) has a cylindrical body (6) which, in its transition zone with the head (8), has a shoulder (9) capable of occupying a high position, in which it extends to least partially above the space left free between two abutments (10) and a low position, in which it extends at least partially between said abutments (10) at a level below that corresponding to the surface (11) bearing formed by said stops (10)

Description

The present invention relates to a method and a device for removing pre-cut pieces, in particular scrap, from a sheet of material comprising cuts or the like, as well as an ejection member for such a device. It relates more particularly to a device for eliminating pre-cut pieces comprising an upper die carrying at least one ejection member, a lower die equipped with at least one breakthrough capable of being covered by a pre-cut piece of the sheet of material, said dies being mounted movable in the direction of a coming together and a spacing and having, in the close state, a position in which the or each ejection member which is in the form of an elongate body couplable by one from its ends to the upper die, partially penetrates, through its opposite end portion, referred to as a "head" within a breakthrough of the lower die, this bore being provided with at least two abutments projecting from the interior of said breakthrough, to provide a bearing surface of the pre-cut piece to be separated. It is known that in order to eject a pre-cut piece more quickly, it is necessary to rotate it to position it perpendicular to the sheet from which it is made. In this position, the pre-cut piece offers less resistance to the air and therefore falls, by gravity, more quickly. However, such a technique requires precise guidance and safe maintenance of the pre-cut piece to ensure its pivoting and drive on the move.

So far, the recommended solutions, where the ejection member is in the form of a blade, are unsatisfactory. An object of the present invention is therefore to provide a device of the aforementioned type whose design allows a safe guidance of the pre-cut piece over the entire stroke of the ejection member, without risk of sliding said pre-cut pieces or accumulation by stacking pre-cut pieces at the free end of the ejection member as the operation of the device. To this end, the subject of the invention is a device for eliminating pre-cut pieces, in particular scrap, from a sheet of material comprising sections or the like, this device comprising an upper die carrying at least one ejection member, a lower die equipped with at least one breakthrough adapted to be covered by a pre-cut piece of the sheet of material, said matrices being movably mounted in the direction of an approximation and a spacing and having, in the close state, a position in which the or each ejection member, which is in the form of an elongate body couplable by one of its ends to the upper die, partially penetrates, through its opposite end portion called the head, into the interior a breakthrough of the lower die, this breakthrough being provided with at least two abutments protruding inside said breakthrough to provide a bearing surface of the piece cut to separate, characterized in that for the or at least one of the ejection members, the body of said ejection member is a cylindrical body which has in its transition zone with the head of said member a section greater than that of the head to form a shoulder, in that this shoulder is able to occupy at least two positions, one, said high position, in which it extends at least partially above the space left free between two stops, the other, said low position, wherein it extends at least partially between said stops at a level less than that corresponding to the bearing surface formed by said stops, in that this shoulder is adapted to to move from the high position to the low position by cutting a line passing through the free ends of said stops, in that at least a portion of the head recessed from the body extends over at least a portion of the path followed by said shoulder ent when it passes from the high position to the low position, facing the edge of the breakthrough extending between said stops, and in that the head of said ejection member is provided at its top with at least three tip teeth, distinct, of identical length greater than 1 mm.

The cylindrical shape of the body of the ejection member gives the latter a rigidity preventing bending during the ejection phase, by pressing the pre-cut piece, thus ensuring a secure positioning of the head of said ejection member.

The presence of at least three teeth makes it possible to exert a sure support on the precut piece, without risk of sliding of said piece or of skewing of the pre-cut piece on the teeth. The presence of a shoulder and its relative positioning relative to the stops makes it possible to complete the training of the pre-cut piece without harming, or the role of the stops, nor the role of the shoulder. In addition, this relative arrangement allows a large number of stop designs without impairing the operation of the assembly. Such a device also makes it possible, due to the small bulk of the ejection members, to adapt to a large number of forms, including complex, pre-cut pieces. Preferably, the head of said ejection member has, at the right of said shoulder, a flat passing through the apex of at least two of the teeth. With this design, the teeth are closer to the guide zone of the ejection member. They can remain in contact with the pre-cut piece during most of the pivoting phase of said pre-cut piece by extending in the immediate vicinity of this pivoting zone. Preferably, the line passing through the free ends of the stops extends in or parallel to the plane passing through the flat. This results in optimal guidance. Preferably, the shoulder of said body is spaced apart from the top of the head by a distance of between 5 and 8 mm. Preferably, at least some of the teeth have a general pyramidal shape. Preferably, the or at least one of the ejection members is associated with a pusher carried by the upper die, ejection member and associated pusher being able to penetrate into the same breakthrough in the close position of the dies, the free ends the pusher and the ejection member being axially offset with the free end of the pusher positioned in front of that of the ejection member to penetrate first into said piercing. This arrangement facilitates the pivoting of the pre-cut piece. Another subject of the invention is an ejection member of the type in the form of an elongate body which can be coupled at one end to the upper die of a device and which is able to penetrate partially through its part. opposite end called the head, inside a breakthrough of the lower die of said device, characterized in that the body of the ejection member is a cylindrical body which, in its transition zone with the head 15 of said member, a shoulder at which the head extends back said body, said shoulder being spaced from the top of the head by a distance of between 5 and 8 mm, and in that the head of said ejection member is provided at its apex of at least three distinct tip teeth, of identical length greater than 1 mm. Preferably, said ejection member is a monolithic piece, and the head of said ejection member has, at the right of said shoulder, a flat passing through the apex of at least two of the teeth, flat and shoulder being made of one piece. The invention further relates to a method for eliminating a pre-cut piece, in particular a scrap, of a sheet of material comprising a cut or equivalent using a device as described above, said pre-cut piece being positioned in overlapping of a breakthrough of the lower die, characterized in that said method comprises, by progressive approximation of the dies, a first step of supporting the teeth of the ejection member (s) on said precut piece, a second step of penetration of the ejection member inside the piercing during which said precut piece is, by cooperation of the abutments and the ejection member, driven in pivotal displacement to a position s in which the slice of said pre-cut piece comes opposite the shoulder of the ejection member and a third step of pushing said precut piece by supporting said shoulder on the slice of said pre-cut piece. The invention will be better understood on reading the following description of embodiments, with reference to the appended drawings in which: FIG. 1 represents, in the form of schematic views in section and from below, before separation, the position a pre-cut piece of a sheet of material on the lower die with the upper die equipped with the separation members. - Figure 2 shows, in schematic sectional view, the pivoting movement of the pre-cut piece of a sheet of material in the lower die breakthrough. FIG. 3 is a diagrammatic view in section and from below of the position of a pre-cut piece of a sheet of material between the abutments of the lower die and the flat part of the ejection member after pivoting; . FIG. 4 is a diagrammatic view in section and from below, in the rotated state of a pre-cut piece of a sheet of material, the step of pushing said pre-cut piece by the support of said shoulder of the ejection member on the edge of said pre-cut piece. FIGS. 5 to 7 show, in the form of schematic views in section and also, in FIG. 5, in the form of a view from below, the different stages of separation of a pre-cut piece of a sheet of material with the use an elastic stop; FIGS. 8 to 10 show, in the form of schematic views in section and also, in FIG. 8, in the form of a view from below, the various steps of separating a pre-cut piece from a sheet of material with the use a pusher associated with the ejection member. - Figure 11 shows a perspective view of an ejection member. - Figure 12 shows, in schematic views, various embodiments of an ejection member. As mentioned above, the device 1, which is the subject of the invention, makes it possible to eliminate pre-cut pieces 21, in particular scraps, from a sheet of material comprising cuts or the like. These precut pieces 21 can still be called falls. Generally, the sheet 20 of material is for example constituted by a pre-cut cardboard blank, each precut corresponding to a piece 21 to be subsequently eliminated. This sheet 20 of material, after having undergone a number of operations, is brought and placed on the separation surface of a lower die 4, so that the pre-cut piece 21 covers a breakthrough 5 of the lower die 4. This breakthrough 5 generally has a homothetic profile to the pre-cut profile made in the sheet of material. An ejection member 3 is moved downwardly through this piercing 5, so as to exert pressure on the pre-cut piece 21 to allow its separation from the sheet 20 of material. This ejection member 3 is carried by an upper die 2, which is generally in the form of a simple wooden board. This ejection member 3 is in the form of a cylindrical elongated body 6, coupled at one of its ends, generally by interlocking, to the upper die to protrude from this die in a plane. generally perpendicular to the support plane of said matrix. The opposite end portion of this ejection member 3 is called the head 8 of said ejection member 3. This ejection member 3 is fit, under the effect of a combination of the upper and lower matrices 2 mounted 4 movable in the direction of a rapprochement and a spacing, to enter through its head in the or a breakthrough of the lower matrix 4. This breakthrough 5 is provided with at least two abutments 10 projecting inside said pierce to provide a bearing surface 11 of the pre-cut piece 21 to be separated. These stops thus make it possible to momentarily retain the pre-cut piece in order to promote its separation from the sheet, under the pressure of the ejection member, during a relative displacement between the ejection member and the lower die.

In the example shown in Figure 1, the device comprises a breakthrough 5 of rectangular shape and two stops 10 formed along a longitudinal edge of said piercing. These stops 10 are formed by a cut, here of triangular shape of said edge of the lower die 4, which is a wooden matrix in the form of a simple plate.

In the example shown in FIG. 5, the abutments are elastically deformable abutments in the general shape of a square, with an implantation branch in the thickness of the matrix and a so-called free arm partially bearing on the surface of the abutment. the die before protruding inside the breakthrough of the die to provide a support zone forming a stop of the pre-cut piece to be separated. In the example shown in Figure 8, these stops are formed by metal tongues reported. In the examples shown in Figures 1 and 5, the device comprises three ejection members aligned along a line substantially parallel to one of the longitudinal edges of said piercing. One of the ejection members is positionable between two stops. The other ejection members are positionable between an abutment and a transverse edge of said piercing. Each ejection member here has, in its transition zone with the head, a section greater than that of the head to form a shoulder 9 at which the head extends recessed. This shoulder can, as illustrated in Figure 12, affect a large number of shapes. This shoulder may be an annular shoulder forming a collar of the body or an annular surface around the head, at the transition zone with the head. This shoulder can still be in the form of a notch. This solution, in which the head 8 of the ejection member 3 has the right of said shoulder 9 a flat 13 is preferred. Flat and shoulder form a right angle between them. In this embodiment, the line XX 'passing through the free ends of the stops 10 extends in or parallel to the plane passing through the flat surface 13. Preferably, the shoulder, regardless of its embodiment, is spaced from the top of the head 8 by a distance of between 5 and 8 mm. Regardless of the shape of the shoulder, the head of the ejection member 20 thus has a portion set back from the body. In a manner that is characteristic of the invention, at least a portion of the head 8 set back from the body 6 extends over at least a portion of the path followed by said shoulder 9 during its passage from a high position to a low position. , during the approximation of the dies, facing the edge of the breakthrough 25 carrying said stops. In particular, the ejection member disposed between two stops has at least a portion of its head set back from said body which extends over at least a portion of the path followed by said shoulder when it passes from a high position. at a low position, facing the edge of the breakthrough 5 extending between said stops 10.

The head 8 of each ejection member 3 is provided, at its apex, with at least three, preferably at least five teeth cut to a point, that is to say with apex. In the example shown, these teeth are faceted teeth of general pyramidal shape. When the head 8 of said ejection member 3 has the right of said shoulder 9 5 a flat portion 13, this flat, which forms the part of the recessed head, passes through the top of two of the teeth. The ejection member positionable between two stops is positioned on the upper die, so that the shoulder of said ejection member is adapted to occupy two positions, one said high position in which it extends at least partially above the space left free between two stops 10, the other said low position in which it extends at least partially between said stops, at a level less than that corresponding to the bearing surface formed by said stops and in that it is able to move from the high position to the low position by cutting the line XX 'passing through the free ends 15 of said stops. The other ejection members are positionable between a stop and a transverse edge of the breakthrough. The shoulder of these other ejection members is therefore able to occupy a high position in which it extends above the space left free between a stop and a transverse edge of the breakthrough and a low position in which it extends at least partially between a stop and a transverse edge of the breakthrough to a level less than that corresponding to the bearing surface 11 formed by said stops and in that it is able to pass from the high position to the lower position by cutting the line XX 'passing through the free ends of the stops.

In the example shown in FIGS. 8 to 10, each ejection member 3 is associated with a pusher 14 also carried by the upper die 2. This pusher 14 is, like the ejection member 3, in the form of a cylindrical elongate body, one end, forming a head, is provided with pointed teeth. However, this pusher is, unlike the ejection member, devoid of shoulder in the transition zone between head and body. In addition, this pusher is of apparent length greater than the length of the ejection member, so that the free end of the pusher enters the breakthrough before the free end of the ejection member, when a reconciliation of said matrices. During this approximation of said matrices, the teeth 12 of said ejection member 3 come, in a first step, on the pre-cut piece which is positioned to overlap a breakthrough of the matrix, as shown in FIG. The continuation of the approximation of the matrices Io generates, by cooperation of the ejection member and stops of the breakthrough, a separation of the pre-cut piece from the remainder of the sheet and a pivotal displacement of the pre-cut piece around the free end of the the abutment (s), while being guided by the top of the head of the punch or the ejection member, so that the pre-cut piece tends to extend in a vertical plane perpendicular to the horizontal plane of opening of the breakthrough or perpendicular to the bearing surface formed by said stops. In the course of continuing the approximation of the dies, the shoulder is supported on the edge of said pre-cut piece to help continue its training in moving through the breakthrough until the exit of said breakthrough.

Claims (9)

REVENDICATIONS1. Device (1) for eliminating precut pieces (21), in particular rejects, from a sheet (20) of material comprising sections or the like, this device (1) comprising a top matrix (2) carrying at least one member ( 3) ejection, a lower die (4) equipped with at least one breakthrough (5) adapted to be covered by a pre-cut piece (21) of the sheet (20) of material, said matrices (2, 4) being movably mounted in the direction of approaching and spacing and having, in the close state, a position in which the or each ejection member (3), which is in the form of a body (6) elongate couplable by one (7) of its ends to the upper die (2), partially penetrates, through its opposite end portion called head (8), into a breakthrough (5) of the die (4) ), this piercing (5) being provided with at least two stops (10) projecting inside said piercing (5), po ur make a support surface (11) of the pre-cut piece (2) to be separated, characterized in that for the or at least one of the ejection members (3), the body (6) of said member (3) ejection is a cylindrical body (6) which has in its transition zone with the head (8) of said member (3), a section greater than that of the head to form a shoulder (9), in that this shoulder (9) is able to occupy at least two positions, one, said high position, in which it extends at least partially above the space left free between two stops (10), the other, said low position, in which it extends at least partially between said abutments (10) at a level less than that corresponding to the bearing surface (11) formed by said abutments (10), in that this shoulder (9) is able to pass from the high position to the low position by cutting a line (XX ') passing through the free ends of said stops (10), in that at least a portion of the head (8), set back from the body (6), extends over at least a portion of the path followed by said shoulder (9) during its passage from the high position to the low position, view of the edge of the bore (5) extending between said stops (10), and in that the head (8) of said ejection member (3) is provided at its apex with at least three teeth (12). in point, distinct, of identical length greater than 1 mm. 2. Device (1) according to claim 1, characterized in that the head (8) of said member (3) ejection has, right of said shoulder (9), a flat (13) passing through the apex of minus two teeth (12). 3. Device (1) according to claim 2, characterized in that the line (XX ') passing through the free ends of the stops (10) extends in or parallel to the plane passing through the flat (13). 10 4. Device (1) according to one of the preceding claims, characterized in that the shoulder (9) of said body (6) is spaced from the top of the head (8) by a distance of between 5 and 8 mm. 15 5. Device (1) according to one of the preceding claims, characterized in that at least some of the teeth (12) have a generally pyramidal shape. 6. Device (1) according to one of the preceding claims, characterized in that the or at least one of the ejection members (3) is associated with a pusher (14) carried by the upper die (2). , member (3) ejection and pusher (14) associated being able to penetrate into a single bore (5) in the close position of the dies (2, 4), the free ends of the pusher (14) and the member ( 3) being offset axially with the free end of the pusher (14) positioned in front of that of the ejection member (3) to penetrate first into said pierce (5). 7. Ejection member (3) of the type in the form of an elongate body (6) couplable by one (7) of its ends to the upper die (2) of a device (1) according to the present invention. one of claims 1 to 6, and able to partially penetrate, through its opposite end portion called head (8), inside a piercing (5) of the lower die (4) of said device (1) , characterized in that the body (6) of the ejection member (3) is a cylindrical body (6) which has, in its transition zone with the head (8) of said member, a shoulder (9) at at which the head (8) extends back from said body, said shoulder being spaced apart from the top of the head by a distance of between 5 and 8 mm, and in that the head (8) of said member (3) is ejection is provided at its apex with at least three distinct tip teeth (12) of identical length greater than 1 mm. 8. ejection member (3) according to claim 7, characterized in that said ejection member (3) is a monolithic piece, and in that the head (8) of said ejection member (3) has , at the right of said shoulder (9), a flat (13) passing through the apex of at least two of the teeth (12), flat and shoulder being made in one piece. 9. Process for removing a pre-cut piece (2), in particular a scrap, from a sheet (20) of material comprising a cut or equivalent using a device (1) according to one of claims 1. at 6, said pre-cut piece (21) being positioned overlapping a breakthrough (5) of the lower die (4), characterized in that said method comprises, by progressively moving the dies (2, 4), a first step supporting the teeth (12) of the ejection member (s) (3) on said pre-cut piece (21), a second step of penetration of the ejection member (3) inside the breakthrough (5). ) during which said pre-cut piece (21) is, by cooperation of the abutments (10) and the ejection member (3), driven in pivotal displacement to a position in which the slice of said piece ( 21) precut comes next to the shoulder (9) of the ejection member (3) and a third step of p foamed said piece (21) pre-cut by pressing said shoulder (9) on the edge of said piece (21) pre-cut.