EP4547418A1 - Module for the deep redrawing of metal end pieces and machine comprising at least one module - Google Patents

Abstract

The invention relates to a redrawing module comprising a driving plate (2) coupled to a gear motor centred on a central axis (Z) and rotated about a central axis of rotation (A); a rotary cylinder centred on the central axis (Z) and rotated about the central axis (Z) by the gear motor, comprising a punch-bearing press (31) and a die-bearing ring (33), each punch (32) being movable in translation parallel to the central axis (Z) and being coupled to the driving plate (2) by one of its ends. The redrawing module further comprises means for adjusting the angle of inclination (α) of the axis of rotation (A) of the driving plate (2) relative to the central axis (Z).

Description

DEEP DRAWING MODULE FOR METAL END TIPS, AND

MACHINE COMPRISING AT LEAST ONE MODULE

Technical area

The present invention relates to a machine for deep redrawing of metal ends. Such stamped parts can for example be used in the production of containers, capping or over-capping means, etc.

Prior art

The deep redrawing of a metal tip (or blank or blank) consists of shaping a pre-stamped blank by the action of a tool, such as a punch coupled to a blank holder, forcing the tip to penetrate a matrix. The pre-stamped stock, in the form of a cup, can undergo one or more successive re-stampings, but retains its initial thickness and remains smooth on the surface.

The successive deep redrawings of thin metal blanks are generally carried out using a so-called “continuous kinematic” machine made up of one or more rotating barrels mounted in series, mechanically synchronized by blank feeding devices and devices for transferring re-drawn stock, in the form of star wheels. For example, the machine can be composed of two barrels in series, namely a so-called “recovery” barrel, followed by a so-called “finishing” barrel. Each barrel comprises slides carrying tools mounted directly above a die-carrying plate, and the barrels are rotated by means of gears coupled to a single reduction motor. A crude inlet star wheel to successively supply raw materials to the recovery barrel, is positioned upstream of the recovery barrel, and a crude transfer star wheel is positioned between the barrels to transfer the raw materials from the barrel return to the finishing barrel. In practice, the feeding of the raw materials into the star wheels generates a jerky movement accompanied by shock of the crude arriving in a cell of the star wheel, which can induce a risk of poor reception of the rough materials in the cell and variations in the speed advance of the line of crudes which are detrimental to the good regularity of operation and therefore limiting as to the rate of absorption of the crudes by the barrels. Furthermore, synchronization between the barrels and the star wheels is obtained by a set of synchronous belts. Thus, the different movements or movement of the different moving parts of the installation, as well as their synchronization, are generally controlled via mechanical means which require tedious adjustments.

In addition, the stroke of the slides which is defined by the deepest ends of the range to be stamped, is fixed during the manufacture of the machine, and cannot be modified to adapt the machine to another range.

Presentation of the invention

The present invention therefore aims to propose a more advantageous solution for the re-stamping of bits, of simple structure and which does not require tedious adjustments.

The invention aims in particular to propose a more efficient, modular, compact solution, easy to install, which makes it possible to set up a single-barrel or multi-barrel stamping line depending on the number of intermediate passes necessary or the desired production.

The subject of the invention is therefore a module for deep redrawing of metallic cylindrical end pieces, for example made of aluminum, the stamping module comprising:

- a fixed frame comprising a horizontal table forming a main surface and carrying a central reference axis perpendicular to said main surface;

- a circular inductor plate coupled to a gear motor centered on the central axis, and driven in rotation around a central axis of rotation;

- a rotating barrel centered on the central axis and driven in rotation around the central axis by the gear motor, the barrel comprising a slide-carrying turret and a die-carrying crown centered on the central axis, the slides being arranged around of the central axis parallel to each other, each slide being movable in translation parallel to the central axis and being coupled to the inducing plate by one of its ends, the other end of the slide being provided with stamping tools , such as a punch coupled with a blank holder, positioned directly above one of the dies. According to the invention, the restamping module further comprises means for adjusting the angle of inclination of said axis of rotation of the inductor plate relative to said central axis. Adjusting the inclination of the induction plate thus allows adjustment of the stroke of the slides to a minimum compatible with the height of the stock to be re-stamped and the depth of re-stamping required, while reserving an optimal active working angle.

In practice, the gear motor can be a constant torque and variable speed gear motor.

Advantageously, these means for adjusting the angle of inclination comprise at least one stirrup plate comprising a support portion carrying the geared motor and from which the two arms of the stirrup extend. The support portion is pivotally mounted on the frame around a horizontal pivot axis, this pivot axis extending parallel to the main surface and being perpendicular to the central axis. In addition, the end of each arm is removably attached to the frame. Thus, the modification of the angle of inclination of the induction plate is carried out by changing the position of the arms relative to the frame.

According to a variant, each arm of the stirrup can be fixed to the frame by means of a strap whose length corresponds to a predefined angle of inclination of the inducing plate, and more precisely of its axis of rotation. Thus, by interchanging straps of different lengths, it is possible to modify the angle of inclination of the induction plate. According to another variant, each strap may comprise several attachment points to the frame, each attachment point corresponding to an angle of inclination of the axis of rotation of the inducing plate. According to another variant, it is possible to provide several points of attachment of the arms on the frame, each of the fixing points corresponding to a predefined angle of inclination of the induction plate.

In operation, each of the slides coupled to the induction plate moves towards or away from the die-carrying crown depending on their angular position on the induction plate. The angle of inclination of the axis of rotation of the induction plate thus fixes the stroke of the slides, and the adjustment of the inclination of the induction plate therefore allows optimal adjustment of the stroke of the slides. In practice, in the case of a re-stamping line made up of several stamping modules mounted in series or in parallel, the stroke of the slides can be different between two barrels and can be optimized for each re-stamping module by simple modification of the the inclination of its inducing plate. The possibility of adjusting the stroke of the slides of each barrel to a minimum saves production time. As an indication, the inventors estimate a production gain, per active slide, of 45% for blanks to be stamped with a length (or depth) of 60 mm, and a production gain, per active slide, of 350% for blanks to be stamped. stamp length (or depth) 25 mm.

Each slide is advantageously coupled to the inducing plate via an articulated means, such as a connecting rod, configured to transmit to said slide a sinusoidal translation movement parallel to the central axis, during rotation of the inducing plate. The depth of drawing of the slides can be adjusted by lengthening or shortening the connecting rods.

Usually the travel of the slide is defined between a position called “top dead center” and a position called “bottom dead center”. In practice, the rotation of the inducing plate and the movement of the slides are preferably synchronized so that the introduction of a tip into a die (and therefore the introduction of a tip into a cell) coincides with the positioning of the slide at its top dead center. Furthermore, the ejection of the re-stamped tip for transfer to another re-stamping module is preferably carried out when the corresponding slide is at its top dead center, and the final ejection of the tip having undergone a final pass is preferably carried out when the corresponding slide is at its bottom dead center, and preferably by air jet.

According to one variant, the barrel can carry nine slides. In this variant, the original diameter of the barrel can be 320mm. This variant offers a compact restamping solution with optimal restamping speed without tearing. According to another variant, the barrel can carry 12 slides.

In practice, the axis of rotation of the inductor plate and the central axis coincide at the center of the inductor plate. An articulated homokinetic transmission can be implemented to ensure the mechanical coupling between the geared motor carrying the axis of rotation and the slide-carrying turret carrying the central reference axis. The inductor plate and the barrel are both independently coupled to the gear motor, for example via an Oldham type coupling.

According to one embodiment, the restamping module may also include:

- a circular selector plate with external teeth, centered on the central axis and secured to the die-carrying crown, the selector plate comprising cells for receiving bits defined between the successive teeth, the internal surface of each cell being configured to wrap the external surface of a cylindrical end piece over an angle portion close to 180°. Thus, advantageously, the internal surface of each cell is of semicircular shape and is thus configured to envelop the external surface of a cylindrical end piece over 180°. In practice, each cell is positioned directly above a matrix.

The selector plate is thus configured to receive and correctly position the blanks directly above the dies so as to allow the stamping of the blanks in optimal conditions. The selector plate could also be configured to allow a direct supply of crude oil to the barrel, so as to save the use of star wheels upstream or downstream of the barrel, and therefore complex mechanical means of synchronization and tedious maintenance.

Thus, the external profile of the selector plate between two successive tooth tips advantageously presents a concave semi-circular portion (or turned towards the outside of the plate) forming the hollow of the tooth and therefore the tip receiving cell, and a curved portion (or a spiral portion) convex (or turned inwards) forming the back of the tooth. The curved portion is preferably configured to ensure a progressive trajectory of the raw materials towards the receiving cell.

In practice, each semicircular portion thus has two ends, namely a first end forming the tip of a tooth of the selector plate, and a second end from which the curved portion extends. The first end is located on a first circle centered on the central axis, and the second end is located in a second circle also centered on the central axis and of smaller diameter than that of the first circle. There curved portion joins the first end of an adjacent semicircular portion so as to form another tooth of the selector plate. Thus, all the tips of the selector plate teeth are located on the first circle.

To ensure the progressive delivery of the raw materials into each of the receiving cells, the curved portion advantageously has a profile of the type corresponding to an arc of an Archimedean spiral developed over 2n whose center of rotation coincides with that of the selector plate .

Under these conditions, the arrival trajectory of the stock on the curved portion (corresponding to the back of the tooth) is preferably parallel to an axis perpendicular to the tangent at a predefined point of the curved portion, preferably at the level of the tip of the corresponding tooth. The re-stamping module may also include a system for ejecting the tips after re-stamping.

Advantageously, when the restamping module is intended to be installed as a recovery module, the ejection system is preferably configured to reassemble the tip after restamping. The ejection system can be in the form of spring plungers attached to each die, or of a set of cam ejectors coupled to each die to reassemble the tip after restamping, when the tip must be transferred to a another restamping module, for example to another rework module or to a finishing module.

Advantageously, when the restamping module is intended to be installed as a finishing module, the ejection system is preferably configured to eject the tip downwards after restamping. The ejection system can be in the form of a jet of air generated by each punch and configured to eject the corresponding tip downward after restamping.

In practice, each blank holder can be a pneumatic pressing piston.

Furthermore, to limit the heating of the slides due to instantaneous overpressure generated by the blank-holding pistons, it is possible to add an overpressure limiting valve to each slide block, and also a thermal cooling device, for example in the form of cooling fins.

According to other alternatives, a restamping module can integrate the selector plate described above with or without the adjustable tilt inducing plate, or can integrate the adjustable tilt inducing plate described above with or without the adjustment plate. selector.

The proposed restamping module is thus an elementary, autonomous and universal module. Its configuration makes it possible to form a re-stamping chain or line by associating several re-stamping modules together according to needs.

Thus, the invention also relates to a deep redrawing machine comprising at least one redrawing module as described above.

Advantageously, when the restamping module comprises a selector plate as described above, the machine can also comprise:

- a tip entry conveyor towards the selector plate, the conveyor preferably being configured to bring the tip to the selector plate following a predefined arrival trajectory. This arrival trajectory is preferably linear and parallel to an axis perpendicular to the tangent at a predefined point of the curved portion, preferably at the level of the tip of the tooth.

For example, the axis of the arrival trajectory of the raw materials passes through the tip of the tooth of the cell in which it must be received and the center of the semi-circle forming said cell. Thus, unlike the configurations of the prior art in which the raw materials arrive following an arrival trajectory parallel to an axis passing through the center of the star wheel, the arrival trajectory of the raw materials in the present solution the axis d The power supply no longer passes through the center of rotation.

In other words, the stock comes into contact with the curved portion following an arrival trajectory perpendicular to the tangent at this point of contact. This point of contact can for example be the tip of the tooth, and the axis of the arrival trajectory preferably passes through the two ends of the cell preceding the cell in which the crude must be received, following the direction rotation of the selector plate. Such a combination makes it possible to bring the raw materials into the dies with a strictly constant feed speed and without parasitic jerks.

In practice, the inlet conveyor comprises a conveyor track coupled to a nozzle-type blowing system, configured to generate a low-pressure laminar air flow to move the end pieces on the conveyor track following said arrival trajectory.

According to one embodiment, the machine comprises a plurality of deep re-stamping modules mounted in series forming a re-stamping line, each re-stamping module being as described above, and the re-stamping module at the start of the line is supplied with bits via the inlet conveyor described above. In addition, in order to allow a fluid and smooth transfer of the bits between two successive restamping modules of the line, the machine can also include:

- a transfer conveyor arranged between first and second successive restamping modules of the line, the transfer conveyor comprising:

. an inlet coupled to the selector plate of the first restamping module and configured to receive the restamped bits ejected by the first restamping module; And . an output coupled to the selector plate of the second restamping module and configured to power the second restamping module.

Advantageously, the transfer conveyor is also coupled to an air blowing system, such as a nozzle, to generate a low pressure laminar air flow, the nozzle being positioned and configured to move, via suction by venturi effect , the tips ejected by the first restamping module into the transfer conveyor and to move these tips towards the second restamping module. Preferably, the transfer conveyor forms a buffer store controlled by proximity detectors, allowing synchronization between two successive barrels.

The combination of the selector plate which allows direct feeding of crude oil to the barrels and the pulsed air conveying system allows a feeding or transfer speed limited only by the performance of the synchronization electronics. This configuration eliminates expensive and polluting mechanical transmissions requiring the use of lubricants, and allows an optimized production speed. Brief description of the figures

Other characteristics and advantages of the invention will emerge clearly from the description given below, for information only and in no way limiting, with reference to the appended drawings, in which:

Figure 1 is a front view of a stamping module according to one embodiment. Figure 2 is a sectional view of one side of the stamping module of Figure 1 with the inclined inductor plate.

Figure 3 is a top view of the stamping module of Figure 1 showing an example of means for adjusting the inclination of the inducing plate.

Figure 4 is a cleaner representation of Figure 3.

Figure 5 is a schematic representation seen from above of the selector plate according to one embodiment.

Figure 6 is a partial schematic representation of the selector plate of Figure 5 illustrating the trajectory of raw materials arriving at the selector plate.

Figure 7 is a front view of an installation implementing two restamping modules from Figure 1.

Figure 8 is a perspective view of the installation of Figure 7.

Figure 9 is a partial representation of the transfer conveyor positioned between the selector plates of the recovery and finishing barrels in the installation of Figure 7.

Mode(s) of carrying out the invention

A stamping module according to one embodiment is illustrated in Figures 1 and 2, and comprises a fixed frame 1 formed of an upper part 11 and a lower part in the form of a horizontal table 12 having a main surface 120 supporting a central reference axis Z perpendicular to said main surface 120. A circular inductor plate 2 coupled to a motor, such as a constant torque and variable speed gear motor, is positioned at the level of the upper part 11 of the frame 1. The motor is configured to drive the inductor plate 2 in rotation around a central axis of rotation A, the axis of rotation A and the central axis Z concurring at the center of the inductor plate 2. The upper part 11 of the frame 1 can comprise two swan-neck walls between which the inducing plate 2 is located.

According to one embodiment, the inducing plate 2 is mounted movable relative to the frame 1 via means for adjusting the inclination of the inducing plate 2. In particular, these means of adjustment are configured to allow adjustment of the angle a formed between the axis of rotation A and the central axis Z.

As illustrated in Figure 3, these inclination adjustment means are advantageously in the form of a stirrup plate 6 comprising a support portion 61 from which the two arms 60 of the stirrup extend. The support portion 61 supports the motor, and is pivotally mounted around a pivot axis X. This pivot axis is coupled to the reduction plate by means of a transmission lantern 20 secured to the support portion 61 of the stirrup plate 6. In other words, the support portion 61 acts as a cradle for the transmission lantern.

The two arms 60 of the stirrup plate 6 are removably fixed to the frame 1, for example via a set of pins 63. In practice, the upper swan-neck part of the frame 1 can include several fixing positions of these pins 63, for example in the form of threaded holes in the walls of the frame. The arms 60 of the stirrup can also be fixed to the frame 1 via straps or flanges 64 whose length corresponds to a predefined angle of inclination of the inducing plate 2 relative to the main surface 120. Thus, whatever either the means of fixing the arms to the frame, the modification of the angle of inclination of the induction plate is carried out by changing the position of the arms relative to the frame.

The stamping module further comprises a rotating barrel 3 centered on the central axis Z. The barrel 3 is coupled to the motor and is rotated around the central axis Z by the motor. Generally speaking, the barrel 3 and the inductor plate 2 are independently coupled to the motor via coupling means 7, such as an Oldham or Oldham cross type coupling. Barrel 3 is composed in particular of a turret 31 carrying slides and a crown 33 carrying dies centered on the central axis Z.

The die-carrying crown 33 positioned parallel to the main surface 120 is centered on the central axis Z and is mounted integral with the turret 31. The crown 33 is therefore provided with a plurality of dies 330 distributed regularly around the axis central Z. The slides 32 are arranged around the central axis Z parallel to each other. Each slide 32 is mounted movable in translation parallel to the central axis Z and is coupled to the inductor plate 2 by one of its ends, the other end of the slide 32 being provided with stamping tools 320, such as a punch coupled to a blank holder, positioned directly above one of the dies 330. The turret 31 carries a plurality of slides 30 or guide rails in translation in a direction parallel to the central axis Z. These slides 30 are distributed regularly on the external surface of the turret 31 around the central axis Z, and the slides 32 are mounted sliding on these slides 30. Each slide 32 is coupled to the inducing plate 2 by one of its ends via a articulated means 4, such as a connecting rod, and the tooling 320 is positioned on the other end of the slide 32. In addition, to limit the heating of the slides 32 due to instantaneous overpressure generated by integrated blank-holding pistons in the slides, it is possible to add pressure limiting valves combined with cooling fins 34 to each slide block.

In operation, each connecting rod is configured to transmit a sinusoidal translation movement to the slide 32 during the rotation of the inducing plate 2. The depth of drawing of the slides can be adjusted by lengthening or shortening these connecting rods. Thus, each of the slides 32 coupled to the inducing plate 2 moves towards or away from the die-carrying crown 33 depending on their angular position on the inducing plate 2, and the angle of inclination a of the axis of rotation A of the induction plate 2 fixes the stroke of the slides 32. Adjusting the inclination of the induction plate therefore allows optimal adjustment of the stroke of the slides.

The die-carrying crown 33 is advantageously surmounted by a circular selector plate 5 configured to allow the direct reception and positioning of the stock at each of the dies 330. The selector plate 5 is centered on the central axis Z and is mounted integral with the crown 33 die holder.

As illustrated in Figures 5 and 6, the profile of the selector plate between two successive tooth tips 52 advantageously presents a cell 51 for receiving a stock and a curved portion 52. Each cell 51 is positioned directly above a matrix 33, and the internal surface of each cell is configured to envelop the external surface of a cylindrical end piece on a corner portion. For example, the internal surface of each cell 51 is of hemicircular shape to envelop the external surface of a cylindrical end piece 8 over 180°.

The exterior profile of the selector plate 5 illustrated in Figure 5 presents, between two successive tooth tips 53, a semicircular portion 51 forming the tip receiving cell, and a curved portion 52 forming the back of the tooth. Each semicircular portion 51 has a first end 510 forming the tip 53 of a tooth of the selector plate, and a second end 511 from which the curved portion 52 extends. The first end 510 is located on a first circle Cl (represented in dotted in Figure 5) centered on the central axis Z, and the second end 511 is located in a second circle C2 (shown in dotted lines in Figure 5) centered on the central axis Z and of diameter less than the diameter of the first circle Cl. The curved portion 52 joins the first end of the adjacent semicircular portion 51. This particular shape of the selector plate ensures a progressive delivery of the raw materials into each of the receiving cells, without requiring the implementation of complex mechanical transmission means, while ensuring an optimized production speed. In practice, the curved portion 52 advantageously has a profile of the type corresponding to an arc of an Archimedean spiral developed on 2n whose center of rotation coincides with that of the selector plate.

Preferably, the end pieces 8 arriving on the selector plate 5 follow a linear arrival trajectory parallel to an axis 80 perpendicular to an axis T. This axis T is preferably tangent to the curved portion 52 preceding (in the direction of rotation of the selector plate 5) the cell 51 in which the tip must be received, for example tangent to the tip of the tooth as illustrated in Figure 6.

Depending on the number of restampings required, a restamping machine can thus include a stamping module or a succession of restamping modules arranged in a chain so as to carry out the different successive passes.

Figures 7 and 8 illustrate an example of an installation implementing two restamping modules, the installation further comprises a rough entry module (not shown in Figure 7) and a rough transfer module (not shown in Figure 7). The machine thus comprises a first re-stamping module 1 A called “resumption” and a second re-stamping module IB called “finishing”. The recovery module IA is coupled upstream to an input conveyor 90. This input conveyor 90 is configured to bring the bits to the selector plate of the recovery module IA, following the arrival trajectory defined above.

In practice, the inlet conveyor 90 integrates a nozzle-type blowing system, configured to generate a low-pressure laminar air flow in order to move the tips on the conveyor track.

A transfer conveyor 91 is also arranged between the two restamping modules IA and IB, to ensure the transfer of the tips from the recovery module IA to the finishing module IB. As illustrated in Figure 9, the inlet 910 of the transfer conveyor 91 is coupled to the selector plate 5 A of the recovery module and receives the tips ejected by the recovery module. The outlet 911 of the transfer conveyor 91 is coupled to the selector plate 5B of the finishing module and feeds the selector plate 5B on the same principle as the input conveyor 90.

To ensure the ejection of the bits, the recovery module IA can be provided with a bit ejection system in the form of spring-loaded pushers attached to each die, or a set of cam ejectors coupled to each die to reassemble the tip after re-stamping.

The transfer conveyor 91 can integrate a nozzle downstream of the inlet 910 to generate a low pressure laminar air flow. The nozzle is notably positioned and configured to induce suction by venturi effect of the tip ejected by the recovery module IA in the transfer conveyor 91 and to push these tips by low pressure laminar flow towards the finishing module IB.

Thus, the raw materials are brought by the input conveyor 90 to the selector plate 5A of the recovery module IA. A first stamping pass is carried out on the stock, then the stamped stock is ejected and moved in the transfer conveyor 91 to be transferred to the selector plate 5B of the finishing module IB to undergo a second stamping pass. The ejection of the tips from the IB finishing module can be ensured by a jet of air generated by each punch to eject the corresponding tip downwards after its re-stamping. The restamping modules of the machine are autonomous, since each is driven by its own motor, and it is possible to adjust the stroke of the slides of a restamping module independently of the stroke of the slides of the other modules.

The solution of the invention thus makes it possible to design a restamping module with minimum dimensions adapted to the forces to be applied and the maximum possible number of punch/die assemblies. The rotational inertia of the module can be drastically reduced and allows rotation speeds much higher than that of current machines, provided that the maximum stamping speeds defined for a long time in this area are respected.

Claims

1. Deep redrawing module for cylindrical metal ends, including: - a fixed frame (1) comprising a horizontal table (12) defining a main surface (120) carrying a central reference axis (Z) perpendicular to said main surface (120); - a circular induction plate (2) coupled to a gearmotor, centered on the central axis (Z), and driven in rotation around a central axis of rotation (A); - a rotating barrel (3) centered on the central axis (Z) and rotated around the central axis (Z) by the gear motor, the barrel (3) comprising a turret (31) carrying slides and a crown (33) die holders centered on the central axis (Z), the slides (32) being arranged around the central axis (Z) parallel to each other, each slide (32) being movable in translation parallel to the axis central (Z) and being coupled to the inductor plate (2) by one of its ends, the other end of the slide (32) being provided with stamping tools positioned directly above one of the dies ( 330); characterized in that the restamping module further comprises: means for adjusting an angle of inclination (a) of said axis of rotation (A) of the inductor plate (2) relative to said central axis (Z). 2. Re-stamping module according to claim 1, characterized in that the means for adjusting the angle of inclination of the axis of rotation (A) relative to said central axis (Z) comprise at least one stirrup plate ( 6) comprising a support portion (61) carrying the inductor plate (2) and from which the two arms (60) of the stirrup extend, the support portion (61) being pivotally mounted on the frame (1) around 'a horizontal pivot axis (X), this pivot axis (X) extending parallel to the main surface (12) and being perpendicular to the central axis (Z), the end of each arm (60) being removably fixed to the frame (1), and the modification of the angle of inclination of the induction plate (2) being obtained by changing the fixing position of the arms (60) on the frame (1). 3. Re-stamping module according to claim 2, characterized in that each arm (60) is fixed to the frame (1) by means of a flange (64) whose length corresponds to a predefined angle of inclination of the axis rotation (A) of the induction plate. 4. Re-stamping module according to claim 3, characterized in that the axis of rotation (A) of the inductor plate (2) and the central axis (Z) of reference coincide at the center of the inductor plate (2). 5. Re-stamping module according to one of claims 1 to 4, characterized in that the re-stamping module further comprises: - a circular selector plate (5) with external teeth (50), centered on the central axis and secured to the die-carrying crown (33), the selector plate (5) comprising cells (51) for receiving bits defined between the successive teeth (50), each cell (51) being positioned directly above a matrix (330) and the internal surface of each cell (51) being configured to envelop the external surface of a tip on a angle portion close to 80°. 6. Re-stamping module according to one of claims 1 to 5, characterized in that it further comprises a system for ejecting the tips after re-stamping: - the ejection system being configured to reassemble the tip after re-stamping, when the tip must be transferred to another re-stamping module; Or - the ejection system being configured to eject the tip downwards after re-stamping, when the re-stamping module is a finishing module. 7. Deep redrawing machine comprising one or more a redrawing module according to one of claims 1 to 6. 8. Re-stamping machine according to claim 7, characterized in that it further comprises a bit inlet conveyor (90) configured to bring the bits to the selector plate (5) following a predefined linear arrival trajectory. 9. Re-stamping machine according to claim 8, characterized in that the inlet conveyor (90) comprises a conveyor track coupled to a nozzle-type blowing system, configured to generate a low-pressure laminar air flow to move the end pieces on the conveyor track following said arrival trajectory. 10. Re-stamping machine according to one of claims 8 or 9, characterized in that it comprises: - a plurality of re-stamping modules (IA, IB) mounted in series and forming a re-stamping line, each re-stamping module being according to one of claims 1 to 6, said inlet conveyor (90) supplying the module with bits re-stamping positioned at the start of the line, - a transfer conveyor (91) arranged between first and second successive restamping modules of the line, the transfer conveyor comprising: . an inlet (910) coupled to the selector plate (5 A) of the first re-stamping module (1 A) and configured to receive the re-stamped bits and ejected by said first re-stamping module; And . an output (911) coupled to the selector plate (5B) of the second restamping module (IB) and configured to supply the second restamping module. 11. Re-stamping machine according to claim 10, characterized in that the transfer conveyor (91) is coupled to a nozzle type blowing system to generate a low pressure laminar air flow, the nozzle system being positioned and configured to move, via venturi effect suction, the tips ejected by the first re-stamping module (IA) into the transfer conveyor (91) and to move, via low-pressure laminar flow thrust, the tips towards the second re-stamping module (IB).