FR3036998A1 - HIGH TONING PRESS WITH IMPROVED FASTENING - Google Patents

Abstract

The invention relates to a press (10) comprising a pressure plate (11), a counter-support base (12), at least one approach cylinder (14), at least one guide post (16) and at least one force cylinder, the guide post (16) having a rectangular section, the counter-support base (12) comprising at least one clutch (17) mounted on the counter-support base (12) rotatable about an axis (X1) between two positions: - a straight position in which the dog (17) cooperates with the guide post (16) substantially over the entire width of one side of the guide post (16) so as to maintain the bed base of against support (12) on the guide post (16), and - an inclined position in which the dog (17) does not cooperate with the guide post (16).

Description

TECHNICAL FIELD The present invention relates to a press preferably of large tonnage, that is to say whose compression force is greater than 1000 tons. The press is particularly suitable for producing composite structures that can be used to make automobile parts such as tailgates or hoods.

PRIOR ART Heavy-weight presses are generally large and have two bed bases between which a part is pressed. For example, for a heavy tonnage press of 2000 tonnes, each bed base has a dimension of 3m in length and 2.5m in width. Given the size of the parts to be produced, a large clearance is required between the two bed bases to deposit and recover the parts before and after the pressing step. For a press of large tonnage of 2000 tons, this clearance can be 3m.

In a first embodiment step, the upper beam is in an open or top dead position, remote from the support bed, and an operator or a robot has the workpiece to be pressed on a pressure plate of the bed base. The upper bed is then moved by approach cylinders in a pressing position in which the upper bed is closer to the support bed. During this first step, the movements of the upper beam are guided by circular guide columns. In a second step of carrying out the pressing, force cylinders push the pressure plate against the upper beam to press the workpiece, generally following the application of a temperature permitting the creep of a thermoformable resin impregnating the workpiece. to squeeze. During this second step, a securing device of the pressure plate on the columns must be actuated to withstand the pressure forces that the force cylinders exert on the upper bed base 3036998 2 because the approach cylinders are not sized to resume these efforts. Preferably, the securing device consists of claws movable in translation so as to grip the circular guide columns thus limiting the forces experienced by the approach cylinders.

When the pressing is completed, the force cylinders are retracted so as to release the pressed piece between the two bed bases. In this third step, the securing device is also necessary to withstand the tensile stresses of the force cylinders on the upper bed as the material of the workpiece may be sticky and generate a pull-out force which tends to maintain the upper frame secured with the pressure plate. In a final step, the upper beam is raised to the open position so that an operator or a robot can extract the pressed part and have a new part to press.

However, the support force of the jaw of the securing device on the circular columns must be very important to counter the forces applied to the upper beam by the force cylinders. In addition, the claws apply a radial force on the circular columns while the upper beam experiences a force tangential to the length of the circular columns. Thus, the pressure applied by the jaw must necessarily be very important and only a hydraulic device is compatible with the forces involved. In another type of construction, it is the force cylinders that fulfill the approach function. In this case, the use of a jaw lashing device is not necessary but this type of architecture increases the size of the jacks and the oil volumes requiring the installation of a bridge to accommodate the hydraulic equipment. Presses of this type are therefore generally of great height, for example 10 m above the ground, giving rise to access constraints in height for maintenance, assembly and transport.

The technical problem of the invention consists in providing a compact press whose system for holding in the open and pressing positions is improved.

SUMMARY OF THE INVENTION The present invention responds to this technical problem by means of a rotary clutch cooperating with a guide post of rectangular section.

To this end, the invention relates to a press comprising: a pressure plate intended to support a mold giving the geometry of a workpiece to be pressed; a support base movable in translation between two positions: an open position in which the counter-support bed is remote from the pressure plate so that an operator or a robot can intervene on the pressure plate to deposit or remove a workpiece, and - a pressing position in which the counter-support bed is closer of the pressure plate, 15 - at least one approach cylinder adapted to move the bed against against support relative to the pressure plate between the two positions, - at least one guide post adapted to guide the movements of the bed against back support between the two positions, and - at least one force cylinder adapted to move the pressure plate to the bed against 20 support when the bed against back support is in the pressing position so as to pressing a piece, - the at least one guide post having a rectangular section, - the counter-support bed with at least one dog mounted on the counter bed against rotation movable about an axis between two positions: an inclined position in which the clutch does not cooperate with the guide post, and - a straight position in which the clutch cooperates with the guide post substantially across the width of one side of the guide post so as to maintain the bed frame against pressing on the guide post in the open position and / or in the pressing position. The invention makes it possible to improve the transmission of the tangential forces applied to the bedstead of support against the posts. The rotational movement of the clutch 3036998 4 is performed around a fixed axis on the bed base which limits the force required to maintain the dog against the guide post, because the geometry of the assembly is that the application of the pressing force tends to press the dog against the post. With the invention, the movement of the clutch can be controlled by a pneumatic system thus enabling it to be freed from a gangway accommodating all the hydraulic equipment of the prior art. The invention thus reduces the size of the press. In addition, reducing the force required to maintain the dog on the pole limits the power consumption of the press compared to prior art presses because of the reduction in the stroke of the force cylinders.

According to one embodiment, the press comprises four guide posts and eight jaws able to hold the counter-support bed respectively respectively in pairs on the four guide posts in the open position and / or in the pressing position. This embodiment makes it possible to improve the support of the counter against support in the open position and / or in the pressing position. According to one embodiment, the guide post is fixed on the side of a support bed carrying the pressure plate by means of studs. In contrast to the conventional use of cylindrical posts which requires a translational mounting according to the length of the posts in bores of the support base, this embodiment makes it possible to obtain a faster assembly which requires less space to above the bed base. The mounting of the guide post can be carried out as follows: the guide post is positioned obliquely with its lower end against the support bed, then the guide post is straightened vertically against the support bed and finally, the studs are inserted to secure the guide post against the bed base. According to one embodiment, the clutch has a toothing adapted to cooperate with a rack fixed to the guide post. This embodiment also makes it possible to limit the holding force of the dog against the guide post. Advantageously, the toothing comprises teeth extending from a face of the dog intended to come opposite the rack, each tooth having an asymmetric profile 3036998 5 composed by a rounded face and a substantially flat face, the rack having a complementary profile with the teeth of the teeth. The rounded face makes it possible to maintain the bed against against support in the pressing position when the force cylinder applies a force against the bed against against support. The flat face 5 makes it possible to maintain the counter-support bed in the open position to prevent its weight from dragging it downwards, especially when an operator or a robot intervenes on the pressure plate, to deposit or remove a part. When a workpiece is pressed between the upper beam and the pressure plate, the material of the workpiece may be sticky and generate a pull-out force which tends to maintain the upper springboard integral with the pressure plate. Thus, in the pressing position, during the extraction of the pressed piece, the flat face also makes it possible to maintain the bed against against support to resist the withdrawal force of the pressure plate. The rounded face has a greater contact surface with the rack than the planar face, because the force experienced by the dog during pressing is greater than the downward pull force of the counter frame in the open position. . The specific shape of the teeth thus makes it possible to respond effectively to these two opposing forces and unequal amplitudes acting on the clutch. Advantageously, the upper end of the guide post has a shoulder, the toothing being able to cooperate with the shoulder. This embodiment makes it possible to improve the retention of the counter-support bed in the open position. According to one embodiment, the press comprises a clamping cylinder adapted to control the movements of the clutch between the two positions of the dog. This embodiment makes it possible to limit the forces required to press the dog against the rack, and thus to block the springboard against translational support on the guide post. Advantageously, the clamping cylinder is connected to the dog by means of a toggle joint comprising: a first link mounted on the counter base movable in rotation about a lateral axis, and a second mounted link on the rotating clutch rotating about a lateral axis, the links being connected at a central axis by a pivot connection, the movements of the central axis being guided in displacement by the clamping cylinder between the two positions: - the straight position in which the central axis is disposed above a line connecting the two lateral axes against a stop, and - the inclined position in which the central axis is disposed below a line connecting the two lateral axes.

This embodiment makes it possible to lock the dog in the upright position so that the force applied on the clutch is transmitted to the stop. Thus, if the clamping cylinder has a failure and it no longer ensures the maintenance of the clutch, the clutch remains in the upright position and the back support spring remains fixed. This embodiment is particularly advantageous in the open position to avoid the risk of descent of the counter bed against support when an operator or a robot intervenes on the pressure plate. SUMMARY DESCRIPTION OF THE FIGURES The manner of carrying out the invention as well as the advantages which result therefrom will clearly emerge from the following embodiment, given as an indication but without being limiting, in support of the appended figures in which FIGS. 13 show: - Figure 1: a schematic perspective front view of a press 25 according to one embodiment of the invention in a pressing position; - Figure 2: a schematic perspective view from below the press of Figure 1 in an open position; 3: a diagrammatic front perspective view of the press of FIG. 1 in an open position without representation of the decking of the pit; - Figure 4: a schematic perspective front view of a first step of mounting the press of Figure 1; FIG. 5 is a diagrammatic front perspective representation of a second assembly step of the press of FIG. 1; - Figure 6: a schematic perspective front view of a third mounting step of the press of Figure 1; Figure 7 is a diagrammatic perspective view of a fourth assembly step of the press of Figure 1; - Figure 8: a schematic perspective front view of a fifth assembly step of the press of Figure 1; - Figure 9: a schematic perspective side view of a sixth assembly step of the press of Figure 1; 10 - Figure 10: an exploded perspective view from the front of the press of Figure 1 in a pressing position; - Figure 11: an exploded view in front perspective of the press of Figure 1 in an open position; 12: a perspective representation of a clutch of the press of FIG. 1; and FIG. 13 is a diagrammatic representation of the gear teeth of FIG. 12. DETAILED DESCRIPTION OF THE INVENTION FIGS. 1 to 3 illustrate a press 10 comprising a pressure plate 11 and a counter-support springboard. 11 is movable in translation relative to a fixed support bed 15. The counter-support base 12 is also movable in translation between two positions: an open position Pm, illustrated in FIGS. 2 and 3, and a pressing position Pp, illustrated in FIG. 1. The open position Pm serves for the change of position. a pressing mold, loading the material to be pressed, unloading a part and maintenance. The pressing position Pp is used to press the material into the mold.

The displacements of the backstop bed 12 between the two positions Pm, Pp are guided by four posts 16 under the effect of four approach cylinders 14. When the backstop bed 12 is in the pressing position Pp, the pressure plate 11 is pressed against the counter-support bed 12 by force cylinders. Preferably, the force cylinders provide in a conventional manner a parallelism of the position of the pressure plate 11 relative to the counter-support bed 12 by adjustment of the applied pressure. For example, the press 10 comprises four force cylinders making it possible to apply a force guaranteeing a parallelism of the pressure plate 11 with respect to the counter-support base 12 by compensating the eccentricity of the force related to the geometry of the part . Each guide post 16 extends over a height of between 4 and 7 m and has a rectangular section. Means of cooperation are arranged between each guide post 16 and the counter-support bed 12 allowing rapid movement of the counter-support bed 12 between the open position Pm and the pressing position Pp. As illustrated in FIG. 9 each guide post 16 is fixed on the support bed 15. Preferably, the pressure plate 11 is mounted on a support bed 15 arranged in a pit so that an upper face of the pressure plate 11 is extends substantially to ground level. For example, the pit has a depth of about 2.5m. As illustrated in FIGS. 4 to 9, the mounting of each guide post 16 is preferentially carried out in the following manner: the guide post 16 is positioned at an angle with its lower end against the support bed 15, and then the guide post 16 is straightened vertically against the support bed 15 and, finally, about ten studs 19 are inserted to secure the guide post 16 against the support bed 15.

In the pressing position Pp, each rack 21 cooperates with a clutch 17 rotatably mounted on the counter-bearing base 12. In the open position Pm, each clutch 17 cooperates with a shoulder 46 formed on an upper end 45 of the post. 16. To cooperate with the rack 21 or the shoulder 46, each dog 17 is rotatable about an axis X1 between two positions: an inclined position Pi in which the dog 17 is not in contact with the dog. post 16 and a straight position Pd in which the clutch 17 is in contact with the rack 21 or the shoulder 46 so as to maintain the counter-support bed 12 on the post 16. FIG. 10 illustrates two jaws 17 in the inclined positions Pi and 3036998 9 right Pd in the pressing position Pp. Figure 11 illustrates two jaws 17 in the inclined positions Pi and right Pd in the open position Pm. The movements of each clutch 17 between the inclined positions Pi and Pd right 5 are provided by a clamping cylinder 30. To do this, a lower portion of the clutch 17 is rotatably mounted on the axis X1 and an upper portion of the clutch 17 is displaced by a toggle joint 31. As shown in FIG. 12, the toggle joint comprises two links 32, 33 forming a hinge whose central point, the central axis X 4, is displaced by the clamping cylinder 30. rod 32 comprises a first end mounted on the counter-support bed 12 rotatable on a lateral axis X2 and a second end rotatably mounted on the central axis X4. The second link 33 has a first end mounted on the upper part of the clutch 17 rotatable on a lateral axis X3 and a second end rotatably mounted on the central axis X4.

When the dog 17 is in the inclined position Pi, the clamping cylinder 30 is retracted and the central axis X4 is disposed below a line connecting the two lateral axes X2, X3. When the dog 17 is in the right position Pd, the clamping cylinder 30 is extended and the central axis X4 is disposed above a line connecting the two lateral axes X2, X3 against a stop 35. The stop 35 is particularly advantageous because it supports the forces applied to the clutch 17 in the right position Pd. The clamping cylinder 30 can thus have a failure without the clutch 17 leaving the right position Pd.

The cooperation of the clutch 17 with the rack 21 or the shoulder 46 is also provided by a toothing 20 disposed on a face 25 of the clutch 17. When the dog 17 is in the right position Pd and cooperates with the rack 21, teeth 22 of the toothing 20 penetrate recesses of complementary shape of the rack 21. When the clutch 17 is in the straight position Pd and cooperates with the shoulder 46, a tooth 22 of the toothing 20 rests on the shoulder 46. FIG. 13 illustrates the profile of the toothing 20 of the clutch 17 having a rounded face 23 and a flat face 24. The rounded face 23 makes it possible to maintain the counter-support bed 12 in the pressing position Pp when the force ram applies a force against the 3036998 10 bed against back support 12. The flat face 24 keeps the counter bed against support 12 in the open position Pm to prevent its weight from causing it downwards especially when an operation ur or a robot intervenes on the pressure plate 11 to remove or remove a part. When a piece is pressed between the upper bed base 12 and the pressure plate 11, the material of the piece can be tacky and generate a force of tear resistance which tends to maintain the upper bed base 12 integral with the pressure plate 11 Thus, in the pressing position Pp, during the extraction of the press piece, the flat face 24 also makes it possible to hold the counter-support bed 12 to resist the withdrawal force of the pressing plate 11. The rounded face 23 10 has a contact surface with the rack 21 greater than the flat face 24 because the force experienced by the clutch 17 during the pressing is greater than the downward pull force of the counter frame support 12 in the open position Pm. The specific shape of the toothing 20 thus makes it possible to respond effectively to these two opposing forces acting on the clutch 17.

The press 10 is illustrated in FIGS. 1 to 13 for vertical mounting with the counterbase 12 on the presser plate 11 so as to use the force of gravity to help maintain the counterbase 12 during pressing. and to limit the forces on the dogs 17. In a variant, the invention can also be implemented with a horizontal press. The invention makes it possible, in the compression phases, to improve the connection between the backstop bed 12 and the guide post 16 and thus to ensure good recovery of the forces. It also saves energy, saves space and avoids the use of hydraulic system potentially source of pollution. The invention also ensures locking jaw 17 by the links 32, 33. This is particularly advantageous when the press 10 is in the open position Pm, position used for maintenance, thus protecting people acting under the bed against support 12 in In practice, the press 10 makes it possible to press a composite or metal part with a force greater than 1000 tonnes and a thickness tolerance of less than 501.1m. Alternatively, the features of the press 10 may also be used in smaller presses without changing the invention.

Claims (8)

REVENDICATIONS1. Press (10) comprising: - a pressure plate (11) intended to support a mold giving the geometry of a part to be pressed, - a counter-support spring (12) movable in translation between two positions (Pm, Pp): an open position (Pm) in which the counter-support bed (12) is remote from the presser plate (11) so that an operator or a robot can intervene on the pressure plate (11) to deposit or remove a workpiece, and a pressing position (Pp) in which the counter-support spring (12) is closer to the pressure plate (11); at least one approach cylinder (14) able to move the counter-support spring (12) relative to the pressure plate (11) between the two positions (Pm, Pp), - at least one guide post (16) adapted to guide the movements of the counter-support bed (12) between the two positions (Pm, Pp) , and - at least one force cylinder capable of moving the pressure plate (11) towards the counter-support spring (12) when the spring against the support (12) is in the pressing position (Pp) so as to press a part, characterized in that: - the at least one guide post (16) has a rectangular section, and in that - the counter-support base (12) comprises at least one clutch (17) mounted on the counter-support base (12) movable in rotation about an axis (X1) between two positions (Pi, Pd): an inclined position (Pi) in which the dog (17) does not cooperate with the guide post (16), and - a straight position (Pd) in which the clutch (17) cooperates with the guide post (16) substantially over the entire width of one side of the guide post (16) so as to maintain the counter-support bed (12) on the guide post (16) in the open position (Pm) and / or in the pressing position (Pp) ). 3036998 12 2. Hydraulic press according to claim 1, characterized in that it comprises four guide posts (16) and eight jaws (17) able to maintain the bed against support (12) respectively two by two on the four guide posts (16) in the open position (Pm) and / or in the pressing position (Pp). 5 3. Hydraulic press according to claim 1 or 2, characterized in that the guide post (16) is fixed on the side of a support bed (15) carrying the pressure plate (11) by means of studs (19). ). 10 4. Hydraulic press according to one of claims 1 to 3, characterized in that the clutch (17) has a toothing (20) adapted to cooperate with a rack (21) fixed on the guide post (16). 5. Hydraulic press according to claim 4, characterized in that the toothing (20) comprises teeth (22) extending from a face (25) of the dog intended to come opposite the rack (21), each tooth (22) having an asymmetric profile composed of a rounded face (23) and a flat face (24), the rack (21) having a complementary profile with the teeth (22) of the toothing (20). 20 6. Hydraulic press according to claim 4 or 5, characterized in that the upper end (45) of the guide post (16) has a shoulder (46), the toothing (20) being adapted to cooperate with the shoulder ( 46). 7. Hydraulic press according to one of claims 1 to 6, characterized in that it comprises a clamping cylinder (30) adapted to control the movements of the clutch (17) between the two positions (Pi, Pd) of the clutch (17). 8. Hydraulic press according to claim 7, characterized in that the clamping cylinder (30) is connected to the dog (17) via a toggle (31) 30 comprising: - a first link (32) mounted on the counter-support base (12) rotatable about a lateral axis (X2), and 3036998 13 - a second link (33) mounted on the clutch (17) rotatable about a lateral axis (X3) the links (32, 33) being connected at a central axis (X4) by a pivot connection, the displacements of the central axis (X4) being guided in displacement by the clamping cylinder (30). between the two positions (Pi, Pd): - the straight position (Pd) in which the central axis (X4) is disposed above a line connecting the two lateral axes (X2, X3) against a stop (35); ), and the inclined position (Pi) in which the central axis (X4) is disposed below a line connecting the two lateral axes (X2, X3).