PRESS FOR THE DIRECT EXTRUSION OF METALLIC MATERIAL

Abstract

The present invention relates to a press for the direct extrusion of metallic material, wherein the press comprises a supporting structure which defines an extrusion axis and a transverse direction orthogonal to said extrusion axis. The press further comprises an extrusion die and a die-holder drawer, in which said die is placed. Moving means are provided for moving said drawer along a transverse direction between a first position (P1), in which said die is aligned with said extrusion axis, and a second position in which, when reached, said die can be replaced. The press according to the invention further comprises a fixed supporting element which supports the drawer at least when it occupies the first position. The press further comprises at least a movable supporting element for supporting said drawer during the movement along said transverse direction; lifting means are provided for vertically lifting the movable supporting element between a first vertical position, in which the drawer is supported by the fixed supporting element, and a second vertical position, in which the drawer is lifted with respect to the fixed supporting element and supported by said at least one movable supporting element.

Claims

1) A press for the direct extrusion of metallic material, wherein said press comprises: a supporting structure which defines an extrusion axis of said metallic material and a transverse direction orthogonal to a vertical plane containing said extrusion axis; an extrusion die; a die-holder drawer in which said die is placed; moving means for moving said drawer along a transverse direction between a first position (P1), in which said die is aligned with said extrusion axis, and a second position in, which, when reached, said die can be replaced; a fixed supporting element which supports said drawer at least when it occupies said first position (P1), characterized in that it comprises: at least a movable supporting element for supporting said drawer during the movement along said transverse direction; lifting means for vertically lifting said at least one movable supporting element between a first vertical position (V1), in which said drawer is supported by said fixed supporting element, and a second vertical position, in which said drawer is lifted with respect to said fixed supporting element and supported by said at least one movable supporting element.

2) The press according to claim 1, wherein said press comprises a plurality of movable supporting elements for supporting said drawer during its movement along said transverse direction, wherein said lifting means lift each of said movable supporting elements between said vertical positions (V1,V2).

3) The press according to claim 2, wherein said press comprises a first movable supporting element and a second movable supporting element arranged on opposite sides with respect to said fixed supporting element.

4) The press according to claim 3, wherein said fixed supporting element comprises a transverse guide portion defining an abutment surface which extends on a plane substantially orthogonal to said extrusion direction.

5) The press according to claim 4, wherein said fixed supporting member comprises at least one resting surface on which said drawer rests and wherein said at least one movable support comprises at least one sliding surface on which said drawer slides during its movement along said transverse direction.

6) The press according to claim 4, wherein said first resting surface and/or said, sliding surface is made of bronze.

7) The press according to claim 5, wherein said fixed supporting element comprises a body made of metallic material and a plate made of metallic material fixed to said body, wherein said plate defines said resting surface.

8) The press according to claim 7, wherein said at least a movable supporting element comprises a body made of metallic material and a plate fixed to said is body, wherein said plate defines said sliding surface.

9) The press according to claim 8, wherein a shim is interposed between said plate and said body.

10) The press according to claim 1, wherein said lifting means comprise one or more hydraulic actuators.

11) The press according to claim 1, wherein said press comprises locking means for stably locking said drawer in said first position (P1), wherein said locking means are configured to prevent vertical displacements of said extrusion die in said drawer.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0024] Further features and advantages of the present invention will be apparent in light of the detailed description of preferred, but not exclusive, embodiments of a press for the extrusion of metallic material according to the present invention as illustrated by way of non-limiting example, with reference to the accompanying drawings, in which:

[0025] FIG. 1 is a view of a press of known type;

[0026] FIG. 2 is a section view taken along section plane II-II in FIG. 1;

[0027] FIG. 3 is a partial cross-section, detail view of some components of the press in FIG. 1;

[0028] FIG. 4 is a view of a press according to the invention;

[0029] FIG. 5 is a section view taken along line V-V in FIG. 4;

[0030] FIGS. 6 and 7 are partial cross-section side views of the press in FIG. 4 in two different first operating configurations;

[0031] FIG. 7 is a partial cross-section side view of the press in FIG. 4 in a second operating configuration;

[0032] In Figures from 4 to 7, the same reference numerals and letters are used to identify the same elements or components.

DETAILED DESCRIPTION OF THE INVENTION

[0033] With reference to FIGS. 4 to 7, the present invention relates to a press (generically indicated by reference numeral 1) for the extrusion of metallic material, particularly but not exclusively for the extrusion, of aluminum. The press 1 comprises a supporting structure 10, which defines an extrusion direction 500 along which the metal material is extruded through a die 2. According to a principle known in itself, the die 2 confers the shape of the section of the metal profile generated by the extrusion.

[0034] The supporting structure 10 has a configuration known in itself comprising a first crosspiece 13, near which an extrusion die 2 is placed (hereinafter also referred to as die 2), and a second crosspiece 14 in a position distanced from said die 2. The two is crosspieces 13, 14 are connected by columns 18 which develop in parallel defining the extrusion direction 500. With particular reference to FIG. 4, the press 1 comprises a thrust cylinder 200, integral to the, second crosspiece 14, which generates the force necessary to extrude the material. In particular, the cylinder 200 moves a rod 210 provided, at its free end, with a punch 240 which acts on the material to be extruded, according to a widely known principle.

[0035] The press 1 comprises a container 5 inside which the metal material to be extruded is loaded. Preferably, the container is defined by a cylindrical hollow body which contains the billet in a plastic state. The container 5 is supported by a container holder 6 which rests on a plurality of pads 11, preferably two. These pads 11 slide along corresponding guides 12 fixed to the supporting structure 10 and parallel to the extrusion direction 500. Therefore, the container-holder 6 also slides parallel to the extrusion direction 500. In this regard, appropriate thrust cylinders 250 are provided to allow the movement of the container-holder along the extrusion direction 500.

[0036] The press 1 according to the invention comprises a die-holder drawer 20 (hereinafter also referred to as drawer 20) in which the die 2 is placed. The drawer 20 is movable along a transverse direction 600 between at least a first and a second position (identified by P1 and P2 in FIG. 5). For the purposes of the present invention, the expression transverse direction 600 means a direction substantially orthogonal to a vertical plane containing the extrusion axis 500. In the first position P1, the die 2 is aligned with the extrusion axis 500, i.e. in such a condition that the extrusion operation can be started. On the other hand, the second position P2 is set so that the die 2 can be easily extracted and replaced. Preferably, the second position. P2 is such that the drawer 20 is substantially outside the volume delimited by columns 33 of the supporting structure 10 (condition shown in the right part of FIG. 5).

[0037] The drawer 20 is moved along the transverse direction 600 using moving means 4. Preferably, the latter comprises an actuator 4B which moves a rod 4C connected, either directly or indirectly, to the drawer 20 so that a displacement of the rod 4C results in a corresponding displacement of the drawer 20.

[0038] The press 1 according to the invention further comprises at least one fixed supporting element 30 which supports the drawer 20 at least when it occupies the first position P1 indicated above. In particular, the fixed supporting element 30 comprises a resting surface 31 for the drawer 20. In accordance with an embodiment depicted in the figures, the fixed supporting element 30 comprises a metallic material body 34 connected to the front crosspiece 13 by means of appropriate fixing means 39 (shown in FIG. 6). The fixed supporting element 30 further comprises a plate 31B, preferably made of bronze, which is fixed to the body 34 and which defines the supporting surface 31.

[0039] The press 1 according to the invention further comprises at least one movable supporting element 40,50 which supports the drawer 20 during the movement along the transverse direction 600. Said at least one movable supporting element 40,50 comprises a body 44,54 to which a plate 41B,51B made of metallic material, preferably bronze, is fixed. Such a plate 41B,51B defines a sliding surface 41,51 for the drawer 20.

[0040] The press 1 according to the invention comprises lifting means 70 for lifting the movable supporting element 40,50 between a first and a second position (indicated respectively by V1 and V2 in FIGS. 6 and 7), wherein said positions are determined according to a vertical direction, i.e. orthogonal to the extrusion axis 500 and to the transverse direction 600. In particular, the first position V1 (hereinafter also the first vertical position V1) is such that the drawer 20 is supported only by the fixed supporting element 30 and in particular on the supporting surface 31. The latter basically determines the vertical position of the drawer 30 and thus of the die 2 housed therein. Therefore, the contact surface 31 of the fixed supporting element 30 establishes the alignment condition of the die 2 with the extrusion axis 500.

[0041] The second position V2 (hereinafter also indicated as second vertical position V2) is such that the drawer 20 is only supported by the movable supporting element 40,50 and therefore no longer rests on the supporting surface 31 of the fixed supporting element 30. Basically, when the second vertical position V2 is reached, the drawer 20 is raised in relation to the fixed supporting element 30. As described in greater detail below, according to the invention, the transverse movement 800 of the drawer 20 is achieved precisely when the movable supporting element 40,50 occupies the second position V2. In this manner, the drawer 20 slides only on the sliding surface 41B,51B of the mobile supporting element 40,50 without concerning the supporting surface 31 of the fixed supporting element 30. This solution thus limits wear of the contact surface 31 and considerably increases its service life.

[0042] According to a preferred embodiment, shown in particular in FIGS. 6 and 7, the press 1 comprises a first movable supporting element 40 and a second movable supporting element 50 having precisely the function of supporting the drawer 20 during its movement along the transverse direction 200. Preferably, the two movable supporting elements 40,50 are arranged on opposite sides of the fixed supporting element 30. Preferably, the two movable supporting elements 40,50 both have the configuration described above defined by a body 44,54 and a plate 41B,51B made of metallic material, preferably bronze, fixed to the body 44,54 and which defines a corresponding sliding surface 41B,51B for the drawer 20.

[0043] According to a possible embodiment, for one or both movable elements 40,50, a shim 47,57 may be placed between the corresponding body 44,54 and the corresponding plate 41B,51B. In any case, these shims 47,57 do not require frequent replacement because they do not contribute to the alignment of the die 2 with extrusion axis 500.

[0044] According to a possible embodiment shown in the figures, the lifting means comprises a number of hydraulic actuators 70 configured so as to provide a sufficient force to lift the movable supporting elements 40,50 and the drawer 20 which runs along them. According to an alternative embodiment, the hydraulic actuators 70 could be replaced by electric or even by pneumatic actuators.

[0045] According to another aspect, the fixed supporting element 30 comprises a guide portion 33 defining a transverse guide 33B which extends on a plane which is substantially orthogonal to the extrusion axis 500. This transverse surface 33B establishes a guide for the movement of the drawer 20 and allows the drawer itself to move stably along the transverse direction 600. At the same time, the transverse surface 33B defines the position of the drawer 20 along the extrusion axis 500.

[0046] FIGS. 6 and 7 show the basic moving principle of the drawer 20 along a transverse direction. During the normal operation of the press 1, i.e. during the step of extruding of the metal material, the drawer 20 is placed only on the supporting surface 31 of the fixed supporting element (condition in FIG. 6). In this condition, the two movable supporting elements 40,50 are placed in the first vertical position V1 and do not offer any support to the drawer 20. The die 2 is aligned with extrusion axis 500 as a result of the height established by the support surface 31 of the fixed supporting element 30.

[0047] When the die 2 must be replaced, the lifting means 70 are activated to take the supporting moving parts 40,50 to the second vertical position V2. During their movement towards the second vertical position V2, the two movable supporting elements 40,50 lift the drawer 20 with respect to the supporting surface 31 of the first supporting element 30. In this manner, the supporting surface 31 remains free and is not concerned by the subsequent movement of the drawer 20 (condition shown in FIG. 7).

[0048] Once the two movable supporting elements 40,50 have reached the second vertical position V2, the moving means 4 are activated to push the drawer 20 from the working position (first position P1) to the die change position (second position P2). Therefore, during this step, the drawer 20 slides only along the sliding surfaces 41,51 of the two moving, support elements 40,50. Thus, during the transverse movement of drawer 20, there is no contact between the drawer 20 and the contact surface 31 of the fixed supporting element 30. The integrity of such supporting surface 31 is so preserved for the benefit of greater durability.

[0049] According to another aspect, the press 1 according to the invention further comprises to locking means to stably lock the drawer 20 in the first predetermined position P1. More precisely, these locking means act on the die 2 to counteract the vertical movements which may be induced on the die itself following due to the action exerted by the shear at the end of the extrusion of the billet and before the extrusion of the next one.

[0050] In an embodiment shown in FIG. 5, such locking means comprise a first wedge-shaped element 81 attached to the front crosspiece 13 on the side which faces the die 2. The locking means further comprise a second wedge-shaped element 82 which is movable along the transverse direction 600 through the action of an actuator 85, e.g. of the hydraulic type. The two elements 81,82 each comprise an inclined surface which confers wedge shape to them.

[0051] The two elements 81,82 are operationally coupled by means of their inclined surfaces so that the second element 82 slides with respect to the first element 81. A portion of the second element 82 comes into contacts with the top of the die 2. As a result of such a coupling, following the displacement along the transverse direction 800 in a predetermined direction (leftwards in the solution shown in FIG. 5), the second element 82 applies vertical pressure on the die 2, forcing it against the supporting surface 31 of the fixed supporting element 30. In this manner, movements which could be induced by the movement of the shear in contact with the surface of the die are avoided, especially during the upward step of the shear, are avoided.

[0052] Although the present invention is explained above by means of a detailed description of the embodiments thereof shown in the drawings, the present invention is obviously not limited to the embodiments described above and shown on the drawings. On the contrary, all the modifications and/or variants of the embodiments described above and shown in the drawings which will appear obvious and immediate to a person skilled in the art are included in the scope of the present invention.