Abstract
A bar and tube extruding press for thrilling metal ingots into profiles, tubes, bars or the like includes a male die and a female die, through which a metal ingot can be pressed by the male die a container, and a driving device, in which the driving device has at least one main cylinder tor applying the main pressing force of the male die to the metal ingots, characterized in that on the one hand the driving device having at least one speed-controlled internal gear pump for providing the hydraulic oil to the at least one main cylinder, with which the at least one main cylinder can be driven, and at least one hydraulic advance and/or return cylinder for moving the male die in relation to the female die or at least one electrical drive for moving the male die in relation to the female die and with which the male die can be moved into a position in which the speed-controlled internal gear pump only then interacts with the at least one main cylinder in such a way that the main pressing force is applied to the male die by the at least one main cylinder.
Claims
1. A bar and tube extruding press for forming metal ingots into profiles, tubes, billets, or the like, comprising a male die and a female die, through which a metal ingot can be pressed by means of the male die, comprising a ingot container, and comprising a driving device, in which the driving device comprises at least one main cylinder for applying the main pressing force of the male die to the metal ingots, characterized in that the driving device on the one hand includes at least one speed-controlled internal gear pump for supplying hydraulic oil to the at least one main cylinder with which the at least one cylinder can be driven, and on the other hand the driving device additionally comprises at least one hydraulic advance and/or return cylinder for moving the male die in relation to the female die or at least one electrical drive for moving the male die in relation to the female die, by means of which the male die can be moved into a position in which the speed-controlled internal gear pump only then interacts with the at least one main cylinder in such a way that the main pressing three is applied to the male die by means of the at least one main cylinder.
2. The bar and tube extruding press according to claim 1, characterized in that the driving device includes means for moving the male die and/or the ingot container and/or the female die and means for applying a pressing three between the female die and the male die.
3. The bar and tube extruding press according to claim 1, characterized in that the at least one electric drive preferably is an electric servo drive for moving the male die in relation to the female die.
4. The bar and tube extruding press according to claim 1, characterized in that the internal gear pump can be driven using mixed friction from startup until the desired system pressure is reached.
5. The bar and tube extruding press according to claim 1, characterized in that the driving device is connected to a control unit in which a characteristic curve or a plurality of characteristic curves for the internal gear pump and/or its drive motor(s) is/are stored.
6. The bar and tube extruding press according to claim 1, characterized in that the pulsation of the internal gear pump, particularly the preferred internal gear pump, is lower than in axial piston pumps, preferably by at least 20%, preferably by at least 30%, compared to the pulsation of conventional axial piston pumps.
7. A method of forming metal ingots into profiles, tubes, billets, and the like on a bar and tube extruding press having an ingot container, a male die and female die through which a metal ingot is pressed by the male die, a driving device including at least one main cylinder, at least one speed-controlled internal gear pump for supplying oil to the at least one main cylinder, at least one speed-controlled internal gear pump for supplying oil to the at least one main cylinder, and one of the at least one hydraulic advance/return cylinder and at least one electrical drive tor moving the male die relative the female die, the method comprising the steps of: actuating the one of the at least one hydraulic advance/return cylinder and the at least one electrical drive for moving the male die is a predetermined position relative to the female die; and thereafter, actuating the at least one speed-controlled internal gear pump for supplying oil to the at least one main cylinder that applies a main pressing force to the mail die for pressing the ingot through the male and female dies.
8. The method of claim 7, wherein the at least one electrical drive is used for moving the mail die, and the method further comprising the step of forming the electrical drive as an electric servo drive.
9. The method of claim 7, comprising the step of driving the speed-controlled internal gear pump using mixed friction from startup until a desired system pressure is reached.
10. The method of claim 7, comprising the step of selecting pulsation of the speed-controlled internal gear pump so that it is lower than pulsation of a conventional axial piston pump by at least 20%.
11. The method of claim 10, wherein the pulsation selecting step includes selection of the pulsation of the speed-controlled internal gear pump which is lower than the pulsation of the conventional gear pump by at least 30%.
Description
DESCRIPTION OF THE DRAWINGS
[0055] Further details and characteristics of the invention derive from the claims and the following description of exemplary embodiments,
[0056] FIG. 1 shows in perspectival view, as a detail of a bar and tube extruding press or of a metal extrusion press, its press frame with a male die traverse and an ingot container holder arranged in it;
[0057] FIG. 2 shows the rearward part of the press from FIG. 1, including the cylinder housing of the main or press cylinder and the male die traverse with electric motors and toothed racks, in a partially sectioned top view;
[0058] FIG. 3 shows a top view according to FIG. 2, but contrastingly, for ingot upsetting, with activated clamping device;
[0059] FIG. 4 shows a top view according to FIG. 2, but contrastingly, shown with a filler valve closed for pressing;
[0060] FIG. 5 shows as a detail of FIGS. 2 through 4, a cross section of the filler valve adjustable by a cylindrical ring, integrated in the cylinder housing;
[0061] FIG. 6 shows as a detail of FIGS. 2 through 4, as a cross section, an embodiment of a clamping device in a non-activated position;
[0062] FIG. 7 shows the clamping device from FIG. 6 in an activated position;
[0063] FIG. 8a, b show in a schematic side view (FIG. 8a) and top view (FIG. 8b) the press from FIG. 1 in its ingot loading position;
[0064] FIG. 9a, b show in a schematic side view (FIG. 9a) and top view (FIG. 9b) the press in its operating position for clamping a loaded ingot to be pressed;
[0065] FIG. 10a, b show in a schematic side view (FIG. 10a) and top view (FIG. 10b) the press in its operating position with an ingot container holder moved forward above the ingot to be pressed;
[0066] FIG. 11a, b show in a schematic side view (FIG. 11a) and top view (FIG. 11b) the press in its operating position for pre-compressing the ingot;
[0067] FIG. 12a, b show in a schematic side view (FIG. 12a) and top view (FIG. 12b) the operating position for pressing the ingot until a certain remaining extrusion butt length;
[0068] FIG. 13a, b show in a schematic side view (FIG. 13a) and top view (FIG. 13b) the operating position after the stripping of the remaining extrusion butt; and
[0069] FIG. 14a, b show in a schematic side view (FIG. 14a) and top view (FIG. 14b) the press having moved back into its ingot loading position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0070] Of a bar and tube extruding press or a metal extrusion press 1, FIG. 1 essentially shows a base frame. This consists of a cylinder bar 2 and a counter bar 4, not displayed here, which is braced to it by way of traction sipes 3 (cf. for instance, FIG. 8a). Further contributing to the frictional connection between these components are pressure columns 5, which envelop the traction sipes 3 between the cylinder bar 2 and the counter bar 4. The pressure columns 5 also serve as guide supports of a male die traverse 6 which is movable in the base frame, and of a movable ingot container holder 7. The ingot container holder 7, which holds an ingot container or recipient 8, is moved by way of electric motors 12 or 13, specifically of servo drives, like the male die traverse 6, which supports the advance end of a press piston 11 guided with hydrostatic bearings in its cylinder housing 9 in the counter bar 4 (cf. FIGS. 2 through 4). Such an electric motor 12 or 13 is provided on each longitudinal side of the ingot container holder 7 and the male die traverse 6. For the transmission or initiation of the movement, pinions of the electric motors 12 or 13 comb with toothed racks 14. Screwed onto the rear end of the cylinder housing 9 of the cylinder bar 2 is a compensation tank 15, and screwed onto the rear wall 16 of the compensation tank 15 is a cylinder unit 17. In order to upset and press an ingot 18 loaded into the ingot container 8, the press piston 11 has an extrusion die 19.
[0071] As shown in FIGS. 2 through 4, integrated into the cylinder housing 9 of the main or press cylinder is embodied a central filler valve 20, which consists of a large-scale valve cover 21 and a cylindrical ring 22 for operating the filler valve. In the exemplary embodiment, the tiller valve 20, which is shown more closely in FIG. 5, is positioned on an outer tube 23 connected to the rearward end of the press piston 11, interposed by a collar-shaped displacement sleeve 24, on which the cylindrical ring 22 is positioned as well. When applying hydraulic oil to the rearward end of the cylinder piston 25 of the cylindrical ring 22 in FIG. 5, the displacement sleeve 24, and therefore the filler valve cover 21, is moved out of its closing position, indicated by solid lines, and into the opening position, indicated by dashed lines, in which the filler valve cover 21 enters into a contour adjusted [sic] recess 26 of the press piston 11. In the opening position, a large and free flow cross-section or ring area is available, through which the hydraulic oil can flow from the compensation tank 15 to the pressure chamber of the cylinder housing 9 behind the press piston 11and vice versawithout much resistance. In order to draw back the filler valve cover 21 into the closing position, the cylindrical ring 22 is switched over, so that hydraulic oil is brought before the cylinder piston 25 via the pressure oil lines, upon which the displacement sleeve 24 with the filler valve cover 21 is withdrawn correspondingly.
[0072] In this case, the outer tube 23 carrying the cylindrical ring 22 with the filler valve cover 21 is part of a rod assembly 27, which reaches into the compensation tank 15 and which features a slide plate 28 at that end, which, when the press piston 11 is charged, moves the hydraulic oil via the open filler valve cover 28, of which FIGS. 2 and 3 show the opening position, in the direction of the pressure according to arrow 29 into the pressure chamber behind the press piston 11, or when the filler valve cover 21 is closed for pressurizing as shown in FIG. 4, into a tank provided adjacent to the press, as shown by the downward arrow. The rod assembly 27 comprises a pressure bar 31 reaching into the outer tube 23, which is in an operative connection with the cylinder unit 17 which is flange-mounted onto the rearward end or onto the rear wall 16 of the compensation tank 15. The free end of the pressure bar 31 features a clamping device 32, via which the pressure bar 31 can be pressed from the inside against the outer tube 23 to [form] a rigid motion unit with it, when necessary, as in the mode of operation of the bar extruding press 1 for ingot upsetting shown in FIG. 3. The clamping device 32 is activated by the combined cylinder unit 17 due to the corresponding charge of its first coolant path 33.
[0073] In an embodiment of the clamping device 32 shown in FIGS. 6 and 7, it features a central spline 34 screwed onto the pressure bar 31, and its associated complementary keys 35a, 35b. When the clamping device 32 is not activated (cf. FIG. 6), the central spline 34 in the drawing left is moved out forward. When the clamping device 32 is then activated via the cylinder unit 17 (cf. FIG. 7), the spline 34 is pulled by the cylinder unit 17 to the right in the drawing, such that the complementary keys 35a, 35b press against the inner walls of the outer tube 23.
[0074] The combined electromotive and hydraulic operation of the bar and tube extruding press 1 will be described in further detail below with reference to FIGS. 8a, 8b through 14a, 14b. FIGS. 8a, and 8b show the ingot loading position, in which the ingot 18 to be pressed is brought into the center of the bar and tube extruding press 1 with a typical ingot loading device. As can be more clearly seen there, the bar and tube extruding press 1, apart from the previously described components, also comprises tow rods 36 on each side of ingot container holder 7, preferably on each side at the top and at the bottom, of which the free ends are guided through the cylinder bar 2 with freedom of movement (cf. also FIG. 1). The tow rods 36 are assigned to combined cylindrical ring and clamping units 37 that are attached the cylinder bar 2, in the ingot loading position, all moving parts are in the starting position, away from the counter bar 4.
[0075] The ingot container holder 7 and the male die traverse 6 with the press piston 11 and the extrusion die 19 are moved forward in the pressure direction 29 with an opened filler valve 20 (cf. FIG. 2) by means of the electric motors 12, 13 to the clamps shown in FIGS. 9a and 9b of the loaded ingot 18 between the extrusion die 19 and the tool or tool set 38 of the counter bar 4, with a first quantity of hydraulic oil being moved out of the compensation tank 15 into the pressure chamber behind the press piston 11. The ingot 18, which is now clamped, is moved into the ingot container 8 by moving forward the ingot container holder 7 by means of the electric motors 13, as shown in FIGS. 10a, 10b, with the tow rods 36 pulled along when the cylindrical rings and clamping units 37 are not activated, In order to seal the ingot container 8 against the tool set 37 [sic], the cylindrical rings and clamping units 37 are now activated, and the ingot container holder 7 or the ingot container 8 are moved by it against the tool 37.
[0076] FIGS. 11a, 11b show the resulting pressing or pre-compressing of the ingot 18, With the electric motors 12, 13 switched off, the combined cylinder unit 17 is loaded and the clamping device 32 is activated, so that the pressure bar 31 is pressed against the outer tube 23. Subsequently, the cylinder unit 17 transfers the pressure force onto the press piston 11 via the rigid rod assembly 27, consisting of the pressure bar 31 and the outer tube 23. A second partial quantity of hydraulic oil is moved out into the pressure chamber behind the press piston 11, as the filler valve is open in this pressure position as well (cf. FIG. 3). The subsequent pressing of the ingot to a remaining extrusion butt 39 is shown in FIGS. 12a and 12b. The clamping device 32 is deactivated for pressing, and the filler valve cover 21 of the integrated filler valve 20 is withdrawn into its closing position shown in FIG. 4 by means of the cylindrical ring 22, sealing the cylinder housing 9. The pressure force is applied through the feeding of hydraulic oil from the tank 30 into the pressure chamber behind the press piston 11, as indicated by the upward arrow show in FIG. 4. Since the filler valve 20 is closed and the clamping device 32 is deactivated, a third quantity of hydraulic oil is moved out of the compensation tank 15 with the press piston 11, which is moving from the filler valve cover 28 of the outer tube 23 in the pressure direction 29. This this quantity of hydraulic oil flows into the tank 30 (cf. FIG. 4).
[0077] In order to expose the extrusion butt 39 so that it can be sheared off before the ingot container 8, the combined cylindrical rings and clamping units 37 are switched over. The ingot container holder 7 is withdrawn via the clamped tow rods 36 by the length of the extrusion butt 39. This operating position after the stripping of the remaining extrusion butt 39 is shown in FIGS. 13a and 13b.
[0078] For the preparation of a new loading and pressing process, the ingot container holder 7 and the male die traverse 6 are moved back by the electric motors 12 and 13 as shown in FIGS. 14a, 14b, with the filler valve 20 being open to allow the hydraulic oil to flow out of the pressure chamber behind the press piston into the compensation tank 15, and with the clamping device 32 deactivated, and the cylindrical rings and clamping units 37 deactivated as well, whereupon the bar and tube extruding press 1 is ready for a new operating cycle.
