HOT-FORMING LINE FOR MANUFACTURING HOT-FORMED AND PRESS-HARDENED STEEL-SHEET PRODUCTS, AND METHOD FOR OPERATING SAID HOT-FORMING LINE

Abstract

A hot-forming line and a method for operating the hot-forming line is disclosed having a temperature-control station and a hot-forming and press-hardening tool. A linear conveyor system for conveying the metal blank or the formed steel-sheet products, respectively, through the hot-forming line is provided.

Claims

1. Hot-forming line for manufacturing hot-formed and press-hardened steel-sheet products, having a temperature-control station for heating at least one metal blank, and a hot-forming and press-hardening tool, wherein a linear conveyor system which is configured from at least two mutually opposite parallel rails is provided along the hot-forming line, wherein the rails are displaceable in at least one translatory direction, and gripper elements are disposed on the rails, wherein the gripper elements are displaceable in the axial direction of the rails, and in that the gripper elements are capable of being lifted and lowered in a manner orthogonal to the axial direction of the rails.

2. Hot-forming line according to claim 1, wherein active grippers are provided for acquiring a metal blank, wherein the active grippers carry out a clamping movement, the active grippers in particular being configured as blank grippers and temperature-control grippers.

3. Hot-forming line according to claim 1, wherein passive grippers which by way of the steel-sheet product bearing thereon by virtue of the influence of gravity carry out a lifting function are provided for acquiring a finished steel-sheet product, the passive grippers being configured in particular as product grippers.

4. Hot-forming line according to claim 1, wherein the rails are displaceable in a manner orthogonal to the axial direction thereof, and outwardly and inwardly, respectively, in relation to the hot-forming line, in particular by way of a synchronous drive.

5. Hot-forming line according to claim 1, wherein all gripper elements carry out the movement in the axial direction of the rails by way of a synchronous drive, or by way of a displacement of the rails.

6. Hot-forming line according to claim 1, wherein a translatory displacement path of the gripper elements from a resting position to a gripping position is provided to be between 5 and 250 mm, in particular 10 to 50 mm.

7. Hot-forming line according to claim 1, wherein the temperature-control station is flange-fitted to the hot-forming and press-hardening tool, or in that the temperature-control station and the hot-forming and press-hardening tool are disposed so as to be directly next to one another at a spacing of less than 50 cm, particularly less than 20 cm, preferably equal to or less than 10 cm.

8. Hot-forming line according to claim 1, wherein the temperature-control station is actuated so as to be synchronous with the cycle of the drive of the hot-forming and press-hardening tool, or in that the temperature-control station, for the opening movement thereof, is actuated so as to be temporally delayed in relation to the hot-forming and press-hardening tool.

9. Hot-forming line according to claim 1, wherein the temperature-control station and the hot-forming and press-hardening tool are opened and closed, respectively, in a synchronous manner by way of the same drive.

10. Hot-forming line according to claim 1, wherein the hot-forming line is configured so as to have dual parallel action such that two metal blanks are simultaneously heatable, and two steel-sheet products are simultaneously hot-formable and press-hardenable.

11. Method for operating a hot-forming line having the features of claim 1, wherein a metal blank is acquired and by way of an axial movement of at least two mutually opposite blank grippers is conveyed into the temperature-control station and is deposited therein, wherein in parallel therewith a heated metal blank in the temperature-control station is acquired by at least two mutually opposite temperature-control grippers and is conveyed into the hot-forming and press-hardening tool, wherein in parallel therewith two formed and hardened steel-sheet products from the hot-forming and press-hardening tool are acquired by at least two mutually opposite product grippers and are conveyed to a depository stack, or in that a downstream transfer of the completely manufactured steel-sheet products onto a depository stack is performed.

12. Method for operating a hot-forming line, according to claim 11, wherein an opening movement of the temperature-control station is carried out so as to be temporally delayed with respect to the opening movement of the hot-forming and press-hardening tool.

13. Method for operating a hot-forming line, according to claim 11, wherein in the case of a dual parallel-action hot forming line two gripper-element pairs which carry out the transportation movement of two metal blanks and/or steel-sheet products are variable in the mutual spacing thereof in the axial direction.

14. Method for operating a hot-forming line, according to claim 11, wherein a time for transporting a metal blank, or the steel-sheet product, respectively, is less than 5 s, in particular less than 3 s.

Description

[0030] Further advantages, features, properties, and aspects of the present invention are the subject matter of the following description explained. Preferred variants of design embodiment are illustrated in the schematic figures. The latter assist in readily understanding the invention. In the figures:

[0031] FIGS. 1 to 3 show the course of the method of a hot-forming line according to the invention;

[0032] FIGS. 4a and 4b show a hot-forming and press-hardening tool having a temperature-control station that is laterally flange-fitted to the former;

[0033] FIG. 5 shows a hot-forming and press-hardening tool having temperature-control stations that are laterally flanged to the former;

[0034] FIG. 6 shows a hot-forming and press-hardening tool as per FIG. 5, in an alternative variant of design embodiment;

[0035] FIGS. 7a and 7b show a lifting function of a linear conveyor system having fixed gripper elements;

[0036] FIGS. 8a and 8b shows a lifting function of a linear conveyor system having gripper elements which are movable relative to one another;

[0037] FIGS. 9a to 9c show active grippers according to the invention;

[0038] FIG. 10 shows a hot-forming line having a divisible rail;

[0039] FIG. 11 shows a hot-forming line having a temperature-control station and a hot-forming and press-hardening tool, mutually spaced apart by less than 50 cm.

[0040] In the figures, the same reference signs are used for identical or equivalent components, even if and when a repeat description is dispensed with for reasons of simplification.

[0041] FIG. 1 shows a hot-forming line 1 according to the invention, having a temperature-control station 2, and a hot-forming and press-hardening tool 3, and linear conveyor system 4 disposed thereon. The linear conveyor system 4 has two rails 5, disposed so as to be mutually parallel, wherein gripper elements are disposed on the rails 5. Two blanks grippers 6 are disposed from left to right in relation to the image plane. Two temperature-control grippers 7 are disposed in the center in relation to the image plane, and two product grippers 8 are disposed on the right side in relation to the image plane. The hot-forming line 1 thus has a dual parallel action. Said hot-forming line 1 may also be configured so as to have a single action, a tripe parallel action, a quadruple parallel action, or a multiple parallel action. An overall displacement path 6 is furthermore illustrated.

[0042] According to the variant presently illustrated, the gripper elements are locationally fixed to the rails 5 in relation to the axial direction 9 of the rails 5, wherein the rails 5 are movable in the axial direction 9 thereof. Alternatively, it would also be conceivable for the gripper elements to be displaceable in the axial direction 9 in relation to the rails 5.

[0043] It is furthermore illustrated that the rails 5 have carried out a relative movement 10 in an inward orthogonal manner in relation to the axial direction 9 of the former. The respective gripper elements have thus been brought to engage with the metal blanks 11, the metal blanks 12 to be heated, and the steel-sheet products 13, respectively.

[0044] The linear conveyor system 4 then carries out a transportation movement 14 in the axial direction 9 of the rails 5. The terminal position is illustrated in FIG. 2. The formed steel-sheet products 13 are deposited onto a schematically illustrated depository stack 15. The heated metal blanks 13 are deposited onto the hot-forming and press-hardening tool 3. The freshly received metal blanks 11 are deposited onto the temperature-control station 2, and fresh metal blanks 11 are in turn offered up. Subsequently, an outward movement 16 is carried out by the rails 5 such that the entire rails 5 having the respective gripper elements are moved outward in relation to the axial direction 9 of the rails 5, so as to no longer be engaged with the metal blanks 11, 12, and the steel-sheet products 13.

[0045] Thereupon, a return movement 17 is carried out in the axial direction 9 of the rails 5, this return movement 17 in particular being carried out by both rails 5 in a synchronous manner, as is shown in FIG. 3. Thereafter, the procedure recommences, as is illustrated in FIG. 1. The returned rails 5 are converged such that the gripper elements are brought to engage with the heated metal blanks 12 and the steel-sheet products 13.

[0046] FIGS. 4a and 4b each show the hot-forming line 1 according to the invention in a side view. The rails 5 can be seen. Metal blanks 11 that have been received by a metal-blank stack 18 are infed to the temperature-control station 2. The temperature-control station 2 herein is optionally flange-fitted to the press frame 19. According to FIG. 4b, the hot-forming and press-hardening tool 3 and the temperature-control station 2 have carried out a closing movement in a synchronous manner, heating the metal blanks 11 that are placed into the temperature-control station 2, and forming the heated metal blanks 12 to the steel-sheet products 13 which are stored on a depository stack 15. The temperature-control station 2 herein has an actuator 20 such that the temperature-control station 2 may be actuated independently of the hot-forming and press-hardening tool 3. The actuator 20 may be disposed on top of or below the temperature-control station 2.

[0047] FIG. 5 shows an alternative variant of design embodiment of the hot-forming line 1, having a hot-forming and press-hardening tool and a separate downstream temperature-control station 21, the temperature-control station 21 and the hot-forming and press-hardening tool 24 being connected to a common control unit 22. One control unit 22 herein actuates all individual stations in a synchronous-cycle manner, or even a simultaneous manner. Vibration dampers 23 may preferably be employed in the coupling in the case of all constructive units that are illustrated in the figures. The temperature-control station 21 serves for the localized softening or another localized setting of the microstructure of the press-hardened steel-sheet product.

[0048] FIG. 6 shows a variant of design embodiment according to FIG. 5, the point of difference being that the temperature-control station 2 and the temperature-control station 21 are coupled to an upper tool 25 of the hot-forming and press-hardening tool 24, or to the press frame 19 thereof, respectively, such that the opening and closing movements of the upper tool 25 are carried out so as to be synchronized in terms of the cycle rate and to be simultaneous with those of the temperature-control station 2.

[0049] FIGS. 7a and 7b show a lifting procedure of the rails 5 having the blank grippers 6. The rails 5 have carried out a converging movement 10 in a manner orthogonal to the axial direction 9 of said rails 5, such that the blank grippers 6 are located below the metal blank 11 in relation to the vertical direction V. Subsequently thereto, a lifting movement is carried out by the rails 5, as is illustrated in FIG. 7b. This means that the entire rails 5 are moved upward in the vertical direction V. The metal blank 11, as it were, bears on the blank grippers 6 and is likewise lifted.

[0050] FIGS. 8a and 8b show a variant of design embodiment that is an alternative to the above. Herein, not the rails 5 but only the blank grippers 6 are lifted in relation to the vertical direction V. Said blank grippers 6 are thus mounted on the rails 5 so as to be movable relative to the vertical direction V, and may also be lifted or lowered, respectively.

[0051] FIGS. 9a to 9c show a relative movement 10 that is analogous to that of FIGS. 8a and 8b, the point of difference being that the blank grippers 6 are presently illustrated as active grippers. The latter are shown in an open position according to FIG. 9a, such that the rails 5 have carried out a converging movement 10. According to FIG. 9b, the blank grippers 6 as active grippes are then closed, and according to FIG. 9c are again lifted in relation to the vertical direction V.

[0052] FIG. 10 shows the hot-forming line 1 according to the invention in a resting state. The upper rail 5 in relation to the image plane, in the axial direction 9 of the former, is divided into two and outwardly displaced. On account thereof, free access 26 to the hot-forming and press-hardening tool 3 that is located therebehind is enabled such that a schematically indicated tool changeover 27 may take place. Subsequently thereto, the two rail parts are again converged, coupled to one another, and the hot-forming line 1 is operated.

[0053] It is furthermore illustrated that two gripper pairs which in relation to the image plane are disposed in the center and which in particular are temperature-control grippers 7, are variable in terms of the mutual spacing A1 thereof. On account thereof, it is possible for two temperature-controlled blanks to be received at a spacing B1 from the temperature-control station 21, and to be deposited in the hot-forming and press-hardening tool 24 at a spacing B2 by enlarging the mutual spacing A1 of the temperature-control grippers 7 in the axial direction 9 of the rails 5. Wherein, the spacing B2 is longer than the spacing B1.

[0054] FIG. 11 shows a hot-forming line 1. The temperature-control station 2 and the hot-forming and press-hardening tool 3 are disposed so as to be tightly close to one another at a spacing 28 of less than 50 cm. The temperature-control station 2 and the hot-forming and press-hardening tool 3 may be driven in a synchronous manner.

[0055] The may be performed by way of a common controller or by means of a superordinate controller of two connected individual controllers. A common opening phase is important, such that the linear conveyor system 4 may perform respective transportation in a short time.