Cooling element with spacer

Abstract

A method for producing partially hardened steel components in which a blank composed of a hardenable sheet steel is subjected to a temperature increase and shaped into a component; the component is transferred to a tool in which the heated component is cooled and thus quench hardened; during the heating of the blank or component in order to achieve the temperature increase to a temperature required for the hardening in regions that are to have a lower hardness and/or higher ductility, cooling elements are spaced apart from the surface by a small gap; the cooling element is dimensioned so that the thermal energy acting on the region that remains ductile flows through the component into the cooling element, characterized in that in order to space the cooling element apart from the component, micro-nubs or knobs are used, which are distributed over the area of the cooling element.

Claims

1. A method for producing partially hardened steel components, comprising: partially spacing at least one cooling element apart from a surface of a blank by a small gap, wherein the blank is composed of a hardenable sheet steel, and the at least one cooling element is positioned near regions of the blank that are to have a lower hardness and/or higher ductility; using locally delimited point-shaped or linear spacerscomprising micro-nubs or knobsdistributed over an area of the at least one cooling element in order to space the at least one cooling element apart from the blank, wherein the spacers are positioned on top surfaces of at least some of a plurality of cooling fins; heating the blank by transporting the blank and the at least one cooling element through a furnace in order to achieve a temperature of the blank required for partial hardening, wherein the at least one cooling element is dimensioned with regard to its expanse and thickness, its thermal conductivity, and its heat capacity and/or with regard to its emissivity so that thermal energy acting on a region that remains ductile is transmitted through the blank into the at least one cooling element; after reaching a desired temperature of the blank, transferring the heated blank to a forming tool; and shaping the heated blank into a component while simultaneously partially quench-hardening the heated blank.

2. The method according to claim 1, comprising using a cooling element composed of a heat-resistant metal; wherein the cooling element is embodied with at least one surface whose outline is embodied so that it is spaced apart from the blank by the micro-nubs or knobs with a small gap, in particular a gap 0.1 mm to 2.5 mm wide.

3. A device for producing partially hardened steel components comprising: a cooling element for the production of partially hardened steel components, the cooling element comprising a plurality of cooling fins, and micro-nubs or knobs, which are distributed over top surfaces of at least some of the fins in order to space the blank to be heated apart from the cooling element, wherein the micro-nubs or micro-knobs protrude from a respective surface of the cooling element by 0.1 to 2.5 mm; a furnace through which the cooling element is transported during the heating of the blank; a device for transporting the cooling element and a blank thereon through the furnace; a forming tool; and a device for transferring the heated blank to the forming tool; partially spacing at least one cooling element apart from a surface of a blank by a small gap, wherein the blank is composed of a hardenable sheet steel, and the at least one cooling element is positioned near regions of the blank that are to have a lower hardness and/or higher ductility; using locally delimited point-shaped or linear spacerscomprising the micro-nubs or knobsdistributed over an area of the at least one cooling element in order to space the at least one cooling element apart from the blank, wherein the spacers are positioned on top surfaces of at least some of a plurality of cooling fins; heating the blank by transporting the blank and the at least one cooling element through the furnace in order to achieve a temperature of the blank required for partial hardening, wherein the at least one cooling element is dimensioned with regard to its expanse and thickness, its thermal conductivity, and its heat capacity and/or with regard to its emissivity so that thermal energy acting on a region that remains ductile is transmitted through the blank into the at least one cooling element; after reaching a desired temperature of the blank, transferring the heated blank to the forming tool; and shaping the heated blank into a component while simultaneously partially quench-hardening the heated blank.

4. The device according to claim 3, wherein the micro-nubs or knobs are embodied of one piece with the cooling element or are inserted with a shaft into corresponding bores of the cooling element; and the inserted micro-nubs or knobs are composed of a metal, a metal alloy, or a ceramic.

5. The device according to claim 3, wherein contact surfaces, which are embodied at a free end of the micro-nubs or knobs and are for a blank to be heated, are embodied so that less than 1.5% of the area of the blank is contacted by the micro-nubs or knobs.

6. The device according to claim 3, further comprising air outlet elements that are distributed over the area of the cooling element and the air outlet elements are connected to at least one air supply line or a supply line for another gas.

7. The device according to claim 6, wherein an arrangement of air outlet elements and their number depend on a weight of the blank; and wherein the number and distribution of the air outlet elements and the air pressure are matched to each other so as to ensure a reliable lifting of the blank away from the cooling element.

8. The device according to claim 3, wherein the cooling fins are positioned in a box in such a way that an outer wall is formed, which prevents gas from flowing outward or downward; and further comprising an air cushion produced in such a way that pressurized gas is supplied between the fins to an underside of the blank or component.

9. A method for producing partially hardened steel components, comprising: cold forming a blank composed of a hardenable sheet steel into a component; partially spacing at least one cooling element apart from a surface of the component by a small gap, wherein the at least one cooling element is positioned near regions of the component that are to have a lower hardness and/or higher ductility; using locally delimited point-shaped or linear spacerscomprising micro-nubs or knobsdistributed over an area of the at least one cooling element in order to space the at least one cooling element apart from the component, wherein the spacers are positioned on top surfaces of at least some of a plurality of cooling fins; heating the component by transporting the component and the at least one cooling element through a furnace in order to achieve a temperature of the component required for partial hardening, wherein the at least one cooling element is dimensioned with regard to its expanse and thickness, its thermal conductivity, and its heat capacity and/or with regard to its emissivity so that thermal energy acting on a region that remains ductile is transmitted through the component into the at least one cooling element; after reaching a desired temperature of the component, transferring the heated component to a tool in which the heated component is simultaneously cooled and thus partially quench-hardened.

10. The method according to claim 1, comprising partially not, or only briefly, bringing the blank to a temperature greater than an austenitizing start temperature during the heating process.

11. The method according to claim 9, comprising using a cooling element composed of a heat-resistant metal; wherein the cooling element is embodied with at least one surface whose outline is embodied so that it is spaced apart from the component by the micro-nubs or knobs with a small gap, in particular a gap 0.1 mm to 2.5 mm wide.

12. A device for producing partially hardened steel component, comprising: a forming tool; a cooling element for the production of partially hardened steel components, the cooling element comprising a plurality of cooling fins, and micro-nubs or knobs, which are distributed over top surfaces of at least some of the fins in order to space the component to be heated apart from the cooling element, wherein the micro-nubs or micro-knobs protrude from a respective surface of the cooling element by 0.1 to 2.5 mm; a furnace through which the cooling element is transported during the heating of the component; a device for transporting the cooling element and a blank thereon through the furnace; a tool for simultaneously cooling and partially quench-hardening the blank; and a device for transferring the heated blank to the cooling and quench-hardening tool; cold forming a blank composed of a hardenable sheet steel into a component; partially spacing at least one cooling element apart from a surface of the component by a small gap, wherein the at least one cooling element is positioned near regions of the component that are to have a lower hardness and/or higher ductility; using locally delimited point-shaped or linear spacerscomprising the micro-nubs or knobsdistributed over an area of the at least one cooling element in order to space the at least one cooling element apart from the component, wherein the spacers are positioned on top surfaces of at least some of a plurality of cooling fins; heating the component by transporting the component and the at least one cooling element through the furnace in order to achieve a temperature of the component required for partial hardening, wherein the at least one cooling element is dimensioned with regard to its expanse and thickness, its thermal conductivity, and its heat capacity and/or with regard to its emissivity so that thermal energy acting on a region that remains ductile is transmitted through the component into the at least one cooling element; after reaching a desired temperature of the component, transferring the heated component to a tool in which the heated component is simultaneously cooled and thus partially quench-hardened.

13. The device according to claim 12, wherein the micro-nubs or knobs are embodied of one piece with the cooling element or are inserted with a shaft into corresponding bores of the cooling element; and the inserted micro-nubs or knobs are composed of a metal, a metal alloy, or a ceramic.

14. The device according to claim 12, wherein contact surfaces, which are embodied at a free end of the micro-nubs or knobs and are for a component to be heated, are embodied so that less than 1.5% of the area of the component is contacted by the micro-nubs or knobs.

15. The device according to claim 12, further comprising air outlet elements that are distributed over the area of the cooling element and the air outlet elements are connected to at least one air supply line or a supply line for another gas.

16. The device according to claim 15, wherein an arrangement of air outlet elements and their number depend on the weight of the component; and wherein the number and distribution of the air outlet elements and the air pressure are matched to each other so as to ensure a reliable lifting of the component away from the cooling element.

17. The device according to claim 12, wherein the cooling fins are positioned in a box in such a way that an outer wall is formed, which prevents gas from flowing outward or downward; and further comprising an air cushion produced in such a way that pressurized gas is supplied between the fins to an underside of the blank or component.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be explained in detail by way of example in conjunction with the drawings:

(2) FIG. 1 is a schematic top view of a cooling element according to the invention.

(3) FIG. 2 shows the cooling element from FIG. 1, viewed from a different angle.

(4) FIG. 3 is a very schematic sectional view of a cooling element according to the invention.

(5) FIG. 4 is a schematic sectional view of another embodiment of the cooling element, with air outlets for producing an air cushion.

(6) FIG. 5 shows a perspective view of a cooling element with a fin structure and a component resting against it.

(7) FIG. 6 shows the cooling element according to FIG. 5, without the component resting against it.

(8) FIG. 7 shows a side view of the cooling element according to FIG. 5, with a part of a component resting against it.

(9) FIG. 8 shows the cooling element according to FIG. 6 from another perspective.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(10) A cooling element 1 according to the invention has an in particular metallic body 2, particularly composed of a thermally conductive metallic alloy. The cooling element 1 has a working surface 3 which is oriented toward a component to be heated. The working surface has an outline that essentially corresponds to that of the component to be heated; this outline contains surfaces 4, grooves 5, and positive radii 6 as well as negative radii 7. In particular on the surfaces 4, the spacers according to the invention are embodied in the form of micro-nubs 8 or knobs 8. Starting from a surface 4, the knobs 8 have a first width and taper toward a component to be placed against them, reaching a contact surface 9 against which the component rests. The micro-nubs or knobs 8 in this case can be embodied as anything from flat to dome-shaped to sharply conical.

(11) Regardless of the shapefor example, linear protrusions are also Conceivableit is important that there be as small as possible a contact surface of the spacers, e.g. micro-nubs or knobs, relative to the component; the height of the knobs starting from the flat surface of the cooling element is 0.2 to 2 mm.

(12) The micro-nubs or knobs can be composed of the same material as the cooling element and in particular, can be embodied of one piece with the cooling element e.g. produced through material-removing machining. The micro-nubs or knobs can also be very easily attached to the cooling element by means of build-up welding. In addition, the vicinity of the micro-nubs or knobs, bores can be provided in the cooling element; starting from their base, the micro-nubs have an axially extending shaft, which corresponds to the bore (not shown) and with which the micro-nubs 8 or knobs 8 are inserted into the cooling element 1.

(13) Such micro-nubs or knobs (8) with a shaft (not shown) can also be composed of a different material, in particular ceramic, other metal alloys, or other metals.

(14) In an embodiment of the cooling element 1 with fins 10, the corresponding work surface 3 is primarily composed of the tops 11; in this case, the knobs 8 or micro-nubs 8 are likewise distributed in a suitable fashion, for example are only situated on only some of the tops 11 of the fins 10. The fins 10 are secured to one another with suitable elements such as clamps 12 or the like.

(15) The cooling element can also be embodied as hollow or box-like (FIG. 3); the cooling element 1 has a box base body 14 and a working surface element 15 placed onto the latter.

(16) In another advantageous embodiment, the spacing of the work piece 16 is embodied in that the work piece 16 is spaced apart from the work surface 3 with a small gap 17 by means of an air cushion. To this end, the work surface 3 is provided with bores 18 which with a box-like embodiment of the cooling element 1 extend into the hollow interior of the box 19. The hollow box interior 19 in this case is preferably acted on with pressurized gas, which flows out of the bores 18 into the gap 17 with a flow speed and pressure such that a component 16 does not touch the work surface 3. In particular, the temperature of the gas in this case can be adjusted and especially, can be introduced into the cavity 19 at a predetermined temperature. After the component 16 is removed from the working surface 3 and the cooling element is returned to a furnace entrance, the cavity 19 can be flushed with a very cold gas, which flows out through the openings 18 and thus in particular produces a cooling of the entire cooling element.

(17) This flushing and the resulting cooling can advantageously also take place during the passage through the furnace.

(18) The cavity 19 in this case can be embodied as though composed of plate-like elements (FIG. 4) 15, 14, but the cooling element can also be embodied as largely solid, with a bore (not shown) that extends through the cooling element 1 and can lead from the distributor bores to the bores 18. A cooling element of this kind is significantly more solid and therefore has a higher heat capacity.