Die Casting Mold, Hot Chamber System, Method for Die Casting of Metal and Use of a Die Casting Mold

Abstract

A diecasting mold, comprising a first mold plate which is hot in operation and comprising at least one diecasting nozzle with an outlet point for a melt, and a second mold plate which forms a cold side. A mold cavity is formed between the first and second mold plates in a closed state of the diecasting mold, in which mold cavity a molded part can be produced from solidified melt introduced into the mold cavity via at least one melt channel, at least one diecasting nozzle and the at least one gate. The diecasting mold further comprises a demolding system, the demolding system comprising an ejector assembly, a drive device, and a force transmission device. A hot chamber system for diecasting metal melt according to the hot chamber method is also taught, a method for diecasting metal, and a use of a diecasting mold.

Claims

1. A diecasting mold (10), comprising a first mold plate (11) which is hot in operation and has at least one diecasting nozzle (6) with an outlet point (17) for a melt, and a second mold plate which forms a cold side, a mold cavity (14) being formed between the first and the second mold plate in a closed state of the diecasting mold (10), in which mold cavity a molded part (16) can be produced from solidified melt (8) introduced into the mold cavity (14) via at least one melt channel (4) and the at least one diecasting nozzle (6), the diecasting mold (10) further comprising a demolding system (20) for demolding the molded part (16) from the diecasting mold (10), the demolding system (20) comprising an ejector assembly (28, 30), a drive device (21), and a force transmission device (30) connected to the drive device (21) and the ejector assembly (28, 30), characterized in that the demolding system (20) is arranged outside the region of the at least one melt channel (4) and the at least one diecasting nozzle (6) and has a temperature resistance for arrangement in the first mold plate (11).

2. The diecasting mold according to claim 1, wherein the drive device (21) is peripherally arranged in the first mold plate (11), is configured as at least two linear drives and these are arranged outside the region of the at least one melt channel (4) and the at least one diecasting nozzle (6).

3. The diecasting mold according to claim 2, wherein the linear drives are configured as hydraulic drives, each comprising a hydraulic cylinder (22).

4. The diecasting mold according to claim 1, wherein at least one protective gas outlet (32) is provided for delivering a protective gas into the mold cavity (14) toward the outlet point (17).

5. The diecasting mold according to claim 4, wherein the at least one protective gas outlet (32) is arranged in the ejector assembly (28, 30).

6. The diecasting mold according to claim 5, wherein the at least one protective gas outlet (32) is arranged in the ejector wall (31) in a region that emerges from the first mold plate (11) during ejection, so that the protective gas outlet (32) is unblocked during ejection.

7. The diecasting mold according to claim 1, wherein the ejector arrangement comprises discretely acting ejector pins (28) and/or is configured as an ejector sleeve (30) in an annular shape around the outlet point (17) of the diecasting mold (6).

8. The diecasting mold according to claim 1, wherein the demolding system (20) is accessible via a mold cavity side (15) of the first mold plate (11).

9. A hot chamber system (1) for diecasting metal melt (8) according to a hot chamber method, in which melt (8) is held in liquid state at an outlet point (17) of a diecasting nozzle (6) which opens into a diecasting mold (10), the hot chamber system (1) comprising a hot chamber diecasting machine with a casting vessel and a machine nozzle (2), via which the melt (8) reaches the diecasting nozzle (6) via a melt channel (4), wherein a plug of solidified melt (8) which interrupts a melt flow can be formed at an outlet point (17) of the diecasting nozzle (6), characterized in that the diecasting mold (10) is configured according to claim 1.

10. A method for diecasting metal provided as a melt, characterized in that, in a diecasting mold (10) according to claim 1, the steps of a. closing the diecasting mold (10) by moving the first mold plate (11) and the second mold plate together and (en)closing the mold cavity (14), b. introducing the melt (8) from an outlet point (17) of the diecasting nozzle (6) into the mold cavity (14) from the first mold plate (11), which forms the gate side and has the gate point (17), c. cooling and solidifying the melt (8) to form the molded part (16), d. opening the diecasting mold (10) by lifting the second mold plate from the first mold plate (11) and releasing the molded part (16) on one side, e. activating the demolding system (20), f. ejecting the molded part (16) by releasing the adhesive connection with the mold cavity (14) in the first mold plate (11) by the force effect of the demolding system (20) are performed.

11. The method according to claim 10, wherein a protective gas flows into the mold cavity (14) during release of the molded part (16).

12. The method according to claim 11, wherein the protective gas protects an outlet point (17) of the diecasting nozzle (6) from the ingress of oxygen.

13. The method according to claim 11, wherein the protective gas flows out of the ejector assembly (28, 30).

14. The method according to claim 11, wherein nitrogen is used as the protective gas.

15. Use of a diecasting mold (10) according to claim 1, configured as a diecasting mold (10), for diecasting metal melt (8) according to the hot chamber method, in which the melt (8) is held in liquid state at an outlet point (17) of the diecasting nozzle (6).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The invention is explained in more detail below by way of a description of exemplary embodiments and their illustration in the corresponding drawings. In the drawings:

[0050] FIG. 1 schematically shows a cross-sectional view of an embodiment of a diecasting mold according to the invention;

[0051] FIG. 2: schematically shows a cross-sectional view of an embodiment of a diecasting mold according to the invention during the formation of a molded part in the casting process;

[0052] FIG. 3: schematically shows a cross-sectional view of an embodiment of a diecasting mold according to the invention during ejection of a molded part following the casting process; and

[0053] FIG. 4: shows a detail from a cross-sectional view of an embodiment of a diecasting mold according to the invention during ejection of a molded part.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0054] FIG. 1 schematically shows a cross-sectional view of an embodiment of a diecasting mold 10 according to the invention with two diecasting nozzles 6, whose outlet point 17 opens into a mold cavity 14. A molded part 16 (see FIGS. 2 and 3) can be produced in the mold cavity 14 (at the bottom side of the diecasting mold 10 or the first mold plate 11, not shown). The diecasting mold 10 is part of a hot chamber system 1, of which only a section is shown and which, in addition to the diecasting mold 10 and the machine nozzle 2 shown in part, also comprises a casting vessel not shown, from which the melt 8 passes via the machine nozzle 2 to the diecasting mold 10. Only the first mold plate 11 of the diecasting mold 10 is shown.

[0055] The second mold plate, which is not shown, adjoins in the region of the mold cavity side 15 when the diecasting mold 10 is closed. It is moved up to the first mold plate 11 prior to the casting process so that complete mold cavities 14 are formed as cavities, and is moved away to open the diecasting mold 10 for removal of the molded part 16. The second mold plate only has cavities and otherwise no internals or functional elements, which is why the second mold plate has not been shown for the sake of clarity.

[0056] Each of the mold cavities 14 is accessible by a demolding system 20, namely by ejector pins 28 on the left side or an ejector sleeve 30 on the right side of the figure, for demolding the molded part 16 from the first mold plate 11. The ejector system 20 is accessible via a mold cavity side 15 of the first mold plate 11 and comprises two drive devices 21, which in the shown embodiment are each equipped with a hydraulic cylinder 22, the piston rods 23 of which are connected to an ejector pressure plate 24. The ejector pressure plate 24 is used to transmit the drive forces from the piston rod 23 to the ejector pins 28 or to the ejector sleeve 30. The ejector pins 28 and the ejector sleeve 30 are held in an ejector holding plate 26. For axial guidance of the ejector sleeve 30, the diecasting nozzle 6 shown on the right is additionally surrounded by an unspecified guide sleeve in addition to a guide plate, while the ejector pins 28 are axially guided in the guide plate. The ejector pins 28 are also guided in the guide plate.

[0057] The hydraulic cylinders 22 are located outside the region in which the machine nozzle 2 attaches, the melt channels 4 run and the diecasting nozzle 6 is located. This deviates from the conventional central drive of the demolding system via a central ejector bolt as known from the prior art. It has been shown that the decentralized drive device 21 for generating the demolding force, which is divided among several hydraulic cylinders 22, allows the entire demolding system 20 to be arranged in the first mold plate 11, together with the advantages mentioned in the description.

[0058] Since high temperatures of several 100° occur in the first mold plate 11 in particular during diecasting due to the metal melts used in this process, the hydraulic cylinder 22 is configured to be correspondingly temperature-stable and to withstand the temperatures in the first mold plate 11, which depend on the respective melt temperature and thus have different requirements.

[0059] FIG. 2 schematically shows a cross-sectional view of an embodiment of a diecasting mold 10 according to the invention with a part of the hot chamber system 1 (see description of FIG. 1) during the formation of the molded part 16 in the casting process. The melt flow during the casting process is visualized by thick white arrows. In the process, the melt 8 flows from the machine nozzle 2, which is partially shown with its attachment to the diecasting mold 10, via the melt channels 4 into the diecasting nozzles 6.

[0060] From their outlet point 17, the melt 8 enters the mold cavity 14, which is formed between the first mold plate 11 and the second mold plate, not shown, which is in direct contact with the first mold plate 11 when the diecasting mold 10 is closed. This is where the molded part 16 is formed when the melt 8 that has entered the mold cavity 14 cools.

[0061] FIG. 3 schematically shows a cross-sectional view of an embodiment of a diecasting mold 10 according to the invention with a part of the hot chamber system 1 (see description of FIG. 1) during ejection of the molded part 16 formed from the melt 8 that has cooled after its entry into the mold cavity 14.

[0062] For ejection, the demolding system 20 is driven by the drive device 21 with the hydraulic cylinder 22, which pushes the piston rods 23 in the direction of the arrow away from the first mold plate 11 (downward in the illustration). This also causes the ejector pressure plate 24, the ejector holding plate 26, the ejector pins 28 and the ejector sleeve 30 to move out of the diecasting mold 10 on the mold cavity side 15 and into the mold cavity 14. The molded part 16 adhering in the mold cavity 14 is thereby released from the mold cavity 14 and the casting process is completed with the ejection of the molded part 16. During ejection, a protective gas connection 36 introduces protective gas, such as nitrogen, into a protective gas line 34 inside the ejector sleeve 30, but also the ejector pins 28, which are not shown as including this equipment. This protective gas exits from the protective gas outlet 32 and enters the region of the mold cavity 14 (see FIG. 4).

[0063] Subsequently, the demolding system 20 is moved back to its initial position, in particular the ejector assembly 28, 30 is retracted, so that a new molding process can begin after the diecasting mold 10 is closed, during which the second mold plate, which is not shown, is moved back into contact with the first mold plate 11.

[0064] FIG. 4 shows a detail A from a cross-sectional view of an embodiment of a diecasting mold 10 according to the invention during ejection of a molded part 16. The protective gas outlet 32 is shown to be unblocked, so that the protective gas, which flows through the protective gas line inside the ejector wall 31 to the protective gas outlet 32, can escape.

LIST OF REFERENCE NUMERALS

[0065] 1 hot chamber system (detail) [0066] 2 machine nozzle [0067] 4 melt channel [0068] 6 diecasting nozzle [0069] 8 melt [0070] 10 diecasting mold; diecasting mold [0071] 11 first mold plate [0072] 12 gate [0073] 14 mold cavity [0074] 15 mold cavity side [0075] 16 molded part [0076] 17 outlet point [0077] 20 demolding system [0078] 21 drive device [0079] 22 hydraulic cylinder [0080] 23 piston rod [0081] 24 force transmission device; ejector pressure plate [0082] 26 ejector holding plate [0083] 28 ejector assembly, ejector pin [0084] 30 ejector assembly, ejector sleeve [0085] 31 ejector wall [0086] 32 protective gas outlet [0087] 34 protective gas line [0088] 36 protective gas connection