EP3003604B1 - Method and device for casting a cast part - Google Patents

Description

The invention relates to a method for casting a casting according to the preamble of claim 1

Furthermore, the invention relates to a device for tilt casting according to the preamble of claim 9.

A method for Kippgießen is ausß the WO2010 / 058003A1 known. In the known method, the molten metal is poured into a casting mold by means of a casting container, also referred to as a ladle. In the known method, the process of Umgießens by tilting the casting container is set in motion. In this case, the casting container or the level of the melt in the casting container is higher than the casting mold, so that the melt enters the casting container with relatively high kinetic energy.

Other methods and devices for Kippgießen are also in the US 5704413A and the DE 102010022343 A1 described. A method and a device of the type mentioned are from the DE 102009023881 A1 known.

A disadvantage of the known methods is that swirling in the melt and thus impairment of the microstructure of the casting may occur at the beginning of the casting of the molten metal from the casting container into the casting mold.

It is therefore an object of the invention to provide a new Kippgießverfahren, which does not have the disadvantages mentioned above.

This object is achieved by a method of the type mentioned according to the invention by the features of the characterizing part of claim 1.

The invention makes it possible that pouring the melt into the mold can be very quiet and turbulence-free. Since the calmed down level of the molten metal is already at the level of the casting mold at the beginning of the casting, the molten metal enters at low speed into the mold, so that the mold is filled with a calmed melt front. As a result, turbulence and irregularities in the casting can be avoided very well.

According to a preferred embodiment, which allows a particularly smooth pouring of the molten metal into the mold cavity, it can be provided that the at least one casting container and the casting mold are positioned prior to casting so that the calmed metal melt level in the at least one casting container at least the same height with the lowest lying portion of the mold cavity.

A rapid settling of the molten metal before Umgießen and achieving a smooth melt front at the beginning of the Umgießens be favored that the at least one casting container and the mold are positioned prior to the Umgießen so that the calmed down level of the molten metal at the beginning of the Umgießens Wall section, in particular a bottom, the at least one casting container extends.

To be particularly advantageous, it has been found that the casting container has a directly opening into the mold cavity gate and the mold cavity is connected directly to the casting container during the Umgießens the molten metal via the gate.

According to an advantageous development of the invention, it may be provided that the gate extends substantially over a whole of the casting container facing width of the mold cavity, wherein in the gate part of the melt stops as a feeder volume.

A simple starting of the casting process can be achieved by initiating the casting process of the molten metal by tilting the casting container in the direction of the casting mold, or by turning the casting container and the casting mold jointly and in the same direction about a common axis to initiate the casting process.

A further advantageous variant of the invention consists in that the casting container filled with the molten metal is guided in a pendulum motion to the casting mold, wherein the oscillating movements take place in opposite directions to fluctuations of the molten metal. This variant of the invention enables a very fast processing time, since the Umgießen does not have to wait until the molten metal has calmed down after the introduction of the casting container to the mold.

According to a preferred embodiment of the invention, the level of the molten metal is detected by means of sensors.

The above object can also be achieved with a device of the type mentioned according to the invention by the features of the characterizing part of claim 9.

The device according to the invention allows a very smooth pouring of the melt from the casting container into the casting mold. It is an advantage of the solution according to the invention that a melting of the melt when poured into the casting mold can be very well prevented and approximately laminar flow conditions are ensured.

An advantageous variant of the invention, which also ensures an optimum sealing surface between casting container and mold, provides that the end faces of casting container and feeder with respect to their surfaces and their contours correspond to each other.

The pouring behavior of the melt into the casting mold can be further improved in that an inner surface of the at least one casting container and the outer surface of the at least one casting container extend parallel to one another.

Very good flow conditions and a very smooth melt front during the pouring of the melt from the casting into the mold can be achieved, that the at least one casting container has a pouring over which the melt is poured into the at least one mold, wherein the width of the pouring edge a width of the equivalent.

The Umgießen can be further improved in that the pouring edge of the at least one casting container and a pouring edge of the at least one feeder are arranged congruently with each other or form a step whose height is less than 10 mm.

In order to allow a very smooth flow of the melt in the feeder, it may be provided that a surface of the feeder is formed flat in an adjoining its Eingießkante range and with the end face of the feeder an angle between 80 and 100 °, preferably an angle between 85 ° and 95 °.

In order to ensure a smooth inflow of the melt from the feeder into a mold cavity of the casting mold, it may be provided that the feeder has a section at an angle of more than 90 °, preferably an angle, at a rear portion of the surface viewed in the pouring direction greater than 100 ° and less than 160 °, with the area adjacent to the pouring edge of the surface of the feeder includes. To be particularly favorable, it has been found when the feeder is formed by at least one sand mold.

Advantageously, the controller is arranged to control the movement of the robot arm and an actuator for actuating the mold so that the level of the molten metal at the beginning of pouring the molten metal from the casting container into the mold is calmed and level with an inside the mold is located.

Fig. 1

zeigt die Position eines Gießbehälters und einer Gießform vor einem Umgießen der Metallschmelze von dem Gießbehälter in die Gießform;

Fig. 2

zeigt den Gießbehälter und die Gießform aus Fig. 1 in einer ersten Position während des Umgießens;

Fig. 3

zeigt den Gießbehälter und die Gießform aus Fig. 1 in einer zweiten Position während des Umgießens der Metallschmelze;

Fig. 4

zeigt den Gießbehälter und die Gießform aus Fig.1 in einer Position, in welcher die Metallschmelze vollständig von dem Gießbehälter in die Gießform umgegossen ist;

Fig. 5

zeigt einen Sensor zur Erfassung eines Niveaus der Metallschmelze;

Fig. 6

zeigt eine Vorderansicht des Gießbehälters aus den Figuren 1 bis 4;

Fig. 7

zeigt eine Variante eines Gießbehälters;

Fig. 8

zeigt einen Teil einer erfindungsgemäßen Vorrichtung in einer perspektivischen Ansicht und

Fig. 9

zeigt einen Schnitt durch die in Fig. 8 dargestellte Vorrichtung.

The invention together with further advantages will be explained in more detail below with reference to a non-limiting embodiment, which is shown in the drawings. Each shows in a highly schematically simplified representation:

Fig. 1

shows the position of a casting container and a mold before pouring the molten metal from the casting container into the casting mold;

Fig. 2

shows the casting container and the mold Fig. 1 in a first position during transfusion;

Fig. 3

shows the casting container and the mold Fig. 1 in a second position during the pouring of the molten metal;

Fig. 4

shows the casting container and the mold Fig.1 in a position in which the molten metal is completely transferred from the casting container into the casting mold;

Fig. 5

shows a sensor for detecting a level of the molten metal;

Fig. 6

shows a front view of the casting container from the FIGS. 1 to 4 ;

Fig. 7

shows a variant of a pouring container;

Fig. 8

shows a part of a device according to the invention in a perspective view and

Fig. 9

shows a section through the in Fig. 8 illustrated device.

By way of introduction, it should be noted that in the differently described embodiments, the same parts are provided with the same reference numerals or the same component names, wherein the disclosures contained in the entire description can be mutatis mutandis to the same parts with the same reference numerals or component names. Also, the location information chosen in the description, such as top, bottom, side, etc. related to the immediately described and illustrated figure and are to be transferred to the new situation mutatis mutandis when a change in position. Furthermore, individual features or combinations of features from the different exemplary embodiments shown and described can also represent independent, inventive or inventive solutions.

All information on ranges of values in representational description should be understood to include any and all sub-ranges thereof, eg the indication 1 to 10 to be understood that all partial areas, starting from the lower limit 1 and the upper limit 10 are included, ie all partial areas begin with a lower Limit of 1 or greater and end at an upper limit of 10 or less, eg 1 to 1.7, or 3.2 to 8.1 or 5.5 to 10.

According to Fig. 1 - 4th the casting takes place in a method according to the invention for casting a casting according to the Kippgießprinzip. The method according to the invention is referred to as balanced level casting. In this case, a molten metal 1 is recast from a tiltable casting container 2 into a casting mold 3 with a mold cavity 4 depicting the casting. In the Figures 1 - 4 the casting container 2 and the casting mold 3 are shown in different temporally successive positions. The Umgießen can also be done by means of two or more parallel to each other arranged casting container 2, for example, ladles.

The chronological order of the process begins with Fig. 1 and ends with Fig. 4 , Here, the Eingießvorgang the molten metal 1 can be initiated by tilting the casting container 2 in the direction of the mold 3. As a result, the casting container and the casting mold can be tilted together and in the same direction during the pouring of the molten metal.

As Fig. 1 can be seen, the casting container 2 and the mold 3 are arranged in front of each other before pouring the molten metal 1. The casting container 2 can be spatially separated from the casting mold 3 during filling with the molten metal 1. After filling the casting container 2 with a quantity of molten metal required for filling the casting mold 3, the casting container 2 can be guided, for example, by a robot arm to the casting mold 3 and fixed by the robotic arm against the casting mold 3. In Fig. 3 the robot arm is indicated by dashed lines and provided with the reference numeral 13. Advantageously, the casting container 2 can also be mechanically and tightly connected to the casting mold 3, for example by hanging the casting container 2 into the casting mold 3. The casting mold 3 and the casting container 2 can then be tilted together about an axis. The robot arm 13 can release the casting container 2 after connecting the casting container 2 with the casting mold 3 and is available for another working process.

In a second step, the molten metal 1 in the casting container 2 is calmed. This is done by waiting until the position of the molten metal 1 in the casting container 2 has stabilized and has reached a constant level. The casting container 2 and the casting mold 3 are in this case positioned so that a calmed level a of the molten metal 1 before pouring the molten metal from the casting container 2 into the casting mold 3 in the casting container 2 is at the same height as a portion of an inner side of the casting mold 3, like this in Fig. 1 is shown. The soothing of the molten metal 1 in the casting container 2 serves to ensure the quietest possible sprue. The level of the melt can be detected by means of one or more sensors. To reduce oxide formations, it may further be provided that the casting container 2 is filled with a protective gas. For this purpose, an embodiment is particularly suitable as in Fig. 6 is shown, in which the casting container 2 can be closed with a cover 19 after filling with the molten metal 1.

The casting container 2 may have in its deepest region at least one flat, rectilinearly extending bottom section 5, wherein the casting container 2 are positioned prior to casting so that the calmed down level a of the molten metal runs parallel to the bottom section 5 at the beginning of the casting. At this point it should be noted that the casting container 2 can also have a different bottom shape, for example rounded.

How out Fig. 1 It can also be seen that the casting container 2 and the casting mold 3 can be positioned prior to pouring over the molten metal 1 such that a normal n1 is applied to the bottom section 5 or to an opening 6 of the casting container 2 opposite the bottom section and a normal n2 to a pouring opening 7 the mold 3 form an angle α of about 45 ° - 100 ° with each other. This angle α can remain constant during the Umgießens, so that the relative position of the casting container 2 and mold 3 does not change during the Umgießens. Alternatively, however, the angle α during the Umgießens vary and thus change the relative position of the casting container 2 and mold 3 to each other.

The inventive method makes it possible to keep the calmed level a of the molten metal 1, which is necessarily horizontal, parallel to a bottom of the casting container 2 at the time of commencement of pouring, said level a preferably the lowest level of the mold cavity 4 of Mold 3 corresponds to the beginning of the Umgießens. At the beginning of the Umgießens the casting mold 3 is opposite to in Fig. 4 shown Position pivoted by approx. -90 ° at the end of the encapsulation, as from a comparison of Fig.1 and 4 is apparent. In the balanced level casting method according to the invention, the movements of the casting container and / or of the casting mold during casting can be controlled such that the surface of the melt is approximately calmed during the entire casting process.

Furthermore, the casting container 2 filled with the molten metal 1 can, for example, be guided in a pendulum motion to the casting mold, wherein the pendulum movement can take place in opposite directions to fluctuations in the molten metal 1.

The casting container 2 may have a directly opening into the mold cavity 4 gate, wherein the mold cavity 4 is connected during the Umgießens the molten metal 1 via a gate directly to the casting container 2. In the case just mentioned, the gate of the casting container 2 may be formed by a portion 12 of the casting container 2, which has a in Fig. 6 has shown pouring opening 18.

As an alternative to a realization of a gate on the casting container 2, the casting mold 3 may have a gate 8. This gate 8 may have a plurality of channels 9, 10, 11, which may serve for filling the mold cavity 4 and for venting during filling. Furthermore, the casting container 2 on a side facing the casting mold 3 may have the portion 12 corresponding to the cut 8 in order to ensure a good connection between the casting container 2 and the casting mold 3. The portion 12 and a cooperating with this portion of the gate 8 are preferably formed congruent to each other, wherein the portion 12 engages in the gate 8 and may be surrounded by this, so that a mechanical connection between the casting container 2 and mold 3 may be formed.

The gate 8 may extend substantially over an entire width of the mold cavity 4 facing the casting container 2. In section 8, a part of the molten metal can remain as feeder volume.

In the Fig. 3 illustrated device 14 for carrying out the method according to the invention, one or more sensors 15 for detecting the level of the molten metal 1 in the pouring container 2 and a controller 16 connected to the sensor 15, for example a suitably programmed signal or microprocessor, which is adapted to control the robot arm 13 in response to signals generated by the sensor 15. As in Fig. 5 As shown, the sensor 15, for example, a photosensitive sensor, receives light reflected from the surface of the molten metal of a light source 20 and converts it into electrical signals. The intensity of the light measured by the sensor 15 changes with variations in the level of the metal lard against a calmed surface, so that it can be easily recognized with the illustrated construction, whether the level of the molten metal 1 is calmed.

The controller 16 may be configured to control the movement of the robot arm 13 and an actuator 17 for operating the mold 3 so that the level of the molten metal 1 at the beginning of pouring the molten metal 1 from the casting container 2 into the mold 3, is calmed and is at the same height with an inside of the mold 3. With the help of the actuator, such as another robot arm or a motor, the mold 3 can be tilted.

As in Fig. 6 1, the casting container 2 may have a pouring opening 18 at a connection point to a casting mold 3. The pouring opening 18 may extend over the entire width of the mold cavity 4.

Furthermore, a movable cover for the pouring opening 18 may be provided. The cover can be a closure flap for the pouring opening 18 or a plate displaceable in the plane of the pouring opening 18. The cover 19 can also as in Fig. 7 The use of a cover has the advantage that the casting container 2 can be correspondingly positioned and aligned with respect to the casting mold 3 before casting, wherein a transfer of the melt is prevented when the pouring spout 18 is closed. After removing the cover, the molten metal 1 can then be poured from the casting container 2 into the casting mold 3.

In the Fig. 7 embodiment illustrated is particularly suitable for the use of inert gas, since after receiving the melt of the casting container 2 closed by means of the lid and the casting container 2 via a filling opening, not shown here, which may for example be closed with a valve, can be filled with inert gas.

According to the in Fig. 8 and 9 illustrated embodiment, the casting container 2 and the mold 3 can be connected to each other, wherein the casting container can be suspended in the mold 3 and locked thereon. The connection between casting container 2 and mold 3 can be positive and / or non-positive.

As in Fig. 9 shown, after connecting the casting container 2 and the mold 3, one of the casting mold 3 facing end face 21 of the casting container 2 extends parallel to an end face 22 of a feeder 23 and is applied to this. The feeder 23 may be formed by a sand mold 24. The end faces 21, 22 of the casting container 2 and feeder 23 and sand mold 24 may correspond to each other with respect to their surfaces and contours. Furthermore, the end faces 21, 22 may be formed congruent to each other. Thus, one of the end faces 21, 22 could have one or more extensions, while the other of the end faces 21, 22 could have corresponding receptacles. The sand mold 24 is often referred to as a "cover core". In the illustrated embodiment, the feeder 23 is part of the pouring system and designed as a so-called open feeder.

An outer surface 26 of the casting container 2 which faces an outer surface 25 of the casting mold 3 and the outer surface 25 may enclose an acute angle, that is to say an angle of less than 90 °, with one another. An inner surface 27 of the pouring container 2 and the outer surface 26 may be parallel to each other.

The casting container 2 may have a pouring edge 28, via which the melt passes into the casting mold 3. The width of the pouring edge 28 may correspond to a width of the feeder 23 and / or a width of the sand mold 24 inserted into the feeder 23. The pouring edge 28 and a pouring edge of the sand mold 24 may be continuously aligned with each other or form a step whose height is less than 10 mm. The pouring edge of the sand mold 24 is for illustrative reasons in Fig. 9 not provided with its own reference number. However, the position of the pouring edge is immediately adjacent to the pouring edge designated by reference numeral 28.

A surface of the sand mold 24 may be flat in a region adjoining its pouring edge and enclose with the end face 22 an angle between 80 and 100 °, preferably an angle between 85 ° and 95 °. As shown in Fig. 9 For example, the angle between the surface of the sand mold and the end face is approximately 90 °.

At a viewed in Eingießrichtung rear portion which merges into a mold cavity, the surface of the sand mold 24 may have a portion having an angle of more than 90 °, preferably an angle of more than 100 ° and less than 160 °, with the enclosing the pouring edge adjacent area of the surface of the sand mold 24. The in the FIGS. 8 and 9 embodiment shown is also very well suited for carrying out the method according to the invention, wherein in the FIGS. 8 and 9 embodiment illustrated in addition, all the device features in the FIGS. 1 to 7 illustrated embodiments may have.

The embodiments show possible embodiments of the solution according to the invention, it being noted at this point that the invention is not limited to the specifically illustrated embodiments thereof. The scope of protection is determined by the wording of the claims.

REFERENCE NUMBERS

1

molten metal

2

gooseneck

3

mold

4

mold cavity

5

bottom section

6

opening

7

pouring

8th

bleed

9

channel

10

channel

11

channel

12

section

13

robot arm

14

contraption

15

sensor

16

control

17

actuator

18

pouring

19

cover

20

light source

21

face

22

face

23

Speiser

24

sandbox

25

outer surface

26

outer surface

27

Inner surface

28

pouring edge

Claims (18)

1. Method for casting a cast component according to the tilt casting principle, wherein metal melt (1) from at least one tiltable casting container (2) is recast in a casting mould (3) with a shaping hollow space (4) which reproduces the cast component and the at least one casting container (2) and the casting mould (3) are arranged beside each other in a step, characterised in that, in a subsequent step, the metal melt (1) is calmed, wherein the at least one casting container (2) and the casting mould are positioned in such a manner that, prior to the recasting of the metal melt (1) from the at least one casting container (2) into the casting mould (3), a calmed level (a) of the metal melt (1) in the at least one casting container (2) is located at the same height as a portion of an inner side of the casting mould (3), wherein the at least one casting container (2) and the casting mould (3) prior to the recasting are positioned in such a manner that the calmed level (a) of the metal melt in the casting container is located at least at the same height as the lowest portion of the shaping hollow space (4), wherein the casting container (2) while being filled with the metal melt is spatially separated from the casting mould (3) and after filling is moved by a robot arm (13) towards the casting mould (3) and fixed with respect to the casting mould (3).
2. Method according to claim 1, characterised in that the at least one casting container (2) is positioned prior to the recasting in such a manner that the calmed level (a) of the metal melt (1) at the beginning of the recasting extends parallel with a wall portion, in particular a base (5), of the casting container (2).
3. Method according to claim 1 or 2, characterised in that the casting container (2) has an incision which opens directly in the shaping hollow space (4) and the shaping hollow space (4) whilst recasting the metal melt (1) is connected via the incision directly to the casting container (2) .
4. Method according to claim 3, characterised in that the incision (8) extends over an entire width of the shaping hollow space (4) facing the casting container (2), wherein a portion of the melt remains in the incision as a feeder volume.
5. Method according to any one of claims 1 to 4, characterised in that the pouring operation of the metal melt (1) is initiated by tilting the casting container (2) in the direction of the casting mould (3), or in that the casting container and the casting mould are rotated together and in the same direction about a common axis in order to initiate the pouring operation.
6. Method according to claim 5, characterised in that the casting container (2) and the casting mould (3) are tilted together and in the same direction during the recasting of the metal melt (1).
7. Method according to any one of claims 1 to 6, characterised in that the casting container (2) which is filled with the metal melt (1) is moved towards the casting mould with a pendulum movement, wherein the pendulum movement is carried out in an opposite direction to oscillations of the metal melt (1).
8. Method according to any one of claims 1 to 7, characterised in that the level of the metal melt is detected by means of at least one sensor.
9. Device (14) for tilt casting having at least one casting container (2) and at least one casting mould (3), wherein the at least one casting container (2) and the at least one casting mould (3) can be connected to each other, wherein in a connected state of the at least one casting container (2) and the at least one casting mould (3) an end face (21) of the at least one casting container (2) facing the at least one casting mould (3) extends parallel with an end face (22) of at least one feeder (23) of the at least one casting mould (3) and is in abutment therewith, wherein the at least one casting container (2) has a pouring edge (28) via which the melt is poured into the at least one casting mould (3), characterised in that the width of the pouring edge (28) corresponds to a width of the feeder (23), wherein the casting container (2) while being filled with the metal melt (1) is spatially separated from the casting mould (3) and the device has at least one robot arm (13) at least for moving the at least one casting container (2) to the at least one casting mould (3) and at least one sensor (15) for detecting a level of the metal melt (1) in the casting container (2) and at least one control unit (16) which is connected to the at least one sensor (15) and which is configured to control the robot arm (13) in accordance with signals produced by the at least one sensor (15), the control unit (16) is configured to control the movement of the robot arm (13) and an actuator (17) for actuating the casting mould (3) in such a manner that the level of the metal melt (1) at the beginning of a recasting of the metal melt (1) from the casting container (2) into the casting mould (3) is calmed and is located at the same height as an inner side of the casting mould (3).
10. Device according to claim 9, characterised in that the end faces (21, 22) of the casting container (2) and feeder correspond to each other with respect to the faces and contours thereof.
11. Device according to claim 9 or 10, characterised in that an outer face (26) of the at least one casting container (2) which faces an outer face (25) of the at least one casting mould (3) and the outer face (25) of the at least one casting mould (3) form an acute angle with each other.
12. Device according to claim 11, characterised in that an inner surface (27) of the at least one casting container (2) and the outer face (26) of the at least one casting container (2) extend parallel with each other.
13. Device according to any one of claims 9 to 12, characterised in that the pouring edge (28) of the at least one casting container (2) and a pouring edge of the feeder (23) are steplessly in alignment with each other or form a step whose height is less than 10% of a height of the feeder (23) which extends transversely relative to the pouring edge and parallel with the end face.
14. Device according to claim 13, characterised in that a surface of the feeder (23) is constructed in a planar manner in a region adjacent to the pouring edge thereof and forms with the end face (22) of the feeder an angle between 80 and 100°, preferably an angle between 85° and 95°.
15. Device according to claim 14, characterised in that the at least one feeder (23) at a rear portion of the surface when viewed in a pouring direction has a portion which forms an angle of more than 90°, preferably an angle of more than 100° and less than 160°, with the region of the surface of the feeder (23) which is adjacent to the pouring edge.
16. Device according to any one of claims 9 to 15, characterised in that the feeder (23) is formed by means of at least one sand mould (24).
17. Device according to claim 16, characterised in that the casting container (2) at a connection location with respect to the casting mould (3) has a pouring opening (18), wherein a movable cover (19) for the pouring opening is provided.
18. Device according to claim 17, characterised in that the cover is constructed as a lid, which is articulated to the casting container (2) so as to be able to be pivoted or lifted.

Images