Casting machine and casting method

Abstract

The invention relates to a casting machine and a method for pouring a melt into a casting mould, in which at least one casting mould (24) is accommodated on a support of the casting machine, in which the melt (34) is filled into the casting mould by means of a crucible (25) of the casting machine, in which the casting mould is moved by means of a pivoting device of the casting machine when the melt is filled into the casting mould and is inclined about an axis (32), wherein the crucible is moved by a robot of the casting machine when the melt is filled into the casting mold, the movement of the casting mold when the melt is filled into the casting mold is detected by a sensor device of the casting machine, and the crucible is moved by the robot as a function of the movement of the casting mold.

Description

Technical Field

[0001] The invention relates to a casting machine and a method for pouring a melt into a casting mold, wherein at least one casting mold is accommodated on a support of the casting machine, wherein the melt is guided into the casting mold via a crucible of the casting machine, wherein the casting mold is moved and tilted about an axis by a pivot device of the casting machine when the melt is filled into the casting mold, and wherein the crucible is moved by a robot of the casting machine when the melt is filled into the casting mold. Background Art

[0002] Such casting machines and methods are well known in the prior art, wherein during casting liquid metal is always filled into the casting mold until the casting mold or the cavity of the casting mold is completely filled. After the melt solidifies, the subsequently formed component can be formed or removed from the casting mold. The casting mold can be a permanent mold or a disposable mold, such as a permanent mold or a sand mold. It is important that when the melt is filled into the casting mold (this can be done by a crucible), the casting mold moves or tilts around an axis. For this purpose, the casting mold is arranged on a movable support of the casting machine. The support of the casting machine is designed so that the casting mold can be moved or tilted around an axis by a pivot device. By tilting the casting mold when pouring the melt, depending on the shape of the cavity in the casting mold, the casting mold can be completely filled with metal without forming air pockets, cold flows, contaminants, etc. in the casting mold.

[0003] The melt is poured into the mold or the pouring gate of the mold by a robot, which fills the melt into a crucible, positions it at or above the pouring gate, and tilts the crucible in such a way that the melt flows into the pouring gate in a desired amount. The robot can be, for example, a multi-axis robot with a robot arm fastened with a crucible. The robot can fill the crucible in the molten pool and move it to the mold. The robot is regularly programmed here so that the robot arm with the crucible follows the pivoting movement of the mold, so that even if the mold is tilted, the melt is always filled into the pouring gate or can flow into it. Alternatively, an additional fixed crucible or melt reservoir can be set on the mold, and the melt reservoir fills the crucible with liquid metal by the robot. When the mold is tilted, the melt will flow into the pouring gate of the mold from the melt reservoir firmly fastened to the mold.

[0004] However, as has already been shown, the melt must have a significantly higher temperature, since there is a temperature loss when the melt is decanted. In addition, the decanting step prolongs the pouring cycle. It also promotes the formation of an oxide layer on the surface of the melt and the introduction of oxides, which can deteriorate the quality of the product produced by casting. In addition, the positioning of the crucible directly at the pouring gate using a robot is difficult to achieve, since the movement of the crucible or the robot must always be very precisely coordinated with the position of the crucible or the pouring gate, which is firmly located on the mold. Summary of the invention

[0005] The object of the present invention is therefore to provide a method for pouring a melt into a casting mold and a casting machine which allow cost-effective casting of high-quality products.

[0006] This object is achieved by a method having the features of claim 1 and a casting machine having the features of claim 13 .

[0007] In the method for pouring a melt into a casting mold according to the present invention, at least one casting mold is accommodated on a support of a casting machine, wherein the melt is filled into the casting mold through a crucible of the casting machine, wherein the casting mold is moved and tilted about at least one axis by a pivot device of the casting machine when the melt is filled into the casting mold, wherein the crucible is moved by a robot of the casting machine when the melt is filled into the casting mold, wherein the movement of the casting mold when the melt is filled into the casting mold is detected by a sensor device of the casting machine, and wherein the crucible is moved by the robot according to the movement of the casting mold.

[0008] In the method according to the invention, it is provided that when the melt is poured into the casting mold, that is, during the casting process, the casting machine tilts or pivots the casting mold about at least one axis. As a result, the metal or melt flowing into the casting mold can continuously fill the casting mold without causing uncontrolled filling of the cavity in the casting mold, in this case. In order to prevent the melt from having to be transferred into the casting mold by a robot, resulting in an increase in oxides in the melt due to turbulence and the melt having to be provided at high temperatures, now according to the invention, the sensor device of the casting machine detects the movement of the casting mold when the melt is poured into the casting mold. This can move the crucible by the robot according to the detected movement of the mold, and thus relatively accurately track the tilting movement of the mold. In the simplest embodiment, the casting mold is tilted about at least one axis. Then the robot of the casting machine can be designed so that the crucible can be moved by the robot in at least two degrees of freedom. Then the crucible can be positioned directly at or above the gate of the casting mold, so that it is no longer necessary to transfer the melt to the crucible located on the mold. In this way, it is no longer necessary to significantly increase the temperature of the melt, and the transfer step can be omitted, which otherwise prolongs the casting process. Key to the execution of the method is a sensor arrangement which detects the movement of the mould so that the robot can locally and precisely position the crucible according to the movement of the mould and follow this movement.

[0009] When the mold is tilted around an axis, the crucible can be stationary relative to the mold, or the crucible can be tilted around another axis. In order to fill the melt into the mold or the pouring gate, the crucible filled with the melt or liquid metal can be positioned at the pouring gate in the mold. In a first embodiment of the method, it can be provided that the crucible is firmly fixed relative to the mold, or the crucible is moved as the mold is moved by the robot in a manner that the relative movement of the mold and the crucible does not occur. Due to the movement of the mold, the crucible moves therewith, so that the melt can be poured into the pouring gate by this movement. According to another embodiment, the crucible can be tilted around another axis. This means that during the movement of the mold when the melt is poured into the pouring gate, the crucible can move relative to the mold, so that more or less melt can be poured into the pouring gate compared to the stationary crucible. The melt flow rate or melt volume flow rate can thus be adjusted, for example, according to the shape of the cavity. The casting process can better adapt to the shape of the product.

[0010] The tilting of the mold around the axis and / or the movement of the robot can be controlled using a control device of the casting machine. The control device can include a device for data processing, such as a computer or a programmable logic controller, or be formed by a device for data processing. As part of the casting process, the control device can then control, for example, a motor, an actuator or other actuator so that the mold is tilted or pivoted around at least one axis. In addition, the control device can also control the robot so that the crucible is moved by the robot according to the movement of the mold. Sensor devices can be used here to determine the movement or position of the mold.

[0011] The sensor device can be used to determine the absolute position, rotation angle and / or rotation speed of the axis of the mold and / or the movement of the crucible. The pivot device can have a sensor device, and the sensor device can include, for example, a rotary encoder or other suitable sensors on the corresponding axis. These sensors can then determine the actual position of the axis of the mold or the tilt angle of the mold and thus the position of the gate of the mold independently of the drive of the pivot device for tilting the mold. It is also advantageous if the rotation speed of the mold can be determined by the sensor device, because in this way the crucible can be adapted to the rotation speed by the movement of the robot by the control device, and in particular to the acceleration of the mold during tilting.

[0012] During the filling, the regulating device of the control device can regulate the movement of the crucible as a reference variable, depending on the absolute position, the angle of rotation or the rotation speed of the casting mold. The regulating device can be designed in the control device as a regulating system that regulates the drive of the robot so that the crucible moves in the desired manner during the casting process. It can also be provided that the regulating device regulates the tilting of the casting mold, for example, as a function of the rotation speed. The regulating device can then have a further regulating system.

[0013] By means of the sensors of the sensor device, a touch contact between the casting mold and the crucible can be detected when the melt is poured into the casting mold. By detecting the touch contact, it is also possible to detect the movement of the casting mold when the melt is poured into the casting mold. This enables the crucible to follow the movement of the casting mold particularly accurately. The sensor here can be any sensor that is suitable for detecting touch contact.

[0014] The touch contact between the mold and the crucible can be formed in a predetermined contact area, preferably adjacent to the pouring gate of the mold. It can be provided that the crucible is moved to the mold by the robot so that the touch contact between the mold and the crucible occurs before the melt is poured into the mold. The contact area can be formed so that specially provided contact surfaces, protrusions, recesses, certain geometric shapes corresponding to each other, etc. are formed on the mold and / or the crucible. If the contact area is formed at the pouring gate or in the area directly surrounding the pouring gate, it is ensured that the crucible can be positioned in the correct position at the pouring gate.

[0015] The sensor can detect the force and / or torque during contact. For this purpose, the sensor can be positioned on the robot, the crucible or the casting mold. The sensor can be used to measure the force or torque so that the crucible can track the casting mold by the robot according to the measured dimensions. The movement of the robot can thereby be regulated relatively accurately. Alternatively, the sensor can be used to measure the direction of the force or torque.

[0016] Alternatively, the relative distance between the mold and the crucible can be detected by the sensor of the sensor device, whereby the crucible and the mold can be moved without contact during the filling of the melt into the mold. This means that when pouring the melt, the crucible and the mold do not touch each other and always form a relative distance, which is preferably always of the same size. Therefore, the sensor can be designed to detect the approach of the crucible to the mold. During the casting process, the crucible can initially be moved to the mold by the robot until the desired relative distance is reached. When the mold is tilted, the robot can now track the movement of the crucible to the mold so that the relative distance is always the same. The advantage of this is that there is no mechanical contact between the crucible and the mold, which can prevent possible damage.

[0017] The regulating device of the control device can regulate the movement of the crucible during the filling process according to the relative distance, force and / or torque. The relative distance, force and / or torque can then be a reference variable, according to which the regulating device regulates the movement of the robot or the crucible. This ensures that the crucible is always in the desired position during the casting process.

[0018] The crucible can be releasably fixed to the mold, wherein the mold can then be moved, and the movement caused on the robot can be detected by the sensors of the sensor device, wherein the crucible can track the movement of the mold by the robot. The releasable fixation can be formed simply by a form-fitting connection between the crucible and the mold, for example by the robot hooking the crucible on the mold. However, the robot always remains firmly connected to the crucible here, so that subsequent movements of the mold also lead to movements of the robot. In this case, the sensor of the sensor device is a component of the robot, by which the force on the robot or the crucible caused by the movement of the mold is detected. Then, depending on the force exerted on the robot by the crucible, the drive of the robot can move the robot so that the crucible follows the movement of the mold. The advantage here is that no particularly complex programming of the robot or the control device is required. Here, the robot with the crucible only needs to be moved to a point in space to connect it to the mold.

[0019] The control device can use the sensor device to determine the volume of the melt located in the crucible. In principle, the control device can also calculate the total melt volume in the casting mold within the corresponding time period. The sensor device can initially be set to measure the weight of the crucible. By reducing the weight during the casting process, the melt volume can be recalculated at any time. This is also particularly advantageous if the volume of the mold cavity is known. The control device can then also determine the time point until the casting process is completed or the time period for pouring the melt into the casting mold is completed. This can further speed up the casting process.

[0020] During filling, the mold can be tilted around a second axis by a pivot device, wherein the axis is designed to extend laterally relative to the second axis. Thus, it can be provided that when pouring the melt, the mold is tilted or rotated around the axis or the first axis and around the second axis. Thus, the two axes can be designed or arranged to extend laterally relative to each other, so the mold can move in two planes, resulting in movement in three dimensions during filling of the melt. This can adapt the movement of the mold to the cavity formed in the mold individually during filling of the melt. Even products with complex geometries can be cast with high quality. When pouring the melt into the mold, the melt can be guided to the desired flow direction by moving the mold, which flow direction can change according to the shape of the product during the casting process or filling, and can be adapted to the shape of the product. The melt channel formed in the mold can also be considered here. The casting process can be designed here so that the mold cavity of the mold is filled smoothly and completely, thereby avoiding air inclusions and cold flow tendencies and product contamination by oxides. In addition, the arrangement of the cavity in the mold is no longer necessarily limited to the optimal position of the gate on the mold. Since the casting mold can be moved with two degrees of freedom, the arrangement of the cavities is more flexible. Depending on the shape of the product to be cast, the size of the casting mold can be made smaller because the arrangement of the cavities in the casting mold can be selected in the most space-saving way possible.

[0021] The casting machine according to the invention for pouring a melt into a casting mold comprises a support on which at least one casting mold and a crucible are accommodated, wherein the casting mold can be filled with melt by means of the crucible, wherein the casting machine comprises a pivoting device by means of which the casting mold can be moved and tilted about an axis when the melt is filled into the casting mold, wherein the casting machine comprises a robot by which the crucible can be moved during the filling of the melt into the casting mold, wherein the casting machine has a sensor device by means of which the movement of the casting mold can be detected during the filling of the melt into the casting mold, wherein the crucible can be moved by the robot in dependence on the movement of the casting mold. With regard to the advantageous effects of the casting machine according to the invention, reference is made to the description of the advantages of the method according to the invention.

[0022] The sensor device may comprise at least one sensor, in particular a force sensor, a displacement sensor, a rotation sensor, an image sensor, an inductive sensor, a capacitive sensor, a near-field sensor, an ultrasonic sensor, a radar sensor, a magnetic sensor. In principle, the sensor may be any sensor suitable for detecting the movement of the casting mould during the filling with the melt. Furthermore, the sensor device may also comprise a plurality of sensors of the same or different types. The force sensor may be a strain gauge or a piezoelectric sensor. The displacement sensor may be an optical sensor or a rotary encoder. The image sensor may be constituted, for example, by a video camera. The near-field sensor may be formed by an inductive sensor or a capacitive sensor. Ultrasonic sensors or radar sensors, which can easily measure distances, may also be used. Magnetic sensors are also suitable for measuring proximity or touch contact.

[0023] The sensor can be positioned away from the mold, on the mold, on the crucible or on the robot, preferably adjacent to the gate or directly on the gate. It is advantageous if the sensor is not arranged directly on the mold, because the sensor is independent of the mold. The sensor can also be arranged and aligned on a support of the casting machine so that it is positioned adjacent to the gate, for example a camera with an optical detection range aimed at the gate. The camera can then be used to determine the relative distance between the gate and the crucible. Alternatively or additionally, the sensor can also be arranged directly on the mold or the crucible. The contact of the crucible and the mold in the gate area can then be detected particularly easily.

[0024] The robot may be a multi-axis articulated arm robot. Such a robot, for example a robot with three degrees of freedom, is readily and relatively cheaply available on the market, so there is no need to produce a robot that can be used specifically for a casting machine.

[0025] Further advantageous embodiments of the casting machine result from the characterizing features of the dependent claims associated with method claim 1 . BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Preferred embodiments of the present invention are explained in more detail below with reference to the accompanying drawings.

[0027] In the attached figure:

[0028] Figure 1 shows a perspective view of a crucible of a first embodiment;

[0029] Figure 2 Shows Figure 1 Schematic diagram of possible movements of the crucible;

[0030] Figure 3 shows a perspective view of a crucible of a second embodiment;

[0031] Figure 4 Shows Figure 3 Schematic diagram of possible movements of the crucible;

[0032] Figure 5a-5e A schematic diagram showing a method sequence for filling a casting mold according to a first embodiment;

[0033] Figure 6a-6e A schematic diagram of the method sequence for filling a casting mold according to a second embodiment is shown. DETAILED DESCRIPTION

[0034] Figure 1 and Figure 2 The schematic diagram of the present invention shows a first embodiment of a crucible 10 for a casting machine (not shown here) and a method performed therewith. The crucible 10 is connected to a robot arm (not shown here) of the casting machine via a receiving portion 11 and can be pivoted about at least one axis 12 via the robot arm. When the crucible 10 is pivoted about the axis 12, the melt in the receiving space 13 of the crucible 10 can enter the pouring gate (not shown here) of the casting mold via the pouring collar 14. In addition, a contact surface 15 is provided on the pouring collar 14 of the crucible 10, by which the crucible 10 can contact the pouring gate 15 of the casting mold. Figure 2 16 schematically shown in FIG. 1 . A pouring gate (not shown here) is formed on the casting mold 16, and the crucible 10 is pivoted about the axis 12 by a robot arm or a robot in order to fill the melt into the pouring gate of the casting mold 16. In the region of the contact surface 15, a sensor (not shown here), in particular a force sensor of a sensor device of a casting machine, is provided, with which the contact between the crucible 10 and the casting mold 16 can be detected. By means of a control device of the casting machine, the crucible 10 can be moved by the robot in accordance with a touch contact or movement of the casting mold 16. This ensures that the crucible 10 is always in contact with the casting mold 16 and that the melt can be filled into the casting mold 16 in a desired manner during the casting process.

[0035] Figure 3 and Figure 4The schematic diagram of the crucible 17 is shown, which is connected to a robot arm (not shown here) via a receiving portion 18. The crucible 17 can be tilted about an axis 19 and forms a receiving space 20 for the melt. Figure 1 and Figure 2 In contrast to the crucible shown, a sensor 21 is provided here for detecting the force. Figure 4 If the casting mold 22 schematically shown in the figure is in contact with the crucible 17, the sensor 21 detects the force regardless of the exact position of the crucible 17 on the contact surface 23. Here, the force detected by the sensor device of the casting machine can also be used to move the crucible 17 by the robot arm according to the movement of the casting mold 22.

[0036] Figure 5a to Figure 5e , shows a casting process in outline, wherein a casting mold 24 and a crucible 25 are schematically shown. The casting mold 24 is formed by an upper mold part 26 and a lower mold part 27. A pouring gate 28 is also formed on the casting mold 24, which has a melt channel 29 of a runner 30 leading to a cavity 31. The casting mold 24 is designed to be tiltable about at least one axis 52 by a pivot device of the casting machine (not shown here). The crucible 25 can also be designed to be tiltable about an axis 33. For this purpose, the crucible can be moved while the melt 34 is poured into the casting mold 24 by a robot of the casting machine (not shown here). The movement of the crucible 25 can take place in at least two degrees of freedom.

[0037] Figure 5a to Figure 5e The schematic diagram shows a casting mold 24 with a crucible 25 during different time periods according to an embodiment of the casting process. During the casting process, the crucible 25 is always in contact with the casting mold 24 at the pouring gate 28. Figure 5a Starting from the starting position shown, the crucible 25 is aligned relative to the mold 24 by a robot arm (not shown here) and positioned on the pouring gate 28. The robot arm and / or the crucible 25 are equipped with sensor devices, which are not shown in more detail and correspond to the above. Figure 4 Functional principle shown. By means of the sensor device, forces acting on the crucible 25 , in particular forces acting on the crucible 25 by the melt 34 located in the crucible and the pressure acting on the casting mold 24 , can be detected.

[0038] like Figure 5b As shown, the casting mold 24 is now tilted about the axis 32 so that the melt 34 in the crucible 25 flows toward the gate 28 and continues to flow into the cavity 31, as shown in FIG. Figure 5c The tilting movement of the casting mold 24 results in a spatial displacement of the pouring gate 28, wherein the crucible 25 always follows the pouring gate 28 via the robot arm. At the same time, the crucible 25 is tilted about the axis 33. The fact that the crucible 25 is resting on the casting mold 24 can be determined by a sensor device. Figure 5dThe crucible 25 is subjected to a force acting laterally via the casting mold 24, which is also detected via the sensor device. Figure 5e As shown, the casting mold 24 is eventually completely filled with the melt 34 .

[0039] Figures 6a to 6e The schematic diagram of FIG. 1 shows a casting mold 35 with a crucible 36 according to another embodiment of a casting process during different time periods. Figures 5a to 5e In contrast to the illustration in FIG. 3 , the sensor arrangement here comprises a sensor 37 arranged directly on the crucible 36. This results in a configuration of the casting mold 35 and the crucible 36 such as Figure 2 As shown in the schematic diagram in FIG. By means of sensor 37, direct touch contact between mold 35 and crucible 36 can be detected. Figures 6a to 6c As can be seen in the figure, during the casting process the mold 35 is tilted simultaneously about the axis 38 and the crucible 36 about the axis 39. The crucible 36 always tracks the casting mold 35. This is done by a control device that moves the crucible 36 to maintain touching contact. This is also the case for the entire casting process until the melt 40 is finally poured into the casting mold 35.

Claims

1. A method for pouring a melt into a casting mold, wherein at least one casting mold (16, 22, 24, 35) is accommodated on a support of a casting machine, wherein the melt (34, 40) is filled into the casting mold via a crucible (10, 17, 25, 36) of the casting machine, wherein the casting mold is moved and tilted about an axis (32, 38) by a pivot device of the casting machine when the melt is filled into the casting mold, wherein the crucible is moved by a robot of the casting machine when the melt is filled into the casting mold, It is characterized in that The movement of the casting mold while the melt is being filled into the casting mold is detected by a sensor device of the casting machine, wherein the crucible is moved by the robot in accordance with the movement of the casting mold.

2. The method according to claim 1, characterized in that The crucible (10, 17, 25, 36) is stationary relative to the casting mold (16, 22, 24, 35) when the casting mold (16, 22, 24, 35) is tilted about an axis (32, 38), or the crucible is tilted about another axis (12, 19, 33, 39).

3. The method according to claim 1 or 2, characterized in that: The tilting of the casting mold (16, 22, 24, 35) about the axis (32, 38) and / or the movement of the robot are controlled by a control device of the casting machine.

4. The method according to claim 3, characterized in that The absolute position, the rotation angle and / or the rotation speed of an axis (32, 38) of a casting mold (16, 22, 24, 35) and / or a movement of a crucible (10, 17, 25, 36) are determined by means of a sensor device.

5. The method according to claim 4, characterized in that The regulating device of the control device regulates the movement of the crucible (10, 17, 25, 36) during filling as a function of the absolute position, the angle of rotation and / or the speed of rotation of the casting mold (16, 22, 24, 35) as a reference variable.

6. The method according to any one of the preceding claims, characterized in that Touch contact between a casting mold (16, 22, 24, 35) and a crucible (10, 17, 25, 36) is detected by sensors (21, 37) of the sensor device during filling of the casting mold with melt (34, 40).

7. The method according to claim 6, characterized in that The touching contact between the casting mold (16, 22, 24, 35) and the crucible (10, 17, 25, 36) is in a predetermined contact area (15, 23), preferably adjacent to the gate (28) of the casting mold.

8. The method according to claim 6 or 7, characterized in that: The sensor (21, 37) detects force and / or torque during touch contact.

9. The method according to any one of claims 3 to 5, characterized in that The relative distance between casting mold and crucible is detected by sensors of the sensor device, wherein the movement of crucible and casting mold takes place without contact while the casting mold is being filled with melt.

10. The method according to claim 8 or 9, characterized in that: The regulating device of the control device regulates the movement of the crucible during filling as a function of the relative distance, force and / or torque.

11. The method according to any one of claims 3 to 5, characterized in that The crucible is releasably fastened to the casting mold, and the casting mold is subsequently moved, whereby the movement caused on the robot is detected by sensors of the sensor device, wherein the crucible tracks the movement of the casting mold via the robot.

12. The method according to any one of claims 3 to 11, characterized in that The control device determines the volume of the melt in the crucible (10, 17, 25, 36) by means of a sensor device.

13. A casting machine for pouring a melt into a casting mold, wherein the casting machine comprises a support on which at least one casting mold (16, 22, 24, 35) and a crucible (10, 17, 25, 36) are accommodated, wherein the melt (34, 40) can be filled into the casting mold via the crucible, wherein the casting machine comprises a pivoting device by which the casting mold can be moved and tilted about an axis (32, 38) when the melt is filled into the casting mold, wherein the casting machine comprises a robot by which the crucible can be moved during the filling of the melt into the casting mold, It is characterized in that The casting machine has a sensor device, by means of which a movement of the casting mold can be detected during the filling of the casting mold with melt, wherein the crucible can be moved by the robot as a function of the movement of the casting mold.

14. The casting machine according to claim 13, characterized in that The sensor device comprises at least one sensor (21, 37), in particular a force sensor, a displacement sensor, a rotation sensor, an image sensor, an inductive sensor, a capacitive sensor, a near-field sensor, an ultrasonic sensor, a radar sensor, a magnetic sensor.

15. The casting machine according to claim 14, characterized in that The sensor (21, 37) is positioned remote from the casting mold (24), on the casting mold (35), on the crucible or on the robot, preferably adjacent to the pouring gate or directly at the pouring gate (28).

16. A casting machine according to any one of claims 13 to 15, characterised in that The robot is a multi-axis articulated arm robot.

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