CASTING TOOL, FOR EXAMPLE CORE SHOOTING TOOL OR PERMANENT MOULD, AND CORRESPONDING CASTING METHOD

Abstract

A casting tool, for example a core shooting tool or a permanent mould, having an upper tool part and a lower tool part, which on opposite sides each have at least one engraving formed as a shell engraving and which form a mould cavity, characterized in that the shell engraving on an outer side facing away from the mould cavity comprises at least one physical sensor which is configured to measure a physical quantity with respect to a material accommodated in the mould cavity. Furthermore, a corresponding casting method is described.

Claims

1. A casting tool comprising an upper tool part and a lower tool part, which on opposite sides each have at least one engraving formed as a shell engraving and which form a mould cavity, wherein the shell engraving on an outer side facing away from the mould cavity includes at least one physical sensor which is configured to measure a physical quantity with respect to a material accommodated in the mould cavity.

2. The casting tool according to claim 1, in which the physical sensor comprises a temperature sensor thermally coupled to the shell engraving, wherein the casting tool has at least one heating element thermally coupled to the shell engraving and a control unit which is configured to adjust a heating power of the heating element depending on a measurement signal from the temperature sensor.

3. The casting tool according to claim 1, in which the physical sensor comprises a density sensor mechanically coupled to the shell engraving for determining the density of a material shot into the mould cavity, wherein the control unit is configured to adjust the heating power of the heating element depending on a measurement signal from the density sensor.

4. The casting tool according to claim 1, in which the shell engraving has a wall thickness at least in the area of a measuring field of the sensor between 0.5 and 15 mm, preferably between 0.5 and 10 mm and especially preferably between 0.5 and 3 mm.

5. The casting tool according to claim 1, in which a multi-channel mould venting system for venting the mould cavity is connected to the shell engraving at different positions, wherein the mould venting system may comprise multiple air pressure sensors which measure a respective venting pressure of the mould cavity at the different positions.

6. The casting tool according claim 5, in which the mould venting system also includes a valve block with multiple independently controllable valves, each valve being fluidically connected to one of the other positions via an air line, wherein the control unit is configured to control an opening degree of at least one of the valves, depending on at least one measurement signal of the air pressure sensors.

7. The casting tool according to claim 5, in which a multi-channel mould ventilation system is connected to the shell engraving to selectively apply pressure to the mould cavity at different positions of the mould cavity, wherein the mould ventilation system includes a valve block with multiple independently controllable valves and each valve is fluidically connected to one of the other positions via an air line.

8. The casting tool according to claim 1, in which the at least one heating element is thermally coupled to a raised contour of the plate, which corresponds at least in sections to a contour of the shell engraving.

9. The casting tool according to claim 8, in which the heating element has a geometry that reproduces a raised contour of the plate on its side opposite the shell engraving.

10. The casting tool according to claim 1, the casting tool having an ejection system configured to deform the shell engraving between an initial geometry and an ejection geometry.

11. The casting tool according to claim 8 in which the plate, preferably the shell engraving of the plate, consists in sections of a first material and in sections of a second material, the two materials having different moduli of elasticity.

12. The casting tool according to claim 1, in which the shell engraving has a surface coating on an inner side facing the mould cavity which reduces the adhesion between the shell engraving and the material accommodated in the mould cavity.

13. The casting tool according to claim 1, in which the casting tool is a core shooting tool or a permanent mould.

14. A casting method, comprising: providing a casting tool according to claim 1 and shooting a flowable and curable material, such as a binder-added mould base material, into the mould cavity under a shooting pressure, wherein the shell engraving is heated with a heating element; and measuring a physical quantity of the material shooting into the mould cavity, such as a temperature of the shell engraving when shooting, and adjusting a heating power of the heating element, depending on the measured temperature.

15. The casting method according to claim 14, in which, when shooting, a density of the shot material can be measured and, depending on the measured density, the heating power of the heating element can be adjusted.

16. The casting method according to claim 14, in which, when shooting, the mould cavity is vented at different positions by means of a multi-channel mould venting system and a respective venting pressure of the mould cavity is measured at the different positions by air pressure sensors.

17. The casting method according to claim 16, in which, depending on at least one measurement signal from the air pressure sensors, an opening degree of at least one valve that is fluidically connected to one of the positions via an air line can be controlled.

18. The casting method according to claim 14, in which, after shooting and cooling the casting tool, a moulded casting arranged and formed in the mould cavity is ejected from the mould cavity by means of a mould ventilation system, for which purpose the mould ventilation system applies an air pressure to the casting via a valve block with multiple independently controllable valves, each of which is fluidically connected via an air line to one other position of the mould cavity.

Description

DRAWING

[0032] The drawing described herein is for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0033] FIG. 1 shows an exploded view of an exemplary embodiment of a casting tool according to the invention, which is designed as a core shooting tool.

DETAILED DESCRIPTION

[0034] Example embodiments will now be described more fully with reference to the accompanying drawing.

[0035] The core shooting tool 1 has a upper tool part 2 and a lower tool part 3, which are accommodated in a two-part core box 17 and each have a shell engraving 4 on opposite sides. For the core shooting tool 1 shown in an exploded view, the shell engravings 4 of the upper tool part 2 and the lower tool part 3 form a mould cavity 5 in a joined state, said mould cavity 5 being formed between the upper tool part 2 and the lower tool part 3 and representing the core mould. The upper shell engraving 4 depicted in the figure has several temperature sensors 7 thermally contacted with the shell engraving 4 on an outer side 6 facing away from the mould cavity 5 and two heating elements 8 thermally contacted with the shell engraving 4. A control unit 9 is configured to adjust the heating power of the heating elements 8 depending on a measurement signal from the temperature sensors 7, e.g., in such a way that a constant process temperature is maintained, or in such a way, that a local temperature increase is achieved, which locally increases the flowability of the shot material.

[0036] The core shooting tool further has a core density sensor 10, whose measurement signal is also evaluated by the control unit 9 and used to adjust the heating power of the heating element 8 as required. A suitable core density sensor 10, for example, is an ultrasonic sensor.

[0037] The upper tool part 2 and the lower tool part 3 are designed as plates 11, which have the shell engraving 4. The thickness of the plate 11 is considerably less than a depth of the shell engraving 4, which results in a raised contour 12 being formed on the outer side 6 facing away from the mould cavity 5, which is negative to a contour of the shell engraving 4 delimiting the mould cavity.

[0038] The core shooting tool 1 also has a mould venting system 13, which is connected to the plates 11, especially in the area of the shell engraving 4. The mould venting system serves to vent the mould cavity 5 in a defined manner during the shooting of the mould base material mixed with the binder, so that a uniform filling of the mould cavity 5 with the mould base material is achieved and thus the density of the core is as homogeneous as possible. The mould venting system 13 has several air pressure sensors 14 which measure the respective venting pressure of the mould cavity 5 at the different positions of the mould cavity.

[0039] The mould venting system also has a valve block 16 with several independently controllable valves. Each of the valves is fluidically connected to one of the other positions of the mould cavity 5 via a separate air line 15. For this purpose, the shell engraving 4 can have through holes to which the air lines 15 are connected. The control unit 9 can be configured to control an opening degree of at least one of the valves depending on at least one measurement signal of the air pressure sensors 14, e.g., with the proviso that the mould cavity 5 is filled as uniformly as possible with the mould base material during shooting.

[0040] The mould venting system 13 may also function as a mould ventilation system for selectively applying air pressure to mould cavity 5 at different positions in mould cavity 5. For example, mould ventilation can be used to eject the core from the mould cavity 5 after the mould base material has been shot into and solidified, that is after the core has formed in the mould cavity 5.

[0041] Due to the shell design, an efficient core shooting tool is realized since the heat capacity of the core shooting tool is reduced compared to conventional tools. Conversely, the lower heat capacity of the shell core tool also means that heat can be transferred from outside the core shooting tool into the cavity of the core shooting tool without a long time delay and with comparatively low heating power. By using a heater it is possible to vary the core properties. With the help of temperature and core density sensors a continuous quality assurance can be realized in-situ.

[0042] The features of the invention disclosed in the above description, in the drawings and in the claims may be essential to the realisation of the invention, either individually or in any combination.

[0043] Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

[0044] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.