EP0731741B1 - Installation and method for producing ready-to-use casting shells or core assemblies - Google Patents

Abstract

The invention concerns an installation for the production of ready-to-use casting shells or core assemblies, comprising at least two linearly aligned core-shooting machines or stations (1), the core-shooting machines (1) having two tool assemblies (4) which differ from each other at least slightly and which each comprise an upper tool (2) and a lower tool (3), plus identical transfer elements (5) which act as the lower tool (3) of the first core-shooting machine (1) and also convey the core (6) or core assembly along a transfer track (7) through the installation. In order to reduce the space required while ensuring an extremely simple construction, the installation is designed in such a way that the tools being used (2, 3) of the first tool assembly (4) are exchanged for tools (2, 3) of the second tool assembly (4) at the first core-shooting machine (1) after the transfer element (5) has left the first core-shooting machine with the first core (6). The tools being used (2, 3) of the first tool assembly (4) are exchanged for tools (2, 3) of the second tool assembly (4) at the second core-shooting machine (1) after the transfer element (5) has left the second core-shooting machine with the first and second cores (6), etc., until the tools (2, 3) of the tool assembly (4) at the last core-shooting station have been exchanged, so that only cores (6) produced by the same tool assembly (4) are set down on a transfer element (5). The invention also concerns a method using the installation.

Description

The invention relates to a device for producing ready-to-cast masks or core packages, with at least two linearly arranged core shooting machines or shooting stations, wherein the core shooting machines have two tool sets, each consisting of an upper part and a lower part, which differ at least slightly, and identical transfer parts, on the one hand, as a lower part of the first core shooting machine and on the other hand, to transport the core or core package on a transfer path through the device. Furthermore, the invention relates to a method for producing ready-to-cast masks or core packages with a device according to the invention.

Basically, the present invention relates to the field of foundry technology. For casting molded parts, foundry cores or molds are usually produced in separate parts, brought together and connected to one another to form a mold or core package. These core packages are then filled with molten metal to produce, for example, a metallic workpiece, the series of core packages to be filled with molten metal passing through the production line one after the other.

Devices for producing core packages of the type in question are already known from numerous publications. Reference is made to DE-OS 23 04 564 only by way of example. It is also known from practice to manufacture the cores to be connected to form a core package in a production line with a plurality of core shooting machines or shooting stations, the core package being added to each shooting station Core is supplemented. For this purpose, the cores are placed on a transfer part passing through the individual shooting stations, this transfer part mostly serving at the same time as the lower tool part of the first shooting station.

Now the core sands used to manufacture the core packages are always mixed with binding agents, which means that the tools - upper and lower parts of the tools - are heavily contaminated. Accordingly, the tools have to be cleaned after a certain number of cycles and replaced at the shooting stations. However, such a tool change is extremely problematic in practice, since the tools of the individual shooting stations and thus the cores manufactured there are exactly matched to one another. In other words, the contours of the cores of a tool set to be stacked are coordinated with one another in such a way that they lie positively against one another during stacking. If there were even the slightest deviations in the contours of the surfaces of the cores to be stacked, such tensions would occur during stacking that the cores would break with the greatest probability.

If, in the known device, a tool set is replaced due to contamination that has occurred, the transfer parts located in the line with the cores already produced on them must be removed as a whole, since a further packaging with cores manufactured by the exchanged tool set must be carried out due to the least Deviations in the contours of the tool surfaces and thus also the surfaces of the cores then produced from the cores already produced are no longer possible for the reasons already mentioned. In other words, it is always necessary in the known device to restart the entire production line after the tool has been changed and remove or discard cores in the production line. Apart from the waste of material due to the reject parts, this causes a considerable loss of time and thus considerably reduces the capacity of the production line, which in turn increases the costs per core package considerably.

The applicant has already addressed the above problem by proposing a device and a method according to German patent application P 43 18 259.3-24 - this is a post-published state of the art - according to which the tools of a tool set are used jointly, ie simultaneously , can be exchanged for tools from a second tool set at all shooting stations. The device alternative to the teaching claimed here is designed in such a way that each core shooting machine is assigned at least one parking station for the transfer part with the cores located thereon and that the parking station for receiving a tool that can be removed from the transfer path when the tool is changed for the first time and returned to the tool when it is changed again Transfer path insertable transfer part is used so that there are only transfer parts carrying cores or core packages made with the tool set in use and in the parking stations only transfer parts carrying cores or core packages made with the tool set not in use. According to this alternative embodiment, it has already been recognized that, in the case of two tool sets used on each core shooter, it is not expedient, particularly from the point of view of the production costs, to "match" both tool sets exactly or to coordinate them with one another in such a way that there are virtually no manufacturing tolerances between them the cores produced with different tool sets at the respective shooting stations. Rather, it makes a lot more sense after a tool change to continue the production with cores that have already been manufactured with the changed tool set.

For this purpose, a parking station for the transfer part is assigned to each core shooter in the alternative device, so that during a first tool change - change to the second tool set - the cores or core packages located at the respective shooting stations - instead of being disposed of - are brought into the parking station . Only when the tool is changed for the first time is the production line restarted in the empty state. If, on the other hand, a previously replaced and cleaned tool set is replaced again, the cores or transfer parts with the cores located on the production line are then brought into the parking station and the parked cores, with the cleaned and now replaceable tool set, are previously manufactured can be slid back into the transfer path at appropriate points. As a result, the transfer path contains only transfer parts carrying cores or core packages made with the tool set in use and transfer parts made with core or core packages carrying the tool set not in use are located in the parking stations. Due to the trick of replacing the cores or core packages manufactured with the corresponding tool set, it is not necessary to restart the production line after changing the tool set. Rather, with the tool set being replaced again, production can be continued exactly where it was interrupted for the purpose of changing. Consequently, with the alternative device, the production is only interrupted until the tool set on the one hand and the transfer parts on the other hand have been changed.

However, the alternative device discussed above is also problematic in practice, since the provision of the parking stations is structurally complex on the one hand and on the other hand requires considerable space.

The present invention is therefore based on the object of specifying a device of the type mentioned at the outset and a corresponding method, according to which reject cores caused by the tool change and start-up times for "filling" the production line with the simplest construction and minimum space requirement are effectively avoided.

The device according to the invention achieves the above object by the features of claim 1. Thereafter, the device according to the invention is designed such that the tools in use of a first tool set can be exchanged for tools of a second tool set on the first core shooting machine, namely after the transfer part with the the first core has left the first core shooting station, that the tools in use in the first tool set can be exchanged for tools of the second tool set on the second core shooting machine after the transfer part with the first and second core has left the second core shooting station, etc., to change of the last tool set at the last core shooting station, so that only the core made with the same tool set can be deposited on a transfer part.

According to the invention, it has been recognized here that the problem of exchanging tool sets can be solved without provision of parking stations for transfer parts to be discharged with cores located thereon, namely in that the tools in use at the various core shooting stations are not exchanged at the same time but at different times. Consequently, in the manner according to the invention, a transfer part carrying a first core is run through all the shooting stations and completed to form a core package. After passing through the respective core shooting station, the respective tool or the respective tool set is then exchanged, so that the subsequent transfer part only carries cores which have already been produced with the replaced tool set. A transfer of transfer parts with cores located on them is therefore superfluous, so that no special parking stations for the transfer parts with the cores located thereon are required. Rather, a transfer part covered with a first core is occupied or completed at each core shooting station with further cores that are manufactured with tools from the same tool set. In each core shooting station, the tool of the tool set to be changed is only exchanged for a tool of the other tool set when the core required for the packaging has been produced and stacked on the transfer part or the other cores. In any case, it is essential here that neither the transfer of transfer parts nor the provision of so-called parking stations is required.

In an advantageous embodiment, the transfer path extending linearly through the shooting stations is formed by the rollers carrying the transfer parts. The rollers can reach under the transfer parts or corresponding overhangs of the transfer parts from the side. With regard to detailed structural designs, reference is expressly made here to patent application P 43 18 259.3-24, the disclosure content of which is expressly claimed here.

With regard to a specific core shooting range, eight core shooting machines or shooting stations with assigned tool sets and transfer parts could be provided, for example.

The method according to the invention achieves the above object by the features of claim 5. This is a method for producing ready-to-cast masks or core packages, a first core being shot at a first core shooting station and on the transfer part serving as the lower tool part of the first core shooting machine spent at the next shooting station, a second core shot at a second core shooting station, the lower tool part of the second shooting station lowered, the transfer part with the first core placed under the upper tool part of the second shooting station and the second core placed on the first core located on the transfer part, etc. The following further method steps are provided according to the invention:

The tools in use of a first tool set are exchanged for tools of a second tool set on the first core shooting machine after the transfer part with the first core has left the first core shooting station. The tools in use in the first tool set are then exchanged for tools in the second tool set on the second core shooting machine after the transfer part with the first and second core has left the second core shooting station. This process is repeated in accordance with the total number of core shooting stations provided, namely until the last tool set at the last core shooting station is changed, so that only cores which are produced with tools of the same tool set are placed on a transfer part.

• die einzige Figur in einem Blockdiagramm, schematisch, eine erfindungsgemäße Vorrichtung mit insgesamt acht Kernschießmaschinen bzw. Kernschießstationen und zwei kompletten Werkzeugsätzen.

There are now various possibilities for advantageously designing and developing the teaching of the present invention. This is on the one hand on the claims and on the other hand to refer to the following brief explanation of an embodiment of the invention with reference to the drawing. In connection with the explanation of the preferred exemplary embodiment of the invention with reference to the drawing, generally preferred configurations and developments of the teaching are also explained. In the drawing shows

• the only figure in a block diagram, schematically, a device according to the invention with a total of eight core shooting machines or core shooting stations and two complete tool sets.

The single figure shows a linearly arranged core shooting system with a total of eight core shooting machines 1 or shooting stations, the core shooting machines 1 having two tool sets 4, each consisting of an upper tool part 2 and a lower tool part 3, and at least slightly different, and identical transfer parts 5 on the one hand as a lower tool part 2 of the first core shooting machine 1 and on the other hand serve as for transporting the core 6 or core package on a transfer path 7 through the device.

According to the invention, the tools 2, 3 in use of a first tool set 4a are exchanged here for tools 2, 3 of a second tool set 4b on the first core shooting machine 1, specifically after the transfer part 5 with the first core 6 has left the first core shooting station. The tools 2, 3 of the first tool set 4a in use are then exchanged for tools 2, 3 of the second tool set 4b on the second core shooting machine 1, specifically also after the transfer part 5 with the first and second core 6 leaves the second core shooting station Has. This process is repeated up to the last core shooting station, namely until the tools 2, 3 of the tool set 4 to be exchanged are changed at the last core shooting station, so that cores 6 manufactured exclusively with the same tool set 4 can be deposited on a transfer part 5.

With regard to the implementation of the method according to the invention, reference is made to the general part of the description in order to avoid repetitions.

In conclusion, it should be emphasized that the above-mentioned exemplary embodiment merely explains the teaching according to the invention, but does not restrict it to the exemplary embodiment.

Claims (5)

1. Apparatus for producing ready-to-use casting shells or core assemblies having at least two linearly arranged core blasters (1) or blasting stations, the core blasters (1) comprising two at least slightly differing tool sets (4a, 4b), each consisting of a tool top part (2) and a tool bottom part (3), and identical transfer parts (5) serving firstly as the tool bottom part (2) of the first core blaster (1) and secondly for transport of the core (6) or core assembly on a transfer path (7) through the apparatus, characterised in that the tools (2, 3) of a first tool set (4a) being used are exchangeable for tools (2, 3) of a second tool set (4b) at the first core blaster (1), namely, after the transfer element (5) with the first core (6) has left the first core blasting station, that the tools (2, 3) of the first tool set (4a) being used are exchangeable for tools (2, 3) of the second tool set (4b) at the second core blaster (1) after the transfer element (5) with the first and second core (6) has left the second core blasting station, and so on, until change-over of the tools (2, 3) of the tool set (4) to be exchanged at the last core blasting station, so that exclusively cores (6) manufactured with the same tool set (4) are arranged to be set down on a transfer element (5).
2. An apparatus according to claim 1, characterised in that the transfer path (7) extending linearly through the blasting stations (1) is formed by rollers carrying the transfer elements (5).
3. An apparatus according to claim 1 or 2, characterised in that the rollers engage laterally beneath the transfer elements (5) or suitable projections of the transfer elements (5).
4. An apparatus according to one of claims 1 to 3, characterised in that altogether eight core blasters (1) or blasting stations with associated tool sets (4a, 4b) and transfer elements (5) are provided.
5. Method for producing ready-to-use casting shells or core assemblies, in which method a first core (6) is shot at a first core blasting station and is brought on the transfer element (5) serving as the tool bottom part (2) of the first core blaster (1) to the next blasting station, a second core (6) is blasted at a second core blasting station, the tool bottom part (3) of the second blasting station is lowered, the transfer element (5) with the first core (6) is brought beneath the tool top part (2) of the second blasting station and the second core (6) is set down on the first core (6) located on the transfer element (5), and so on, in particular using an apparatus according to one of claims 1 to 4,
   characterized by the following further method steps:

   exchange of the tools (2, 3) of a first tool set (4a) being used for tools (2, 3) of a second tool set (4b) at the first core blaster (1) after the transfer element (5) with the first core (6) has left the first core blasting station;

   exchange of the tools (2, 3) of the first tool set (4a) being used for tools (2, 3) of the second tool set (4b) at the second core blaster (1), after the transfer element (5) with the first and second core (6) has left the second core blasting station, and so on, until exchange of the tools (2, 3) of the tool set (4) to be exchanged at the last core blasting station, so that exclusively cores (6) that have been manufactured with tools (2, 3) of the same tool set (4) are set down on a transfer element (5).

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