JP7247198B2 - Method, casting mold and apparatus for manufacturing vehicle wheels - Google Patents

Description

The present invention relates to a method of manufacturing a vehicle wheel from a light metal material, the light metal material being introduced in liquid form into the mold cavity of a casting mold. Furthermore, the present invention provides a casting mold for producing a vehicle wheel from a light metal material, the casting mold having a plurality of mold sections forming a mold cavity for receiving the liquid light metal material. It relates to a mold and an apparatus for manufacturing vehicle wheels.

The basis for driving safety and driving comfort in light metal wheels for passenger cars is the unsprung mass, the decisive factor being the lowest possible weight of the wheel. Due to the mass inertia and rotational torque, the goal is to use lightweight wheels. For this reason, on the one hand, attempts are being made to realize lightweight wheel designs. On the other hand, efforts are being made to reduce weight through material selection. The current state of the art is aluminum or magnesium alloy cast or forged wheels, of which a very high proportion are manufactured using low pressure chill casting or permanent mold casting processes.

In addition to these driving dynamic requirements, aerodynamics or crash related wheel design plays an increasingly important role. Since the aerodynamic properties of wheels are directly reflected in fuel consumption and _CO2 emissions, there is also an increasing need for measures based on legislation. As these requirements are made more stringent by multiple homologation requirements in general approval procedures for passenger vehicles, in particular the Worldwide harmonized Light Vehicles Test Procedure (WLTP) and the Whole Vehicle Type Approval (WVTA), the approval procedure (WVTA) The basic equipment of the complete vehicle in , no longer describes the vehicle, but all equipment variations. Such changes in type testing by the World Standardized Light Vehicle Test Procedures (WLTP) require a rethinking of the design of vehicle components from the point of view of aerodynamics and lightweight construction. In addition, these lightweight construction and aerodynamic requirements are supported by the increasing prevalence of electric mobility under the principle of "light-weight construction increases range". there is Different wheel sizes are used depending on the vehicle type, but these are worse aerodynamically and cause higher blocking in frontal and offset crashes. This worsens the classification results for the entire passenger car range.

These increasing demands of lightweight construction, aerodynamics and crashes require changes in the way vehicle wheels are manufactured. The reason is that standard casting methods such as low pressure chill casting cannot optimally meet these requirements from a process engineering point of view.

In the cold chamber casting process using conventional cold chamber casting systems for manufacturing cast parts, these systems consist of three machine plates: a machine shield, a movable clamping plate and a fixed clamping plate. The clamping unit consists of four columns along which a movable clamping plate can be advanced and retracted, and a movable type usually via a hydraulically driven toggle lever or double toggle lever. The mold clamping force is increased by creating a lock mechanism with a drive unit for driving the clamping plate. A casting mold is formed by providing a movable mold half on a movable mold clamping plate and providing a fixed mold half on a fixed mold clamping plate. The necessary locking force is applied by clamping the column between the machine shield and the stationary clamping plate by the clamping unit.

In conventional cold chamber casting systems, a stationary clamping plate is axially connected to the casting unit. The melt is then passed by the casting unit through the casting chamber through the stationary clamping plate of the casting mold and the stationary mold halves into the mold cavity formed by the casting mold, It is supplied in a direction perpendicular to the dividing plane of the casting mold, ie perpendicular to the dividing plane of the two mold halves. For this purpose, the casting unit comprises a casting plunger, usually hydraulically driven, which is movable in the casting chamber.

The ejector unit is integrated into the clamping unit behind the movable clamping plate. The ejector unit is also typically hydraulically driven to advance and retract the ejector pin within the casting mold. After the casting mold is opened, the ejector pin penetrates the movable clamping plate in order to scrape the casting part from the movable mold half of the casting mold. In addition, a core extraction device is usually provided. The core extraction device on the machine side consists, for example, of hydraulic cylinders. These cylinders are usually mounted on movable clamping plates, but may also be mounted on stationary clamping plates.

As is well known, the casting process in cold chamber casting installations is divided into four successive stages: a pouring stage, a prefilling stage, a mold filling stage and a post-pressurizing stage.

Injection or dosing takes place mechanically, for example with a spoon, or, as in the so-called Vacural method, via channels or via risers with compressed gas from a holding furnace. The injection time is generally between 3s and 15s, depending on the type and amount of injection. If the pouring time is relatively long, there is a risk that part of the melt will already solidify in the casting chamber. Depending on the machine design, the plunger speed in the prefilling stage can generally be adjusted between 0.2 m/s and 0.6 m/s, so that on the one hand the melt is transported as fast as possible and on the other hand air entrainment is avoided as much as possible. This can be done, for example, by breaking up the wave of melt that collects in front of the plunger, by the formation of a spray and/or by reflections in the casting residue area.

During the pre-filling stage, the casting chamber is filled with melt and the plunger transports the melt close to the weir.

To avoid cold flow points, the mold filling stage should be as short as possible. Its duration is typically between 5 ms and 60 ms. During the mold filling stage, the plunger moves the melt at high speed. This speed is generally adjustable over a range of up to 10 m/s or more. At the end of the mold-filling stage, there is a risk of mold rupture due to the high pressure generated by converting kinetic energy into pressure pulses. Modern casting machines therefore have means to absorb the kinetic energy near the end of the filling stage.

In the post-pressurization or hold-pressure stage of the cold chamber casting machine, a holding pressure of 300 bar to 1500 bar, possibly more, is usually set by means of a multiplier. The melt solidifies under this holding pressure and air trapped during mold filling is compressed under the static holding pressure. The percentage of air trapped in the volume void under this holding pressure is low. Volume voids usually consist of blowholes. The cause is insufficient replenishment of the shrinkage-related portion of the melt during the transition from liquid to solid.

In conventional cold chamber casting systems, each weir is generally thin relative to the wall thickness of the cast part. This is because the melt is still liquid in some areas of the cast part, while it has already partially or completely solidified in the weir areas, so that further feeding is not possible or at least difficult. It means something. The formation of a solidified rim shell in the casting chamber after pouring or dosing results in a portion of the melt not only filling the casting mold, but also in shrinkage-related areas within the mold cavity. The supply is also the fact that it is unavailable. A high holding pressure is required to force the residual melt out of the casting residue area for replenishment.

High pressures at the end of the mold filling stage and in the holding stage require high holding forces of the casting mold. This holding force must be applied via the clamping unit of the casting machine.

High casting forces cause elastic deformation of the casting mold and possibly also a bulge around the mold cavity. This ridge can cause burrs to form around the cast part at the parting surfaces and in the area of the slides and slide guides.

High pressure requires a relatively large thickness of the stationary clamping plate and thus a correspondingly long casting chamber. This limits the filling level in the casting chamber to typically 15% up to about 70%, resulting in a correspondingly large air volume in the casting chamber. The traditional orientation of the casting unit with respect to the clamping unit requires relatively long flow paths for the melt within the casting chamber and within the casting system, and often requires cranking to crank the casting system or anvil. Kropfen (where o is an o-umlaut with an umlaut symbol)). Since the application of high pressure can cause solidified casting residue and elastic deformation of the casting chamber in the casting residue area and thus clogging of the casting residue in the casting chamber, under certain circumstances the casting residue is A high opening force is required to pull it away from the casting chamber. This can cause excessive and/or premature wear of the casting chamber and plunger. In addition, clogging of casting residue in the casting chamber often leads to excessive application of piston lubricant. This can result in inclusions within the cast part.

In the case of horizontally arranged casting chambers, this heat load is due to the fact that the lower regions of the casting chambers are heated more during the filling of the hot melt than the upper regions. It causes deformation and causes friction between the casting chamber and the casting piston. The casting piston must follow the course of the casting chamber during the pre-filling and mold-filling stages. The conventional orientation of the casting chamber relative to the casting mold or barrel in which the casting piston moves causes vertical deflection of the melt at the parting plane as it transitions from the casting chamber to the mold or barrel. This is a problem from a flow dynamics point of view and also from a thermal point of view. Deflection of the melt results in turbulence during filling of the mold, increased energy requirements in the casting drive and the risk of significant air entrainment and erosion in the area of the casting set and casting mold. be.

The system-related drawbacks of such conventional cold chamber casting systems are that they compromise casting results and require highly stable and costly machine designs. Additionally, due to the overall design of conventional casting machines, closing the casting mold is a time consuming and costly process.

It is therefore an object of the present invention to provide a method and method for manufacturing vehicle wheels from light metal materials that are able to meet these ever-increasing requirements in terms of lightweight construction, aerodynamics and crash behavior of vehicle wheels. It is to create a mold for casting.

According to the invention, this object is achieved by the features stated in claim 1 .

Besides the low machine and tool requirements, the method according to the invention offers the best prerequisites for meeting the above-mentioned increasing demands with the methods and systems known from the prior art. Pressurized casting as an alternative to traditional low pressure chill casting for vehicle wheels with limited possibilities or traditional cold chamber casting for other cast parts with current process related drawbacks. The use allows various optimizations of lightweight structures, aerodynamic and crash optimizations, and system-related mold design as well as lightweight structure and process optimizations.

Therefore, a change in the process from low-pressure chill casting to pressure casting, whose possibilities are limited in terms of casting cross-section, quality of casting results due to high tool temperatures above 500° C., is made possible by: Various optimizations related to lightweight structure, aerodynamics and crash behavior, as well as system-related geometry design as lightweight structure and process optimization.

The temperature control of the casting mold according to the invention results in very fast and complete filling of the mold cavity, thus avoiding segregation of the liquid light metal material. The solution according to the invention enables a desired temperature level in the mold cavity, so that non-uniform heating of the casting mold and the associated deformation of the casting chamber are avoided and thus melting in specific zones. Premature solidification of light metal materials is prevented. This reduces the piston force as well as increasing the service life of the piston and casting mold.

Due to the use of pressure casting and the thermoregulation of different zones of the casting mold to different temperatures, the forces generated during the casting process are very low, resulting in low casting of vehicle wheels. turbulent or turbulent-free. The manufacture of light metal wheels takes advantage of the cold chamber casting process, but avoids the problems that would otherwise arise from this casting process.

Furthermore, the method according to the invention enables very thin wall thicknesses of up to 1 mm and possibly even less in certain areas of the vehicle wheel. The ability to reduce the wall thickness makes it possible to design vehicle wheels that have significantly better properties with respect to crash behavior than known vehicle wheels. In particular, a vehicle wheel manufactured by the method according to the invention can be optimized for the desired crash behavior.

Because of this low wall thickness, the visible side of the vehicle wheel can be designed to be almost completely enclosed without significantly increasing the weight of the vehicle wheel. This can significantly improve the aerodynamic characteristics of the vehicle wheel. Of course, a plurality of openings for ventilation of vehicle brakes, for example, can also be incorporated on such a visible side. In such a disk-like design on the visible side, structures can be arranged that increase the strength of the vehicle wheel. This means that it is also possible to realize significant improvements in the aerodynamics of vehicle wheels produced using the method according to the invention compared to known solutions.

A further advantage provided by the use of this method is the small draft angle of less than 1 degree maximum. This opens up unprecedented stylistic design possibilities for vehicle wheels. Furthermore, very fine surfaces can be made with very small radii of 1 mm or less.

The fact that the vehicle wheel can be finished in one casting reduces the machining required after casting by about 80% or more. Less post-processing required means less waste is generated, which helps protect the environment. The method according to the invention significantly reduces casting time and allows substantially flash-free casting, while also reducing raw materials and energy requirements. Moreover, rapid casting and solidification by means of the casting surface (Gusshout) means that the otherwise necessary artificial age hardening (Warmauslagerung komplett) can be completely or partially eliminated. A vehicle wheel manufactured by the method according to the invention has low distortion. It also allows the fine gradation required for glossy turning.

The lightweight construction achievable by the method according to the invention increases the cruising range of motor vehicles equipped with such vehicle wheels. This contributes to reducing the load on the environment.

In a very advantageous further development of the invention, the casting mold is thermostatted to a higher temperature in the areas of the vehicle wheel with a smaller cross-section and to a lower temperature in the areas of the vehicle wheel with a larger cross-section. In some cases, the melt is maintained in a liquid state for a sufficiently long period of time to prevent premature solidification of the melt in relatively narrow areas of the mold cavity, and in relatively wide areas of the mold cavity. ensures that clotting is initiated in a timely manner. Overall, this results in uniform solidification of the entire cast vehicle wheel.

Injection velocities of the molten light metal material into the mold cavity of more than 5 m/s have proven to be particularly advantageous with respect to the rapid filling of the mold cavity and the concomitant uniform solidification of the liquid light metal material. is the case.

It can also be provided that the vent zone in which the casting mold is vented is thermostatted to a temperature substantially lower than the other zones of the casting mold. This ensures rapid solidification of the melt in the aeration zone, thus preventing the melt from leaking out of the casting mold. In addition, this allows for targeted solidification while allowing the liquid light metal material to aerate, even at high casting speeds, and in a compact design.

A casting mold for manufacturing a vehicle wheel according to the invention is specified in claim 5 .

The casting mold according to the invention allows very simple adjustment of different temperature ranges in the casting mold through the use of a temperature control device, so that the production of cast vehicle wheels can be facilitated at any time. can also be performed under optimum conditions. The casting mold according to the invention can have a relatively simple design and is always maintained at a set temperature by means of temperature control devices.

It is particularly advantageous for setting the desired temperature at the transition into the mold cavity of the casting mold if the temperature control device is designed as a pressurized water circuit, an electric heating cartridge and/or a pressurized oil circuit. be.

Heat outflow and/or heat inflow can be relatively easily controlled if the mold sections and/or the inserts and/or ventilation elements connected to these mold sections are made of different materials. .

Further, a temperature regulation device may be operatively connected to the control device for controlling and/or regulating the temperature of the temperature regulation zone. This makes it very easy to control or regulate the temperature in individual zones of the mold cavity or casting mold.

A further embodiment which is advantageous with respect to the simple construction or design of the casting mold according to the invention can be the fact that at least two mold parts are provided which are movable with respect to each other.

Another advantageous embodiment of the invention resides in the fact that at least one of the mold parts has a plurality of adjustment elements for adjusting the mold parts to different temperatures to function in casting molds. could be. These adjusting elements are suitable for compensating for tolerances between individual components of the casting mold, so that at least one of the mold parts, and thus the casting mold, The entire mold can be coordinated very well with respect to the alignment of the individual components. This significantly reduces costs as the casting mold can be used at temperatures other than its design temperature. Each adjustment element can also be made of a different material to compensate for size differences of each component involved, depending on the production of the molded part and the heat input to the molded part. In addition to compensating for size differences, these adjustment elements can also target heat insulation or heat transfer, so that in addition to the production of the molded part and the heat input to the molded part, is the size difference compensated and thermally insulated? , or heat is transferred. In addition to size compensation, these adjustment elements are also capable of absorbing and/or damping introduced shocks and/or forces.

In order to prevent melt leakage due to the venting of the casting mold, the venting area of the mold cavity of the casting mold is provided with surface variations in the form of a temperature-controlled labyrinthine structure and/or in cross-section. At least one change and/or at least one deflection may also be provided.

A device for manufacturing a vehicle wheel with such a casting mold is claimed in claim 12 .

The apparatus, which may for example be in the form of a casting machine, can be used particularly advantageously for carrying out the method according to the invention.

In order to achieve easy and safe opening and closing of the casting mold, at least one guide element which does not belong to the casting mold is used to move at least the mold part of the casting mold. One may be movable relative to another mold part in the direction of closing the casting mold. As a result, it is also possible to dispense with the construction of additional guide elements in the casting mold and to move the mold part of the casting mold without such guide elements. By locating the guide elements in the device and not specifically in the casting mold, a considerable cost reduction is achieved as these guide elements can be used for most different casting molds. can be done. In addition, this allows rapid casting mold changes, ie rapid replacement of individual mold parts of the casting mold.

Another advantageous embodiment of the invention may be that each mold section is thermally isolated from the guide elements that move that mold section. As a result, excessive heating of the guide element is prevented, so that the guide element can be prevented from warping, the accuracy of movement in each component of the device is increased, and disturbance is avoided.

Another advantageous embodiment of the device can make at least two of the mold parts movable in a direction perpendicular to the closing direction by means of respective gripping elements. This allows a very fast opening and closing of the casting mold, so that the productivity of the device according to the invention can be significantly increased.

A simple and fast connection of the mold parts with guide elements and/or gripping elements is provided by connecting at least one of the mold parts to at least one guide element and/or each gripping element by means of a fast connection means. If you can connect to an element.

In order to enable efficient supply and/or actuation of the temperature control devices, it is also possible for the respective units for supplying the temperature control devices to be integrated in the apparatus.

Another advantageous embodiment of the invention may be that at least one vacuum unit is provided for extracting air from the mold cavity. This vacuum unit allows a fast and easy suction of air from the mold cavity in order to fill the mold cavity with liquid light metal material.

In the following, a number of examples of embodiments of the invention are shown in principle with reference to the drawings.

1 is a side view of a device according to the invention in a first state; FIG. 2 is a view according to arrow II in FIG. 1; FIG. 2 is a perspective view of the device of FIG. 1; FIG. Figure 2 is a side view of the device of Figure 1 in a second state; Figure 5 is a perspective view of the device of Figure 4; Figure 2 is a side view of the device of Figure 1 in a third state; Figure 7 is a perspective view of the device of Figure 6; Figure 2 is a side view of the device of Figure 1 in a fourth state; Figure 9 is a perspective view of the device of Figure 8; 1 is a casting mold according to the invention; Fig. 3 is a further view of part of the casting mold according to the invention; FIG. 4 is another view of part of a casting mold according to the invention;

1 to 9 show various views of an apparatus 1 for producing the vehicle wheel 2 shown in FIGS. 6 to 9 by pressure casting. The vehicle wheel 2 can basically be of any size and shape. Accordingly, the vehicle wheel 2 shown in FIGS. 6-9 shall be considered as exemplary only. A light metal material, preferably an aluminum or magnesium material, is used for the pressure casting of the vehicle wheel 2 . For this purpose, light metal materials known per se can be used for the manufacture of the vehicle wheel 2 which are suitable for the method described below.

The device 1 has a casting mold 3 . The casting mold 3 is in the closed position in the representations of FIGS. The casting mold 3 here has four mold parts. That is: fixed mold half 4 or stationary mold half, movable mold half 5 , upper gate or upper slide 6 , lower gate or lower slide 7 . These mold parts of the casting mold 3 can be accommodated with or without a zero point clamping system and can have very smooth, high quality surfaces. This surface provides a very high surface quality of the vehicle wheel 2 which does not need to be treated with coatings or the like, or only to a very limited extent. Of course, the casting mold 3 can have more than the four mold sections described and illustrated herein. The movable mold parts, i.e. the movable mold half 5, the upper slide 6 and the lower slide 7, are moved from the states shown in FIGS. 1, 2 and 3 to FIGS. It can be moved into the states according to FIGS. 5, 6 and 7 and FIGS. All these guide elements described below are part of the device 1 and do not belong to the casting mold 3 .

extending horizontally in order to guide the movement of the movable mold half 5 in the closing direction of the casting mold 3, indicated by the arrow "x" in FIG. A plurality of guide columns 8 are used. These are attached on the one hand to the movable clamping plate 9 and on the other hand to the rear machine shield 10 forming a counter bearing. By moving the movable clamping plate 9, which is also the guiding element of the casting mold 3, against the closing direction x, the movable mold half 5 is moved from its position shown in FIG. is moved to the position shown in When the movable mold half 5 is moved with respect to the fixed mold half 4 in this way, the upper slide 6 and the lower slide 7 are also moved with respect to the fixed mold half 4 in the direction opposite to the mold closing direction x. be moved. For driving the movable clamping plate 9, a drive device known per se, not shown here, can be used. The movable clamping plate 9 here is movably mounted on the rail 11 of the device 1 . The guide column 8 forms a guide for the movable clamping plate 9 and absorbs horizontal clamping forces during casting. The stationary mold half 4 is attached to the stationary mold clamping plate 12 . The fixed clamping plate 12 is connected to the casting unit 13 . The casting unit 13 is responsible for introducing the liquid light metal material into the mold cavity 14 formed between the mold parts of the casting mold 3 . The casting mold 3 is provided in a manner known per se with the negative form of the vehicle wheel 2 to be produced. The filling of the mold cavity 14 with the liquid light metal material takes place in particular from the outer periphery of the mold cavity 14 . The casting mold 3 is preferably designed in such a way that injection of the material is avoided during the introduction of the liquid light metal material into the mold cavity 14 . The introduction of the liquid light metal material into the mold cavity 14 takes place at relatively low pressures, up to 100 bar or slightly more.

During the actual casting process, the movable clamping plate 9 and the stationary clamping plate 12 on which the movable clamping plate 9 is supported also generate a clamping force. For this purpose, the drive elements or devices used to move the movable clamping plate 9 can have, for example, hydraulic cylinders and/or toggle lever elements or closing elements. The clamping of the casting mold 3 can be effected in a form-fitting and/or frictional connection by means of manual, semi-automatic or fully automatic clamping elements. The stationary clamping plate 12 can have a mold injection device and/or an integrated pressure medium system, not shown.

The upper slide 6 is movable from its position shown in FIG. 1 or 4 to the position shown in FIG. In the position shown in FIG. 6 the upper slide 6 has been moved vertically upwards with respect to the movable mold half 5 by the upper gripping element 15 . Similarly, the lower slide 7 is also moved downwards by the lower gripping elements 16 from its position shown in FIGS. 1 and 4 relative to the movable mold half 5 to its position shown in FIG. be able to. The gripping elements 15 and 16 and the movable clamping plate 9 can be operated manually, semi-automatically or fully automatically. The two gripping elements 15 and 16 are also guide elements for the casting mold 3 . Both guide elements for moving the mold parts of the casting mold 3 can also be provided with a pressure medium in a manner not shown.

Here the upper slide 6 and the lower slide 7 are displaced vertically, whereas the vertical separation of the casting mold 3 in the area of the two slides 6 and 7 thus separates the two slides. A horizontal movement would also be possible. In this case the two gripping elements 15 and 16 would be left and right gripping elements. In any case, the two slides 6 and 7 are preferably moved by the respective gripping elements 15 and 16 in a direction perpendicular to the closing direction x.

In the method of manufacturing the vehicle wheel 2 thus carried out by the apparatus 1 and the casting mold 3 , the light metal material is in liquid form in the mold cavity 14 of the casting mold 3 by the casting unit 13 . injected. This injection of liquid light metal material takes place at a high speed of more than 5 m/s. This high injection speed is achieved by a corresponding movement of the piston of the casting unit 13, not shown. The vehicle wheel 2 is manufactured by pressure casting. Thus, the casting mold 3 is thermostated to different temperatures in different areas. This different temperature adjustment of the casting mold 3 is explained in more detail below by way of example. The casting mold 3 is preferably thermostatted to a high temperature in areas where the vehicle wheel 2 has a small cross section and to a low temperature in areas where the vehicle wheel 2 has a large cross section. Although the vehicle wheel 2 has very different cross-sections, temperature control of the casting mold 3 makes it possible to control or adjust the solidification behavior of the liquid light metal material. In addition, the ventilated area of the casting mold 3 is thermostated to a significantly lower temperature than the other areas of the casting mold 3 . This area in which the casting mold 3 is vented will be explained in more detail below.

Each mold part (molding part) of the casting mold 3, i.e. the stationary mold half 4, the movable mold half 5, the upper slide 6 and the lower slide 7, can be entirely or partially made of different materials. configurable. In particular, the material of the individual mold parts can be selected according to the temperature to be set when the casting mold 3 is thermostatted.

After solidification of the liquid light metal material, the mold parts are separated as described above in order to open the casting mold 3 . The casting (casting) part produced by the method, ie the vehicle wheel 2 is ejected by an ejection unit 17 . The ejector unit 17, like the guide column 8, is attached to the movable clamping plate 9 on the one hand and to the rear machine shield 10 on the other hand. The ejection unit 17 here comprises a hydraulic unit 18 . A hydraulic unit 18 moves the ejection unit 17 in a manner known per se. After ejection of the vehicle wheel 2 from the casting mold 3, the casting mold 3 is reversed to introduce the liquid light metal material into the mold cavity 14 to produce the next vehicle wheel 2. That is, it can be moved from the state shown in FIGS. 8 and 9 to the state shown in FIGS. 1, 2 and 3 through the states shown in FIGS. 6 and 7 and the states shown in FIGS.

It goes without saying that, after completion, the illustrated vehicle wheel 2 can be connected to a tire not shown in the drawing and filled with air or gas. It is also possible to construct the vehicle wheel 2 from several individual parts. These discrete parts can also be manufactured using the methods described herein.

Figures 10, 11 and 12 show an exemplary embodiment of a casting mold 3 in which a stationary mold half 4, a movable mold half 5, an upper slide 6 and a lower slide 7 are It is shown. An upper gripping element 15 and a lower gripping element 16 are also visible in these figures. Figure 10 also shows that the upper slide 6 and the lower slide 7 are connected to the upper gripping element 15 and the lower gripping element 16 by means of quick connections 19 and 20 respectively. Guide elements belonging to the device 1 are provided by means of fast connections 19 and 20 in order to enable fast opening and closing of the casting mold 3 by moving the mold parts relative to each other as described above. can be quickly connected to the mold part belonging to the casting mold 3 .

In addition, FIG. 10 shows that the upper slide 6, the lower slide 7 and the movable mold half 5 are thermally separated from the corresponding guide elements, namely the upper gripping element 15, the lower gripping element 16 and the movable clamping plate 9. is separated into A corresponding insulating element 21 is provided for this purpose. Due to the cutting direction of this cross-sectional view, not all insulating elements 21 are visible. A heat insulating element 21 may also be provided between the stationary mold half 4 and the stationary clamping plate 12 . This thermal decoupling of the mold parts from the guide elements prevents unintentional heating of the guide elements, so that the function of the device 1 with respect to opening and closing of the casting mold 3 even in the event of temperature changes. is guaranteed.

FIG. 10 further shows some temperature control devices. These temperature control devices allow the casting mold 3 to be temperature controlled to different temperatures in order to enable uniform solidification of the light metal material in the mold cavity 14 . These temperature regulating devices are pressurized water circuits, some holes 22 of which are shown in FIG. 10, electric heating cartridges 23 and pressurized oil circuits, some of whose holes 24 are also shown in FIG. is preferred. Other heating or cooling elements can also be used as temperature control devices if desired.

These temperature regulating devices, namely the pressurized water circuit, the electric cartridge heater 23 and/or the pressurized oil circuit, are connected to a control device 25, also shown in FIG. It is possible to control and/or regulate the temperature of The control device 25 can also be operatively connected to a plurality of temperature sensors not shown. These temperature sensors measure the actual temperature in the individual parts of the casting mold 3 and thus enable correct temperature setting. In addition to temperature monitoring of the molded part or of the molding zone, the control device 25 can also monitor other process data and/or geographic data and/or other monitoring information and transmit these to higher systems, such as machine control systems. . In this way, the casting mold 3 can be finely temperature-controlled during production and/or for preheating, so that the different temperatures and coefficients of thermal expansion of these mold parts contribute to the different temperatures involved. All influencing parameters such as different thermal expansions of various components can be monitored and controlled.

The temperature control of the casting mold 3 can of course be designed differently for each individual mold and thus for each individual vehicle wheel 2 produced by the casting mold 3 or the device 1 .

1, 4, 6 and 8 show very schematically a plurality of units 26 used to supply temperature control units for temperature control of the casting mold 3 and incorporated in the apparatus 1. showing. These units 26 here are shown as being built into the rail 11 . However, it is of course possible to arrange or mount these units 26 at other positions within the device 1 .

1, 4, 6 and 8 also show a vacuum unit 27 used to evacuate air from the mold cavity 14. FIG. A vacuum unit 27 for generating a corresponding vacuum is also integrated in the device 1 and is also shown in the rail 11 by way of example only. The connection between the temperature control device and each unit 26 and the connection between the mold cavity 14 and the vacuum unit 27 are not shown in these figures. These connections can be made in a wide variety of well known ways.

FIG. 11 shows a perspective view of part of the casting mold 3 . In FIG. 11 the upper slide 6, the lower slide 7, the movable mold half 5, the control device 25 and part of the mold cavity 14 are visible. Also clearly visible in FIG. 11 are the two gripping elements 15 and 16 and the connection of the gripping elements 15 and 16 to the two slides 6 and 7 . Furthermore, it can be seen from FIG. 11 that at least one of these mold parts, here both the upper slide 6 and the lower slide 7, has several adjustment elements 28. FIG. These adjustment elements 28 allow these mold sections to be aligned or adjusted with respect to each other. The two slides 6 and 7 here are aligned by means of these adjustment elements 28 to the stationary mold half 4, not shown in FIG. This makes it possible to compensate for tolerance deviations that inevitably occur during the manufacture of individual moldings. Furthermore, the adjustment element 28 serves to adjust the mold parts of the casting mold 3 to different temperatures applied to the casting mold 3 . The adjusting element 28, which may also be referred to as an insert part, can be made of a different material than the slide 6 or 7 in which or on which the adjusting element 28 is arranged.

In order to prevent leakage of the liquid light metal material, all mold parts of the casting mold 3 have different thicknesses and, if necessary, adjustable, so that they remain closed even under bursting pressure. These adjustment elements 28 , which can also be designed as cylinders, allow adjustment of the casting mold 3 in the separation areas between the mold parts of the casting mold 3 . This, in addition to the technical and economic requirements that entail in the case of the vehicle wheel 2, together with the technical and economic design of the casting mold 3, makes the Each mold section of the casting mold 3 can be adjusted with a respective temperature zone so that the problems that arise are taken into account in the production of the vehicle wheel 2 . The adjustment element 28 can also be reworked or replaced after suitable tests, thus ensuring a safe and secure sealing of the casting mold 3 .

FIG. 12 shows a view of another mold part of the casting mold 3 , namely the stationary mold half 4 . The stationary mold half 4 has a vent area 29 adjacent the mold cavity 14 . Vent area 29 allows air in mold cavity 14 to escape at the start of the casting process. In order to prevent the escape of liquid light metal material from the vent area 29, in addition to air, the vent area is thermostated to a temperature sufficiently lower than the other areas of the casting mold 3, as described above. . In addition, a temperature-controlled or temperature-regulated labyrinthine structure 30 is provided in the ventilation zone 29 . The labyrinthine structure 30 makes leakage of the liquid light metal material from the mold cavity 14 more difficult. Additionally or alternatively to the labyrinthine structure 30, the ventilation area 29 may have a change in cross-section, surface expansion or surface contraction and/or deflection. The ventilation zone 29 or the ventilation elements forming the ventilation zone 29 can be made of a different material than the other components of the casting mold 3 . A copper material, such as brass or bronze, for example, can be used for the vent area 29 . Of course, vent zones the same as or similar to vent zone 29 can be positioned at other locations in mold cavity 14 .

The ventilation zone 29, which can also be referred to as a ventilation unit, in conjunction with its own thermal management, allows the system to brake the liquid light metal material on its own through the described geometrical design, thus enabling the realization of short ventilation distances. To enable, depending on requirements, the connection of full or reduced cross-section to the vacuum unit 27 can be variably controlled via one or more holes 31 . Optionally, these vent zones 29 can also be provided with vacuum valve connections or used without subsequent vacuum connections in order to allow the casting mold 3 to function fully or partially as an overflow. can also

FIG. 12 further shows closed belts or rings 32 . The ring 32 is formed by offsetting the plane of the stationary mold half 4 . In the closed state of the casting mold 3 , the adjusting element 28 is pressed against the ring 32 in order to ensure the tightness of the casting mold 3 . The ring 32 thus absorbs the forces that occur during casting.

Claims (18)

A method of manufacturing a vehicle wheel (2) from a light metal material, said light metal material being introduced in liquid form into a mold cavity (14) of a casting mold (3),
said vehicle wheel (2) is produced by pressure casting, said casting mold (3) being thermostatted to different temperatures in different zones,
Said casting mold (3) comprises at least a stationary mold half (4), a movable mold half (5), an upper slide (6), a lower slide (7) and a plurality of adjustment elements (28). and
Said plurality of adjustment elements (28) are provided on said upper slide (6) and said lower slide (7), and when said vehicle wheel (2) is manufactured by said pressure casting, said A method characterized by aligning said upper slide (6) and said lower slide (7) with respect to a stationary mold half (4) and adjusting said different zones to different temperatures. The casting mold (3) is thermostatted to a high temperature in areas of small cross-section of the vehicle wheel (2) and to a low temperature in areas of large cross-section of the vehicle wheel (2). 2. The method of claim 1, wherein: 3. A method according to claim 1 or 2, characterized in that the molten light metal material is injected into the mold cavity (14) at a high velocity of more than 5 m/s. 3. A ventilation zone (29) of said casting mold (3) is thermostatted at a temperature substantially lower than the other zones of said casting mold (3). Item 1, 2 or 3, the method. A casting mold (3) for manufacturing a vehicle wheel (2) from a light metal material, comprising a plurality of mold parts forming a mold cavity (14) for receiving said liquid light metal material. , in the casting mold (3),
The casting mold (3) has a plurality of zones temperature-controlled to different temperatures by a temperature control device,
Said casting mold (3) comprises at least a stationary mold half (4), a movable mold half (5), an upper slide (6), a lower slide (7) and a plurality of adjustment elements (28). and
The plurality of adjustment elements (28) are provided on the upper slide (6) and the lower slide (7) and function to adjust the mold sections to different temperatures and the upper slide (6). ) and the function of aligning said lower slide (7) with said stationary mold half (4). 6. Casting mold (3) according to claim 5, characterized in that the temperature control device is formed as a pressurized water circuit, an electrothermal cartridge (23) and/or a pressurized oil circuit. 7. Casting mold (3) according to claim 5 or 6, characterized in that the mold parts and/or the inserts and/or ventilation elements connected to the mold parts each consist of different materials. 8. Claim 5, 6 or 7, characterized in that the temperature regulation device is operatively connected to a control device (25) for controlling and/or regulating the temperature of the temperature regulated zone. casting mold (3). Casting mold (3) according to any one of claims 5 to 8, characterized in that at least two mold parts are provided which are movable with respect to each other. At least one change in surface and/or cross-section in the form of a temperature-controlled labyrinth-like structure (30) in the ventilation zone (29) of the mold cavity (14) of the casting mold (3) and/or at least one deflection is provided. The casting mold according to any one of claims 5 to 10, characterized in that said stationary mold half (4) further comprises a ring (32) against which said plurality of adjustment elements (28) are pressed. type (3). Apparatus (1) for manufacturing vehicle wheels (2) comprising a casting mold (3) according to any one of claims 5-11. Said 13. Device (1) according to claim 12, characterized in that it is movable in the closing direction (x) of the casting mold (3). 14. Apparatus (1) according to claim 12 or 13, characterized in that the mold parts are thermally decoupled from the guide elements that move the mold parts. 15. According to claim 12, 13 or 14, characterized in that at least two of said mold parts are movable in a direction perpendicular to the closing direction (x) by means of respective gripping elements (15, 16). device (1). 4. Claim characterized in that at least one of said mold parts is connectable to at least one guiding element and/or to a gripping element (15, 16) by means of quick connection means (19, 20). 16. Device (1) according to 13, 14 or 15. Apparatus (1) according to any one of claims 12 to 16, characterized in that respective units (26) for supplying said temperature control devices are integrated in said apparatus (1). Apparatus (1) according to any one of claims 12 to 17, characterized in that at least one vacuum unit (27) is provided for extracting air from the mold cavity (14).

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