WO2015155170A1

WO2015155170A1 - Die-casting machine and die-casting process for producing a plurality of castings

Info

Publication number: WO2015155170A1
Application number: PCT/EP2015/057485
Authority: WO
Inventors: Rupert Frech
Original assignee: Bühler AG
Priority date: 2014-04-08
Filing date: 2015-04-07
Publication date: 2015-10-15
Also published as: EP2929957A1

Abstract

The present invention relates to a die-casting machine, comprising a movable mounting plate (3) and a fixed mounting plate (2), a mould half (16) arranged on the movable mounting plate (3) and a mould half (16) arranged on the fixed mounting plate (2), characterized in that the die-casting machine has at least two, preferably two casting drives (17; 18a, 18b) and an analogous number of shot assemblies (19a, 19b) assigned to the casting drives (18a, 18b). The present invention also relates to a process for producing castings in a die-casting process, preferably by way of such a die-casting machine, and also to a casting mould (25, 27) for a die-casting machine and to the use of such a die-casting machine or casting mould (25, 27) to produce castings, preferably castings for the automotive sector or the electronics sector.

Description

Die casting machine and die casting process for the production of several castings

The present invention relates to a die casting machine and a die casting method for more efficient and economical production of die cast components.

Die casting machines are used for the production of metallic castings such as engine blocks. By way of example, WO 2008/131571 A1 describes a horizontal two-plate die-casting machine. This two-plate die casting machine comprises a movable clamping plate (BAP) and a fixed clamping plate (FAP), to each of which a

Mold half is arranged. By moving the movable platen, the die can be opened and closed. In the closed position, the two clamping plates are pressed firmly against one another so that the two mold halves form a closed mold. In a formed by the ge ^¬ connected mold cavity, a molten metal is introduced under pressure and cooled to solidify. The solidified casting can be removed after opening the mold (by moving the movable platen). The movement of the movable platen takes place in the machine according to WO

2008/131571 AI on columns, preferably four columns.

The shape formed by the two mold halves can be configured differently. Are known molds with a single cavity or with multiple cavities. In the latter case, the cavities may have the same dimensions (allowing simultaneous production of components of the same shape), or alternatively, the cavities may have different dimensions (thereby enabling the simultaneous production of components of different shapes). The trend in the automotive industry is to produce castings such as structural components, engine blocks or gearbox housing ever larger ^¬ and thin-walled. However, the size of a component which can be produced in the conventional die casting method has its limits in that during the casting process, the molten metal must be able to flow in cavities in the casting mold and to be able to completely fill them. For this purpose, the molten metal during the casting process but only a short period available. For larger components game, the pressure should be increased examples, with which the metal ^¬ melt is pressed into the mold, as hereinafter be ^¬ but performs a disadvantageous increase of the clamping force to be applied would result. In addition, with the size of the component to be produced, the closing pressure required for holding the mold halves together during the casting cycle increases. By the pressing of the molten metal into the mold where a pressure of the ^¬ sen size among other things, the pressure applied to the melt during the casting cycle pressure and tivity of the dimensions of the catalog (s) is formed dependent. From this pressure results the so-called explosive force which would move the two mold halves apart during the casting cycle, if one did not keep the mold halves closed by applying a closing force exceeding the explosive force. Since the closing force can not be arbitrarily increased, but depends on the size of the die casting machine, the dimensions of the cavity (s) are set in a conventional die casting ^machine .

So far, the premium segments in the automotive sector have been equipped with structural components, making them lighter and stiffer. But the need of the automotive industry is Also equip mass vehicles (eg compact and upper middle class vehicles) with aluminum and magnesium structural components. From the point of view of the lightweight construction strategy, much speaks for such an approach. However, the productivity of conventional die casting machines is currently not designed to cost-effectively produce the variety of lightweight metal components required for this expansion. Typically, 6 assemblies are now installed in pairs in automotive production: shock tower (shock tower) front and rear, front and rear and side member, end wall and instrument panel.

For an economical production of the large number of light metal components required for this approach, it is necessary to produce several such components simultaneously in a mold having a plurality of cavities (multi-cavity mold) in a casting cycle, i. For example, produce four casts of the component in a casting cycle. However, this requires an increase in the amount of mold cavities. The provision of a cavity in duplicate in one mold means that the cavity dimensions are doubled with the disadvantages described above, in particular an increase in the closing force which is required during the casting cycle for holding the mold halves together. With conventional die casting machines, the required expansion of the number of pieces of light metal components can not be achieved, since limits are set by the maximum closing force to be applied.

It was the object of the present invention to provide a die casting machine and a die casting method for the economic production of a plurality of components. The above object is achieved by a die casting machine, comprising a movable platen and a fixed platen, a arranged on the movable Aufspannplat ^¬ te mold half and arranged on the fixed platen mold half, characterized in that the pressure ^¬ casting machine at least two, preferably two Casting drives and an analogous number of Giessgar- nituren assigned to the casting drives has. The present invention is based on the idea that not all Kavi ^¬ activities of a die-casting mold with a single Giessantrieb to fill, but to use at least two Giessantriebe for filling the cavities. One hand this has the advantage that the connection paths Zvi ^¬ rule Giessgarnituren and cavities are reduced because the molten metal no longer has starting to flow from a Giessantrieb in all wells but may be starting channeled by several ^¬ ren different Giessantrieben in different cavities.

In addition, with the aid of the diecasting machine according to the invention it is possible to carry out the production of castings in different cavities during a casting cycle with such a time delay that the entire casting cycle can be carried out with a lower closing force. The Ka ^¬ vitäten can be sequentially filled by different Giessantriebe, so to be compensated explosive force occurs only in the filled cavities and the total explosive power can not be compensated, which would occur at the same time fuel ^¬ len of all existing cavities. This will be explained in detail below. With the aid of the diecasting machine according to the invention, it is thus possible to produce significantly more castings at the same time within one casting cycle, without an increase in the closing force being required for this purpose. As a result, with the die casting apparatus according to the invention, significantly higher productivity, typically 80-100%, at least 40-60% higher productivity, can be achieved than with conventional die casting machines. With conventional die casting machines only so many castings can be produced simultaneously as possible in the context of a ^¬ adjustable maximum closing force. Especially with larger components multiple casting in a casting cycle would be limited because of the strong increasing closing force possible. As a result, several herkömm ^¬ Liche die casting machines would accordingly be operated simultaneously in order to achieve a comparable with the inventive die casting pro ^¬ productivity. This would have a correspondingly much larger footprint, more operators, etc. result. For this reason, the use of die-cast light metal castings in mass-produced vehicles (eg compact and mid-range vehicles) has not been realized so far. By means of the present invention, the use of pressure casting light metal components in mass-produced vehicles will be economically viable for the first time.

According to the invention, a "casting unit" is understood as the entirety of all components of a die-casting machine which are used for the movement of a casting piston and for the pressurization of the molten metal. A casting drive an inventive die casting machine includes a hydraulically operated übli ^¬ cherweise casting cylinder having arranged therein moveable drive piston, a shot valve for controlling the movement of the drive piston in the casting cylinder and an accumulator. In addition to the casting drive, a casting unit comprises further components such as a guide frame, tie rod, hydraulic tank, and a hydraulic control block.

The "casting drive" is connected to the die using a "casting set". A Giessgarnitur consists of a Giess- piston rod, which is coupled at its one end to the drive piston casting cylinder, a casting piston which is coupled to the mold-side end of the casting piston rod, and a casting chamber in which the casting piston can move and filled in the casting chamber Melt through his movement in the

Can press die. The casting chamber is connected to at least one mold cavity in the die casting mold. According to the invention is any Giessantrieb a shot assembly zugeord ^¬ net, that is a respective shot assembly is the link be- see a particular Giessantrieb and the pressure casting mold.

The skilled person is familiar with casting units, casting drives and casting installations. Die casting machines are well known. A distinction is made between the casting assembly between a cold chamber and a hot chamber die casting machine. The casting is casting machine at a hot-chamber pressure held in a crucible with ge ^¬ schmolzenem metal. A casting piston moves into the casting container and forces the molten metal through a likewise at least partially disposed in the crucibles Giess ^¬ container in the mold. Casting containers and casting pistons are permanently exposed to molten metal in this process. The shot assembly of a hot chamber die casting machine is fundamentally ^¬ additionally designed differently than that of a cold-chamber die casting machine. In a cold chamber die casting machine, the metal is melted in a separate apparatus and kept warm in a molten state in a holding furnace. The amount of molten metal required for producing the desired component is introduced into a cold casting chamber via a filling opening and pressed into the casting mold with the aid of a casting piston movably arranged in the casting chamber.

Cold chamber and hot chamber die casting machines are well known to those skilled in the art. According to the present invention, cold chamber die casting machines are preferred.

The present invention may be practiced with horizontal die casting machines or vertical die casting machines. Horizontal die casting machines are preferred according to the invention.

Die casting machines are designed as so-called 3-plate machines or 2-plate machines. In a 3-plate machine, the movable platen is moved on usually four Füh ^¬ approximately columnar means of an additional third plate supported on a toggle lever mechanism relative to the fixed clamping plate. The closing force is also generated via the Kniehebelme ^¬ mechanism. In a two-platen machine, the moving platen is moved on usually four guide columns by means of a motor and lock cylinder. The closing force is transferred to the movable platen with the aid of tensioning cylinders, with which the guide columns can be fixed to the movable platen. According to the present invention, 2-plate die casting machines are preferred. A preferred 2-plate die casting machine is described in WO 2008/131571 AI. The present invention can be carried out both with conventional die casting machines and with vacuum die casting machines or other special designs of die casting machines. The person skilled in the corresponding die casting machines are known. In a conventional die casting machine, the shot assembly is disposed on the fixed platen and connected via a Verbin ^¬ dung channel with the cavity in the plane formed by the two mold halves in the closed condition form. The inventive die casting machine has at least two casting drives. According to a preferred embodiment of the present invention, the die casting machine has exactly two casting drives. If necessary, however, further casting drives may also be present, so that the die-casting machine according to the invention may preferably have from 2 to 10 casting drives. Since, according to the invention, each casting is associated with a casting set, as described above, the die casting machine according to the invention has the same number of casting sets, ie at least two, preferably two to ten and more preferably exactly two casting sets.

The Giessgarnituren the die casting machine according to the invention should preferably be ^¬ such arranged on the fixed platen that the flow paths of the molten metal are kept as short as possible. According to a preferred embodiment, the two or in each case two Giessgarnituren (and accordingly ^¬ the associated Giessantriebe) horizontally nebeneinan ^¬ or vertically stacked or diagonally above each other arranges, preferably symmetrically about the center of the back surface of the fixed platen. More preferably, the two or two sets of plugs each are placed close to (ie spaced typically 10 to 50 cm apart, depending on the size of the plumbing fixtures) about the center of the back surface of the fixed platen. Grund ^¬ addition, the Giessgarnituren but also decentralized on the back surface, preferably within the area between the Säu ^¬ lenmuttern on the back surface, the fixed platen be arranged, for example in the left or right part of the back surface of the fixed platen.

For uniform possible distribution of the load, it is ER- preferred inventively provide an even number of Giessantrieben (and corresponding Giessgarnituren), for example 2, 4, 6, 8 or 10 Giessantriebe, particularly preferably 2 Giessantriebe which in pairs around the center of Rückflä ^¬ surface of the fixed platen are arranged. According to the present invention, the die casting machine preferably comprises a fixed clamping plate, which has recesses and / or fastening devices for the at least two, preferably two, casting drives. Typically, the Giessgarnituren are arranged on the fixed platen, that part of the shot assembly, typically the casting chamber, arranged in a recess in the fixed platen, and there is buildin ^¬ account during die casting machines. The arranged in the fixed platen part of the Giessgarnitur can protrude from the side remote from the casting drive side of the fixed platen and protrude into an opening of the form on the inside of the fixed platen mold half, or with this opening via a connecting channel be connected. It is also possible to assign the casting completely outside the fixed platen on the back to ^¬ and secure. Can be in this case, appropriate connection channels are provided in the fixed platen through which molten metal from the casting chamber into the mold be ^¬ promotes. The Giessgarnituren in this case have an opening which communicate with a corresponding opening of a connecting channel. Depending on the number of existing casting drives or

Giessgarnituren it may be necessary to strengthen the fixed platen or to produce a firmer material. Corresponding measures are known to the person skilled in the art and can be routinely implemented.

The Giessgarnituren can be fed from the same container with molten metal. But it is also possible to provide for each Giessgarnitur a separate storage container for molten metal, from which the corresponding Giess- garnish is charged with molten metal. According to the invention, the molten metal can be produced from all the metals and metal alloys conventionally used in pressure casting. But it can also be used for example salt mixtures for the production of salt cores.

In principle, it is possible to operate the die-casting machine according to the invention by using only one of the existing casting drives, for example of a conventional form. However, the advantage of the present invention is achieved only by the use of several casting drives during a casting cycle. According to the present invention, a plurality of cavities provided in a casting mold are preferably filled with the aid of the at least two, preferably two, casting drives. Molds with multiple cavities are known. A distinction is made between so-called multi-cavity molds (as shown by way of example in FIG. 4 a) in which a particular cavity is present in the mold several times, and so-called combination molds or unit molds (as shown by way of example in FIG. 5 a in which different cavities in FIG With multicavity molds, a particular casting can be made in a single casting cycle in multiple runs

Giesszyklus be made in multiple copies.

In comparison to conventional multi-cavity molds, combination molds or unit molds, casting molds having a larger number of cavities or having larger cavities can be used with the die casting machine according to the invention. The use of such molds is not possible with conventional pressure casting molds due to the significant increase in the explosive force associated with the use of such casting molds and the high closing force to be applied for compensation.

For example, with conventional die casting machines, only multi-cavity molds can be used which enable the simultaneous casting of two shock towers, ie only one mold can be used which provides two corresponding cavities for shock absorber bridges. The inventive die casting molds for example, but can be used, which provide four entspre ^¬ sponding cavities for shock absorber bridges. In order to It is possible to achieve a doubling of the output per casting cycle (four instead of two shock absorber bridges). Similarly, with the die casting machine according to the invention, a doubling of the output of other components per casting cycle can be achieved (for example two side members instead of one conventionally castable side member, two panel holders instead of a conventionally castable panel carrier).

The present invention thus also relates to a mold for a die casting, made up of two mold halves, which together at least one, preferably provides a plurality of cavities, characterized in that the mold comprises Minim ^¬ least two, preferably two openings, through which the mold filled with molten metal is.

A casting mold according to the invention comprises, like conventional casting molds, two mold halves which can each be arranged on a movable and a fixed clamping plate of a die casting machine. Each mold half comprises on its inside, ie the side which is not attached to the movable or fixed platen, one or more recesses, wel ^¬ che in the state of joining the two mold halves form the mold cavity (s). Each mold half also comprises on its inside one or more recesses which form connecting channels in the state of joining the two mold halves, which lead to at least two, for example 2 to 10 and preferably two openings, which is present in the mold half to be arranged on the fixed platen and by which molten metal can be filled into the mold cavity (s).

Compared with conventional casting molds, the casting molds which can be used according to the invention thus have a plurality of openings, so that cavities present in the casting mold can be replaced by several different ones Casting drives can be filled simultaneously during a casting cycle. Embodiments of molds which can be used according to the invention are explained in more detail below with reference to FIGS. 4b and 5b.

According to a preferred embodiment of the present invention, the mold comprises at least two cavities of the same dimension, which can be filled with molten metal through separate openings. This embodiment is modeled on a conventional multi-cavity mold.

According to a further preferred embodiment of the present invention, the casting mold comprises at least two cavities of different dimensions, which can be filled with molten metal through separate openings. This embodiment is modeled on a conventional combination or unit shape.

The number of cavities provided in the casting mold depends on the size of the castings to be produced and can be, for example, 2 to 10, preferably 2 to 4.

As stated above, a significant advantage of the diecasting machine according to the invention is that the casting process in the mold cavities can be carried out sequentially, ie not all of the mold cavities present are simultaneously filled with molten metal. This ensures that the explosive force during the casting process also only sequen ^¬ tially arises, namely at the positions of the just filled with metal melt ^¬ cavities.

According to a particularly preferred embodiment of the present invention, a die-casting machine is provided in which the movable clamping plate is guided along preferential way four guide columns is movable, and in addition preferably on the movable platen fastening devices, preferably clamping cylinders, are arranged for the preferably four guide columns.

A corresponding die casting machine is known from WO 2008/131571 AI. In such a die casting machine, the locking force he ^¬ required is provided by the guide columns are firmly fixed to the movable clamping plate in the closed state, preferably via arranged on the movable on ^¬ clamping plate clamping cylinder. Since preferably the passages for the four guide columns and the corresponding clamping cylinders are located at the four corners of the movable platen, the resulting forces are absorbed evenly by the movable platen and ensures stable operation of the die casting machine.

According to one embodiment of the present invention, it may be sufficient not to provide the closing force at the same time over all clamping cylinders at the same time, but only over those clamping cylinders in the vicinity of the cavity (s) filled with molten metal at the moment. For example, only cavities can be filled in egg ^¬ nem first step of the casting cycle which are located in the upper part of the mold. In this case, it may be sufficient to provide the closing force only by tensioning the two clamping cylinders at the upper corners of the movable platen. If only cavities are then subsequently filled in a second step of the casting cycle, which cavities are located in the lower part of the casting mold, then it may be sufficient to provide the closing force required for this purpose only by tensioning the two clamping cylinders at the lower corners of the movable clamping plate provide. Similarly, there may possibly be sufficient to tighten only the clamping cylinder on the left or right side of the moving platen in the jeweili ^¬ gen step of the casting cycle, that is only there to apply the full closing.

According to the invention as set forth above required than with conventional printing usually ge ^¬ ringere Schliesskrafte molding machines. This makes it possible to use according to smaller diameter guide columns and / or larger diameter clamping plates, which in turn allows the use of larger molds. According to the invention, the diameters of the guide columns can be reduced by 20-40%, preferably 20-30%, and the dimensions of the clamping plates increased by 20-40%, preferably 20-30%.

For example, it is possible with the present invention, instead of using conventional square clamping plates larger rectangular platens and thereby also to enlarge the shape. Depending on the size of the rectangular platens, it is preferable to use, for example, 6 instead of 4 Führungssäu ^¬ len to prevent bending of the platens during operation. The present invention further relates to a process for the production of castings in a die casting process, preferably with a die casting machine described above, comprising the steps

a) filling a first portion of a cavity or Kavi- activities, which is provided in a provided by two closed Formhälf ^¬ th mold or, with metal melt by means of a first drive Giessan-; b) filling a second portion of a cavity or activities of Kavi- which is provided in a provided by two closed Formhälf ^¬ th mold or, drive with molten metal by means of a second Giessan-,

c) optionally filling a further portion of a cavity or cavities, which is provided in a provided by two closed mold halves mold or are, with molten metal by means of another casting drive and

d) optionally repeating step c) to the fully ^¬ constant filling of all cavities;

wherein between the steps of filling a part of the cavity (s) a respective time delay corresponding to substantially the solidification time of the gate of the casting formed in the previous step in a part of a cavity or of cavities is maintained.

According to the invention, the term "substantially" so to be interpreted gene that encompassed deviations of ± 10% of the solidification time of the on ^¬-section of the casting formed in the antecedent step in a portion of a cavity or cavities.

The above steps are carried out according to the invention in a single casting cycle.

According to the present invention, a "casting cycle" is understood to mean a process sequence which begins with the closing of the casting mold by the beginning of the movement of the movable clamping plate in the closed position and with the removal of the casting mold

Gussstücks or castings from the open by moving the be ^¬ movable platen in the open position form ends. A casting cycle according to the invention thus comprises the steps the closure of the mold by movement of the movable platen in the closed position, ie until the mold halves touch,

tensioning the clamping cylinder and thereby applying closing force (whereby the machine in

Casting readiness is added)

the metering of molten metal into the casting chamber of a first casting set,

the filling of a first part of a cavity or of cavities, which is or are provided in the casting mold, with molten metal by means of the first casting drive, the metering of molten metal into the casting chamber of a second casting assembly, this process preferably overlapping or parallel to the casting process of the casting first casting ^¬ san drive takes place

filling a second part of a cavity or cavities provided in the casting mold with molten metal by means of the first casting drive, solidifying or cooling the molten metal in the mold; In this case, as long as heat is released to the mold until the casting has reached a sufficient for removal from the mold ^¬ reaching strength

opening the mold by moving the movable platen into position to remove the casting, and removing the casting (s) by typically synchronously ejecting and removing the casting from the mold; and

preparing the mold for the next casting cycle by means of mold spraying and optionally blowing out.

Depending on the number of casting drives used, molten metal must be metered into the casting chambers of other casting sets and from to transport there by means of the or the other Giessantriebe in other mold cavities.

The dosage of molten metal in a casting chamber of a

Casting is basically known. In the case of the preferred cold-chamber die casting method, a molten metal is usually produced in a separate container and then filled with suitable aids (for example a ladle or a dosing oven) through an opening in the casting chamber.

The filling of cavities of a mold is also known. A casting piston arranged in a casting cylinder, the other end of which is in a position in the casting chamber in which molten metal can be filled through the filling opening in the casting chamber, is moved into the casting chamber by the action of force, preferably hydraulically. The casting piston passes through the filling opening in the casting chamber and closes it against the environment. Typically, the casting piston is moved into the casting chamber in three different phases, applying different pressures and velocities. In the first phase a slower flow of the casting piston in the casting chamber is carried out until the metal ^¬ melt to the inlet into the mold cavity (ie up to the stop section) has been conveyed. In the second phase the mold cavity is very quickly (typically within 10 to 120 ms, depending on the wall thickness and the flow length) be ^¬ filled by the casting piston is moved very quickly forward. In the third phase, the so-called post-pressure phase, a high pressure (typically greater than 200 bar to 1200 bar) is applied to the casting piston, whereby the during the phase transition of the molten metal from liquid to solid in the mold cavity resulting volume loss is compensated by make-up of molten metal.

The removal of castings from the mold takes place in a manner known to those skilled in the art, for example with the aid of ejection elements.

With the inventive method, several castings can be produced in a casting cycle, and that more castings than with a conventional die casting in a casting cycle forth can be made ^¬. The exact number of castings that can be produced in one casting cycle depends on the size of the castings. The smaller the castings, the more castings are produced Kgs ^¬ nen in a casting cycle. With the die casting machine according to the invention, for example, four instead of two usually produced in a casting cycle

Shock absorber bridges, two side members instead of a conventional castable side member, or two panel carriers instead of a conventionally castable panel carrier are produced in a casting cycle.

This increase in production is carried out as above enables the fact that the existing Kavitätenräume be sequenced ^¬ tially filled with different Giessantrieben. Between the individual filling steps, a time delay is maintained, which essentially corresponds to the solidification time of the gating of the casting formed in the previous step in a part of a cavity or cavities. According to the invention, this time delay is preferably 2 to 10 seconds, more preferably 3 to 6 seconds.

According to the present invention, under a "bleed" the interface of the respective casting between casting and connecting channel understood, which is formed by solidification of the molten metal outside the mold cavity (s), ie in the connecting channels to the one or more mold cavities. The gate is removed from the casting at the end of the actual casting cycle.

It should be noted that the time for a dung inventions according casting cycle to be maintained by the temporal Ver ^¬ delay is not increased because the present invention resulting cuts are generally smaller than conventional gates and solidify faster.

According to the invention, metal melt can be metered into the casting chamber of the next casting assembly in the period of the time delay between the filling steps, with the aid of which the filling of the next part of a cavity or cavities is to take place. Most preferably, the next dosing step begins at the same time

"Shot" (filling a portion of cavities) with the help of the prior art casting drive, so that the inventive method can be performed as time-saving and efficient as possible.

As stated above, it is possible that in the steps of filling a portion of the cavity (ies) to compensate for the erfindungsge- MAESSEN method resultant explosive force by a clamping force, which (to the movable platen at the Be ^¬ reaching the filled in the respective step cavity en) is created. In particular, when a die casting machine according to WO 2008/131571 AI is used, the required closing force can be provided locally limited by the guide columns are firmly fixed to the movable platen in closed form ^¬ closed state, preferably on at the movable Chen clamping plate arranged clamping cylinder, but only on those clamping cylinder in the vicinity of the moment filled with molten metal cavity (s). For example, in a first step of the casting cycle, only cavities which are located in the upper part of the casting mold can be filled. In this case, it is appropriate, gegebe ^¬ sufficient to provide the clamping force, to provide them only by closing the two clamping cylinder at the upper corners of the movable platen. If then only cavities are filled in a second step of the casting cycle which are located in the un ^¬ direct part of the mold, it may be suffi ^¬ accordingly to provide for the necessary clamping force, if appropriate, this only by closing the two clamping cylinder at the lower corners to provide movable clamping plate.

Similarly, there may possibly be sufficient to close only the clamping cylinder on the left or right side of the moving platen in the jeweili ^¬ gen step of the casting cycle.

The inventive method is preferably controlled by means of ei ^¬ ner corresponding software, as sold, for example, by the applicant under the name Dat @ net. Preferably, each casting drive is independently controlled and regulated.

The die-casting machine according to the invention is comparatively compact, since only short distances between mold cavities and corresponding casting chambers have to be provided. This also reduces the metal consumption (less burnup, less melting) as well as the energy costs associated with melting or burning. Due to the above compact te construction also ensures gets fed that the optimum amount of metal melt ^¬ when sen erfindungsgemäs- method, each casting. In contrast to conventional die casting processes, there are no problems with multiple casts in cavities which are far away from the casting system or in an unfavorable position / position.

As a result of the significant increase in production, the die casting machine according to the invention and the method according to the invention can be used in particular for the production of castings required in large quantities. The present invention thus also relates to the use of a previously be registered ^¬ die casting machine or an above-described ^¬ NEN mold for producing cast pieces, preferably castings for the automotive industry or the electronics sector.

In particular, the present invention is for the produc- ^¬ ment of structural parts in the automotive sector of the compact or upper middle class and can thus make an important contribution to the achievement of C0 ₂ goals.

With the present invention, larger and thinner-walled components can be cast, which can meet the automotive industry's need for part integration. In particular, with the present invention, extremely large castings can be produced by casting such a component by means of several casting drives. Examples include the entire rear part of a Automo ^¬ bils, tomobil called the two longitudinal members and a cross-connection for a Au in one piece or two shock absorbers bridges connecting end wall in a casting. Analogously, the present invention also hard to be supplied, preferably made thick-walled castings ^¬, the example by a Giessantrieb as the main Giessantrieb and another Giessantrieb be used as a power supply unit for the thick-walled section.

With the present invention, components can intermittently (ie, it would in a casting cycle, a casting and to mirror ^¬ pictorial casting produced, for example on the left and right side of a vehicle to be incorporated same components) to be "just in time" manufactured. This reduces the effort for an otherwise required conversion of the die casting machine (in conventional die casting machines, the casting mold usually has to be changed for batch production).

With the present invention, castings of different metal alloys may be produced in a mold cavity, for example by a portion of the casting with a fed from a first Giessantrieb metal alloy and another portion of the casting with at ^¬ thereof, a second Giessantrieb fed metal alloy is poured. This is particularly advantageous for castings with different requirements in the various component zones (normal strength, high strength, ductile and high ductile in the crash area).

The present invention thus also relates to a casting, preferably produced by the above described procedural, characterized in that the cast piece is in one piece and comprises at least two portions which are composed of different ^¬ union materials, preferably of different metals or metal alloys , According to the invention, the Casting 2 to 10, preferably have exactly two such different ^¬ different sections. By "integral" is meant in this context that the casting is made in a single step, for example in a mold cavity during a casting process and is not made from two separately produced components ge ^¬ by subsequently joining together of the separate components.

The present invention will be explained below with reference to non-restrictive embodiments and drawings. Show it:

Fig. 1 die casting machine according to WO 2008/131571

a schematic embodiment of the die casting machine according to the invention with two vertically superimposed casting drives and Giessgarnuren Fig. 3 shows another schematic embodiment of the inventive die casting machine with two horizontally juxtaposed Giessantrieben and Giessgarnuren Fig. 4a shows a schematic embodiment of a conventional

Multi-cavity mold

4b shows a schematic embodiment of a multicavity casting mold according to the invention

Fig. 5a shows an embodiment of a conventional combination casting mold 5b shows an embodiment of a combination casting mold according to the invention

In Fig. 1, a conventional die casting machine is shown, as described for example in WO 2008/131571 AI. According to the invention, such a die-casting machine is preferably equipped and used with at least two casting drives and correspondingly at least two casting sets. In Fig. 1, a two-plate horizontal die casting machine is ge shows ^¬ which a machine bed 1 with a perpendicular to it being ^¬ arranged fixed platen (FAP) 2 on, and a on the machine bed 1 slidably movably arranged movable on ^¬ bolster plate (BAP) 3 having.

The BAP 3 has a, preferably closed frame with two feet 7, struts 5 and ribs 6 and an ejector unit 14 for ejecting molded components. At FAP 2 and BAP 3 are each a mold half of a mold 16 are arranged. The BAP 3 is guided in four columns 8, which in turn are stored in the FAP 2. There are two upper and two lower columns 8 are provided. Each column 8 is a, arranged on the BAP clamping device 9 to ^¬ ordered, by means of the closing force is applied to the je ^¬ particular column 8 during firing. The pillar protection tube 4 integrated into the BAP 3 prevents contamination of the column toothing. Between the lower columns 8 a lock cylinder 10 is provided. Column ejection cylinders 13, which are arranged or fastened to the latch 11 or the BAP 3, are arranged on the column coupling 12. Furthermore, a drive group 15 is provided on the machine bed 1.

In Fig. 1, the casting drive of the die casting machine is not ge ^¬ shows. FIG. 2 shows an embodiment of the pressure casting machine according to the invention with two vertically stacked ones

Casters and Giessgarnituren shown, which are arranged on a die casting machine according to FIG. 1. The same reference numerals in Figs. 1 and 2 denote the same components.

On the formabgewandten side of the fixed platen 2, two casting chambers 19a and 19b are arranged vertically one above the other. The casting chamber 19a contains the end of a casting piston whose other end is arranged in a casting cylinder 18a and can be hydraulically operated there. The casting chamber 19b contains the end of a casting piston whose other end is arranged in a ^casting cylinder 18b and can be hydraulically operated there. The casting chambers are in this embodiment symmetrically around the center of the fixed platen 2 angeord ^¬ net and secured in corresponding recesses in the fixed platen 2. However, it should be emphasized again that the casting chambers can always be located anywhere on the fixed clamping plate in the area between the guide columns. The exact configuration of the diecasting machine according to the invention can be adapted depending on the casting to be produced. A here only schematically indicated component 17 represents the üb ^¬ rigen components of the casting drives (hydraulic drive).

In Fig. 3 shows a further embodiment of the erfindungsgemäs ^¬ sen die casting machine with two horizontally arranged adjacently ^¬ Giessantrieben and Giessgarnituren is shown, which are arranged on a die casting machine according to FIG. 1. The same reference numerals in Figs. 1 to 3 denote the same components. In Fig. 3 the casting chambers are arranged side by side symmetrically about the center of the fixed platen 2 and fixed in ent ^¬ speaking recesses in the fixed platen 2.

FIG. 4 a shows a schematic embodiment of a conventional multi-cavity casting mold 20. The casting mold has a plurality of (here 6) identical cavities 21 whose dimensions correspond to the dimensions of the castings to be produced. The cavities 21 are connected to one another and to an opening 23 via connection channels 22. The opening 23 is for Giessantrieb open when the mold is being ^¬ belongs to the die casting machine 20, and can be filled with molten metal from Giessantrieb. From the opening 23, the molten metal under pressure flows through the connection channels 22 into the cavities 21.

FIG. 4b shows a schematic embodiment of a multicavity casting mold 24 according to the invention, wherein identical reference symbols in FIGS. 4a and 4b denote the same components. The inventive mold 24 includes two Öffnun ^¬ gen 23a and 23b, which are in contact with cavities 21a and 21b via respective connecting channels 22a and 22b. Each of the openings 23a and 23b is open to one of the casting drives, when the mold 24 is arranged in the die casting machine, and can be filled with molten metal from these casting drives. From the openings 23a, 23b, the molten metal under pressure flows through the connection channels 22a, 22b into the cavities 21a and 21b.

In the mold 24 according to the invention more cavities 21a and 21b can be provided than in the conventional mold 20. In FIG. 21a and 21b, but as noted above, the number of possible cavities 21a and 21b may vary. In the inventive mold 24 according to FIG. 4b, the upper cavities 21a can be filled independently of the lower cavities 21b by a separate casting drive, and vice versa.

FIG. 5 a shows an embodiment of a conventional combination casting mold 25. The casting mold has a plurality of (here 3) identical cavities 21 and a cavity 26 different therefrom, the dimensions of which correspond to the dimensions of the castings to be produced. The cavities 21 and 26 are connected to each other and to an opening 23 via connecting channels 22. The opening 23 is open to the casting drive when the casting ^¬ form 25 is arranged in the die casting machine, and can be filled by the casting drive with molten metal. From the opening 23, the molten metal under pressure flows through the connection channels 22 into the cavities 21 and 26.

FIG. 5b shows an embodiment of a combination casting mold 27 according to the invention, the same reference symbols in FIGS. 5a and 5b designating the same components. The casting mold 27 according to the invention has two openings 23a and 23b, which are in contact with cavities 21 and 26 via respective connecting channels 22a and 22b. Each of the openings 23a and 23b is open to one of the casting drives, when the mold 27 is arranged in the die casting machine, and can be filled with molten metal from these casting drives. Of the Publ ^¬ voltages 23a, 23b of the pressurized metal ^¬ melt flows through the communication ports 22a, 22b into the cavities 21 and 26th

In the case of the casting mold 27 according to the invention, more cavities 21 can be provided than in the case of the conventional casting mold 25 FIG. 5b shows schematically and exemplarily 4 cavities 21, but as stated above, the number of possible cavities 21 can vary. 27 In addition, the inventive Giess ^¬ form a larger cavity 26 than the conventional mold 25. In the inventive mold 27 according to Fig. 5b, the right cavities 21 can be filled by a separate Giessantrieb independent of the left cavity 26, and vice versa ,

Claims

claims

1. Die casting machine, comprising a movable platen (3) and a fixed platen (2), one on the bewegli ^¬ Chen platen (3) arranged mold half (16) and ei ^¬ ne on the fixed platen (2) arranged mold half (16) , characterized in that the die casting machine at least two, preferably two Giessantriebe (17, 18a, 18b) and an analog number of the Giessantrieben (17, 18a, 18b) zugordnete Giessgarnituren (19a, 19b).

2. Die casting machine according to claim 1, characterized in that the two or each two casting drives (17, 18 a, 18 b) are arranged horizontally next to each other or vertically one above the other or diagonally, preferably symmetrically about the center of the rear surface of the fixed platen (2).

3. Die casting machine according to claim 1 or 2, characterized in that the merging of the two mold halves (16) formed mold (25, 27) at least one, preferably a plurality of cavities (21, 21 a, 21 b, 26) ready ^¬ provides, wherein the Mold has at least two, preferably two openings (23a, 23b), via which the Giess ^¬ form (25, 27) through the at least two, preferably two casting drives (18a, 18b) can be filled with molten metal.

4. Die casting machine according to one of claims 1 to 3, characterized in that the fixed platen (2) Ausspa ^¬ ments and / or fastening devices for the at least two, preferably two Giessgarnituren (19 a, 19 b).

5. Die casting machine according to one of claims 1 to 4, characterized in that the movable clamping plate (3) ent ^¬ long of, preferably four, guide columns (8) is movable.

6. Die casting machine according to claim 5, characterized in that on the movable platen (3) fastening devices, preferably clamping cylinder (9), for the, preferably four, guide columns (8) are arranged.

7. Die casting machine according to one of claims 1 to 6, characterized in that the die casting machine is selected from the group consisting of a hot chamber die casting machine, a cold chamber die casting machine, a hot chamber vacuum die casting machine, and a cold chamber vacuum die casting machine, wherein it is can each act around a vertical die casting machine or a horizontal die casting machine.

8. mold (25, 27) for a die casting machine, preferably a die casting machine according to one of claims 1 to 7, constructed from two mold halves (16) which at least one, preferably several cavities (21, 21a, 21b, 26) provides characterized in that the casting mold (25, 27) at least two, preferably two Öff ^¬ openings (23a, 23b) comprises, via which the mold (25, 27) can be filled with molten metal.

9. Casting mold according to claim 8, characterized in that the casting mold (25, 27) comprises at least two cavities (21a, 21b) of the same dimension, which can be filled with molten metal by separate openings (23a, 23b).

10. Casting mold according to claim 8, characterized in that the casting mold (25, 27) comprises at least two cavities (21, 26). different dimension, which are filled by separate openings (23a, 23b) with molten metal.

11. Casting mold according to one of claims 8 to 10, characterized in that for each opening (23a, 23b) a Giessgarni- structure (19a, 19b) is provided.

12. A method for producing cast parts in a pressure casting method, preferably with a die casting machine according to one of claims 1 to 7, comprising the steps a) filling a first part of a cavity or cavities (21, 21a, 21b, 26), which mold provided in a two ge ^¬ connected mold halves (16) (25, 27) is provided or with the molten metal by means of a first Giessantriebs (17, 18a, 18b); b) filling a second portion of a cavity or cavities (21, 21a, 21b, 26), which mold provided in one (by two ge ^¬ connected mold halves 16) (25, 27 is provided) or, with metal melt by means of a second Giessantriebs (17, 18a, 18b), c) optionally filling of a further part of a Kavi ^¬ ty or cavities (21, 21a, 21b, 26) which bereitge ^¬ presented in egg ^¬ ner (by two closed mold halves 16) mold ( 25, 27) is provided or, with molten metal by means of a further casting drive (17, 18 a, 18 b) and

d) optionally repeating step c) to the fully ^¬ constant filling of all cavities (21, 21a, 21b,

26);

wherein between the steps of filling a portion of the cavity (ies) (21, 21a, 21b, 26) each have a time delay deferrers ^¬ corresponding substantially to the solidification time of the gate of the antecedent part of a step in a Cavity or from cavities (21, 21 a, 21 b, 26) formed casting is observed.

13. The method according to claim 12, characterized in that in the steps of filling a portion of the cavity (s) (21, 21a, 21b, 26) resulting explosive force by a

Closing force is compensated, which is applied to the movable platen (3) at least in the region of the filled in each step cavity (s).

14. The method according to claim 13, characterized in that the closing force to the movable platen (3) in Be ^¬ rich filled in the respective step cavity (s) (21, 21a, 21b, 26) is applied by fixing guide ^¬ columns (8) on the movable platen (3), preferably ^¬ by clamping cylinder (9).

15. The method according to any one of claims 12 to 14, characterized in that the time delay between the respective steps of filling a portion of the cavity (s) (21, 21a, 21b, 26) 2 to 10 seconds, preferably 3 to 6 seconds is.

16. The method according to any one of claims 12 to 15, characterized in that castings are produced in sets, and thus in a casting cycle, a casting and spie ^¬ gelbildliches casting are produced.

17. casting, preferably produced by a process according to any one of claims 12 to 16, characterized in that the casting is in one piece and at least two Ab ^¬ sections comprises, which are constructed of different materials, preferably different metals or metal alloys. Use of a Druckgiessmaschme according to one of the claims ^"che 1 to 7, or a casting mold (25, 27) according to one of claims 8 to 11 for the manufacture of castings, castings, preferably for the automobile sector or the electronics sector.