WO2008122275A1

WO2008122275A1 - Multiple cavity mold

Info

Publication number: WO2008122275A1
Application number: PCT/DE2008/000575
Authority: WO
Inventors: Hermann Rausch
Original assignee: Hermann Rausch
Priority date: 2007-04-07
Filing date: 2008-04-04
Publication date: 2008-10-16
Also published as: DE112008001534A5; EP2134524A1; DE102007016576A1

Abstract

The invention relates to a multiple-cavity mold for sequentially producing a one-piece 'continuous element' from successively arranged, identical cast parts, consisting of at least two individual female molds that are complementary to the cast part and that are interlinked by respective runners to form respective fillets. A second, identical runner is joined to one of the two outer individual female molds, the respective junction and the respective direction of the two runners for both outer individual female molds being identical. The second runner is open at least to the side opposite its point of placement and its open end can be closed by a closure.

Description

Anreihgussform

The invention relates to a line-up casting mold for the sequential production of one-piece "endless elements" of multiple juxtaposed, identical castings, consisting of at least two negative single molds complementary to the casting, which are each connected to each other by a connecting channel for forming a connecting web ,

According to the current state of the art, "endless elements" are used in great numbers, including profiles that can be produced almost endlessly "by the meter" - for example, by extrusion, elements that can be aligned without restriction, such as drive chains, and material feeds to automatic production machines in which identical elements are applied to a carrier tape and fastened there by gluing, riveting, welding or other technology.

Likewise known prior art is that plastic or metal small parts, such as retaining clips, required in large numbers,

Klipse-, dowels, spacer plates or brackets together with a connecting bar between two small parts of the same material cast, pressed or cut, are introduced in the next step in the processing machine and there divided into the small parts to be used and the disposal webs to be disposed of handling equipment , In this case, these multiple strips of material usually only a limited length, which is limited by the size of the manufacturing form. This results in relatively small units that require frequent changes in the material supply. For plastic parts, DE 3640984, for example, describes one of the many methods with which regularly recurring castings are sprayed around a carrier tape. Characteristic is the carrier tape, which must be supplied from the outside, so for a principle endless part so is always new to enforce. This joint is not only an additional thickening, but also a production engineering handicap. Another disadvantage is that the carrier tape within the processing machine can only be severed with some effort, since it must be so strong that it moves all the molded parts without tearing the carrier tape, but has no predetermined breaking points predetermined by notches or other constrictions.

Against this background, the object of the invention is to provide a device and to define a method by which the production of a continuous material strip with regularly recurring castings from a single, homogeneous material with only a single mold according to the usual methods for casting, such as injection molding, is possible. The method should be suitable for plastic as well as for all other materials that shrink after the first curing in the form not at all or only very slightly. It should be possible to use materials which are either thermoplastically deformable, ie brought into a liquid physical state by repeated heating, or of materials which harden irreversibly after curing, for example two-component plastics.

As a solution, the invention proposes a Anreihgussform, consisting of at least two negative single forms, which are connected by a respective connecting channel for forming a respective connecting web, characterized in that at one of both external negative individual forms a second, identical connecting channel is attached, wherein the respective starting point and the respective orientation of the two connecting channels for both outer negative single forms is identical and the second connecting channel is open to the outside at least on its side opposite the starting point and there is closed by a closure.

This mold is built according to the experience and knowledge that are known for the casting of the desired material, ie thermoplastics, multi-component plastics, metals or composite materials, such as a mixture of wood chips and plastic. These include corresponding filling openings, vents, the observance of minimum cross-sections, which allow access of the liquid casting compound into all

Areas of the mold enable cooling or heating devices, the shaping without undercuts above or below the dividing line of the molded parts or additionally insertion elements for undercuts and tools for removing the resulting cast element. All these details correspond to the current state of the art and are well known to those skilled in the art, which is why they need not be further explained in this patent application.

The basic idea of this invention is that the entire casting element consists of at least two identical castings, which are connected to one another by a connecting web. The mold for each casting is referred to as a negative single mold. In a line-up according to the invention thus at least two negative single forms are included. These two negative single forms must be connected to each other with a connecting channel be connected, which serves to form the connecting web between the two castings. The basic idea of the invention will be explained with reference to this exemplary embodiment of the line-up casting mold with the minimum number of two negative single forms. It is the hallmark of this invention that at one of the two outer negative single forms a second connecting channel is set, which is identical to the first, inner connecting channel, with "identical" here not only a same shape is meant, but also the same starting point at the This second connecting channel leads to the outside of the box casting mold and is opened there, wherein it is important that it is in fact absolutely identical to the inner connecting channel, except that an extension of the channel is possible. that the second connection channel is shorter than its counterpart inside.

Only then is the inventive use of the Anreihgussform possible. The proposed method consists of three steps. In the first step, the line-up casting mold is closed and poured out with a closure in the connecting channel leading to the outside. In the second step, the resulting cast element is removed and offset by a cast element inserted back into the mold. For this purpose, the closure must be removed, because only then the outwardly leading connecting channel provides space for the connecting web, which has previously been created inside the Einreihgussform. As a result, the connecting web formed on the inside seals the outwardly pointing connecting channel. At the same time, he holds the attached second cast part firmly so that it floats on the outside of the closed batching mold. In the interior of the mold, in this second step, one of the two negative single molds is filled with a finished cast part - only the one is free inner connecting channel and the adjacent negative single form. When these two cavities are poured out, a casting element is created, which now consists of three identical cast parts, which are each connected to one another by connecting webs. In turn, this part can be inserted into the line-up casting mold by one casting so that the next, the fourth casting can be molded.

In this way, a principle endless casting element of a not limited in principle number of identical castings, which are always repeated.

For the principle of the invention, it is not relevant whether partially flexible materials are used which can be rolled up or whether the materials are so little flexible that they can only be cut to length as a profile. Likewise, it is conceivable that the connecting webs take over only the function of a transport medium and a feed aid and are therefore removed again in a processing machine.

Another possible embodiment relates to endless elements in which the connecting webs between the individual cast elements count to the desired shape and / or functionality and are therefore used with. Conceivable applications would be picture frames and stucco moldings with regularly recurring, plastic decorative elements, toothed racks, cam strips or handles.

It is also conceivable that the "endless element" for use has to be bent in some places, for which notches can be provided which serve as nominal knee points. The use case would be edge strips in the housing area, which should cover a floor or ceiling covering at the edge. In these cases, the material should be chosen so that it despite the de-. formation still retains a stable connection at the kinks. Then a circular arc segment can be approximated by polygons. Another alternative is that the material is so flexible that it is continuously bendable.

If the end product is to be bent very frequently like a chain, it must again be checked whether the material meets the requirements

Number of bending cycles can endure. If a reinforcement of a second, very flexurally elastic, but tensile material is required, such a reinforcement can also be incorporated into the Anreihgussform invention. When the end of this amplification is reached, another section has to be attached, for which, according to the current state of the art, numerous methods are known, which are also applicable here.

In a further variant, which in practice probably hitherto occurred frequently, the line-up casting mold according to the invention will contain not only the negative single molds for two castings, but additional cavities (sometimes also called mold cavities) which will be between those negative single molds equipped with two connecting passages are inserted in the inner connecting channel. These cavities can be identical to the outer negative single molds and also the connection channels can be made identical in terms of shape and orientation. Another conceivable alternative is that the additional cavities inserted between the outer negative single molds are identical negative individual molds, but are connected to one another by other and / or curved connecting webs. As a result, the manufacturer •

It is possible to form an "endless element" that is curved in the mold parting plane.

It is even conceivable the production of an annular cast element. To close this ring, however, it is necessary that both outer negative individual shapes of the line-up mold have an outwardly open connection channel. In the case of partially flexible casting material, it is possible to close the almost finished cast element in such a way that both the left and the right negative mold are equipped with the two end castings of the casting element which has been preformed so far. In a last step, the connecting channel is then poured out and thereby connects the two terminal castings of the cast element.

As a further, advantageous embodiment, the invention proposes that the connecting channel, which is open towards the outside, can either be heated or cooled. This is particularly advantageous when using thermoplastic materials: in the first step, the connecting channel open to the outside can be optimally poured out. In the second step, if in this connection channel an already cast connecting web is inserted, it is advantageous if this connecting web is well cooled so that it is so stable that it attached to the outwardly projecting casting and all other connecting webs and castings who can hang on it can safely wear.

When using thermoplastics or when pouring with metals, the freshly cast connecting web connects at the end of the connecting channel with the inserted in the negative single mold casting by the partial re-liquefaction of the otherwise finished molded casting, which a firm and strong connection between the new connecting web and the old, already cast in the previous step casting arises.

For materials in which this re-liquefaction is not possible, the invention proposes that the casting provided with only a single connecting web at its later point of contact with the second connecting web to be added in the next step, a connecting blind hole is formed. In the next step, the liquid material can flow into this connection blind hole, thereby forming an intimate connection of the connecting web with the casting. In particular, in cases where the liquid material does not bond firmly to the already hardened material of the casting by partial dissolution, it is expedient to provide the connection blind hole at its inner end with at least one thickening projecting beyond the cross section of the inlet opening , This thickening prevents the cast-in connecting web from slipping out of the cast part under tensile load. For production, a two-part insert mold is known in the art.

For flexible and / or partially flexible materials, it is a further advantageous embodiment, when the thickening is formed as a re-hook, because then even in the case of a resulting high tensile stress dilution of the connecting web, the cast-in end can not slip out of the connection blind hole. In the following, further details and features of the invention will be explained in more detail by way of examples. However, these are not intended to limit the invention, but only to explain. It shows in a schematic representation:

Figure 1 lower half of a batching mold with two negative single forms

FIG. 2 as in FIG. 1, but with a cast element which has already been cast and has been relocated around a casting

Figure 3 as Figure 2, but with a connection blind hole in the outer casting

The figures show in detail:

FIG. 1 shows the lower half of a casting mold for a cast element, which in this example consists of two, approximately cylindrical, cast parts 1, which are connected to one another via a connecting web 5. This casting is not shown in FIG. 1, but only the respective lower half of the negative single mold 11 complementary to the cast part and the connecting duct 2 complementary to the cast web. In the left part of the image, the negative single mold 11 is shown, which is only connected to a single connecting duct 2. In the right-hand part of the image, an identical negative single-form 11 can be seen, which is connected to a connecting channel 2 on both sides. In this case, the right to be recognized connecting channel 2 is brought up to the outer edge of the Anreihgussform. From the starting point 12 on the negative single mold 11 to the edge of the casting mold, the outwardly pointing connecting channel 2 shown on the right is absolutely identical to the inner connecting channel 2. In the illustrated configuration, the outwardly facing connecting channel 2 is closed by a closure 3. This configuration is needed for the first step of the casting process, where the initial part of the "endless element" is made.

In Figure 2, the same Anreihgussform is drawn as in Figure 1, but here with an already cast cast element, which is already taken from the Anreihgussform and offset by a Negativeinzel- form inserted again.

In Figure 2 it is understood that the connecting web 5 between. the two castings 1 is inserted into the outwardly leading connecting channel 2 and this completely fills and seals. Likewise, in the negative individual form shown on the right

11 a casting 1 is used, which also completely fills this negative single mold 11 and thereby prevents the further penetration of casting material from the connecting channel 2.

If the still free negative single mold 11 is charged with the liquid material, it can be understood in FIG. 2 how the liquid filling of this cavity with further increase of the liquid level also runs into the connecting channel 2 and reaches the front end side of the casting 1. As a result, the liquid material wets the front of the already cast castings

1 and melts them, whereby an intimate connection between the otherwise rigid casting 1 and the liquid material in the connecting channel 2 is formed. With this step of the production, therefore, a further connecting web 5, which is fused to the previously cast casting 11 and at the other

End another casting 1 carries. In Figure 2 it is clear that in this case a cast element is formed, which consists of a total of three pieces of castings 1. This casting element can in turn be lifted out of the line-up casting mold and inserted further around a negative single mold 11, so that the next casting 1 can be formed over a further connecting web 5. In principle, this process can be continued without interruption, creating an "endless element".

In Figure 3, the same, lower half of the Anreihgussform is shown, which can also be seen in Figures 1 and 2. The difference is the insert 6, which projects into the negative single mold 11. In the embodiment illustrated, the insert 6 is even formed in two parts, one part of the insert 6 having an outwardly directed barb which has a thickening 41 at the inner end of the insert In order to be able to detach this undercut from the part 1 after casting, the division of the insert 6 into two sections is necessary.

For demolding, the front portion is pulled out in the first step and moved in the second step, the rear portion with the barb forward and only then pulled laterally from the casting 11. In FIG. 3, a cast part 1 with a connection blind hole 4 can be seen in the middle of the picture. With dashed lines, the thickening 41 is located at the inner end of the connection bag hole 4.

In FIG. 3, it is plausible that liquid material also flows into the connecting blind hole 4 via the connecting channel 2 and closing thickening 41 flows in and hooked after cooling or hardening in the connection bag hole 4 and in particular in the thickening 41. Even in the event that no force-fluid connection is established within the connection bag hole during cooling or hardening, the barb remains as a geometric element which allows the transmission of tensile forces from the connecting web 5 to the adjoining casting 1. In this way, castable materials can be joined together, in which otherwise no force-locking connection is generated by applying the liquid state of matter to the same material in the solid and cured state.

LIST OF REFERENCE NUMBERS

I cast part

II Negative single shape, complementary to casting 1 12 Starting point of connecting channel 2 to negative single mold 11

2 connecting channel, connects two negative single forms 11

3 lock, for second, outwardly open connection channel

4 connecting blind hole, in negative single mold 11 41 thickening, at the inner end of the connecting blind hole 4

5 connecting bridge, connecting two negative single forms 11

6 insert mold, for the preparation of the connection bag hole. 4

Claims

W 214Patent claims

1. In-line casting mold, for the sequential production of a one-piece

5 "endless element" of multiple juxtaposed, identical

Castings 1, consisting of at least two, complementary to the casting 1 Negative Einzelformen 11, which are interconnected by a respective connecting channel 2 for forming a respective connecting web 5 10 characterized in that a second, identical connecting channel 2 is attached to one of the two outer negative single molds 11 , in which

- The respective starting point 12 and the respective orientation of the two connecting channels 2 for both outer negative single forms 11th

15 is identical and

- The second connecting channel 2 is open to the outside at least on its side opposite the starting point 12 side, and

- There is closed by a closure 3.

20

2. Arrangement according to the preceding claim, characterized in that in the interior between a connecting channel 2 and a negative single mold 11, which is connected to two connecting channels 2, further pourable cavities are inserted

25

3. An array according to claim 2, characterized in that the cavities to the negative single mold 11 and the connecting channels 2 are identical.

30

4. Anreihgussform according to one of the preceding claims, characterized in that the second, outwardly open Verbiridungskanal 2 is optionally heated and / or cooled.

5. An array according to any one of the preceding claims, characterized in that within that, outer negative single mold 11, which is connected only to a single connection channel 2, at the point where attaches to the other negative 11 in the second connecting channel 2, the insert form 6 for a connection hole hole 4 is added.

6. An in-line casting mold according to claim 5, characterized in that the connecting blind hole 4 has at its inner end at least one projecting beyond the cross section of the inlet opening thickening 41.

7. Ankranggussform according to claim 6, characterized in that at least one of the thickenings 41 is formed as a barb.

8. A method for the sequential production of one-piece "endless elements" of multiple juxtaposed, identical

Cast parts 1 by means of a Anreihgussform according to one of the preceding claims, characterized in that

- In the first step, the Anreihgussform is closed with the shutter 3 and poured out and - in the second step, the resulting cast element is removed and that end casting 1 this Element, which has only a single connecting web 5 is inserted into the outer negative single mold 11, which. Is connected to two connecting channels 2, for which the shutter 3 must be removed and in the third step, the second step is repeated until the desired total length of "Endless elements" is achieved.