EP1990165B1 - Pressing arrangement with a press mould, press mould for pressing material into an article and use of such pressing arrangement, resp. press mould - Google Patents

Description

The invention relates to a press arrangement with a press mold for pressing material to be pressed into an article according to the preamble features of claim 1, or to a press mold according to the preamble features of claim 2.

Out DE 35 12 852 C2 a press arrangement with a press mold for pressing pressed material into an article, in particular into a ceramic article such as plates or the like, is known. The material to be pressed usually consists of powdery or granular, preferably ceramic, material. The press arrangement has a first and a second molded part, each with an edge section. On the inside of the molded parts, an article space is formed between them in a closed position, the article space being closed in the lateral direction by the edge sections of the molded parts which abut against one another in the closed position. An adjustment device is used to adjust the first and / or the second molded part along an axis of movement relative to one another into the at least partially closed position for filling the article space with the pressed material and for pressing the pressed material to form the article or to adjust the first and / or the second Molded part relative to each other in a spaced-apart position for removing the pressed article. A control device is used to control the movement of the adjusting device, in particular to control hydraulic pistons to adjust the molded parts, to act on a press membrane arranged on one of the molded parts and to adjust a so-called filling ring. The filling ring extends on the outside around at least one of the two molded parts and has a filling opening for feeding in pressed material and a Ventilation opening for venting the article space when filling.

The individual components for pressing the pressed material into an article are controlled by the control device in accordance with the method. In a first step, the first and the second molded part are moved relative to one another into an at least partially closed position, whereupon the article space is filled with the material to be pressed. The two molded parts are preferably aligned in such a way that the article space extends with a longitudinal axis from bottom to top, so that the material to be pressed can be poured into the article space from above. The filling ring and / or one of the molded parts are then adjusted to completely close the tool or the press mold. The material to be pressed is then pressed into the article. After the pressing, the first and / or the second molded part are adjusted relative to one another into a spaced-apart position for removing the pressed article, the filling ring being moved together with the directly adjacent molded part. Due to the preferred alignment of the press mold, the article slides downward out of the spaced-apart molded parts onto a conveyor belt arranged below. The release of the article from the molded parts is done automatically by the relief and the resulting expansion of the article.

The problem with articles manufactured in this way is that they have a circumferential ridge. Such a circumferential ridge is formed in the area in which the two edge sections of the first and the second molded part bear against one another in the closed position. In addition, a ridge usually forms, which extends in the area for filling and for venting in the lateral direction away from the edge of the article. This makes extensive post-processing necessary. It is known to provide a separate machine, which such manufactured article is supplied to press off such a burr before the article is fed to a finishing station for cleaning and sponging.

EP 0 197 415 B1 describes a press arrangement in which a first and a second molded part can only be moved so far towards one another that a small axial annular gap remains between the edges of their end faces, with an axially protruding annular edge on one of the molded parts in the direction of the opposite molded part through an axially directed outer projection is supported, on which an annular part is radially outwardly displaceable. The annular part has at least one vacuum connection for applying a vacuum to the axial annular gap. The vacuum connection is laterally axially offset from the axial annular gap remaining at the edge of the molded parts when the press arrangement is closed and is connected to this via an annular clearance. When a negative pressure is applied, air and powder are thus sucked from the article space through the small axial annular gap essentially radially outward, then the air is sucked through the area of the annular clearance between the radially lateral molded part wall of the molded part and the annular part, axially parallel to the vacuum connection. As soon as the annular gap is clogged by large particles of the powder to be compressed, only air remaining in the article space is sucked out of the article space. Inevitably, an at least narrow press burr that extends over the entire outer circumference of the press arrangement is still formed on the circumference of the article being produced.

EP 0 563 577 B2 describes a press arrangement or press mold according to the preamble of claim 1 or claim 2, in which on the first and / or second molded part in the area of the annular gap serving as a ventilation gap a device for adjusting the clear width of the ventilation gap independently of a setting an axial dimension defining a fragment thickness of the article Article space is provided. This is used to be able to vary a distance between the two molded parts relative to one another, for example when finer or coarser material to be pressed is poured into the article space in order to be able to always press the same article thickness despite the different material. Such an adjusting device for the clear width of the ventilation gap is intended to ensure that the ventilation gap has a width or width of 0.3 mm or, in exceptional cases, a slightly larger or smaller width can be set. It is assumed that approx. 93% of the granulate to be filled into the article space has a grain spectrum between 0.1-0.5 mm. Due to the design, a concavely narrowing structure of the ventilation gap up to a circumferential, wider ventilation groove arises between the membranes, which form the ventilation gap between them on the two molded parts opposite one another. Until a filter effect occurs with a width of 0.3 mm of the ventilation gap and a predominant grain size or granulate size between 0.1 and 0.5 mm, however, even with such an arrangement, so much granulate gets into the space of the ventilation gap that the demolded article has a circumferential ridge.

Another disadvantage is that in particular such a membrane, which is pressed for isostatic pressing of the article in the article space with a pressure medium from a wall of the actual molded part against the powder or granulate filled into the article space, must be firmly clamped in the edge area. Usual arrangements are constructed in such a way that the membrane is guided from the article space over the edge of the molded part, forming the ventilation gap, to the radial outside of the molded part, where it is angled by 90 ° along an outside of the molded part. In addition, one end section of this angled section of the membrane is again angled by 90 ° in the radially outward direction.

This outer section of the membrane is clamped in the radial effective direction between the external clamping element and the side wall of the molded part and also clamped by the clamping element in an axially parallel direction to the pressing direction by means of a clamping element lying on the outside, in order to provide sufficient hold during pressing. This end section of the membrane, which is angled twice by 90 °, is made wide or thick, so that a disadvantageous amount of membrane mass is required to produce the membrane. In addition, in such an arrangement, the assembly of the membrane is disadvantageously complex, since it has to be attached to the molded part or in the arrangement by means of the guide, which is angled at least twice by 90 °, with correspondingly complex assembly steps.

The object of the invention is to propose a press arrangement with a press mold or a press mold for pressing material to be pressed into an article, which require less post-processing. In particular, at least a predominant portion of the circumference of the article should be designed burr-free, so that the article in this burr-free circumferential area can only be smoothed by blurring and freed from any burrs. Another object of the invention is to be able to save material in the production of at least one of the membranes and to simplify the membrane assembly.

This object is achieved by a press arrangement with the features of claim 1, or by a press mold with the features of claim 2, or by use with the features of claim 16. Advantageous configurations are the subject of dependent claims.

This is based on a press arrangement with an isostatic press mold for pressing pressed material to form an article, having a first molded part with a Edge portion, a second molded part with an edge portion, an article space which is formed in a closed position between the molded parts and their edge portions, an adjusting device for adjusting the first and / or the second molded part relative to one another in an at least partially closed position for filling the article space with the material to be pressed and for pressing the material to be pressed into the article and for adjusting the first and / or the second molded part relative to one another into a spaced-apart position for removing the pressed article and a control device for controlling the movement of the adjusting device.

The isostatic press mold is used to press material to be pressed into an article in a press arrangement, the press mold having a first mold part with an edge section, a second mold part with an edge section, an article space which is formed in a closed position between the mold parts and their edge sections, and Attachment areas, e.g. clamping surfaces or threaded pieces for an adjusting device for adjusting the first and / or the second molded part relative to one another in an at least partially closed position for filling the article space with the pressed material and for pressing the pressed material to the article and for adjusting the first and / or of the second molding relative to one another in a spaced-apart position for removing the pressed article.

Both in such a press arrangement and in such a press mold, a filling space leads from outside the first molded part and the second molded part through at least one peripheral portion of the edge portions of the first molded part and the second molded part, with a distance between the first molded part and the second molded part that is sufficiently wide for filling in a pressed material the second molded part into the article space, and a remaining peripheral region of the mutually opposite edge portions of the first molded part and of the second molded part has a ventilation gap for venting the article space.

Both the press arrangement and the press mold also have an elastic membrane which is attached to the first molded part via its surface facing the second molded part with a clamping area of the membrane on the outside outside of the article space, and a membrane which is attached to the second molded part above its first molded part is arranged facing surface, wherein in the area of the filling space a membrane thickness of at least one of the membranes is reduced and / or a rear surface of the membrane of the first molded part is recessed.

Such a press arrangement or press mold is preferred in which the remaining circumferential area of the edge sections of the first molded part and the second molded part form the ventilation gap with a width equal to or less than 0.3 mm, in particular equal to or less than 0.25 mm, preferably equal to or less than 0, 17 mm for venting the article space.

In addition, such a press arrangement or press mold is preferred in which the at least one peripheral section of the edge sections of the first molded part and the second molded part has the filling space with the wide distance between the first molded part and the second molded part equal to or greater than 2.5 mm, in particular equal to or greater than 2.5 mm 3 mm.

The at least one circumferential section of the edge sections of the first molded part and the second molded part has the filling space with preferably the wide distance between the first molded part and the second molded part of less than 6 mm, in particular equal to or less than 5 mm.

The filling space in the at least one peripheral section of the edge sections of the first molded part and of the second molded part preferably extends over a circumferential section of less than 31 °, in particular less than 16 °, preferably less than 8 ° of the circumference of the circumferential section.

A press burr is deliberately left in such a small circumferential area, which has to be removed by post-processing. However, this allows the ventilation gap to be kept so narrow in the rest of the circumferential area that no press burr, or no press burr, which interferes with post-processing, is formed in its area. Viewed overall, however, a pressed part can be deburred more quickly and with less effort if only a limited circumferential area has a press burr. In addition, even if the remaining press burr is excessively thick, there is a significant saving in material for the press material, since no press burr that consumes press material is formed on the article over the by far largest circumferential area.

The filling space and the ventilation gap are preferably spaced apart between them by a configuration of a region separating them in terms of flow technology.

In particular, the first and the second molded part for filling with the material to be pressed and for pressing the material to be pressed into the article are arranged in a closed position relative to one another, in particular in the same closed position. This also eliminates a process step of initially only partially closing, since the two molded parts are completely closed directly. This step advantageously prevents the pressed material from penetrating into the ventilation gap.

In the press arrangement, the control device can be designed to suitably set at least one receiving volume for the material to be pressed and / or a width of the article space between the first molded part and the second molded part by applying a correspondingly dimensioned pressure in a pressure space between a surface of the first molded part and the above the elastic membrane facing the second molded part and attached to the first molded part.

In combination with the above features, it can be assumed that an isostatic press mold for pressing pressed material into an article, in particular a press mold according to a preceding claim, comprising a first molded part with an edge section, a second molded part with an edge section, an article space which is in a closed position is formed between the molded parts and their edge portions, and at least one elastic membrane which is attached to the first molded part via its surface facing the second molded part with a clamping area of the membrane on the outside outside of the article space, the clamping area of the membrane firmly against the surface of the first Part or clamped to a component attached to it. The clamping area of the membrane has at least one membrane projection which is pressed into a receiving opening in the surface of the first molded part, and the clamping area in the outside direction of an article plane as seen from the article space has at least one deflection of the membrane in the direction of the first molded part by less than 80 ° having.

The deflection of the membrane in the direction of the first molded part preferably has an angular amount between 4 ° and 70 °. In particular, the membrane has a thickness of 4 mm or less, in particular 3 mm or less, in the clamping area. The membrane projection preferably has a height ratio to a membrane thickness of the membrane of 2.0 or less. According to initial tests, a height ratio of 0.1-1.0 offers particularly good support for the membrane. It is particularly advantageous if the membrane projection forms a circumferential sealing lip. In particular, such a press arrangement or press mold is designed for pressing the article from a ceramic material to be pressed.

Independently preferred is the use of such a press mold for pressing a pressed product in the form of a powder or granulate with an average grain diameter greater than a free distance between the opposing edge sections in the area of the ventilation gap.

According to the invention, an essentially burr-free pressing is made possible, the ventilation gap being selected to be so narrow over a large part of the circumference that no powder or granulate can enter which forms a burr on the edge of the article during demolding. This is made possible by the fact that a remaining pressing burr is consciously accepted in a relatively small circumferential section of the article, namely in the filling area of the granulate or powder to be pressed. In this area of a remaining press burr, the ventilation gap for forming the filling space is expediently wider than previously usual, which leads away from the previous idea of providing a circumferentially uniform ventilation gap, for which the membrane forms a filling pocket or a filling space with a correspondingly large distance from the opposite membrane . According to a further aspect, the outer edge region of the membrane is no longer angled by 90 ° or even twice by 90 °, but is formed with a projection that is axially parallel to the pressing direction and engages in a corresponding receiving opening of an opposing molded part. This is preferably not just one or more such projections, but rather an annular circumferential bead which protrudes from a side wall of the membrane. This enables both a material saving with regard to the membrane material in the membrane production and a simplified assembly on the corresponding molded part.

Fig. 1

eine Teilschnittansicht durch eine Pressenanordnung bzw. durch eine darin eingesetzte Pressenform zum Pressen von Pressgut zu einem Artikel;

Fig. 2

einen ersten Ausschnitt dieser Pressenform; und

Fig. 3

einen zweiten Ausschnitt dieser Pressenform.

An exemplary embodiment is explained in more detail below with reference to the drawing. Show it:

Fig. 1

a partial sectional view through a press arrangement or through a press mold inserted therein for pressing pressed material to form an article;

Fig. 2

a first section of this press mold; and

Fig. 3

a second section of this press mold.

Fig. 1 shows a first embodiment of a press arrangement or a press mold P inserted therein, with a representation that is not true to scale being selected for better illustration of essential aspects. Figs. 2 and 3 show two enlarged sections Fig. 1 .

The press mold P usually consists of a large number of other known individual components, in particular a first molded part 1 and a second molded part 2. In the assembled or closed position of the two molded parts 1, 2, an article space 3 is formed between them. In a closed position, pressing material 5 is filled into the article space 3 via a filling device 4. The material to be pressed 5 is then pressed into an article 6 in the article space 3. The article 6 is, for example, a plate or a bowl and the material to be pressed 5 in such a case is correspondingly a ceramic powder or granulate. In principle, other pressed goods 5 can also be pressed into articles 6 in such a press arrangement or press mold. The individual components of such a press arrangement or press mold can also be constructed and arranged in a manner known per se not only as described, but also in accordance with further embodiments.

The first molded part 1 and the second molded part 2 each have an edge section 10, 10 * and 20, 20 *. The two edge sections 10, 20 lie opposite one another in a closed position of the press mold and delimit the article space 3 in the lateral direction.

In the embodiment shown, the first molded part 1 consists of a rear main body 11 with a surface shaped on the front. The front, ie facing the article space 3, is on the rear Main body 11 an elastic membrane 12 pulled up. The elastic membrane 12 is firmly connected to the rear main body 11 in the area of its outer circumference outside the article space 3. A fixed connection is also to be understood in particular as being clamped or clamped in the edge region of the membrane 12, so that it rests freely against the adjacent surface of the main body 11 in the region between its edge. Optionally, the membrane 22 can of course be firmly cast onto the molded body 23 on one of the molded parts 2, as shown on the second molded part 2. This membrane 22 on the second molded part 2 could, however, only be fastened in a laterally clamped manner, like the membrane 12 on the first molded part 1.

In particular in the area of the article space 3, there is a pressure space 13 between the membrane 12 and the surface of the rear main body 11, which is connected to a pump via one or more pressure lines 14. Via the line 14, the space 13 for pressing a pressed material 5 filled into the article space 3 is filled with, in particular, a hydraulic medium at such a high pressure p that the membrane 12 presses against the pressed material 5. As a result, an isostatic compression of the pressed material 5 to form the article 6 is carried out in the article space 3.

In the embodiment shown, the first molded part 1 also has an outer circumferential body 15 in a manner known per se. The actual edge section 10 of the first molded part 1 is thus formed in this exemplary embodiment from a section of the membrane 12 on the side of the article space 3 and optionally from a side wall of an additional membrane fastening body 15.

The second molded part 2 also consists of a rear main body 21 and a front membrane or coating 22, ie facing the article space 3. While in the first molded part 1 the front wall of the main body 11 in conjunction with the membrane 12 is shaped to form a desired contour of the article 6, in the second molded part 2 a molded body 23 is inserted between the membrane or coating 22 and the main body 21, for example. In this embodiment, the edge section 20 is formed by a lateral section of the membrane or coating 22 and the end face of a narrow peripheral wall 24 of the main body 21 of the second molded part 2. The end face of the narrow circumferential wall 24 is located radially on the outside of the membrane 22 and the molded body 23 and projects axially parallel to the pressing direction or axis of movement X of the molded parts 1, 2. The filling device 5, which, according to a particularly preferred embodiment, is designed as part of a circumferential body 40 around the side wall of the rear main body 21 of the second molded part 2, is used to fill the article space 3. This circumferential body 40 preferably serves as a so-called filling ring and has a press material channel 41 in at least one section. The press material channel 41 leads from an outer peripheral wall to an inner wall of the circumferential body 40, which in a filling position is arranged adjacent to a widened section of the ventilation gap as filling space S * between the edge sections 10, 20. In the filling position, the pressed material 5 is filled into the article space 3 via the pressed material channel 41 and the filling space S *.

As an essential feature according to the invention, the edge sections 10, 10 *, 20, 20 * of the two molded parts 1, 2 are designed with different dimensions over their circumference.

Over most of the circumference, the ventilation gap S has a width or width of 0.25 mm or less, in particular 0.20 mm or less. With the usual grain sizes of the powder or granulate to be filled into the article space 3 as the pressed material 5, this distance between the two membranes 12, 22 ensures that no pressed material penetrates into the ventilation gap S. In the case of a particularly fine-grained material to be pressed 5, the distance between the membranes 12, 22 or the width of the ventilation gap S can optionally also be set smaller. Small proportions of the pressed material, in particular dust, can still penetrate into the ventilation gap S, but the amounts involved are so small that when the article 6 is pressed on its peripheral edge in the area of the ventilation gap S, no burr is formed. Any burrs that have formed are so small that they can be removed without special deburring steps by means of, for example, simple sponging.

In order to support the filling of the article space 3 with the material to be pressed 5, a negative pressure pu is applied on the outside of the ventilation gap S. To be able to clamp an outside clamping area 16 of the membrane 12 of the first molded part 1 between the first molded part 1 and / or a membrane fastening body 15 arranged on the outside on the one hand and on the other hand opposite a lateral peripheral area of the rear main body 21 of the second molded part or the encircling body 40 , the negative pressure pu is not discharged directly from the ventilation gap S in a straight outward direction. Instead, between the outer circumferential wall of the rear main body 21 of the second molded part 2 and an inner wall of the circumferential body 40, an annular gap S ° parallel to the axis of movement X of the molded parts 1, 2 with preferably also only a small opening width of 0.25 mm, in particular 0.20 mm or less. The annular gap S ° is in communication with the ventilation gap S, for which purpose the ventilation gap S is preferably from the transition to Article space 3 extends up to the annular gap S °. The annular gap S ° opens on its side facing away from the ventilation gap S into a ventilation channel 43, which can optionally have a greater width.

Depending on the embodiment, both the ventilation channel 43 and the annular gap S ° can extend only partially, optionally over several partial sections or over the entire circumference of the second molded part 2. Particularly preferably, the arrangement of the annular gap S ° and the ventilation channel 43 extends over the same circumferential area as the circumferential area over which the ventilation gap S extends. Via a vent line 42 leading to the outside, the vent channel 43, the annular gap S ° and the vent gap S, the negative pressure pu can thus advantageously be applied to the article space in order to achieve its ventilation while the article space 3 is being filled with the pressed material 5.

In order to still be able to fill the article space 3 with the material to be pressed 5, the filling device 4 is arranged in at least one circumferential section of the press arrangement. In particular, for filling, the press arrangement is arranged in such a way that the movement axis X runs horizontally and the filling device 4 is arranged on an upper side of the press arrangement in such an orientation. The filling device 4 essentially consists of a press material silo or a press material supply line which is connected to the product channel 41. In the case of a product channel 41 that is open towards the filling space S *, the filling device 4 preferably additionally has a closing element which, for example, can be adjusted in the form of a slide in the path of the product channel 41 in order to open it only to fill the article space 3.

Since the ventilation gap S for filling the article space 3 in such an arrangement must be able to be filled with closed molded parts 1, 2, between the edge sections 10 *, 20 * or between the membranes 12, 22 or coatings in the area of the edge sections 10 *, 20 * the filling space S * is formed with a sufficient distance between the opposing membranes 12, 22. A width of the filling space S * or a distance between the membranes 12, 22 of several millimeters, in particular of 1-3 mm, is particularly preferred.

In order to be able to design the filling space S * sufficiently wide, a membrane thickness of the membranes 12, 22 is correspondingly reduced in this area and / or a surface of the first molded part 11 located at the rear of the membranes 12, 22 is designed correspondingly deepened.

In the circumferential direction of the edge sections 10 *, 20 *, the filling space S * extends in particular over a width equal to or greater than an adjacent width of the filling material channel 41. In particular, an extension of the filling space S * in the circumferential direction of the edge sections 10 *, 20 * of 5% appears. as particularly cheap. However, filling spaces S * that are narrower or wider in the circumferential direction can also be provided as filling pockets. Wider filling pockets offer the advantage of faster filling of the article space 3 with the pressed material 5 *, while a filling space S * that is narrower in the circumferential direction offers the advantage of a pressing burr 6 * that is only narrower at the edge of the article 6 in the circumferential direction.

In order to reduce or prevent a mutual disturbance of the filling process of pressed material 5 through the filling space S * into the article space 3 on the one hand and the venting process by sucking air out of the article space, the filling space and the ventilation gap are through one of these Fluidically separating design of an area between these spaced apart. This can be implemented, for example, by a web running in the radial or outward direction. Depression structures of different depths relative to a base level of the surface of the membrane in the area of the edge section for forming contours of different depths for the filling space and the venting spar can also be implemented.

With such a configuration of a press arrangement or press mold, the ideal goal of a completely press burr-free article 6 is not achieved, but advantageously a press burr 6 * is limited to a relatively small peripheral area of the article 6, while the remaining peripheral area of the article 6 is or only free of press burrs still has negligible traces of a press burr.

According to a further aspect of the preferred press arrangement, the clamping area 16 of the elastic membrane 12 of the first molded part 11 has an advantageous configuration.

The clamping area 16 represents the outermost circumferential area of the membrane 12, which extends on the outside of the filling space S * or on the outside of the ventilation gap S. Instead of a clamping area 16 with two sections angled by 90 °, the clamping area 16 has, in particular, at least one membrane projection 17 which extends from the membrane 12 in a direction that is essentially axially parallel to the movement axis X. The membrane projection 17 is arranged in such a way that it engages in a correspondingly configured receiving opening for the membrane projection 17, the receiving opening being let into a wall of the first molded part 10 on which the Clamping area 16 of the membrane 12 rests. The membrane projection 17, embedded in the receiving opening, causes a lateral tensile resistance to prevent the membrane 12 from being drawn in in the direction of the article space 3. The membrane projection 17 is elastic and can therefore be dimensioned larger than the receiving opening that receives it.

To improve the hold of the membrane 12, it has two oppositely angled angular ranges with angles α, the angles α preferably being arranged in an angular range of 5 to 70 °. This avoids casting surfaces that are angled by 90 ° and standing vertically, which means that the membrane can be pivoted as required when the membrane is being cast. This significantly simplifies the casting of extremely difficult diaphragm contours.

Further advantages are offered by the fact that a uniform membrane thickness of the membrane 12 can be achieved with such an arrangement. As a result, the membrane 12 is easy to cast, with only a small amount of membrane material being required for casting the membrane. During the use of the mold for pressing articles 6, less flexing work also acts on the angular areas or the angled transitions in the clamping area 16 of the membrane 12, which significantly increases the service life of the membrane 12. Also because such a membrane 12 does not have any undercuts, it is particularly advantageous since it is easy to cast during the membrane production.

Such a membrane 12 preferably has a membrane thickness in the range of 0.5-3 mm, it being possible for the membrane thickness in particular to be of a largely uniform thickness over the entire surface of the membrane 12. The membrane projection 17, which is preferably designed as a completely or largely circumferential bead or sealing lip, preferably has a ratio of the height of the membrane projection 17 to the membrane thickness of 0.1-1.

Instead of a single membrane projection 17, a multiplicity of such membrane projections 17 with corresponding opposing receiving openings can also be arranged distributed over the circumference of the first molded part 10. In particular, the design as a completely circumferential or, except for the area next to the filling space S *, a circumferential annular membrane projection 17 can advantageously be implemented.

The membrane 12 is preferably manufactured from polyurethane, silicone or another flexible material. The fastening of the membrane 12 made of such a material can be done in a simple manner by clamping the clamping area 16 between the wall of the first molded part 10 and an opposite wall of the second molded part 2 and / or the circumferential body 40. As shown, the membrane 12 can preferably be fastened to the rear main body 11 of the first molded part 1 by being clamped by means of the membrane fastening body 15. This can enable the membrane 12 to be firmly attached directly to the first molded part 1, regardless of the current position of the opposite molded part 2 or of the circumferential body 40. With such an arrangement, the membrane projection 17 forming a sealing lip is pressed into the corresponding receiving opening or pressed against the adjacent surface of the rear main body 11, which results in a particularly good seal.

A support section between the article space 3 and the outermost section of the clamping area 16 ensures that the membrane 12 is not pulled inward during pressing. The support can be formed in a simple manner by a section of the rear main body 11 protruding in the pressing direction, to which the two angled sections of the clamping area 16 adjoin in the outside direction.

The first molded part 1, the second molded part 2 and / or the circumferential body 40 serving as a filler ring can be adjusted relative to one another in the direction of an axis of movement X. The movement axis X preferably runs centrally through the article space 3 and along its short height dimension. In other words, the movement axis X runs through the first molded part 1, transversely through the article space 3 and through the second molded part 2 perpendicular to an article plane spanned by the article space 3. The revolving body 40 can be adjustable along an axis parallel to this or the same as this central movement axis X. Preferably, however, as shown, the circumferential body 40 is firmly connected to the second molded part 2 or, if necessary, even constructed in one piece with the second molded part as a lateral widening of the latter.

An adjustment device is used for adjustment, which is provided and programmed via a central control device for moving the individual components of the adjustment device or for moving the first molded part 1, the second molded part 2 and / or the rotating body 40 separately. The arrangement is preferably selected such that only one component, the first or the second molded part 1, 2, is moved. In addition, the control device usually controls the pressing in or letting out of the hydraulic medium into the pressure space 13 between the membrane 12 and the rear main body 11 of the first molded part 1.

To adjust the mechanical elements, the adjusting device preferably has a plurality of piston-cylinder devices (not shown in the figure). A first piston-cylinder device is used to adjust the first molded part 1 along the axis of movement X. A second piston-cylinder device is used to adjust the second molded part 2 along the axis of movement X. The third The piston-cylinder device is used to adjust the rotating body 40.

In principle, other configurations of the adjustment device are also possible. For example, one of the molded parts can be arranged as a stationary component in the press arrangement. In addition, the circumferential body 40 can optionally be designed as a component of the press mold P or as an independent component of the press arrangement. In the case of the formation as an independent component, the rotating body 40 is then arranged together with the press mold in the press arrangement. Correspondingly, the piston-cylinder device for adjusting the rotating body 40 can be connected directly to, for example, a frame of the press arrangement. Alternatively, the piston-cylinder device for adjusting the circumferential body 40 can also be connected to the press mold P and / or to the first molded part 1 or a rear section of its main body 21.

In the illustrated embodiments, the circumferential body 40, which is arranged on the outside of the first molded part 1 and the ventilation gap S, thus preferably serves both as a filling device and as a ventilation device. However, a multi-part design can also be implemented, in which separate, independent components for venting or for filling are mounted on one another or on a common base. Alternatively, for example, a section of one of the edge sections or both of the edge sections 10, 20 can be widened in a circumferential area such that a gap S remains open as a filling gap when the edge sections 10, 20 are otherwise close to one another. In the case of a non-adjustable circumferential body 40, for example, in the area of the filling device 4, the closing element 45 can be adjusted to close or open the product channel. A described preferred embodiment of the clamping area 16 with angles of less than 80 °, in particular less than 71 °, of the membrane 12 can be can of course also be transferred to other membranes to be fastened in this way.

In a first process step for producing the article 6, the press arrangement or the press mold is closed. For closing, one or both of the molded parts 1, 2 and / or the circumferential body 40 serving as a filling ring are adjusted, depending on the embodiment. In the illustrated embodiment, only the first molded part 1 is to be adjusted in the direction of the second molded part 2 in order to almost close the ventilation gap S between the two adjacent edge sections 10, 20.

The two mold parts 1, 2 are moved so far towards each other that the gap as a ventilation gap S between the two edge sections 10, 20 of the two mold parts 1, 2 remains sufficiently open to ventilate the article space 3, but to accommodate parts of the pressed material 5 closed too far. At most, negligible portions, in particular dust portions, of the pressed material 5 can penetrate into the ventilation gap S. In particular, the ventilation gap S is closed to a free width or width of 2.5 mm or less, in particular of 2 mm or less.

In order to enable compensation for varying properties of the pressed material, in a subsequent process step the hydraulic medium is introduced or pressed in through the lines 14 into the space 13 between the membrane 12 and the rear main body 11 of the first molded part 1 so that the membrane 12 does The receiving volume of the article space 3 for the pressed material 5 to be filled is suitably reduced or, if necessary, enlarged.

If the circumferential body 40 should be designed as an independently adjustable component, this is adjusted in this method step into a filling position which the Transport of the pressed material 5 from the pressed material channel 41 via the filling space S * into the article space 3 is made possible.

In the case of a non-adjustable circumferential body 40 or in the case of an externally widened rear main body 21 instead of such a circumferential ring, the closing element 45 can be adjusted in the area of the filling device 4 to close or open the product channel. In particular, the filling device 4 can also be designed as an independent arrangement of components and can be arranged on a press arrangement adjacent to the filling space S *.

The filling with the pressed material 5 is preferably supported in that the negative pressure pu is applied to the ventilation gap S at other sections of the adjacent edge sections 10, 20 in order to suck air out of the article space 3 and to support the filling of the article space 3.

After filling the tool, the hydraulic medium is pressed in a subsequent process step through the lines 14 into the space 13 between the membrane 12 and the rear main body 11 of the first molded part 1, so that the membrane 12 presses the pressed material 5 located in the article space 3 and so the article 6 trains.

The pressed article 6 is finally gradually relaxed by diverting the hydraulic medium via the pressure lines 14 and / or spacing the molded parts 1, 2 apart from one another, as shown, and after opening the molded parts 1, 2 is discharged onto a conveyor belt. In the illustrated alignment of the press mold, the article 6 slides downward out of the press mold P onto a conveyor belt. Apart from an edge area, which was next to the filling space S * during pressing and which was one under certain circumstances even has a thick press burr, article 6 is ideally completely free of press burrs.

Claims (16)

1. Pressing arrangement having an isostatic press mould (P) for pressing material to be pressed (5) to form an article (6), having

   - a first mould part (1) having an edge portion (10),

   - a second mould part (2) having an edge portion (20),

   - an article space (3) which, in a closed position, is formed between the mould parts (1, 2) and their edge portions (10, 20),

   - an elastic diaphragm (12), which is fastened to the first mould part (1) over the surface thereof which faces towards the second mould part (2) by way of a clamping region (16) on the outer side of the diaphragm (12) outside of the article space (3),

   - a diaphragm (22), which is arranged on the second mould part (2) over the surface thereof which faces towards the first mould part (1),

   - an adjusting device for adjusting the first and/or the second mould part (1, 2) relative to one another into a position for the filling of the article space (3) with the material to be pressed (5) and for the pressing of the material to be pressed to form the article (6), and for adjusting the first and/or the second mould part (1, 2) relative to one another into a spaced-apart position for the removal of the pressed article (6), and

   - a control device for controlling the movement of the adjusting device,
   wherein

   - a filling space (S*) having a spacing between the first mould part (1) and the second mould part (2) that is sufficiently wide for introduction of a material to be pressed (5) leads into the article space (3) from outside of the first mould part (1) and the second mould part (2) through at least one peripheral portion of the edge portions (10*, 20*) of the first mould part (1) and of the second mould part (2),

   - a remaining peripheral region of the mutually opposite edge portions (10, 20) of the first mould part (1) and of the second mould part (2) has a ventilation gap (S) for ventilating the article space (3), characterized in that,

   - in the region of the filling space (S*), a diaphragm thickness of the diaphragms (12, 22) is reduced and/or a surface of the first mould part (1), said surface lying towards the rear of the diaphragm (12) which is fastened to the first mould part (1), is of recessed design.
2. Isostatic press mould (P) for pressing material to be pressed (5) to form an article (6) in a pressing arrangement, wherein the press mould has

   - a first mould part (1) having an edge portion (10),

   - a second mould part (2) having an edge portion (20),

   - an article space (3) which, in a closed position, is formed between the mould parts (1, 2) and their edge portions (10, 20),

   - an elastic diaphragm (12), which is fastened to the first mould part (1) over the surface thereof which faces towards the second mould part (2) by way of a clamping region (16) on the outer side of the diaphragm (12) outside of the article space (3),

   - a diaphragm (22), which is arranged on the second mould part (2) over the surface thereof which faces towards the first mould part (1), and

   - attachment regions for an adjusting device for adjusting the first and/or the second mould part (1, 2) relative to one another into a position for the filling of the article space (3) with the material to be pressed (5) and for the pressing of the material to be pressed to form the article (6), and for adjusting the first and/or the second mould part (1, 2) relative to one another into a spaced-apart position for the removal of the pressed article (6),
   wherein

   - a filling space (S*) having a spacing between the first mould part (1) and the second mould part (2) that is sufficiently wide for introduction of a material to be pressed (5) leads into the article space (3) from outside of the first mould part (1) and the second mould part (2) through at least one peripheral portion of the edge portions (10*, 20*) of the first mould part (1) and of the second mould part (2),

   - a remaining peripheral region of the mutually opposite edge portions (10, 20) of the first mould part (1) and of the second mould part (2) has a ventilation gap (S) for ventilating the article space (3), characterized in that,

   - in the region of the filling space (S*), a diaphragm thickness of the diaphragms (12, 22) is reduced and/or a surface of the first mould part (1), said surface lying towards the rear of the diaphragm (12) which is fastened to the first mould part (1), is of recessed design.
3. Pressing arrangement or press mould (P) according to a preceding claim, in which an annular gap (S°) which is parallel to a movement axis (X) of the mould parts (1, 2) forms between the outer peripheral wall of a rear-side main body (21) of the second mould part (2) and an inner wall of the encircling body (40), said annular gap being in communicative connection with the ventilation gap (S) and opening, on the side thereof which faces away from the ventilation gap (S), into a ventilation channel (43) to which a negative pressure (pu) can be applied.
4. Pressing arrangement or press mould (P) according to Claim 3, in which the ventilation gap (S) extends from the transition to the article space (3) up to the annular gap (S°).
5. Pressing arrangement or press mould (P) according to either of Claims 3 and 4, in which the annular gap (S°) has the same opening width as the ventilation gap (S).
6. Pressing arrangement or press mould (P) according to one of Claims 3 to 5, in which the arrangement composed of the annular gap (S°) and the ventilation channel (43) extends over the same peripheral region as the peripheral region over which the ventilation gap (S) extends.
7. Pressing arrangement or press mould (P) according to a preceding claim, in which the filling space (S*) in the at least one peripheral portion of the edge portions (10*, 20*) of the first mould part (1) and of the second mould part (2) extends over a peripheral portion of less than 31°, in particular less than 16°, preferably less than 8°, of the periphery of the peripheral portion.
8. Pressing arrangement or press mould (P) according to a preceding claim, in which the first and the second mould part (1, 2) are arranged relative to one another in a closed position, in particular in the same closed position, for the filling with the material to be pressed (5) and for the pressing of the material to be pressed (5) to form the article (6) .
9. Pressing arrangement according to a preceding claim, in which the control device is designed to set at least one of a receiving volume for the material to be pressed (5) and/or a width of the article space (3) between the first mould part (1) and the second mould part (2) by application of a correspondingly dimensioned pressure (p) in a pressure space (13) between a surface of the first mould part (1) and an elastic diaphragm (12) situated thereon which faces towards the second mould part (2) and which is fastened to the first mould part (1).
10. Isostatic press mould (P) according to a preceding claim for pressing material to be pressed (5) to form an article (6), having

    - a first mould part (1) having an edge portion (10),

    - a second mould part (2) having an edge portion (20),

    - an article space (3) which, in a closed position, is formed between the mould parts (1, 2) and their edge portions (10, 20), and

    - at least one elastic diaphragm (12), which is fastened to the first mould part (1) over the surface thereof which faces towards the second mould part (2) by way of a clamping region (16) on the outer side of the diaphragm (12) outside of the article space (3),
    wherein

    - the clamping region (16) of the diaphragm (12) is fixedly clamped against the surface of the first mould part (1) or against a component fastened thereto,
    wherein

    - the clamping region (16) of the diaphragm (12) has at least one diaphragm protrusion (17) which is pushed into a receiving opening in the surface of the first mould part (1), and

    - the clamping region (16), in the direction of an article plane, said direction being on the outside as seen from the article space (3), has at least one deflection of the diaphragm (12) by less than 80° in the direction of the first mould part (1).
11. Press mould according to Claim 10, in which the deflection of the diaphragm (12) in the direction of the first mould part (1) has an angular value of between 4° and 70°.
12. Press mould according to either of Claims 10 and 11, in which the diaphragm (12) has a thickness of 4 mm or less, in particular of 3 mm or less, in the clamping region (16).
13. Press mould according to one of Claims 10 to 12, in which the diaphragm protrusion (17) has a height ratio to a diaphragm thickness of the diaphragm (12) of 2.0 or less, in particular of 0.1 - 1.0.
14. Press mould according to one of Claims 10 to 13, in which the diaphragm protrusion (17) forms an encircling sealing lip.
15. Pressing arrangement or press mould according to a preceding claim, which is configured to press the article (6) from a ceramic material to be pressed (5) .
16. Use of a pressing arrangement or press mould according to a preceding claim for pressing a material to be pressed (5) in the form of a powder or granulate having a mean particle diameter greater than a free spacing between the mutually opposite edge portions in the region of the ventilation gap (S) .

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