EP3075504B2 - Device for making concrete moulds in a moulding machine - Google Patents

Description

The invention relates to a device for the production of concrete molded parts in a molding machine.

Devices for manufacturing concrete components, such as paving stones, are typically used for automated production and comprise a molding machine with a punching unit and a mold base into which the punching unit engages. The mold base usually has one or more cavities open at the top and bottom. The mold base is placed on a horizontal surface with a lower boundary plane of a stone field, which closes the lower openings of the mold. The cavities are filled with concrete mix through the upper openings and then pressed against pressure plates located on the punching unit. These pressure plates are lowered into the cavities through the upper openings. Subsequently, the concrete mix is compacted by vibration, typically against the base, to form dimensionally stable concrete components. These are then demolded through the lower openings of the cavities.

The punch unit is connected to a typically hydraulically actuated vertical movement unit of the molding machine and can be moved vertically by means of this unit. In conventional designs, this connection can be achieved via a ballast unit, which usually forms a mold top section with the punch unit as a single, easily handled assembly. A stop on the punch unit's rams ensures a uniform block height even with varying compaction of the concrete mix.

In known molding machines, the connection between the upper and lower mold parts is of particular importance. For example, it is evident from the DE 36 38 207 A1 It is known that with such molds, if the upper mold part is not properly aligned with the lower mold part, there is a risk of the pressure die colliding with the top surface of the lower mold part. This occurs particularly when the upper mold part is inserted into the lower mold part in the molding machine to form and compact the concrete part to be produced. According to solutions known in the art, this problem has been avoided by precisely aligning the upper mold part with the lower mold part and by providing corresponding ramps on the mold cavities to facilitate the insertion of the pressure plates.

However, the connection between the upper and lower mold parts has already been examined in more detail in the prior art in another context. For example, it has been shown that... DE 199 24 926 A1 A stone forming machine is known in which a weighable stone mold is arranged on the guide columns. The stone mold consists of a lower mold part and an upper mold part, which are arranged either rigidly connected to each other or slidably relative to each other along the working section. This allows for easy further processing, in particular by means of a separating mechanism that separates the lower mold part and the upper mold part.

From the DE 10 2005 048 930 A1 A stone mold for the production of concrete blocks is known, comprising a mold upper part with at least one punch with a pressure piece and a mold lower part with at least one mold cavity for use in a stone molding machine, wherein the mold lower part is movable up and down in a stone molding machine. The mold lower part can be placed on a mold base of the stone molding machine, and the mold upper part can be coupled to a machine mount of the stone molding machine that is movable up and down. A filling box of the stone molding machine is movable over the mold lower part, and the mold upper part and/or the mold lower part has clearance relative to a machine frame of the stone molding machine. A centering device is provided for aligning the mold lower part and the mold upper part in an xy-plane. This ensures precise centering of the two mold parts relative to each other, whereby a conical section on the centering device slowly releases the centering of the mold parts after the pressure piece has entered the mold cavity.

A very similar approach to the latter text is described in the US 2006/197259 A shown, which discloses the features of the preamble of claim 1. Here too, an initial positive guidance is described by means of a centering device when the pressure piece is immersed, which is then released upon further immersion.

In the DE 10 2004 004 188 A1 A concrete formwork block manufacturing device is shown, which has guide devices that facilitate the alignment of the pressure plates in the mold cavities. For this purpose, complementary and mutually communicating guide elements for relative movements between these two components, namely the upper and lower mold parts, are provided on the upper and lower mold parts, respectively, outside the pressure pieces and associated mold cavities.

The object of the invention is to create a device for the production of concrete mold parts in a molding machine in which the centering between the upper mold part and the lower mold part is further improved in order to prevent, in particular, damage to pressure plates in the event of possible contact with side walls of the mold cavity.

This problem is solved by the features of claim 1. Further advantageous embodiments of the invention are the subject of the dependent claims. These can be combined with one another in a technologically meaningful manner. The description, particularly in conjunction with the drawing, further characterizes and specifies the invention.

According to the invention, a device for producing concrete molded parts in a molding machine is created, comprising a mold upper part with at least one pressure ram for transmitting a force to at least one pressure plate, wherein the pressure plate can be inserted vertically into an opening of a mold cavity in a mold lower part, wherein the mold lower part is surrounded by a frame having a guide means connected to the mold upper part, which is designed such that the mold lower part can be tilted relative to the mold upper part from the vertical direction during the engagement of the pressure plates in the openings of the mold cavity.

According to the invention, the lower mold part is therefore not connected to the upper mold part by a guide that would merely fix the relative positions between the two. It has surprisingly been found that a guide that allows the upper mold part to tilt from the vertical direction provides greater stability and a longer service life for the printing plates attached to the die, since fine structures, such as indentations or chamfers on the printing plates, exhibit less wear. The solution according to the invention thus does not focus on the correct and centric installation of the lower mold part relative to the upper mold part to prevent a printing plate from contacting an opening in the mold, but rather allows the impact of any contact to be minimized by providing an additional degree of freedom in the movement of the printing plates. Furthermore, guiding the lower mold part in the guide creates a starting position for its position relative to the upper mold part, which can result in the printing plates being inserted without impact. However, instead of specifying the exact relative positioning, which is also rigidly predetermined in previous systems known from the prior art, the invention allows a kind of self-adjustment, so that previously unattainable service lives can be achieved through the possibility of tilting and, if necessary, rotating.

According to one embodiment of the invention, the guide means is arranged on two opposite sides of the frame.

Accordingly, it is possible to divide the guide element into individual components, whereby it is considered sufficient to equip only two opposite sides of the frame with parts of the guide element. For example, in the case of a rectangular mold cavity, a part of the guide element can be arranged on each of the two shorter sides of the mold cavity, opposite each other in the area of a corner of the mold cavity. Such a design allows the lower mold part to tilt relative to the upper mold part while still enabling the establishment of a defined starting position.

According to the invention, the guide means comprises an elongated body formed along the vertical direction with side lines that are at least partially parallel to the vertical direction, and which engages in a passage that corresponds at least partially.

The guide element can be easily formed by an elongated body guided through a corresponding opening. One possibility is that the elongated body has an outer surface that is parallel to an inner dimension of the opening over its entire length. However, it is also possible that at least individual sections of the elongated body or parts of the opening are designed as recesses with surfaces located further inwards, so that these cannot come into contact with the corresponding part. Such designs are not excluded within the scope of the invention. To enable the tilting of the lower mold part relative to the upper mold part according to the invention, it is merely provided that there is a clearance between the outer circumference of the elongated body and the inner circumference of the opening that limits the tilting.

According to the invention, the elongated body is connected to the upper part of the mold and the feedthrough is connected to the lower part of the mold.

A particularly simple implementation of the guide element involves arranging the guide in the lower mold part and providing the upper mold part with the elongated body. This allows the existing design of a lower mold part, commonly used in molding machines, to be retained; only a corresponding guide is required.

According to the invention, the elongated body and the feedthrough have dimensions that are chosen such that a maximum value of the tilting of the lower part of the mold relative to the upper part of the mold is specified.

To limit the tilting of the mold base against the mold base, i.e., to define a maximum tilting value, it is specifically provided that the elongated body and the guide, based on their dimensions, perform a corresponding movement limitation. Therefore, it is not necessary to provide additional components to limit the tilting, which further simplifies the manufacture of the device according to the invention.

According to the invention, the lower part of the mold can be tilted relative to the upper part of the mold by an angle which is in the range of less than 2° and in particular is approximately 1°.

To achieve the aforementioned improvement in the service life of printing plates when used in forming machines, it is not necessary to compensate for the tilting between the lower and upper parts of the mold via a to allow a large range. Rather, values of less than 2° already show a sufficient improvement compared to the forced centering typically provided for in the prior art. In individual cases, the values for the tilting, which are limited, for example, by the external dimensions of the elongated body and the feedthrough, can also be determined experimentally.

According to the invention, the elongated body is designed as a circular cylindrical pin which engages as a through-hole in a bushing arranged on the frame and provided with a circular cylindrical inner surface.

The pin can, for example, be made of hardened steel, so that when the lower part of the mold tilts to the upper part of the mold, the also hardened bushing allows a relative movement from the lower part of the mold to the upper part of the mold, but low wear values occur, so that the device according to the invention is not limited in terms of its service life by material stress in the guide means.

According to the invention, the outer diameter of the circular cylindrical pin is selected depending on the height of the bushing along the vertical direction and the inner diameter of the bushing arranged in the frame.

To determine the maximum possible tilt, both the outer diameter of the pin and the inner diameter of the frame must be considered, along with the axial height of the bushing. Based on these dimensions, the possible tilt can then be determined.

According to a further embodiment of the invention, the guide pin and/or the bushing are interchangeably attached in the guide means.

Due to the movement between the guide pin and the bushing, which also occurs in particular during the compaction process using a vibrator common in molding machines, it may be advantageous in certain applications to make these components replaceable in order to have a quick and easy way to replace them in case of wear.

According to a further embodiment of the invention, the guide means can be screwed onto the frame of the lower mold part laterally outside the mold cavity and outside the pressure dies laterally of the upper mold part.

The invention can also be extended to existing forming machines according to this embodiment by subsequently attaching the components of the guide means, for example, to the frame of the lower part of the mold and to the upper part of the mold outside the dies.

Fig. 1

eine Vorrichtung zur Herstellung von Betonformteilen gemäß einer Ausführungsform der Erfindung in einer Seitenansicht,

Fig. 2

die Vorrichtung aus Fig. 1 in einer gekippten Position in einer Seitenansicht,

Fig. 3

die Vorrichtung aus Fig. 1 in einer weiteren Seitenansicht,

Fig. 4

die Vorrichtung aus Fig. 1 in einer Seitenansicht aus einer in Vergleich zu Fig. 3 gegenüber liegender Richtung,

Fig. 5

schematische Bestandteile der Vorrichtung aus Fig. 1, und

Fig. 6

ein Detail der Vorrichtung aus Fig. 5 in einer schematischen Ansicht.

Some exemplary implementations are explained in more detail below with reference to the drawings. They show:

Fig. 1

a device for the production of concrete molded parts according to an embodiment of the invention in a side view,

Fig. 2

the device Fig. 1 in a tilted position in a side view,

Fig. 3

the device Fig. 1 in another side view,

Fig. 4

the device Fig. 1 in a side view from a comparison to Fig. 3 opposite direction

Fig. 5

schematic components of the device Fig. 1 , and

Fig. 6

a detail of the device Fig. 5 in a schematic view.

In the figures, identical or functionally equivalent components are marked with the same reference symbols.

In Fig. 1 A device VO is shown, suitable for producing concrete molded parts in a molding machine. The device VO has an interchangeable mold, formed by a lower mold part FU and an upper mold part FB. The lower mold part FU has a mold cavity, as is customary in the industry, with a suitably selected number of openings, so that concrete molded parts of the desired quantity and/or size can be produced with the device VO.

The upper mold section FB has a plurality of pressure plates DP, each pressure plate DP corresponding to an opening in the lower mold section FU. The pressure plates DP are each connected to a punch plate ST via a pressure die DS.

Above the stamping plate ST, a ballast device AE is provided, which, via the pressure stamps DS, can compress a concrete mixture introduced as filling material into the openings of the mold cavity in the mold base FU. The ballast element AE has fastening elements on its upper side which, together with other elements (not part of the present invention), enable the ballast element AE to be mounted in a molding machine.

The mold base is typically provided with a multitude of openings, the openings forming the mold cavity being surrounded by a frame RA. A guide FM is arranged between the frame RA of the mold base FU and the mold upper FO, ensuring alignment of the mold base FU relative to the mold upper FO.

The FM control system can be divided into individual units, which, as in Fig. 1 shown, for example, arranged on two opposite sides of the usually rectangular frame RA To clarify the function of the guide element FM, the plane spanned by the pressure plates DP is referred to below as the xy-plane. Perpendicular to this, i.e., along the pressure dies DS, lies the z-direction. The guide element FM is designed such that the lower mold part FU can tilt slightly relative to the upper mold part FB. Tilting here refers to a deviation from the xy-plane, such that when the pressure plates DP enter the mold cavities of the lower mold part FU, previously parallel sections of the upper mold part FB and the lower mold part FU will, in the event of tilting, form an angle with each other. This tilting can occur not only along the x-direction or the y-direction, as it is specifically intended that tilting in both directions should also be possible.

A correspondingly tilted arrangement of the device VO is in Fig. 2 As shown, it can be seen that the stops AS, which normally limit the immersion of the pressure plates DP into the mold cavities of the mold base FU when the mold is fully filled, do not simultaneously rest on the frame RA or on the mold base FU. It should be noted that the in Fig. 2 The chosen representation is greatly exaggerated, as the angle formed between the tilted and the parallel state is in the range of approximately 1°.

In Fig. 3 The device VO is shown again in a side view. It can be seen that the guide FM does not have to be positioned centrally on the frame RA of the lower mold part FU or the upper mold part FB. Furthermore, Fig. 3 It can be seen that the guide element FM has a lower section into which a cylindrical guide pin FS can insert. The lower section is designed as a bushing, with the guide pin FS having a certain amount of play within the bushing, which has a cylindrical inner surface. The guide pin FS is attached to the upper mold part FB by means of a bracket HA, and the lower section of the guide element FM can be screwed to the lower mold part FU. This procedure allows for easy retrofitting of existing devices VO.

In Fig. 4 is the side view off Fig. 3 The diagram is shown again from the opposite side. The mounting of the guide element FM is identical to that on the opposite side, although other configurations are also conceivable. Furthermore, a fastening screw BF is shown, which holds the guide pin FS of the guide element FM. Therefore, it is possible, for example, to replace one or more guide pins FS after prolonged operation of the device VO.

In Fig. 5 The tilting of the lower mold part FU relative to the upper mold part FB is shown again in a schematic view. This schematic representation shows two guide pins FS, which, as already mentioned in connection with the Figs. 1 to 4 described, outside the printing stamps DS are attached to the upper part of the mold FB. The lower part of the mold, which is in Fig. 5 The lower support UA, as already mentioned, can accommodate the guide pins FS outside the frame RA. Due to the chosen dimensions within the lower support UA, it is possible for the lower mold part FU to tilt relative to the upper mold part FB, which is shown in Fig. 5 This is schematically illustrated using the angle WN. The angle WN is less than 2°, with a value of approximately 1° proving particularly advantageous. Since the limitation of the angle WN is advantageously achieved by dimensioning the guide pin FS within the passage inside the lower support UA, this is shown in Fig. 5 Marked as Detail A, shown again enlarged.

In Fig. 6 Detail A is shown in a sectional view, where a bushing BU is indicated within the lower support UA. The cylindrical inner surface of the bushing BU defines the cylindrical outer surface of the guide pin FS. The inner diameter of the bushing BU and the outer diameter of the guide pin FS can be easily calculated if the height of the bushing BU and the distance between the two guide pins FS are known. For example, to achieve a tilt of less than 1° with a distance of approximately 1.5 m between the two guide pins FS, the guide pin with an outer diameter of 40 mm can engage a 14 mm high bushing BU. The inner diameter of the bushing BU is chosen to be approximately 10% larger than the outer diameter of the guide pin FS to achieve the desired tilt of less than 1° of angle WN.

Claims (4)

1. Device for producing concrete moldings in a molding machine, which comprises an upper mold part (FB) having at least one pressure stamp (DS) for transmitting a force to at least one pressure plate (DP), and a lower mold part (FU) having a mold cavity that has at least one opening, it being possible for the pressure plate (DP) to be introduced in the vertical direction into the opening in the mold cavity in the lower mold part (FU), the lower mold part (FU) being surrounded by a frame (RA) which has a guide means (FM) that is connected to the upper mold part (FB) and comprises an elongate body which is formed in the vertical direction, is designed as a circular-cylindrical pin (FS), is connected to the upper mold part (FB) and has side lines which are at least partially parallel to the vertical direction, which body engages in an at least partially corresponding feed-through, which is a bushing (BU) that is arranged on the frame (RA) and is provided with a circular-cylindrical inner surface, and is designed such that the lower mold part (FU) can tilt relative to the upper mold part (FB) from the vertical direction during the engagement of the pressure plates (DP) into the openings in the mold cavity, characterized in that the elongate body and the feed-through have dimensions which are selected such that a maximum value of the tilt of the lower mold part (FU) relative to the upper mold part (FB) is specified, and that the outer diameter of the circular-cylindrical pin (FS) is selected on the basis of a height of the bushing (BU) in the vertical direction and an inner diameter of the bushing (BU) arranged on the frame (RA), wherein the lower mold part (FU) can be tilted relative to the upper mold part (FB) by an angle (WN) which is less than 2° and, in particular, is approximately 1°.
2. Device according to claim 1, wherein the guide means (FM) is arranged on two opposite sides of the frame (RA).
3. Device according to one of claims 1 to 2, in which the guide pin (FS) and/or the bushing (BU) are interchangeably secured in the guide means (FM).
4. Device according to one of claims 1 to 3, in which the guide means (FM) can be bolted to the frame (RA) of the lower mold part (FU) laterally outside the mold cavity and outside the pressure stamps (DS) laterally to the upper mold part (FB).