EP0767034B1 - Mould for making concrete elements - Google Patents

Abstract

The former has an upper plate (1) with multiple stamps each compacting concrete in a form in the lower former plate. Each stamp or the pressure plate (5) at its lowest part which comes into contact with the concrete can move vertically between stops relative to the upper former plate. The stamps are moved downwards under the same pressure. The stamps compact the concrete in each former to the same density by moving down an amount to suit the level of filling of each former before withdrawing under switch control. A second filling takes place and the stamps are re-lowered to compact the more uniformly filled formers to equal levels.

Description

The invention relates to a mold for machine production of concrete moldings with a mold base with at least a mold chamber and a mold top with one Load plate and as many stamps as mold chambers available.

The filling of the lower mold parts of such molds in the Manufacturing machine is carried out with a so-called filling car. This is a flat funnel that contains the molding material and back and forth directly over the upper edges of the molding chambers is moved. The material falls into the chambers and gets flush on the way back from the edge of the filling truck stripped. Now the distribution of the is only limited free-flowing concrete mass in the filling truck mostly different and depending on the position of the individual chambers within the mold or depending on the size of the mold chamber base necessarily different crossing times for the sinking of the molding material into the chambers To be available. The even filling of the mold chambers is therefore problematic.

But are the individual mold chambers with different Filled quantities or in the case of a large area Mold chamber the concrete filling is distributed unevenly, so there are shaped bodies of at least locally different density and / or height, depending on, in what dimensions the upper part of the mold is when compacted Maintains parallelism with the forming table. With extensive Despite constructive efforts, this cannot form can always be guaranteed to the desired extent.

Although it is already known from DE 24 06 688 A1, the stamp from multi-chamber molds with individual hydraulic cylinders press that acted on by the same pressure source are to face an uneven filling of the form to compress at least evenly and thereby Differences in strength of the individual moldings avoid. However, this is done with a trade-off different heights, but with some products is no longer a disadvantage.

US-A-3,222,748 is a stone making machine become known, which includes a form as a tool, the one rigid upper part with stamp and a lower part with Mold chamber includes. The top part has a Fastening plate on which the stamp for manufacturing the shape of the stones is attached. A The height of the stamp is adjustable within the shape not provided.

From document EP 0 211 449 B1 is a form according to Genus of claim 1 become known as a tool for use in a stone making machine. It is the stamp within the upper part of the mold in the height direction movably guided against stops, being an elastic Support is provided.

The invention has for its object a form to indicate with which it remains unchanged filling technology is possible to use concrete bodies with a highly uniform density, uniform height and surface structure manufacture. On the one hand, there are concrete moldings Concrete paving stones in the foreground, including multi-chamber shapes be used, and on the other hand large-volume concrete blocks and especially large and relatively thin plates that in Single or double molds can be produced.

Starting from a form of the type described in the introduction this task according to the invention by the characterizing Features of claim 1 solved. It will be a Molded top proposed, its in contact with the concrete coming lower stamp parts (printing plates) in one Stops define the stroke range with regard to the upper part of the mold are guided movably in the height direction, these Mobility or oscillation ability optionally changeable is. For this purpose, the lower stamp parts are below the effect of a pressure medium pressed down. Depending on Setting the pressure are the stamp or is the stamp yielding. If the pressure is reduced or completely removed so that the movable stamp parts on their top stops come to rest, so they turn inevitably at the same height or parallel to the forming table on.

The basic idea is a two-stage Conduct compression processes in such a way that first with compliant stamps (under air pressure) is pre-compressed and after refilling the created with different depth chamber cavities located at the same height and parallel to the molding table Post-stamping or a post-parallel stamp becomes. The parallelism to the form table comes about as soon as the air pressure is so far lowered that the pressure plate of the Stamp overcoming the force of a pressure medium chamber comes to rest with a movable wall at the stops. at this densification comes down very precisely to the Setting the reduced air pressure on. It will in particular suggested that to take full advantage of the subsequently described impact of air pressure is further reduced during the post-compression phase. The Lowering can happen continuously. The Air pressure before the end of the compression process or reach the value 0 at the end.

Through an important impact effect that occurs here the compression favors particularly. Because it is possible to achieve by sensitive adjustment of the air pressure, that the pressure plates don't just stick to their stops place, but dance on this, d. H. again and again bounce. This enables large concrete slabs of e.g. B. 70 x 90 cm and larger with a crack-free, flawless produce uniformly smooth surface, which so far especially not possible with relatively thin plates was. Another big advantage of the vibration ability of the Printing plates of the stamp or the resulting Impact is that the concrete slabs are not on the Printing plates "stick", but stand out easily from them to solve.

In the pre-compression process, each stamp essentially works the same force. From this even compression result in the different presupposed here Filling the chambers semi-finished moldings from clearly of different heights. So with the second filling where a lot of material is missing, a lot of refilled, where this refill due to the relatively small Refill a complete fill of the existing ones Creates voids. Overall, the sums are over the first and second filling quantities per chamber are almost the same, see above that shaped bodies arise, the height of which is practical Accuracy requirements of e.g. B. 1 mm corresponds best and the same density and therefore the same strength to have.

The use of such a form is not based on two filling and Compaction processes limited. In special cases also three or more processes take place, whereby to the Pre-compression pressurized the fluid and only during the last compression the pressure is reduced or completely is taken away.

For constructive training of pneumatic lifting devices for the movable stamp parts it is proposed that at a multi-chamber shape on each stamp one by one common compressed air source acted on the effective lower stamp part effective pressure medium chamber is provided with a movable wall. This, e.g. B. membrane or bellows, can be used with a stamp that has a shaft and the lower end of which has a movable pressure plate, in be arranged near the pressure plate. On the other hand, it is also possible, the individual pressure medium chambers approximately in height arrange the common load plate and their compressive forces via a movable stamp shaft or via special ones Transfer ram to the pressure plates, taking the ram in this case push through the tubular stamp shafts.

A preferred development of the invention is how mentioned, assume that the pressure medium chamber at the bottom Stamp arranged near the movable pressure plate is. It is suggested that on each stamp between a footplate firmly connected to the stamp shaft and an insert is arranged on the pressure plate, which is an upper part with an upper plate and one opposite this lower part guided in height with a lower plate has, the upper plate with the base plate and the lower plate is screwed to the pressure plate. The Insert also contains at least one with compressed air acted upon bellows and the stops to limit the Stroke range of the two parts of the insert. Such a Use has the advantage that the loads are firmly attached to the Stamping foot plates fastened and fastened can be easily converted so that the pressure plates in Movement of the invention and in terms of their Vibration behavior are controllable. With appropriate The screw holes can be dimensioned in the Stamp foot plates and the pressure plates when retrofitting be used.

For the mutual height control of the two parts of one Use on these are preferably interlocking Guide mandrels and sleeves arranged. As attacks on Limitation of the stroke of the pressure plates are at one spacers are attached to the two plates of the insert, which can also be designed as strips. As attacks to limit the stroke of the pressure plates downwards double-T-shaped on one of the panels of the insert Stop pieces can be attached in double T-shaped Cutouts from attached to the other plate Intervene spacers. To simplify production also be provided that a on the lower plate of the The other plate using the attached bolt interspersed and a widened head above the plate and has a support shoulder below this plate.

Fig. 1

einen Teilschnitt eines mit Druckluft beaufschlagbaren, beweglichen Stempels,

Fig. 2

einen Schnitt eines anderen Stempels, bei dem nur die Druckplatte beweglich und mit Druckluft beaufschlagbar ist,

Fig. 3

eine Seitenansicht, teilweise im Schnitt, eines eingebauten Einsatzes,

Fig. 4

eine Draufsicht der Stempelfußplatte und des Einsatzes entsprechend der Schnittlinie IV-IV,

Fig. 5

eine Ansicht einer der beiden in Querrichtung verlaufenden Distanzleisten des Einsatzes und

Fig. 6

eine Seitenansicht, teilweise im Schnitt, von Bruchstücken eines weiteren Einsatzes ohne Federn.

Embodiments of the invention are explained below with reference to the drawing. In detail shows

Fig. 1

a partial section of a movable plunger which can be pressurized with compressed air,

Fig. 2

a section of another stamp, in which only the pressure plate is movable and can be acted upon by compressed air,

Fig. 3

a side view, partially in section, of an installed insert,

Fig. 4

a plan view of the stamp foot plate and the insert according to section line IV-IV,

Fig. 5

a view of one of the two transverse spacer bars of the insert and

Fig. 6

a side view, partly in section, of fragments of another insert without springs.

1 must be viewed as a section of a Imagine the upper part of the mold, the one bearing several punches Load plate 1 is also included. The stamp shown is guided vertically, the stroke in the example is about 10 mm. The stamp consists of a Stamp shaft 2 made of square tube, a head plate 3, one Base plate 4 and a pressure plate 5 screwed to it, their edge formation with a downward-facing cutting edge the chamfer of the to be finished with this shape Concrete paving stone forms. The head plate 3 of the stamp is guided in a membrane receiving part 6, which together with a retaining ring 7 by means of screws 8 on the load plate 1 is screwed on. The stroke of the head plate 3 and thus the whole stamp is above by a stop surface 9 and limited below by the retaining ring 7. Spring screws 10 pass through the load plate 1 and the membrane receiving part 6 slidably with their upper cylindrical Shaft sections and are with the lower shaft sections screwed into the head plate 3. Between the heads of the Spring screws 10 and the load plate 1 are compression springs 11 clamped, the top plate 3 when the membrane is relaxed pull up to the stop surface 9.

On a central thin plate section of the Membrane receiving part 6 is a membrane 12 from below hung up and between this section and one Fastening ring 13 tightly clamped. The latter is with Screws 14 screwed on. The membrane 12 can on the Put head plate 3 and this against the force of Press the compression springs 11 down as far as they will go if through a line 15 which by means of a Diaphragm receiving part 6 through screw 16 is connected to compressed air through the membrane 12 completed interior penetrates. Line 15 is on a distributor 17 connected, which in turn via a Three-way valve 18 to a compressed air supply line 19 relevant stone making machine is connected.

On all membranes 12 and stamps of the concerned Mold upper part of a multi-chambered form is thus, if that Three-way valve 18 the connection between the Compressed air supply line 19 and the distributor 17 opens, the same air pressure. If the three-way valve 18 changed over, all membrane chambers are vented.

The working process with such a form proceeds like follows: First, the form is "filled" with concrete as usual. Since this is relatively dry and therefore limited free flowing is assumed, however, that given of the systematic difficulties just described an uneven filling level can be achieved, i.e. two here, for example, mold chambers in concrete contain different amounts.

After this first filling process is compressed (so-called "Preparting"). The stamps are under air pressure and are against the force of the springs 11 in their lower position. Under the effect of such machines always used vibrator and the pressure of the stamp the concrete masses compact in the molding chambers, whereby due to the resilience of the stamp the surface of the compacted concrete masses in those mold chambers that were more filled, higher than the less filled chambers.

Due to the subsequent refill, which is considerable includes smaller quantities, all chambers are filled again and smeared flush. The refill volume is however at the previously less filled chambers larger. Thus one occurs Equalization of the total in the individual chambers filled concrete volumes, so that in the now following Post-compression process, in which the pressure chambers over the Membranes 12 are vented, an approximately the same Production height for all made with this mold Concrete paving stones is reached. As usual, the Refilling so-called facing concrete used that the sight and Wear surface of the paving stone forms.

The three-way valve 18 could of course with one or two pressure reducing valves can be added to it allow for the different compression phases set appropriately different pressures.

In the embodiment of FIG. 2 are on one Load plate 1 'attached stiffening rails 20 shown. In contrast to FIG. 1, the stamp shaft 2 'is firmly attached here the load plate 1 'welded and carries a thin bottom Base plate 4 '. At this base plate 4 'with the help of Screws 21 screwed a membrane receiving part 6 ', wherein the screws also the fastening ring of the Hold membrane 12. Instead of the head plate 3 according to FIG. 1 here the pressure plate 5 'hung on spring screws 10. On the membrane 13 is in direct contact with it. A the hub of the Pressure plate 5 'bridging sealing ring 22 prevents this Penetration of concrete slurry into the space between the Pressure plate and the diaphragm receiving part. Here too are individual pressure rooms via lines 15 'with a Distributor 17 'connected, the internal pressure as in first example can be controlled.

In the embodiment according to Figures 3 to 5 are all components according to the invention in one insert 23 summarized. This is a retrofit component between the Base plate 4 '' and the pressure plate 5 '' of a stamp inserted, the four stamp shafts 2 '' as in the Examples described on a load plate 1 '' are attached.

The insert 23 comprises two mutually movable Assemblies by an upper plate 24 or a lower Plate 25 are characterized. On the top plate 24 a guide sleeve 26 under each punch shaft 2 ″ attached with a guide pin 27 on the lower Plate interacts. On the lower plate 25 are also four spacer strips 28 to joined together to form a square 31 attached. 3 shows a longitudinal bar 28 and Fig. 5 in a single representation a cross bar 30. Die Longitudinal strips each have two double-T-shaped cutouts 32 on with double-T-shaped stop pieces 33 interact. The latter are on the upper plate 24 with each two screws 34 firmly connected.

At the four corners and in the middle of the four sides bolts 35 are provided which have multiple functions to have. Since they all plates and the spacers in in the vertical direction, they initially appear next to the guide sleeves 26 and guide pin 27 as Management bodies with. Then connect the pressure plate 5 '' with the lower plate 25. You are in the pressure plate 5 ''. screwed in and a nut 36 tensions the lower two Plates together. To make room for the nuts 36 have the spacer strips 28 to 31 under their bores 37 for the screw bolts 35 rectangular edge recesses 38 on. And finally, the bolts 35 are used Support of compression springs 39, which the lower assembly of the Cushion insert 23 as it moves down. The Compression springs 39 are interposed between discs the base plate 4 '' and the respective head of the bolts 35 clamped.

To exert a pneumatic pressure force on the lower one Part of the insert 23 and the attached Pressure plate 5 '' contains a bellows 40 made of rubber or the like, which by means of two connecting plates 41 the lower plate 25 and the upper plate 24 screwed is. The connection screw connection of the bellows protrudes through the top corresponding recesses in the upper plate 24 and 4 '' footplate. The indicated compressed air hose 42 for the Bellows is between the punch shafts 2 '' upwards guided.

It remains to be noted that the upper plate 24 with the Base plate 4 '' is connected by short screws 43. In total, as shown in FIG. 4, there are eight such screws 43 intended. Some of them can be used before retrofitting 23 insert screw holes used become.

The mode of operation corresponds to that of the above Embodiments. Slack when not under pressure Bellows 40 are due to the spring action of the spacers 28 to 31 on the upper plate 24. 3 shows the Position with pressurized bellows 40. Its strength overcomes the restoring forces of the springs 39, but the Downward movement limited by the double T-shaped Stop pieces 33, which on the through the recesses 32nd formed projections come to rest.

The inserts 23 can be of the required dimensions for Stamps of every shape and size are prefabricated separately, resulting in a significantly cheaper workflow at Manufacturing leads. If necessary, the Pressure plates 5 '', e.g. B. when worn, just as easily have been replaced so far.

The embodiment of Figure 6 is intended to indicate how a larger printing plate can be attached to a stamp in the sense of the invention. Combined two-way stops 45 and, on the other hand, spacers 46 are used, which can be arranged in a suitable manner distributed over the surface of the pressure plate 47 in question. The bellows 40 corresponds to that according to FIG. 3. The pressure plate 47 is fastened to the lower plate 25 'of the insert 23' shown by means of screws 48.

The two-way stop 45 shown comprises a bolt, a lower section 49 of larger diameter and includes an upper portion 50 of smaller diameter. A shoulder 51 is thereby formed. Section 29 is welded to the lower plate 25 '. The top section 50 passes through the upper plate 24 'and enables one therein Shift. A screw 52 is inserted through the bolt and screwed to the lower plate 25 '. Under the head this screw is a stop plate 53, which the movement of the lower part of the insert down limited. On the other hand, the shoulder 51 forms a stop up. The possible stroke in this example is 12 mm. In addition to shoulder 51, there are others at exactly the same height Thrust pieces 46, which are designed as strips or blocks, in the example by hole welding with the lower plate 25 ' welded. Because the impact mentioned between these Stops and the top plate 24 'occurs is for a to ensure a sufficiently large total impact area. The number and distribution of the two-way stops and the Plates over the stamp area depend on their format and Size down.

1

Auflastplatte

1'

Auflastplatte

1''

Auflastplatte

2

Stempelschaft

2'

Stempelschaft

2''

Stempelschaft

3

Kopfplatte

4

Fußplatte

4'

Fußplatte

4''

Fußplatte

5

Druckplatte

5'

Druckplatte

5''

Druckplatte

6

Membranaufnahmeteil

6'

Membranaufnahmeteil

7

Haltering

8

Schraube

9

Anschlagfläche

10

Federschraube

11

Druckfeder

12

Membran

13

Befestigungsring

14

Schraube

15

Leitung

16

Verschraubung

17

Verteilerstück

17'

Verteilerstück

18

Dreiwegeventil

19

Druckluftversorgungsleitung

20

Versteifungsschiene

21

Schraube

22

Dichtungsring

23

Einsatz

23'

Einsatz

24

obere Platte

24'

obere Platte

25

untere Platte

25'

untere Platte

26

Führungshülse

27

Führungsbolzen

28

Distanzleiste

29

Distanzleiste

30

Distanzleiste

31

Distanzleiste

32

Aussparung

33

Anschlagstück

34

Schraube

35

Schraubenbolzen

36

Mutter

37

Bohrung

38

Randaussparung

39

Druckfeder

40

Balgen

41

Anschlußplatte

42

Druckluftschlauch

43

Schraube

45

Zwei-Richtungs-Anschlag

46

Distanzstück

47

Druckplatte

48

Schraube

49

Abschnitt, unten

50

Abschnitt, oben

51

Schulter

52

Schraube

53

Anschlagscheibe

The advantages of attaching a pressure plate to a stamp in this way, in which a striking in the rhythm of the vibrating vibrations occurs in the post-compression phase by appropriate dimensioning of the air pressure of the bellows, are summarized again as follows. The tolerance of the height or thickness of the manufactured Concrete body is 1 mm. The compaction of the concrete and thus the strength of the finished products is the same throughout. Large plates of relatively small thickness with a crack-free surface can also be produced, so that these plates have a low tendency to break. The surface is structured evenly. The previously observed sticking of the shaped concrete slabs to the stamp printing plates no longer occurs, rather the printing plates detach without errors.

1

load plate

1'

load plate

1''

load plate

2

punch shaft

2 '

punch shaft

2 ''

punch shaft

3

headstock

4

footplate

4 '

footplate

4 ''

footplate

5

printing plate

5 '

printing plate

5 ''

printing plate

6

Membrane receiving part

6 '

Membrane receiving part

7

retaining ring

8th

screw

9

stop surface

10

spring screw

11

compression spring

12

membrane

13

fixing ring

14

screw

15

management

16

screw

17

manifold

17 '

manifold

18

Three-way valve

19

Compressed air supply line

20

stiffening rail

21

screw

22

sealing ring

23

commitment

23 '

commitment

24

top plate

24 '

top plate

25

lower plate

25 '

lower plate

26

guide sleeve

27

guide pins

28

spacer bar

29

spacer bar

30

spacer bar

31

spacer bar

32

recess

33

stop piece

34

screw

35

bolt

36

mother

37

drilling

38

edge recess

39

compression spring

40

scramble

41

connecting plate

42

Compressed air hose

43

screw

45

Two-way stop

46

spacer

47

printing plate

48

screw

49

Section, below

50

Section, above

51

shoulder

52

screw

53

stop disc

Claims (13)

1. Mould for use in a block-making machine for manufacturing concrete mouldings comprising a bottom mould part with at least one mould chamber and a top mould part with a load plate (1) carrying one or more die(s), there being as many dies (2 to 5) as mould chambers, the dies (2 to 5) comprising an end face pressure-exerting plate (5, 5', 5") and the mould chamber being designed to receive the die (2 to 5) and the die (2 to 5) with end face pressure-exerting plate (5, 5', 5") being movably guided in the height direction, with respect to the top mould part in a lifting range defined by stops (9, 33, 51, 53), the dies (2 to 5) being vertically guided on the load plate (1), characterised in that a pressure medium chamber with a movable wall and acting on the pressure-exerting plate (5, 5', 5") of the die and loaded by a pressure medium (19) is provided on the individual dies or on each die (2 to 5), wherein the lifting range of the die (2 to 5) with pressure-exerting plate (5, 5', 5") defined by stops can be changed by the effect of a pressure medium (19).
2. Mould according to claim 1, characterised in that the pressure medium is compressed air and the movable wall is a diaphragm (12)or a bellows (40).
3. Mould according to claim 1 or 2, characterised in that the dies comprise die shanks (2, 2") fastened to the load plates (1', 1") and carrying the movable pressure-exerting plates (5', 5", 47), and in that the pressure-medium chambers are arranged in the lower region of the dies.
4. Mould according to claim 1 or 2, characterised in that the die shanks (2) are movably mounted on the load plate (1) and are rigidly connected to the pressure-exerting plates (5) and in that the pressure-medium chambers are arranged approximately level with the load plate (1) and exert their compressive forces on the die shanks (2).
5. Mould according to claim 1, characterised in that a foot plate (4"), which is rigidly connected to the die shank (2") is provided on each die, and an insert (23, 23') is arranged between said foot plate and the pressure-exerting plate (5"), the insert having a top part with a top plate (24, 24') and a bottom part which is guided so as to be vertically movable with respect to said top part and has a bottom plate (25, 25'), the top plate being screwed to the foot plate and the bottom plate being screwed to the pressure-exerting plate, and in that the insert (23, 23') contains at least one bellows (40) which can be pressurised by compressed air and the stops (33, 28 to 31, 46, 51, 53) for limiting the lifting range of the two parts.
6. Mould according to claim 5, characterised in that interengaging guide bolts (27) and guide sleeves (26) are arranged on the two parts of the insert (23).
7. Mould according to claim 5, characterised in that spacer pieces (28 to 31, 46) are provided on one of the two plates (24, 25, 24', 25) of the insert (23, 23') as stops to limit the upward travel of the pressure-exerting plates (5", 47).
8. Mould according to claim 5, characterised in that double-T-shaped stop pieces (33) are provided on one of the plates (24, 25) of the insert (23) as stops to limit the downward travel of the pressure-exerting plates (5"), the stop pieces engaging in double-T-shaped recesses (32) of spacer pieces fastened on the other plate.
9. Mould according to claim 5, characterised in that a bolt (49, 50) which is fastened on the bottom plate (25') of the insert (23') passes through the other plate (24'), with a guiding action, the bolt having a widened head (53) above said other plate of the insert and a bearing shoulder (51) beneath the other plate.
10. Method for mechanically producing concrete moulded parts with a mould according to any of the preceding claims, characterised by the following steps:

    a) The mould chamber(s) is (are) filled with core concrete.

    b) The core concrete is pre-compacted by pressurised pressure medium chambers.

    c) The top mould part is raised add the mould chamber(s) filled with face concrete.

    d) The total concrete poured in is post-compacted with reduced pressure medium pressure.
11. Method according to claim 10, characterised in that the pressure is reduced further during the course of post-compacting.
12. Method according to claim 11, characterised in that the pressure is continuously lowered.
13. Method according to claim 11, characterised in that the pressure is reduced to zero.

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