DE29805875U1 - Molding machine - Google Patents

Description

Applicant:

Mister

Rainer Kienle

Parioramaweg

D-8 6391 Stadtbergen

Representative:

Patent attorneys

Dipl.-Ing. H.-D. Ernicke

Dipl.-Ing. Klaus Ernicke

Schwibbogenplatz 2b

D-86153 Augsburg

Date:

01.04.1998

871-21 he/he

- 1 DESCRIPTION

Forming machine

The invention relates to a molding machine for producing preferably boxless molds with the features in the preamble of the main claim.

Such a molding machine is known from DE-C-32 06 169 and DE-U-296 10 658. It has two press units with press rams, a machine frame that absorbs the pressing forces and has two movably mounted molding boxes, a movable pattern plate carrier and a vacuum device with which the molding boxes can be filled with a flowable molding material, in particular molding sand, from a material supply by suction pressure. The known molding machine has a hollow pattern plate carrier through which the suction vacuum is directed into the molding boxes. The molding sand then shoots into the interior of the molding boxes through filling openings in the side walls.

Other molding machines are known from practice in which thin-walled, solid model plates are used, through which no suction air flow can be directed. In these molding machines, the molding boxes are filled axially with molding sand through shot slots, whereby the molding sand is shot in under a high external overpressure. The molding boxes can have perforated side walls or other openings through which the air in the molding boxes can be displaced during the filling process.

It is an object of the present invention to provide a molding machine with a different possibility for filling the molding boxes.

The invention solves this problem with the features in the main claim.

The inventive design of the molding box(es) or alternatively or additionally of the pressing ram(s) of the pressing units offers improved and faster filling of the molding boxes by means of negative pressure. The available suction cross-section can be larger than in the prior art. In addition, the negative pressure connections can be simplified, which can result in lower construction and cost expenditure.

The technology according to the invention can be used with any molding machine. It is particularly advantageous to use it on a molding machine with the basic components according to DE-C-32 06 169 or DE-U-296 10 658. The hollow and correspondingly large model plate carrier used here can be replaced in favor of a smaller construction. In addition, the model plate does not need to contain any openings for the suction air. The technology according to the invention also allows conventional model plates from other manufacturers that are solid and thin-walled to be used on the molding machine. In principle, the model plates in the molding machine according to the invention can be of any type and design.

In the preferred embodiment, the wall of the molding boxes is double-walled and has one or more air channels that are connected to the through-openings. This allows the suction air to be held within the wall and directed to one or more suitable connections. There are any number of suitable designs for these connections. In the preferred embodiment, these are single- or multi-armed rigid booms that are preferably moved along with the molding boxes and automatically couple to the vacuum device in the firing position.

The vacuum device with its shot valves can also be designed more simply and is easier to control. Overall, the molding machine is less complex to build and therefore more cost-effective. Operational reliability also benefits from the improved kinematics.

Advantageous embodiments 10 of the invention are specified in the subclaims.

• · · · ■ I •••9 ■ ··· ·

The invention is illustrated by way of example and schematically in the drawings. In detail,

Figure 1: a moulding machine in front view with the press box extended,

Figure 2: a cross section through the molding machine

according to section line II-II of Figure 1,

Figure 3: a cross section according to Figure 2 in

Firing position with mold boxes moved together and

Figure 4: a broken top view of the mold boxes

according to arrow IV of Figure 3.

Figures 1 to 3 show, by way of example, a molding machine (1) which, in its basic components, has largely the same design as the molding machines according to DE-U-296 10 658.

The molding machine (1) has a preferably rectangular, frame-like and symmetrical machine frame (2) which is formed by a lower and upper cross yoke and two side parts (3,4). In the free interior of the machine frame (2) there are two molding boxes (16,17) which are guided and held vertically on the facing inner side walls of the side parts (3,4) via lateral box guides (9). The molding boxes (16,17) are moved up and down by means of two pressing units (10,11) which are guided and mounted in the cross yokes.

The machine frame (2) absorbs the high pressing forces exerted by the pressing units (10, 11), which act essentially in a vertical direction. In the operating position, the side parts (3, 4) are rigidly connected to the two cross yokes. However, the side parts (3, 4) can be released from the rigid connection and moved sideways for assembly, maintenance and conversion purposes. This opens the machine frame (2) on at least one side and exposes and makes its interior accessible.

The side parts (3,4) are designed as hollow boxes and consist of strong box-shaped sheet metal profiles which safely absorb the reaction forces introduced into them during the pressing process. In an alternative design, separate support columns or similar other anchors can also be present to absorb forces. The hollow side parts (3,4) contain a supply of the flowable molding material (5), preferably molding sand, with which the molding boxes (16,17) are filled in the manner described below. The molding material (5) is preferably filled into the side parts (3,4) through an opening at the top using suitable conveying means.

In the preferred embodiment, the side parts (3,4) are arranged so that they can pivot about a pivot bearing (6) located underneath. With this arrangement, discharge openings can be created below the side parts (3,4) and between the journal bearings (6), through which the finished mold bales (39,40) can be transported away. The side openings of the U-shaped lower part of the machine frame (2) serve to eject the mold bales (39,40) with a suitable conveyor device (42) using pallets (41). The lower pressing unit (12) can be at least partially sunk into the ground.

The side parts (3,4) are connected to the upper cross yoke by means of a suitable detachable fastening. They are also positively connected to the cross yoke via a protruding bracket to support the high pressing forces.

The molding boxes (16,17) are connected to the inner side walls of the side parts (3,4) or to the machine frame (2) via detachable box guides (9). The box guides (9) can be any suitable guides. They allow the molding boxes (16,17) to move vertically, but at the same time also ensure lateral support. When a side part (3,4) is released, the molding boxes (16,17) can still be positively connected to the other side part (4,3) and therefore cannot fall off or fall down.

The pressing units (10, 11) consist, for example, of hydraulic cylinders, each of which has a pressing ram (12, 13) at the end of the piston rod. The molding boxes (16, 17) consist of a substantially rectangular wall (18) which is open at the top and bottom and into which the pressing rams (12, 13) can be inserted with a vertical movement. The molding boxes (16, 17) are placed on a model plate carrier (26) which can be moved in and out transversely to the carrier or on a model plate (28) which is detachably held by the carrier. The model plate (28) is preferably solid and relatively thin-walled. It can have a model (29) on one or both sides. The models (29) can be the same or different. The model plate (28) is slightly wider than the inner cross-section of the molding boxes (16, 17) so that the bottom and top of the molding boxes overlap on the edges of the model plate (28). Sealing can be achieved by inserting ring seals or the like.

The molding machine (1) has a device for filling the molding boxes (16, 17) with the molding sand (5) or another suitable molding material. The filling takes place by generating a high negative pressure in the molding boxes (16, 17) by means of a negative pressure device (30).

In the wall (18) of the mold boxes (16,17) there are filling openings (25) which, in the operating or firing position according to Figure 3, are aligned with blowing openings (7) (see Figure 1) on the inner walls of the side parts (3,4). In the operating or firing position, the molding sand (5) can be shot into the mold boxes (16,17) through the filling openings (25) due to the high negative pressure and fill them around the model and any cores that may have been inserted. Figure 2 shows an operator (43) inserting these cores. The molding sand (5) that has been shot in is then further compacted by the pressing units (10,11).

In the retracted position of the mold boxes (16, 17) shown in Figures 1 and 2, the filling and blowing openings (25, 7) are moved apart and alternately closed by the wall (18) of the side parts (3, 4). In this position, no molding material (5) can escape from the side parts (3, 4). Additional nozzle devices (8) are arranged in the area of the blowing openings (7) on the outside of the side parts (3, 4). Atmospheric air or compressed air is supplied via these, which supports and evens out the flow of molding sand (5) into the mold boxes (16, 17).

The model plate carrier (26) has a feed device (27) with which it can be moved forwards and backwards. The model plate carrier (26) is thereby moved into and out of the free space enclosed by the machine frame (2) and the retracted mold boxes (16, 17). In the embodiment shown,

the pattern plate carrier (26) with the pattern plate (28) is mounted on one side and cantilevered. In the operating position it can be held freely suspended between the mold boxes (16,17) in the machine frame (2). Alternatively, a rail guide can also be provided on the inner walls of the side parts (3,4).

The molding boxes (16, 17) can be connected to the press rams (12, 13) via simple drivers. In the preferred embodiment, the molding boxes (16, 17) are equipped with special driver devices (14, 15). These ensure an exact and synchronous advance and retraction movement of the molding boxes (16, 17) with the press rams (12, 13). The driver devices (14, 15) preferably consist of controllable hydraulic cylinders.

To generate the vacuum in the mold boxes (16, 17), the molding machine (1) has a vacuum device (30) with a large vacuum container (31). A strong vacuum can be generated in this by suitable suction pumps or the like (not shown). The vacuum container (31) is preferably located laterally next to the side parts (3, 4) and is arranged in a fixed position. The feed device (27) of the model plate carrier (26) can pass through it. In the container wall (36) facing the molding machine (1), it has one or more, preferably at least two, controllable shot valves, which are explained in more detail below.

To generate the vacuum, the molding boxes (16, 17) have one or more passage openings (21, 22) in the wall (18) through which the negative pressure can be directed into the box interior. These passage openings (21, 22) are connected to the negative pressure device (30) in a suitable stationary or movable manner. As shown in Figure 4 in the top view, the passage openings (21, 22)

preferably arranged on the long sides of the wall (18), while the filling openings (25) are located on the transverse sides. However, passage openings (21, 22) can also be present on the transverse sides.

The wall (18) of the mold boxes (16, 17) is preferably double-walled. The passage openings (21, 22) are arranged on the inner walls (19). The outer walls (20) are solid except for the filling openings (25). An air channel (23) is formed between the inner and outer walls (19, 20) arranged parallel and at a distance from one another, which can be connected to the vacuum device (30).

In the preferred embodiment, the molding boxes (16, 17) have one or more, preferably two connections (24) for connection to the vacuum device (30). These are designed, for example, as channel-shaped rigid arms that connect to the transverse wall and are connected to the air channels (23). The connections (24) can be moved up and down with the molding boxes (16, 17).

The connections (24) extend towards the vacuum container (31) and open just before the container wall (36). In the extended box position shown in Figures 1 and 2, the connections (24) with their air ducts (23) open into the closed container wall (36) and are thereby closed. In the firing or operating position shown in Figure 3, when the press boxes (16, 17) are retracted, the connections (24) with their air ducts (23) are aligned with the firing valves (32) and automatically dock onto the vacuum device (30). The vacuum from the vacuum container (31) can be passed via the firing valves (32) through the connections (24) to the mold boxes (16, 17) with the double wall and from there into the box interior.

The shot valves (32) can be designed in any suitable manner. In the simple embodiment shown, they each consist of a passage opening (35) in the container wall (36) which can be closed by the valve. The shot valve (32) itself has a deflection head (33) with a preferably conical or truncated cone-shaped valve plate and a valve rod (34) which can be moved back and forth by a suitable drive (not shown).

In the closed position according to Figure 2, the deflection head (33) closes the passage opening (35). In the shot position according to Figure 3, it opens the passage opening (35) so that the suction air flow (38) can shoot from the mold boxes (16, 17) into the vacuum container (31). The valve drive can be controlled in a suitable manner and depending on the molding machine functions. The valve drive can be located inside or outside the vacuum container (31). Suitable seals (37) can be present at the passage openings (35) to seal the transition to the connections (24).

In the embodiment shown, the connections (24) with the press box (16, 17) are moved up and down relative to the stationary vacuum container (31). Alternatively, a kinematic reversal can also take place. In a further modification, instead of the rigid boom-like connections (24), suitable flexible suction lines can be provided, which are permanently connected to the vacuum device (30) and corresponding protection valves (32) and can follow the box movements due to their flexibility.

Otherwise, the connection between the mold boxes (16, 17) and the vacuum device (30) can be realized in any other suitable manner.

- 11 -

In a further modification of the embodiment shown, the press rams (12, 13) can alternatively or additionally also have through-openings (21, 22) (not shown) which are also connected to the vacuum device (30) via suitable connections. Flexible connections in the form of reinforced vacuum lines can be advantageous here.

The functional sequence of the molding machine (1) is as follows:

First, the press rams (12,13) and the empty mold boxes (16,17) are moved apart. The model plate carrier (26) is then moved into the free space from the side. The mold boxes (16,17) and the press rams (1.2,13) are then moved in the manner described above and pressed against the model plate (28). The mold boxes (16,17) are then filled with molding sand (5) via the filling and blowing openings (25,7) using the negative pressure generated inside the box. The shot valves (32) are opened and the negative pressure device (30) sucks the air out of the mold boxes (16,17) via the passage openings (21,22), the air ducts and the connections (24). Following the subsequent compaction by the press rams (12,13), the mould boxes (16,17) with the moulded sand are moved apart again and the model plate carrier

(26) retracted (compare Figures 1 and 2).

The mold boxes (16,17) are then brought into contact with one another and lowered together into the passage opening on the underside of the frame. The mold boxes (16,17) are released from the filled and compacted molding sand (5) by the transport device (14,15) and moved away. The exposed mold bales (39,40) can then be transported via the conveyor device (42) to

- 12 -

a pallet (41) and transported further with it.

Modifications of the embodiment shown and described are possible in various ways. For example, the molding boxes (16, 17) can be arranged horizontally and lying down. The pressing units (10, 11) are also mounted differently accordingly. The blowing and filling openings (7, 25) can be arranged on one side of the box wall. The molding sand (5) can also be filled axially into the box interior if necessary.

In a further modification, the wall (18) of the press boxes (16, 17) can be designed as a single wall, with the through-openings (21, 22) being connected directly to the connection (24), which for this purpose has, for example, suction cups to cover these through-openings (21, 22). In a further modification, the connections (24) do not have to be rigidly or permanently connected to the mold boxes (16, 17).

Alternatively, a movable connection is also possible, such as in the embodiment shown between the connections (24) and the shot valves (32). It is also possible to have longitudinally movable connections (24) that act as a type of suction nozzle from the vacuum container.

(31) and placed against the mould boxes (16,17).

Furthermore, the molding machine (1) can be designed in any other way. It can also be designed as a simplified machine for individually filling one molding box at a time. Accordingly, the other machine components are present in smaller numbers and in a different design.

- 13 LIST OF REFERENCE SYMBOLS

1 molding machine

2 Machine frame

3 Side part, right, material supply

4 Side part, left., Material supply

5 Moulding material, moulding sand

6 bearings

7 Blow opening

8 Nozzle device

9 Box guide

10 Press unit

11 Press unit

12 press rams 13 press rams

14 Driving device, actuating cylinder

15 Driving device, actuating cylinder

16 Mould box

17 Mould box 18 Wall

19 Interior wall

20 Exterior wall

21 Passage opening

22 Passage opening 23 Air duct

24 Connection

25 Filling opening

26 model plate carriers

27 Feed device 28 Model plate

29 Model

30 Vacuum device

31 Vacuum tank

32 Shot valve

33 Deflection head, valve plate

34 Valve rod

35 Passage opening

- 14 -

36 Container wall 37 poetry 38 Air flow 39 Forraballen 40 Form bales 41 palette 42 Conveyor system 43 operator

Claims (9)

1. Moulding machine for producing preferably box-less moulds, which has one or more pressing units with pressing rams, a machine frame which absorbs the pressing forces, at least one movably mounted moulding box, a movable pattern plate carrier and a vacuum device for filling the moulding boxes with a flowable moulding material from a material supply, characterized in that the moulding box ( 16 , 17 ) and/or the pressing ram ( 12 , 13 ) have one or more passage opening(s) ( 21 , 22 ) in the wall which can be connected to the vacuum device ( 30 ). 2. Molding machine according to claim 1, characterized in that the wall ( 18 ) of the molding boxes ( 16 , 17 ) is double-walled and has one or more air channels ( 23 ). 3. Molding machine according to claim 1 or 2, characterized in that the molding boxes ( 16 , 17 ) have co-movable channel-shaped connections ( 24 ) for connection to the vacuum device ( 30 ). 4. Molding machine according to claim 3, characterized in that the connections ( 24 ) are designed as single- or multi-armed rigid arms and are arranged on the wall ( 18 ). 5. Molding machine according to one of claims 1 to 4, characterized in that the vacuum device ( 30 ) has a vacuum container ( 31 ) with one or more shot valves ( 32 ). 6. Molding machine according to claim 5, characterized in that the shot valves ( 32 ) are arranged in the wall ( 36 ) of the vacuum container ( 31 ). 7. Molding machine according to one of claims 1 to 6, characterized in that the shot valves ( 32 ) have seals ( 37 ) to the connections ( 24 ). 8. Molding machine according to one of claims 1 to 7, characterized in that the model plate ( 28 ) is designed as a narrow plate which can be equipped with a model ( 29 ) on both sides. 9. Molding machine according to claim 8, characterized in that the model plate ( 28 ) is solid and is detachably connected to the model plate carrier ( 26 ).