DE2311867A1 - MOLDING MACHINE WITH A SAND SCRAPER - Google Patents

Description

D pi-Ing. Oipl. o «c. pubt.

DIETStfCH ISV / INS & Y?. March 1973

Tekfon 5417-2

Erwin Bührer , Schaffhausen

(Switzerland)

Molding machine with a sand scraper

The invention relates to a molding machine with a sand scraper with several molding units arranged on a turntable which a molding box placed on a model unit first is filled with sand, after which the sand is pre-compacted, then the excess sand is stripped off and finally the sand is completely compacted.

With the molding sand fed to the molding box halves by the sand dispensing device, an excess of sand forms during filling, which is scraped off between the pre-compaction and the final compaction to a predetermined height by means of a sand scraper.

A molding machine is known in which an empty molding box is removed from a transversely movable empty box device in the work process is fed and placed on the pattern unit of the molding machine. After the empty molding box has been put on, it is filled and shaking in the molding sand with subsequent moving away of the empty box device, one on the empty box device

309839/0422

ORIGINAL INSPECTS)

attached sand scraper scrapes off the excess sand. For the compaction of the mold, another ready-made box device, which is equipped with a press head and can be moved across, is used moved the form, with which the form is completely compacted, lifted off and is then moved away from the molding machine.

Another molding machine is known in which an empty molding box is fed to the pattern unit, this from a plunger the model unit is lifted and filled with sand from a sand feeder. Subsequently, an on a driving. plant arranged press head, with one attached to this. tiltable sand scraper, retracted across the mold across the molding machine. The sand scraper separates during this movement the excess molding sand from the mold. This is followed by the final compacting of the form and then moving away of the press head. At the same time, the sand scraper is brought into a so-called cutting position, which means that when the press head is moved away, the one that protrudes from the final compression is also brought into being Sand is separated away.

Known type of sand scrapers cannot be used for molding machines with several model units arranged on a turntable, because the excess sand to be scraped off is thrown onto the next molding box.

The invention is based on the object of a molding machine with to create a sand scraper, with an excess of sand of a molding box can be stripped, which is formed on one of the model units, one with several model units Turntable, is attached. Furthermore, the rotary movements of the turntable and the sand scraper should be carried out simultaneously take place and the stripping process between the pre-compaction and the final compression of the sand can be carried out in the molding box. 30 9839/04 22

ORIGINAL INSPtCTiD

This object is according to the invention specified in the claim solved.

An embodiment of the invention is shown in the drawing and is described in more detail below. It shows:

Fig. 1 is a section through a molding machine with a, with a sand scraper provided with a sand dispensing device in a simplified representation, and

FIG. 2 shows a plan view of FIG. 1 along the line I-I _f

1 and 2 show part of a molding machine with a turntable 12 having a plurality of model units 17, in a simplified representation. A molding box 2, which is filled with precompacted molding sand 18 and thus forms a casting mold half 13, is placed on the pattern unit 17. In this state, the molding sand 18 protrudes beyond the molding box upper edge 6 by the distances 3, 8, the distance 3 being referred to as excess sand. The ^s distance 8 denotes a predetermined distance of a scraper bar 7 of the sand scraper 1 from the upper edge of the molding box 6 is. The hub 16 is fixedly arranged on a rotary column 5, which is movable by means of a schematically illustrated gear 20, 21 that engages with the column 22 of the turntable 12 in such a way that the turntable 12 counterclockwise 9 and the rotary column 5 clockwise 4 It is also possible to reverse the direction of rotation of the turntable 12 and the rotating column 5. The upstanding flat profile 11 has a wiper strip 7 on the narrow side facing the upper edge 6 of the molding box 2, which is preferably exchangeable and adjustable in height on the flat profile 11 is.

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■ - 4 -

It is possible to have several squeegees in relation to the molding cycle 7 to be provided, which come into operation alternately. In the embodiment shown, for example, there are two diametrically arranged scraper strips 7 are used, one strip consisting of: function via one leading to the molding box 2 ' Feed device 14 is pivoted. In the area of the strips 7, the filling frames 10 can be raised and lowered on the rotating column attached. A sand dispensing device provided above the filling frame 10 is not shown. - - "

The mode of operation is as follows: After the molding box placed on the model unit has been filled with molding sand and the molding sand has been pre-compacted during the molding process, the molding unit is moved counterclockwise 9 to move the molding box from pre-compression to final compression. Simultaneously with the rotary movement of the model unit, the rotary movement of the sand scraper takes place in a clockwise direction 4 _r, with the amount of excess sand touched by the squeegee 7 being stripped off in a movement relative to the rotary movement of the model unit. At the same time, another model unit and another molding box are brought into the filling position.

The advantages that can be achieved with the present invention are in particular that there are no unproductive cycle movements in the molding cycle and there are several model units from the sand scraper can be operated. The excess, stripped off sand is thereby removed from the area of the following on the turntable 12 Model unit carried away. The aforementioned counter-rotating movement of the turntable 12 and the scraper 1 also has a special one "grinding" relative movement between the mold surface and the The result is a scraper, whereby the amount of sand to be scraped off is gradually wiped off the mold surface without a build-up of the sand on the scraper occurs, which could cause the surface of the mold to tear.

309839/0422

Claims (4)

Claims 1. Molding machine with one sand scraper, with several on one Model units arranged on a turntable, with which a molding box placed on a model unit is first filled with sand is filled, after which the sand is pre-compacted, then the excess sand is stripped off and finally the sand "is completely compacted, characterized in that the turntable (12) with the placed on the model unit (17) Molding box (2) and a rotating column (5) with at least one scraper bar (7) connected to it via a gear (20, 21) are connected to one another in such a way that the turntable (12) and the rotary column (5) can be rotated in opposite directions, the Molding boxes (2) and the squeegees (7) in horizontal Move levels. 2. Molding machine according to claim 1, characterized in that um.die rotary column (5) several uniform wiper strips (7) are evenly distributed around the circumference of the column. 3. Molding machine according to claim 1, characterized in that - The scraper strips (7) of the sand scraper (1) can be dismantled are arranged. 4. Molding machine according to claim 1, characterized in that the height of the scraper bar (7) of the sand scraper (1) is adjustable. My / ip
February 8, 1973 309839/0422