DK2301692T3

DK2301692T3 - METHOD AND DEVICE FOR Unpacking and sand broadcast mold pieces

Info

Publication number: DK2301692T3
Application number: DK09170147.4T
Authority: DK
Inventors: Artur Bissert; Markus Henkel; Urs Gerber; Bernhard Schädle
Original assignee: Fischer Georg Automobilguss
Priority date: 2009-09-14
Filing date: 2009-09-14
Publication date: 2016-04-11
Also published as: EP2301692A1; ES2560777T3; EP2301692B1; PT2301692E; SI2301692T1; PL2301692T3

Description

Method and device for packing and dispatching casting mould parts Description

The invention relates to a device for the separation and desanding of castings that have been cast in moulding sand and in moulding boxes comprising a compressed air container, an air-permeable and sand-permeable supporting base and a receiving container.

In the foundry, castings, especially cast iron castings, are cast in sand moulds. A hollow shape, into which the liquid metal is poured, is formed in the sand inside a moulding box, which is composed of an upper half-box and a lower half-box. If the casting is to have cavities, so-called cores are introduced into the hollow shape ahead of the casting process. After the casting process, the casting or castings must be freed from the moulding sand and the cores. Vibrating devices or shaking devices and/or devices that wash away the sand with water jets are used for separating the moulded parts. The casting still requires to be freed from the moulding sand.

Disclosed in CH 640 159 A5 is a method and a plant for wet desanding. The mould package is placed on a rotating grid and is sprayed by water jets from nozzles at a pressure of up to 800 bar. The water jet may result in crack formation in the castings. Wet desanding is only economically viable if the water and the sand can be reused economically again.

Disclosed in EP 992 323 A2, furthermore, are a method and a device for desanding cast components. The moulding box is placed on a sand-permeable and air-permeable supporting base. Before the cast components are desanded, the upper box of the two-part moulding box is removed. The fluid that is used for desanding is bundled into a cutting jet and is brought to bear on the surface of the sand at a single point or in a linear fashion. After desanding, the cast components remain in their original position and are transported away by a robot.

Based on the prior art, the object of the invention is to propose a device for separating and desanding castings, which ensure complete desanding of the moulded part associated with the lowest possible energy and equipment costs.

This object is accomplished by a device for the separation and desanding of castings that have been cast in moulding sand and in moulding boxes comprising a compressed air container, an air-permeable and sand-permeable supporting base and a receiving container, the compressed-air container having an opening corresponding to the cross-sectional area of the moulding box and being arranged directly above the surface of the sand by a sealing means.

Preferred further developments of the invention will become apparent from the dependent claims.

It is advantageous, when separating and desanding, for the compressed air pulse to be able to act as effectively as possible on the surface of the moulding sand. This is achieved in that the moulding box is not opened, and in that the upper half of the moulding box is not removed. The moulding box is placed on the upper edge of the receiving container.

This is also achieved in that the air-permeable and sand-permeable supporting base is disposed at a distance, being less than half the height of one half of the moulding box, below the upper edge of the receiving container.

An illustrative embodiment of the invention is described with reference to the Figures. In the drawings:

Figure 1 depicts a section through a device according to the invention for separating and desanding a moulding box with a casting during the build-up of pressure,

Figure 2 depicts a section through the device in Figure 1 immediately after separating and desanding,

Figure 3 depicts the casting in Figure 2 on the air-permeable and sand-permeable supporting base after separating and desanding, and

Figure 4 depicts the casting in Figure 3 on the air-permeable and sand-permeable supporting base after removal of the moulding box. A device 1 for the separation and desanding of castings 7 that have been cast in moulding sand 8 and in moulding boxes 6 is represented schematically and in section in Figure 1. The moulding box 6 consists of two moulding box halves arranged horizontally one above the other, being an upper box 10 and a lower box 11. A casting 7 is represented schematically in the moulding sand 8. The moulding box 6 is connected to the device 1 for separating and desanding in an air-tight manner by sealing means 12, 13 on the top side and the bottom side. Apart from the sealing means 12, 13, the device 1 substantially comprises a compressed air container 2 for charging the surface of the sand of the upper box 10 with compressed air, an air-permeable and sand-permeable supporting surface 3 and a collecting container 4 for collecting the moulding sand 8.

The upper box 10 is not removed in conjunction with separation. The compressed air container 2 has an opening that is substantially the same size as the surface of the moulding sand 8 in the moulding box 6. The air pressure is increased inside the compressed air container 2, once the device 1 has been sealed to the moulding box 6 with the sealing means 12, 13. The moulding sand 8 together with the casting 7 is pressed from the moulding box 6 with a sufficiently high pressure. The compressed air container 2 is formed like a bell with a relatively low height. The compressed air acts uniformly on the entire surface of the moulding box 6, as indicated by the arrows in Figure 1.

The air-permeable and sand-permeable supporting base 3 is disposed within the collecting container 4. The supporting base 3 can be configured, for example, as a grid, a pallet, a conveyor belt or some other air-permeable and sand-permeable transport means. The air-permeable and sand-permeable supporting base 3 is arranged at a distance from the lower edge of the moulding box 6. The distance between the upper surface of the sand in the lower box 11 and the supporting base 3 is less than half the height of the lower box 11. This ensures that the moulding sand 8 is able to come loose from the casting 7 during separation. The distance between the moulding box 6 and the supporting base 3 should be kept as small as possible in order to prevent damage to the desanded casting 7 as it falls onto the base 3.

The situation after separating and desanding is shown in Figure 2. The moulding sand 8 is present in the collecting container 4, and the casting 7 is present on the supporting base 3. The device 1 is still closed, although it is in the unpressurized state. In this state, the pressurized air container 2 and the receiving container 4 may be removed. If the casting 7 is resting on a conveyor belt, the casting 7 may also be removed from the device 1 for separating and desanding together with the now empty moulding box 6.

The subsequent situation during separating and desanding is represented schematically in Figure 3. The moulding box 6 is transported in its entirety to the moulding plant, i.e. without parting the upper box 10 and the lower box 11. In the moulding plant, the mould halves are parted, are filled with moulding sand 8 and are pressed by a pattern into the correct shape, and, where appropriate, are provided with core material and are then guided to the casting station.

The casting 7 resting on the air-permeable and sand-permeable supporting base 3 after unpacking and desanding is represented in Figure 4. The casting 7 can be transported on the grid 3 to the next processing station, such as a casting cleaning device.

With the apparatus 1 described here, the castings 7 are separated and desanded at a single location. Transport to a further part of the plant is not necessary. Parting of the moulding box halves 10, 11 in advance is not desirable because the pressure build-up in the compressed air container 2 only works well if the compressed air container 2 is set directly on top of the moulding box 6. Separating and desanding with compressed air needs no water and no costly regeneration or drying.

Because no grid or grating is present immediately below the moulding box 6 in the separating device 1 itself, and because the moulding sand 8 is able to disperse freely downwards from the box after separation, the frequently abrasive sand, which is forced from the moulding box 8 at high speed, will not cause damage or excessive wear to any parts of the system.

Claims

PROCEDURE AND APPARATUS FOR UNPACKING AND SHIPPING OF CASTLE PARTS

Device (1) for unpacking and sanding mold parts (7) molded in mold sand (8) and in mold casters (6), comprising a compressed air container (2), an air and sand-permeable substrate (3) and a collecting container (4), characterized in that the compressed air container (2) has an opening corresponding to the cross-sectional area of the mold box (6) and which is arranged immediately above the sand surface by means of a sealant (12).

Device (1) for unpacking and sanding mold parts (7) molded in mold sand (8) and in mold boxes (6) according to claim 1, characterized in that the air and sand-permeable substrate (3) is arranged at a distance below the mold box (6) in the collecting container (4).

Device (1) for unpacking and sanding mold parts (7) molded in mold sand (8) and in mold boxes (6) according to claim 1 or 2, characterized in that the distance between the upper edge of the collecting container (4) and the upper edge of the air and sand permeable substrate (3) is less than half the height of one half of the mold box (6).

Device (1) for unpacking and sanding mold parts (7) molded in mold sand (8) and in mold boxes (6) according to one of claims 1 to 3, characterized in that the air and sand-permeable substrate ( 3) is designed as a means of transport, for example as a grate or pallet for the mold parts (7).

5th

Device (1) for unpacking and sanding mold parts (7) molded in mold sand (8) and in mold boxes (6) according to one of claims 1 to 3, characterized in that the air and sand-permeable substrate (3) is designed as a conveying means, for example as a conveyor belt for the mold parts (7).