APPLICATION COMPONENT OF A ROTARY ATOMIZER MADE OF FOAM MATERIAL AND ITS PRODUCTION METHOD AND APPLICATION SPRAYING METHOD

Abstract

An application component for a rotary atomizer, having a base body which has an outflow surface for an application material that is to be atomized. In order to obtain a weight which is as low as possible while providing a highest possible strength, the base body is made in its interior at least in some regions of a material having cellular structures. Possible production methods of the component are, inter alia, an integral foam casting process, in particular an integral metal foam casting process, or a generative process.

Claims

1. An application component for a rotary atomizer comprising: a main body comprising an outflow surface for an application material to be atomized, wherein an interior of the main body is formed, at least in places, from a material with cellular structures.

2. The application component as claimed in claim 1, wherein the material with cellular structures is one or more of a metal foam, an aluminum metal foam, a plastics foam and/or a ceramic foam.

3. The application component as claimed in claim 1, wherein the material with cellular structures comprises two different materials.

4. The application component as claimed in claim 1, wherein the cellular structures have a defined geometry.

5. A method for producing an application component for a rotary atomizer comprising the following step: a) producing an application component with a main body which comprises an outflow surface for an application material to be atomized and an interior of which is formed at least in places from a material with cellular structures.

6. The method as claimed in claim 5, wherein production of the main body comprises the following steps: a) providing a mold which defines an outer contour of the main body; b) injection molding a solid material provided with a blowing agent.

7. The method as claimed in claim 5, wherein production of the main body comprises structural foam molding.

8. The method as claimed in claim 5, wherein production of the main body comprises an additive manufacturing process for producing the cellular structures.

9. A method for coating objects comprising the following steps: a) providing an application device with an application component as claimed in claim 1; and b) coating the objects using the application device.

10. The method as claimed in claim 5, wherein production of the main body comprises structural metal foam molding.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Exemplary embodiments of the invention are explained in greater detail below with reference to the drawings, in which:

[0037] FIG. 1 shows a section through a rotary atomizer with a bell cup of solid foam;

[0038] FIG. 2 shows a section through a rotary atomizer with a bell cup, comprising a foam-filled hollow article as bell cup;

[0039] FIG. 3 shows a section through a rotary atomizer with a bell cup of structural foam.

DESCRIPTION OF PREFERRED EXEMPLARY EMBODIMENTS

[0040] FIG. 1 shows a rotary atomizer 10 comprising a bell cup 14 as application component, said bell cup being mounted by way of a bearing 12 and rotating rapidly when in operation.

[0041] The bell cup 14 comprises a main body 16, the mass of which makes up a major part of the total rotating mass. A substantially internally tapered outflow surface 18 is provided on the main body 16 of the bell cup 14, to which surface coating material to be applied is fed by a feed pipe 20. Through rotation of the bell cup 14, the coating material is brought to the edge of the bell cup 14 and atomized there. Further details of the mode of operation of such a rotary atomizer 10 are generally known and of no further significance for the present invention.

[0042] The main body 16 is made at least in its inner region, as indicated by the checked hatching, of a foam material 22, in particular a high strength aluminum foamed metal alloy. Such a foam material 22 constitutes a material with cellular structures, meaning that the main body 16 comprises a plurality of hollow cavities, the foam pores 24, in its interior, the intermediate webs 26 of which provide mutual support.

[0043] The main body 16 further comprises a skin 28, which smoothly encloses the inner region of the main body 16. In the region of the outflow surface 18, the skin 28 of the main body 16 is further provided with a friction- and wear-reducing coating, which is not visible in the figure.

[0044] FIG. 2 shows a rotary atomizer 110, which likewise comprises a bell cup 114 mounted by way of a bearing 112. The bell cup 114 in this case has a main body 116, in which an outer region 130 is molded from a solid material, for example a high strength aluminum alloy. An inner region further comprises a foam material 122, in particular a foamed aluminum alloy, which has a true density which is identical to or greater than that of the aluminum alloy of the solid material outer region 130. Due to the cavities in the foam material 122, however, a lower bulk density is obtained in the inner region than in the outer region. Such a bell cup 114 may for example be manufactured by sandwich construction.

[0045] FIG. 3 shows a rotary atomizer 210, in which the main body 216 of the bell cup 214 takes the form of a structural foam component. In this case, an outer region of a solid material merges continuously into an inner region of foam material 222.

[0046] Such a structural foam component may be produced by high or low pressure structural foam molding. In the low pressure method, a mold is underfilled with a melt mixed with blowing agents. The foaming melt then fills the mold. Vigorous cooling at the mold wall results in a compact outer region of solid material. The thickness of the outer region may be influenced, depending on process control and blowing agent concentration.

[0047] In the high pressure method, the mold is firstly completely filled under pressure. After a time delay, the mold volume is then enlarged for example by a core puller. This lowers the pressure abruptly and gases dissolved in the melt can expand in the as yet unsolidified inner region and foam the melt.

[0048] In this way, the main body 216 of the bell cup 214 may be produced in a single molding step.

[0049] Instead of a foam material, cellular structures with defined geometries may also be used in the above-described exemplary embodiments. Thus, for example a cellular structure in the form of a honeycomb may also be provided in the inner region of the main body 14. Such honeycomb structures may be produced using an additive manufacturing process such as for example a 3D metal printing method, such that the main body may likewise be produced substantially in one step.