ARRANGEMENT AND PROCESS FOR TREATING A SURFACE

Abstract

An apparatus and method for treating a surface with a jet utilizing a multiplicity of particles, using a mixing chamber for mixing a stream of propellant gas with the multiplicity of particles, a particle generator, which is designed to generate the multiplicity of particles and introduce them into the mixing chamber in a solid state, the particle generator having at least one screen plate, and it being possible for the multiplicity of particles to be formed in a solid state by pressing a solid starting material through the screen plate, a propellant gas line with a propellant gas nozzle for introducing the propellant gas into the mixing chamber, and an outlet from the mixing chamber for the stream of propellant gas.

Claims

1.-10. (canceled)

11. An apparatus for treating a surface with a jet comprising a multiplicity of particles, the apparatus comprising: a mixing chamber for mixing a stream of propellant gas with the multiplicity of particles, a particle generator, configured to generate the multiplicity of particles and introduce them into the mixing chamber in a solid state, the particle generator comprising at least one screen plate, wherein the multiplicity of particles are formed in a solid state by pressing a solid starting material through the at least one screen plate, a propellant gas line with a propellant gas nozzle configured to introduce the propellant gas into the mixing chamber, and an outlet from the mixing chamber for the stream of propellant gas.

12. The apparatus of claim 11, wherein the propellant gas nozzle is configured as a Laval nozzle.

13. The apparatus of claim 11, wherein the at least the mixing chamber and the propellant gas nozzle are configured to be rotationally symmetric about an axis of the apparatus.

14. The apparatus of claim 11, wherein the particle generator further comprises a conveying screw), configured to press the solid starting material through the at least one screen plate.

15. The apparatus of claim 11, wherein the mixing chamber is configured at least as part of an outer Laval nozzle.

16. The apparatus of claim 11, wherein the particles is formable at least partially with solid carbon dioxide.

17. A process for treating a surface with a jet comprising a multiplicity of particles, utilizing an apparatus according to claim 11.

18. The process according to claim 17, wherein the multiplicity of particles are generated by a solid starting material being pressed through the at least one screen plate.

19. The process according to claim 18, wherein the solid starting material comprises carbon dioxide.

20. The process according claim 17, wherein the treating of the surface comprises at least one of the following steps: cleaning the surface, and removing flash or burr from the surface.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The invention and the technical environment are explained in more detail below on the basis of the FIGURE. The FIGURE shows a particularly preferred exemplary embodiment, to which, however, the invention is not restricted. In particular, it should be pointed out that the FIGURE, and in particular the relative sizes represented, is/are only schematic. In the FIGURE:

[0044] FIG. 1 schematically shows a lateral sectional representation of an arrangement for treating a surface.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0045] FIG. 1 shows a lateral sectional representation of an arrangement 1 for treating a surface with a jet comprising a multiplicity of particles. The arrangement 1 comprises a mixing chamber 2 for mixing a stream of propellant gas with the multiplicity of particles. The arrangement 1 furthermore comprises a particle generator 8, which is designed to generate the multiplicity of particles and introduce them into the mixing chamber 2 in a solid state. The particle generator 8 has a screen plate 10 and a conveying screw 9. The multiplicity of particles can be formed in a solid state by pressing a solid starting material 12 through the screen plate 10 by means of the conveying screw 9. The particle generator 8 preferably has a particle generator chamber 14 with an inlet 13 through which the starting material or a substance for producing the starting material can be introduced. In this case, liquid carbon dioxide for example can be expanded through the inlet 13 into the particle generator chamber 14, with the result that solid carbon dioxide is formed as solid starting material and carbon dioxide gas in the particle generator chamber 14.

[0046] The arrangement 1 furthermore has a propellant gas line 3 with a propellant gas nozzle 4 configured as a Laval nozzle 5, which serves for introducing the propellant gas into the mixing chamber 2. The arrangement 1 also has an outlet 7 from the mixing chamber 2 for the stream of propellant gas. The mixing chamber 2 is configured as part of an outer Laval nozzle 11.

[0047] The mixing chamber 2 and the propellant gas nozzle 4 are configured to be rotationally symmetric about an axis 6 of the arrangement 1. Also, the outlet 7 is of round configuration.

[0048] With the arrangement presented and the process presented for treating a surface, a particularly uniform and particularly intensive treatment of the surface can be achieved. In this case, it is possible to use particularly large carbon dioxide particles having high kinetic energy, which have a particularly uniform and particularly well controllable particle size. This applies in particular to cleaning and removing flash or burr. The arrangement and the process may be used in particular in the production of wire or plastic products.

LIST OF DESIGNATIONS

[0049] 1 arrangement [0050] 2 mixing chamber [0051] 3 propellant gas line [0052] 4 propellant gas nozzle [0053] 5 Laval nozzle [0054] 6 axis [0055] 7 outlet [0056] 8 particle generator [0057] 9 conveying screw [0058] 10 screen plate [0059] 11 outer Laval nozzle [0060] 12 solid starting material [0061] 13 inlet [0062] 14 particle generator chamber

[0063] It will be understood that many additional changes in the details, materials, steps and arrangement of parts, which have been herein described in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims. Thus, the present invention is not intended to be limited to the specific embodiments in the examples given above.