Device and Method for Filtering Particles from a Liquid in a Dishwasher

Abstract

A device is provided for filtering particles from a dishwashing fluid in a dishwashing machine, the dishwashing machine having a dishwashing container in which are disposed items to be subjected to the application of a dishwashing liquid thereto such that particles disentrained from the items during the application of a dishwashing liquid are entrained with the dishwashing liquid. The device includes a container operable to retain therein a predetermined quantity of a liquid mixed with at least one of a foam-forming substance and cleaning agents, the container including an arrangement for producing a flow of a gaseous fluid through the predetermined quantity of the liquid so as to generate a foam layer. The foam layer filters out from a dishwashing liquid passed through the foam layer a substantial fraction of particles entrained with the dishwashing liquid and such filtered-out particles are retained in the foam layer.

Description

A preferred embodiment of the device according to the invention is explained in detail hereinafter with reference to a drawing.

FIG. 1 shows a cross-section through a device according to the invention. The container 1 is preferably located in the lower area of the washing container but can also be arranged in another area of the dishwasher. A liquid 2 mixed with a foam-forming substance is introduced into the container 1 and a gaseous fluid 2, preferably atmospheric air, flows by means of a corresponding device 6 through openings 5 located in the bottom area of the container 1. Furthermore, the dishwashing fluid permeated with cleaning agents and possibly with food residues has properties similar to those of a liquid 2 mixed with a foam-forming substance and thus can also be used for foam formation. The dishwashing fluid enriched with cleaning agents and possibly also with food residues thus forms a liquid 2 mixed with cleaning agents.

When the gaseous fluid flows through the liquid 2 mixed with a foam-forming substance or the dishwashing liquid with food residues, a foam layer is formed, this being located on the surface of the liquid mixed with a foam-forming substance or the dishwashing fluid with food residue.

The dishwashing fluid contaminated with particles, especially food residue, is transported by the circulating pump via the path A to the means 4 and rains through these means 4, embodied as openings, onto the foam layer 3 whereby the particles located in the dishwashing solution, especially food residue, adhere to the foam bubbles and the cleaned dishwashing solution flows into the liquid mixed with foam-forming substance located therebelow.

The dishwashing solution thus cleaned is removed via the pipe system 7, the cleaned fraction being passed back via the path C into the washing cycle of the sump and after the dishwashing fluid has been cleaned, the contaminated foam and the remainder of the liquid flows along path C to the discharge pump and is removed there.

Claims

1-7. (canceled)

8. A device for filtering particles from a dishwashing fluid in a dishwashing machine, the dishwashing machine having a dishwashing container in which are disposed items to be subjected to the application of a dishwashing liquid thereto such that particles disentrained from the items during the application of a dishwashing liquid are entrained with the dishwashing liquid, the device for filtering particles comprising: a container operable to retain therein a predetermined quantity of a liquid mixed with at least one of a foam-forming substance and cleaning agents, the container including means for producing a flow of a gaseous fluid through the predetermined quantity of the liquid so as to generate a foam layer with the foam layer having filter properties in that the foam layer filters out from a dishwashing liquid passed through the foam layer a substantial fraction of particles entrained with the dishwashing liquid and such filtered-out particles are retained in the foam layer.

9. The device according to claim 8, wherein the means for producing a flow of a gaseous fluid are disposed in a bottom area of the container.

10. The method according to claim 8, wherein the means for producing a flow of a gaseous fluid includes apertures in a bottom sheet of the container.

11. The device according to claim 8 and further comprising means disposed in an upper area of the container operable to guide dishwashing fluid having particles entrained therewith into contact with the foam layer.

12. The device according to according to claim 8, wherein the container includes valve means in a bottom area of the container through which both the cleaning dishwashing fluid and the contaminated foam flow away separately.

13. A method for filtering particles from a quantity of liquid in a dishwashing machine, the method comprising: flowing a gaseous fluid through a predetermined quantity of a liquid mixed with at least one of a foam-forming substance and cleaning agents in a container so as to generate a foam layer with the foam layer having filter properties in that the foam layer filters out from a dishwashing liquid passed through the foam layer at least a fraction of particles entrained with the dishwashing liquid; andtrickling a dishwashing liquid having particles entrained therewith downwardly through the foam layer, wherein at least a fraction of the particles are retained in the foam layer, while collecting below the foam layer the quantity of dishwashing liquid from which the fraction of particles have been disentrained.

14. The method according to claim 13 and further comprising removing via suction foam that has been contaminated due to its entrainment of particles.