Cyclone separation device

Abstract

A cyclone separation device includes a cyclone chamber for separating dirt from incoming air, a dirt collecting chamber arranged adjacent to the cyclone chamber for collecting dirt particles separated from air, and a dirt duct between the cyclone chamber and the dirt collecting chamber for allowing dirt particles to exit the cyclone chamber into the dirt collecting chamber. To reduce the generation of noise-generating air vortices, the dirt duct has an edge protruding into a direction at an angle to the dirt duct at an exit ridge of the cyclone chamber that is first encountered by the air rotating in the cyclone chamber. Preferably, the edge is formed by a tangential extension of a wall of the cyclone chamber. A vacuum cleaner advantageously includes such a cyclone separation device.

Claims

1. A cyclone separation device, comprising: a cyclone chamber to separate dirt from air; a dirt collecting chamber, arranged adjacent to the cyclone chamber, to collect dirt particles separated from the air; and a dirt duct between the cyclone chamber and the dirt collecting chamber to allow the dirt particles to exit the cyclone chamber into the dirt collecting chamber, wherein the dirt duct includes a pair of opposite side walls and a bottom wall adjoining the pair of opposite side walls, and wherein the dirt duct has an edge protruding into a direction at an angle to the dirt duct at an exit ridge of the cyclone chamber that is first encountered by the air rotating in the cyclone chamber, wherein the dirt duct is integral to the cyclone chamber and extends into the dirt collecting chamber, and wherein the bottom wall connects to the exit ridge of the cyclone chamber.

2. The cyclone separation device as claimed in claim 1, wherein the edge is formed by a tangential extension of a wall of the cyclone chamber.

3. The cyclone separation device as claimed in claim 1, wherein a width of the edge is at least 5 mm.

4. The cyclone separation device as claimed in claim 3, wherein the width of the edge is at least 8 mm.

5. The cyclone separation device as claimed in claim 3, wherein the width of the edge is at least 12 mm.

6. The cyclone separation device as claimed in claim 1, wherein the edge extends along an entire height of the dirt duct.

7. The cyclone separation device as claimed in claim 1, wherein the dirt duct extends in a longitudinal direction that is radial to the cyclone chamber.

8. A vacuum cleaner comprising the cyclone separation device as claimed in claim 1.

9. The cyclone separation device as claimed in claim 2, wherein a thickness of the edge is different from a thickness of the wall of the cyclone chamber.

10. The cyclone separation device as claimed in claim 1, wherein the cyclone chamber comprises a cylinder-shaped vortex finder having a plurality of stationary vanes at an outer circumference.

11. The cyclone separation device as claimed in claim 1, wherein the edge is perpendicular to a wall of the dirt duct.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows an embodiment of a cyclone separation device in accordance with the present invention.

DESCRIPTION OF EMBODIMENTS

(2) FIG. 1 shows an embodiment of a cyclone separation device in accordance with the present invention. Like in US2014373307, the cyclone separation device has a cyclone chamber C, a dirt collecting chamber D arranged adjacent to the cyclone chamber C for collecting dirt particles separated from air, a dirt duct DD between the cyclone chamber C and the dirt collecting chamber D for allowing dirt particles to pass from the cyclone chamber C towards the dirt collecting chamber D. As shown in the FIGURE, the dirt duct DD may generally extend in a longitudinal direction that is radial to the cyclone chamber C. The cyclone chamber C may have a cylinder-shaped vortex finder F having a plurality of stationary vanes at its outer circumference, or some other air exit for allowing air with a reduced amount of dirt to leave the cyclone chamber C. Air A is rotating clockwise in the cyclone chamber C. As shown, the dirt duct DD includes a pair of opposite side walls X and a bottom wall Y adjoining the pair of opposite side walls X. The dirt duct DD is integral to the cyclone chamber C and extends into the dirt collection chamber D and the bottom wall Y connects to the exit ridge of the cyclone chamber D.

(3) In accordance with a feature of the present invention, an edge E protrudes into the dirt duct DD at a first exit ridge R of the dirt duct DD. As a result, air cannot easily exit the cyclone chamber C into the dirt duct DD, and thus cannot easily produce vortices that result in noise. In this example, the edge E is formed by a tangential extension of the cyclone chamber wall, and has the same thickness as that wall. A width w of the edge E is at least 5 mm, and preferably at least 8 mm, and more preferably 12 mm. It is practical if the edge E extends along the entire height H of the dirt duct DD, as shown.

(4) It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. The dirt duct DD may have a roof. The edge E might also be a serrated edge, or an edge placed at an angle with regard to the air flow direction, etc. . . . in order to negate coherent vortex shedding. For example, the edge E may be perpendicular to a wall of the dirt duct DD. The thickness of the edge E may be different from the thickness of the wall of the cyclone chamber C. In general, preventing coherent (simultaneously generated) vortices reduce the attenuation of the Helmholtz system. To improve cleanability, a space between the edge E and the wall of the dirt duct DD may be filled so that dirt does not stick in that space, provided that this is not done in such a way, that air can easily follow a curve from the cyclone chamber C into the dirt duct DD.

(5) Apart from use in vacuum cleaners, the invention can be used in cyclone applications which can be found in different industries like the mining industry, air treatment systems, etc.

(6) In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word “comprising” does not exclude the presence of elements or steps other than those listed in a claim. The word “a” or “an” preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, but the cyclone chamber C and the dirt collecting chamber D may also be molded in one piece. In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. Measures recited in mutually different dependent claims may advantageously be used in combination.