Shroud and cyclonic cleaning apparatus incorporating same

Claim 2

A shroud means (50, 150, 250) for use in a cleaning apparatus (10) including a container (15) comprising a bottom (40d) and a sidewall extending to and meeting the bottom (40d), the sidewall having an interior surface (15), a dirty air inlet (27) which is oriented for supplying dirt laden air into the container (15) tangentially to the interior surface (15a) of the container (15) which has a circular cross-section and an air outlet from the container (15); a circular cross-sectioned cyclone (20) having a longitudinal axis mounted inside the container, the cyclone comprising a cyclone air inlet (36) at an upper end having a first diameter of the cyclone (20) in air communication with the air outlet of the container, an interior dirt rotational surface (20a) of frusto-conical shape for receiving an air flow from the air inlet (36) and for maintaining its velocity to a cone opening (20b) smaller in diameter than the diameter of the upper end of the cyclone (20), the air inlet (36) being oriented for supplying air tangentially to the surface (20a), an outer surface (20c) of frusto-conical shape, and a cyclone air outlet (33) communicating with the interior of the cyclone (20) adjacent the upper end of the cyclone; a dirt collecting receiver (40) extending from the cone opening (20b); and means for generating an airflow which passes sequentially through the dirty air inlet (27), the container (15), the cyclone air inlet (36), the cyclone (20), the dirt receiver (40) and the cyclone air outlet (33), the airflow rotating around the frusto-conical interior surface (20a) of the cyclone (20) and depositing the dirt in the receiver (40); the shroud means (50, 150, 250) being mountable on and around the outer surface (20c) of the cyclone (20), having opposed ends along the longitudinal axis and providing an air outlet from the container (15) into the air inlet (36) to the cyclone (20), characterised in that a portion of the shroud (50, 150, 250) has a cylindrical section (50c, 150c, 250c) with perforations (50e, 150e, 250e) which allow for the flow of the air from the container (15) to the cyclone inlet (36) and which is spaced from and parallel to the inside wall (15a) of the container (15) and in that the cylindrical section (50c, 150c, 250c) is joined to a web section (50d, 150d, 250d) an inside edge of which contacts the outside wall (20c) of the cyclone (20) and an outside edge of which is joined to the cylindrical section (50c, 150c, 250c).

Claim 3

A shroud means as claimed in claim 1 or 2, wherein there are a large number of the perforations (50e, 150e, 250e) through the cylindrical section (50c, 150c, 250c) so as to create a low differential pressure between an outside surface (50k, 150k, 250k) and an inside surface (50j, 150j, 250j) of the cylindrical section (50c, 150c, 250c) so that dirt is not drawn through the cylindrical section by the flow of air from the container (15) to the cyclone air inlet (36).

Claim 4

A shroud means (50, 150, 250) for use in a cleaning apparatus (10) including a container (15) comprising a bottom (40d) and a sidewall extending to and meeting the bottom (40d), the sidewall having an interior surface (15a), a dirty air inlet (27) which is oriented for supplying dirt laden air into the container (15) tangentially to the interior surface 15a) of the container (15) which has a circular cross-section and an air outlet from the container (15); a circular cross-sectioned cyclone (20) having a longitudinal axis mounted inside the container (15), the cyclone (20) comprising a cyclone air inlet (36) at an upper end having a first diameter of the cyclone (20) in air communication with the air outlet of the container, an interior dirt rotational surface (20a) of frusto-conical shape for receiving an air flow from the air inlet (36) and for maintaining its velocity to a cone opening (20b) smaller in diameter than the diameter of the upper end of the cyclone (20), the air inlet (36) being oriented for supplying air tangentially to the surface (20a), an outer surface (20c) of frusto-conical shape, and a cyclone air outlet (33) communicating with the interior of the cyclone (20) adjacent the upper end of the cyclone (20); a dirt collecting receiver (40) extending from the the cone opening (20b); and means for generating an airflow which passes sequentially through the dirty air inlet (27), the container (15), the cyclone air inlet (36), the cyclone (20), the dirt receiver (40) and the cyclone air outlet (33), the airflow rotating around the frusto-conical interior surface (20a) of the cyclone (20) and depositing the dirt in the receiver (40); the shroud means (50, 150, 250) being mountable on and around the outer surface (20c) cyclone (20), having opposed ends along the longitudinal axis and providing an air outlet from the container (15) into the air inlet (36) to the cyclone (20), characterised in that a portion of the shroud (50, 150, 250) has a perforated section (50c, 150c, 250c) with a large number of perforations (50e, 150e, 250e), spaced from the inside wall (15a) of the container (15) wherein a low differential pressured created between an outside surface (50k, 150, 250k) and an inside surface (50j, 150j, 250j) of the perforated section (50c, 150c, 250c) keeps dirt from being drawn through the perforated section (50c, 150c, 250c) by the flow of air from the container (15) to the cyclone air inlet (36) and wherein one of the ends of the,shroud means (50, 150, 250) is closed by the outer surface (20c) of the cyclone (20)

Claim 5

A shroud means as claimed in any one of the preceding claims, wherein the perforations (50e, 150e, 250e) through the perforated section (50c, 150c, 250c) are circular and are provided around a circumferential extent of the perforated section (50c, 150c, 250c) of the shroud means (50, 150, 250), which perforated section (50c, 150c, 250c) is cylindrical.

Claim 6

A shroud means as claimed in any one of the preceding claims, wherein the perforated section (50c, 150c, 250c) of the shroud means (50, 150, 250) is between 0.59 inches and 1.38 inches (1.5 cm and 3.5 cm) from the inside wall (15a) of the container (15) when in use.

Claim 7

A shroud means as claimed in any one of the preceding claims, wherein the shroud means (50, 150, 250) has a flanged section (50b, 150b, 250b) above the cylindrical section (50c, 150c, 250c), the flanged section (50, 150, 250) being locatable around the longitudinal axis at an end adjacent the air inlet (36) to the cyclone (20) which is in closely spaced relationship to the outside (20c) of the cyclone (20) so as to provide a chamber (32) leading to the inlet (36) to the cyclone (20) when in use.

Claim 8

A shroud means as claimed in any one of the preceding claims, wherein a disc means (50h, 150h, 250h) is provided at a lower longitudinal extent of the shroud means (50, 150, 250), the disc means (50h, 150h, 250h) being locatable around the axis of the cyclone (20) with a space between the interior surface (15a) of the container (15) and the disc means (50h, 150h, 250h) for passage of air, wherein, in use, the disc means (50h, 150h, 250h) aids in dirt removal in the container (15) by preventing some of the dirt from flowing into the air inlet (36) to the cyclone (20).

Claim 9

A shroud means as claimed in claim 8, wherein the shroud means (50, 150, 250) and the disc means (50h, 150h, 250h) form an integral unit slidable over the outside surface (20c) of the cyclone (20) such that the cone opening (20b) protrudes below and out of the unit, and wherein a lower section (50f, 150f, 250f) of the shroud means (50, 150, 250) depending from a radius of the web section (50d, 150d, 250d) of the shroud means (50, 150, 250) supports the disc means (50h, 150h, 250h) and is locatable in sealed relationship with the outside wall (20c) of the cyclone (20) so that, in use, the airflow in the container (15) must travel over the disc means (50h, 150h, 250h) and past an outside surface of a lower section of the shroud means (50, 150, 250) before passing through the openings (50e, 150e, 250e) in the cylindrical section (50c, 150c, 250c) leading to the inlet (36) to the cyclone (20).

Claim 10

A shroud means as claimed in claim 8 or 9, wherein the disc means (50h, 150h, 250h) is circular in cross-section.

Claim 11

A shroud means as claimed in any one of claims 8 to 10, wherein the disc means (50h, 150h, 250h) has a conical shape around the shroud means (50, 150, 250) such that, in use, a larger portion of the conical shape faces towards the bottom (40d) of the container (15).

Claim 12

A shroud means as claimed in claim 11, wherein the conical shape when viewed as a cross-section of the shroud means (50, 150, 250) and disc means (50h, 150h, 250h) through the longitudinal axis is at a downwardly inclined angle of about 7-1/2 to 20° from a line perpendicular to the longitudinal axis of the cyclone (20).

Claim 13

A shroud means as claimed in any one of claims 8 to 12, wherein the disc means (50h, 150h, 250h) is positioned about one third of the distance between the cone opening (20b) and the air inlet (36) of the cyclone (20) when in use.

Claim 14

Cleaning apparatus (10) including a container (15) comprising a bottom (40d) and a sidewall extending to and meeting the bottom (40d), the sidewall having an interior surface (15a), a dirty air inlet (27) which is oriented for supplying dirt laden air into the container (15) tangentially to the interior surface (15a) of the container (15) which has a circular cross-section and an air outlet from the container (15); a circular cross-sectioned cyclone (20) having a longitudinal axis mounted inside the container (15), the cyclone comprising a cyclone air inlet at an upper end having a first diameter of the cyclone in air communication with the air outlet of the container, an interior dirt rotational surface (20a) of frusto-conical shape for receiving an airflow from the air inlet (36) and for maintaining its velocity to a cone opening (20b) smaller in diameter than the diameter of the upper end of the cyclone (20), the air inlet (36) being oriented for supplying air tangentially to the surface (20c), an outer surface of frusto-conical shape, and a cyclone air outlet (33) communicating with the interior of the cyclone (20) adjacent the upper end of the cyclone (20); a dirt collecting receiver (40) extending from the cone opening (20b); and means for generating an airflow which passes sequentially through the dirty air inlet (27), the container (15), the cyclone air inlet (36), the cyclone (20), the dirt receiver (40) and the cyclone air outlet (33), the airflow rotating around the frusto-conical interior surface (20a) of the cyclone (20) and depositing the dirt in the receiver (40); characterised in that the cleaning apparatus (10) further includes a shroud means (50, 150, 250,) as claimed in any one of the preceding claims.

Claim 15

Cleaning apparatus as claimed in claim 14, wherein the dirt receiver (40) is mounted on the outer surface (20c) of the cyclone (20) and has a conical portion (40d) adjacent the bottom of the container (15) which tapers outwardly towards the sidewall and the bottom of the container (15).

Claim 16

Cleaning apparatus as claimed in claim 15, wherein the dirt receiver (40) has a cyclindrical portion (40c) which extends from an outer edge of a circular plate portion (40a) an inner edge of which contacts the outside surface (20c) of the cyclone (20) adjacent the cone opening (20b) and wherein the cylindrical portion (40c) extends to the conical portion (40d).

Claim 17

Cleaning apparatus as claimed in claim 16, wherein the cylindrical portion (40c) has a diameter smaller than a diameter of the disc means (50h, 150h, 250h).

Claim 18

Cleaning apparatus as claimed in any one of claims 14 to 17, wherein the cleaning apparatus (10) is an upright type vacuum cleaner with a handle (21,22) wherein the airflow generating means is mounted in a casing (12) that supports the container (15), cyclone (20) and dirt receiver (40) and wherein the floor engaging cleaner head (11) contacts a surface to be cleaned and an airflow control cover is mounted on an open end of the container (15) for directing airflow of dirt-laden air into the container (15) and for directing airflow out of the outlet (33) from the cyclone (20).

Claim 19

Cleaning apparatus as claimed in claim 18, wherein separate tubes (30,34) are mounted on the outside of the container (15) parallel to the longitudinal axis of the container (15) and wherein the separate tubes (30,34) are on opposed sides of and in a closely spaced relationship to the handle (21,22), said tubes (30,34) being in air flow communication with the cover (12) so that, in use, one tube (30) serves as a dirty air inlet to the container (15) and wherein clean air from the cyclone (20) is removed through the other tube (34) and is used to cool the air flow generating means.