Drive coupling for high-speed rotating brush

{
  "publication_number": "US2014150191A1",
  "country": "US",
  "kind": "A1",
  "title": "Drive coupling for high-speed rotating brush",
  "abstract": "Drive coupling assembly (50) for a high-speed rotating brush, comprising: - a coupling head (100) having a coupling head rotation axis (L ch) and including three drive surfaces (106) which are arranged to be rotationally symmetrical through 120° with respect to said coupling head rotation axis; and - a coupling member (200), having a coupling member rotation axis (L cm) and including three first drive surfaces (210 a) which are arranged to be rotationally symmetrical through 120° with respect to said coupling member rotation axis, wherein said coupling head (100) and said coupling member (200) are detachably couplable, such that, in a coupled condition, their rotational axes (L ch, L cm) are aligned and the coupling head is rotatable to drive each of its drive surfaces (106) in contact with a respective first drive surface (210 a) of the coupling member, to thereby exert both a torque and an axially directed force on the coupling member.",
  "claims": [
    "1. A drive coupling assembly for a high-speed rotating brush, comprising: a coupling head having a coupling head rotation axis (L ch) and including three drive surfaces which are arranged to be rotationally symmetrical through 120° with respect to said coupling head rotation axis; and a coupling member, having a coupling member rotation axis (L cm) and including three first, helicoidal drive surfaces which are arranged to be rotationally symmetrical through 120° with respect to said coupling member rotation axis, characterized in that the coupling member further includes three second drive surfaces, each of which second drive surfaces is mirror symmetric to a respective first drive surface in a respective axial-radial plane of symmetry (P), and in that said coupling head and said coupling member are detachably couplable, such that, in a coupled condition, their rotational axes (L ch, L cm) are aligned and the coupling head is rotatable to drive each of its drive surfaces in contact with a respective first or second drive surface of the coupling member, wherein the drive surfaces of the coupling head and the first and second drive surfaces of the coupling member are configured such that rotatably driving the former in contact with the latter results in the exertion of both a torque and an axially directed force on the coupling member, which axially directed force is independent of whether the coupling member is driven clockwise or counter-clockwise with respect to its rotation axis L cm). 2. (canceled) 3. The drive coupling assembly according to claim 1, wherein each of the first drive surfaces of the coupling member defines a helicoid whose axis substantially coincides with the coupling member rotation axis (L cm). 4. The drive coupling assembly according to claim 3, wherein each of the first drive surfaces of the coupling member defines a right open helicoid. 5. The drive coupling assembly according to 4, wherein the drive surfaces of the coupling head and the coupling member have a radial extent ≦15 mm, and preferably 9 mm. 6. (canceled) 7. The drive coupling assembly according to claim 4, wherein the coupling member defines a coupling head reception cavity, said cavity being bounded by a side wall that extends around the coupling member rotation axis (L cm), and that provides for three radially inwardly protruding drive cams, each of which drive cams provides for a first drive surface. 8. The drive coupling assembly according to claim 7, wherein each drive cam, seen in a tangential direction with respect to the coupling member rotation axis (L cm), provides for a leading first drive surface, and a trailing second drive surface. 9. The drive coupling assembly according to claim 7, wherein the coupling head reception cavity is further bounded by a generally planar back wall that extends perpendicular to the coupling member rotation axis (L cm), and that connects to the side wall. 10. The drive coupling assembly according to claim 9, wherein the coupling head includes a generally triangular drive section that provides for the coupling head's drive surfaces, which are interconnected by connecting surfaces. 11. The drive coupling assembly according to claim 10, wherein each of the drive surfaces of the coupling head, seen in a plane perpendicular to the coupling head rotation axis (L ch), includes a slight convex curvature. 12. The drive coupling assembly according to claim 11, wherein each of the drive surfaces of the coupling head, seen in a plane substantially transverse to a respective drive surface and containing the coupling head rotation axis (L ch), has a convex curvature whose center of lies substantially on the coupling head rotation axis (L ch). 13. The drive coupling assembly according to claim 9, wherein the back wall of the coupling head reception cavity includes a central opening or recess, and wherein the coupling head comprises a central nose that protrudes axially from the drive section, said opening or recess being configured to receive the nose in the coupled condition of the coupling head and the coupling member. 14. A high-speed rotating brush assembly for a floor cleaning device, comprising an elongate, substantially cylindrical brush, extending between a first end and a second end, and configured to be rotatably mounted at said ends in a floor cleaning device, wherein one of said ends is provided with either a coupling head or a coupling member of a drive coupling assembly according to claim 1. 15. A floor cleaning device, comprising: an elongate, substantially cylindrical brush that is rotatably mounted around its longitudinal axis; a motor mechanism configured to drive the brush into rotation at a rotational speed of at least 2500 rpm; and a drive coupling assembly according to claim 1, disposed in between the motor mechanism and the brush, such that, during operation, a torque generated by the motor mechanism is transferred onto said brush via said drive coupling assembly, together with a force directed along the longitudinal axis of the brush."
  ],
  "description_excerpt": "The present invention relates to the field of hard floor cleaning devices, and more in particular to a drive coupling for a high-speed rotating brush of such a cleaning device.\n\nA hard floor cleaning device may include one or more high-speed rotating brushes. Each brush may have an elongate cylindrical core, extending axially between a first end and a second end, whose outer surface is covered with a brush material, e.g. soft microfiber filaments. The first and second ends of the brush may be bearingly mounted in the cleaning device so as to enable rotation of the brush around its axis, in particular when the latter is oriented parallel to and in abutment with a floor to be cleaned. The brush may typically be rotationally driven from one of its bearingly mounted ends, for which purpose the respective end may be detachably coupled to a transmission of an (electro)motor by means of a drive coupling assembly. The manner in which a brush is bearingly mounted in the hard floor cleaning device and coupled to the transmission may significantly effect its operating behavior. For instance, it is known to mount a low-speed rotating brush, configured to be driven at a rotational speed of about 1,500 rpm, in a hard floor cleaning device by means of a drive coupling that includes an axial spring mechanism. The axial spring mechanism serves to take up axial play between the ends of the brush and brush mounting points of the cleaning device and to fix the brush's axial position between these mounting points (i.e. prevent travel of the brush through its range of axial play).",
  "cpc": [
    "F16D 1/108",
    "A47L 11/4069",
    "F16B 2200/10",
    "F16D 1/10",
    "F16D 1/101",
    "F16D 2001/102"
  ],
  "ipc": [
    "A47L 11/40",
    "F16D 1/108"
  ],
  "assignees": [
    "DE WIT BASTIAAN JOHANNES",
    "WIERDA WIEBE",
    "VOORHORST FOKKE ROELOF",
    "KONINKL PHILIPS NV"
  ],
  "inventors": [
    "DE WIT BASTIAAN JOHANNES",
    "WIERDA WIEBE",
    "VOORHORST FOKKE ROELOF"
  ],
  "filing_date": "2012-07-27",
  "publication_date": "2014-06-05",
  "priority_date": "2011-08-11",
  "application_number": "US-201214236251-A",
  "family_id": "44719247",
  "citations": [
    "US2008025788A1",
    "US4150590A",
    "US5165140A",
    "US6768890B2"
  ]
}