Reducing cleaning roller amplitude and speed oscillations of a cleaning robot

Patent metadata

Field	Value
Publication number	US-2020352402-A1
Application number	US-202016871149-A
Country	US
Kind code	A1
Filing date	May 11, 2020
Priority date	May 10, 2019
Publication date	Nov 12, 2020
Grant date	—

Abstract

A roller assembly for a mobile cleaning system for cleaning a work surface can include a drive shaft, a sheath, a bushing, and a bushing shroud. The drive shaft can be rotatable about a drive axis, and the drive shaft can include a driven end and an opposite bushing end. The sheath can be supported by the drive shaft and the sheath can be rotatable with the drive shaft. The sheath can include a shell engageable with the work surface. The bushing can be located about the bushing end of the drive shaft. The bushing shroud can be connected to the bushing. The sheath and the drive shaft can be together rotatable with respect to the bushing and the bushing shroud, the bushing shroud can include an outer portion defining a first radius of curvature and a recessed portion connected to the outer portion.

First claim

1 . A roller assembly for a mobile cleaning system for cleaning a work surface, the roller assembly comprising:
a drive shaft rotatable about a drive axis, the drive shaft including a driven end and an opposite bushing end; a sheath supported by the drive shaft, the sheath rotatable with the drive shaft, and the sheath including a shell engageable with the work surface; a bushing located about the bushing end of the drive shaft; and a bushing shroud connected to the bushing, the sheath and the drive shaft together rotatable with respect to the bushing and the bushing shroud, the bushing shroud defining a periphery including:
an outer portion defining a first radius of curvature; and
a recessed portion connected to the outer portion and defining a second radius of curvature different from the first radius of curvature.

2 . The roller assembly of claim 1 , wherein the recessed portion of the periphery defines a clearance to permit a portion of the sheath to deflect radially inward when the sheath contacts the working surface.

3 . The roller assembly of claim 2 , wherein the recessed portion of the periphery provides a clearance to permit a portion of the sheath to deflect radially inward of an outer diameter of the outer portion.

4 . The roller assembly of claim 3 , wherein the shroud is located axially within the shell of the sheath.

5 . The roller assembly of claim 1 , wherein the recessed portion defines a concavity.

6 . The roller assembly of claim 1 , wherein the periphery of the bushing shroud has a geometric shape of a polygonal cylinder or a polygonal cylinder with rounded corners and chords.

7 . A roller assembly for a mobile cleaning system for cleaning a work surface, the roller assembly comprising:
a drive shaft rotatable about a drive axis, the drive shaft drivable from a driven end; a sheath supported by the drive shaft and rotatable therewith, the sheath including a shell engageable with the work surface; a bushing connected to a bushing end of the drive shaft; and a bushing shroud connected to the bushing, the sheath and the drive shaft together rotatable with respect to the bushing and the bushing shroud, the bushing shroud defining a periphery including:
an outer portion; and
a recessed portion connected to the outer portion, at least a portion of the recessed portion terminating radially inward of the outer portion, and the recessed portion configured to allow the sheath to deflect radially inward of the outer portion.

8 . The roller assembly of claim 7 , wherein the recessed portion is a flat portion of the bushing shroud.

9 . The roller assembly of claim 8 , wherein the flat portion of the periphery defines a planar outer surface.

10 . The roller assembly of claim 8 , wherein the recessed portion of the periphery is defined by a chord of a circular projection outline defined by the outer portion.

11 . The roller assembly of claim 8 , wherein the flat portion of the periphery defines a planar outer surface.

12 . The roller assembly of claim 7 , wherein a radially outer portion of the periphery terminates radially inward of the shell and wherein the recessed portion of the periphery defines a nadir that is radially inward of the radially outer portion of the periphery.

13 . The roller assembly of claim 7 , further comprising:
a bushing bracket supporting the bushing shroud; and a bushing shroud mount including a flat, the flat engageable with the bracket to orient the recessed portion of the periphery toward the working surface.

14 . The roller assembly of claim 13 , wherein the bushing shroud includes a plurality of recessed portions terminating radially inward of the outer portion of the periphery, and wherein the bushing shroud mount includes a plurality of flats, each flat engageable with the mount to orient one of the recessed portions of the plurality of recessed portions of the periphery toward the working surface.

15 . The roller assembly of claim 14 , wherein the shroud is located axially within the shell of the sheath.

16 . The roller assembly of claim 15 , wherein the bushing shroud mount extends axially beyond a bushing end of the sheath.

17 . A roller assembly for a mobile cleaning system for cleaning a work surface, the roller assembly comprising:
a drive shaft extending longitudinally along and rotatable about a drive axis; a sheath supported by the drive shaft, the sheath rotatable with the drive shaft, and the sheath engageable with the work surface; a bushing connected to the drive shaft; and a bushing shroud connected to the bushing, the sheath and the drive shaft together rotatable with respect to the bushing and the bushing shroud, the bushing shroud defining a periphery including:
an outer portion defining a first radius of curvature; and
a recessed portion connected to the outer portion and defining a concavity.

18 . The roller assembly of claim 17 , wherein the recessed portion of the periphery defines a clearance to permit a portion of the sheath to deflect radially inward when the sheath contacts the working surface.

19 . The roller assembly of claim 18 , wherein the recessed portion of the periphery provides a clearance to permit a portion of the sheath to deflect radially inward of an outer diameter of the outer portion.

20 . The roller assembly of claim 19 , wherein the shroud is located axially within a shell of the sheath.

Assignees

• Irobot Corp

Inventors

• Chow Hao-Yun
• Chow Patrick
• Gao Ke Ting
• Guo Fangzheng
• Mauger Jennifer Ann
• Neumann Rogelio Manfred
• Pi Jian Yun
• Sack Michael G
• Verma Rubal

Classifications

• F16C2314/00

  Personal or domestic articles, e.g. household appliances such as washing machines, dryers · CPC title

• F16C35/02

  in the case of sliding-contact bearings · CPC title

• F16C27/02

  Sliding-contact bearings · CPC title

• F16C13/006

  Guiding rollers, wheels or the like, formed by or on the outer element of a single bearing or bearing unit, e.g. two adjacent bearings, whose ratio of length to diameter is generally less than one · CPC title

• A47L9/0477

  Rolls · CPC title