Robotic vacuum cleaning system

Patent metadata

Field	Value
Publication number	US-9320400-B2
Application number	US-201414588077-A
Country	US
Kind code	B2
Filing date	Dec 31, 2014
Priority date	Apr 29, 2011
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

An autonomous coverage robot includes a cleaning assembly having forward roller and rearward rollers counter-rotating with respect to each other. The rollers are arranged to substantially maintain a cross sectional area between the two rollers yet permitting collapsing therebetween as large debris is passed. Each roller includes a resilient elastomer outer tube and a partially air-occupied inner resilient core configured to bias the outer tube to rebound. The core includes a hub and resilient spokes extending between the inner surface of the outer tube and the hub. The spokes suspend the outer tube to float about the hub and transfer torque from the hub to the outer tube while allowing the outer tube to momentarily deform or move offset from the hub during impact with debris larger than the cross sectional area between the two rollers.

First claim

What is claimed is:

1. An autonomous coverage robot comprising:
a chassis having forward and rearward portions;
a drive system supported by the chassis and configured to maneuver the robot over a cleaning surface; and
a cleaning assembly supported by the chassis, the cleaning assembly comprising:
a roller housing;
a first roller rotatably mounted to the roller housing and defining a first longitudinal axis, the first roller being rotatable about the first longitudinal axis in a first direction; and
a second roller rotatably mounted to the roller housing rearward of and substantially parallel to the first roller, the second roller defining a second longitudinal axis and being rotatable about the second longitudinal axis in a second direction opposite of the first direction;
wherein the second roller is spaced from the first roller to form an air gap therebetween; and
wherein the first and second rollers are each resiliently compressible to allow passage of an object having a dimension larger than the air gap between the first and second rollers when the first and second rollers are counter-rotating in the respective first and second directions.

2. The autonomous coverage robot of claim 1 , further comprising:
an enclosed dust bin defining a collection volume; and
a sealed vacuum plenum pneumatically connecting the cleaning assembly to the collection volume.

3. The autonomous coverage robot of claim 2 , wherein the sealed vacuum plenum defines a first opening positioned above the first and second rollers and a second opening positioned at an entry to the collection volume.

4. The autonomous coverage robot of claim 3 , wherein a portion of the sealed vacuum plenum defines a deflecting slope above the air gap that redirects debris toward the collection volume, the deflecting slope having an angle of less than 90 degrees relative to a vertical axis defined with respect to the cleaning surface.

5. The autonomous coverage robot of claim 4 , wherein the deflecting slope of the sealed vacuum plenum comprises a rigid material adjoined to a remainder of the sealed vacuum plenum at a sealed elastomeric overmolded joint.

6. The autonomous coverage robot of claim 5 , wherein the elastomeric overmolded joint is downstream from the deflecting slope and has a downward slope in an operating position.

7. The autonomous coverage robot of claim 6 , wherein the sealed vacuum plenum comprises a substantially horizontal elastomeric portion leading to the entry of the collection volume, the substantially horizontal elastomeric portion being configured to flex with movement of the cleaning assembly with respect to the chassis.

8. The autonomous coverage robot of claim 7 , wherein the substantially horizontal elastomeric portion flexes at least about 4 mm to about 6 mm in a vertical direction along the vertical axis.

9. The autonomous coverage robot of claim 1 , wherein the roller housing surrounds between about 125 degrees and about 175 degrees of an outer circumferential periphery of each of the first and second rollers.

10. The autonomous coverage robot of claim 1 , wherein the roller housing is spaced from a radially outermost part of each of the first and second rollers by less than or equal to about 1 mm.

11. The autonomous coverage robot of claim 1 , wherein the cleaning assembly further comprises a cleaning head frame, the cleaning head frame defining a portion of the chassis to which the roller housing is movably linked or being immovably attached to the chassis to which the roller housing is movably linked.

12. The autonomous coverage robot of claim 1 , wherein the cleaning assembly is movably mounted to the chassis by a linkage having a forward end and a rearward end, and being affixed at the forward end to the chassis and at the rearward end to the cleaning assembly housing, the linkage being configured to lift the cleaning assembly from the cleaning surface.

13. The autonomous coverage robot of claim 12 , wherein the linkage is configured to lift the cleaning assembly substantially parallel to the cleaning surface such that the first roller lifts at a faster rate than the second roller.

14. The autonomous coverage robot of claim 12 , wherein the linkage is configured to lift the cleaning assembly at a variable rate such that a maximum lift angle from a resting state is less than about 10°.

15. The autonomous coverage robot of claim 12 , wherein the linkage comprises a four-bar linkage symmetrically placed about the cleaning assembly such that a forward end of each bar of the four-bar linkage attaches to the cleaning assembly at or near a forward edge of the cleaning assembly.

16. The autonomous coverage robot of claim 1 , wherein each roller comprises:
a resilient shape-changing tube having a circumferential wall; and
a plurality of agitator vanes extending outwardly along the circumferential wall to agitate and direct debris from the cleaning surface through the air gap, the agitator vanes extending into the air gap.

17. The autonomous coverage robot of claim 16 , wherein the agitator vanes of the first and second rollers are non-overlapping in the air gap.

18. The autonomous coverage robot of claim 16 , wherein the resilient shape-changing tube of at least one of the rollers partially deforms in cross section from a circular cross-sectional shape to an altered cross-sectional shape when the object passes between the first and second rollers.

19. The autonomous coverage robot of claim 1 , wherein the first and second rollers are each resiliently compressible toward the respective first and second longitudinal axes.

20. The autonomous coverage robot of claim 1 , wherein the first roller is positioned higher than the second roller such that, on a firm cleaning surface, the first roller suspends above the surface and only the second roller makes contact with the firm cleaning surface.

21. The autonomous coverage robot of claim 1 , wherein a narrowest portion of the air gap has a width of between about 1 mm and about 2 mm.

22. The autonomous coverage robot of claim 1 , wherein the cleaning assembly is mounted on the forward portion of the chassis.

Assignees

• Irobot Corp

Inventors

• Gilbert Jr Duane L
• Bursal Faruk Halil
• Therrien Richard Joseph
• Morin Russell Walter

Classifications

• A47L11/4061

  Steering means; Means for avoiding obstacles; Details related to the place where the driver is accommodated · CPC title

• A47L9/2821

  Pressure, vacuum level or airflow · CPC title

• A47L11/4041 Primary

  Roll shaped surface treating tools · CPC title

• A47L11/4013

  Contaminants collecting devices, i.e. hoppers, tanks or the like · CPC title

• A47L9/04 Primary

  with driven brushes or agitators · CPC title