Autonomous surface treating appliance

Abstract

An autonomous surface treating appliance comprising a chassis having a drive arrangement and a control system interfaced to the drive arrangement so as enable control of the appliance across a surface to be treated, wherein the drive arrangement comprises at least one traction unit, each traction unit comprising a surface-engaging track constrained around a leading wheel and a trailing wheel, the leading wheel and the trailing wheel being arranged so that a track portion opposing the floor surface and extending between the leading and trailing wheels defines a ramped climbing surface.

1 . An autonomous surface treating appliance comprising a chassis having a drive arrangement and a control system operatively connected to the drive arrangement so as enable control of the appliance across a surface to be treated, wherein the drive arrangement comprises at least one traction unit, the at least one traction unit comprising a surface-engaging track constrained around a leading wheel and a trailing wheel so as to define a track portion extending between the leading and trailing wheels that opposes a floor surface, the leading wheel and the trailing wheel being arranged so that the track portion defines a ramped climbing surface. 
     
     
         2 . The appliance of  claim 1 , wherein the traction unit includes a single trailing wheel. 
     
     
         3 . The appliance of  claim 1 , wherein the trailing wheel has a greater diameter than that of the leading wheel. 
     
     
         4 . The appliance of  claim 1 , wherein the drive arrangement includes a motor to drive the leading wheel in response to commands from the control system. 
     
     
         5 . The appliance of  claim 4 , wherein the motor is a brushless DC electric motor. 
     
     
         6 . The appliance of  claim 4 , wherein the at least one traction unit further comprises a transmission unit extending between the motor and the leading wheel. 
     
     
         7 . The appliance of  claim 6 , wherein the trailing wheel is mounted to a first end of a linkage member and wherein a second end of the linkage member is pivotable about an axis of the leading wheel. 
     
     
         8 . The appliance of  claim 7 , wherein the linkage member includes a guard member that at least partially fills a volume bounded by the leading wheel, the trailing wheel and the track. 
     
     
         9 . The appliance of  claim 7 , wherein the linkage member is pivotably mounted to the transmission unit about the leading wheel axis, and wherein the transmission unit is mounted to the chassis. 
     
     
         10 . The appliance of  claim 9 , wherein a biasing element is provided between the transmission unit and the linkage member so as to urge the trailing wheel into contact with the surface to be treated. 
     
     
         11 . The appliance of  claim 1 , wherein the trailing wheel includes a track engaging face and a rim portion adjacent to and having a greater diameter than the track engaging surface. 
     
     
         12 . The appliance of  claim 11 , wherein the rim portion extends to the same radial position as the outer surface of the track. 
     
     
         13 . The appliance of  claim 11 , wherein the rim portion has a serrated profile. 
     
     
         14 . The appliance of  claim 1 , further comprising an airflow generator for generating a flow of air between a dirty air inlet and a clean air outlet, and a separating apparatus disposed in the airflow path between the dirty air inlet and the clean air outlet so as to separate dirt from the airflow. 
     
     
         15 . The appliance of  claim 1 , wherein the chassis includes a supporting arrangement that bear the chassis on a floor surface in a generally parallel orientation. 
     
     
         16 . The appliance of  claim 15 , wherein the supporting arrangement includes wheels, rollers or skids. 
     
     
         17 . The appliance of  claim 1 , wherein the trailing wheel is mounted to a first end of a linkage member and wherein a second end of the linkage member is pivotable about an axis of the leading wheel.