Abstract: A robotic cleaning appliance includes a housing to which is coupled a surface treatment item and a sensor assembly with first and second transducers and an acoustic interface. The first sonic transducer transmits sonic signals through an acoustic interface and out of a first acoustic opening toward a surface beneath the robotic cleaning appliance. The sonic signals reflect from the surface as corresponding returned signals received by the second sonic transducer via a second acoustic opening port of the acoustic interface. A first annular ring is defined around the first acoustic opening port and a second annular rings is defined around the second acoustic opening port. The annular ring attenuate direct path echoes between the acoustic opening ports. The first and second acoustic opening ports are coupled the first and sonic transducers, respectively, via first and second horns; and the horns are tilted from orthogonal with the surface.

Abstract: A robotic cleaning appliance includes a housing to which is coupled a surface treatment item and a sensor assembly with first and second transducers and an acoustic interface. The first sonic transducer transmits sonic signals through an acoustic interface and out of a first acoustic opening toward a surface beneath the robotic cleaning appliance. The sonic signals reflect from the surface as corresponding returned signals received by the second sonic transducer via a second acoustic opening port of the acoustic interface. A first plurality of annular rings is defined in the external surface around the first acoustic opening port and a second plurality of annular rings is defined in the external surface around the second acoustic opening port. The pluralities of annular rings attenuate direct path echoes from a subset of the transmitted sonic signals which attempt to travel across the external surface to the second acoustic opening port.

Abstract: The lens of a pair of sunglasses may be quickly replaced in its associated frame by inserting the top portion of the lens within an arcuate-shaped recess of the frame and snap fitting a plurality of dowels carried by the frame into corresponding sockets formed in the lens. Notches provided on opposite sides of each dowel facilitate engagement of the dowel within the recess. A V-shaped nose bridge is also secured to a correspondingly shaped notch in the lens and prevented from removal therefrom by a pair of lugs directed inwardly from opposite edges of the notch. A nose support is secured to the bridge by inserting pegs carried by the bridge into homes formed in the support.

Abstract: An adjustable temple for glasses is to divide the foot of the temple into two separate parts, a foot and an ear hook. The foot includes a C shaped slot at one end having a sinewave shaped portion at bottom edge of the opening end. The ear hook includes a reduced portion integrally formed at one end adopted to insert into the slot of the foot. A rail is formed at one side of the rail adopted to guide the reduced portion to slide in the slot, and a protuberance is formed on the rail to be clamped in the sinewave shaped portion to confine movement of the rail within the slot.