Patent ID: 6895709

Claim:
Apparatus comprising: a substantially cylindrical shaft having a longitudinal axis, the shaft having an upper end and a lower end; a base mounted to the shaft at the lower end, the base being arranged to position the longitudinal axis to a generally vertical orientation; a platform removably attached to the upper end of the shaft; a first collar slidably assembled to the shaft intermediate the base and the upper end; at least one seat assembly supported by the first collar, the seat assembly including: a seat arm supported by the first collar, and a seat supported by the seat arm distal from the first collar; a plurality of pin-receiving apertures in the shaft spaced along the longitudinal axis; and a pin receivable in a selected pin-receiving aperture to support the first collar at a selected location along the longitudinal axis so that the first collar is freely rotatable about the axis; and wherein the first collar includes a first bearing portion and the apparatus further includes: a bearing member coupled to the shaft by the pin, and a second bearing portion on the bearing member and journaled to the first bearing portion so that the seat assembly can rotate in the longitudinal axis.