Rotatable seat

Abstract

A rotatable seat mounted on a floor includes a seat proper, a lower base member mounted on the floor, an upper base member mounting thereon the seat proper and a retaining member for retaining the upper base member on the lower base member. The lower base member has a first annular portion. The upper base member has an annular flange portion and a second annular portion which is truncated conical in shape. The annular flange portion is rotatably put on the first annular portion such that the upper base member is rotatable relative to the lower base member. The retaining member is secured to the lower base member and has third and fourth annular portions. The third annular portion is opposed to and spaced from the first annular portion such that an annular groove for receiving therein the annular flange portion is defined therebetween. The fourth annular portion is truncated conical in shape and opposed to and spaced from the second annular portion such that a certain clearance is provided therebetween and that, when the upper base member receives a force to separate the upper base member from the lower base member, deformation of the upper base member is substantially suppressed by that the second annular portion is brought into abutment with the fourth annular portion.