Some Examples of Polymer Selection

Abstract

This unit serves a dual purpose on a vacuum cleaner. Its parts are shown in Fig. 3.1, and it is assembled as follows. The bristles in their metal retaining ring pass over the annular section ‘A’. The protection ring goes inside the ring of bristles to locate an annular section ‘B’. The ‘ears’ locate their pins ‘C’ in holes ‘D’; in this position they can rotate. In operation, the unit can be used either as a brush-assisted dusting tool or as a small upholstery cleaning tool. For dusting, the vacuum pipe from the cleaner cylinder is pushed into a suitable socket at ‘E’. The ‘ears’ are folded flat against the pipe, parallel to each other, and perpendicular to edge D1-D1. For upholstery cleaning the ears are turned through 90° to be horizontally opposed to one another to form a typical small suction tool. The vacuum pipe is now inserted through the centre brush.