GB1037702A - Improvements in or relating to a supporting base for chair and the like - Google Patents

Abstract

1,037,702. Seats. DENTISTS SUPPLY CO. OF NEW YORK. April 24, 1964 [April 25, 1963], No. 17183/64. Heading A4J. [Also in Division B7] A mobile support for a chair seat 18 comprises a base 10 suspended upon a film of air so as to be readily movable. The base 10 is provided with an air inlet 140 communicating with an annular chamber 142 in which an air compressor 144 is mounted. The compressor is driven by an electric motor 148 which can be turned on and off by a switch 218. The chamber 142 communicates with an annular distribution chamber 158 formed by the peripheral flange 12 of the base and concentric annular walls 160, 162 connected by an annular plate 164. Air under pressure is discharged through spaced openings 166 in the plate 164 to inflate a sealing member 168 of porous flexible material attached to the periphery of the flange 12. Air is discharged through the pores of the sealing member 168, a thin film of air being formed between the member 168 and the floor. The annular plate 164 may extend beyond the periphery of the flange 12 and be downwardly bent to form a grinding flange 198 covered by a material having a low coefficient of friction with the floor surface. Instead of using compressor 144, air under pressure may be supplied from an external source and conducted to the chamber 158 through a control valve. The chair 18 is vertically not non-rotatably adjustable with respect to the base 10. The chair is mounted in a header 16 having dependent vertical guide rods 20 movable through guides 22 in the base. The header is moved vertically by a reversible electric motor 40 which rotates a sleeve 28 provided with a ball-nut 26 which rotates on a screw shaft 24 of the header 16. A double throw switch controls the motor 40. When the motor is switched off a brake and clutch mechanism operates to prevent further rotation of the shaft 28.