The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 19, 1983
Filed:
Mar. 18, 1981
Joseph M Wisniewski, Marne, MI (US);
Haworth, Inc., Holland, MI (US);
Abstract
A threaded spindle as fixed to the chair seat is engaged with a nut positioned within the upper end of the base pedestal. A spring urges the nut for engagement with a clutch plate fixed to the pedestal. This clutch plate holds the nut nonrotatable so that when the chair seat is unoccupied and is rotated, the spindle threads through the nut so as to adjust the height of the chair seat. The nut and clutch plate have opposed engageable cam portions which effect automatic disengagement therebetween if the engaged nut and clutch plate are subjected to excessive torsional resistance. When the chair seat is occupied, the nut moves downwardly away from the clutch plate into engagement with a clutch washer which is seated on the pedestal but is nonrotatably keyed to the spindle, whereby the chair seat and the accompanying spindle and nut can freely rotate without causing a height adjustment to occur. A tube is positioned in surrounding relationship to the spindle and its lower end bears on the nut. When the chair seat is adjusted into its lowermost height position, an abutment on the chair seat engages the upper end of the tube.