Chair seat tilt adjustment and locking mechanism

• US 5,683,139 A
• Filed: 11/06/1996
• Issued: 11/04/1997
• Est. Priority Date: 01/13/1994
• Status: Expired due to Term

• Current Assignee: Knoll Incorporated (Millerknoll Incorporated)
• Original Assignee: Knoll Incorporated (Millerknoll Incorporated)
• Inventors: Wimmer, Donald A., Golynsky, Arkady
• Primary Examiner(s): Cuomo, Peter M.
• Assistant Examiner(s): BARFIELD, ANTHONY DERRELL
• Application Number:
  US08/744,562
• Time in Patent Office: 363 Days
• Field of Search: 297/300.4, 297/301.3, 297/302.3, 297/302.7, 297/303.3, 297/463.1, 297/463.2, 297/328, 16/2.1, 16/386, 403/66, 403/161
• US Class Current: 297/302.3
• CPC Class Codes: A47C 3/026 with central column, e.g. rocking office chairs; Tilting chairs
• CPC Class Codes: A47C 7/441 with adjustable elasticity
• CPC Class Codes: A47C 7/443 with coil springs
• CPC Class Codes: A47C 7/444 of torsion type
• CPC Class Codes: A47C 7/445 with bar or leaf springs
• CPC Class Codes: Y10T 403/32114 including static joint
• CPC Class Codes: Y10T 403/32951 Transverse pin or stud

Abstract

A chair tilt control mechanism for a pedestal base chair having a chair control housing mounted on the pedestal chair base and pivotally supporting a chair seat support member. A laterally movable front stop member retained within the chair control housing is movable and contacts the front flange of the chair seat support member and limits the pivotal movement of the chair seat support member to predetermined angular positions with respect to the chair control housing and the floor supporting the chair. Also disclosed is a lever member adapted to lock the chair seat support member in one or more predetermined angular positions. Also disclosed is a hollow plastic pivot pin for pivotally connecting a chair control housing to a chair seat support member.

Claims

1. A chair tilt control mechanism for a pedestal base chair comprising:

a chair control housing mounted on a pedestal chair base and supporting a chair seat support member;

a laterally movable front stop member retained within the chair control housing;

a lever mounted to an underside of a chair seat for laterally moving the front stop member;

a connecting link member for laterally moving the front stop member, the connecting link member extending through a bore of one of a pair of hollow pivot pins so that the lateral movement of the front stop member by the connecting link member is conducted through the hollow pivot pin;

each of the hollow pivot pins pivotally connecting the chair control housing to the chair seat support member and comprising a cylindrical tubular plastic member having a circular flange at one end and a pair of pointed, locking snap tabs located on the outer peripheral surface of the tubular plastic member for snap locking the outer periphery of each pin to the chair control housing and chair seat support member.

2. The chair tilt control mechanism according to claim 1 wherein each of the hollow plastic pivot pins includes an opposite end which is camphered.

3. The chair tilt control mechanism according to claim 2 wherein each of the pins further includes a cylindrical tubular metal sleeve secured within and against the diametral surface of the tubular plastic member for retaining and providing a bearing surface for the connecting link member and for strengthening each of the pivot pins.

4. The chair tilt control mechanism according to claim 13 wherein the tubular metal sleeve is retained by portions of each end of the plastic tubular member, the portions extending over ends of the tubular metal sleeve.