Synchronizing mechanism

Abstract

An office chair has a base support, a seat support and a backrest support. A synchronizing mechanism for a correlated seat/backrest movement has the seat support articulated directly on a first pivot bearing of the base support, the backrest support articulated directly on a second pivot bearing of the base support, and the backrest support connected to the seat support via an articulation. The articulation axis of the articulation, as seen in the longitudinal direction of the seat, is in front of the pivot axis of the second pivot bearing, such that a pivoting movement of the backrest to the rear about the pivot axis of the second pivot bearing induces a rotation of the seat support about the pivot axis of the first pivot bearing and thus a lifting movement of just the front region of the seat support.

1 - 4 . (canceled) 
     
     
         5 . A synchronizing mechanism for a correlated seat/backrest movement of an office chair, the chair having a base support to be placed on a chair column, a seat support and a backrest support, the synchronizing mechanism comprising:
 a first pivot bearing disposed on the base support, said first pivot bearing having a first pivot axis and directly articulating the seat support;   a second pivot bearing disposed on said base support, said second pivot bearing having a second pivot axis and directly articulating the backrest support;   an articulation connecting the backrest support to the seat support; and   said articulation having an articulation axis disposed, as seen in a longitudinal direction of the seat support, in front of said second pivot axis of said second pivot bearing, such that a pivoting movement of the backrest to a rear about said second pivot axis induces a rotation of the seat support about said first pivot axis of said first pivot bearing and a lifting movement of a forward region of the seat support.   
     
     
         6 . The synchronizing mechanism according to  claim 5 , wherein said articulation connects the backrest support directly to the seat support. 
     
     
         7 . The synchronizing mechanism according to  claim 5 , wherein said articulation is a rotary sliding articulation. 
     
     
         8 . The synchronizing mechanism according to  claim 5 , wherein said first pivot bearing is disposed at a rear end of the base support. 
     
     
         9 . An office chair with a synchronizing mechanism for a correlated seat/backrest movement, the office chair comprising:
 a base support to be placed on a chair column, a seat support and a backrest support;   wherein said seat support is articulated directly on a first pivot bearing of said base support;   wherein said backrest support is articulated directly on a second pivot bearing of said base support;   an articulation connecting said backrest support to said seat support, said articulation having an articulation axis disposed in front of said pivot axis of said second pivot bearing, in a longitudinal direction of said seat support, such that a rearward pivoting movement of said backrest about said pivot axis of the second pivot bearing induces a rotation of said seat support about said pivot axis of said first pivot bearing with a lifting movement of a forward region of said seat support.