Central unit for a chair

Abstract

A central unit for a chair, in particular an office chair, has a multi-joint body that is formed of a seat part for a seat, a backrest part for a backrest, a support part for a support of a base and a front part arranged between the seat part and the support part, wherein the multi-joint body comprises at least three joints, which in each case connect two of the specified parts in an articulated manner.

What is claimed is: 
     
         1 . A central unit for a chair, comprising a multi-joint body that comprises:
 a seat part configured for connection to a seat,   a backrest part configured for connection to a backrest,   a support part configured for connection to a support of a base, and   a front part arranged between the seat part and the support part,   wherein the multi-joint body comprises at least three joints which each connect two of the specified parts in an articulated manner.   
     
     
         2 . The central unit according to  claim 1 , wherein at least one of the joints is a solid-body joint. 
     
     
         3 . The central unit, according to  claim 2 , wherein the at least one solid-body joint is formed in one piece with the parts connected by the at least one solid-body joint. 
     
     
         4 . The central unit according to  claim 1 , wherein the multi-joint body is formed in one piece. 
     
     
         5 . The central unit according to  claim 1 , wherein the multi-joint body is made of plastics material. 
     
     
         6 . The central unit according to  claim 1 , wherein exactly one of the joints is designed as a hinge with a rotation pin. 
     
     
         7 . The central unit according to  claim 1 , wherein the front part is designed to be flexurally elastic. 
     
     
         8 . The central unit according to  claim 1 , wherein a spring arrangement is arranged between the seat part and the support part. 
     
     
         9 . The central unit according to  claim 8 , wherein the spring arrangement comprises at least one spring element that is configured to be activated and deactivated or attached to the multi-joint body. 
     
     
         10 . The central unit according to  claim 1 , wherein a limiting arrangement is provided for limiting a maximum relative movement of the seat part and the backrest part. 
     
     
         11 . The central unit according to  claim 1 , wherein a manually operable locking mechanism is provided for locking a relative position of the seat part and the backrest part. 
     
     
         12 . The central unit according to  claim 1 , wherein a manually operable seat tilt limiter is provided. 
     
     
         13 . The central unit according to  claim 1 , wherein a pin is arranged on the backrest part, which pin is guided in a slot of a guide part arranged on the support part. 
     
     
         14 . The central unit according to  claim 13 , wherein a latch is pivotably arranged on the guide part and comprises both a stop for the pin and a locking receptacle for the pin. 
     
     
         15 . The central unit according to  claim 2 , wherein the at least three joints are solid-body joints. 
     
     
         16 . The central unit according to  claim 15 , wherein the at least three joints consist of exactly three joints, all of which are solid-body joints, and wherein the front part is flexurally elastic. 
     
     
         17 . The central unit according to  claim 15 , wherein the at least three joints consist of exactly four joints, all of which are solid-body joints. 
     
     
         18 . A chair having the central unit according to  claim 1 .