Patent ID: 8272692

Claim:
An office chair having tiltable seat and backrest members, comprising: a support module; a seat carrier supported by said support module; a seat member articulated to said seat carrier such as by being pivotal along a front end of said seat member, said seat member having a first initial position of being forwardly declined; a backrest carrier having a backrest member, said backrest carrier articulated to said seat carrier such as by being pivotal along a lower end of said backrest carrier, said backrest carrier and said backrest member having a second initial position of being rearwardly angled; an actuator arm directly linking said seat member to said backrest carrier; and a spring arrangement connected to said backrest carrier to return said backrest carrier and thus said seat member via said actuator arm to said first and second initial positions when a weighted load is lessened or removed from a rear end of said seat member, wherein said spring arrangement has an adjustment mechanism.