Patent ID: 8696064
Filing Date: 2014-04-15
Classification: A47C

Abstract:
1. A backrest inclination structure for lumbar support, comprising: a backrest adjustment mechanism positioned at a chair laterally; a spring continuous control unit disposed at an end of a butterfly-shaped mounting member at a bottom of the chair, wherein the spring continuous control unit guides a link member beside a backrest in performing an unlocking operation or a locking operation; a support-connection portion formed on a rear side of the spring continuous control unit and directionally fixed to a lower end of a support plate with a preset width and extension length; two hollow tubes spaced apart from each other and formed at an upper end of the support plate; a connection tube formed at a rear side and a mass-center position of the backrest, wherein the two hollow tubes straddle the connection tube horizontally; two hollow bodies introduced along the hollow tubes of the support plate, respectively, and positioned in the connection tube of the backrest; a shaft penetrating the two hollow bodies and the connection tube of the backrest and directionally screwed to another end of the connection tube of the backrest with a screw nut, wherein the backrest is pivotally coupled to the support plate; and a torque spring inserted into inward sides of hollow bodies of the two hollow tubes of the support plate, wherein the torque spring has a pin abutting against a rear side of the backrest and another pin abutting against a rear side of the support plate to abut against the backrest; wherein lifting the spring continuous control unit enables the spring continuous control unit to unlock and enter a free state and thereby enables the backrest adjustment mechanism to controllably drive the backrest to perform directional adjustment, wherein the backrest pivotally coupled to the support plate undergoes preset directional adjustment, wherein, pressing the spring continuous control unit allows the spring continuous control unit to return to a locked state and then precisely positions the backrest pivotally coupled to the support plate, wherein, alternatively, lifting the spring continuous control unit enables the spring continuous control unit to enter a free state in a manner that the backrest undergoes seamless displacement.