Chair having flection adjustment module for lumbar support part

Abstract

Provided is a chair having a flection adjustment module for a lumbar support part, and more particularly, to a chair having a flection adjustment module for a lumbar support part, the chair including: a seat part; a support part coupled to the seat part; a backrest part coupled to an upper end of the support part so as to be disposed on an upper portion of the seat part, extending downward from the upper end of the support part, and including a lumbar support part bent corresponding to a waist portion of a user; and a flection adjustment module movably coupled between the backrest part and the support part to adjust flection of the lumbar support part.

What is claimed is: 
     
         1 . A chair having a flection adjustment module for a lumbar support part, the chair comprising:
 a seat part;   a support part ( 200 ) coupled to the seat part;   a backrest part coupled to an upper end of the support part so as to be disposed on an upper portion of the seat part, extending downward from the upper end of the support part, and including a lumbar support part bent corresponding to a waist portion of a user; and   a flection adjustment module movably coupled between the backrest part and the support part to adjust flection of the lumbar support part,   wherein the flection adjustment module includes:
 a connection member coupled to the backrest part and having a length extending toward the support part; 
 a latching member mounted in the connection member to perform a pendular movement, and having a pin protruding toward the support part; 
 an elastic member mounted on both sides of the latching member to allow the pendular movement to be elastically performed; and 
 a step adjustment member coupled to the support part, and formed on a rear surface thereof with a step adjustment groove including one or more latching grooves in which the pin is inserted and seated, 
   the latching grooves are obliquely formed in a longitudinal direction of the step adjustment member,   the latching member is mounted in a protrusion groove formed in an upper center of one surface of the connection member, and   the elastic member is mounted in an elastic member coupling groove obliquely formed on both lower sides of the connection member.   
     
     
         2 . The chair of  claim 1 , wherein the flection adjustment module is fixedly coupled to the backrest part while being coupled to the support part so as to be vertically movable. 
     
     
         3 . The chair of  claim 1 , wherein the step adjustment member further includes a pin guide groove for guiding a movement of the pin along an outer periphery of the step adjustment groove. 
     
     
         4 . The chair of  claim 1 , wherein an insertion part of the latching groove into which the pin is inserted is formed at a position higher than a position of a seating part of the latching groove at which the pin is stopped. 
     
     
         5 . The chair of  claim 1 , wherein an upper surface of each of the latching grooves has a streamline shape. 
     
     
         6 . The chair of  claim 1 , wherein the latching grooves are formed on one side of the step adjustment groove in parallel to each other. 
     
     
         7 . The chair of  claim 1 , wherein the flection adjustment module further includes a cover member coupled to the connection member to cover the one surface of the connection member, and having a fluctuation groove corresponding to a fluctuation radius of the pin. 
     
     
         8 . The chair of  claim 1 , wherein the step adjustment member further includes a connection member guide groove formed on both sides of the step adjustment groove to guide a movement of the connection member, and
 the connection member has a protrusion part having a shape corresponding to the connection member guide groove.