Back support assembly and chair

Abstract

A back support assembly includes: a back support frame, an elastic support member, a plurality of elastic support rods, and an elastic support sheet. The back support frame has a connection portion. The elastic support member is in a strip shape. Two ends of the elastic support member are connected to the connection portion, and a middle section of the elastic support member is bent towards a direction facing away from the connection portion. One end of each of the plurality of elastic support rods is connected to a side, facing away from the connection portion, of the middle section of the elastic support member, and the other end of the elastic support rod is bent towards a side facing away from the elastic support member and is connected to a back face of the elastic support sheet.

What is claimed is: 
     
         1 . A back support assembly, comprising:
 a back support frame having a connection portion;   an elastic support member in a strip shape, wherein two ends of the elastic support member are connected to the connection portion, and a middle section of the elastic support member is bent towards a direction facing away from the connection portion;   a plurality of elastic support rods arranged at an angle to each other, wherein a first end of each of the plurality of elastic support rods is connected to a first side of the middle section of the elastic support member, the first side being a side, facing away from the connection portion, of the middle section, and each of the plurality of elastic support rods is bent from the first side towards a direction facing away from the elastic support member; and   an elastic support sheet, wherein a second end of each of the plurality of elastic support rods is connected to a back face of the elastic support sheet, and a front face of the elastic support sheet allows a human back to lean against.   
     
     
         2 . The back support assembly according to  claim 1 , wherein the elastic support sheet comprises a skeleton portion and a flexible portion, wherein the flexible portion is arranged around an outer periphery of the skeleton portion, a stiffness of the skeleton portion is greater than a stiffness of the flexible portion, and a second end of the elastic support rod is connected to a back face of the skeleton portion. 
     
     
         3 . The back support assembly according to  claim 2 , wherein the skeleton portion and the flexible portion are made of a same material, and are designed as an integral structure, and a thickness of the skeleton portion is greater than a thickness of the flexible portion, such that the stiffness of the skeleton portion is greater than the stiffness of the flexible portion. 
     
     
         4 . The back support assembly according to  claim 2 , wherein ventilation holes are defined in the flexible portion. 
     
     
         5 . The back support assembly according to  claim 1 , wherein a mesh fabric mounting frame surrounding an outer periphery of the elastic support sheet is arranged on the back support frame, wherein the mesh fabric mounting frame is configured to be connected to an edge of mesh fabric, and the front face of the elastic support sheet is configured to be abutted against the mesh fabric and allow, together with the mesh fabric, the human back to lean against. 
     
     
         6 . The back support assembly according to  claim 5 , wherein the elastic support sheet is in a four-petal shape that is mirror-symmetrical relative to a vertical line of symmetry. 
     
     
         7 . The back support assembly according to  claim 6 , wherein at least three of said elastic support rods are arranged, wherein at least one of the at least three elastic support rods is connected between a back face of a left petal in the elastic support sheet and the middle section of the elastic support member, at least one of the at least three elastic support rods is connected between a back face of a right petal in the elastic support sheet and the middle section of the elastic support member, and at least one of the at least three elastic support rods is connected between a back face of a top petal in the elastic support sheet and the middle section of the elastic support member. 
     
     
         8 . The back support assembly according to  claim 1 , wherein the connection portion comprises a first connection portion and a second connection portion, wherein a first end of the elastic support member is rotatably connected to the first connection portion, a second end of the elastic support member is slidably connected to the second connection portion along an extension direction of the elastic support member, and the second end of the elastic support member is configured to adjust an elastic force of the elastic support member during sliding relative to the second connection portion. 
     
     
         9 . The back support assembly according to  claim 8 , wherein a mounting slot is defined in the second connection portion, and the second end of the elastic support member extends into the mounting slot and is slidable in the mounting slot; wherein
 an adjustment screw is rotatably arranged in the mounting slot, wherein a first end of the adjustment screw is threaded to the second end of the elastic support member extending into the mounting slot, and a knob is arranged at a second end of the adjustment screw; and   an opening is defined in a wall of the mounting slot, wherein a portion of the knob extends out of the opening, and the portion of the knob extending out of the opening is configured to receive a force and rotate to drive the adjustment screw to rotate, such that the second end of the elastic support member is driven to slide in the mounting slot to adjust the elastic force of the elastic support member.   
     
     
         10 . The back support assembly according to  claim 9 , wherein a limiting post is arranged in the mounting slot, and a guiding hole is defined in the second end of the elastic support member, wherein the limiting post is slidably engaged with the guiding hole to guide and limit sliding of the second end of the elastic support member. 
     
     
         11 . The back support assembly according to  claim 1 , wherein the elastic support member is in a strip shape extending in a vertical direction. 
     
     
         12 . The back support assembly according to  claim 1 , wherein the elastic support member is in a keel shape with a plurality of notches in both sides. 
     
     
         13 . The back support assembly according to  claim 12 , wherein the notches are tapered in shape with a cross-section resembling an inverted T, and a spacer is filled inside each of the notches. 
     
     
         14 . The back support assembly according to  claim 6 , wherein a dimension D 1  along a vertical direction of a top petal in the elastic support sheet is greater than a dimension D 2  along the vertical direction of a bottom petal in the elastic support sheet. 
     
     
         15 . A chair, comprising a back support assembly, wherein the back support assembly comprises:
 a back support frame having a connection portion;   an elastic support member in a strip shape, wherein two ends of the elastic support member are connected to the connection portion, and a middle section of the elastic support member is bent towards a direction facing away from the connection portion;   a plurality of elastic support rods arranged at an angle to each other, wherein a first end of each of the plurality of elastic support rods is connected to a first side of the middle section of the elastic support member, the first side being a side, facing away from the connection portion, of the middle section, and each of the plurality of elastic support rods is bent from the first side towards a direction facing away from the elastic support member; and   an elastic support sheet, wherein a second end of each of the plurality of elastic support rods is connected to a back face of the elastic support sheet, and a front face of the elastic support sheet allows a human back to lean against.   
     
     
         16 . The chair according to  claim 15 , wherein the elastic support sheet comprises a skeleton portion and a flexible portion, wherein the flexible portion is arranged around an outer periphery of the skeleton portion, a stiffness of the skeleton portion is greater than a stiffness of the flexible portion, and a second end of the elastic support rod is connected to a back face of the skeleton portion. 
     
     
         17 . The chair according to  claim 16 , wherein the skeleton portion and the flexible portion are made of a same material, and are designed as an integral structure, and a thickness of the skeleton portion is greater than a thickness of the flexible portion, such that the stiffness of the skeleton portion is greater than the stiffness of the flexible portion. 
     
     
         18 . The chair according to  claim 16 , wherein ventilation holes are defined in the flexible portion. 
     
     
         19 . The chair according to  claim 15 , wherein a mesh fabric mounting frame surrounding an outer periphery of the elastic support sheet is arranged on the back support frame, wherein the mesh fabric mounting frame is configured to be connected to an edge of mesh fabric, and the front face of the elastic support sheet is configured to be abutted against the mesh fabric and allow, together with the mesh fabric, the human back to lean against. 
     
     
         20 . The chair according to  claim 19 , wherein the elastic support sheet is in a four-petal shape that is mirror-symmetrical relative to a vertical line of symmetry.