Unlocking device for foldable chair and foldable chair with unlocking device

Abstract

A foldable chair with an unlocking device includes a chair seat, a foldable chair frame including a rear supporting pedestal, a left and a right front supporting pedestal, a left and a right side connecting rod, a left and a right front connecting rod, a rotary connecting piece whose right end is connected with right front connecting rod, a ratchet connected with a left end of rotary connecting piece, an unlocking handle, and an elastic piece. A part of a periphery of the ratchet has a tooth, and the ratchet is connected with a right end of left front connecting rod. The unlocking handle is connected with rotary connecting piece and provided with a pawl engaged with tooth. The elastic piece is connected with rotary connecting piece and abutted against unlocking handle. The unlocking device is adapted for the foldable chair.

What is claimed is: 
     
         1 . An unlocking device for a foldable chair, wherein a chair frame of the foldable chair comprises a front connecting rod, the front connecting rod comprises a left front connecting rod and a right front connecting rod, and the unlocking device comprising:
 a rotary connecting piece, wherein a right end of the rotary connecting piece is fixedly connected with a left end of the right front connecting rod, and a right end of the left front connecting rod abuts against or contacts with a left front side of the rotary connecting piece;   a ratchet which is rotationally connected with a left end of the rotary connecting piece, wherein only a part of a periphery of the ratchet is provided with a tooth, and the ratchet is fixedly connected with a right end of the left front connecting rod;   an elastic piece, wherein one end of the elastic piece is connected with the rotary connecting piece and abuts against the rotary connecting piece; and   an unlocking handle, wherein one end of the unlocking handle is rotatably connected with the rotary connecting piece, and is provided with a pawl engaged with the tooth on the ratchet thereon, wherein the other end of the elastic piece abuts against the other end of the unlocking handle, and drives the pawl to abut against the tooth on the ratchet and restricts the ratchet from rotating counterclockwise; and when the other end of the unlocking handle is pressed, the pawl is separated from the tooth on the ratchet, and the ratchet rotates counterclockwise.   
     
     
         2 . The unlocking device for the foldable chair according to  claim 1 , wherein an inside of the rotary connecting piece is hollow, and left, right and front sides of the rotary connecting piece are all open, and left ends of the ratchet and the unlocking handle are rotatably connected with a top of the rotary connecting piece and a bottom of the rotary connecting piece through a first axis and a second axis respectively; and when the pawl abuts against the tooth on the ratchet, the rotary connecting piece extends along a length direction of the front connecting rod, the ratchet, the pawl, the unlocking handle, the elastic piece, the right end of the left front connecting rod and the left end of the right front connecting rod are all located in the rotary connecting piece, the unlocking handle is located between the ratchet and the right front connecting rod, and the tooth on the ratchet is located at a rear right part of the ratchet. 
     
     
         3 . The unlocking device for the foldable chair according to  claim 1 , wherein the elastic piece is a spring. 
     
     
         4 . The unlocking device for the foldable chair according to  claim 2 , wherein the left front connecting rod and the right front connecting rod are coaxially arranged. 
     
     
         5 . The unlocking device for the foldable chair according to  claim 2 , wherein a front side of the rotary connecting piece is provided with one limiting rod, and when the pawl contacts with the limiting rod, the pawl is engaged with the tooth on the ratchet. 
     
     
         6 . A foldable chair with the unlocking device according to  claim 1 , comprising:
 a chair seat; and   a foldable chair frame, wherein the chair seat is arranged on the foldable chair frame, and the foldable chair frame comprises:   a rear supporting pedestal;   two front supporting pedestals which comprise a left front supporting pedestal and a right front supporting pedestal, wherein the left front supporting pedestal and the right front supporting pedestal are symmetrically arranged in front of the rear supporting pedestal;   two side connecting rods which comprise a left side connecting rod and a right side connecting rod, wherein two ends of the left side connecting rod are rotationally connected with the rear supporting pedestal and the left front supporting pedestal respectively, and two ends of the right side connecting rod are rotationally connected with the rear supporting pedestal and the right front supporting pedestal respectively;   a front connecting rod, which comprises a left front connecting rod and a right front connecting rod, wherein a left end of the left front connecting rod is rotationally connected with the left front supporting pedestal, and a right end of the right front connecting rod is rotationally connected with the right front supporting pedestal;   a rotary connecting piece, wherein a right end of the rotary connecting piece is fixedly connected with a left end of the right front connecting rod, and a right end of the left front connecting rod abuts against or contacts with a left front side of the rotary connecting piece;   a ratchet which is rotationally connected with a left end of the rotary connecting piece, wherein only a part of a periphery of the ratchet is provided with a tooth, and the ratchet is fixedly connected with a right end of the left front connecting rod;   an elastic piece, wherein one end of the elastic piece is connected with the rotary connecting piece and abuts against the rotary connecting piece; and   an unlocking handle, wherein one end of the unlocking handle is rotatably connected with the rotary connecting piece, and is provided with a pawl engaged with the tooth on the ratchet thereon, wherein the other end of the elastic piece abuts against the other end of the unlocking handle, and drives the pawl to abut against the tooth on the ratchet and restricts the ratchet from rotating counterclockwise; and when the other end of the unlocking handle is pressed, the pawl is separated from the tooth on the ratchet, and the ratchet rotates counterclockwise.   
     
     
         7 . The foldable chair with the unlocking device according to  claim 6 , wherein an inside of the rotary connecting piece is hollow, and left, right and front sides of the rotary connecting piece are all open, and left ends of the ratchet and the unlocking handle are rotatably connected with a top of the rotary connecting piece and a bottom of the rotary connecting piece through a first axis and a second axis respectively; and when the pawl abuts against the tooth on the ratchet, the rotary connecting piece extends along a length direction of the front connecting rod, the ratchet, the pawl, the unlocking handle, the elastic piece, the right end of the left front connecting rod and the left end of the right front connecting rod are all located in the rotary connecting piece, the unlocking handle is located between the ratchet and the right front connecting rod, and the tooth on the ratchet is located at a rear right part of the ratchet. 
     
     
         8 . The foldable chair with the unlocking device according to  claim 6 , wherein the elastic piece is a spring. 
     
     
         9 . The foldable chair with the unlocking device according to  claim 7 , wherein the left front connecting rod and the right front connecting rod are coaxially arranged. 
     
     
         10 . The foldable chair with the unlocking device according to  claim 7 , wherein a front side of the rotary connecting piece is provided with one limiting rod, and when the pawl contacts with the limiting rod, the pawl is engaged with the tooth on the ratchet.