Extended leg mechanism, functional iron frame and movable sofa

Abstract

An extended leg mechanism includes a first leg connecting rod and a second leg connecting rod, where the first leg connecting rod, a third leg connecting rod, the second leg connecting rod and a fourth leg connecting rod are pivotally connected in sequence; the third and fourth leg connecting rods are pivotally connected to an identical first footrest assembly; the first footrest assembly includes a vertical plate pivotally connected to the third and fourth leg connecting rods, and a top portion of the vertical plate is provided with a mounting plate, where the vertical plate is pivotally connected to first and second footrest connecting rods, the other end of the first and second footrest connecting rods is pivotally connected to an identical second footrest assembly, and the second footrest assembly, a third footrest connecting rod and the fourth leg connecting rod are pivotally connected in sequence.

What is claimed is: 
     
         1 . An extended leg mechanism, comprising a first leg connecting rod and a second leg connecting rod, wherein a front end of the first leg connecting rod is pivotally connected to a third leg connecting rod, a rear portion of the third leg connecting rod is pivotally connected to a front portion of the second leg connecting rod, and a front end of the second leg connecting rod is pivotally connected to a fourth leg connecting rod; the third leg connecting rod and the fourth leg connecting rod are pivotally connected to an identical first footrest assembly; and the first footrest assembly comprises a vertical plate pivotally connected to the third leg connecting rod and the fourth leg connecting rod, and a top portion of the vertical plate is provided with a mounting plate, wherein the vertical plate is pivotally connected to first ends of a first footrest connecting rod and a second footrest connecting rod, second ends of the first footrest connecting rod and the second footrest connecting rod is pivotally connected to an identical second footrest assembly, a rear portion of the second footrest assembly is pivotally connected to a third footrest connecting rod, and a rear end of the third footrest connecting rod is pivotally connected to a front end of the fourth leg connecting rod. 
     
     
         2 . The extended leg mechanism according to  claim 1 , wherein a distance H 1  from an axis of a shaft where the fourth leg connecting rod is pivotally connected to the vertical plate to a top surface of the mounting plate is 120-140 mm. 
     
     
         3 . The extended leg mechanism according to  claim 2 , wherein a top portion of an inner side wall of the vertical plate is fixedly connected to a fourth footrest connecting rod, and a front end of the fourth footrest connecting rod extends out of the vertical plate and is pivotally connected to a rear end of the first footrest connecting rod. 
     
     
         4 . The extended leg mechanism according to  claim 1 , wherein a middle portion of the first leg connecting rod is provided with a first limiting pin, the second leg connecting rod is provided with a first limiting surface, wherein the first limiting surface cooperates with the first limiting pin, and the third leg connecting rod is provided with a second limiting surface, wherein the second limiting surface cooperates with the first limiting pin. 
     
     
         5 . The extended leg mechanism according to  claim 4 , wherein a front portion of the third leg connecting rod is provided with a second limiting pin, and the vertical plate is provided with a third limiting surface, wherein the third limiting surface cooperates with the second limiting pin. 
     
     
         6 . A functional iron frame, comprising two symmetrical seat frame mounting plates, wherein a front side of the seat frame mounting plate is provided with the extended leg mechanism according to  claim 1 , and a front end of the seat frame mounting plate is provided with an extension mounting plate. 
     
     
         7 . The functional iron frame according to  claim 6 , wherein a distance H 2  between a front end face of the extension mounting plate and a front end face of the seat frame mounting plate is 50-90 mm. 
     
     
         8 . A movable sofa, comprising a sofa seat, wherein the functional iron frame according to  claim 6  is provided in the sofa seat; and when the functional iron frame is in a sitting state, a distance H 3  from a highest point of the extension mounting plate to ground is 280-350 mm. 
     
     
         9 . The movable sofa according to  claim 8 , wherein a height of a sofa foot at a bottom portion of the sofa seat is 50-100 mm. 
     
     
         10 . The functional iron frame according to  claim 6 , wherein in the extended leg mechanism, a distance H 1  from an axis of a shaft where the fourth leg connecting rod is pivotally connected to the vertical plate to a top surface of the mounting plate is 120-140 mm. 
     
     
         11 . The functional iron frame according to  claim 10 , wherein in the extended leg mechanism, a top portion of an inner side wall of the vertical plate is fixedly connected to a fourth footrest connecting rod, and a front end of the fourth footrest connecting rod extends out of the vertical plate and is pivotally connected to a rear end of the first footrest connecting rod. 
     
     
         12 . The functional iron frame according to  claim 6 , wherein in the extended leg mechanism, a middle portion of the first leg connecting rod is provided with a first limiting pin, the second leg connecting rod is provided with a first limiting surface, wherein the first limiting surface cooperates with the first limiting pin, and the third leg connecting rod is provided with a second limiting surface, wherein the second limiting surface cooperates with the first limiting pin. 
     
     
         13 . The functional iron frame according to  claim 12 , wherein in the extended leg mechanism, a front portion of the third leg connecting rod is provided with a second limiting pin, and the vertical plate is provided with a third limiting surface, wherein the third limiting surface cooperates with the second limiting pin. 
     
     
         14 . The movable sofa according to  claim 8 , wherein in the functional iron frame, a distance H 2  between a front end face of the extension mounting plate and a front end face of the seat frame mounting plate is 50-90 mm. 
     
     
         15 . The functional iron frame according to  claim 10 , wherein a distance H 2  between a front end face of the extension mounting plate and a front end face of the seat frame mounting plate is 50-90 mm. 
     
     
         16 . The functional iron frame according to  claim 11 , wherein a distance H 2  between a front end face of the extension mounting plate and a front end face of the seat frame mounting plate is 50-90 mm. 
     
     
         17 . The functional iron frame according to  claim 12 , wherein a distance H 2  between a front end face of the extension mounting plate and a front end face of the seat frame mounting plate is 50-90 mm. 
     
     
         18 . The functional iron frame according to  claim 13 , wherein a distance H 2  between a front end face of the extension mounting plate and a front end face of the seat frame mounting plate is 50-90 mm. 
     
     
         19 . The movable sofa according to  claim 8 , wherein in the extended leg mechanism of the functional iron frame, a distance H 1  from an axis of a shaft where the fourth leg connecting rod is pivotally connected to the vertical plate to a top surface of the mounting plate is 120-140 mm. 
     
     
         20 . The movable sofa according to  claim 8 , wherein in the extended leg mechanism of the functional iron frame, a top portion of an inner side wall of the vertical plate is fixedly connected to a fourth footrest connecting rod, and a front end of the fourth footrest connecting rod extends out of the vertical plate and is pivotally connected to a rear end of the first footrest connecting rod.