Convertible sofa

Abstract

The present invention is for a method of converting a standard jack knife hinge into a new hinge, which allows access to a storage area underneath the seat bottom while retaining the ability to be used as a sofa and a bed. The new hinge is created by removing the seat bottom frame from the seat bottom bracket, fixably attaching a first attachment bracket to the seat bottom frame, pivotally attaching the first attachment bracket to a second attachment bracket, and fixably attaching the seat bottom bracket and the second attachment bracket to the seat base frame. The present invention also claims the finished combined hinge as well as a convertible sofa utilizing the new hinge.

What is claimed is:  
     
         1 . A method of making an improved convertible sofa hinge from a standard convertible sofa jack knife hinge, the jack knife hinge connecting a seat back frame and a seat bottom frame to a seat base frame including a side rail, the jack knife hinge having a seat back bracket fixably connected to the seat back frame, a seat bottom bracket fixably connected to the seat bottom frame, the seat back bracket pivotally connected to the seat bottom bracket, a first pivot arm pivotally connected to the side rail and the seat back bracket, a second pivot arm pivotally connected to the side rail and the seat bottom bracket, the cross bar arm pivotally attached to the first pivot arm and the second pivot arm, the method comprising the following steps: 
 a) removing the seat bottom frame from the seat bottom bracket;    b) fixably attaching a first attachment bracket to the seat bottom frame;    c) pivotally attaching the first attachment bracket to a second attachment bracket; and    d) fixably attaching the seat bottom bracket and the second attachment bracket to the seat base frame.    
     
     
         2 . The method of  claim 1  further comprising the following steps: 
 e) removing the seat back frame from the seat back bracket;  
 f) fixably attaching a third attachment bracket to the seat back frame;  
 g) pivotally attaching the third attachment bracket to a fourth attachment bracket; and  
 h) fixably attaching the fourth attachment bracket to the seat back bracket.  
 
     
     
         3 . The method of  claim 1  further comprising the following steps: 
 e) attaching a locking pin to the first attachment bracket;  
 f) providing an aperture in the second attachment bracket such that the locking pin engages the aperture when the seat bottom frame is in a seat configuration.  
 
     
     
         4 . The method of  claim 1  further comprising the following steps: 
 e) attaching a locking pin to the first attachment bracket;  
 f) providing an aperture in the second attachment bracket such that the locking pin engages the aperture when the seat bottom frame is raised to a storage access configuration.  
 
     
     
         5 . A method of making an improved convertible sofa hinge from a standard convertible sofa jack knife hinge, the jack knife hinge connecting a seat back frame and a seat bottom frame to a seat base frame including a side rail, the jack knife hinge having a seat back bracket fixably connected to the seat back frame, a seat bottom bracket fixably connected to the seat bottom frame, the seat back bracket pivotally connected to the seat bottom bracket, a first pivot arm pivotally connected to the side rail and the seat back bracket, a second pivot arm pivotally connected to the side rail and the seat bottom bracket, the cross bar arm pivotally attached to the first pivot arm and the second pivot arm, the method comprising the following steps: 
 a) removing the seat back frame from the seat back bracket;    b) fixably attaching a first attachment bracket to the seat back frame;    c) pivotally attaching the first attachment bracket to a second attachment bracket; and    d) fixably attaching the second attachment bracket to the seat back bracket.    
     
     
         6 . The method of  claim 1  further comprising the following steps: 
 e) attaching a locking pin to the first attachment bracket;  
 f) providing an aperture in the second attachment bracket such that the locking pin engages the aperture when the seat back frame is in a seat configuration.  
 
     
     
         7 . The method of  claim 1  further comprising the following steps: 
 e) attaching a locking pin to the first attachment bracket;  
 f) providing an aperture in the second attachment bracket such that the locking pin engages the aperture when the seat back frame is lowered to an access configuration.  
 
     
     
         8 . A hinge assembly for a convertible sofa, the hinge connecting a seat back frame and a seat bottom frame to a seat base frame including a side rail, the hinge for a convertible sofa comprising: 
 a seat back bracket fixably connected to the seat back frame,    a seat bottom bracket pivotally connected to the seat back bracket,    a first pivot arm pivotally connected to the side rail and the seat back bracket,    a second pivot arm pivotally connected to the side rail and the seat bottom bracket,    a cross bar arm pivotally attached to the first pivot arm and the second pivot arm,    a first attachment bracket fixably attached to the seat bottom frame,    a second attachment bracket pivotally attached the first attachment bracket, and    wherein the seat bottom bracket and the second attachment bracket are fixably attached to the seat base frame.    
     
     
         9 . The hinge assembly of  claim 8  further comprising: 
 a third attachment bracket fixably attached to the seat back frame,  
 a fourth attachment bracket pivotally attached the third attachment bracket, and  
 wherein the fourth attachment bracket is fixably attached to the seat back bracket.  
 
     
     
         10 . The hinge assembly of  claim 8  further comprising: 
 a locking pin attached to the first attachment bracket;  
 an aperture formed in the second attachment bracket;  
 wherein the locking pin engages the aperture in the second attachment bracket when the seat bottom frame is in a seat configuration, preventing movement of the seat bottom frame.  
 
     
     
         11 . The hinge assembly of  claim 8  further comprising: 
 a locking pin attached to the first attachment bracket;  
 an aperture formed in the second attachment bracket;  
 wherein the locking pin engages the aperture in the second attachment bracket when the seat bottom frame is raised to a storage access configuration.  
 
     
     
         12 . The hinge assembly of  claim 8  further comprising: 
 a slot formed in the first attachment bracket;  
 a pin projecting from the second attachment bracket through the slot formed in the first attachment bracket;  
 wherein the slot controls the movement of the first attachment bracket with respect to the second attachment bracket.  
 
     
     
         13 . The hinge assembly of  claim 12 , wherein the slot has at least one portion formed as an arc.  
     
     
         14 . The hinge assembly of  claim 12 , wherein the slot has at least one portion formed as a straight section.  
     
     
         15 . A hinge assembly for a convertible sofa, the hinge connecting a seat back frame and a seat bottom frame to a seat base frame including a side rail, the hinge for a convertible sofa comprising: 
 a seat back bracket fixably connected to the seat back frame,    a seat bottom bracket pivotally connected to the seat back bracket,    a first pivot arm pivotally connected to the side rail and the seat back bracket,    a second pivot arm pivotally connected to the side rail and the seat bottom bracket,    a cross bar arm pivotally attached to the first pivot arm and the second pivot arm,    a first attachment bracket fixably attached to the seat back frame,    a second attachment bracket pivotally attached the first attachment bracket, and    wherein the second attachment bracket is fixably attached to the seat back bracket.    
     
     
         16 . The hinge assembly of  claim 15  further comprising: 
 a locking pin attached to the first attachment bracket;  
 an aperture formed in the second attachment bracket;  
 wherein the locking pin engages the aperture in the second attachment bracket when the seat back frame is in a seat configuration, preventing movement of the seat back frame.  
 
     
     
         17 . The hinge assembly of  claim 15  further comprising: 
 a locking pin attached to the first attachment bracket;  
 an aperture formed in the second attachment bracket;  
 wherein the locking pin engages the aperture in the second attachment bracket when the seat back frame is rotated downward from a seat configuration.  
 
     
     
         18 . The hinge assembly of  claim 8  further comprising: 
 a slot formed in the first attachment bracket;  
 a pin projecting from the second attachment bracket through the slot formed in the first attachment bracket;  
 wherein the slot controls the movement of the first attachment bracket with respect to the second attachment bracket.  
 
     
     
         19 . The hinge assembly of  claim 12 , wherein the slot has at least one portion formed as an arc.  
     
     
         20 . A convertible sofa comprising: 
 a seat back frame;    a seat bottom frame;    a seat base frame including a side rail on opposite sides of the seat base frame wherein the seat base frame encloses a storage area;    a pair of hinges connecting the seat back frame and the seat bottom frame to the seat base frame, wherein each hinge comprises a seat back bracket fixably connected to the seat back frame, a seat bottom bracket pivotally connected to the seat back bracket, a first pivot arm pivotally connected to the side rail and the seat back bracket, a second pivot arm pivotally connected to the side rail and the seat bottom bracket, a cross bar arm pivotally attached to the first pivot arm and the second pivot arm, a first attachment bracket fixably attached to the seat bottom frame, a second attachment bracket pivotally attached the first attachment bracket;    wherein the seat bottom bracket and the second attachment bracket are fixably attached to the seat base.    
     
     
         21 . The convertible sofa of  claim 20  further comprising: 
 a third attachment bracket fixably attached to the seat back frame,  
 a fourth attachment bracket pivotally attached the third attachment bracket, and  
 wherein the fourth attachment bracket is fixably attached to the seat back bracket.  
 
     
     
         22 . The convertible sofa of  claim 20  further comprising: 
 a locking pin attached to the first attachment bracket;  
 an aperture formed in the second attachment bracket;  
 wherein the locking pin engages the aperture in the second attachment bracket when the seat bottom frame is in a seat configuration, preventing movement of the seat bottom frame.  
 
     
     
         23 . The convertible sofa of  claim 20  further comprising: 
 a locking pin attached to the first attachment bracket;  
 an aperture formed in the second attachment bracket;  
 wherein the locking pin engages the aperture in the second attachment bracket when the seat bottom frame is raised to a storage access configuration.  
 
     
     
         24 . The convertible sofa of  claim 20  further comprising: 
 a slot formed in the first attachment bracket;  
 a pin projecting from the second attachment bracket through the slot formed in the first attachment bracket;  
 wherein the slot controls the movement of the first attachment bracket with respect to the second attachment bracket.  
 
     
     
         25 . The convertible sofa of  claim 24 , wherein the slot has at least one portion formed as an arc.  
     
     
         26 . A convertible sofa comprising: 
 a seat back frame;    a seat bottom frame;    a seat base frame including a side rail on opposite sides of the seat base frame wherein the seat base frame encloses a storage area;    a pair of hinges connecting the seat back frame and the seat bottom frame to the seat base frame, wherein each hinge comprises a seat back bracket fixably connected to the seat back frame, a seat bottom bracket pivotally connected to the seat back bracket, a first pivot arm pivotally connected to the side rail and the seat back bracket, a second pivot arm pivotally connected to the side rail and the seat bottom bracket, a cross bar arm pivotally attached to the first pivot arm and the second pivot arm, a first attachment bracket fixably attached to the seat back frame, a second attachment bracket pivotally attached the first attachment bracket, and    wherein the second attachment bracket is fixably attached to the seat back bracket.