Spring assisted sofa convertible into bunk bed

Abstract

A sofa bed is convertible to a bunk bed using a base frame assembly; an upper bunk assembly to be disposed on the base frame assembly in a seating position and to be disposed above the base frame assembly in a bunk bed position; a front link and a rear link pivotally attached to the base frame assembly and the upper bunk assembly, alternative embodiments adding a flange plate secured to the rear link with a motor, cable, drive, screw and drive assembly, or adding a torsion spring assembly, or substituting vertical scissors mechanism for the links or substituting telescoping supports for the link assemblies.

In accordance with the invention it is claimed: 
     
         1 . A sofa convertible into a bunk comprising:
 a base frame assembly;   a upper bunk assembly configured to be disposed on said base frame assembly in a seating position and to be disposed above said base frame assembly in a bunk bed position;   a rear link pivotally attached to said base frame assembly and said upper bunk assembly;   a torsion spring mounted to said rear link and said base frame assembly to distribute the gravitational force of said upper bunk assembly to said base frame assembly;   wherein a first end of said rear link is pivotally attached to said upper bunk assembly and a second end of said rear link is pivotally attached to said base frame assembly;   a rear timing arm is secured to said rear link;   a first end of said rear timing arm is secured to said second end of said rear link at a substantially right angle and said first end of said rear timing arm is pivotally attached to a timing link;   a front link is pivotally attached to said base frame assembly and said upper bunk assembly;   a first end of said front link is pivotally attached to said upper bunk assembly and a second end of said front link is pivotally attached to said base frame assembly;   a front timing arm is secured to said front link;   a first end of said front timing arm is secured proximate said second end of said front link at a substantially right angle and said first end of said front timing arm is pivotally attached to said timing link;   said timing link is pivotally attached to said front timing arm and pivotally attached to said rear timing arm;   a first end of said timing link is pivotally attached to a second end of said front timing arm and a second end of said timing link is pivotally attached to a second end of said rear timing arm;   said timing link maintains said front timing arm and said rear timing arm in parallel so that said front link and said rear link to move in parallel;   said torsion spring is mounted to said second end of said rear link and said torsion spring is twisted and has the most energy stored in said seating position;   said front link, rear link and timing link forming a first link assembly on a first side;   a second link assembly comprising a mirror image of said first link assembly is formed and arranged on a second said of said sofa   a timing tube interconnecting said first link assembly and said second link assembly.   
     
     
         2 . A sofa convertible into a bunk comprising:
 a base frame assembly;   a upper bunk assembly configured to be disposed on said base frame assembly in a seating position and to be disposed above said base frame assembly in a bunk bed position;   a rear link pivotally attached to said base frame assembly and said upper bunk assembly; and   a torsion spring mounted to said rear link and said base frame assembly to distribute the gravitational force of said upper bunk assembly to said base frame assembly.   
     
     
         3 . The sofa according to  claim 2 , wherein a first end of said rear link is pivotally attached to said upper bunk assembly and a second end of said rear link is pivotally attached to said base frame assembly. 
     
     
         4 . The sofa according to  claim 3  further comprising a rear timing arm secured to said rear link. 
     
     
         5 . The sofa according to  claim 4 , wherein a first end of said rear timing arm is secured proximate said second end of said rear link at a substantially right angle and said first end of said rear timing arm is pivotally attached to a timing link. 
     
     
         6 . The sofa according to  claim 5  further comprising a front link pivotally attached to said base frame assembly and said upper bunk assembly. 
     
     
         7 . The sofa according to  claim 6 , wherein a first end of said front link is pivotally attached to said upper bunk assembly and a second end of said front link is pivotally attached to said timing link. 
     
     
         8 . The sofa according to  claim 7  further comprising a front timing arm secured to said front link and pivotally attached to said timing link. 
     
     
         9 . The sofa according to  claim 8 , wherein a first end of said front timing arm is secured proximate said second end of said front link at a substantially right angle and said first end of said front timing arm is pivotally attached to said timing link. 
     
     
         10 . The sofa according to  claim 9  further comprising said a timing link pivotally attached to said front timing arm and pivotally attached to said rear timing arm. 
     
     
         11 . The sofa according to  claim 10 , wherein a first end of said timing link is pivotally attached to a second end of said front timing arm and a second end of said timing link is pivotally attached to a second end of said rear timing arm. 
     
     
         12 . The sofa according to  claim 11 , wherein said timing link maintains said front timing arm and said rear timing arm in parallel so that said front link and said rear link to move in parallel. 
     
     
         13 . A sofa convertible into a bunk comprising:
 a base frame assembly;   a upper bunk assembly configured to be disposed on said base frame assembly in a seating position and to be disposed above said base frame assembly in a bunk bed position;   a rear link pivotally attached to said base frame assembly and said upper bunk assembly;   a torsion spring mounted to said rear link and said base frame assembly having a first end mounted to said base frame assembly and a second end mounted to said rear link, wherein said torsion spring is twisted and has the most energy stored in said seating position.   
     
     
         14 . The sofa according to  claim 13 , further comprising:
 a first end of said rear link is pivotally attached to said upper bunk assembly;   a second end of said rear link is pivotally attached to said base frame assembly;   a rear timing arm is secured proximate said second end of said rear link at a substantially right angle and said first end of said rear timing arm is pivotally attached to a timing link.   
     
     
         15 . The sofa according to  claim 14 , further comprising:
 a front link pivotally attached to said base frame assembly and said upper bunk assembly;   a first end of said front link is pivotally attached to said upper bunk assembly and a second end of said front link is pivotally attached to said base frame assembly;   a front timing arm secured to said front link and pivotally attached to said timing link;   a first end of said front timing arm is secured proximate said second end of said front link at a substantially right angle and said first end of said front timing arm is pivotally attached to said timing link.   
     
     
         16 . The sofa according to  claim 15 , wherein said timing link maintains said front timing arm and said rear timing arm in parallel so that said front link and said rear link to move in parallel. 
     
     
         17 . The sofa according to  claim 16 , further comprising:
 said front link, rear link and timing link forming a first link assembly on a first side;   a second link assembly comprising a mirror image of said first link assembly is formed and arranged on a second said of said sofa.   
     
     
         18 . The sofa according to  claim 16 , wherein an elongated timing interconnector is fixed to said first link assembly and said second link assembly.