Frame assembly capable of self-stretching fabrics evenly

Abstract

A frame assembly capable of self-stretching fabric evenly has an outer frame, a demountable inner frame mounted in the outer frame and a positioning mechanism with retaining flaps and engaging sections disposed between the inner frame and the outer frame. A patterned fabric covers a front of the inner frame and is wrapped on an outer annular surface of the inner frame. The inner frame is then pushed into the outer frame, so the fabric is held between the outer frame and the inner frame, and is stretched and evenly smoothed by the positioning mechanism of the frame assembly. When the inner frame is pushed out of outer frame, the fabric can be changed and replaced with another fabric with a different pattern. Therefore, replacing the fabrics on the frame assembly is easy and the fabrics are not damaged.

What is claimed is: 
     
         1 . A frame assembly comprising:
 an outer frame being annular and having an inner annular surface;   a demountable inner frame being annular, mounted in the outer frame and having an outer annular surface; and   a positioning mechanism having multiple resilient retaining flaps and multiple engaging sections, the retaining flaps and the engaging sections formed on the inner annular surface of the outer frame and the outer annular surface of the inner frame respectively, and each engaging section pressing against and engaging a corresponding retaining flap when the inner frame is mounted in the outer frame.   
     
     
         2 . The frame assembly as claimed in  claim 1 , wherein
 each retaining flap is arced in cross-section and has a rough gripping portion formed on an outer surface of the retaining flap; and   each engaging section of the inner frame is rough.   
     
     
         3 . The frame assembly as claimed in  claim 2 , wherein
 each gripping portion has multiple engagement teeth; and   each engaging section has multiple engagement teeth.   
     
     
         4 . The frame assembly as claimed in  claim 3 , wherein
 the inner annular surface of the outer frame has a rear annular edge and a front annular edge;   the retaining flaps are formed on the inner annular surface of the outer frame, and each retaining flap protrudes from the rear annular edge of the inner annular surface of the outer frame toward the front annular edge of the inner annular surface of the outer frame;   the engaging sections are formed on the outer annular surface of the inner frame.   
     
     
         5 . The frame assembly as claimed in  claim 1 , wherein
 the outer frame further has:
 multiple outer frame strips annularly arranged, each outer frame strip having an inner surface, and the inner surfaces of the outer frame strips forming the inner annular surface of the outer frame; and 
 multiple outer frame fastening brackets respectively connecting the outer frame strips, each outer frame fastening bracket connecting two of the outer frame strips that are arranged adjacent to each other; 
   the retaining flaps are respectively formed on the inner surfaces of the outer frame strips;   the inner frame further has:
 multiple inner frame strips annularly arranged, each inner frame strip having an outer surface forming an outer annular surface of the inner frame; and 
 multiple inner frame fastening brackets respectively connecting the inner frame strips, each inner frame fastening bracket connecting two of the inner frame strips that are arranged adjacent to each other; and 
   the engaging sections are respectively formed on the outer surfaces of the inner frame strips.   
     
     
         6 . The frame assembly as claimed in  claim 2 , wherein
 the outer frame further has:
 multiple outer frame strips annularly arranged, each outer frame strip having an inner surface, and the inner surfaces of the outer frame strips forming the inner annular surface of the outer frame; and 
 multiple outer frame fastening brackets respectively connecting the outer frame strips, each outer frame fastening bracket connecting two of the outer frame strips that are arranged adjacent to each other; 
   the retaining flaps are respectively formed on the inner surfaces of the outer frame strips;   the inner frame further has:
 multiple inner frame strips annularly arranged, each inner frame strip having an outer surface forming the outer annular surface of the inner frame; and 
 multiple inner frame fastening brackets respectively connecting the inner frame strips, each inner frame fastening bracket connecting two of the inner frame strips that are arranged adjacent to each other; and 
   the engaging sections are respectively formed on the outer surfaces of the inner frame strips.   
     
     
         7 . The frame assembly as claimed in  claim 3 , wherein
 the outer frame further has:
 multiple outer frame strips annularly arranged, each outer frame strip having an inner surface, and the inner surfaces of the outer frame strips forming the inner annular surface of the outer frame; and 
 multiple outer frame fastening brackets respectively connecting the outer frame strips, each outer frame fastening bracket connecting two of the outer frame strips that are arranged adjacent to each other; 
   the retaining flaps are respectively formed on the inner surfaces of the outer frame strips;   the inner frame further has:
 multiple inner frame strips annularly arranged, each inner frame strip having an outer surface forming the outer annular surface of the inner frame; and 
 multiple inner frame fastening brackets respectively connecting the inner frame strips, each inner frame fastening bracket connecting two of the inner frame strips that are arranged adjacent to each other; and 
   the engaging sections are respectively formed on the outer surfaces of the inner frame strips.   
     
     
         8 . The frame assembly as claimed in  claim 4 , wherein
 the outer frame further has:
 multiple outer frame strips annularly arranged, each outer frame strip having an inner surface, and the inner surfaces of the outer frame strips forming the inner annular surface of the outer frame; and 
 multiple outer frame fastening brackets respectively connecting the outer frame strips, each outer frame fastening bracket connecting two of the outer frame strips that are arranged adjacent to each other; 
   the retaining flaps are respectively formed on the inner surfaces of the outer frame strips;   the inner frame further has:
 multiple inner frame strips annularly arranged, each inner frame strip having an outer surface forming the outer annular surface of the inner frame; and 
 multiple inner frame fastening brackets respectively connecting the inner frame strips, each inner frame fastening bracket connecting two of the inner frame strips that are arranged adjacent to each other; and 
   the engaging sections are respectively formed on the outer surfaces of the inner frame strips.   
     
     
         9 . The frame assembly as claimed in  claim 5 , wherein each inner frame strip of the inner frame further has an inner surface and a mounting groove formed in the inner surface of the inner frame strip, extending axially along the inner frame strip and communicating with the mounting grooves of the other inner frame strips that are arranged adjacent to the inner frame strip. 
     
     
         10 . The frame assembly as claimed in  claim 8 , wherein each inner frame strip of the inner frame further has an inner surface and a mounting groove formed in the inner surface of the inner frame strip, extending axially along the inner frame strip and communicating with the mounting grooves of the other inner frame strips that are arranged adjacent to the inner frame strip. 
     
     
         11 . The frame assembly as claimed in  claim 9  further comprising a backing panel mounted between the inner frame strips of the inner frame and having an outer peripheral edge mounted in the mounting grooves of the inner frame strips of the inner frame. 
     
     
         12 . The frame assembly as claimed in  claim 10  further comprising a backing panel mounted between the inner frame strips of the inner frame and having an outer peripheral edge mounted in the mounting grooves of the inner frame strips of the inner frame. 
     
     
         13 . The frame assembly as claimed in  claim 11 , wherein
 the inner surface of each outer frame strip has a front edge; and   each outer frame strip of the outer frame further has a decorating panel formed on and protruding from the inner surface of the outer frame strip, and disposed along the front edge of the inner surface of the outer frame strip.   
     
     
         14 . The frame assembly as claimed in  claim 12 , wherein
 the inner surface of each outer frame strip has a front edge; and   each outer frame strip of the outer frame further has a decorating panel formed on and protruding from the inner surface of the outer frame strip, and disposed along the front edge of the inner surface of the outer frame strip.   
     
     
         15 . The frame assembly as claimed in  claim 14 , wherein
 each outer frame fastening bracket of the outer frame has:
 a connector mounted on rear surfaces of the outer frame strips; and 
 multiple fasteners separately mounted through the connector of the outer frame fastening bracket and securely attached to the outer frame strips; and 
   each inner frame fastening bracket of the outer frame has:
 a connector mounted on rear surfaces of the inner frame strips; and 
 multiple fasteners separately mounted through the connector of the inner frame fastening bracket and securely attached to the inner frame strips. 
   
     
     
         16 . The frame assembly as claimed in  claim 15 , wherein
 the connectors of the outer frame fastening brackets and the inner frame fastening brackets are corner braces;   the fasteners of the outer frame fastening brackets and the inner frame fastening brackets are screws.