Folding mechanism of sofa bed and sofa bed

Abstract

A folding mechanism of a sofa bed includes a left armrest, a right armrest, a bed frame, and a locking mechanism. The bed frame includes a first bed frame and a second bed frame. The first bed frame is fixedly connected to the left armrest and the right armrest. The second bed frame is rotatably connected to the left armrest and the right armrest. The left armrest and the right armrest are rotatably connected to the second bed frame through folding hinges. The folding hinge includes a first supporting arm and a second supporting arm which are pivotally connected to each other. The first supporting arm is fixedly connected to the left armrest or the right armrest, and the second supporting arm is fixedly connected to the second bed frame. The locking mechanism locks the first bed frame and the second bed frame in one or more relative positions.

What is claimed is: 
     
         1 . A folding mechanism of a sofa bed, comprising:
 a left armrest,   a right armrest,   a bed frame, and   a locking mechanism, wherein:
 the bed frame comprises a first bed frame and a second bed frame arranged in sequence along a width direction of the left armrest and the right armrest, 
 the first bed frame is fixedly connected to and located between the left armrest and the right armrest, 
 the second bed frame is rotatably connected to and located between the left armrest and the right armrest, 
 each of the left armrest and the right armrest is disposed with a folding hinge to enable the left armrest and the right armrest to be rotatably connected to the second bed frame, 
 the folding hinge comprises a first supporting arm and a second supporting arm, 
 a first end of the first supporting arm and a first end of the second supporting arm is pivotally connected to each other, 
 a second end of the first supporting arm is fixedly connected to a corresponding one of the left armrest or the right armrest, 
 a second end of the second supporting arm is fixedly connected to the second bed frame, and 
 the locking mechanism is configured to lock the first bed frame and the second bed frame in one or more relative positions. 
   
     
     
         2 . The folding mechanism of the sofa bed according to  claim 1 , wherein:
 the locking mechanism comprises a ratchet disposed on one of the first supporting arm or the second supporting arm and a pawl disposed on the other one of the first supporting arm or the second supporting arm,   the ratchet has at least two ratchet teeth arranged circumferentially, and   the pawl is configured to engage one of the at least two ratchet teeth to lock the second bed frame at different positions.   
     
     
         3 . The folding mechanism of the sofa bed according to  claim 1 , wherein:
 the second bed frame is configured to be in a first position and a second position relative to the first bed frame,   when the second bed frame is in the first position, an angle between the first bed frame and the second bed frame is 180°, and   when the second bed frame is in the second position, the angle between the first bed frame and the second bed frame is less than 180°.   
     
     
         4 . The folding mechanism of the sofa bed according to  claim 3 , wherein:
 the left armrest and the right armrest are fixedly connected by a lateral rod.   
     
     
         5 . The folding mechanism of the sofa bed according to  claim 4 , wherein:
 the lateral rod comprises one or more position-provided recesses, and   when the second bed frame is in the first position, one or more parts of the second bed frame that abut the lateral rod are disposed in the one or more position-provided recesses.   
     
     
         6 . A sofa bed, comprising:
 a bed board,   a cushion layer,   an elastic layer, and   the folding mechanism according to  claim 1 , wherein:
 the bed board is respectively connected to the first bed frame and the second bed frame. 
   
     
     
         7 . The sofa bed according to  claim 6 , wherein:
 the first bed frame comprises a plurality of first insertion holes located on two first side frames of the first bed frame along a length direction of the sofa bed,   the second bed frame comprises a plurality of second insertion holes located on two second side frames of the second bed frame along the length direction of the sofa bed, and   the plurality of first insertion holes and the plurality of second insertion holes are configured to fix the bed board.   
     
     
         8 . The sofa bed according to  claim 7 , wherein:
 a first one of the two first side frames of the first bed frame and a first one of the two second side frames of the second bed frame facing away from each other respectively comprises a first inner surface and a second inner surface on which a first set of the plurality of first insertion holes and a first set of the plurality of second insertion holes are respectively located at intervals, and   a second one of the two first side frames of the first bed frame and a second one of the two second side frames of the second bed frame facing each other respectively comprises a first upper surface and a second upper surface on which a second set of plurality of first insertion holes and a second set of the plurality of second insertion holes are respectively located at intervals.   
     
     
         9 . The sofa bed according to  claim 8 , wherein:
 the bed board comprises a plurality of grid-shaped bed board units,   a first side of each of the plurality of grid-shaped bed board units comprises a plurality of first insertion pins extending along a horizontal direction, and   a second side of each of the plurality of grid-shaped bed board units comprises a plurality of second insertion pins extending along a height direction.   
     
     
         10 . The sofa bed according to  claim 6 , wherein:
 the bed board is divided into a first bed board connected to the first bed frame and a second bed board connected to the second bed frame.   
     
     
         11 . The sofa bed according to  claim 10 , wherein:
 each of the left armrest and the right armrest extends in a direction in which the left armrest and the right armrest face each other to form a supporting rod for supporting the first bed frame,   the supporting rod comprises a first connecting groove, and   the first bed frame comprises one or more first connecting columns configured to be matched with the first connecting groove.   
     
     
         12 . The sofa bed according to  claim 11 , wherein:
 the first connecting groove is divided into a first portion and a second portion which are in communication with each other,   a distal end of each of the one or more first connecting columns radially extends outward to form a flange,   a diameter of the first portion is larger than a diameter of the flange, and   a diameter of the second portion is smaller than the diameter of the flange.   
     
     
         13 . The sofa bed according to  claim 10 , wherein:
 the first bed frame and the second bed frame are connected to the first bed board and the second bed board by screws respectively.   
     
     
         14 . The sofa bed according to  claim 13 , wherein:
 an end of the second supporting arm away from the first supporting arm extends to form a supporting surface for supporting the second bed board,   the supporting surface comprises a second connecting groove, and   the second bed frame comprises one or more second connecting columns configured to be matched with the second connecting groove.   
     
     
         15 . The sofa bed according to  claim 14 , wherein:
 the second connecting groove is divided into a first portion and a second portion which are in communication with each other,   a distal end of each of the one or more second connecting columns radially extends outward to form a flange,   a diameter of the first portion is larger than a diameter of the flange, and   a diameter of the second portion is smaller than the diameter of the flange.   
     
     
         16 . The sofa bed according to  claim 10 , wherein:
 the bed board comprises a third bed board connected to the first bed board,   the third bed board is connected to a side of the first bed board adjacent to the second bed board,   the third bed board is arranged at an obtuse angle relative to the first bed board, and   a distal end of the third bed board is connected to a first group of a plurality of elastic units on the first bed board adjacent to the second bed board.   
     
     
         17 . The sofa bed according to  claim 10 , wherein:
 the bed board comprises at least one set of two sub-bed boards, and   the two sub-bed boards are pivotally connected to each other, so that the bed board has an unfolded state and a folded state.   
     
     
         18 . The sofa bed according to  claim 17 , wherein:
 one or more middle legs are provided for supporting the two sub-bed boards,   opposite sides of the two sub-bed boards are each disposed with one or more connecting lugs,   when the bed board is in the unfolded state, two sets of the one or more connecting lugs that respectively belong to the two sub-bed boards are misaligned with each other in a height direction so that connecting holes respectively on the two sets of the one or more connecting lugs are aligned with each other, and   the one or more middle legs have pins passing through the connecting holes to fix the first bed board in the unfolded state.   
     
     
         19 . The sofa bed according to  claim 6 , wherein:
 a surface of the bed board is disposed with a plurality of connecting assemblies configured to be connected to the elastic layer and spaced apart from each other, and   a side of the elastic layer facing the bed board comprise one or more connecting matching assemblies configured to be matched with the plurality of connecting assemblies.   
     
     
         20 . The sofa bed according to  claim 19 , wherein:
 the plurality of connecting assemblies are I-shaped protrusions extending in a height direction.   
     
     
         21 . The sofa bed according to  claim 19 , wherein:
 each of the plurality of connecting assemblies comprises a fixed tapered upper cover and a fixed tapered lower cover,   the fixed tapered upper cover and the fixed tapered lower cover are respectively disposed on an upper side and a lower side of the bed board in a thickness direction of the bed board,   the fixed tapered lower cover passes through the bed board and is fixedly connected to the fixed tapered upper cover,   the fixed tapered upper cover is tapered, and   the one or more connecting matching assemblies are one or more tapered holes.   
     
     
         22 . The sofa bed according to  claim 6 , wherein:
 the elastic layer comprises a plurality of first connecting members spaced apart from each other in a circumferential direction of the elastic layer,   a lower surface of the cushion layer comprises a plurality of second connecting members spaced apart from each other in a circumferential direction of the cushion layer, and   the plurality of first connecting members are connected to the plurality of second connecting members through one or more intermediate connecting members.   
     
     
         23 . The sofa bed according to  claim 22 , wherein:
 the plurality of first connecting members and the plurality of second connecting members are insertion slots, and   the one or more intermediate connecting members are respectively connected to the plurality of first connecting members and the plurality of second connecting members.   
     
     
         24 . The sofa bed according to  claim 23 , wherein:
 each of the one or more intermediate connecting members comprises a connecting belt and two insertion blocks disposed at two ends of the connecting belt.   
     
     
         25 . The sofa bed according to  claim 22 , wherein:
 the elastic layer comprises a plurality of elastic units arranged in an array arrangement, and   adjacent elastic units of the plurality of elastic units are connected together to form the elastic layer.   
     
     
         26 . The sofa bed according to  claim 25 , wherein:
 each of the plurality of elastic units is disposed with a correspond set of the plurality of first connecting members respectively located on two first sides of a corresponding one of the plurality of elastic units in a transverse direction of the array arrangement and two second sides of the corresponding one of the plurality of elastic units in a longitudinal direction of the array arrangement, and   adjacent two first connecting members of the plurality of first connecting members that respectively belong to adjacent two elastic units of the plurality of elastic units are connected by a corresponding one of the one or more intermediate connecting members.   
     
     
         27 . The sofa bed according to  claim 6 , wherein:
 the cushion layer is fixedly connected to the bed frame.