Foldable unit and stackable frame having same

Abstract

A foldable unit includes a first section, a second section and a connection section. The first and second sections are pivotally coupled with each other at their proximal sides. The connection section has a first side pivotally coupled with a peripheral bar of the first section and a section side for detachably coupling the connection section with a structure. The foldable units can be used to make frames at different widths when unfolded to meet different needs of users and stackable when folded to save spaces.

What is claimed is: 
     
         1 . A foldable unit comprising:
 a first section comprising a first peripheral bar;   a second section, wherein the first section and the second section are pivotally coupled with each other at proximal sides thereof, thereby allowing the first and second sections to fold and unfold with respect to each other; and   a connection section having a first side and a second side, wherein:
 the first side of the connection section is pivotally coupled with the first peripheral bar of the first section, thereby allowing the connection section to fold and unfold with respect to the first section; 
 the second side is configured to be detachably coupled with a structure when the connection section is unfolded with respect to the first section; and 
 the connection section is disposed substantially within an interior defined by the first section when the connection section is folded with respect to the first section. 
   
     
     
         2 . The foldable unit of  claim 1 , wherein the connection section comprises:
 one or more first connectors at the first side of the connection section to pivotally couple the connection section with the first peripheral bar of the first section; and   one or more second connectors at the second side of the connection section to detachably couple the connection section with the structure.   
     
     
         3 . The foldable unit of  claim 2 , wherein each of the one or more first connectors is disposed at an interior side of the first peripheral bar when the foldable unit is folded. 
     
     
         4 . The foldable unit of  claim 2 , wherein a respective first connector in the one or more first connectors comprises a first portion pivotally connected to the first peripheral bar at an interior side of the first peripheral bar and a second portion abutting a top surface of the first peripheral bar when the connection section is unfolded with respect to the first section. 
     
     
         5 . The foldable unit of  claim 4 , wherein the first portion of the respective first connector is pivotally connected to a pivoting piece that is fixedly disposed or integrally formed at an interior surface of the first peripheral bar. 
     
     
         6 . The foldable unit of  claim 4 , wherein the first and second portions of the respective first connector are substantially perpendicular to each other. 
     
     
         7 . The foldable unit of  claim 2 , wherein the one or more second connectors are configured to detachably couple the connection section with a peripheral bar of the structure. 
     
     
         8 . The foldable unit of  claim 7 , wherein a respective second connector in the one or more second connectors comprises a slot to receive at least a portion of the peripheral bar of the structure. 
     
     
         9 . The foldable unit of  claim 8 , wherein the slot comprises a portion abutting a top surface of the peripheral bar of the structure when the connection section is coupled with the structure. 
     
     
         10 . The foldable unit of  claim 7 , wherein a respective second connector in the one or more second connectors is secured on the peripheral bar of the structure by a fastener. 
     
     
         11 . The foldable unit of  claim 2 , wherein the connection section comprises one or more lateral connection bars, wherein each of the one or more first connectors is disposed at a first end and each of the one or more second connectors is disposed at a second end of a corresponding lateral connection bar. 
     
     
         12 . The foldable unit of  claim 11 , wherein the connection section comprises a pair of first connectors, a pair of second connectors, and a pair of lateral connection bars, and further comprises one or more longitudinal connection bars each disposed between and connected to the pair of lateral connection bars. 
     
     
         13 . The foldable unit of  claim 1 , further comprising:
 a first leg assembly pivotally coupled with the first section at a distal side of the first section;   a second leg assembly pivotally coupled with the second section at a distal side of the second section; and   a third leg assembly pivotally coupled with the proximal sides of the first and second sections.   
     
     
         14 . The foldable unit of  claim 1 , wherein the first and second sections are substantially the same. 
     
     
         15 . A foldable frame comprising:
 a first foldable unit and a second foldable unit disposed side by side, each of the first and second foldable units comprising:
 a first section comprising a first peripheral bar; 
 a second section comprising a second peripheral bar, wherein the first section and the second section are pivotally coupled with each other at proximal sides thereof, thereby allowing the first section and the second section to fold and unfold with respect to each other; and 
 a connection section having a first side and a second side, wherein the first side of the connection section is pivotally coupled with the first peripheral bar of the first section, thereby allowing the connection section to fold and unfold with respect to the first section; 
   wherein when the connection section of each of the first and second foldable units is unfolded, the second side of the connection section of the first foldable unit is detachably coupled with the second peripheral bar of the second section of the second foldable unit, and the second side of the connection section of the second foldable unit is detachably coupled with the second peripheral bar of the second section of the first foldable unit, thereby producing the foldable frame at a first width; and   wherein when the connection section of each of the first and second foldable units is folded, the first peripheral bar of the first section of the first foldable unit is detachably coupled with the second peripheral bar of the second section of the second foldable unit, and the second peripheral bar of the second section of the first foldable unit is detachably coupled with the first peripheral bar of the first section of the second foldable unit, thereby producing the foldable frame at a second width.   
     
     
         16 . The foldable structure of  claim 15 , wherein the connection section of the first foldable unit comprises:
 one or more first connectors at the first side of the connection section to pivotally couple the connection section with the first peripheral bar of the first section of the first foldable unit; and   one or more second connectors disposed at the second side of the connection section to detachably couple the connection section with the second peripheral bar of the second section of the second foldable unit.   
     
     
         17 . The foldable structure of  claim 15 , wherein the first and second foldable units are substantially the same. 
     
     
         18 . The foldable structure of  claim 15 , wherein for each of the first and second foldable units, the connection section is disposed substantially within an interior defined by the first section when the connection section is folded with respect to the first section. 
     
     
         19 . The foldable structure of  claim 15 , wherein the first and second foldable units are stackable when folded. 
     
     
         20 . A foldable frame comprising:
 a first foldable unit and a second foldable unit, each comprising:
 a first section comprising a first peripheral bar; 
 a second section comprising a second peripheral bar, wherein the first section and the second section are pivotally coupled with each other at proximal sides thereof, thereby allowing the first section and the second section to fold and unfold with respect to each other; and 
 a connection section having a first side and a second side, wherein the first side of the connection section is pivotally coupled with the first peripheral bar of the first section, thereby allowing the connection section to fold and unfold with respect to the first section; 
   wherein when the connection section of each of the first and second foldable units is unfolded, the second side of the connection section of the first foldable unit is detachably coupled with the second peripheral bar of the second section of the second foldable unit, and the second side of the connection section of the second foldable unit is detachably coupled with the second peripheral bar of the second section of the first foldable unit; and   wherein for each of the first and second foldable units, the connection section is disposed substantially within an interior defined by the first section when the connection section is folded with respect to the first section such that the first and second foldable units are stackable when folded.