Patent Publication Number: US-6708630-B2

Title: Foldable side support arrangement for foldable furniture

Description:
BACKGROUND OF THE PRESENT INVENTION 
     1. Field of Invention 
     The present invention relates to a foldable furniture, and more particularly to a foldable side support arrangement for a foldable furniture which is more comfortable and capable of supporting more weight comparing with the conventional foldable furniture. 
     2. Description of Related Arts 
     A conventional foldable furniture, such as a foldable bed, a foldable table, or a foldable chair, generally comprises a foldable frame constructed by metal tubes and a supporting fabric. The foldable frame comprises a plurality pairs of construction tubes for supporting the supporting fabric in a tense manner wherein each pair of construction tubes are pivotally connected together where they cross so that the foldable frame can be easily unfolded to provide a rigid cross-support for use and be folded for storage. Since the conventional foldable furniture can be quickly and easily unfolded for use and folded into a compact unit for carriage, the user can carry the foldable furniture to everywhere such as campground or beach. 
     However, the conventional foldable furniture has a major drawback. Since the supporting fabric is suspendedly supported by the foldable frame, the supporting fabric may not be substantially supported in a tense manner when the foldable furniture is in the unfolded condition. When a downward pulling force is applied on the supporting fabric, the supporting fabric will be stretched to the center thereof. Especially for the foldable bed, most of the users have an intention to plunge into the foldable bed downwardly when the downward pulling force of the weight of the user is exerted on the supporting fabric. 
     Furthermore, stresses are created by the downward pulling force at the connecting joints where the construction tubes are connected with each other. The user&#39;s weight causes the supporting fabric to be pulled away from the connecting joints such that stress will be created at the connecting joints. The stress will then cause a tear along the area of the supporting fabric at the connecting joint so that the supporting fabric will be permanently misshapen at the stress point over a period of continuous use. 
     SUMMARY OF THE PRESENT INVENTION 
     A main object of the present invention is to provide a foldable side support arrangement for a foldable furniture, wherein two side portions of the tension fabric are well supported by the foldable frame such that the foldable furniture is more comfortable and capable of supporting more weight in comparison with the conventional foldable furniture that has the same frame structure and size. 
     Another object of the present invention is to provide a foldable side support arrangement for a foldable furniture which substantially increases the supporting area of the tension fabric to more evenly distribute and support the downward force and stress applied on the tension fabric. 
     Another object of the present invention is to provide a foldable side support arrangement for a foldable furniture, wherein two side portions of the tension fabric are substantially supported by two foldable side supporting arm respectively in such a manner that the tension fabric allows a greater downward pulling force, such as the user&#39;s weight, applied on the tension fabric without distorting the shape thereof. 
     Another object of the present invention is to provide a foldable side support arrangement for a foldable furniture, wherein the two side supporting arms do not increase the ordinary size of the foldable furniture. Therefore, the foldable furniture of the present invention is adapted for being folded into a compact unit for carriage and storage and unfolded for use as usual. 
     Accordingly, in order to accomplish the above objects, the present invention provides a foldable furniture, comprising: 
     a foldable frame, which comprises: 
     two side frames each comprising a first side frame leg and a second side frame leg pivotally coupled with each other to form a “X” structure; 
     a front frame comprising a first front frame leg and a second front frame leg pivotally coupled with each other to form a “X” structure; 
     a rear frame comprising a first rear frame leg and a second rear frame leg pivotally coupled with each other to form a “X” structure; 
     a pair of front frame joints pivotally connected two upper ends of the front frame legs with two upper ends of the side frame legs respectively; and 
     a pair of rear frame joints pivotally connected two upper ends of the rear frame legs with two upper ends of the side frame legs respectively; and 
     a foldable side support arrangement, which comprises: 
     a pair of side supporting units each comprising a first and second side supporting arms pivotally connected with each other end to end wherein a free end portion of the first side supporting arm is pivotally coupling with the upper end of the respective second side frame leg and a free end portion of the second side supporting arm is pivotally coupling with the upper end of the respective first side frame leg; 
     a pair of retaining units coupling with the side supporting units respectively to reinforce the side supporting units pivotally extended to retain the first and second side frame legs in position when the foldable frame is unfolded to stretch out; and 
     a tension fabric, which is supported on the foldable frame, having two side edge portions substantially supported by the two side supporting units respectively. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a foldable furniture incorporated with a foldable side support arrangement according to a first preferred embodiment of the present invention. 
     FIG. 2 is the foldable side support arrangement of the foldable furniture according to the above first preferred embodiment of the present invention. 
     FIG. 3 is a side view of the foldable furniture with the foldable side support arrangement according to the above first preferred embodiment of the present invention. 
     FIG. 4 is a view of the foldable furniture in a folded position according to the above first preferred embodiment of the present invention. 
     FIG. 5 is a perspective view of a foldable furniture incorporated with a foldable side support arrangement according to a second preferred embodiment of the present invention. 
     FIG. 6 is a side view of the foldable furniture with the foldable side support arrangement according to the above second preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1 of the drawings, a foldable furniture  1  incorporated with a foldable side support arrangement  20  according to a first preferred embodiment of the present invention is illustrated, wherein the foldable furniture  1  of the first embodiment, which is constructed as a foldable table, comprises a foldable frame  10  to support a tension fabric  23  thereon. 
     The foldable frame  10 , such as a conventional foldable table frame, comprises two side frames  11  each comprising a first side frame leg  111  and a second side frame leg  112  pivotally coupled with each other to form a “X” structure, a front frame  12  comprising a first front frame leg  121  and a second front frame leg  122  pivotally coupled with each other to form a “X” structure, and a rear frame  13  comprising a first rear frame leg  131  and a second rear frame leg  132  pivotally coupled with each other to form a “X” structure. 
     The foldable frame  10  further comprises a pair of front frame joints  14  pivotally connected two upper ends of the front frame legs  121 ,  122  with two upper ends of the side frame legs  111  respectively and a pair of rear frame joints  15  pivotally connected two upper ends of the rear frame legs  131 ,  132  with two upper ends of the side frame legs  112  respectively. 
     The foldable frame  10  further comprises four base joints  161 ,  162 ,  163 ,  164 , wherein the first and second base joints  161 ,  162  pivotally connect two bottom ends of the side frame legs  112  with two bottom ends of the front frame legs  121 ,  122  respectively and the third and fourth base joints  163 ,  164  pivotally connect two bottom ends of the side frame legs  111  with two bottom ends of the rear frame legs  131 ,  132  respectively. 
     As shown in FIG. 2, the foldable side support arrangement  20  comprises a pair of side supporting units  21  and a pair of retaining units  22  coupling with the side supporting units  21  respectively to reinforce the side supporting units  21  pivotally extended to retain the first and second side frame legs  11 ,  12  in position when the foldable frame  10  is unfolded to stretch out. 
     Each of the side supporting units  21  comprises a first and second side supporting arms  211 ,  212  pivotally connected with each other end to end wherein a free end portion of the first side supporting arm  211  is pivotally coupling with the upper end of the respective second side frame leg  112  and a free end portion of the second side supporting arm  212  is pivotally coupling with the upper end of the respective first side frame leg  111 . 
     The tension fabric  23 , which is supported on the foldable frame  10 , has two side edge portions  231 ,  232  substantially supported by the two side supporting units  21  respectively. 
     According to the preferred embodiment, the first and second side supporting arms  211 ,  212  of each of the side supporting units  21  are pivotally connected by a pivot joint  24  in such a manner that the first and second side supporting arms  211 ,  212  are adapted to be pivotally folded between a folded position and an unfolded position. In which, at the folded position, the foldable frame  10  is collapsed while the first and second supporting arms  211 ,  212  are pivotally folded downwardly toward with each other. At the unfolded position, the foldable frame  10  is fully expanded to form a box shaped structure by the two side frames  11 , the front frame  12 , and the rear frame  13  while the first and second side supporting arms  211 ,  212  are pivotally and upwardly folded in a horizontal position to retain the foldable frame in an unfolded stretching manner. 
     It is worth to mention that the free end portion of the first side supporting arms  211  is adapted to pivotally connect to the rear frame joint  15  where the upper end of the respective second side frame leg  112  is pivotally connected thereto and the free end portion of the second side supporting arms  212  is adapted to pivotally connect to the front frame joint  14  wherein the upper end of the respective first side frame leg  111  is pivotally connected thereto, in such a manner that the first and second side supporting arms  211 ,  212  are adapted to pivotally fold in the horizontal position to retain a distance between the front and rear frame joints  14 ,  15  when the foldable frame  10  is unfolded. 
     Accordingly, a total length of the first and second side supporting arms  211 ,  212  of each of the side supporting units  21  must be at least equal to a distance between the corresponding front and rear frame joints  14 ,  15  in the unfolded position in such a manner that when the first and second side supporting arms  211 ,  212  are folded upwardly, the side supporting units  21  retain the distances between front and rear frame joints  14 ,  15  respectively so as to substantially support the foldable frame  10  in the unfolded position. 
     Referring to FIG. 2, the pivot joint  24  is constructed to have a first joint member  241  firmly affixed to the first side supporting arm  211  and a second joint member  242  firmly affixed to the second supporting arm  212  to pivotally connect with the first joint member  241 . The first and second members  241 ,  242  have first and second stopper edges  2411 ,  2421  to limit a pivotal movement of thereof. In other words, the first joint member  241  is pivotally connected to the second joint member  242  while the first stopper edge  2411  of the first joint member  241  is arranged to limit a pivotal movement of the second joint member  242  and the second stopper edge  2421  of the second joint member  242  is arranged to limit a pivotal movement of the first joint member  241 , so that the first and second side supporting arms  241 ,  242  are allowed to upwardly fold in a horizontal position when the foldable frame  10  is unfolded. 
     As shown in FIGS. 1 and 3, since the two side supporting units  21  are extended along the two side portions of the tension fabric  23  respectively, the tension fabric  23  is stretched by the two side supporting units  21  in a tense manner. Therefore, when the foldable frame  10  is unfolded, the side supporting units  21  can more evenly distribute and support the downward force and stress applied on the tension fabric  23 , so that the user is allowed to put more weight on the foldable furniture  1  without distorting the shape of the tension fabric  23 . 
     As shown in FIG. 2, each of the retaining unit  22  comprises a standing leg  221  having an upper pivot end  2211  pivotally connected to the first side supporting arm  211  and a bottom supporting end  2212  downwardly extended for biasing the ground when the foldable frame  10  is in the unfolded position. 
     Each of the standing legs  221  has a predetermined height with respect to a height of the foldable frame  10  in the unfolded position in such a manner that when the foldable frame  10  is in the unfolded position, the standing legs  221  are adapted to substantially support the side supporting units  21  respectively, so as to prevent the first and second side supporting arms  211 ,  212  of the side supporting units  21  folding downwardly. 
     It is worth to mention that in the unfolded position, the supporting end  2212  of the standing leg  221  is substantially biased against the ground, such that the pivotal movements of the first and second side supporting arms  211 ,  212  are locked up so as to prevent the side supporting unit  21  from being folded up accidentally. 
     Moreover, each of the standing legs  221  further comprises a ground rest  2213  affixed to the supporting end  2212  of the standing leg  221  for enhancing the stabilization of the foldable frame  10  when the ground rest  2213  biases on the ground. 
     Each of the retaining unit  22  further comprises a guiding holder  222  arranged to guide the respective standing leg  221  between the folded position and the unfolded wherein the guiding holder  222  comprises a tubular slider body  2221  and a connecting wing  2222  integrally extended from the slider body  2222 . Each of the slider bodies  2221  is rotatably mounted on a predetermined position of the side frame  11  by pivotally riveting the connecting wing  2222  to the side frame  111 , wherein the slider body  2221  has an axial slider through slot  2223  which has a diameter slightly larger than a diameter of the respective standing leg  221  for the standing leg  221  slidably passing through, as shown in FIG.  2 . 
     Accordingly, the connecting wing  2222 , which is integrally extended from one side of the slider body  2221 , is pivotally riveted to the side frame  11  at a position that where the first and second side frame legs  111 ,  112  are pivotally connected with each other. 
     The guiding holder  222  is arranged to guide the standing leg  221  in a vertically movable manner between the folded position and the unfolded position. When the foldable frame  10  is folded up, the first and second side frame legs  111 ,  112  are pivotally folded toward each other while the standing leg  221  is upwardly slid along the guider holder  222  so as to lift up the supporting end  2212  of the standing leg  221 , as shown in FIG.  4 . When the foldable frame  10  is unfolded, the pivotal movements of the first and second side frame legs  111 ,  112  force the standing leg  221  sliding downwardly through the guiding holder  222  until the supporting end  2212  of the standing leg  221  biases on the ground, as shown in FIG.  3 . It is worth to mention that the standing leg  221  is mounted to the side frame  11  in a vertically movable manner, the unfolded size of the foldable frame  10  will not increased after incorporating with the retaining unit  23 . 
     The tension fabric  23  further comprises a pair of holding devices  231  holding the two side portions of the tension fabric  23  with the side supporting units  21  respectively. Each of the holding devices  231  comprises at least a tubular holding sleeve  2311 , having two open ends, provided on each side portion of a bottom surface of the tension fabric  23  in such a manner that one of the first and second side supporting arms  211 ,  212  is arranged to slidably pass through the tubular holding sleeve  2311  of the holding device  231 . As shown in FIGS. 1 and 3, there are two tubular holding sleeves  2311  of the holding device  231  provided on each of the side portions of the bottom surface of the tension fabric  23  for the first and second side supporting arms  211 ,  212  slidably passing through, so as to substantially mount the tension fabric  23  on the foldable frame  10 . 
     As shown in FIG. 3, the tension fabric  23  further has two pairs of tubular holding pocket  232 , each having an open end, provided at comer portions of the bottom surface of the tension fabric  23  respectively in such a manner that the free end portions of the first and second side supporting arms  211 ,  212  are arranged to slidably insert into the holding pockets  232  respectively, so as to tensely retain the tension fabric  23  by the side supporting units  21 . 
     Practically, the downward force applied on the tension fabric  23  has a trend of pulling the two side supporting units  21  towards each other. However, each of the side supporting units  21  is substantially retained between the front and rear frame joints  14 ,  15  such that the downward force will be evenly distributed to the foldable frame  10  through the side supporting units  21 . In other words, the side supporting units  21  can enhance the tension of the tension fabric  23  by reinforcing the two side portions thereof, that substantially increase the effective supporting contact-area of the tension fabric  23 . Therefore, the foldable furniture  1  is capable of supporting more weight in comparison with the conventional furniture without the foldable side support arrangement  20 . 
     Referring to FIG. 5, a foldable furniture  1 ′ according to a second embodiment illustrates an alternative mode of the first embodiment of the present invention, wherein the foldable furniture  1 ′ of the second embodiment, which is embodied as a foldable bed, is a modification of the first embodiment. 
     As shown in FIGS. 5 and 6, the foldable furniture  1 ′ comprises two identical foldable frames  10 ′ connected with each other by integrally connecting the front frame joints  14 ′ of the first and second foldable frames  10 ′ together to form a foldable bed frame  101 ′. Moreover, the two foldable frames  10 ′ share with one front frame  12 ′ which comprises the first and second front frame legs  121 ′,  122 ′. 
     Each of the foldable frame  10 ′ comprises the foldable side support arrangement  20 ′ wherein the two pairs of side supporting units  21 ′ are pivotally extended at two sides of the foldable bed frame  101  ′ while the free end portion of each first side supporting arm  211 ′ is pivotally connected to the respective front frame joint  14 ′ and the free end portion of each second side supporting arm  212 ′ is pivotally connected to the rear frame joint  15 ′. 
     The tension fabric  23 ′, which is supported on the foldable bed frame  101 ′, has two side portions supported by the side supporting units  21 ′ respectively in such a manner that the tension fabric  23 ′ is stretched by the side supporting units  21  in a tense manner when the foldable bed frame  101 ′ is unfolded to stretch out. Besides, the downward pulling force applied by the user′ weight will distribute from the tension fabric  23 ′ to the entire foldable bed frame  101 ′ so that the foldable bed is more comfortable and capable of supporting more weight in comparison with the conventional foldable bed having the same foldable bed frame structure and size. 
     Accordingly, the tension fabric  23 ′ comprises two pairs of holding devices  231 ′ to hold the two side portions of the tension fabric  23 ′ with the side supporting units  21 ′ respectively, wherein each of the holding devices  231 ′ comprises at least the tubular holding sleeve  2311 ′, having two open ends, provide on each side portion of the bottom surface of the tension fabric  23 ′ for the first and second side supporting arms  211 ′,  212 ′ of each of the side supporting units  21 ′ slidably passing through, so as to mount the tension fabric  23 ′ on the side supporting units  21 ′ to evenly distribute the downward force on the tension fabric  23 ′ through the entire foldable bed frame  101 ′. 
     The tension fabric  23 ′ further has two pairs of tubular holding pockets  232 ′, each having an open end, provided at corner portions of the bottom surface of the tension fabric  23 ′ in such a manner that the free end portions of the second side supporting arms  212 ′ are arranged to slidably insert into the holding pockets  232 ′ respectively, so as to tensely retain the tension fabric  23 ′ by the side supporting units  21 ′. 
     When the foldable bed frame  101 ′ is unfolded to stretch out, as shown in FIG. 6, each of the guiding holder  222 ′ is arranged to guide the respective standing leg  221 ′ in a vertical manner, such that the supporting end  2212 ′ of each standing leg  221 ′ is substantially biased against the ground, so as to substantially support the foldable bed frame  101 ′ through the side supporting units  21 ′.