Patent Publication Number: US-2018027970-A1

Title: Folding chair with back rest

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention is to a new design used in the leisure chairs field, especially for a kind of folding chair with back, particularly for a kind of foldable, flat-folding stool. 
     SUMMARY OF THE INVENTION 
     Two sides of two rectangular frames become an X cross-hinge, and the folding stool formed is at once an ancient and commonly seen stool, especially in that the stool surface uses a soft fabric or strap, enabling the structure to be more simple. Additionally, when sitting it is possible to choose two cross hinges that join into a forward and back part. In this way the legs will not be obstructed by the rectangular frame horizontal bars, and therefore sitting is more comfortable, but without using the back rest. For this, the manufacturers add back rest rectangular frames, creating a folding stool that has back rest functionality. The structure has a small rectangular frame, a large rectangular frame, and a back rest rectangular frame. The three can be nested to stack together into a flattened shape. In this, the small rectangular frame and the large rectangular frame&#39;s two sides cross-hinge together, forming a cross-support. On the large and small rectangular frames between the horizontal bars has been placed a soft fabric; the back rest rectangular frame&#39;s bottom end hinges on the large rectangular frame&#39;s top two outside faces. The backrest rectangular frame&#39;s bottom section horizontal bars are located behind the rectangular frame&#39;s back side, providing support for the back rest. The back rest rectangular frame has a back rest fabric which is held tightly, and provides back rest functionality. When folding, one only need to move the rectangular frame back and it will fold together with the large and small rectangular frames. The described small rectangular frame, large rectangular frame, and the back rest rectangular frame, can be a closed rectangular frame, an open rectangular frame, or U-shaped bars. How to improve this classic structure&#39;s stool with back rest has become a new area for utility research. The horizontal bars of the large and small rectangular frames of the stool with back rest located to the front and the back, especially the front horizontal bar which precisely protrudes into the area for the legs, and lacks in comfort. This promotes a new kind of objective which is to design a kind of U-shaped bar with two corners that narrow into horizontal bars with a short length, opening the soft stool surface to form a trapezoid shape, and the two front corners provide space in the folding chair with back for the legs to be placed in that space. 
     This is used for a new technique presented herein and is achieved as follows: 
     The present design uses a new objective, which is to design a kind of U-shaped bar with two corners that narrow into horizontal bars with a short length, opening the soft stool surface to form a trapezoid shape, and the two front corners provide space in the folding chair with back for the legs to be placed in that space. 
     This is used for a new technique, which is achieved as follows: A kind of folding chair with back, includes large and small U-shaped bars and a back rest U-shaped bar. The two sides of the short vertical bar on the small U-shaped bar and the large U-shaped bar form support with the cross-hinged long vertical bar. On the soft stool surface is placed the U-shaped bars&#39; short horizontal bar and large U-shaped bars&#39; large horizontal bar. The backrest U-shaped bars&#39; two backrest vertical bars&#39; are hinged to the large U-shaped bars&#39; two vertical bars&#39; top end, and the backrest horizontal bars are located on the previously discussed vertical bars&#39; back surface, forming a weight support. The large U-shaped pole as described above is a tripartite composition (or “arrangement”), which includes two long vertical poles and one connecting U-shaped pole. The two ends of the connecting U-shaped pole are hinged on the long vertical poles respectively. The U-shaped pole of the backrest contains two vertical poles and each of them is hinged on the top of the long vertical poles correspondingly. The horizontal pole of the backrest directly makes contact with the backside of the large U-shaped pole, which provides support. 
     The discussed stopper uses a tube clip positioned on the U-shaped bars&#39; long vertical bars, and the tube clip is provided with a 180-degree ring groove. The ring groove&#39;s two end points are designed with limiting grooves. A screw goes through the discussed ring groove to affix it on to the vertical bars, and the stopper and tube clip both wrap around the long vertical bars in a 180-degree spiral. 
     The soft stool surface and back rest fabric both have a structure that can provided double-sided usages. 
     The front and back ends of the discussed soft stool surface has stitches into place handles, and the handles can be hooked together. 
     This uses a new small U-shaped bar two corner narrowing structure, which creates definite space in the two corners, so that if the legs extend out in a seated position, it avoids the short horizontal bar top from blocking the legs, which is very comfortable and relaxing. The supported trapezoidal soft stool surface changes the traditional four sided stool surface which did not change, and can also provide perfect support for a person&#39;s gluteal; through a spiral stopper design, and thus it is possible to achieve a two-sided use characteristic for a stool with back rest; 
     After being folded, the backrest U-shaped bars, large U-shaped bars and U-shaped bars together are nested into a flat surface, and the stopper can also rotate 90 degrees, being placed in the corner of the collapsed area in the U-shaped bars, saving storage space. 
     The front and back ends of the discussed soft stool surface has stitches to place handles, and the handles can be hooked together. 
     The following combines the specific designs for the use of this new model as are further explained: The supported trapezoidal soft stool surface changes the traditional four sided stool surface which did not change. It can also provide perfect support for people&#39;s gluteal; through a spiral stopper design, to achieve a two-sided use characteristic for a stool with back rest. After being folded, the backrest U-shaped bars, large U-shaped bars and U-shaped bars together are nested into a flat surface, and the stopper can also rotate  90  degrees, being placed in the corner of the collapsed area in the U-shaped bars, thereby saving storage space. 
     These and other objects of the present invention will be readily apparent upon review of the following detailed description of the invention and the accompanying drawings. These objects of the present invention are not exhaustive and are not to be construed as limiting the scope of the claimed invention. Further, it must be understood that no one embodiment of the present invention need include all of the aforementioned objects of the present invention. Rather, a given embodiment may include one or none of the aforementioned objects. Accordingly, these objects are not to be used to limit the scope of the claims of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic of a folding stool with a back rest according to a first preferred embodiment. 
         FIG. 2  is a schematic diagram of the frame of the chair of  FIG. 1 . 
         FIG. 3  is a schematic diagram showing a folding demonstration of the foldable stool with backrest of  FIG. 1  into a stored position. 
         FIG. 4  is an alternative, front plan view of the chair of  FIG. 3 . 
         FIG. 5 : is a schematic diagram for the support mechanism of the foldable stool with backrest according to a second, preferred embodiment. 
         FIG. 6  is an exploded view of I part in  FIG. 5   
         FIG. 7  is a schematic diagram for the support mechanism of the foldable stool with backrest of the stool of  FIG. 5 . 
     
    
    
     Among these figures, the following parts are shown:
       1 —Small U-shaped bars     11 —Short Vertical Bar     12 —short horizontal bar     2 —Large U-shaped bars     21 —Long vertical bars     22 —Long horizontal bar     23 —connecting U-shaped pole     3 —backrest U-shaped bars     31 —backrest vertical bars     32 —backrest horizontal bars     4 —soft stool surface     41 —handles     5 —back rest fabric     6 —stopper     61 —tube clip     62 —ring groove     63 —limiting groove   

     Similar reference characters denote corresponding features consistently throughout the attached drawings. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
     Referring now to  FIGS. 1 through 4 , the folding chair with back includes small U-shaped bars, large U-shaped bars  1 , and back rest U-shaped bars  3 . The three bars gradually open up, and can be nested together, forming a flat folded shape. 
     The small U-shaped bars  1  have two corners that are a narrowing structure, and compact into short length short horizontal bars  12 , as in  FIG. 4 . And to be more specific, when the two corners of the small U-shaped bars compact, the short horizontal bar  12  with a length of A is a small U-shaped bar with two short vertical bars  11  with a distance of B apart that is between ⅓ and ⅔, and ½ is the best, and can avoid leaving space for the legs. 
     Aside from the U-shape structure, at least the small U-shaped bars  1  and large U-shaped bars  2 , can still use the U-shaped main rectangular frame opening and rectangular frame replacement, and likewise can completely achieve a new type of task, using the rectangular frames or opening the rectangular frame structure, and still are part of the use or new model protection series. The small U-shaped bars  1  and large U-shaped bars  2  on two sides have a short vertical bar  11  and vertical bars  21  that are cross-hinged to form support, which is to say that when opened, they form an X-shaped cross support. 
     Between the U-shaped bars&#39; short horizontal bar  12  and the U-shaped bars&#39; horizontal bar, is placed a soft stool surface  4  in a trapezoid structure, which allows for providing good support for the human buttocks, satisfying the need for support of the body&#39;s weight. The two front corners, upon being compacted, will not protrude into the legs, making the seating comfortable. 
     The backrest U-shaped bars&#39;  3  has two backrest vertical bars  32  which correspond to two hinged large U-shaped bars on two long vertical bars  21  on their top side, and the backrest horizontal bars  32  are located on the back side of the vertical bars  21 , forming a back weight support, and can wrap this hinge point towards the front and be rotated, forming a collapsed shape. 
     Between two backrest vertical bars  31  are a tightened back rest fabric  5 . In principle, the backrest U-shaped bars use rectangular frames or open rectangular frames, and there are three reasons for this: The first is to save on material; the second is that the backrest vertical bars need not be too high, which means that when they are completely collapsed; and third, the three do not have a top end horizontal bar obstructing the back, but leaning on it is more comfortable. In order to adjust the back so the human body will be able to lie at a titled angle comfortably, it can be considered to make the stool service the center of gravity, as current technology will bend the backrest vertical bars  31  close to the backrest horizontal bars  32 , allowing the backrest horizontal bars  32  to directly lean on the large U-shaped bars&#39; long vertical bars  21 . 
     In this way the result is to collapse the back folding stool thickness making it much thicker, by adjusting the position of the hinge joints or apply and change the rotatable stopper  6  to solve this problem, and the specific structure is as below: The first solution is to adjust the position of the hinge joints: as illustrated in  FIG. 1-4 , the large U-shaped pole (# 2 ) is a tripartite composition, which includes two long vertical poles (# 21 ) and one connecting U-shaped pole (# 23 ). The two ends of the connecting U-shaped pole (# 23 ) are hinged on the two long vertical poles (# 21 ) respectively. The U-shaped pole of the backrest (# 3 ) contains two vertical poles (# 31 ) and each of them is hinged on the top of the two long vertical poles (# 21 ) correspondingly. The horizontal 
     pole of the backrest (# 32 ) directly makes contact with the backside of the large U-shaped pole (# 2 ), which provides support. To be more specific, the composition of the large U-shaped pole (# 2 ) is extended to allow the two long vertical poles (# 21 ) to hinge onto the U-shaped pole of the backrest (# 3 ), which leads to an ideal ergonomic backrest angle as the horizontal pole of the backrest (# 22 ) makes contact with the backside of the large U-shaped pole (# 2 ). Because of the narrowing of both sides of the small U-shaped pole (# 1 ), there is sufficient space for the connecting U-shaped pole (# 23 ), as illustrated in  FIG. 4 . The design does not affect the folding function of the foldable stool. In addition, each of the small U-shaped pole (# 1 ), the large U-shaped pole (# 2 ) and the U-shaped pole of the backrest (# 3 ) utilizes a single axle hinge, which not only allows the stool to fold remarkably flat, but also allows the U-shaped pole of the backrest (# 3 ) to rotate freely. As a result, the foldable stool can be used on both sides. 
     The second solution is to utilize the rotating stoppers: according to  FIGS. 5, 6 and 7   
     Between two backrest vertical bars  31  is a tightened back rest fabric  5 . In principle, the backrest U-shaped bars use rectangular frames or open rectangular frames, and there are three reasons for this: The first is to save on material; second is that the backrest vertical bars need not be too high, which means that when they are completely collapsed, and third the three do not have a top end horizontal bar obstructing the back, but leaning on it is more comfortable. 
     A screw  7  is placed through the ring groove  62  secured on the long vertical bars  21 , and the stopper  6  and tube clip  61  together can wrap around the vertical bars  21  to make a 180-degree revolution. In this way the soft stool surface  4  and back rest fabric  5  can be twisted around to be used. Additionally, when collapsed the stopper  6  and tube clip  61  rotate  90  degrees, and then can be effectively turned to the inside of the long vertical bars, and incidentally is located in the small U-shaped bars&#39;  1  corners and collapsed and leaves space, and will not take up the available space for thickness. 
     Further, due to the fact that the stopper  6  rotates, it can achieve rotational use for the stool with back rest, and for this the soft stool surface  4  and back rest fabric  5  each have a structure that can provide two surfaces. The  6  stopper uses a  61  tube clip positioned on the U-shaped bars&#39;  21  long vertical bars, and the  61  tube clip is provided with a 180 degree  62  ring groove. The  62  ring groove&#39;s two end points are designed with limiting grooves  63 . A screw  7  is placed through the ring groove  62  secured on the long vertical bars  21 , and the stopper  6  and tube clip  61  together can wrap around the vertical bars  21  to make a 180-degree revolution, and in this way the soft stool surface  4  and back rest fabric  5  can be twisted around to be used. Additionally, when collapsed, the stopper  6  and tube clip  61  rotate  90  degrees, and then can be effectively turned to the inside of the long vertical bars, and incidentally is located in the small U-shaped bars&#39;  1  corners and collapsed and leaves space, and will not take up the available space for thickness. 
     Further, due to that the stopper  6  rotates, it can achieve rotational use for the stool with back rest the backrest can be rotated and both sides of the foldable stool can be used as well, and for this the soft stool surface  4  and back rest fabric  5  each have a structure that can provide two surfaces, as shown in  FIG. 1  and  FIG. 3 ; considering that the folding stool for the most part is used as a temporary chair, the backrest U-shaped bars&#39; two backrest vertical bars  31  are somewhat short, and when expanding the chair for use, it may be blocked by the back rest fabric  5 . At this time it is only necessary to take off the back rest fabric  5 , and twist it to the proper position, and the back rest fabric  5  will use a sheath positioned at the two ends of the backrest vertical bars. 
     Additionally, the soft stool surface  4  front and back end have stitches for handles  41 . The two handles  41  can be hooked together, and when hooked together will not only facilitate carrying, it also can be compacted and nested together with the short horizontal bar  12 , back rest horizontal bar  22 , and back rest horizontal bar  32 , killing two birds with one stone. The links can be tied together, magic knots, or chain linked, among other commonly seen linking methods. 
     While this invention has been described as having a preferred design, it is understood that it is capable of further modifications, uses and/or adaptations of the invention following in general the principle of the invention and including such departures from the present disclosure as come within the known or customary practice in the art to which the invention pertains and as maybe applied to the central features hereinbefore set forth, and fall within the scope of the invention and the limits of the appended claims. It is therefore to be understood that the present invention is not limited to the sole embodiment described above, but encompasses any and all embodiments within the scope of the following claims.