Abstract:
A bellows design and a method of making such a bellows design are disclosed. The method of producing a folding bellows is simple in construction, utilizes assembly methods which are not complex, uses inexpensive materials, and provides protection similar to more complicated and expensive bellows. The bellows construction uses two basic components, a flat piece of flexible material and formed frame which are used in conjunction with each other to produce the folding bellows.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is based on and claims priority to U.S. Provisional Patent Application No. 61/664,275 filed on Jun. 26, 2012, which is incorporated herein by reference in its entirety for all purposes. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to the field of protective covers. More particularly, the present invention relates to the design and construction of a folding bellows. 
       BACKGROUND 
       [0003]    Folding bellows are used to protect many items that move and need to be protected throughout a range of movement. Bellows are typically used to prevent items from getting into an area that needs to be protected. Some examples of the use of bellows are to protect machinery from industrial hazards such as metal chips or other debris, to protect outdoor equipment from environmental hazards such as rain or snow, or to provide a transport route for air or powder. Bellows are also frequently used to prevent people from accessing the interior of equipment that may cause harm such as a scissors type lifting device. 
         [0004]    There are many methods of manufacturing such bellows but it has been standard in the industry to have the bellows produced in such a manner as to create panels and hinges in some manner such that the entire bellows can allow for extending to an open position or retracting to a closed position and be able to repeat this movement while maintaining the original shape. The shape is defined by the manner in which the panels fold together. 
         [0005]    One method of producing a bellows is to use flexible fabric and alternately stitch together the inside and outside edges thus creating hinges at the inside and outside and allowing the fabric portion between the stitched edges to act as the panel. This construction may be enhanced by stitching in plastic or metallic rods at either of, or both of, the material edges. See, for example, U.S. Pat. No. 4,579,045. 
         [0006]    Another method of producing a bellows is to laminate many plies of materials and material strips together while leaving a small gap between the material strips. When the laminated sheet is folded, the gaps act as the hinges and the strips act as the panels. See, for example, U.S. Pat. Nos. 5,021,271; 4,745,848; and 4,638,722. A similar method of producing a bellows is to produce a sheet that utilizes a rigid plastic panel that alternates with a flexible plastic hinge to create the folding mechanism. See, for example, U.S. Pat. Nos. 4,662,734 and 6,986,938. 
         [0007]    Yet another method of producing a bellows is to create a plastic or metallic frame to which flexible material is attached. The material then folds itself between frame members. The frame members are typically located at the exterior of the bellows shape. Each of these methods of manufacturing a folding bellows are costly to produce due to the assembly method needed to create the folding panel and hinge structure, the amount of material that is needed to produce the folding structure, or the time that is needed to produce the folding structure. 
         [0008]    As such, there is a need for a method of manufacturing a folding bellows that will provide a similar function as other folding bellows but designed in such a manner as to reduce the cost by simplifying the method of manufacturing and reducing the amount and type of material used. 
       SUMMARY 
       [0009]    The present invention relates to a bellows having a covering panel formed into a continuous generally tube shape by securing an end thereof to another end thereof. The bellows includes a plurality of U-shaped channel frames having jaws for receiving and securing portions of the covering panel. The U-shaped channel frames are located inside the tube shape and are secured to two opposing sides of the covering panel to create a formed folding shape leaving two sides adjacent the formed folding shape sides as floating sides. 
         [0010]    In an alternative embodiment, the bellows includes a plurality of outer frames that are secured to the outer surface of the tube shape. Frame stiffeners are inserted into each channel frame on the floating sides and connect the channel frames to the outer frames thereby trapping the tube shape inside the outer frames. 
         [0011]    It will be understood by those skilled in the art that one or more aspects of this invention can meet certain objectives, while one or more other aspects can lead to certain other objectives. Other objects, features, benefits and advantages of the present invention will be apparent in this summary and descriptions of the disclosed embodiment, and will be readily apparent to those skilled in the art. Such objects, features, benefits and advantages will be apparent from the above as taken in conjunction with the accompanying figures and all reasonable inferences to be drawn therefrom. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is a perspective view that depicts one embodiment of a folded bellows in accordance with the invention shown in a retracted position; 
           [0013]      FIG. 2  is a perspective view of the folded bellows of  FIG. 1  shown in an extended position; 
           [0014]      FIG. 3  is another perspective view of the folded bellows of  FIG. 1  showing two adjacent sides of the folding bellows; 
           [0015]      FIG. 4  is another perspective view of the folded bellows of  FIG. 1  showing the inside of two adjacent sides of the folding bellows; 
           [0016]      FIG. 5  is a top view of the folded bellows of  FIG. 1  with dashed lines indicating the position of the forming frame pieces; 
           [0017]      FIG. 6  is a section view of the folded bellows of  FIG. 1  taken generally along the line  6 - 6  of  FIG. 5  showing the folding bellows in a retracted position; 
           [0018]      FIG. 7  is a section view of the folded bellows of  FIG. 1  taken generally along the line  6 - 6  of  FIG. 5  showing the folding bellows in an extended position; 
           [0019]      FIG. 8  is a section view of the folded bellows of  FIG. 1  taken generally along the line  8 - 8  of  FIG. 5  showing the folding bellows in a retracted position; 
           [0020]      FIG. 9  is a section view of the folded bellows of  FIG. 1  taken generally along the line  8 - 8  of  FIG. 5  showing the folding bellows in an extended position; 
           [0021]      FIG. 10  is a perspective view of another embodiment of a folded bellows in accordance with the invention showing the folded bellows in an extended position; 
           [0022]      FIG. 11  is a top view of the folded bellows of  FIG. 10  with dashed lines indicating the position of the forming frame pieces; 
           [0023]      FIG. 12  is a section view of the folded bellows of  FIG. 10  taken generally along the line  12 - 12  of  FIG. 11  showing the folding bellows in a retracted position; 
           [0024]      FIG. 13  is a section view of the folded bellows of  FIG. 10  taken generally along the line  12 - 12  of  FIG. 11  showing the folding bellows in an extended position; 
           [0025]      FIG. 14  is a section view of the folded bellows of  FIG. 10  taken generally along the line  14 - 14  of  FIG. 11  showing the folding bellows in a retracted position; and 
           [0026]      FIG. 15  is a section view of the folded bellows of  FIG. 10  taken generally along the line  14 - 14  of  FIG. 11  showing the folding bellows in an extended position. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    Turning now to  FIGS. 1-9 , one embodiment of a folding bellows  100  in accordance with the invention shown. The folding bellows  100  is designed and manufactured in such a manner that involves a flat piece of flexible material  102  and a plurality of forming frames  104 . In the embodiment shown, the flat piece of flexible material  102  is one single sheet that is formed into a tube shape by adhering one end to another with a seam. The tube shape may also be assembled with multiple smaller pieces of flexible material  102  but with the same resulting tube shape that is created if a single piece of material is used. Alternatively, if the folding bellows  100  has a zipper or similar closure, or the folding bellows are not completely enclosed (i.e. three sided), a tube will not need to be created. Additionally, the flexible material  102  can be any type of flexible material including, but not limited to thermoplastic, elastomer, or thermoplastic elastomer film or coated fabric. 
         [0028]    The forming frames  104  that are used in this design have a U-shaped cross section, and have a jaw  106  that can receive the flexible material  102  from which the tube is made.  FIGS. 6-7  are cross-sectional views that show how the flexible material  102  is received in the jaw  106 .  FIG. 6  shows the folding bellows  100  in a collapsed position, and  FIG. 7  shows the folding bellows in an extended position. The forming frames  104  can also be a continuous solid shape or another shape which is capable of connecting it to the flexible material  102 . The connection means may be by bonding, wrapping, sealing, crimping, or other method to fix each forming frame  104  to the flexible material  102 . 
         [0029]    The forming frames  104  are fixed to the flexible material  102  on just two opposing sides which will be referred to as the formed sides  108 . The forming frames  104  help create a formed folding shape on the formed sides  108  because the forming frames are fixed to the flexible material  102  on these two sides. The two sides adjacent to the formed sides  108  do not have any connection means between the flexible material  102  and the forming frames  104 . These will be referred to as the floating sides  110 . The flexible material  102  on the floating sides  110  takes its shape from the adjacent sides, the corner folding method, and from the length of flexible material on the floating sides being longer than the available length of flexible material on the formed side in the extension axis.  FIGS. 8-9  are cross-sectional views showing one of the floating sides  110 .  FIG. 8  shows the folded bellows  100  in the collapsed position, and  FIG. 9  shows the folded bellows in the extended position. By having two floating sides  110 , the time to create the folds on these sides is minimal because the folds are created simply as a function of the two formed sides  108  and not as a result of a direct creation of the folds in a manner such as stitching, bonding, or layering. The forming frames  104  extend across the floating side  110  to provide a means by which the flexible material  102  of the floating sides maintains its folds between the two formed sides  108  and also provides physical stiffness to the floating sides as a means of protection from objects coming into contact with the floating side. Each forming frame  104  is used to provide definition for one fold with the number of folds required for a given extended length determining the number of forming frames to be used. The forming frames  104  can be manufactured from any suitable material including metallic or plastic materials. The forming frames  104  may be formed to the desired bellows shape or they may be assembled from multiple pieces to create the desired bellows shape. 
         [0030]      FIGS. 10-15  show another embodiment of a folding bellows  200  in accordance with the invention. The folding bellows  200  has floating sides  202  that utilize an outer frame  204  that will connect to an inner forming frame  206 . Including the outer frame  204  helps stiffen inner forming frames  206  located inside the folding bellows  200  or to prevent the flexible material  208  from being pushed outward in instances that have internal air pressure applied to the interior of the folding bellows  200 . In the embodiment shown, a frame stiffener  210  is inserted into each inner frame  206 . The frame stiffener  210  connects the inner frames  206  to the outer frames  204  thereby trapping the flexible material  208  inside the outer frames as part of the connection process. As in the previously described embodiment, the inner forming frames  206  have a U-shaped cross section, and have jaws  212  that can receive the flexible material  208  from which the tube is made, thereby creating formed sides  214 . As shown,  FIG. 14  is a section view showing the folding bellows  200  in a collapsed position, while  FIG. 15  is another section view showing the folding bellows in an extended position. 
         [0031]    One method of manufacturing folding bellows  100 ,  200  in accordance with the invention is to identify locations on a tube of flexible material  102 ,  208  where the forming frames  104 ,  206  will connect to the flexible material. The connection method between the forming frames  104 ,  206  and the flexible material  102 ,  208  is then performed resulting in a series of forming frames that are connected to the flexible material in set positions in the perimeter of the tube and in an equal spaced means from one tube end to the other tube end. The set positions may be determined by any suitable means, including but not limited to marking, pleating, slitting, or sealing. A folding method is then used to create the folds of the folding bellows  100 ,  200 . The folds alternate from one side to the adjacent side. The folds which protrude inward on the formed side  108 ,  214  will protrude outward on the adjacent floating side  110 ,  214  and vice versa. 
         [0032]    The use of a folding bellows  100 ,  200  in accordance with the invention may commonly be used on a scissors type lift which utilizes the folding bellows to cover the scissors mechanism and to prevent people from getting injured by accidently placing a body part into the mechanism. 
         [0033]    Although the invention has been herein described in what is perceived to be the most practical and preferred embodiments, it is to be understood that the invention is not intended to be limited to the specific embodiments set forth above. Rather, it is recognized that modifications may be made by one of skill in the art of the invention without departing from the spirit or intent of the invention and, therefore, the invention is to be taken as including all reasonable equivalents to the subject matter of the appended claims and the description of the invention herein.