Patent Publication Number: US-7581504-B1

Title: Printed umbrella, umbrella cover, and method of making

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims priority to application Ser. No. 10/723,579, filed Nov. 26, 2003, which itself claims priority to provisional application Ser. No. 60/429,305, filed on Nov. 26, 2002, “Umbrella and Associated Methods.” 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to umbrellas and methods for constructing same, and, in particular, to umbrellas having printed indicia thereon. 
   2. Background of the Invention 
   Standard umbrellas comprise a frame having eight ribs extending outwardly from a center shaft. The ribs support a cover when in the open position. The cover is constructed by sewing together eight triangular pieces of material. The sewing process creates a natural curve to the cover material that allows it to conform to the shape of the frame. The cover is then tacked to the ribs along each of the eight seams. Each tack is positioned approximately 10-12 inches from the outer tip of the rib. 
   Decorated umbrellas are typically made by screen printing the triangles of material prior to sewing the triangles together onto the ribs of the eight-rib frame. This causes a design to be segmented rather than appearing unitary. 
   One umbrella having a one-piece cover is known in the art that comprises a stretchable, unseamed material glued onto a 16-rib frame. The frame is oversized and flatter than customary umbrellas, and is believed more expensive to fabricate than standard umbrellas. Further, such prior art umbrellas have a hemmed outer edge. 
   SUMMARY OF THE INVENTION 
   A first aspect of the present invention is directed to an umbrella cover. The umbrella cover of the present invention comprises a unitary piece of material that can be decorated, such as by printing, without segmentation. The cover comprises an octagonal piece of material having eight corners. The cover has eight generally triangular slits therein extending one from each corner of the octagon toward, but in spaced relation from, a center point, a point of each triangle at the inner end of the slit. The sides of each slit are sewn together to form a dart. 
   A second aspect of the present invention is directed to an umbrella. The umbrella comprises a cover as described above and a frame to which the cover is affixed. The cover is affixed to an eight-rib frame, with each dart tacked adjacent a flexion point in a rib. 
   A third aspect of the invention is directed to a method of fabricating an umbrella cover. The method comprises the steps of cutting eight generally triangular slits in an octagonal piece of material, the slits extending inward from each corner of the octagonal piece of material toward, but in spaced relation from, a center point of the material. Darts are formed by sewing together the sides of each slit. 
   A fourth aspect of the present invention is directed to a method of fabricating an umbrella. The method comprises the steps of making an umbrella cover as described above. Each dart is then tacked adjacent a flexion point in a rib of an eight-rib frame. 
   In an alternate embodiment, believed at present to represent a best mode of the umbrella of the present invention, the method of making an umbrella cover comprises the steps of folding a substantially octagonal unitary sheet of fabric in half along a line extending approximately from a midpoint of a first side to a midpoint of a second side. The second side is generally opposed to the first side. Being octagonal, the sheet has eight sides, each adjacent two sides meeting at a corner. 
   A slit is cut at each corner, each slit extending from the respective corner to an apex toward, but in spaced relation from, a centerpoint of the sheet. The slit is substantially isosceles triangular in shape. For each slit, opposing sides thereof are joined together to form darts. Finally, piping is affixed along the eight sides. 
   In a general case, one of skill in the art will appreciate that the invention is not intended to be limited to an octagonal element, and that any polygon could in principle be used with a correspondingly ribbed frame with the same technique to create an umbrella cover and umbrella. 
   The features that characterize the invention, both as to organization and method of operation, together with further objects and advantages thereof, will be better understood from the following description used in conjunction with the accompanying drawing. It is to be expressly understood that the drawing is for the purpose of illustration and description and is not intended as a definition of the limits of the invention. These and other objects attained, and advantages offered, by the present invention will become more fully apparent as the description that now follows is read in conjunction with the accompanying drawing. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a top plan view of a template for a first embodiment of an umbrella cover of the present invention. 
       FIG. 2  is a top plan view of an umbrella cover of  FIG. 1  prior to forming darts therein. 
       FIG. 3  is a bottom plan view of a portion of an umbrella of  FIG. 1 . 
       FIG. 4  is a top plan view of the folded and cut sheet of a second embodiment of the invention. 
       FIG. 5  illustrates the outside of the cover of  FIG. 4  with piping thereon. 
       FIG. 6  illustrates the inside of the cover of  FIG. 4  with piping thereon. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A description of the preferred embodiments of the present invention will now be presented with reference to  FIGS. 1-6 . 
   As stated above, a first embodiment of the invention comprises an umbrella and cover using an eight-rib frame ( FIGS. 1-3 ). An umbrella cover  10  comprises a unitary piece of material  11  as shown in  FIG. 1 , having the exemplary measurements shown thereon. The cover  10  comprises an octagonal piece of material  11  having eight corners  12 . In the embodiment shown, the material piece  11  extends 118.1 cm between diametrically opposed corners  12 , 12 ′. Each side  13  has a length  14  of 37.3 cm. 
   In a preferred embodiment, the material piece  11  comprises a woven material having substantially no elasticity, except along the bias. The material in an exemplary embodiment comprises either 75D×190T 100% nylon taffeta with acrylic coating for a screen-printed umbrella cover or 190T 100% polyester with P.U. coating for a four-color process paper transfer printing. The cutting technique preferably avoids the bias to avoid substantial stretching, which would cause uneven tension around the perimeter of the cover and an ill fit on the frame. 
   The cover  10  has eight generally triangular slits  15  therein ( FIG. 2 ) extending one from each corner  12  of the octagon  11  toward, but in spaced relation from, a center point  16 , a point  17  of each triangular slit  15  at the inner end thereof. In the embodiment shown, the slit  15  is approximately 21.6 cm long. The sides  18 , 18 ′ of each slit  15  are sewn together to form a dart  19  ( FIG. 3 ). The cover  10  is tacked  20  to an eight-rib frame  21 , with each dart  19  tacked adjacent a flexion point  22  in a rib  23 , to form a 46-inch umbrella  24 . Preferably the tacking point is approximately 8 inches from the outer tip  25  of the rib  23 . 
   The method of fabricating an umbrella  24  and cover  10  comprises the steps of cutting eight generally triangular slits in an octagonal piece of material, the slits extending inward from each corner of the octagonal piece of material toward, but in spaced relation from, a center point of the material. A desired graphic or indicia may be printed on the cover  10 , with the one-piece cover permitting the printing of a unitary graphic that does not have to be pieced together. Darts are formed by sewing together the sides of each slit. Each dart is then tacked adjacent a flexion point in a rib of an eight-rib frame. 
   A second embodiment of an umbrella cover  30  ( FIGS. 4-6 ), believed at the time of filing to represent a preferred embodiment, is made by folding a folding a substantially square sheet of fabric  31  in half along a line  32  extending approximately from a midpoint  33  of a first side  34  to a midpoint  35  of an opposed second side  36  to form two substantially equal-area rectangles. In a preferred embodiment, the sheet comprises nylon material, such as 190T nylon. Each of the two free corners  37 , 38  is then cut off to form an octagonal sheet of fabric. Alternatively, the corners  37 , 38  could be cut off prior to folding. 
   The substantially octagonal unitary sheet of fabric now has eight sides, each adjacent two sides (for example,  39 , 40 ) meeting at a corner  41 . 
   Next a slit  42  is cut at each corner, each slit extending from the respective corner  41  to an apex  43  toward, but in spaced relation from, a centerpoint  44  of the sheet. The slit  42  is substantially isosceles triangular in shape. In a particular embodiment, the slit  42  has a length approximately one-quarter a length  45  between a corner  41  and the centerpoint  44 . 
   For each slit  42 , with the sheet unfolded, opposing sides  53  thereof are then joined together to form darts  19 , for example, by sewing the slit sides  53  together. 
   In an exemplary embodiment for a standard 8-panel umbrella, dimensions are as follows: side  46  of square piece of fabric, 113 cm; side  47  of octagonal sheet, 40.2 cm; length  48  from midpoint of fold  32  to midpoint of side  40 , 55.5 cm; length  49  of slit side, 15.2 cm; base  50  of slit, 5.1 cm; and length  51  of dart, 20.3 cm. 
   Finally, piping  52  is affixed along the eight sides, for example, by sewing the piping  52  around a periphery of the cover ( FIGS. 5 and 6 ). The sewing of the piping  52  may be accomplished with the use of, for example, an edge binder pipe. Preferably the piping  52  comprises a same material as the fabric sheet, most preferably a nylon material such as 190T nylon. For the exemplary measurements given above, the piping material comprises an elongated strip 320 cm long and 2.25 cm wide. 
   The piping  52  has been found to be an important feature of this embodiment  30 , since it has been found to reinforce the cover  30 , permitting the cover  30  to be stretched to fit the frame and minimize wrinkles in the finished product. 
   In order to complete an umbrella, each dart  19  is affixed to a frame rib  23  as in  FIG. 3 . 
   It will be understood by one of skill in the art that the measurements presented herein for both embodiments  10 , 30  are exemplary, and not intended to be limiting, and that other sizes are easily contemplated by one of skill in the art, including other polygonal cover/rib number combinations, other cover materials, and other dimensions. 
   In the foregoing description, certain terms have been used for brevity, clarity, and understanding, but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such words are used for description purposes herein and are intended to be broadly construed. Moreover, the embodiments of the apparatus illustrated and described herein are by way of example, and the scope of the invention is not limited to the exact details of construction.