An umbrella is disclosed that employs an apparatus and method for attaching a canopy to an underlying support frame. In the event of strong winds, the attachment device permits the canopy to lift up off its support frame to let the air pass underneath.
Patio umbrellas are large umbrellas intended primarily for outdoor use to provide shade. The umbrella has an upstanding support pole, also known as a mast, with a lower end that rests on a support surface. At the upper end of the mast is a collapsible canopy support frame that comprises radially extending ribs and support members for holding the ribs at a desired angle.
The canopy support frame supports a canopy on the upper surfaces of its ribs. Conventional canopies typically have a pocket or other fastening means that affixes the periphery of the canopy to the ends of the ribs.
A problem with conventional patio umbrellas is that when the wind is blowing, air gets underneath the canopy, which then acts as a large sail. Strong breezes can topple the umbrella and, if used in conjunction with a patio table, topple the table as well. If the mast is securely mounted such that it can't be toppled, the strong breeze underneath the canopy can bend the canopy support frame.
An umbrella is disclosed that employs an apparatus and method for movably attaching a canopy to an underlying support frame. In the event of strong winds, the canopy can lift up off its support frame to let the air pass underneath, rather than turning the canopy into a large sail and toppling the umbrella over. After the wind passes, the canopy settles back down onto the ribs.
Stated more specifically, an umbrella is disclosed that comprises an upstanding support member and a plurality of ribs, each of the ribs having an upper surface, a first end pivotably mounted at the upper end of the support member, and a second free outer end. Each of the ribs extends radially outward from the support member. A canopy is supported by the upper surfaces of the ribs.
The disclosed umbrella further includes a plurality of flexible strips, each of the plurality of strips having a first end affixed to the upper surface of a rib and a second free end located proximate to the outer end of the rib. Each flexible strip normally extends along the upper surface of a corresponding one of the ribs.
The disclosed embodiment further includes a means for attaching the second end of the flexible strip to the lower surface of the canopy at a location proximate to the periphery of the canopy.
Referring now to the drawings, in which like numerals indicate like elements throughout the several views, an umbrella is disclosed that employs an apparatus and method for movably attaching a canopy to an underlying support frame. In the event of strong winds, the canopy can lift up off its support frame to let the air pass underneath, rather than turning the canopy into a large sail and toppling the umbrella over.
The disclosed apparatus and method for attaching the canopy to the underlying support framework can be applied to any outdoor umbrella, including a standard “market” umbrella 10, where the umbrella mast 12 is in the center of the umbrella canopy 14 with its lower end coupled to a stand 16 (
As used herein, the “mast” is the upright pole whose lower end rests on a support surface and which supports the canopy and canopy support frame. The “upstanding support member” is a pole or section of a pole to which the umbrella frame is mounted for opening and closing. In the case of a market umbrella 10, 20 as shown in
Referring to
Various means known to those skilled in the art can be used to raise and lower the canopy frame 70 and to hold the sliding collar 66 at a raised location to hold the umbrella canopy 72 in its open position. These include, without limitation, rope and pulley arrangements that move the sliding collar when a crank is turned, and spring-loaded pin arrangements by which the sliding collar can be manually lifted and, when the collar passes the spring-loaded pin, the pin pops outward to provide a support for the collar. The manner in which the canopy 72 is raised or lowered is incidental and does not impact the manner in which the canopy is mounted to the support frame 70.
Referring further to
To relieve stress on the strip 76 where it is fastened to the rib 58 by the bolt 84, an optional channel-shaped strip-retaining bracket 90 fits over the flexible strip 76 near its upper end 78. The bracket 90 is in the general shape of in inverted “U” with an upper wall 92 and sidewalls 94 depending from opposite sides of the upper wall. The sidewalls 94 of the bracket 90 fit down over the sides of the associated rib 58 until the upper channel wall 92 is imposed against the strip 76. The strip retaining bracket 90 is fastened to the rib 58 by bolts, rivets, or other suitable fastening means 95 that are inserted through the depending bracket side walls 94 and into the side walls of the rib 58.
The flexible, resilient strip 76 extends from its attachment point at the bolt 84 downward along the upper surface of the rib 58 to a lower end 96. Preferably the flexible strip 76 terminates at the end of the rib 58 or a few inches beyond.
Other means for closing the pocket opening 104 can be used, including ties, hook and loop fabric fasteners (such as that sold under the Velcro® trademark), snap fasteners, magnets, or other fastening arrangements known to those skilled in the art.
Other means for attaching the lower end 96 of the strip 76 to the canopy 72 can be used in place of a pocket 100. For example, pairs of straps can be affixed to the underside of the canopy 72. The straps can slidably affix the flexible strips to the underside of the canopy 72 by tying the ends of the straps together around the strip 76, supplying the pairs of straps with cooperating hook and loop fabric fasteners, snap fasteners, magnets, or other fastening arrangements known to those skilled in the art.
For convenience of illustration
The disclosed arrangement can be employed on a variety of different umbrella shapes, including, but not limited to, a square canopy, a hexagonal canopy, or an octagonal canopy. Further, while the disclosed embodiment 50 includes a flexible strip 76 on each rib 58, it is possible to have strips on fewer than all of the ribs.
A number of factors go into establishing the flexibility of the strip 76, including the materials used and the width and thickness of the strip. The extent to which the strip 72 can flex further depends upon the length of the strip. As previously stated, the length of the strip 72 is determined by its mounting location. From wherever along the length of the rib 58 the upper end of the strip 76 is secured, the strip should be long enough to reach the outer end of the rib or perhaps extend up to a few inches beyond. In an exemplary embodiment, the strip 76 is fiberglass, 0.125 inches thick, 0.5 inches wide, and 36 inches in length.
In addition to fiberglass, the flexible strip 76 can also be made of plastic or other flexible material that yields a similar spring constant. In adapting other materials that may inherently be more or less flexible than the disclosed fiberglass material, the stiffness of the strip 76 can be controlled by modifying its thickness, width, and cross-sectional configuration.
While the strip 76 extends along the upper edge of its associated rib 58, it does not necessarily contact the upper surface of the rib 58 for its entire length. For example, in the case of a canopy having pockets 100 into which the outer or lower ends of the strips 76 are received, the lower portion of the strip may be separated from the rib 58 by a portion of the pockets on the underside of the canopy. Similarly, after prolonged use in windy conditions, it is possible that the flexible strip 76 may begin to lose some of its resiliency and not always return to a completely straight configuration.
As used herein, the terms “strip,” “flexible strip,” “resilient strip,” “flexible, resilient strip,” and the like all refer to the same element 76. The strip must be flexible to allow it to bend when wind gets underneath the canopy, and it must also be resilient so that it will return to its original configuration after the wind subsides.
Also, while the disclosed embodiment 50 relates to a market umbrella in which the mast is centered with respect to the canopy, the canopy support frame with flexible, resilient strips can also be used in an offset umbrella such as that shown in
Finally, it will be understood that the preferred embodiment has been disclosed by way of example, and that other modifications may occur to those skilled in the art without departing from the scope and spirit of the appended claims.
The present application claims priority of U.S. provisional patent application Ser. No. 61/478,290, filed Apr. 22, 2011.
Number | Date | Country | |
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61478290 | Apr 2011 | US |