US20050247334A1

US20050247334A1 - Wind Resistant Umbrella

Info

Publication number: US20050247334A1
Application number: US10/908,127
Authority: US
Inventors: Dennis Erickson
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-05-10
Filing date: 2005-04-28
Publication date: 2005-11-10

Abstract

An umbrella comprising an upper canopy attached to a lower canopy, wherein the lower canopy is dimensioned relative to the upper canopy to increase the umbrella's resistance to high wind velocities as compared to conventional umbrellas. In this manner, the umbrella is better capable of maintaining its structural and/or its positional integrity when exposed to high wind velocities as compared to conventional umbrellas.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 60/569,082 filed on May 10, 2004.

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to umbrellas. More particularly, this invention relates to rain umbrellas, patio umbrellas, market umbrellas, beach umbrellas, awnings, and the like, wherein the umbrellas can maintain their structural and positional integrity in high wind velocity conditions.
2. Background
Conventional umbrellas generally are made with a rib support system attached to a means for extending and retracting the ribs to respectively open and close the umbrella. The umbrella has a canopy that sits on top of the ribs and is attached to the ribs at the rib end tips and at one or more points along the rib length. One problem with conventional umbrellas is that the wind can lift the underside of the canopy and force it into an inside out configuration, often destroying the canopy and the rib support structure. The wind causes flexing of the ribs and mechanical stress thereto, which may result in bending and snapping of the ribs and rib support system. The wind's destructive effect on conventional umbrellas is principally a result of the configuration of conventional umbrellas, wherein the configuration creates a higher air pressure on the underside of the umbrella's canopy as compared to the air pressure exerted on the topside of the canopy. The higher air pressure on the underside of the canopy causes the upward bend and/or lift of conventional umbrellas.
To overcome the problems associated with windy environmental conditions on umbrellas, conventional umbrellas oftentimes comprise a mechanism to release the air pressure from below the conventional umbrellas. Such mechanisms include utilizing various forms of holes, openings and vents provided in the umbrella's canopy. However, these various modifications still fail in producing a reliable umbrella having sufficient structural support to withstand high wind velocities. Also, due to the lower air pressure on the top of the umbrella as compared to the air pressure below the umbrella, under windy conditions, conventional umbrellas tend to lift and fly away.

SUMMARY OF THE INVENTION

The above-discussed and other drawbacks and deficiencies of the prior art are overcome or alleviated by an umbrella comprising an upper canopy attached to a lower canopy, wherein the lower canopy is dimensioned relative to the upper canopy to increase the positional and structural integrity of the umbrella. One manner in which the canopies can operate to achieve positional and/or structural integrity when subjected to high wind velocities is to diminish the air pressure surrounding the bottom portion of the umbrella relative to the air pressure surrounding the top portion of the umbrella.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic depicting a conventional umbrella;
FIG. 2 is a schematic depicting an exemplary umbrella of the present invention;
FIG. 3 is a schematic depicting another exemplary umbrella of the present invention;
FIG. 4 is a schematic depicting another exemplary umbrella of the present invention;
FIG. 5 is a schematic depicting another exemplary umbrella of the present invention;
FIG. 6 is a schematic depicting another exemplary umbrella of the present invention;
FIG. 7 is a schematic depicting a top view of an exemplary upper canopy; and
FIG. 8 is a schematic depicting a side view of the umbrella depicted in FIG. 7;
FIG. 9 is a schematic depicting another exemplary umbrella;
FIG. 10 is a schematic depicting a view of the topside of an exemplary upper canopy;
FIG. 11 is a schematic depicting a view of the topside of an exemplary lower canopy;
FIG. 12 is a schematic depicting a view of an underside of the upper canopy depicted in FIG. 10; and
FIG. 13 is a schematic depicting a view of an underside of the lower canopy depicted in FIG. 11.

DETAILED DESCRIPTION OF THE INVENTION

In general, disclosed herein is an umbrella capable of withstanding high wind velocities, wherein the umbrella may comprise a rain umbrella, a patio umbrella, a market umbrella, a beach umbrella, an awning, and the like. More specifically, disclosed herein is an umbrella comprising an upper canopy and a lower canopy, wherein the lower canopy serves to reduce the air pressure circulating on the underside of the lower canopy, such that the umbrella maintains both its structural integrity, i.e., the upper and lower canopies resist turning upwards, and its positional integrity, i.e., the umbrella resists “flying away” from its anchored support, when subjected to wind velocities that would otherwise disturb the positional and structural integrity of conventional umbrellas.
In conventional umbrellas, as shown in FIG. 1, a wind stream 5 hitting a leading edge 39 of the umbrella is separated such that a portion 32 of wind stream 5 moves over an edge 35 of an upper canopy 34, and another portion 36 of wind stream 5 moves over a rim 37 of upper canopy 34. Because edge 35 of canopy 34 has a greater arc than does rim 37, portion 32 of wind stream 5 has a greater distance to travel to a terminal edge 38, as compared to the distance traveled by portion 36 of wind stream 5 from the leading edge to terminal edge 38. Accordingly, portion 32 moves at a greater velocity as compared to portion 36. Because portion 32 is moving at a greater velocity than is portion 36, the air pressure over edge 35 of upper canopy 34 is lower than is the air pressure directly under rim 37 of upper canopy 34. Accordingly, as the air pressure directly under upper canopy 34 is greater than the air pressure directly above upper canopy 34, when wind stream 5 is moving at a velocity that exceeds the umbrella's capacity, the umbrella will tend to fold upward, i.e., upper canopy 34 will invert and/or the umbrella will move away from its desired position.
Furthermore, with conventional umbrellas, air pushes up under the umbrella, a force known as aerodynamic lift. The upper air stream is deflected downward. Flowing air tends to follow curving surfaces even when those surfaces bend away from the air stream. Thus, the inward bend of the upper air stream is accompanied by a substantial drop in air pressure just above the umbrella such that the umbrella is pushed upwards. These forces taken together tend to lift the umbrella against gravity.
By taking advantage of basic physical principles, the inventive umbrella disclosed herein can better maintain both its structural and positional integrity when exposed to strong wind velocities, as compared to conventional umbrellas exposed to the same wind conditions. That is, the umbrella disclosed herein is preferably formed and configured to resist structural and positional change when exposed to high wind velocities by taking the Bernoulli effect into consideration. The Bernoulli effect states that internal pressure is reduced as the stream velocity in a fluid is increased. Stream velocity increases when the distance between any two points increases. Therefore, as the distance between any two points increases, the stream velocity between those two points increases, and the internal pressure decreases.
Bearing the Bernoulli principle in mind, the umbrella disclosed herein comprises a lower canopy that extends from a rim of an upper canopy. The lower canopy is used to reduce the air pressure surrounding the bottom portion of the umbrella such that the umbrella can resist turning upwards and/or can resist positional movement during windy conditions. The degree to which the air pressure surrounding the bottom portion of the umbrella will be lessened ultimately depends on the arc length of the lower canopy in relation to the arc length of the upper canopy, wherein arc length is defined as the length along the curve of the respective canopy wherein the curve is defined by the opposite terminal edges of the respective canopy. That is, the greater the arc length of the lower canopy relative to the arc length of the upper canopy, the lower will be the air pressure surrounding the bottom portion of the umbrella, and, therefore, the less likelihood that the umbrella will turn upwards or otherwise reposition itself.
For example, referring to FIG. 2, an umbrella 1 comprises an upper canopy 2 comprising a height X, wherein height X is determined by an arc length defined by the curve formed between Points A and B, wherein Point A is located at a leading edge of an edge 21 of upper canopy 2 and Point B is located at a terminal edge of edge 21 of upper canopy 2, and wherein height X is more specifically defined by Points C and D, wherein Point C defines an apex of upper canopy 2 and Point D is a point on a rim 23 of upper canopy 2, wherein Points C and D lie on a longitudinal axis J.
Umbrella 1 further comprises a lower canopy 3, wherein lower canopy 3 comprises a height Y relative to height X, wherein height Y of lower canopy 3 is determined by an arc length defined by the curve formed between Points E and F, wherein Point E is a leading edge of an edge 33 of lower canopy 3 and Point F is a terminal edge of edge 33 of lower canopy 3.
As shown in FIG. 2, lower canopy 3 may comprise a height Y that is either less than, equal to, or greater than X, wherein height Y is more specifically defined by points G and H, where Point G defines an apex of lower canopy 3 and Point H is a point on a rim 41 of lower canopy 3, wherein Points G and H lie on longitudinal axis J. Where the height of lower canopy 3 is less than X, e.g., where the height equals about 5/6 X, lower canopy 3 is completely disposed within an underside of upper canopy 2. This embodiment is particularly advantageous as it strengthens the umbrella against the umbrella's tendency to flip inside out during high wind velocities. Where height Y of lower canopy 3 is greater than X, e.g., where height Y equals 2 X, lower canopy 3 extends downwards, away from rim 23 of upper canopy 2.
Although the height dimensions of lower canopy 3 may vary widely, in an exemplary embodiment, height Y of lower canopy 3 is about 0.84 to about 4.0 times height of X of upper canopy 2. Where height Y of lower canopy 3 is twice height X, as shown in FIG. 2, i.e., where the arc length of lower canopy 3 is equal to the arc length of upper canopy 2, umbrella 1 is balanced, such that the air pressure exerted on edge 21 is equal to the air pressure exerted on rim 33. Accordingly, when the upper and lower canopies have equal arc lengths or equal heights, less force is necessary to hold the position and structural integrity of the umbrella in place. Additionally, should even greater wind resistance be desired, then the arc length of lower canopy 3 can be extended such that the height of lower canopy 3 is substantially greater than is the height of upper canopy 2, e.g., the height of lower canopy 3 may exceed up to about 4 times the height of upper canopy 2.
The determination as to the arc length, and hence the height, of the lower canopy in relation to the upper canopy may be based on the ultimate purpose and type of umbrella. For example, referring to FIG. 3, where the umbrella comprises a rain umbrella 7, it may not be necessary to have an umbrella capable of achieving equal air pressures on both a top portion 4 and a bottom portion 6 of the umbrella as typically a user can assert a downward hand held pressure on the umbrella causing the umbrella to maintain its positional integrity. Therefore, as shown by exemplary umbrella 7 in FIG. 3, a lower canopy 8 may comprise a height Y of about 0.3 times the height X of an upper canopy 9 such that lower canopy 8 extends downwards away from bottom rim 31 of upper canopy 9 such that a portion of lower canopy 8 is visible when umbrella 7 is in an open and upright position.
Additionally, it may be desirable for height Y to be less than, equal to or slightly greater than (e.g., less than about 1.5 times) height X in umbrella 7 in order to keep the side profile of umbrella 7 sufficiently thin such that air resistance is enhanced. In an exemplary embodiment, whereby umbrella 7 can maximize side air resistance, umbrella 7 comprises a side profile 17 of about 6 inches to about 18 inches.
FIG. 4 depicts an exemplary umbrella 11, wherein umbrella 11 comprises a beach, market, or patio umbrella. Unlike umbrella 7 depicted in FIG. 3, beach, patio, and market umbrellas, such as umbrella 11, typically require anchoring supports to preserve their positional integrity. As is particularly the case for beach umbrellas, the anchoring support typically includes sand, which due to its compositional properties, provides an unsteady support. Accordingly, beach, patio, and market umbrellas are more likely to function better, i.e., maintain their positional integrity, where there is less air pressure exerted on their bottom regions as compared to the amount of pressure exerted on the bottom region of rain umbrellas. Therefore, as shown in FIG. 4, in an exemplary embodiment, umbrella 11 comprises a lower canopy 13 comprising a height Y of about 1.5 times the height X of an upper canopy 15.
Additionally, it may be desirable for height Y to be less than, equal to, or slightly greater than (e.g., less than about 1.5 times the height of X) height X in umbrella 11 in order to keep the side profile of umbrella 11 sufficiently thin such that air resistance is enhanced. In an exemplary embodiment, whereby umbrella 11 can maximize side air resistance, umbrella 11 comprises a side profile 19 of about 12 to about 30 inches.
The invention will now be described with reference to the remaining figures. However, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following or the previously detailed description or as illustrated in any of the figures. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting.
Referring to FIGS. 5 and 10-13, an exemplary umbrella 10 comprises an upper canopy 12 and a lower canopy 14. Each of upper and lower canopies 12 and 14 comprises a respective top side 60 and 62 and a respective underside 76 and 78, wherein top sides 60 and 62 define the exterior portion of umbrella 10, and undersides 76 and 78 define the interior portion of umbrella 10. Furthermore, upper canopy 12 comprises edges 80, 82, 84, and 86, wherein each of the edges extends from one point of a rim 72 to an opposite point of rim 72, and further wherein each of the edges is bisected into equal halves by an apex 68. Lower canopy 14 comprises edges 88, 90, 92, and 94, wherein each of the edges extends from one point of a rim 74 to an opposite point of rim 74, and further wherein each of the edges is bisected into equal halves by an apex 70.
Lower canopy 14 comprises an arc length, as defined by the length of any one of edges 88, 90, 92, and 94, greater than that of upper canopy 12, wherein the arc length of upper canopy 12 is defined by the length of any one of edges 88, 90, 92, and 94.
As shown in FIG. 5, an exemplary arrangement between upper canopy 12 and lower canopy 14 comprises attaching rim 74 of lower canopy to underside 76 of upper canopy 12 and attaching rim 72 of upper canopy 12 to underside 78 of lower canopy 14. In this way, upon opening umbrella 10, upper canopy 12 extends upwardly and outwardly such that its concave side would be directed over a user or a table, e.g., when in use. Preferably simultaneous to upper canopy 12's extension, lower canopy 14 also extends downwardly and outwardly such that the convex side of lower canopy 14 is directed over the user or the table, e.g., when in use.
Upper canopy 12 may be removably or permanently joined to lower canopy 14. Where the two canopies are removable from each other, attachment between the two canopies may be accomplished by any means that allows for the continuous attachment and separation of the two canopies to and from each other. Such attachment means that allow for the removable attachment of the two canopies may comprise, for example, buttons and corresponding holes, a zipper and corresponding teeth, hook and loop fasteners, and the like. Where the two canopies are permanently attached to each other, attachment between the two canopies may be accomplished by any means that allows for the permanently fixed attachment between the two canopies. Such attachment means that allow the two canopies to be permanently fixed to each other comprise, for example, stitches, glue, tape, heat sealing, and the like, and/or the two canopies may be manufactured from the same continuous piece of material.
Although umbrella 10 may be formed in a variety of ways, in an exemplary embodiment, upper canopy 12 is attached to spokes 30 of umbrella 10 in a conventional fashion. Additionally, lower canopy 14 may comprise spokes similar or identical to spokes 30. Both the upper and lower canopies may be formed of the same or different materials, wherein such materials may comprise nylon, vinyl, canvas, and the like. Additionally, lower canopy 14 may or may not comprise spokes (See FIG. 6, wherein an umbrella as described herein comprises a lower canopy attached to the umbrella, wherein the lower canopy is not attached with spokes).
Still referring to FIG. 5, lower canopy 14 further comprises an aperture 20 through which a handle 22 extends. Umbrella 10 can be opened and closed by conventional means, such as, by a push button mechanism 24.
The umbrella disclosed herein serves to withstand wind velocities that would otherwise invert the upper canopy of conventional umbrellas or that would otherwise reposition a conventional umbrella. Accordingly, the umbrella disclosed herein extends the life of the umbrella by making the umbrella resistant to high winds.
Aside from improving the wind resistant characteristics of umbrellas in general, the umbrella disclosed herein may also serve to provide a user with greater protection against the elements. That is, as shown in FIG. 5, umbrella 10 may further comprise an opening 18 formed in lower canopy 14, wherein opening 18 is configured such that a user can insert at least the crown portion of a person's head into opening 18. In this way, umbrella 10 provides a user with greater protection against the elements, such as against rain, snow, sleet, wind, and the like, as compared to conventional umbrellas.
Still referring to FIG. 5, lower canopy 14 comprises an arc distance that is greater than the arc distance of upper canopy 12. Accordingly, when a wind stream 25 hits a leading edge 16 of edge 80 of upper canopy 12, a portion 27 of wind stream 25 will be directed over top side 60 of upper canopy 12, and another portion 29 of wind stream 25 will be directed under top side 62 of lower canopy 14. Portion 29 of wind stream 25 has a higher velocity than does portion 27 of wind stream 25 due to lower canopy 14's greater arc length. The increased velocity of portion 29 results in a lower air pressure exerted on top side 62 of lower canopy 14 as compared to the air pressure exerted on top side 60 of upper canopy 12. Accordingly, the higher air pressure exerted on edge 80, e.g., of upper canopy 12 will push upper canopy 12 down against lower canopy 14 such that umbrella 10 will tend to maintain itself in the proper usable position despite the wind conditions to which umbrella 10 may be exposed.
It is to be understood herein that the umbrella described herein may comprise a lower and an upper canopy having a wide variety of shapes, wherein such shapes may include, for example, triangular, elliptical, conical, spherical, polygonal and the like. The geometrical shapes of the upper and lower canopies may be the same or different, wherein the important parameter lies in the proportion of the two canopies in relation to each other. That is, the important consideration, is that the lower canopy be structured and configured relative to the upper canopy such that the air pressure exerted on the bottom surface of the umbrella, i.e., the bottom rim of the lower canopy is lower than the air pressure exerted on the top surface of the umbrella, i.e., the top rim of the upper canopy.
It is contemplated that the umbrella disclosed herein may comprise various sizes and geometrical configurations, wherein the geometrical configuration of the upper canopy may be identical to, similar to, or different from the geometrical configuration of the lower canopy. For illustrative purposes only, variously configured umbrellas are depicted in FIGS. 6-9.
FIG. 6 depicts an umbrella 100 comprising an upper canopy 102 comprising a semicircular geometrical configuration and a lower canopy 104 comprising a square geometrical configuration. FIGS. 7 and 8 depict upper canopy 106 and a lower canopy 108 as each comprising a square shape such that the side profile of the umbrella 110 is triangular. Although FIG. 7 depicts upper canopy 106, it is contemplated that lower canopy 108 would have an identical or similar geometrical configuration and size. Additionally, FIG. 9 depicts an exemplary umbrella 40 comprising the shape of an ice cream cone for use, for example, on patio tables located at ice cream parlors. In this embodiment, umbrella 40 comprises an upper canopy 42 comprising a semi-circular shape representative of an ice cream scoop, and a lower canopy 44 comprising a conical shape representative of an ice cream cone. Here a handle 46 is inserted into an opening 48 located on a table 50.
Although for the purposes of promoting an understanding of the principles of the invention, reference has been made to the embodiments illustrated in the drawings and specific language has been used to describe the same, it will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated devices, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

Claims

1. A wind resistant umbrella comprising:

a longitudinal axis;

an upper canopy comprising:

a first rim comprising a first point; and

a first plurality of edges, wherein each edge of the first plurality extends from the first rim and meets at a first apex;

wherein the first apex and the first point lie on the longitudinal axis, and wherein a distance between the first apex and the first point is X; and

a lower canopy comprising:

a second rim comprising a second point; and

a second plurality of edges, wherein each edge of the second plurality extends from the second rim and meets at a second apex;

wherein the second apex and the second point lie on the longitudinal axis, and wherein a distance between the second apex and the second point is Y;

wherein the upper canopy is attached to the lower canopy, and wherein Y is proportioned relative to X to enhance a structural integrity of the wind resistant umbrella.

2. The wind resistant umbrella of claim 1, wherein Y is proportioned relative to X to reduce an amount of air pressure exerted on the lower canopy.

3. The wind resistant umbrella of claim 1, wherein the first rim is joined to the second canopy, and the second rim is joined to the first canopy.

4. A wind resistant umbrella comprising:

a longitudinal axis;

an upper canopy comprising:

a first rim comprising a first point; and

wherein the first apex and the first point lie on the longitudinal axis; and

a lower canopy comprising:

a second rim comprising a second point; and

wherein the second apex and the second point lie on the longitudinal axis;

wherein the first rim is joined to the second canopy, and the second rim is joined to the first canopy.

5. The wind resistant umbrella of claim 4, wherein the second apex is directed towards the first apex such that the second apex is within an underside of the first canopy.

6. The wind resistant umbrella of claim 5, wherein the wind resistant umbrella comprises at least one of a rain umbrella, a patio umbrella, a market umbrella, a beach umbrella, and an awning.

7. The wind resistant umbrella of claim 4, wherein the second apex is directed away from the first apex such that the second apex is exterior to an underside of the first canopy.

8. The wind resistant umbrella of claim 7, wherein the wind resistant umbrella comprises at least one of a rain umbrella, a patio umbrella, a market umbrella, a beach umbrella, and an awning.

9. The wind resistant umbrella of claim 4, wherein the lower canopy comprises an aperture, and wherein the wind resistant umbrella further comprises a handle, wherein the handle extends through the aperture.

10. The wind resistant umbrella of claim 9, wherein the aperture is positioned on the second apex of the lower canopy, and wherein the handle is attached to the first apex and extends through the aperture.

11. The wind resistant umbrella of claim 4, wherein the second canopy further comprises an opening sized to fit a crown of a person's head.