Abstract:
The present invention relates to umbrellas having various canopy shapes which shapes can be altered during use. A multiple position rib formed of a telescoping rib girder in combination with a hub slide assembly with multiple hubs allow the umbrella to be opened to two or more functional positions. An embodiment is an umbrella that can be used as a car shade having two open canopy configurations. In a first open position, all multiple position ribs are in an extended position so that the umbrella serves as a conventional rain umbrella. In a second open position, at least one of the multiple position ribs is folded to allow the umbrella to fit inside a vehicle windshield thereby serving as a sun shade. The multiple position rib can be formed of a rigid inner support assembly and a flexible outer cantilevered assembly. Flex strength properties of the outer cantilevered assembly can be varied within a rib and between ribs to provide a stable frame for certain unconventionally shaped umbrellas, including domes with flattened centers, asymmetric rib configurations, and ribs of differing lengths. Flex strength properties of the outer cantilevered assembly can be also varied to increase the flexibility of rib ends without compromising open canopy integrity. On contact rib ends can bend down toward the pole altering the shape of the canopy perimeter. The rib ends can return to their original positions when contact is terminated.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a configurable umbrella which can be converted into different shapes having a rib assembly which includes a rigid portion and a flexible portion that provides non-uniform flex strength of the ribs. 
     2. Description of the Related Art 
     A conventional umbrella typically has a cloth covered, dome shaped canopy that is symmetrical to a central pole and is supported by ribs that are secured to the pole and radiate outward. The ribs are evenly spaced around the pole and their cantilevered outer portions are equally flexed. Each rib is exactly the same and all are operated in unison via a single slide on the pole. In operation the umbrella is opened to its functional configuration or closed for storage by collapsing the ribs against the pole. 
     Conventional ribs of an umbrella have the same flex strength since each rib is formed of the same material and construction. The cantilevered portion of a conventional rib is composed of one material and is constructed with uniform thickness throughout its length. Thus, the flex strength of any rib is uniform throughout its cantilevered length. Accordingly, all conventional ribs share a common curvature profile when pressure is applied along the rib length. The curvature rate peaks in the first third of the distance from the fixed end to the free end, declines almost to zero in the middle third, and the third nearest the free end is essentially straight. 
     An open conventional canopy holds its intended shape since each rib of the umbrella is flexed in the same manner, the canopy is symmetrical to the pole, the cantilevered portions are the same length and the canopy cover is contoured to fit the flexed ribs. When these conditions are met the restraining force of the fabric and the restoring force of the flexed ribs can be sufficiently in equilibrium throughout the canopy to hold its shape. Conventional umbrellas have the shortcoming that if any of the above-described conditions are not met the ribs will not fit the fabric contour because they will seek equilibrium outside their intended positions, and the canopy will not hold its shape. 
     U.S. Pat. No. 5,505,221 describes a modification to the typical dome configuration of an umbrella with off-center support. The umbrella is symmetrical along a central vertical plane rather than the pole. Ribs of differing lengths are used to form a canopy having an elongated dome. A similarly shaped umbrella is described in Italian patent number 0372882. U.S. Pat. No. 4,838,290 describes a hat shaped umbrella with asymmetric properties, having cantilevered rib portions of differing lengths. 
     U.S. Pat. Nos. 5,307,827 and 5,355,903 issued to one of the inventors of this disclosure describe a dual function asymmetric umbrella. The primary embodiment of these patents is an umbrella in which the configuration can be altered to form a shade for auto windshield interiors. Ribs are unevenly spaced around the pole having cantilevered portions of differing lengths. The canopy has a flattened center in order to fit against a windshield and does not have a conventional dome shape. 
     In the closed position all ribs of the dual function umbrella are folded against a collapsed pole. From the closed position the umbrella can be opened and latched in either of two positions, each producing a different canopy configuration. In one open position, some of the ribs are partially extended and some are fully extended causing the canopy configuration to be approximately rectangular so it can be placed against the inner surface of a vehicle windshield as a shade. In the other open position all ribs are fully extended to produce an oval canopy to function as a conventional rain umbrella. The ribs that can be either partially or fully extended are referred to as “multiple position ribs.” Their outer portion can be extended or folded by moving two slides on the pole. The other ribs are conventionally constructed and operated. The multiple position rib inner portion supports and controls the outer flexible portion using a push bar that runs the length of a girder from the pole to a piston housed at the other end of the girder. The piston is connected to the rib by a hinge. The above-described dual function umbrella has several shortcomings such as: the multiple position rib has a limited range of motion; the multiple position rib lacks the rigidity to hold a fully extended rib firmly in place; the use of multiple position ribs and conventional ribs in the same umbrella causes canopy surface unevenness; push bars used in the multiple position rib are vulnerable to damage; when the umbrella is to be used as a car shade four ribs are fully opened to extend the canopy horizontally which makes it difficult to place against the windshield if the entire upper surface of the dashboard is not flat; and the rib construction poses a sizing problem for the car shade umbrella in that one size umbrella fits a limited number of vehicles and is either too large or too small for most windshields. 
     Conventional rib construction causes the rib tips of umbrellas to be inflexible and therefore hazardous when the canopy is being opened or is in use. It is well known that the rib tips can cause eye and other injuries. This disadvantage has always been considered inherent to umbrellas and inescapable. 
     It is desirable to provide an umbrella which can be varied in shape and provide improved stability, safety and reduced vulnerability to damage. 
     SUMMARY OF THE INVENTION 
     The present invention provides a range of umbrella shapes and configurations for increasing umbrella utility and safety. The umbrella includes rib assemblies each formed of an inner support assembly attached to an outer cantilevered assembly. The inner support assembly is rigid and the outer cantilevered assembly is flexible. The cantilevered assembly can have non-uniform flex strength. The umbrella can include a plurality of multiple position ribs and single position ribs each formed of the rib assembly extending radially from a pole. The multiple position ribs can be secured in either an extended or folded position when the umbrella is in use and the remaining single position ribs are extended. 
     The present invention provides rib assemblies with varied cantilevered rib flex strength within a rib or from rib to rib as needed to produce equilibrium between the restoring force of the ribs and the restraining force of the umbrella&#39;s canopy cover. It has been found that in asymmetrical shaped canopies the restraining force of the cover against the flexed ribs is not uniform along the length of a rib or from rib to rib. Accordingly, the flex strength of conventional ribs is not able to hold the asymmetrical shaped canopy cover in its intended shape. 
     The flex strength profile of each rib of an umbrella required for canopy equilibrium is a function of the canopy cover&#39;s stretch properties and the desired shape of the canopy. The present invention includes rib assemblies including outer cantilevered portions having flex strength profiles to achieve the following configurations: umbrellas with asymmetric domes in which flex strength profile varies between ribs; flattened or spherical dome shaped umbrellas in which the required curvature of a rib is constant or increases with distance from the fixed end; and umbrellas with soft rib tips in which flex strength is reduced at the rib ends while rib to fabric equilibrium is maintained in the rest of the canopy. 
     Flex strength properties that change along the length of a rib are achieved by changing the cross sectional characteristics along its cantilevered length, or by using multiple materials to form the cantilevered portion. More specifically, the cantilevered rib portions can be formed of a graduated or tapered cross sectional area of a rib formed of a single material; a rib formed in at least two segments with each segment having a different cross sectional area; a rib formed in segments with each segment formed of a material of different flex strength; and a rib formed in segments with at least one segment having a different cross sectional profile, such as that of a coiled or flat spring. 
     The structure of a multiple position rib allows the umbrella to be capable of at least two open positions. The multiple position rib includes a two-part telescoping girder to strongly support a hinged outer cantilevered portion of the rib. The multiple position rib is controlled by a hub slide assembly moveable on the umbrella pole. Compared to the multiple position ribs described in U.S. Pat. Nos. 5,307,827, and 5,355,903, the present invention has the advantages of reducing the number of parts, holding the ribs more firmly, allowing the ribs to be controlled through a greater range of motion, and allowing the ribs to be subjected to less damage. 
     Conventionally, the ribs of an umbrella fold toward the pole. The folded outer portion of a rib normally points toward the pole. However if only some ribs of an umbrella are partially folded while the others remain fully extended, the canopy cover will restrict and alter the direction of the folding portions which can bend the ribs. In the present invention, the outer portion of the multiple position rib is hinged to a swiveling pivot joint to allow the rib to be partially folded while others remain fully extended. 
     The present invention allows the umbrella to be latched temporarily while partially open. This permits the operator to position the umbrella on a dashboard so that the single position ribs are free to open fully against the windshield. A latched partially open position also affords a person leaving a vehicle more immediate rain protection than otherwise possible. 
     The rib construction of the present invention also provides increased rib tip flexibility without compromising overall stability. Flexible rib ends have the advantages of the ability to compress temporarily part of the umbrella&#39;s perimeter surface area, thereby an umbrella can be opened in doorways too narrow for conventional umbrellas, the ability for allowing the user to avoid opening the umbrella in the rain; the ability of its flexible rib ends to bend on contact with the door&#39;s frame and remain clear of the door path, since if they do not encounter the door&#39;s frame they will assume their intended shape in the windshield; and the ability to flex when contacting a person or object which is especially beneficial in confined or crowded areas such as busy sidewalks for improved safety. Accordingly, the umbrella construction makes it possible for one size to fit most windshields. In addition, the umbrella has the advantage that persons seated next to one another in an open stadium can fold a portion of the umbrellas to allow the umbrellas to be used without intruding on each other. 
     Umbrellas are widely used as promotional items. Corporations and other organizations purchase umbrellas with their name or logo imprinted on the canopy cover and redistribute them as a means of advertising. The present invention enhances the promotional value of umbrellas because flattened canopy surface areas provide a larger viewable area for logos and other promotional art than conventionally domed surfaces. This is especially true for using the umbrella as a car shade because its flattened surface is readily and fully viewable not only when it is in use as a rain umbrella but also when it is used as a car shade. 
     These and other features of the invention can be further understood with reference to the following drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross sectional view of the umbrella of the present invention which can be used as a vehicle shade showing a cut away pole and hub slide assembly with one multiple position rib without a canopy cover. The umbrella is open and the rib is extended in an open position. 
     FIG. 2 is an exploded side view of a swivel joint and assembly shown in FIG.  1 . 
     FIG. 3A is a perspective view of the hub slide assembly shown in FIG. 1, the upper and lower sections of split hub are adjacent to one another. 
     FIG. 3B is a perspective view of a the hub slide assembly shown in FIG. 1, the upper and lower sections of the split hub are separated. 
     FIG. 3C is a perspective view of the hub slide assembly shown in FIG.  1 . 
     FIG. 4 is a cut away view of two hub slide leaf latches of the split hub slide when the umbrella is in a first open position. 
     FIG. 5 is a cross-sectional view of the umbrella when the umbrella is in a second open position wherein a multiple position rib is in a folded position. 
     FIG. 6 is a cross-sectional view of the umbrella shown in FIG. 1 when the umbrella is in a closed position. 
     FIG. 7A is a top plan view of a canopy used with FIG. 1 with all ribs extended in the first open position. 
     FIG. 7B is a side elevational view of the canopy shown in FIG.  7 A. 
     FIG. 8A is a top plan view of a canopy used with FIG. 1 in a second open position, the umbrella is open with four single position ribs extended and four multiple position ribs folded. 
     FIG. 8B is a side elevational view of the canopy shown in FIG.  8 A. 
     FIG. 9 is a side view of an alternate embodiment of this invention having a flattened dome and flexible skirt. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     During the course of this description like numbers will be used to identify like elements according to the different figures which illustrate the invention. 
     FIGS. 1-8 illustrate an umbrella having a flattened canopy surface with two open positions and a closed position which can be used as a modified car shade in accordance with the teachings of the present invention. The umbrella includes at least one multiple position rib and at least one single position rib. Alternately, the umbrella can be formed of all multiple position ribs. FIGS. 7A-7B show a top and side view of a first open position in which all multiple position ribs are extended. The umbrella in this position takes the form of a conventional umbrella. FIGS. 8A-8B show a top and side view of a second open position in which the single position ribs are fully extended and the multiple position ribs are partially extended. In the second open position, the single position ribs extend laterally and the multiple position ribs extend vertically. The umbrella in this form takes the form of a shade screen. The canopy can have a desired canopy shape such as a quadrilateral, rectangle or trapezoid so that the shade screen can fit readily against the inner surface of a vehicle windshield. In the closed position all ribs are folded against a pole of the umbrella. 
     FIG. 1 illustrates umbrella  10  comprising pole  11  and multiple position rib assembly  12 . Multiple position rib assembly  12  comprises inner support assembly  14  and outer cantilevered assembly  16 . Inner support assembly  14  has a rigid structure and outer cantilevered assembly  16  has a flexible structure. Inner support assembly  14  comprises girder rod  18 , girder sleeve  20 , control strut  22 , link hinge  24 , beam  26 , link rod  28  and swivel pivot joint  30 . Girder sleeve  20  is moveable to be telescoping with girder rod  18 . Girder sleeve  20  is slotted to receive link hinge  24 . Girder sleeve  20  is connected to control strut  22  with pivot  17 . 
     Link hinge  24  connects girder rod  18  to beam  26 . End  21  of link hinge  24  is pivotally connected to girder rod  18 . End  25  of beam  26  is pivotally connected to end  23  of link hinge  24 . End  25  of beam  26  is also pivotally connected to link rod  28 . 
     Outer cantilevered assembly  16  comprises inner rib section  34 , outer rib section  36 , rib hinge  38  and end cap  39 . End  33  of inner rib section  34  is attached to rib hinge  38 . End  35  of inner rib section  34  is attached to outer rib section  36 . Preferably, outer rib section  36  is formed of a coil spring. Upon contact with an object (not shown), outer rib section  36  bends towards pole  11 , thereby altering the shape of outer cantilevered assembly  16  and a canopy (not shown) attached thereto. After contact is terminated, outer rib section  36  returns to its original position. Inner rib section  34  can be formed of a larger cross section area than outer rib section  36  for changing the flex strength along the length of outer cantilevered assembly  16 . Alternately, the inner rib section  34  and cantilevered section  36  can be integral formed as a single tapered rib. 
     End cap  39  fits over end  37  of outer rib section  36 . End cap  39  can be formed of a resilient material. 
     Rib hinge  38  is pivotally attached to link rod  28  as shown in FIG.  2 . Rib hinge  38  is also pivotally attached with swivel pivot joint  30  to girder sleeve  20 . Swivel pivot joint  30  swivels rib hinge  38  and girder sleeve  20 . 
     Beam  26  is perpendicular to pole  11  when umbrella  10  is in the first open position, as shown in FIG.  1 . Since FIG. 1 excludes a canopy cover, inner support assembly  14  and outer cantilevered assembly  16  form a straight line perpendicular to pole  11  as it would prior to attaching the canopy cover. In this first open position, rib hinge  38  rests on girder sleeve  20  for rigidity to help prevent canopy inversion in high wind conditions. 
     Broken line  32  shown in FIG. 1 illustrates a curvature profile of outer cantilevered assembly  16  when attached to a fabric canopy cover (not shown). The rate of curvature of broken line  32  increases with distance from the secured end of outer cantilevered assembly  16  which comprises inner rib section  34  attached to rib hinge  38 . Preferably, inner rib section  34  is tapered to have a smaller width as the distance increases from rib hinge  38  for providing flex strength that decreases with distance from rib hinge  38  in order to achieve equilibrium with the restraining force of the canopy fabric. The flex strength profile of each rib of an umbrella required for canopy equilibrium is a function of the canopy cover&#39;s stretch properties and the desired shape of the canopy. 
     In an alternate embodiment, inner rib section  34  is formed of a different material than the material used for outer rib section  36 . Preferably, inner rib section  34  is formed of a material having greater flex strength than the material of the outer rib section  36 . For example, inner rib section  34  can be formed of a nylon material filled with glass fibers or other stiffening fillers and outer rib section  36  can be formed of unfilled nylon. 
     Inner support assembly  14  is coupled to fixed hub  40  and hub slide assembly  42 . End  27  of beam  26  is pivotally connected to pole  11  by fixed hub  40 . As illustrated in FIGS. 3A-3C, hub slide assembly  42  is comprised of base hub  43 , base hub shaft  44 , split hub  46 , base hub toggle lock  48 , hub separator spring  50 , sleeve  52 , and two split hub leaf latch assemblies  54 ,  56 . Hub slide assembly  42  slides along the pole  11 . Split hub  46  slides along base hub shaft  44 . End  19  of girder rod  18  is pivotally connected to base hub  43 . Split hub  46  is comprised of upper section  45  and lower section  47 . Lower section  47  of split hub  46  is pivotally attached to end  31  of control strut  22  of multiple position rib assembly  12 . Sleeve  52  preferably is formed of a steel lining and provides for hub slide assembly  42  to interface with pole  11 . 
     Base hub toggle lock  48  secures hub slide assembly  42  at any position along pole  11  when base hub toggle lock  48  is extended horizontally. Movement of base hub toggle lock  48  upward or downward from the horizontal against base hub shaft  44  disengages hub slide assembly  42  to allow movement of hub slide assembly  42 . Hub separator spring  50  is positioned between upper section  45  of split hub  46  and base hub  43 . Hub separator spring  50  accelerates the downward movement of upper section  45  when upper section  45  is unlatched. Hub separator spring  50  compresses when upper section  45  is latched. 
     The position of lower section  47  of split hub  46  on base hub shaft  44  determines whether the umbrella  10  opens to either the first open position shown in FIG. 1 or the second open position shown in FIG.  5 . In the first open position, lower section  47  of split hub  46  is secured adjacent to upper section  45  of split hub  46 , as shown in FIG.  3 A. In the second open position, lower section  47  of split hub  46  is separated from upper section  45  of split hub  46 , as shown in FIG.  3 B. When lower section  47  is secured at the top of base hub shaft  44  with leaf latch  54  while the umbrella is opening umbrella  10  is placed in the first open position in which multiple position rib assemblies  12  are fully extended. When lower section  47  is not secured at the top of base hub shaft  44 , umbrella  10  is placed in the second position with multiple position rib assemblies  12  in a folded position when the umbrella  10  is opened. 
     Split hub leaf latch assemblies  54  and  56  are used respectively to latch and unlatch lower section  47  of split hub  46  and upper section  45  of split hub  46 . Referring to FIG. 4, each split hub leaf latch assembly  54 ,  56  comprises leaf spring  60 , plunger  62 , plunger spring  64 , and latch spring  66 . Leaf spring  60  is received in cavity  67  in the slide portion  44  of base hub  43 . 
     Hub leaf latch assemblies  54  and  56  automatically release respectively lower section  47  and upper section  45  of split hub  46  when the base hub shaft  44  moves from upper section  70  to lower section  72  of pole  11 . Upper section  70  of pole  11  has a larger diameter D 1  than the diameter of lower section D 2 . When plunger  62  passes from the larger diameter D 1  of upper section  70  of pole  11  to the smaller diameter D 2  of lower section  72  of pole  11 , plunger  62  is pushed against lower section  72  by plunger spring  64 . Movement of plunger  62  depresses leaf spring  60  and allows split hub  46  to pass over it because plunger spring  64  overrides lighter latch spring  66 . Latch spring  66  maintains outward pressure on the leaf spring  60 . Hub leaf latch assemblies  54  and  56  can also be manually operated to release lower section  47  and upper section  45  of split hub  46  by depressing leaf spring  60 . 
     FIG. 5 illustrates multiple position rib assembly  12  of umbrella  10  in the second open position. Lower section  47  of split hub  46  is separated from upper section  45  of split hub  46 . Control strut  22  extends vertically. Outer cantilevered assembly  16  is folded towards pole  11 . 
     FIG. 6 illustrates multiple position rib assembly  12  of umbrella  10  in the closed position. Lower section  72  of pole  11  is telescoped within upper section  70  of pole  11 . In this closed position, inner support assembly  14  and outer cantilevered assembly  16  collapse to fold against pole  11 . Beam  26  is folded against upper section  72 , link rod  28  is pivoted against beam  26 . A portion of girder rod  18  and girder sleeve  20  also rest against beam  26 . Inner support assembly  14  rests against girder sleeve  20  and the control strut  22 . Button lever and pole extension release mechanism  80  locks umbrella  10  in the closed position. Hub slide assembly  42  is received in cavity  82  of handle  84 . 
     In operation, upward movement of the base hub  43  on pole  11  opens umbrella  10  into the first open position shown in FIG.  1 . Downward movement of the base hub  43  on pole  11  closes umbrella  10  into the closed position shown in FIG.  6 . Umbrella  10  is closed from either the first open position or the second open position by pulling split hub upper section  45  to its lowest position on base hub shaft  44  which causes base hub toggle lock  48  to unlock hub slide assembly  42 . Continuation of the downward pulling motion moves base hub  43  over pole extension latch  58  to collapse lower section  72  of pole  11  inside upper section  70  of pole  11 . 
     To open umbrella  10  to rain position shown in FIG. 1, the user depresses button lever and pole extension release mechanism  80  and pushes upward on lower section  47  of split hub  46 . The upward motion raises both upper section  45  and lower section  47  of split hub  46  to their highest position on the base hub shaft  44  to be engaged by leaf latch assemblies  54 ,  56 . The upward motion also places hub slide assembly  42  at the top of upper section  72  of pole  11 . Hub slide assembly  42  can be secured in place by raising base hub toggle lock  48 . Opening umbrella  10  to the second open position is achieved in a similar manner except that the user pushes upward on upper section  45  of split hub  46 . Lower section  47  of split hub  46  remains near the bottom the base hub shaft  44  when upper section  45  is secured by leaf latch  56 . 
     In one embodiment, the flex strength of outer cantilevered assembly  16  of at least one multiple position rib assembly can be different than the flex strength of the outer cantilevered assembly  16  of any of the other rib assemblies. 
     FIGS. 7A and 7B illustrate umbrella  10  having multiple position rib assemblies  12  and single position rib assemblies  90  extended horizontally. Canopy cover  92  is in the first open position. Preferably, umbrella  10  includes four multiple position rib assemblies  12  and four single position rib assemblies  90 . Single position rib assemblies  90  are identical in construction to the multiple position rib assembly  12  except that pivot joint  30  does not swivel. Canopy  92  can be attached to multiple position rib assemblies  12  and single position rib assemblies  90  with canopy tie down straps  94 . Girder rods  18  of all eight preferred multi-position rib assemblies and single position rib assemblies can be attached pivotally to the base hub  43 . Upper section  45  of split hub  46  can be pivotally attached to control struts  22  of each of the four preferred single position is rib assemblies  90 . Lower section  47  of split hub  46  can be pivotally attached to control struts of each of the multiple position rib assemblies  12 . 
     Horizontal panel  96  of canopy cover  92  extends between each pair of single position rib assemblies  90 . Vertical panel  97  of canopy cover  92  extends between each pair of multi-position rib assemblies  12 . Corner panel  98  of canopy  92  extends between an adjacent single position rib assembly  90  and a multi-position rib assembly  12 . Center mount screw cap  99  secures canopy  92  to pole  11 . 
     FIGS. 8A and 8B illustrate umbrella  10  including canopy cover  92  in the second open position. Single position ribs  90  extend horizontally and the multiple position rib assemblies  12  are vertical. 
     When the umbrella  10  is in the second open position the outer cantilevered assembly  16  of four single position rib assemblies  90  have less curvature than in the first open position. When the multiple position rib assemblies are folded in the second open position the perimeter of canopy cover  92  is smaller than it is in the first open position, relaxing canopy  92  pressure on the four single position rib assemblies  90  causing them to flatten. Because outer rib section  36  is a flexible spring that will bend on contact with a car door&#39;s frame, umbrella  10  can fit windshields several inches narrower than the width of umbrella  10 . 
     FIG. 9 illustrates a soft-skirted rain umbrella. This embodiment is conventional in purpose and operation. Rib placement and symmetry are also conventional. However, conventional rib design and construction are improved by this embodiment to soften the rib ends of the umbrella. As illustrated by FIG. 9 outer dome  102  is flattened and rib curvature rate accelerates at outer cantilevered portion  104  of ribs  106 . Outer cantilevered portion  104  comprises inner section  107 , outer section  108  and end cap  110 . Inner section  107  is conventionally constructed with a uniform cross sectional profile. Outer section  108  is formed of a flexible coil spring with sufficient strength to maintain canopy  112  intended shape in use. End cap  110  can be formed of a resilient material. 
     It is to be understood that the above-described embodiments are illustrative of only a few of the many possible specific embodiments which can represent applications of the principles of the invention. Numerous and varied other arrangements can be readily devised in accordance with these principles by those skilled in the art without departing from the spirit and scope of the invention.