Title:
Vented cover for objects being transported in an airstream
Kind Code:
A1


Abstract:
A cover is provided to protect an object being transported in an air stream. The cover is configured and disposed to have at least two surfaces, a windward surface and a leeward surface. The leeward surface has at least one vent therein disposed such that a zone of negative air pressure caused by the change in the air stream causes air trapped inside the cover to be sucked out of the cover through said vent.



Inventors:
Frechette, Josee (Richmond, CA)
Stewart, Jef (Richmond, CA)
Application Number:
09/908379
Publication Date:
06/13/2002
Filing Date:
07/18/2001
Assignee:
FRECHETTE JOSEE
STEWART JEF
Primary Class:
Other Classes:
296/136.1
International Classes:
B60J11/00; (IPC1-7): B65D85/00
View Patent Images:
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Primary Examiner:
MAI, TRI M
Attorney, Agent or Firm:
Locke Lord LLP (Boston, MA, US)
Claims:

I claim:



1. A vented cover suitable for fitting over an object to be transported in an air stream, said cover comprising at least one pair of opposed, spaced-apart lateral surfaces, and one upright surface spacing apart said lateral surfaces, said upright surface being disposed such that it faces away from the direction of travel of said object being transported in said air stream, said upright surface comprising a vent therein, said vent being configured and disposed for fluid communication from the inside of the cover to the outside thereof;

2. The vented cover of claim 1 wherein said upright surface is disposed substantially at right angle to the direction of the air stream.

3. The vented cover of claim 1 wherein said vent is disposed adjacent an edge of said upright surface.

4. A vented cover suitable for fitting over an object to be transported in an air stream, said cover comprising, once fitted over said object, a first surface having a plane, said first surface comprising a first edge, said cover further comprising a second surface having a plane disposed such that it faces away from the direction of travel of said object, said second surface having a second edge, wherein at least part of said first edge is in contact with at least part of said second edge, said second surface comprising a vent therein configured and disposed so as to cause fluid communication between the inside of the cover and the outside thereof.

5. The vented cover of claim 4 wherein said vent is disposed adjacent that part of the second edge which is in contact with that part of the first edge.

6. A vented cover suitable for covering an object to be transported in an air stream, said cover comprising, when fitted over the object, a first surface having a plane facing in a direction having an angle selected from the range comprising the direction of travel to 165° from the direction of travel, said surface having a first side edge, a second surface having a plane facing in a direction having an angle greater than the angle of the first plane, said second plane having a second side edge, at least a portion of said first edge being in contact with at least a portion of said second edge, said second surface having therein a vent for fluid communication between the inside of the cover and the outside thereof.

7. The vented cover of claim 6 wherein said vent is disposed adjacent said second edge.

8. A vented cover suitable for covering an object to be transported in an air stream, said cover comprising, when fitted over the object, a first surface having a plane whose normal is disposed at an angle χ from the direction of travel of said object, said first surface comprising a first edge, said cover further comprising a second surface having a plane whose normal is disposed an angle greater than χ, said second surface having a second edge wherein at least part of said first edge is in contact with at least part of said second edge said second surface having therein a vent for fluid communication between the inside of the cover and the outside thereof.

9. The vented cover of claim 8 wherein said vent is disposed adjacent said second edge.

Description:

BACKGROUND OF THE INVENTION

[0001] The present invention relates to covers, such as hoods, sheets, wraps, coverings, tarps, and so on which may be used to protect any variety of equipment, goods, machinery which may be transported on an open-air transport. In particular, equipment to be transported on flatbed trailers, trucks, and the like are displaced through an airstream caused by the motion of the vehicle. Commonly, such equipment, goods or machinery are covered by a cover, hood, tarp, sheets or the like, and when being transported on an open-air vehicle, the flow of air moving over the equipment may cause the cover to balloon, expand outwardly and/or flutter, which may be both unsightly and dangerous. As a result, the cover may, through continuous ballooning or fluttering, eventually fly off, rip, or become displaced so that the equipment or goods being covered are no longer protected from the elements. Equipment or goods which have an irregular shape may pose particular problems of fluttering, and be more difficult to cover. Conversely, equipment which may have a streamlined or sleek shape may cause the air flowing thereover to flow faster, and in fact accentuate the ballooning and/or fluttering of the cover, which may increase the difficulty of keeping the cover on the equipment. Finally, if a cover flies off, it may cause an accident and, in any event, constitute a danger to others.

[0002] Various methods and apparatuses have been devised in order to attenuate or eliminate this fluttering and or ballooning effect. The simplest way may be to secure the cover with ropes, chains, bungee cords, nets, and other such physical restraining devices. An obvious drawback with this method comprises the additional time required to secure the cover onto the equipment, as well as the possibility of one or more of the cords breaking, moving in transit, or detaching itself such that the cover and/or parts there of may no longer be in contact with the equipment. An additional drawback comprises the fact that said method of attachment may be unsightly, and may detract from the appearance of the object being transported. When sporting equipment and/or finished articles are being transported, this may often be an important consideration.

[0003] Various attempts have been made at providing covers to fit over equipment adapted to eliminate or reduce this problem. For example, U.S. Pat. No. 5,997,071 to Mazzarelli, U.S. No. 5,673,961 to Mazzarelli and U.S. Pat. No. 4,976,389 to McLellan have attempted to overcome the above difficulty. However, none of the above prior art satisfactorily solves the problem to be addressed by the present invention. For example, the McLellan cover may reduce the buffeting associated with the specific type of object to be transported, mainly bicycles, but the type of cover has no application to devices other than bicycles and to other devices not having a narrow, knife-like profile. Mazzarelli teaches the use of a venting member, such as a plastic venting member, which may be tear-shaped and which are to be disposed over an opening in a cover. However, the Mazzarelli patents are also of limited application, and may not be used with respect to all types of covers. Further, the additional production steps necessary to add the plastic venting member of the Mazzarelli patent incur additional costs, and if the plastic cover is ever broken or ripped away for any reason, the effectiveness of the cover may be negatively affected. This drawback of the Mazzarelli patents results in the cover not having as long a useful life as may be desired.

[0004] Accordingly, it is an object of the present invention to provide a novel vented cover for objects being transported in an airstream which may be effective to cause the cover to adhere or be positioned closely to the surface of the object being transported.

[0005] It is also an object of the present invention to provide such a vented cover which may be free from whipping and buffeting during transportation.

[0006] A further object of the present invention may be to provide for a vented cover which may be easily, quickly and inexpensively manufactured.

[0007] It is an object of the present invention to provide for a vented cover which may cause air to be vented from the inside of the cover to the outside of the cover when an object is being transported in an air stream.

[0008] Still an object of the present invention may be to provide a vented cover which allows for the venting of air out from underneath the cover without the use of protruding objects, elements or venting members.

[0009] Still an object of the present invention may be to provide a vented cover which uses the natural geometry of the object to be transported thus allowing for an air pressure differential to be created between the inside and the outside of a vent disposed in the cover, such that air from inside the vent may be drawn out, i.e. sucked out of the cover thus causing a vacuum or a partial vacuum to be created inside the cover.

SUMMARY OF THE INVENTION

[0010] It has been found that by using the natural geometry, shape or form of an object to be covered by the vented hood, the venting of air from inside the cover to the outside may be enhanced. For example, an object being transported may, regardless of its shape, have a side which faces the direction of travel of the object, i.e. which looks into the wind or upwind and which will also have a face which faces backwards from the direction of travel, i.e. which looks in the same direction that the wind is travelling. Said faces may be known as the windward face and the leeward face respectively. The word “wind” is understood to mean a current of air which may be created by an object being displaced through an air stream, and does not necessarily imply that there is any movement of air relative to the ground.

[0011] A well-known principle of fluid mechanics is to the effect that when a surface along which a fluid is moving over suddenly deviates out of the path of the moving fluid, a zone of negative pressure (such as, for example, negative air pressure) may be created at the point where the surface suddenly veers away out of the path of the moving fluid. Depending on a variety of factors, such as, for example, the shape of the object, the suddenness of the change in the surface of the object, fluid velocity, etc . . . , the drop in pressure may not necessarily be great, but in any event may be enough to create a zone of negative pressure at or adjacent the point where the surface veers away. As may be understood, this zone of negative pressure may occur at the intersection of two or more surfaces, i.e. of a leeward surface (or face) and another face. However, it may not be necessary for the second, i.e downstream surface to be a leeward face, it can simply be a surface which has deviated sufficiently away from the direction of travel of the fluid to create a zone of negative pressure. The expression ‘zone of negative pressure’ is understood to mean that the pressure, i.e. the air pressure, of this zone is lower than the pressure of the adjacent or surrounding areas, such that a differential of pressure may exist between the zone of negative pressure and an adjacent or surrounding areas, and does not mean that this zone of negative pressure is a vacuum.

[0012] In accordance with a general aspect, the present invention may utilize the above described fluid mechanics principle which creates a zone of negative pressure at or adjacent the intersection of two faces or surfaces. This zone of negative pressure, i.e. negative air pressure may be advantageously used to draw air (which may be at a higher air pressure) from inside the cover, to the outside of the cover. Thus, evacuation of air from inside the cover may be effected or facilitated by providing a vent (i.e. an opening, hole, aperture, etc . . .) configured and disposed to be at or adjacent the zone of negative air pressure. Thus, if a vent, i.e. an aperture, is located on the surface of the cover adjacent or immediately in front of the zone of lower pressure, the differential in air pressure between the higher air pressure inside the cover and the lower air pressure of the zone of lower pressure outside the cover may cause air inside the cover to be drawn out, i.e. caused to flow out or be evacuated out of the cover. In this manner, air which may find its way inside of a cover covering an object being transported in an air stream may be evacuated out of the cover, and may, if the evacuation of the air is thorough enough, cause the cover to be forced down onto the surface of the object so as to adhere closely to the surface thereof. In other words, a vacuum-like effect may be created to draw air out from the inside of the cover.

[0013] In accordance with a general aspect, the vent or vents in the cover may be disposed to be at or adjacent the intersection of the surface along which the fluid, i.e. the air flows along and the surface which veers away therefrom. As may be understood, this may be so that the vent may be disposed to be (substantially) coterminous with the zone of negative pressure to the greatest degree possible. However, since the zone of negative pressure may be of indeterminate shape and size, and this shape and size may change or move in accordance with various conditions, such as the speed at which the object is being transported through the air stream, the vent need not necessarily be adjacent the intersection of the two surfaces, but may be disposed away from the intersection. In accordance with a further aspect of the present invention, a cover may be provided with a number of openings or apertures each advantageously disposed on surfaces or faces adjacent the point at which some or all of the said surfaces deviates or veers from the path of a moving fluid, such as air. In accordance with a further aspect, a cover may have a leeward surface, i.e. a surface which may be a backward facing surface, and comprise one or more vents on said surface.

[0014] The configuration of the vent may vary. It may be elongated so as to follow the intersection of the surfaces. Alternatively, it may comprise a number of separate openings shaped as needed. Further, the vent may be fitted with an overhang, or flap to prevent the entrance therein of water and so on, and which overhang may also be sized and configured to facilitate the flow of air. The opening of the vent may also be fitted with a net or mesh which way prevent insects and small animals from entering into the cover. The opening of the vent may also be fitted with a rigid or semi rigid cover, such as plastic, rubber or the like, having apertures therein to allow for the venting of air therethrough.

[0015] As may be understood, the material used in the construction of the cover may be any known material or combination of materials, and may include stiff, rigid or stretchy type of material, an in addition may be fitted to fit closely over the form of the object to be carried.

[0016] Thus, in accordance with a general aspect of the present invention, there is provided for:

[0017] a vented cover suitable for fitting over an object to be transported in an air stream, said cover comprising at least one pair of opposed, spaced-apart lateral surfaces, and one upright surface spacing apart said lateral surfaces,

[0018] said upright surface being disposed such that it faces away from the direction of travel of said object being transported in said air stream,

[0019] said upright surface comprising a vent therein, said vent being configured and disposed for fluid communication from the inside of the cover to the outside thereof;

[0020] Further, the vented cover may be configured wherein said upright surface is disposed substantially at right angle to the direction of the air stream.

[0021] Also, the vented cover may be configured wherein said vent is disposed adjacent an edge of said upright surface.

[0022] In accordance with a further aspect of the present invention, there is provided for a: a vented cover suitable for fitting over an object to be transported in an air stream, said cover comprising, once fitted over said object, a first surface having a plane, said first surface comprising a first edge,

[0023] said cover further comprising a second surface having a plane disposed such that it faces away from the direction of travel of said object, said second surface having a second edge,

[0024] wherein at least part of said first edge is in contact with at least part of said second edge,

[0025] said second surface comprising a vent therein configured and disposed so as to cause fluid communication between the inside of the cover and the outside thereof.

[0026] In accordance with a further aspect, the vented cover may be configured such that the vent may be disposed adjacent that part of the second edge which is in contact with that part of the first edge.

[0027] In accordance with yet another aspect, there may be provided for a vented cover suitable for covering an object to be transported in an air stream, said cover comprising, when fitted over the object, a first surface having a plane facing in a direction having an angle selected from the range comprising the direction of travel to 165° from the direction of travel, said surface having a first side edge,

[0028] a second surface having a plane facing in a direction having an angle greater than the angle of the first plane, said second plane having a second side edge,

[0029] at least a portion of said first edge being in contact with at least a portion of said second edge,

[0030] said second surface having therein a vent for fluid communication between the inside of the cover and the outside thereof.

[0031] In yet another aspect, there may be provided for a: vented cover suitable for covering an object to be transported in an air stream, said cover comprising, when fitted over the object, a first surface having a plane whose normal is disposed at an angle χ from the direction of travel of said object,

[0032] said first surface comprising a first edge,

[0033] said cover further comprising a second surface having a plane whose normal is disposed an angle greater than χ,

[0034] said second surface having a second edge

[0035] wherein at least part of said first edge is in contact with at least part of said second edge

[0036] said second surface having therein a vent for fluid communication between the inside of the cover and the outside thereof.

BRIEF DESCRIPTION OF THE FIGURES

[0037] FIG. 1 is a perspective view of a vented cover in accordance with the present invention which is shown fitted over an object to be transported in an air stream;

[0038] FIG. 2 is a top plan view of the vented cover of FIG. 1;

[0039] FIG. 3 is a stylized top plan view of the vented cover showing the principle of the present invention.

[0040] FIG. 4 is a stylized top plan view of an alternative embodiment if the vented cover showing the principle of the present invention.

[0041] FIG. 5 is a stylized top plan view of a further alternative embodiment of the vented cover showing the principle of the present invention.

[0042] FIG. 6 is a perspective view of a further alternative embodiment of the vented cover of the present invention.

[0043] FIG. 7 is a top plan view of the embodiment illustrated in FIG. 6.

DETAILED DESCRIPTION

[0044] In the following description and in the accompanying drawings, like elements or features bear like reference numerals.

[0045] Referring to FIGS. 1 and 2, there is shown an object 1 being transported in an air stream. Object 1 is shown to be a personal watercraft, and may be displaced on any variety of vehicles such as, for example, an open-ended trailer, flatbed truck, pick-up, etc. (not shown). Although shown to be a personal watercraft, object 1 may alternatively be any other object which may be transported on an open vehicle, such as a snowmobile, an all-terrain vehicle, a motorcycle, etc . . . The personalized watercraft 1 comprises a bottom surface 3, a front end 7 and a rear end 9. In addition, object 1 comprises opposed spaced-apart lateral surfaces 11 and 13 which surfaces 11 and 13 are spaced-apart by a number of surface, including surfaces 15, 17 and 19. The object 1 is shown to be covered snugly by a vented cover 5 which is the subject matter of the present invention.

[0046] The movement of object 1 in the direction of motion arrow 24 may cause a relative movement of air to occur in the direction of motion arrows 25, i.e. for example, from the front 7 to the rear 9 of object 1. As may be seen from FIG. 1, motion arrows 25 are shown to move over the various surfaces of the object 1, and to generally follow the shape of said surfaces. Cover 5 is shown in FIG. 1 to fit snugly over object 1, and therefore to closely follow the shape of the object 1. As may be seen, surfaces 17 and 19 comprise therein vents 31 and 33, and 35 and 37 respectively. As may be seen, surfaces 17 and 19 may best be described as surfaces which are disposed vertically or, i.e. substantially vertically, in reference to the direction of travel of object 1 being displaced, and are further disposed on the leeward side of the object 1. Further, vents 33 and 31 as well as vents 35 and 37 are disposed on surfaces 17 and 19 having each a plane which is disposed substantially, (or approximately) at 90° to the direction of travel of air as indicated by motion arrows 25.

[0047] FIG. 3 illustrates a stylized top plan view of the object 1 cover showing the venting thereof. Object 1 is shown being covered by a vented cover 5, said object 1 comprises a top (horizontal, i.e. substantially horizontal ) surface 46, and opposed, spaced-apart lateral surfaces 41 and 43, said lateral surfaces 41 and 43 being disposed substantially in a vertical plane, and surface 44 also shown to be disposed in a substantially vertical plane. Although shown to be in substantially vertical planes, it is understood that lateral surfaces 41 and 43 and surface 44 may be disposed otherwise than in a vertical plane, and for example, may comprise a curved surface which may be in part vertical and in part in a plane disposed off the vertical plane.

[0048] A well-known aerodynamic or fluid dynamic principle is to the effect that an airstream, such as airstreams 40 or 42, which moves along a surface such as surfaces 41 and 43 respectively, may, when said surfaces 41 or 43 come to an end (abruptly or otherwise), cause a zone of negative pressure to be created on the surface which veers away (surface 44) at or adjacent the intersection of surfaces 43 and 44 (or of surfaces 41 and 44). As may be understood, the zone of negative pressure may be created on the surface along which the air stream does not move along, i.e. along surface 44. Although the intersection of surfaces 41 and 44 (as well as surfaces 43 and 44) are illustrated as being substantially at 90°, it is understood that the intersection between said surfaces need not be at 90°, and may simply be at an angle sufficient to cause a deviation in the air flows, such as 40 and 42, necessary to create the zones of negative pressure 48 and 50. Thus as they move along past the end of surfaces 41 and 43, air streams 40 and 42 may cause the formation of two zones of negative air pressure, which location and size are approximately indicated by bubbles 48 and 50, at the point where said surfaces 41 and 43 abruptly come to an end (for example as they are spaced apart by surface 44) or alternatively where said surfaces 41 and 43 may be subjected to a change (sudden or otherwise) in their direction or configuration.

[0049] In order to take advantage of the zones of negative air pressure 48 and 50, cover 5 may be provided with vents 52 and 54, which vents may be configured and disposed to allow and facilitated the venting of air from inside cover 5 to the outside thereof. Thus, the location of vents 52 and 54 adjacent (i.e. for example, immediately adjacent) the end of surfaces 41 and 43 may cause air which may be located inside vent 5 to move outwardly as shown by arrows 56 and 58. As may be understood, the formation of zones of negative air pressure may occur as a result of various changes in configuration of an object being transported through an air stream, and it is understood that the location of vents 52 and 54 may be along any surface at which negative air pressure may be created, such as, for example, along surfaces by reference numbers 18 and 20 of FIG. 2.

[0050] As may be understood, the movement of an object 1 through an air stream may cause the introduction of air inside the covers, and therefore may cause said air inside the cover to be under higher pressure than the air located outside of the cover. Alternatively, the air inside the cover may be at the same pressure as the air outside the cover. In either case, the formation of zones of negative air pressure 48 and 50 outside of the cover 5, may create a pressure differential between the air pressure inside the cover 5 and the air pressure of the zones of negative air pressure 48 and 50. This air pressure differential may cause the relative higher pressured air found inside the cover to be evacuated out of the appropriately located vents 52 and 54 disposed in front, or substantially in front of the zones of negative air pressure 48 and 50. The flow of air may be created and maintained through taking advantage of the fact that fluid, such as air, will flow into a zone or relatively lower pressure from a zone of higher pressure, an in the process, vacate the zone of relatively higher pressure. Although it may be more efficient to have vents 54 and 56 disposed immediately adjacent the intersection of two surfaces such as surfaces 41 and 44, the venting of the inside of a cover 5 may nonetheless be accomplished by having the vents disposed other wise than immediately adjacent said intersection. As may be understood, any number of vents may be disposed on a surface, vertical or otherwise, in order to take advantage of this principle.

[0051] FIG. 4 illustrates a top plan view of an alternative embodiment of the present invention. As illustrated, a cover 60 is shown to be tightly covering an object being transported in an air stream in the direction of motion arrow 69. Said object comprises a front curved surface 62 which is shown to be curved and which eventually intersects with a pair of spaced-apart side surfaces 64 and 66. The intersection of front surface 62 and side surfaces 64 and 66 may cause a change which is less pronounced or less abrupt than the change of surfaces 41, 43 and 44 illustrated in FIG. 3. Nonetheless, air streams 70 and 72 which are illustrated as flowing over front surface 62 and alongside surfaces 64 and 66 may deviate at or about the intersection of said surfaces. The same aerodynamic principle as illustrated in FIGS. 1 through 3 applies to the configuration of the cover 60 illustrated in FIG. 4, namely that zones of negative pressure 76 and 78 may be created along side surfaces 64 and 66 by the interaction of air streams 70 and 72 along the shape of cover 60. Thus, the presence of vents 80 and 82 figured and disposed so as to be in front of the zones of negative pressure 76 and 78 may create a venting effect of any air which may be found inside cover 60 through said vents 80 and 82 and out of cover 60. As may be understood, alternative embodiments of the present invention may also include covers having apertures which are not disposed on leeward faces but may instead be disposed at one or more intersections of two surfaces, at which intersection a shift in the direction of an air stream may cause a zone of negative air pressure to be created.

[0052] Turning to FIG. 5, there is shown a part of a cover 80, being displaced in the direction of travel as indicated by motion arrow 82. Cover 80 is shown as having at least two surfaces, namely surface 84, and surface 86, shown to be adjacent to one another. Air flows, showing the change in direction thereof have been omitted for the sake of clarity, but a similar pattern of air movement as shown in FIG. 4 may occur over the cover of FIG. 5. Surface 84 has a plane, which plane has a normal indicated by reference number 88. As may be seen, normal 88 is disposed at an angle χ illustrated by reference number 90, taken from a reference plane 92 which is parallel to the direction of travel 82. Surface 86 also has a plane, which plane has a normal illustrated by reference number 94 disposed at an angle γ illustrated by reference number 98, taken from a reference plane 96 which is parallel to the direction of travel 82.

[0053] As may be understood, angle γ, illustrated by reference number 98 is to be greater than angle χ illustrated by reference number 90. In other word, surface 86 is to deviate from the direction of surface 84, such that angle γ is greater than angle χ. The magnitude of the increase of angle γ over angle χ0 is to be such that air flow moving over surface 84 (not shown) and which changes direction at intersection 81 may cause a zone of negative pressure illustrated by reference number 100 to be created. Although a large or sudden change, i.e. wherein angle γ is much greater than angle χ may be advisable (for example 90° greater as illustrated in FIGS. 1 to 3), it is understood that a much smaller change of for example 5° to 10° may be sufficient to effect the desired result.

[0054] FIGS. 6 and 7 illustrate an alternative embodiment of the present invention. Object 110 is shown with a cover 107, having a first surface 103 and a second surface 104 adjacent the first surface 103. As illustrated, air flow 102 is shown moving over object 110. There is illustrated a gap 105 between first surface 103 and second surface 104, which gap has a width illustrated by reference number 106. Gap 106 acts as a vent or opening, which is illustrated as being disposed from the top to the bottom of object 110. It is understood that the length of gap 105 may vary, and may greater or less than that illustrated in FIG. 6. Further, the width 106 of gap 105 may also be greater or less than that illustrated in FIG. 6. Further, as illustrated in FIG. 7, first surface 103 may have a small lip 108 which overshoots second surface 104.

[0055] As may be understood from FIGS. 6 and 7, air which may be found inside cover 107 may be caused to be evacuated out of the gap 105 through the application of the principle as described in the present application.

[0056] Although the invention has been described with reference to the prescribed embodiments, it will be understood that modifications and changes can be made without departing from the scope and spirit of the invention.