Flip flops with wind and water barrier
Flip flops with a barrier circumscribing the flip flop sole. The barrier protects the feet from water splashes, puddles, wet grass and wind. The flip flops are open in a vertical direction, and therefore highly breathable. The barrier is waterproof and therefore provides excellent water protection. The barrier can be about 0.5-4 inches or about 0.7-3 inches tall. Alternatively, the barrier height can be at least 1/3, 40%, 1/2, 2/3, or 3/4 the length of a toe strap. The barrier can be made of closed cell foam or plastic film. The barrier can have attachment tabs for attachment to the sole. The attachment between the sole and barrier is water tight.
The present invention relates generally to sandals and in particular to thong/flip flop sandals that protect the feet from water splashes, puddles, wet grass, and wind.
BACKGROUND OF THE INVENTIONFlip flop or thong sandals are popular for their breathability and comfort. However, the openness causes some problems. Conventional flip flops do not protect the feet from water splashes, puddles or wet grass. Also, flip flops provide no protection from wind, which can be a problem in cool weather.
A number of patents teach sandals with toe guards. For example, U.S. Pat. No. 6,493,965, 6,990,753, and 7,234,251 teach toe guards that protect the toes from rocks and injury. These sandals provide very limited protection from water splashes, wet grass or wind. Also, they provide essentially zero protection from water in case a user steps into a water puddle.
U.S. Pat. No. 2,491,297 teaches footwear with a thong. It can provide protection from water, but lacks the breathability and comfort of a sandal or flip flop.
U.S. Pat. No. 2,327,322 teaches a shoe construction with a “vamp frame” that “grips the foot of the wearer firmly”. Since the vamp frame grips the foot, the shoe does not provide the breathability and comfort of flip flops.
U.S. Pat. No. 5,893,221 teaches a sandal having a heel cup that stabilizes the ankle by reducing inversion and eversion of the heel. The heel cup impairs the breathability desired of flip flop sandals. The heel cup edges do not provide useful protection from wind and water.
US Patent D453,611 shows a design for a flip flop sandal with a short ridge surrounding the flip flop. The ridge does not provide substantive protection from wind and water. Also, in the heel area, the ridge comprises a heel cup that reduces breathability. The heel cup conforms to the shape of the heel, which is undesirable for breathability and comfort.
The combination of high breathability and water protection is desirable for footwear. Both are long-felt needs. However, these needs are generally in conflict and force undesirable design tradeoffs.
There is a need for comfortable flip flop sandals that provide breathability in combination with wind and water protection.
SUMMARYProvided is a flip flop sandal having a sole, a medial foot strap and a lateral foot strap. The medial foot strap extends over the medial side of the foot, and the lateral foot strap extends over the lateral side of the foot. The foot straps are connected to the sole, and to a connection point. A toe strap is connected between the connection point and the sole. The toe strap is located such that it extends between the big toe and second toe of a wearers foot. Also present is a barrier disposed around the sole and attached to the sole. The barrier extends upwards and has a minimum height everywhere of at least 40% or ½ a toe strap length.
Accordingly, the barrier provides wind and water protection for the foot.
The barrier can also have a height of about 0.5 to 4 inches, or ½ a toe strap length to 6 inches.
The sole may comprise a gap area on the sole. The gap area is a portion of the sole where the foot does not contact. The gap area can be in the heel portion. The gap area is disposed adjacent to the barrier.
The barrier does not grip or compress the foot. In other words, the barrier does not hold the flip flop onto the foot when the foot is lifted vertically. Only the straps hold the flip flop on the foot.
The barrier can comprise an attachment tab for attachment to the sole. The attachment tab can be disposed inside the sole, i.e. in between upper and lower layers of the sole. The upper and lower sole layers can be laminated and attached by adhesive, as known in the art.
The medial and lateral foot straps can be attached to an inner surface of the barrier. This can help to hold up the barrier, so that it does not fall over.
The present flip flop can comprise a removably attachable cover, removably attachable to the foot straps. Hook and loop fastener can be used for attachment.
The barrier and cover can be made of closed cell foam for example. The barrier and cover can be impermeable to water and wind.
The present invention provides flip flop sandals having a barrier circumscribing the sandal. The barrier is tall enough to provide useful protection from water splashes, puddles, wet grass and wind. For example, the barrier can be about 0.5-4 or 0.7-2.5 inches tall (measured from a top surface of the sandal sole). The barrier is preferably impermeable to water and wind. For example, the barrier can be made of closed-cell foam or rubber or foam rubber. The barrier does not grip or compress the foot (i.e. does not grip two opposite sides of the foot at the same time), and therefore does not hold the sandal onto the foot when the foot is lifted vertically. The barrier can be spaced away from a wearers foot so that it does not impair breathability.
The present invention provides the desirable combination of excellent breathability and excellent water protection. Breathability is provided because the flip flops are open in the vertical direction and the barrier is wide enough to allow air circulation around the sides of the foot. Water protection is provided because the barrier is impermeable to water and is tall enough to block splashes, wet grass, and puddles.
The medial foot strap 24 covers the medial side of the foot, and the lateral foot strap 26 covers the lateral side of the foot, as known in the art.
According to the present invention, a barrier 30 is disposed around the perimeter of the sole 20. The barrier 30 and sole 20 are attached at a seam 32, which may have a waterproof construction. For example, the barrier 30 and sole 20 may be attached at the seam 32 by rubber cement, contact cement or other waterproof adhesive.
The barrier 30 has an interior surface 31 and an exterior surface 33.
The barrier 30 may comprise a vertical seam 34 in embodiments where the barrier is made from a strip of material wrapped around the sole 20. The vertical seam 34 will not be present in some embodiments of the invention. For example, if the sole 20 and barrier 30 comprise a single integral part (e.g. made by molding), then the vertical seam 34 and seam 32 will not be present.
The flip flop sandal can be made of many materials known in the art. For example, the sole 20 can be made of ethylene vinyl acetate (EVA) foam, polyurethane foams, rubber or foam rubbers. The straps 22 24 26 can be made of nylon or polyester fabric or webbing, leather, plastic or rubber. The use of such materials in sandals and flip flops is known in the art.
The straps 22 24 26 can be attached to the sole 20 with adhesive such as contact cement or rubber cement. For example, the sole 20 can have a layered structure and the straps 22 24 26 can extend between the layers comprising the sole 20. Such structures and construction methods are known in the art of sandal and flip flop fabrication.
The barrier 30 is made of semi-rigid or flexible material able to hold itself vertically without falling over. Also, the barrier 30 is able to flex as a wearer walks. The barrier 30 can be made of many materials known in the art: EVA foam, polyurethane foams, solid rubber or foam rubber, polyvinyl chloride (PVC) film or foam, fabrics or polymer-impregnanted fabrics, and polyester or polyethylene foams or film. The barrier 30 can also be made of solid film or sheet, such as PVC or rubber film or sheet or leather. The barrier 30 can be opaque or transparent. Preferably, the barrier 30 is made of water-impermeable material, such as closed cell foam or solid polymeric films. The present invention is not limited to any particular material for the barrier 30.
In some embodiments, polymeric closed-cell foams may be preferred for the barrier 30 because they are lightweight, flexible, waterproof and resist falling over.
Also the barrier 30 may comprise a laminated material, with the laminated layers oriented vertically (not shown). For example, the barrier 30 may comprise a layer of EVA foam and a layer of decorative fabric. The decorative fabric (not shown) can cover the interior and/or exterior surfaces of the barrier 30. The fabric may protect the foam from abrasion and damage.
The barrier can have a minimum height for all locations along the length of the barrier 30 (i.e. “everywhere”). Alternatively, the barrier 30 can have an average height, averaged over the entire length of the barrier 30.
The toe strap 22 has a length 40. The toe strap length 40 is measured between the sole top surface 38 and the connection point 28. It is noted that the toe strap length 40 refers to the length of the toe strap 22 when straightened. If the toe strap 22 has a built-in curvature, it should be straightened to determine the toe strap length 40.
If the sole 20 has a raised area where the toe strap 22 is attached to the sole 20 (not shown here, but a raised area at the toe strap-sole attachment is present in D453,611 to Birkenstock), then the toe strap length is defined as including the height of the raised area. In other words, the toe strap length for the purposes of the present claims will be the measured toe strap length plus the height of the raised area. The ridge circumscribing the sole of D453,611 is about 31% of the toe strap length.
Typically, flip flop sandals for adults have a toe strap length 40 of about 1-2 inches. A toe strap length 40 of 1.5 inches is common. In some embodiments of the invention, the barrier height 36 is at least ⅓, 40%, ½, ⅔, or ¾of the toe strap length everywhere along the length of the barrier.
Alternatively, the barrier height 36 can be at least 0.5-0.7 inches or at least ⅓ the toe strap length 40, whichever is greater. This alternative requirement will tend to accommodate variations in flip flop sizes and toe strap lengths while assuring adequate barrier height even for small size flip flop sandals.
The barrier 30 has a thickness 42. The thickness 42 can be about 0.04-0.75 inches or 0.125-0.5 inches for example. The optimal barrier thickness will depend on the weight, rigidity and density of the barrier material. Lightweight and low density barrier materials can have greater barrier thickness.
One specific embodiment has a barrier 30 made of EVA closed-cell foam with density 2 pounds/cubic foot, a thickness 42 of 0.25 inches and a height 36 of about 1-1.5 inches or about 0.8-1.2 times the toe strap length (height varies with location in this specific embodiment).
The barrier 30 may also be made of solid plastic film or sheet, such as PVC or rubber film. In such embodiments, the barrier can be thinner than 0.05 inches. The barrier 30 should be thick enough and rigid enough such that it can stand vertically without falling over.
The present flip flop sandals are worn and used like conventional flip flops. The wearers foot is disposed between the sole 20 and the straps 22 24 26. The toe strap 22 is disposed between the big toe and the second toe, as known in the art. While walking, the flip flop moves vertically (i.e. “flip flop action”) relative to the foot, like conventional flip flops. The barrier 30 does not interfere with the flip flop action movement of the flip flop.
The barrier 30 does not hold the flip flop on the foot and does not grip or compress the foot. In other words, the barrier 30 does not compress two opposite sides of the foot simultaneously. Consequently, the barrier 30 does not interfere with vertical movement required for flip flop action.
Also consequently, the present flip flop is quickly and easily put on the foot, and easily removed. The flip flop can be put on and taken off without using the hands, and can be just as easy to take on and off as a conventional flip flop sandal.
Only the straps 22 24 26 hold the flip flop on the foot. Without the straps 22 24 26, the flip flop will not remain on the foot when the foot is lifted, because the barrier 30 does not grip the foot.
However, it is noted that the barrier 30 may prevent horizontal movement of the flip flop relative to the foot. This may occur if the foot slides across the sole 20 for example. The barrier may in this case prevent the foot from sliding off the sole 20. However, this function is generally not encountered with normal use, but rather may occur with a misstep or fall. Such incidental interference with horizontal movement is distinct from holding the flip flop on the foot. The barrier 30 does not hold the flip flop onto the foot when the foot is lifted vertically.
It is noted that since the barrier 30 is typically made of soft and flexible closed cell foam, the barrier may not be able to prevent the foot from sliding off the sole 20 in some embodiments and some situations.
In the embodiment of
The embodiment of
Also shown in
The upper sole 20A is shown with an optional notch 54. The notch 54 accommodates the attachment tab 52. The notch 54 may alternatively be present in the lower sole 50. The notch 54 is optional in the present invention.
The attachment tab 52 may create bumps in the foot bed area 44, or voids between the upper sole 20A and lower sole 50, particularly if the notch 54 is not present. There are several ways to avoid this potential problem. For example, the attachment tabs 52 can be made thin enough to not create bumps, or the attachment tabs can be made of soft or compressible material.
Alternatively, as shown in
Alternatively, as shown in
These design options can prevent the attachment tabs 52 from creating undesirable bumps.
The wall portion 56 can be made of closed cell foam and the attachment tab layer 58 can be made of woven or knitted fabric or polymeric film for example. The fabric can be impregnated with polymeric material, such as polyurethane, PVC or rubber for example. An advantage of using fabric for the attachment tabs 52 is that it can be thin, and consequently it will not create bumps in the sole top surface 38.
In the embodiment of
An advantage of attaching the straps 24 26 to the barrier 30 is that it helps to hold the barrier 30 upright. If the barrier 30 is free-standing (i.e. is not attached to the straps 24 26), then it can tend to fall over after extended use.
The cover 80 may rest against a top edge 85 of the barrier 30 and thereby provide enhanced protection against wind, water splashes and rain. The cover 80 may or may not be removably attachable to the top edge 85.
The hook/loop fastener 82 84 can be replaced with other types of removable attachments, such as buttons, magnets or the like.
An advantage of the cover 80 is that it increases the insulating ability of the flip flop. Optionally, the cover can be larger than the flip flop so that it slightly overhangs the barrier 30.
If the notches 92 are covered with a water resistant or waterproof material, then the notches 92 do not create a lowering of the barrier height as its defined in the present claims.
The holes 90 and notches 92 can be covered with breathable fabric or mesh and thereby provide increased breathability and lighter weight without significantly affecting water protection.
The holes 90 or notches 92 can provide points for attaching decorative accessories. Also, the holes 90 or notches 92 can comprise transparent windows.
The present invention provides a desirable combination of exceptional breathability with excellent water protection. The present flip flop is highly breathable because the top is mostly open, and because it can move vertically relative to the foot. The breathability is superior to enclosed shoes made with breathable fabrics. The barrier provides exceptional water protection because it can be made of water impermeable, non-breathable material such as closed cell foam. If the barrier is tall enough, it can provide better water protection than a water resistant shoe.
Claims
1. A flip flop sandal, comprising:
- 1) a sole comprising a foot bed area;
- 2) a medial foot strap attached to the sole and to a connection point;
- 3) a lateral foot strap attached to the sole and to the connection point;
- 4) a toe strap, connected to the sole and to the connection point, wherein the toe strap is located such that it extends between the big toe and the second toe of a wearers foot;
- 5) a barrier disposed around and attached to the sole, wherein the barrier extends upwardly, forms a continuous loop around the foot bed, and has a height everywhere of at least 40% of a toe strap length
2. The flip flop sandal of claim 1 wherein the barrier height is in the range of 0.5 to 5 inches everywhere.
3. The flip flop sandal of claim 1 wherein the barrier height is in the range of ½ a toe strap length to 6 inches everywhere.
4. The flip flop sandal of claim 1 wherein the barrier height is everywhere in the range of 0.5 inches or ½ a toe strap length, whichever is greater, to 5 inches.
5. The flip flop sandal of claim 1 wherein the barrier and the sole comprise a single integral part.
6. The flip flop sandal of claim 1 wherein the barrier has a height everywhere of at least ⅔ the toe strap length to 4 inches.
7. The flip flop sandal of claim 1 wherein the sole comprises an upper sole and a lower sole, and the barrier comprises an attachment tab disposed between the upper sole and the lower sole.
8. The flip flop sandal of claim 1 wherein an outside surface of at least one of the foot straps is attached to an interior surface of the barrier.
9. The flip flop sandal of claim 1 further comprising a cover, wherein the cover is removably attachable to at least one of the foot straps.
10. A flip flop sandal, comprising:
- 1) a sole comprising a foot bed area;
- 2) a medial foot strap attached to the sole and to a connection point;
- 3) a lateral foot strap attached to the sole and to the connection point;
- 4) a toe strap, connected to the sole and to the connection point, wherein the toe strap is located such that it extends between the big toe and the second toe of a wearers foot;
- 5) a barrier attached to the sole, wherein the barrier extends upwardly, forms a continuous loop around the wearers foot, and has a height in the range of ½ of a toe strap length to 6 inches in a front portion, has a height of 1/3 the toe strap length to 4 inches in a rear portion.
11. The flip flop sandal of claim 10 wherein the barrier is, on average, taller in the front portion than in the rear portion.
12. The flip flop sandal of claim 10 wherein the barrier has a height in the range of ⅔ the toe strap length to 2.5 inches everywhere.
13. The flip flop sandal of claim 10 wherein the sole comprises an upper sole and a lower sole, and the barrier comprises an attachment tab disposed between the upper sole and the lower sole.
14. The flip flop sandal of claim 10 wherein an outside surface of at least one of the foot straps is attached to an interior surface of the barrier.
15. The flip flop sandal of claim 10 further comprising a cover, wherein the cover is removably attachable to at least one of the foot straps.
16. The flip flop sandal of claim 10 wherein the barrier and the sole comprise a single integral part.
17. A flip flop sandal, comprising:
- 1) a sole comprising a gap area in a heel portion, and a foot bed area;
- 2) a medial foot strap attached to the sole and to a connection point;
- 3) a lateral foot strap attached to the sole and to the connection point;
- 4) a toe strap, connected to the sole and to the connection point, wherein the toe strap is located such that it extends between the big toe and the second toe of a wearers foot;
- 5) a barrier disposed around and attached to the sole, wherein the barrier extends upwardly, forms a continuous loop around the foot bed area, is waterproof, and has a height everywhere in the range of 0.7-4 inches.
18. The flip flop sandal of claim 17 wherein the barrier height everywhere is in the range of 0.4-4 times a toe strap length.
19. The flip flop sandal of claim 17 wherein the sole comprises an upper sole and a lower sole, and the barrier comprises an attachment tab disposed between the upper sole and the lower sole.
20. The flip flop sandal of claim 17 wherein an outside surface of at least one of the foot straps is attached to an interior surface of the barrier.
21. The flip flop sandal of claim 17 further comprising a cover, wherein the cover is removably attachable to at least one of the foot straps.
Type: Application
Filed: Dec 27, 2015
Publication Date: Jun 29, 2017
Inventor: Dan Alan Steinberg (Blacksburg, VA)
Application Number: 14/979,469