Patent Application
20150196808
The present invention relates to fin accessories used in water related activities. More particularly, the present invention relates to swimming fins used for strength training in fitness swimming and performance swimming, which can enable a swimmer to swim faster and for longer periods of time when not using the fins.
There are various types of swimming and diving fins with diverse features and properties for use in pools and in the open water, by athletes, snorkelers, scuba divers, lifeguards, and others. Swimming fins are one type of fin that is used in fitness swimming or in performance training for competitive swimming sports. Such swimming fins can add resistance to a swimmer's kick and thereby provide the strength training that would ultimately allow a swimmer to swim faster and for longer than without the fins.
Swimming fins are primarily designed to increase the surface area of a swimmer's foot in order to add more propulsion force that would allow a swimmer to swim faster. Maintaining a higher speed of swimming generally requires more work and sustained exertion of energy from a swimmer, and thus can help build a swimmer's strength. For example, a swimmer attempting to swim at the same high speed without the fins would tire out faster and be unable to maintain that pace for a long period of time, and thus be unable to build the same amount of muscle as when using the fins. Thus, while swimming fins primarily cause a swimmer to swim faster when in use, they provide secondary benefits in gradual strength training. However, improvements can be made to conventional swimming fins that, for example, are designed with the primary goal of increasing swimming speeds rather than maximizing the resistance load to the swimmer's kick.
Various improvements have been made to swimming fins through the years, depending on their use and purpose. Certain improvements have been inspired by the natural swimming features of aquatic animals or marine mammals. For example, many swimming fins are based on the webbed footing design of animals such as ducks, which increases propulsion force by providing an improved oar-like pushing against the resistance of water and an improved recovery stroke. Other animals use different systems of propulsion based on a more flexible blade and a wing-like type of movement to simulate, for example, a whale's tail (see, e.g., U.S. Pat. Nos. 5,906,525; 5,906,525; 4,541,810) or a dolphin's tail (see, e.g., U.S. Pat. Nos. 2,321,009; 4,055,174). However, the features of small aquatic animals or large marine mammals are not always compatible with the biomechanics of a human swimmer. For example, the swimming fin shaped like a dolphin's tail disclosed in U.S. Pat. No. 4,055,174 achieves good aquatic properties, but by connecting the swimmer's feet together, forces the swimmer to kick in an unnatural and inefficient manner (and further precludes walking with the fins). While the ‘biomimicry’ of certain features in aquatic animals can be useful and may provide certain advantages in propulsion force or fluid dynamics that can improve a swimmer's kick, swimming fins should not so closely simulate the features of animals as to disregard the natural mechanical functions and balance of a human or cause a swimmer's body to be thrown off its ideal swimming position in the water.
Swimming fins are typically of one of two types—the closed foot type or the open heel type with a fastening strap. The closed foot type of fin is generally shaped like a shoe, with a cavity at the base shaped to fit a user's heel, and a foot pocket extending into the fin from the cavity. While the closed foot type has the advantage of providing stability and secure connection to the foot by providing a rigid edge to a user's heel and support to at least a part of the ankle, it does not allow much flexion to the ankle and thus inhibits the full extent of a swimmer's kick and natural swimming motions. The closed foot type of fin also has the disadvantage of being burdensome to manufacture because like regular shoes, it must be formed in various sizes to fit each individual foot size. However, open heel fins do not provide as much stability or security as the closed heel type of fin since they do not sufficiently support a swimmer's heels. In addition, the strap of an open heel fin may add stress to the back of a swimmer's heel, for example in the Achilles tendon area, and cause discomfort to a swimmer.
Thus, there is a need to address these and other problems to improve swimming fins for use as a training accessory for fitness and performance swimming, for the purpose of building the strength that can enable a swimmer to swim faster and for longer periods of time when not using the fins.
The present disclosure provides a swimming fin for building a swimmer's strength in fitness swimming and performance training. More particularly, embodiments of the present invention relate to a swimming fin comprising a fin body having top and bottom surfaces, proximal and distal sides, and lateral and medial sides, the fin body defining an opening at the proximal side and configured to receive a foot. According to an embodiment, a portion of a side of the fin body is scalloped.
According to one aspect, a portion of the lateral side and a portion of the distal side of the fin body are scalloped.
According to another aspect, the fin body comprises a flow channel extending across a portion of the top surface or a portion of the bottom surface of the fin body, the flow channel configured to direct water across the flow channel.
According to another aspect, the fin body comprises a first flow channel extending across a portion of the bottom surface and a second flow channel extending across a portion of the top surface of the fin body, wherein the first and second flow channels extend to an aperture formed through the top and bottom surfaces of the fin body, the first and second flow channels configured to direct water across the channels and through the aperture
According to another aspect, the swimming fin comprises a foot securing portion connected to the proximal side for securing a foot inserted into the fin body through the opening, wherein the foot securing portion comprises a back heel strap integrated with an under heel strap.
According to another aspect, the fin body is formed of a buoyant material.
According to another aspect, the buoyant material is an ethylene vinyl acetate (EVA) foam.
According to another aspect, the fin body defines a foot pocket configured to house a foot, and the foot pocket is molded by a foot last.
According to another embodiment of the invention, a swimming fin comprises a fin body having top and bottom surfaces, proximal and distal sides, and lateral and medial sides, the fin body defining an opening at the proximal side and configured to receive a foot. The fin body comprises a first flow channel extending across a portion of the top surface of the fin body or a portion of the bottom surface of the fin body, wherein the flow channel extends to an aperture formed through the top and bottom surfaces of the fin body, the flow channel configured to direct water across the flow channel and through the aperture.
According to one aspect, the flow channel is a planar groove extending from the lateral side of the fin body to the aperture positioned near the medial side of the fin body.
According to another aspect, the aperture is rectangular.
According to another aspect, the flow channel is tapered from one end near the aperture to another end on the fin body.
According to another aspect, the fin body further comprises a second flow channel extending across a portion of the top surface of the fin body, wherein the second flow channel extends to the aperture, the second flow channel configured to direct water across the channel and through the aperture, and wherein the first flow channel extends across a portion of the bottom surface of the fin body.
According to another aspect, wherein the fin body comprises a plurality of flow channels extending across a portion of the top surface of the fin body and a portion of the bottom surface of the fin body, and a plurality of apertures formed through the top and bottom surfaces of the fin body, wherein the channels in the plurality of flow channels extend to the apertures in the plurality of apertures.
According to another aspect, a portion of a side of the fin body is scalloped.
According to another aspect, the fin body is formed of a buoyant material.
According to another aspect, the swimming fin further comprises a foot securing portion connected to the proximal side for securing a foot inserted into the fin body through the opening, wherein the foot securing portion comprises a back heel strap integrated with an under heel strap.
According to another aspect, the fin body defines a foot pocket configured to house a foot, and the foot pocket is molded by a foot last.
According to another embodiment of the invention, a swimming fin comprises a fin body having top and bottom surfaces, proximal and distal sides, and lateral and medial sides, the fin body defining an opening at the proximal side and configured to receive a foot. The swimming fin comprises a foot securing portion connected to the proximal side of the fin body for securing a foot inserted into the fin body through the opening, wherein the foot securing portion comprises a back heel strap and an under heel strap.
According to an aspect, the under heel strap and the back heel strap are integrated with the fin body by a single material.
According to another aspect, the back heel strap comprises an opening extending across the back heel strap.
According to another aspect, the back heel strap comprises a plurality of openings extending across the back heel strap.
According to another aspect, a portion of a side of the fin body is scalloped.
According to another aspect, the swimming fin further comprises a plurality of flow channels extending across a portion of the top surface of the fin body and a portion of the bottom surface of the fin body, and a plurality of apertures formed through the top and bottom surfaces of the fin body, wherein the channels in the plurality of flow channels extend to the apertures in the plurality of apertures.
According to another embodiment of the invention, a swimming fin comprises a fin body having top and bottom surfaces, and proximal and distal sides, and lateral and medial sides, the fin body defining an opening at the proximal end and configured to receive a foot. The swimming fin comprises a foot securing portion connected to the proximal side of the fin body for securing a foot inserted into the fin body through the opening, wherein the fin body defines a foot pocket configured to house a foot, and the foot pocket is formed by a foot last.
According to an aspect, the fin body comprises a gripping mechanism positioned near the opening and configured to allow a user to pull the fin body over a foot.
According to another aspect, the gripping mechanism comprises a hole formed through the top surface of the fin body and configured to allow insertion of a finger through the hole.
According to another aspect, the foot pocket is configured to accommodate a user's instep and arch.
According to another aspect, a portion of a side of the fin body is scalloped.
According to another aspect, the swimming fin further comprises a plurality of flow channels extending across a portion of the top surface of the fin body and a portion of the bottom surface of the fin body, and a plurality of apertures formed through the top and bottom surfaces of the fin body, wherein the channels in the plurality of flow channels extend to the apertures in the plurality of apertures.
These and other advantages of the present invention will be readily understood with reference to the following specifications and attached drawings wherein:
a-5b show an illustration and a rendering of a pectoral fin of a humpback whale, as emulated by an embodiment of the invention.
c is a perspective schematic view of a pectoral fin of a humpback whale.
d shows a blade manufactured with a scalloped edge for use in turbines and other industrial applications.
a is a perspective schematic view of the direction of flow of a fluid over a straight edge.
b is a perspective schematic view of the direction of flow of a fluid over a scalloped edge.
a-7b are perspective schematic views of the direction of flow of a fluid over an inverted chamber.
c-7d show perspective schematic views of the direction of flow of a fluid over an inverted chamber with a release valve.
a-9j are cross sectional views of a swimming fin according to the embodiment of
Embodiments of the present invention will be described herein with references to the accompanying drawings.
According to an embodiment, the swimming fin 100 may include an irregular edge 102. In particular, the irregular edge 102 has a scalloped shape according to the embodiment shown in
Although not limited to theory, it has been reported that the tubercles of the humpback whale's pectoral fins increase propulsion. For example, the tubercles increase the surface area at the edge of the pectoral fin and can thereby cause more water to flow over its irregular edge than over a smooth edge. The increased surface area of the tubercles would thus require the fin to push against more water and accordingly increase propulsion. Moreover, as shown in
The scalloped edge 102 according to an embodiment of swimming fin 100 emulates the pectoral fin of the humpback whale to incorporate its unique properties. In particular, the scalloped edge 102 is believed to provide more surface area than a smooth edge, which can cause more water to flow over the scalloped edge and require the swimming fin to push against more water than a smooth edge would. For example, a fin with a straight edge would cause minimal propulsion and minimal lift forces. As shown in
In addition, an irregular edge that is scalloped and emulates the shape of a whale's fin is superior to an irregular edge that is webbed, as seen in conventional fins. In particular, the scalloped edge breaks the surface tension of water more efficiently than a webbed edge. A webbed fin or paddle is essentially like a ping pong paddle with inferior surface break geometric characteristics. In contrast, the scalloped edge allows for a lower resistance on its initial entry into the water, and thus breaks the surface faster with minimized resistance. Once submerged, the drag created by the scalloped edge can be as efficient or less efficient as a webbed edge; however, there is a significant advantage in the flow of momentum, as a result of the consistent momentum that the scalloped edge creates. For example, when a swimmer kicks, his foot may come slightly out of the water and when traveling through ambient air, will move at high speeds with minimal resistance. When the swimmer's foot re-enters the water surface, there is an immediate and sharp decrease in momentum. A webbed fin is likewise highly disruptive. The scalloped edge, however, does not cause as disruptive a loss in momentum, because of its ability to break the water tension, and allows for a more uniform speed. Moreover, as the swimmer kicks and alternates the direction of his foot upward and downward, he likewise has to break momentum with alternating directions of drag force. The scalloped edge allows for more uniform, and less disruptive momentum changes during kick. Thus, the scalloped edge according to embodiments of the invention provide advantages over the webbed edges of conventional designs.
According to an embodiment, a scalloped edge provides a repeating pattern of generally convex tubercles or protrusions extending from an otherwise planar edge. According to the embodiment shown in
According to another embodiment, the swimming fin 100 may include valves, apertures, or tapered holes 104 that go through the top and bottom surfaces of the fin, and positioned near a medial side (right, as shown) of the fin. The valves 104 are designed to create greater resistance and buoyancy to the fin. For example, as shown in
In contrast, as shown in
Thus, the valves 104 along a medial side (right, as shown in
According to another embodiment, the swimming fin 100 may include flow channels 106 across a surface of a fin. The flow channels 106 may be formed by grooves on a surface of the fin to guide the flow of water in a desired direction, for example, toward the open valves 104 as shown in
According to another embodiment, the swimming fin 100 may include a heel strapping system that is made of two components—an under heel strap 112 and a back heel strap 110. Thus, the heel strapping system according to an embodiment can add stability and comfort both under the heel and at the Achilles tendon area, and thus help reduce foot cramping or discomfort. As further shown by a rear view of an embodiment shown in
But in addition, there is often a lot of stress on the heel strap of conventional open heel fins, which can cause discomfort or pain to a swimmer and even cause blisters to form at the Achilles tendon area of the ankle. To address this problem, the back heel support strap 110 of the heel strapping system according to embodiments of the invention can be further latticed to flex and articulate around various shapes of ankle bones and Achilles tendons, thus reducing pain and friction. The latticing can take various shapes and forms. According to an embodiment, the heel strapping system, including the lattice features, are all integrated by a single material. Thus, according to an embodiment as shown in
According to another embodiment, the swimming fin 100 may include a grab-hole 114 at the instep, or at the top planar surface near the opening of the foot pocket 116, as shown in
b shows a cross sectional view of the under heel support portion (112 in
d shows a cross sectional view of a portion of the fin around the grab-hole opening (114 in
As noted above and addressed by various features according to embodiments of the invention, buoyancy is an important property of swimming fins. In particular, a swimmer must overcome the resistance caused by the upward force of a buoyant fin on the down-kick, which results in strength training and a faster and stronger kick while not wearing the fins. However, while embodiments of the invention provide for various features to increase the buoyancy of the fin, swimming fins according to embodiments may also be inherently buoyant by being made of highly buoyant material. The inherent buoyancy of the fins also helps naturally elevate the hips and feet of the swimmer to enforce proper body alignment and ideal horizontal body position in the water, even when the swimmer is not utilizing the various other features of the fin that promotes higher resistance, propulsion force and swimming speed. Moreover, swimming fins should not be so complex, burdensome or overly faithful to the biomechanics of an aquatic animal, as to distort a swimmer's natural swimming position in the water. Swimming fins according to embodiments may be viewed as lightweight extensions of the feet that can easily mimic a swimmer's natural kicking positions.
Thus, according to one embodiment, the swimming fin may be molded from a buoyant material such as an ethylene vinyl acetate (EVA) foam. EVA also has the advantage of being durable, rigid, and not easily subject to fatigue. According to other embodiments, the swimming fin may be made of other buoyant materials, such as TPR and PE foam. According to other embodiments, the swimming fin may be made of other materials, including but not limited to polyvinyl chloride, polyethylene, polypropylene, and other rubber and polymeric materials. According to other embodiments, the swimming fin may include composites or laminates such as fiber glass, reinforced plastic or graphite composites. According to embodiments, the entire swimming fin including the fin body and the dual-strapping system may be formed of a single integrated molded material for example, by being molded from conventional injection technology or injection molding technology. The swimming fin can be of any desired elasticity or stiffness, but is preferred stiff so as to resist stress fatigue.
According to an embodiment, the shape of the foot pocket or cavity of the swimming fin may be improved by forming the fin with a footwear last, thus improving the comfort level of the inner foot pocket. A footwear last is a mechanical form having the shape of a human foot and made of a hard material such as wood, iron or high density plastic, as shown in
While the present invention has been described with respect to what are currently considered to be the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The scope of the following claims is to be accorded the broadest interpretation, so as to encompass all such modifications and equivalent structures and functions.
