Fin with a harmless foot pocket

Information

  • Patent Grant
  • 6276978
  • Patent Number
    6,276,978
  • Date Filed
    Wednesday, December 27, 2000
    24 years ago
  • Date Issued
    Tuesday, August 21, 2001
    23 years ago
Abstract
A fin is formed of a foot pocket that has a slit extended from one side to another side of the foot pocket along a joint of the foot pocket and a blade of the fin, so that a front part of the foot pocket forms a movable protective flap. The movable protective flap allows a diver to easily push it open with toes and to exert strength via instep against the foot pocket during kicking water. The movable protective flap provides sufficient space for toes to move in the foot pocket without being compressed while protects the diver's foot against rocks, coral reefs and the like and therefore allows the diver to kick water more powerfully. The movable protective flap also eliminates hard and sharp edge of the foot pocket to protect the diver's foot against cut, bruised or swollen instep that is in contact with the foot pocket.
Description




FIELD OF THE INVENTION




The present invention relates to a fin, and more particularly to a fin having a foot pocket that on the one hand comfortably covers and protects a diver's toes from harm and on the other hand enables the diver to force his instep against the foot pocket while kicking water.




BACKGROUND OF THE INVENTION




Conventional fins can be generally divided into two types, namely, a fin


10


with closed foot pocket


40


, as shown in

FIG. 1

, and a fin


20


with open foot pocket


40


, as shown in FIG.


2


. In both types, the foot pocket


40


is integrally connected to a blade


30


of the fin


10


,


20


. The closed foot pocket


40


of the fin


10


has a front portion


41


that is completely connected to the blade


30


without any opening between them and therefore encloses toes of a diver wearing the fin


10


in the foot pocket


40


. On the other hand, the open foot pocket


40


of the fin


20


has a front opening


42


between the foot pocket


40


and the blade


30


to expose the diver's toes.




As known by most people, in skin diving or other types of diving, the diver moves forward under water when he or her alternately swings two legs up and down to kick water. The diver's strength is transferred from thighs via shanks to insteps and toes, enabling insteps and toes to force against the foot pockets


40


and thereby bring the blades


30


to downward move against water. Please refer to FIG.


3


. For a diver wearing fins


10


with closed foot pockets


40


, when one of his or her two legs is moved downward to kick water, the leg's strength is transferred to toes


43


, forcing the same to press against the foot pocket


40


at an inner side of the front portion


41


thereof and bring the blade


30


to downward move against water. It is known that toes are the most vulnerable portions in human's feet. Improperly or overly applying a force with toes tends to cause tiredness and pain of feet. When the toes


43


forcefully press against the closed foot pocket


40


, the diver's sole arches to easily cause sprained toe joints as well as cramped foot and calf.




Please now refer to FIG.


4


. The open foot pocket


40


of the fin


20


allows toes


43


to expose from the front opening


42


thereof. When the diver wears fins


20


with open foot pockets


40


, his or her leg strength of the downward moved leg is transferred to an instep


44


of that leg, making the instep


44


a point of applying force. The instep


44


applies a force on the foot pocket


40


that transfers the force to the blade


30


to complete the movement of kicking water. Since the instep


44


is structurally stronger than toes


43


, it is more advantageous to move the blade


30


with the instep


44


than toes


43


. The fin


20


with open foot pocket has, however, a drawback of dangerously exposing toes


43


and a part of the instep


44


from the front opening


42


of the foot pocket


40


to rocks, coral reefs, sea urchins and the like under sea, resulting in cut wound and/or puncture wound at these areas. Moreover, the front opening


42


of the open foot pocket


40


has a hard and sharp front edge


45


that would be inevitably in contact with and abrade or otherwise compress the instep


44


at some fixed areas thereof when the latter exerts force against the foot pocket


40


, resulting in swollen, blistered, bruised skin and/or soreness and stiffness of the instep


44


. Such harms made by the open foot pockets


40


to the diver's insteps prevent the diver from kicking water with full strength and make diving less interesting.




SUMMARY OF THE INVENTION




It is a primary object of the present invention to provide a fin with a harmless foot pocket to eliminate the drawbacks of the conventional fin with closed or open foot pocket in causing tired and sore toes, sprained toe joints, cramped feet and calves, and wounded skin and cartilage at instep.




The fin with a harmless foot pocket according to the present invention mainly includes a foot pocket that has a slit extended from one side to another side of the foot pocket along a joint of the foot pocket and a blade of the fin, so that a front part of the foot pocket forms a movable protective flap. The movable protective flap allows a diver to easily push it open with toes and to exert strength via instep against the foot pocket during kicking water. The movable protective flap is large enough to provide sufficient space for toes to move in the foot pocket without being compressed while protects the diver's foot against rocks, coral reefs and the like and therefore allows the diver to kick water more powerfully. The movable protective flap also eliminates hard and sharp edge of the foot pocket to protect the diver's foot against cut, bruised or swollen instep that is in contact with the foot pocket.











BRIEF DESCRIPTION OF THE DRAWINGS




The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein





FIG. 1

is a perspective of a conventional fin with a closed foot pocket;





FIG. 2

is a perspective of a conventional fin with an open foot pocket;





FIG. 3

is a side view showing how a diver wearing the fin of

FIG. 1

forces his toes against the foot pocket while kicking water;





FIG. 4

is a side view showing how a diver wearing the fin of

FIG. 2

forces his instep against the foot pocket while kicking water;





FIG. 5

is a perspective of a fin having a harmless foot pocket according to the present invention; and





FIG. 6

is a partially sectioned side view showing how a diver wearing the fin of

FIG. 5

pushes a movable protective flap of the foot pocket open with toes and forces his instep against the foot pocket while kicking water.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Please refer to

FIGS. 5 and 6

in which a fin with a harmless foot pocket according to the present invention is shown. The fin mainly includes a foot pocket


1


that has a substantially semi-circular slit


3


extended from a predetermined point at one side to another predetermined point at the other side of the foot pocket


1


along a joint of the foot pocket


1


and a blade


2


of the fin, such that a front part of the foot pocket


1


forms a movable protective flap


4


integrally connected to the foot pocket


1


. The movable protective flap


4


enables the foot pocket


1


to function, on the one hand, like a closed foot pocket


40


on the fin


10


to protectively cover the diver's toes


43


and, on the other hand, like an open foot pocket


40


on the fin


20


to allow exposure of toes


43


to external environment without being compressed.




When a diver wearing fins of the present invention alternately forces two legs downward to kick water and thereby moves forward under water, his or her toes


43


of the downward moved leg would naturally and automatically push open the movable protective flap


4


and exert force via the instep


44


against the foot pocket


1


behind the movable protective flap


4


. Therefore, the foot pocket


1


not only provides sufficient space for toes


43


to move therein, but also allows the diver's instep


44


to exert more powerful strength against the blade


2


for the latter to downward move against water and push the diver forward under water. The movable protective flap


4


is large enough to normally protect the instep


44


and toes


43


against cut wound, puncture wound, and many other potential dangers when the diver is under water. The diver's instep


44


and toes


43


are completely located below the movable protective flap


4


and not in contact with any edge of the movable protective flap


4


. The instep


44


, when exerting force against the foot pocket


1


to move the blade


2


downward, is protected from undesired compression and abrasion due to the edge of the protective flap


4


and therefore enables the diver to continue kicking water for a prolonged time.




In an embodiment of the present invention, the movable protective flap


4


is provided with a plurality of air vents


5


of any shape. Air vents


5


increase a softness of the protective flap


4


and facilitate good water convection in the foot pocket


1


and draining of water from the foot pocket


1


to eliminate possible vacuum sucking effect in the foot pocket


1


when the diver pulls his or her foot out of the foot pocket


1


, particularly when the diver intends to end diving or is in an emergent condition during diving.




In implementing the present invention, the movable protective flap


4


may be made of a material thinner or softer than that for making the foot pocket


1


, so that the movable protective flap


4


could be more easily pushed open with toes


43


. Moreover, ribs


6


of suitable shape and dimensions may be provided at two ends of the slit


3


to prevent the movable protective flap


4


from easily breaking and separating from the foot pocket


1


at the two ends of the slit


3


.




The present invention has been described with a preferred embodiment thereof and it is understood that many changes and modifications in the described embodiment can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.



Claims
  • 1. A fin with a harmless foot pocket, comprising a foot pocket integrally connected to a blade of said fin, said foot pocket being characterized in that it has a slit extended from a predetermined point at one side to another predetermined point at the other side of said foot pocket along a joint of said foot pocket and said blade, such that a front part of said foot pocket forms a movable protective flap integrally connected to said foot pocket; and said movable protective flap allowing a diver to easily push it open with toes and to exert force via an instep against an area of said foot pocket behind said movable protective flap when the diver forces one leg wearing said fin downward to kick water.
  • 2. A fin with a harmless foot pocket as claimed in claim 1, wherein said movable protective flap is made of a material thinner or softer than that for making said foot pocket to enable easy pushing open of said movable protective flap with toes.
  • 3. A fin with a harmless foot pocket as claimed in claim 1, wherein said movable protective flap is provided with a plurality of air vents of any shape to enable good water convection in said foot pocket and good draining of water from said foot pocket and thereby avoids a vacuum sucking effect in said foot pocket when a diver pulls his leg out of said foot pocket.
  • 4. A fin with a harmless foot pocket as claimed in claim 1, wherein said movable protective flap is provided with ribs at two ends of said slit to protect said movable protective flap from easily breaking and separating from said foot pocket at the two ends of said slit.
US Referenced Citations (4)
Number Name Date Kind
3178738 Trell Apr 1965
3239857 Gwynne Mar 1966
4954111 Cressi Sep 1990
5108328 Hull Apr 1992