US20020106950A1

US20020106950A1 - Flipper

Info

Publication number: US20020106950A1
Application number: US10/015,170
Authority: US
Inventors: Le - Jang Feng
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-02-02
Filing date: 2001-10-22
Publication date: 2002-08-08
Also published as: TW462297U

Abstract

A flipper includes a foot pocket having a completely open front portion and a blade forward extended from two sides of the foot pocket, such that an opening is formed between the open front of the foot pocket and the blade to communicate an inner space of the foot pocket with a space behind the blade. A wearer's toes are exposed from the open front portion of the foot pocket to freely move in the opening and therefore lose an origin of force, making the wearer naturally apply forces from instep and plantar arch to move the blade downward and upward, respectively, and therefore be protected against sore and pain toe knuckles and convulsed calves, and allowed to dive for a prolonged time without consuming too much body strength.

Description

FIELD OF THE INVENTION

The present invention relates to a flipper, and more particularly to flipper that includes a foot pocket having a completely open front portion, so that a wearer in diving naturally uses his or her instep and plantar arch, instead of toes, to apply force to move the flipper upward and downward under water in an effort-saving manner without causing harm to feet.

BACKGROUND OF THE INVENTION

A conventional flipper usually includes integrally formed or firmly connected foot pocket 1 and blade 2, as shown in FIG. 1. A wearer puts the foot pocket 1 on his or her foot to control the upward and downward movements of the blade 2. When the blades 2 put on two feet are repeatedly and alternately moved upward and downward, the wearer is propelled forward under water. When the wearer alternately moves a flipper downward and upward, as shown in FIGS. 2 and 3, respectively, his or her foot 3 in the foot pocket 1 naturally applies forces at a closed front portion of the foot pocket 1 to move the blade 2. As can be seen from FIGS. 2 and 3, the closed front portion of the foot pocket 1 is the place at where the wearer's toes 31 locate. Thus, the wearer naturally uses toes 31 to apply forces to move the blade 2, and any reaction force from the blade 2 also acts on the toes 31. It is known that knuckles at toes 31 are very weak portions on a foot. Therefore, toes 31 tend to become sore and pain when they are frequently in a tightened state, as indicated by letter “a” in the figures, to apply forces for moving the blade 2 and bear reaction forces from the blade 2 from time to time under water. Since forces for moving the blade 2 are transferred from the wearer's calf to the toes 31, the calf would also become sore and pain or even convulsed in diving for a prolonged time. In brief, a diver wearing the conventional flipper with closed foot pocket 1 consumes more body strength and therefore could not dive too long. This is a major disadvantage of the conventional flipper with closed foot pocket 1.

FIG. 4 shows another conventional flipper that is designed to improve the conventional flipper of FIG. 1. The flipper of FIG. 4 includes a foot pocket 1 having an open upper front portion 11, via which a wearer's toes 31 extend from the foot pocket 1. When the wearer moves the flipper downward, as shown in FIG. 5, the toes 31 naturally bend downward without being confined by the open upper front portion 11 of the foot pocket 1. However, when the wearer moves the flipper upward, as shown in FIG. 6, the toes 31 would still contact with the blade 2 via the open upper front portion 11 and naturally become tightened to apply forces onto the blade 2. Thus, when the wearer moves the flipper of FIG. 4 upward under water, his or her sole would still become arched, as indicated by letter “a” in FIG. 6, to apply forces via the toes 31, and thereby consumes the wearer's body strength and results in sore, pain or even convulsed toes 31 and calf.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide an improved flipper that enables a wearer to naturally apply forces from instep and plantar arch, instead of toes, to move a blade of the flipper downward and upward, respectively, and therefore be protected against sore and pain toe knuckles and convulsed calf and would not consume too much body strength during a prolonged diving.

To achieve the above and other objects, the flipper of the present invention mainly includes a foot pocket having a completely open front portion and a blade forward extended from two sides of the foot pocket, such that an opening is formed between the open front of the foot pocket and the blade to communicate an inner space with a space behind the blade. A wearer's toes are exposed from the open front portion of the foot pocket to freely move in the opening and therefore lose an origin of force, making the wearer naturally apply forces from instep and plantar arch to move the blade downward and upward, respectively.

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 [0006]
FIG. 1 is a first conventional flipper, a foot pocket of which having a closed front portion; [0007]
FIG. 2 shows the condition of a wearer's foot applying forces to move the flipper of FIG. 1 downward; [0008]
FIG. 3 shows the condition of the wearer's foot applying forces to move the flipper of FIG. 1 upward; [0009]
FIG. 4 is a second conventional flipper, a foot pocket of which having an open upper front portion; [0010]
FIG. 5 shows the condition of a wearer's foot applying forces to move the flipper of FIG. 4 downward; [0011]
FIG. 6 shows the condition of the wearer's foot applying forces to move the flipper of FIG. 4 upward; [0012]
FIG. 7 is a perspective view of a flipper according to a first embodiment of the present invention; [0013]
FIG. 8 shows the condition of a wearer's foot applying forces to move the flipper of FIG. 7 downward; [0014]
FIG. 9 shows the condition of the wearer's foot applying forces to move the flipper of FIG. 7 upward; and [0015]
FIG. 10 is a perspective view of a flipper according to a second embodiment of the present invention.[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIG. 7 that shows a flipper according to a first embodiment of the present invention. The flipper of FIG. 7 includes integrally formed foot pocket [0017] 1 and blade 2 with the blade 2 forward extended from two sides of the foot pocket 1. A front portion of the foot pocket 1 is completely cut away to form an opening 10 communicating an inner space of the foot pocket 1 with a space behind the blade 2. A wearer's toes are completely exposed from the open front portion of the foot pocket 1 to freely move in the opening 10 and completely lose an origin of force due to the opening 10. This makes the wearer naturally use his or her instep and a middle portion of plantar arch corresponding to the instep to move the blade 2 downward and upward, respectively, as shown in FIGS. 8 and 9. The toes 31 are no longer tightened to apply forces for moving the blade 2 but freely extend from the opening 10 without being limited by the foot pocket 1 as otherwise would in the case of a foot pocket having a completely closed front portion or a partially opened upper front portion.
Since the instep and the plantar arch have a natural structure stronger than that of the toe knuckles in terms of applying forces to move the [0018] blade 2, and the opening 10 allows the toes 31 to naturally bend downward or upward without any restriction when the wearer moves the blade 2 downward or upward. The wearer needs not to tighten the toes 31 in an attempt to exert forces but easily and freely moves the blade 2 with the instep and the plantar arch in an effort-saving manner. Problems such as sore and pain toe knuckles and convulsed calves could therefore be avoided.
FIG. 10 shows a flipper according to a second embodiment of the present invention. In this second embodiment, the flipper includes a foot pocket [0019] 1 and a blade 2 that are separately manufactured and then connected together to form a complete flipper. Again, the foot pocket 1 has a front portion being cut away to form an opening 10 that communicates an inner space of the foot pocket 1 with a space behind the blade 2.
By wearing the flipper of the present invention, a diver is protected against sore and pain toes and convulsed calves to dive for a prolonged time without consuming too much body strength. [0020]

Claims

What is claimed is:

1. A flipper comprising a foot pocket having an open front portion, and a blade forward extended from two sides of said foot pocket, so that an opening is formed between said open front portion of said foot pocket and said blade to communicate an inner space of said foot pocket with a space behind said blade.

2. The flipper as claimed in claim 1, wherein said foot pocket and said blade are separately manufactured and then assembled to form a complete flipper, and said opening comprising said open front portion of said foot pocket.

3. The flipper as claimed in claim 1, wherein said foot pocket and said blade are integrally formed to provide a complete flipper, and said opening comprising said open front portion of said foot pocket and an open area on said blade immediately adjacent to said open front portion of said foot pocket.