WO2011134066A1

WO2011134066A1 - Swim fin device

Info

Publication number: WO2011134066A1
Application number: PCT/CA2011/000489
Authority: WO
Inventors: Terry Nieforth
Original assignee: Terry Nieforth
Priority date: 2010-04-29
Filing date: 2011-04-28
Publication date: 2011-11-03

Abstract

A swim fin device for reducing ankle strain, comprising: a) a fin member consisting of a webbed member and a foot-receiving portion affixed to the webbed member; b) a shin member having shin attachment means for attachment to a shin; and c) a connecting member, connecting the webbed member to a central portion of the shin attachment member; wherein the webbed member extends a maximum of about 180° from a user's tibia.

Description

SWIM FIN DEVICE

TECHNICAL FIELD

The present disclosure relates to a swim fin device. In particular, the disclosure relates to an improved foot-mounted swim fin with a lower leg binding that provides greater thrust while lowering strain on the ankle joint.

BACKGROUND

Scuba diving and snorkelling are two popular activities where foot-mounted swim fins are used as a means to increase the propelling force through the water. Typically, a foot- mounted swim fin comprises a webbed member and a means to affix a swimmer's foot to the webbed member. The webbed member increases the volume of water displaced during the kicking motion, which results in the swimmer having an increased acceleration and propulsion through water.

Traditional foot-mounted swim fins have been designed with the webbed member rigidly affixed to a foot-receiving portion or boot. The swim fin is then secured to the foot via a strapping means around the back of the heel. To achieve the maximum propelling force from the foot-mounted swim fin, and to reduce drag, it is desirable to have the webbed member substantially parallel or in-line with the swimmer's tibia. This increases the force of the kicking motion and reduces drag during coasting. However, in order to achieve this configuration with traditional foot-mounted swim fins, a great strain is imposed on the swimmer's ankle during the kicking motion.

U.S. Patent No. 4,017,925 (Shamlian) issued April 19, 1977, discloses a swim fin with members provided for maintaining a swimmer's foot in a predetermined angular relationship with respect to a swimmer's leg. The ankle movement restrictor attachment for the swim fin uses a shin brace with straps or tubular assembly pivoted to the rear of the fin and the restrictor can be positioned to fit around the back of the swimmer's leg. United States Patent Application (McCarthy, 2007) No. 2007/0032148 discloses an adjustable heel strap having an adjustable instep strap connected to the heel strap adjacent the heel portion of a swimmer's foot. A method is also disclosed, for a multi-dimensional heel strap having an adjustable instep strap connected to the heel strap adjustability around the ankle and instep to reduce ankle strain, increase ankle support and distribute load and stress points.

United States Patent No. 5,632,662 (Cadorette, 1997) discloses a centrally articulated swim fin that comprises a boot portion to receive the foot of a swimmer, a webbed portion, and a pair of side members. Each of the side members has an upper and lower arm and an upper and lower end. The lower ends of the side members are attached to opposite sides of the webbed portion while the upper ends of the side members attached to a leg engaging strap. A pivot means connects the side members to the boot portion and permits the side members and the webbed portion to rotate about the boot portion such that when the leg engaging strap is attached to the lower leg of a swimmer the webbed portion is pivoted to a position approximately parallel to the swimmer's lower leg.

United States Patent No. 4,869,696 (Ciccotelli, 1989) discloses a swim fin designed not to snag seaweed., having a rigid blade that has the center portion of its leading edge pivotally attached to two beams which project forwardly from the foot pocket.

United States Patent No. 6,193,636 (Chen, 2001) discloses a swimming auxiliary device that includes an attaching member an attaching member mounted to the swimmer's calf or forearm, and a connecting device connected to the attaching member so as to pivotally connect a webbed member to the attaching member. A pulling device is connected between the webbed member and the attaching member to pull the webbed member toward the attaching member.

United States Patent Publication No. 20100075554 (Johnson, published March 25, 2010) discloses swim fins that attach to the legs of a swimmer and allow the swimmer to walk barefoot on a surface without the fin contacting the surface. A few problems encountered in the prior art include the webbed member not being substantially parallel or in-line to the swimmer's tibia - in particular, the rotation of the ankle is sometimes over-extended so that the webbed member is extended more than 180° from the swimmer's tibia; the foot-receiving portion not being optimally positioned to reduce drag; the webbed member not being optimally positioned to reduce drag; and a lack of substantive ankle support. These problems result in a greatly reduced swimming efficiency, and in some cases, cause pain and discomfort in and around the ankle area. There is a need for a foot-mounted swim fin that reduces ankle stress, and lowers drag, while maintaining and/or increasing the propelling force.

SUMMARY

The swim fin device of the present invention provides a superior way to achieve comfort, thrust and speed for a swimmer. The swim fin device binds to the lower leg of a swimmer, so as to reduce chafing and/or blistering to the foot area (e.g. the heel), by reducing and/or eliminating ankle strain, and by reducing drag. The swim fin device also increases thrust potential by optimizing the position of the webbed member. In one aspect, there is provided a swim fin device comprising: a) a fin member consisting of a webbed member and a foot-receiving portion affixed to the webbed member; b) a shin member having shin attachment means for attachment to a lower leg and c) a connecting member, connecting the webbed member to a central portion of the shin attachment member; wherein the webbed member extends a maximum of about 180° from a user's tibia.

A first end of the connecting member can be pivotally attached to a top surface of the fin member; while a second end of the connecting member can pivotally and slidingly engaged with a central portion of the shin member. The first end of the connecting member may be removably attached to the fin member. Preferably, a hinge is used to attach the first end of the connecting member to the fin member. Alternatively, the connecting member can consist of a plurality of inter-linked members.

The webbed member and foot-receiving portion may be formed as a single piece. The foot-receiving portion may be secured to a user's foot or ankle. The shin member may include padding on an inner surface thereof.

In another aspect, there is provided a swim fin device comprising: a) a fin member consisting of a webbed member and a foot-receiving portion affixed to the webbed member; b) a shin member having shin attachment means for attachment to a lower leg; and c) a connecting member for connecting the webbed member to the shin member; wherein a first end of the connecting member is pivotally attached to a top surface of the fin member; and a second end of the connecting member is pivotally and slidingly engaged with a central portion of the shin member.

The second end of the connecting member may include a pivot means that engages with a first pair of longitudinal slots in the shin member, with the connecting member engaging with a third longitudinal slot in the shin member. Furthermore, the first end of the connecting member may be removably attached to the fin member. A hinge may be used to attach the first end of the connecting member to the fin member.

The webbed member and foot-receiving portion may be formed as a single piece. The foot-receiving portion may be secured to a user's foot or ankle. It is preferable for the webbed member to extend to a maximum angle of about 180° from the user's tibia. The shin member may comprise padding on an inner surface thereof. Preferably the shin member is made of a material that is lightweight, rigid and waterproof. This material may be selected from the group consisting of aluminum, plastic carbon fibre and stainless steel. BRIEF DESCRIPTION OF DRAWINGS

Embodiments of the present invention will be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 illustrates a side view of an embodiment of the present invention attached to a swimmer's leg.

Figure 2 illustrates the embodiment of Figure 1 , in which the webbed member is maximally extended.

Figure 3 illustrates a front view of the embodiment shown in Figure 2.

Figure 4 illustrates a perspective view of a webbed member, connecting member and shin member.

Figure 5 illustrates an exploded view of Figure 4. DETAILED DESCRIPTION

The following is given by way of illustration only and is not to be considered limitative.

Figures 1 to 3 illustrate various views of an embodiment of the present invention. Figure 1 is a front view of an embodiment of the swim fin device (10) attached to the leg of a swimmer. The device (10) comprises a fin member (15), a connecting member (20) and a shin member (25). The fin member (15) includes a webbed member (30) and a foot- receiving portion (35) to fully enclose and secure the foot.

Figure 2 shows the maximum extension of the webbed member (30) as being

substantially parallel to the swimmer's tibia. In other words, the swim fin device allows for a maximum displacement of about 180° between the webbed member (30) and the swimmer's tibia. The flexion angle (Θ) is defined as the angle between the plane of the webbed member (30) and the plane of the tibia. Figure 1 illustrates the configuration where the flexion angle (Θ) is about 90°. Figs. 2 and 3 illustrate the configuration where the flexion angle (Θ) is about 180°.

The webbed member (30) can rotate between a minimum angle (Oi) and maximum angle (θ₂). The minimum angle (θι) is defined as the angle between the plane of the webbed member and the plane of the tibia, when the swimmer's foot is rotated as much as possible toward the shin. The maximum angle (θι) is defined as the angle between the plane of the webbed member and the plane of the tibia, when the swimmer's foot is rotated as much as possible away from the shin. As illustrated in Figs. 2 and 3, the maximum flexion angle (θ₂) is set to a value of about 180°. This maximum value of the flexion angle (0₂ = 180°) prevents the ankle joint from being hyper-extended, and allows the swimmer to achieve the maximum propelling force from the device.

The swim fin device (10) can use any type of fin member (15). For example, the webbed member (30) and the foot-receiving portion (35) can be made from a flexible material, such as, for example, rubber; or the webbed member (30) can be rigid; or the webbed member (30) can be made more rigid than the foot-receiving portion (35). The webbed member (30) may ideally approximate a dolphin's tail.

The webbed member (30) and the foot-receiving portion (35) may be formed as two pieces and are operably rigidly affixed together, or may be formed as a single piece, as shown in Figs. 1 to 3. The foot-receiving portion (35) may also be formed to partially enclose the foot and have a strapping means (not shown) around the heel or ankle, to ensure a secure and tight fit so that the swimmer's foot is held in position in relation to the foot receiving portion (35) and webbed member (30).

The webbed member (30) can be at an angle with respect to the foot-receiving portion (35) such that when the swimmer's foot is maximally extended, the webbed member (30) is substantially parallel or in-line with the swimmer's tibia. When the webbed member (30) is angled below the foot-receiving portion (35), the angle between the webbed member (30) and the foot-receiving portion (35) is preferably from about 20° to about 30°. The shin member (25) can be made from a durable waterproof material or any

combination thereof, such as, for example, stainless steel or plastic, and even more preferably made from a lightweight waterproof material or any combination thereof, such as, for example, fibreglass or carbon fibre. The shin member (25) can have a gel padding, a foam padding or the like affixed to the inside, allowing for greater comfort during use.

As shown in Figs. 1 -3, the shin member (25) is preferably positioned on the front side of the lower leg over the shin bone area. The shin member (25) can extend from a position just below the knee cap down to the ankle area and does not interfere with the connection point (65) on top of the foot when the foot is rotated as much as possible toward the shin (i.e. when the flexion angle is at its minimal value of θι). The connection point (65) refers to the connection point between the connecting member (20) and the fin member (15). The underside of the shin member (25) is formed to fit the shin area. The profile of the shin member (25) is shaped to minimize drag in the water while the swimmer's leg is moving during a scissor kick, or the like.

The shin member (25) is affixed to the lower leg of the swimmer, preferably at the narrowest part of the ankle, and below the knee cap (i.e. at the top of the calf muscle on the back of the leg). Leg strapping means (95) can affix the shin member (25) to the lower leg of the swimmer. The leg strapping means (95) may be made of any material that conforms to the leg, for example, fabric and zipper; or straps and buckles; or any other suitable material. As an example, a fabric sheath (not shown) having, for example, a zipper, may extend the entire length of the shin member (25) and around the back of the lower leg. It is understood that any other configuration that rigidly holds the shin member (25) tightly in place may be used. The connection point (65) may be formed on the top of the fin member (15), so as to provide comfort and to keep the connecting member (20) in line with the shin member (25). The connection point (65) is preferably positioned at the top of the foot as close to the ankle as possible in such a way that the connection point (65) does not interfere with the swimmer's ankle, foot, lower leg or the shin member (25), when the flexion angle ranges from its minimal value (θι) and its maximal value (θ₂). This range of motion of the swimmer's foot (i.e. the flexion angle repeatedly moving between θι and θ₂) is necessary for swimming with the swim fin device of the present invention (and, with a traditional swim fin, for that matter).

Figures 4 and 5 illustrate one configuration of the connecting member (20) in relation to the fin member (15) and shin member (25). For clarity, only the webbed member (30) is shown. However, it is understood that the fin member (15) includes both a webbed member (30) and a foot-receiving portion (not shown in Figs. 4 and 5), as depicted, for example, in Figs. 1 to 3.

The connecting member (20) is pivotally attached at one end to a top surface of the fin member (15). In the embodiment shown in Figs. 4 and 5, a hinge mechanism (60) is formed on the fin member (15), to allow the fin member (15) to rotate relative to the hinge mechanism (60). Alternatively, the hinge mechanism (60) can be formed in such a way as to allow the fin member (15) to detach from the hinge mechanism (60), and allow for an interchange of fin member (15) styles.

The connecting member (20) may be made of material suitable for sustaining forces experienced when swimming, such as, for example, aluminum, stainless steel or carbon fibre.

The connecting member (20) is pivotally and sliding engaged to the shin member (25). As shown in Figs 4 and 5, the connecting member (20) is pivotally engaged with a corresponding pair of longitudinal slots (75, 80) of the shin member (25), so as to be able to pivot and slide. In Figs. 4 and 5, the pivot means (70) of the connecting member (20) consists of a tubular member (55) that engages a hole (57) in the connecting member (20) and the longitudinal slots (75, 80) of the shin member (25). There are alternate types of pivot means, such as, for example but not limited to, the connecting member having a pair of pivot members at its extremity. The shin member (25) is also adapted with another longitudinal slot (85) adapted to receive the connecting member (20). The combination of the multiplicity of longitudinal slots (75, 80, 85) and pivot means (70) allows the connecting member (20) to slide and pivot in relation to the shin member (25) for easily allowing the webbed member (30) to repeatedly move between the flexion minimum and maximum angles of θι and θ₂.

The connecting member (20) and its pivot means (70) are able to slide and pivot in their respective longitudinal slots (75, 80 and 85). The portion of the connecting member (20) nearest to the swimmer's foot can protrude from its longitudinal slot (85) as required, in order to allow the swimmer's foot to rotate towards the lower leg (i.e. the flexion angle approaches its minimum value θι). When the swimmer's foot rotates in the opposite direction (i.e. the flexion angle approaches its maximum value 0₂) and becomes maximally extended, the pivot means (70) of the connecting member (20) stop against the lower portion of the pair of longitudinal slots (75, 80). The connecting member (20) is also stopped at a predetermined point on the shin member (25) at the portion nearest to the ankle. At the same time, the connecting member (20) prevents the hinge mechanism (60) on top of the swimmer's foot from rotating past a maximum predetermined allowable angle, which is similar to the maximum value of the flexion angle 0₂.

In another embodiment (not shown), the connecting member (20) can consist of a multiplicity of inter-linked members, rigidly affixed at both ends thereof to the fin member (15) and the shin member (25). This type of connecting member also maintains a flexion angle range between a minimum value and maximum value of about 180°.

Both of the stops described above prevent hyper-extension of the ankle joint. They also distribute the force generated by the webbed member (30) away from the ankle joint over the length of the lower leg via the shin member (25). The forces are transferred through the hinge mechanism (60) through the connecting member (20) through the shin member (25), and finally onto the lower leg of the swimmer.

Chafing and blistering of the heel are essentially eliminated. Substantially more force from the swimmer's upper leg can be transferred to the fin member (15) during the scissor-kicking motion of the swimmer. All critical components may consist of any suitable metal, plastic, composite, carbon fiber, etc., or any combination thereof.

Padding may be added in certain areas where contact is made with the swimmer's body. Various adjusting mechanisms may be added to allow for adjustability to the stop point positions on the swim fin device.

Although embodiments of the invention have been described above, it is limited thereto and it will be apparent to those skilled in the art that numerous modifications form part of the present invention insofar as they do not depart from the scope of the claimed and described invention.

CONCLUSION

The foregoing has constituted a description of specific embodiments which are only exemplary. The invention in its broadest, and more specific aspects, is further described and defined in the claims which now follow.

Claims

CLAIMS:

1. A swim fin device comprising:

a) a fin member consisting of a webbed member and a foot-receiving portion affixed to the webbed member;

b) a shin member having shin attachment means for attachment to a lower leg; and

c) a connecting member, connecting the webbed member to a central portion of the shin attachment member; wherein

the webbed member extends a maximum of about 180° from a user's tibia.

2. The swim fin device of claim 1, wherein a first end of the connecting member is pivotally attached to a top surface of the fin member; and a second end of the connecting member is pivotally and slidingly engaged with a central portion of the shin member.

3. The swim fin device of claim 2 or 3, wherein the first end of the connecting member is removably attached to the fin member.

4. The swim fin device of any one of claims 1 to 4, wherein a hinge is used to attach the first end of the connecting member to the fin member.

5. The swim fin device of claim 1 , wherein the connecting member consists of a

plurality of inter-linked members.

6. The swim fin device of any one of claims 1 to 5, wherein the webbed member and foot-receiving portion are formed as a single piece.

7. The swim fin device of any one of claims 1 to 6, wherein the shin member comprises padding on an inner surface thereof.

8. The swim fin device of any one of claims 1 to 7, wherein the foot-receiving portion is secured to a user's foot or ankle.

9. A swim fin device comprising:

c) a connecting member for connecting the webbed member to the shin member; wherein

a first end of the connecting member is pivotally attached to a top surface of the fin member; and a second end of the connecting member is pivotally and slidingly engaged with a central portion of the shin member.

10. The swim fin device of claim 9, wherein the second end of the connecting member includes a pivot means that engages with a first pair of longitudinal slots in the shin member, and the connecting member engages with a third longitudinal slot in the shin member.

1 1. The swim fin device of claim 9 or 10, wherein the first end of the connecting member is removably attached to the fin member.

12. The swim fin device of any one of claims 9 to 1 1 , wherein a hinge is used to attach the first end of the connecting member to the fin member.

13. The swim fin device of any one of claims 9 to 12, wherein the webbed member and foot-receiving portion are formed as a single piece.

14. The swim fin device of any one of claims 9 to 13, wherein the webbed member

extends to a maximum angle of about 180° from the user's tibia.

15. The swim fm device of any one of claims 9 to 14, wherein the shin member comprises padding on an inner surface thereof.

16. The swim fin device of any one of claims 9 to 15, wherein the shin member is made of a material that is lightweight, rigid and waterproof.

17. The swim fin device of claim 16, wherein the material is selected from the group consisting of aluminum, plastic, carbon fibre and stainless steel.

18. The swim fin device of any one of claims 9 to 17, wherein the foot-receiving portion is secured to a user's foot or ankle.