Abstract: Aquatic activity fin (1) comprising a foot support portion (2) configured for fixing to a person's foot, and a fin portion (3) extending from the foot support portion substantially along a base plane (P). The fin portion (3) comprises a support frame (4), a plurality of hydrofoil blades (5) mounted pivotally to the support frame (4) via pivot couplings (6), and a mechanism for limiting the maximum blade pivot angle ? of each hydrofoil blade. The mechanism for limiting the maximum blade pivot angle comprises bidirectional angle stops (7) configured to allow pivoting of the hydrofoil blade from the a thrust position where a trailing edge (9b) of the hydrofoil blade is above said base plane (P), to a return position where the trailing edge (9b) is below said base plane (P).

Abstract: One embodiment of improved swim fins consists of a right foot attachment (101) with an outer right blade (111) and an inner right blade (112) which is arranged such that it does not mechanically interfere with an inner left blade (113). The blades may include a pivot mechanism (220) that allows the blades to maintain an optimal angle of attack as the swimmer moves their legs up and down. In another embodiment, a right blade (1011) and a left blade (1013) are attached to the feet of a person who is propelled by the blades above the surface of the water as they pump their feet up and down, forming a human-powered hydrofoil. Other embodiments are described and shown.

Abstract: An exoskeleton boot that can be selectively coupled to and decoupled from a lower link of an exoskeleton includes an upper configured to receive a foot of a human user and an outsole coupled to the upper. An exoskeleton connection interface is structurally coupled to the outsole and has a locked mode and an unlocked mode. In the locked mode, the exoskeleton connection interface is configured to inhibit decoupling from a boot connection interface of an exoskeleton link. In the unlocked mode, the exoskeleton connection interface is configured to facilitate decoupling from the boot connection interface.

Abstract: A configurable wearable apparatus for water sports includes a boot and a fin pivotably attached to the boot. In a first configuration, the fin is oriented towards the toe portion of the boot. In a second configuration, the fin is oriented towards the heel portion of the boot. The fin can be attached to the boot by rods having first and second ends. The first end of each rod is attached to the fin and the second end of each rod is attached to a pivot point on the side of the boot. The second end of the rods can be releasably secured to the toe portion or to the heel portion of the boot with press-fit or friction-fit assemblies.

Abstract: A monofin has a fin having a left fluke, and right fluke, and a hinge section that hingedly connects the left fluke and the right fluke. The monofin also includes a left foot pocket connected to the left fluke, a right foot pocket connected to the right fluke, and a hinge assembly that hingedly connects the left foot pocket and the right foot pocket.

Abstract: Provided is a swimming fin system that includes a boot portion and a lower leg portion for improved swimming efficiency and normal ambulation over dry land. The lower leg portion comprises a substantially cylindrical sleeve configured to receive the lower leg of a wearer and support a pair of laterally extending fin members. The fin members are substantially rectangular and do not overlap the swimmer's ankle or foot. Each boot portion receives the foot and heel of the wearer, while supporting a pair of substantially rectangular fin members that extend from the lateral sides of the boot. The fins do not extend substantially beyond the toes of the wearer. While donned, the fins of the boot and lower leg portions can be angled relative to one another during kicking motions, while the fins of the boot portions do not interfere with a user's gait over dry land.

Abstract: Collapsible, adjustable scuba fin with a cam lock feature. The blades of the fin are set on an enclosed track in the foot plate which allows the blades to be extended to create a fin of variable surface area for different swimming conditions or retracted under the foot plate for walking. The blades can be locked in place by the cam lock which is attached to the foot plate by means of a screw and foot pocket by means of an adjustable pull lanyard. The foot pocket and heel hilt can be adjusted to accommodate feet and footwear of varying size, and style allowing a single fin to fit multiple individuals and requirements. A T-bolt slider set in the foot plate can be rotated or removed to access the space between the blades allowing for the clearing of debris.

Abstract: Swim fin (1) comprising a foot portion (2) intended to accommodate and be attached to a user's foot, which foot portion (2) embraces at least one toe portion (3) having a foot sole, at least one arm (4), which is attached to the foot portion (2) and which projects forward, and at least one blade (5), the at least one blade (5) being limitedly pivotally attached to the arm (4). The arm (4) is rigidly attached to at least the toe portion (2) while forming an angle (?) defined as the angle between the foot sole and the axial direction of the arm (4), which angle amounts to between approx. 20 and 60°, and that the arm is rigid.

Abstract: Disclosed is a buckle device that releasably locks an elastic band including a plurality of engaging portions in a lengthwise direction. The buckle device includes a buckle holder and a pair of slide buckles slidably fitted to the buckle holder. The buckle holder includes a pair of locking pins apart from each other and a pair of guide surfaces. A pair of elastic bands are hung on the locking pins respectively. The guide surfaces are inclined in opposite directions with respect to a plane passing through the pair of the locking pins. The slide buckle has a ratchet protrusion configured to engage the engaging portion of the elastic band and a slide surface configured to come into surface contact with the guide surface of the buckle holder.

Abstract: A detachable swim fin includes a foot pocket and a fin blade. The fin blade is movably connected to the foot pocket through a locking buckle mechanism. With the detachable design of the fin blade and the foot pocket, the present invention provides an amphibious function. When they are detached, the foot pocket is capable of protecting the foot when walking on land, like a beach shoe or a fishing shoe. When they are assembled, the present invention is used as a swim fin. When going out, the user could take apart the swim fin for carrying conveniently and flexibly. This provides a compact and light design.

Abstract: An apparatus includes an upper portion, a sole and a fin. The upper portion is configured to at least partially cover a foot. The sole is coupled to the upper portion and defines a cavity. The fin has a first portion and a second portion. The fin is movable between a first configuration and a second configuration. When in the first configuration, the fin is substantially within the cavity defined by the sole, and the first portion of the fin at least partially overlaps the second portion of the fin. When in the second configuration, the fin extends substantially outside the cavity defined by the sole.

Abstract: A detachable swim fin includes a foot pocket and a fin blade. The fin blade is movably connected to the foot pocket through a locking buckle mechanism. With the detachable design of the fin blade and the foot pocket, the present invention provides an amphibious function. When they are detached, the foot pocket is capable of protecting the foot when walking on land, like a beach shoe or a fishing shoe. When they are assembled, the present invention is used as a swim fin. When going out, the user could take apart the swim fin for carrying conveniently and flexibly. This provides a compact and light design.

Abstract: An apparatus includes an upper portion, a sole and a fin. The upper portion is configured to at least partially cover a foot. The sole is coupled to the upper portion and defines a cavity. The fin has a first portion and a second portion. The fin is movable between a first configuration and a second configuration. When in the first configuration, the fin is substantially within the cavity defined by the sole, and the first portion of the fin at least partially overlaps the second portion of the fin. When in the second configuration, the fin extends substantially outside the cavity defined by the sole.

Abstract: A swimming fin comprising a blade extending from a shoe open at its rear side, and a rear heel strap connected to the sides of the shoe by at least one buckle, the buckle having a base plate integral with the shoe. A buckle arm is joined with the strap so as to allow adjustment of the strap's tension, an intermediate lever being connected pivotally to the base plate and the arm. A reversible attachment member is also provided for connecting the intermediate lever to the base plate to achieve closure of the buckle. Between the intermediate lever and the base plate, a disengageable articulation member is provided for reciprocal engagement between them, a pivotal connection, and, at the same time, for allowing their separation in a direction opposite to that of tensioning the strap. In this manner, the intermediate lever may be separated from the base plate following release of the attachment member, and disconnection of the disengageable articulation member.

Abstract: A swimming fin comprising a blade extending from a shoe open at its rear side, and a rear heel strap connected to the sides of the shoe by at least one buckle, the buckle having a base plate integral with the shoe. A buckle arm is joined with connected to the strap so as to allow adjustment of the strap's tension, an intermediate lever being connected pivotally to the base plate and the arm. A reversible attachment member is also provided for connecting the intermediate lever to the base plate to achieve closure of the buckle. Between the intermediate lever and the base plate, a disengageable articulation member is provided for reciprocal engagement between them, a pivotal connection, and, at the same time, for allowing their separation in a direction opposite that of tensioning the strap. In this manner, the intermediate lever may be separated from the base plate following release of the attachment member, and disconnection of the disengageable articulation member.

Abstract: A fin assembly for attachment to the foot covering of a float tube user is disclosed, the foot covering having a sole, a toe portion and a heel portion. The assembly includes a base member having a front portion, a rear portion, an upper surface and a lower surface. A mechanism is provided for releasably attaching the upper surface of the base member to the sole of the foot covering. A fin member is provided and has a front end portion, a rear end portion, a top surface and a bottom surface. A hinge apparatus mounts the front end portion of the fin member to the front portion of the base member so that the fin member is pivotally movable between a retracted position wherein the fin member top surface is positioned proximate the base member lower surface, and a base operational position wherein the fin member rear end portion projects at an angle below the base member lower surface.

Abstract: A swimming auxiliary device 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 web member to the attaching member. A pulling device is connected between the web member and the attaching member to pull the web member toward the attaching member. When the swimmer pushes the water, the water flows between the web and the attaching member so that the web member is pivoted away from the by the water. The web member is then pulled by the pulling device to return its original position again when the water flows away from the web member.

Abstract: Disclosed is a diving fin, securable about a swimmer's ankle, having a blade oriented at a propulsive angle independent of how the swimmer's toes are positioned. The blade can be positioned not to interfere with walking and wading. The blade and boot are lockably engageable, and are then rotatable to a locked deployed position wherein the blade projects past the swimmer's heel and in line with the swimmer's lower leg. In one embodiment, the blade has a connector and the boot has a hub lockably engageable therewith to attach or detach the blade. Thus, the boot can be worn without the blade. The engaged connector is upwardly rotatable behind the swimmer's leg. A strap secures the undeployed blade adjacent the leg. The connector is rotatable between the undeployed and deployed positions and is lockable in the deployed position. In one embodiment, the blade can wobble a few degrees when in the locked position.

Abstract: Fin according to the invention, with a seat (4, 22, 43) into which the foot may be introduced and wherein the walls (5, 8, 25, 41) of the seat grasp the foot at least partially, leaving out at least one area of the heel and of the ankle. The action of taking off and wearing the fin is made easier by providing that the fin (1, 21, 42), after the introduction of the foot into the seat (4, 22, 43) is automatically held back on the foot and removably connected thereto. There is also provided a combination of a fin of the aforesaid type with a type of footwear, like a boot (2), a shoe, or similar. In this case, the easier wear is due to the fact that the fin (1, 21, 42) is automatically held back on the footwear, being removably connected thereto.

Abstract: A retractable fin assembly is disclosed for attachment to the boot of a float tube user. The assembly includes a fin member movable between a fast position projecting below the boot adapted for propelling the float tube user forwardly in the water and a second position adapted for retraction relative to the heel of the boot to permit walking on land by the float tube user. Propulsion vanes are carried by the fin member and have a closed position for providing substantial resistance to the flow of water as the fin member is moved in rearward direction relative to the user. The vanes also have an open position for providing substantially reduced resistance to the flow of water as the fin member is moved in forward direction relative to the user. Finally, a mechanism is provided for attaching the fin member to the boot of a user so that the fin member first position aligns the propulsion vanes at a pre-selected angle of approximately 90.degree.

Abstract: A swim fin is disclosed that comprises a boot portion to receive the foot of a swimmer, a web portion, and a pair of side members. Each of the side members have 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 web 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 web portion to rotate about the boot portion such that when the leg engaging strap is attached to the lower leg of a swimmer the web portion is pivoted to a position approximately parallel to the swimmer's lower leg.

Abstract: A fin assembly is disclosed for attachment to a boot of a float tube user, the boot having a sole, a toe and a heel. The assembly includes a base member having a mechanism for attachment to a boot. The base member has a front portion for attachment proximate the toe of the boot and a rear portion for attachment proximate the heel of the boot. A fin member is provided with front and rear ends. A mechanism is provided for pivotally mounting the front end of the fin member to the front portion of the base member.

Abstract: Improved swimming efficiency and safety in a water environment is achieved with the use of retractable swim fins having a web-like member rotatably interconnected to a shoe-like member. A latch includes a latch element which secures the web-like member to the shoe-like member in a downward swimming position. The latch element is released by linear pressure from the other foot to permit the web-like member to rotate in response to a spring force to an upward walking position. A natural swimming kick returns and latches the web-like member to the swimming position.

Abstract: Improved swimming efficiency and safety in a water environment is achieved with the use of retractable swim fins having a web-like member rotatably interconnected to a shoe-like member. Latching means secure the web-like member to the shoe-like member in a downward swimming position. Releasing means permit the web-like member to rotate to an upward walking position. Pressure from a swimmer's foot returns and latches the web-like member to the downward position.

Abstract: A swim fin includes harness for attachment to a wearer's foot, the harness including an adjustable strap secured to the fin on opposite sides of a forward portion of the wearer's foot, the adjustable strap forming an X configuration passing over the wearer's instep and around the wearer's heel. Liner straps are arranged between forward portions of the adjustable strap and the wearer's foot while lateral straps are anchored to rearward portions of the fine and secured to opposite side portions of the adjustable strap. The fin has a generally flat configuration with one or more flanges extended beneath the wearer's foot and along forward portions of the fin for controlling the amount of bending or flexing experienced by the fin.

Abstract: Harness for securing a swim fin beneath a wearer's foot is disclosed including two strap portions having respective front and rear anchor points on opposite sides of the fin relative to the wearer's foot, the strap portions forming an X configuration and being sufficiently long to pass over the wearer's instep, an adjustable heel strap being secured to the respective strap portions forward of their rear anchor points and of a sufficient length for adjustable engagement behind and above the wearer's heel.

Abstract: The improvement provided by this invention is directed at the conventional beach-shoe and diving flipper, and according to this invention, a novel beach-shoe capable of acting as a diving flipper is provided. The web portion is extensible relative to a shoe body, the shoe can be used as a beach-shoe when a web member is received in a recess of the shoe body, and a guarding piece is placed in a cut-out made in the front end of the shoe body to admit the web member to pass through.