Abstract: The present invention provides an angle changeable apparatus and an oar such that the shaft angle is easily adjustable. Disclosed is an angle changeable apparatus 1 for variably changing an angle of a shaft 110 inserted in a sleeve 10, including: a shaft-side member 20 fixed to the shaft 110; a sleeve-side member 30 fixed to the sleeve 10; and a slider 40 configured to slide between the shaft-side member 20 and the sleeve-side member 30, wherein the shaft-side member 20 has a first guiding part extending in a shaft direction, the sleeve-side member 30 has an elongated hole 31 extending in an oblique direction relative to the shaft direction, the slider 40 has a groove 41c guided by the first guiding part and a slider main body 41 guided by the elongated hole 31.

Abstract: A Cantilever Beam Linkage is disclosed for a mechanism and structural support to power and control a cantilever beam in reciprocal motions, by adopting and using planar 4-bar parallelogram linkages, typically for drive mechanisms, into mechanisms to function as guided roller supports, free to translate but fixed for rotational motions; and as load separators where forces and moments are separated. A Cantilever Beam Linkage is applicable for a cantilever beam in reciprocal motions to have its powering and controlling applied forces confined within narrow bodies, to have the cantilever beam extends out multiple times the narrow body width, and to have applied forces equal to response forces; and is particularly suitable for applications such as: a rowing boat oar and a flying machine flapping wing.

Abstract: A standup forward facing rowing watercraft is disclosed. The craft includes a hull having first and second opposed ends; a deck affixed to the hull, the deck including a surface for supporting a rider who may face in the direction of the movement of the watercraft; and an outrigger attached to the deck, the outrigger including a pivot point that extends outwardly from the deck, the pivot point being capable of accepting an oar. The oar is capable of rotating in the pivot point so as to allow a rider to employ a j-stroke to provide forward course correction when powering the watercraft with one oar. The outrigger can be adapted to include a second pivot point extending outwardly from the deck, the second pivot point being capable of accepting a second oar. The outrigger may preferably be adapted for longitudinal movement in relation to the deck of the watercraft.

Abstract: A propulsion mechanism to propel a watercraft through water comprises paddle bars pivotally attached to a support at a first pivot, the paddle bars having a handle at a first end and a paddled second end. A paddle is pivotally attached to the second end of each paddle bar at a second pivot. When the mechanism is operated through the power stroke, the second pivot end allows the paddle to be supported by the respective paddle bar and to be forcefully driven through the water. When the power stroke is completed, the paddle is permitted to pivot about the second pivot and to disengage the respective paddle bar as the mechanism operates through the return stroke.

Abstract: A paddle assembly includes a tubular shaft that is configured to be coupled to a blade of the paddle assembly. The shaft has a shaft length, a first flexural rigidity at a first location along the shaft length and a second flexural rigidity at a second location along the shaft length. The ratio of the first flexural rigidity to the second flexural rigidity can be at least approximately 1.20. The shaft is substantially linear along the shaft length. The shaft has a shaft midpoint. The first location and the second location are substantially equidistant from and on opposite sides of the shaft midpoint. The shaft can have a tubular configuration. The shaft has a plurality of layers of material at each of the first location and the second location. The orientation of the layers of material at the first location is different than the orientation of materials at the second location. A modulus of elasticity of the materials used to form the shaft varies along the shaft length.

Abstract: The present invention relates to a watersport paddle blade comprising a throat configured to attach to a shaft, a power face attached to the throat, wherein the power face comprises a main channel beginning at or near the throat, extending along the center of the face and opening at a distal end of the blade, and a plurality of side channels connected to the center channel, wherein the side channels are slanted and extend from the lateral edge inwardly toward the center channel and are angled downwardly toward the distal end of the blade.

Abstract: An apparatus for floatation and propulsion of a user on a body of water includes a floatation device, a harness and a pair of paddles. The harness attaches to the user's torso and the paddles have upper ends that pivotally interconnect with the harness. The paddles have lower water engaging ends that may be moved in a paddling motion in a generally fore-aft direction relative to the harness.

Abstract: A paddle device. First and second paddle assemblies each have a paddle blade extending from a paddle end of a paddle arm so that the paddle structures each have a paddle blade end and a paddle arm end. A hand crankable crank shaft arrangement have a center and first and second ends and having handle segments. The paddle arm end of the first paddle structure is coupled to the first end of the crank shaft arrangement and the paddle arm end of the second paddle structure is coupled to the second end of the crank shaft arrangement. First and second handle grips are rotatably coupled to the crank shaft arrangement so as to permit the crank shaft arrangement to rotate with respect to the first and second handle grips when the crankshaft arrangement is cranked. This abstract is not to be considered limiting.

Abstract: A multi-functional modular device includes: a shaft; electric motor(s); propeller(s); battery(s); and paddle blade(s) being removably attachable to the shaft for levering of a boat. With the blade(s) attached to the shaft and motor(s) de-energized, the device is usable for manual levering, and with the motor(s) energized, propeller thrust selectively assists in levering to propel the boat. Propeller thrust in a direction opposite to a propulsive direction from levering reduces work required per stroke, reducing the total levering power per stroke. Alternatively, using the thrust in the same direction as propulsive levering increases total propulsive power per stroke, but requires greater strength/work output by the rower/paddler. Removing the blade permits the propeller and motor to be statically submerged and clocked for directional propulsion.

Abstract: An oar includes a retractable shaft with a blade and a grip connected to two ends thereof. A socket is connected to the shaft by a pin and includes a first toothed surface on the end surface of the socket. The grip includes a tubular portion which is mounted to the socket. A spring and a bolt are located in the socket, and the bolt is securely connected with the grip so that the spring is biased between the grip and the head of the bolt. The tubular portion of the grip includes a second toothed surface in an inner end thereof so as to be removably engaged with the first toothed surface of the socket.

Abstract: A paddle suitable for use with a kayak or like watercraft, the paddle comprising: (a) a tubular shaft extending from a first blade located at a first end to a second blade located at a second end; (b) a sleeve mounted on the tubular shaft, the sleeve having an outer surface; and (c) a lever extending along a curvature from a proximal end to a distal end, the proximal end being pivotably mounted to the sleeve, the lever comprising a lengthwise extending chamber having an opening provided on an upper wall of the lever and a closed end located remote from the opening and wherein the chamber communicates with a passage extending towards an entry located at the distal end, the lever being movable between a first position, wherein the lever is located proximate the outer surface of the sleeve, and a second position, wherein the distal end of the lever is accessible by the mouth of a user for allowing the user to blow in the entry for generating an airstream within the passage and the chamber such that sound is prod

Abstract: A paddle suitable for use with a kayak or like watercraft, the paddle comprising: (a) a tubular shaft extending from a first blade located at a first end to a second blade located at a second end; (b) a sleeve mounted on the tubular shaft, the sleeve having an outer surface; and (c) a lever extending along a curvature from a proximal end to a distal end, the proximal end being pivotably mounted to the sleeve, the lever comprising a lengthwise extending chamber having an opening provided on an upper wall of the lever and a closed end located remote from the opening and wherein the chamber communicates with a passage extending towards an entry located at the distal end, the lever being movable between a first position, wherein the lever is located proximate the outer surface of the sleeve, and a second position, wherein the distal end of the lever is accessible by the mouth of a user for allowing the user to blow in the entry for generating an airstream within the passage and the chamber such that sound is prod

Abstract: A paddle for use in watersports is provided with shaft halves and blades at the end of each shaft half with a selectable offset angle between the blades. A joint connecting the shaft halves may include an interlocking coupling and a biasing member. The interlocking coupling maintains, in a use configuration, the offset angle of the blades, and allows, in a selection configuration, a change in the offset angle of the blades. The biasing member typically holds the interlocking coupling in the use configuration, and the shaft halves may be moved axially apart for the selection configuration. All mechanisms for switching the interlocking coupling between the use configuration and the selection configuration are normally located within the shaft halves. A retaining clip may be coupled between the first and second shaft halves to allow the selection configuration while preventing disassembly of the first and second shaft halves.

Abstract: A rowing oar handle comprising a first portion and a second portion, in which the first portion and the second portion are axially rotatable to one another, and in which in use the point of rotation is located between a user's hands.

Abstract: A watercraft (1) includes at least two oar handles (3a, 3b) which are designated to be actuated by a passenger of the watercraft in order to propel the same. A considerably expanded functionality is achieved in such a way that the oar handles (3a, 3b) are connected to a control unit which controls at least one power-actuated driving motor (6a, 6b; 7; 16a, 16b; 26a, 26b) of the watercraft depending on the actuation of the oar handles (3a, 3b).

Abstract: A paddle stick for propulsion of a recreational water craft utilizing the arms in an athletic sequence similar to that of cross country skiing, the paddle stick formed of a shaft having an upper handle end and a lower end having a flotation device secured thereabout, the shaft member further extending below the flotation device in a threaded configuration for receipt on the threaded shaft of a biasing means in the form of a coil spring and a threaded stopper cap superimposed over the biasing means to adjust the tension thereon, the lower end of the shaft in pivoting relationship with a paddle shaft angularly displaceable with respect to said handle shaft about said pivot point, said paddle shaft having a plurality of radially outwardly extending paddle blades freely rotatable on the paddle shaft.

Abstract: An improved oar that has an oarlock assembly, which holds the main oar shaft and parallel link in line with each other while allowing them to pivot fore and aft and up and down; an oar shaft; a parallel link; and a knuckle. The knuckle positions the handle via a sleeve, and the parallel link that is positioned by a pivot on the end of an arm. Additionally, there is a universal joint between the oar shaft and the handle, in line with the parallel link pivot, that allows the blade to be feathered while keeping the handle perpendicular to the rowing shell at every point in the stroke.

Abstract: A frame assembly forming a portion of a rowing accessory is to be mounted within a watercraft, to which frame assembly is attached a seat and oars. The frame assembly comprises first and second frame members each having the general shape of a winged U. First and second wing portions of each frame member extend outwardly from upper ends of the frame members. A track assembly has a beam attached to lower portions of the frame members at spaced apart connection points along the length of the beam. A seat assembly attaches to and slides along the beam. First and second hinge plates each have a first end attached at an outboard end of one wing portion of the first frame member, and a second end attached at an outboard end of one wing portion of the second frame member.

Abstract: A stability adjustable unit for a seat of an exercise device that is configured for movement on the device may include a sub-assembly connected between the seat and a roller assembly of the device on which the seat rests. The unit may include a selector provided on the sub-assembly and operable by a user seated on the seat to vary a degree of stability of the seat.

Abstract: A rowing oar handle comprising a first portion and a second portion, in which the first portion and the second portion are axially rotatable to one another, and in which in use the point of rotation is located between a user's hands.

Abstract: A coupling apparatus for adjusting and axially coupling first and second shafts about a feathering axis, comprising a collar having an end face having a plurality of axial notches, an insert having an extended portion and at least one radial pin and a cam ring circumscribing the collar. The collar is securable to a free end of a first. The insert is securable in a free end of a second shaft such that the extended portion extends axially from the second shaft and are receivable in the free end of the first shaft such that the pins engage upon the notches so as to axially couple the first and second shafts. The cam ring includes a plurality of radial flange segments and is rotatable to engage the pins so as to retain the pins in engagement with the notches.

Abstract: A device for propelling a personal watercraft comprising a base having an inner channel and an outer channel. A fin is disposed substantially adjacent to the base and is rotatable relative to the base. The fin has an inner protrusion adapted to moveably engage the inner channel, and an outer protrusion adapted to moveably engage the outer channel. A yoke is disposed substantially adjacent to base and adapted to engage the inner protrusion. When a force is applied to the yoke along a first vector, the inner and outer protrusions move in reciprocal directions causing the fin to rotate.

Abstract: An object is to provide a Ro-scull which can suppress a decrease in thrust force by water resistance generated during turn-over operation and can realize high-speed cruise of a boat. The Ro-scull has a Ro-arm 1 and a Ro-blade 2 having a flat part 12 perpendicular to the Ro-arm 1. The Ro-arm 1 is attached to an upper end portion of the Ro-blade 2 from an obliquely lower side. Namely, the Ro-arm 1 and the Ro-blade 2 are joined to each other while the Ro-arm 1 “receives” the Ro-blade 2. A Ro-handle 3 is arranged not on the upper surface side but on the lower surface side of the Ro-arm 1.

Abstract: An oar consisting of two parallel shafts linked on both ends to form a parallelogram configuration, which keeps the oar's blade and handle parallel to one another and perpendicular to the boat throughout the rowing cycle. The system is further enhanced to provide an internal, adjustable feathering system, interchangeable handles and blades and an integrated, quick-release oarlock.

Abstract: A new and improved leg assisted forward facing rowing system is disclosed wherein a rower applies leg power to propel a boat by means of a rope connected between his or her foot and an oar. A unique feature is a roller, fastened under the heel of the rower's foot, that rolls along the bottom of the boat supporting the weight of the rower's leg while the reciprocating motion of the leg is transmitted by rope going through pulleys to reverse the force applied to the oar. The oar is pivoted at the center of the boat above the rower's knees by a mechanism that includes provision for applying lifting force to support the oar weight thereby holding the oar blade out of the water when no force is applied. The rower's legs, back and arms simultaneously apply rowing force. Feathering at the end of a stroke and squaring action at the beginning are provided by wrist action to rotate the oar blade.

Abstract: The present invention provides a coupler for rotationally and/or axially securing two shafts together while permitting rapid angular adjustment between the shafts. The coupler includes a first component mountable to a first section of the paddle and a second component mountable to a second section of the paddle. The first component includes a receptacle, and the second component includes a protrusion operable to extend into the receptacle to position the first component relative to the second component and to prevent the first component from turning relative to the second component. To turn and reposition one of the components relative to the other component, the second component is axially movable relative to the first component. The coupler may also include a retainer to prevent the first component from inadvertently being repositioned relative to the second component.

Abstract: A rowing apparatus is provided for connection to a vessel and includes an oar direction-of-motion reversal assembly, fulcrum stabilizing means connected to the oar direction-of-motion reversal assembly, and vessel-to-oar-apparatus connection means connected to the fulcrum stabilizing means for connecting the apparatus to the vessel. Preferably, the oar direction-of-motion reversal assembly includes an oar handle portion, an oar blade portion, and a casement assembly for supporting the oar handle portion and the oar blade portion. A pair of oar direction-of-motion reversal assemblies are provided which provide a pair of oar handle portions and a pair of oar blade portions. The apparatus provides that a rower faces in the direction that the vessel is propelled when the rower pulls on the oar handle portions.

Abstract: In shells with two, four or eight rowers, a method of rowing is proposed to reduce the stroke cycle velocity variation from that obtained when two, four or eight rowers row in unison. To reduce the stroke cycle velocity variation and to thereby obtain a greater average velocity for the same power input, we propose that individuals or groups of individuals row out of phase with other individuals or groups of individuals comprising the crew of a boat. We refer to this method of rowing as stroke cycle phase shift rowing. In boats with unison rowing, the rowers are evenly spaced with about 1.4 m separating adjacent rowers. To facilitate stroke cycle phase shift rowing, individuals or groups of individuals in a crew are spaced further apart than the spacing for adjacent rowers rowing in unison.

Abstract: A rowing apparatus is provided for connection to a vessel and includes an oar direction-of-motion reversal assembly, fulcrum stabilizing means connected to the oar direction-of-motion reversal assembly, and vessel-to-oar-apparatus connection means connected to the fulcrum stabilizing means for connecting the apparatus to the vessel. Preferably, the oar direction-of-motion reversal assembly includes an oar handle portion, an oar blade portion, and a casement assembly for supporting the oar handle portion and the oar blade portion. A pair of oar direction-of-motion reversal assemblies are provided which provide a pair of oar handle portions and a pair of oar blade portions. The apparatus provides that a rower faces in the direction that the vessel is propelled when the rower pulls on the oar handle portions.

Abstract: A breakdown oar for manually propelling a watercraft manufactured of at least two sections that may be easily joined or separated and the fastener set between the two parts. The sectional nature of the oar allows disassembly or breakdown for transportation or stowage of the oar in a space shorter than the overall length of the oar. The sections may be made of aluminum to reduce weight and provide an overall stronger oar. The reduced weight oar is easier to use following the easy assembly.

Abstract: An oar handle is used in sweep rowing. Sweep rowing is when a single oar is pulled by both hands of a single rower. The oar handle has a support which at one end can be secured to the end of the shaft of a sweep rowing oar. A handle bar having a pair of hand grips at its opposite ends is mounted at its center to the opposite end of the support. The handle bar is mounted to the support so that it is free to rotate on the support about a pivot point in the center of the handle bar. The pivot point is aligned with the central axis of the support. When the oar handle is mounted on the shaft of an oar with its central axis in alignment with the central axis of the oar, the pivot point is likewise aligned with the central axis of the oar. In use, a rower grips each one of the hand grips with one of his hands. As the rower pulls the oar, the handle bar rotates relative to the central axis of the oar, allowing the rower to pull equally with both of his arms and his body.

Abstract: The watercraft has an elongated hollow hull having a pair of integral outwardly and upwardly projecting outrigger wings, onto which are mounted oar mounting devices each having a flat casing attached to rods protruding out of the outrigger wings. The attachment of the casing to the rods is accomplished with sockets installed on the rods, which have spherical housings engaged by ball joint portions provided on the casing, to form a ball and socket joint. The sockets are longitudinally spaced-apart on the hull side edge portion, so as to allow the casing to swivel about an axis parallel to the watercraft longitudinal axis. The casing is engaged by a pair of oar members pivoted therein in the plane of the flat casing. A pair of wires interconnect the pivoted oar members inside the casing, to allow pivotal displacement of the oar members only in opposite directions.

Abstract: A rowing apparatus which allows an oarsman to face forward while propelling a watercraft such as a canoe (20) forward when pulling on handles (32). The articulated apparatus includes two sheaves coupled by a pair of criss-crossing, adjustable cables enclosed within a housing (24). A detachable, obtuse-angle shaped handle (32) attaches to a handle lever (34), which attaches to an upper side of one of the sheaves. An under side of the other sheave attaches to an oar blade lever (38), which extends to an oar blade (40). Each sheave has an axle (120) supported at its extremities by housing (24) and a canopy (26). A canopy cover (28) encloses each canopy (26), fastens to each axle (120), and rotates with its respective lever (34) or (38). A pair of outriggers (30A) and (30B) pivotally support housing (24) at an outboard location and attach to a pair of thwarts (46) and (48). A pair of webbing straps (50) form an "X" brace between thwarts (46) and (48).

Abstract: A canoe attachment includes a frame made of cylindrical members arranged in a substantially rectangular configuration. A seat is suspend between the forward frame member and the rearward frame member. A "forward-facing" rowing assembly is rotatably mounted on each of the opposite side frame members.

Abstract: An apparatus for use in forward facing rowing of a boat having oars mounted ahead of the oarsman and having a seat fixedly secured in the boat is disclosed. The apparatus comprises an inboard support assembly and an outboard support assembly. The outboard support assembly is connected to boat oars for pivotal movement of the oars with respect to the outboard support assembly in at least horizontal and vertical planes, and also allows rotational movement of the oars with respect to the outboard support assembly. The inboard support assembly is comprised of a mounting bracket slidably secured within the boat, as well as a first elongate support and a second elongate support, both of which are pivotally attached to the mounting bracket for horizontal movement of the first elongate support and the second elongate support.

Abstract: An oar mounting system for forward-facing rowing in which an arm or pulley strut is hinged to a support or gunwale frame, with an end of the arm extending from the frame and rotationally mounting an auxiliary or inner oar frame to which an oar loom is attached and the auxiliary frame is tensioned with respect to the arm. The tensioning is by a cable that extends from a terminal post on the auxiliary frame around a pulley at the end of the arm and around a further pulley hinged to the support frame.

Abstract: A front-facing rowing arrangement for a boat includes a pair of oars of which includes a handle 1 and a blade 3 mounted for pivotal movement about spaced parallel axes on a supporting member 5 which is itself hingedly mounted for movement about a horizontal axis extending parallel to the direction of travel of the boat. The handle 1 and blade 3 of each oar are connected by a lever/linkage system which is such that the angular velocity of the blade relative to the angular velocity of the handle increases steadily throughout a typical power stroke.

Abstract: An oar includes a blade portion, a loom including a grip, and a connecting member for connecting the blade portion and the loom together. The blade portion includes a frame and two blades. The frame includes two parallel vertical plates, a front plate, a top plate, a bottom plate and an open rear side defined by the vertical plates, the top plate and the bottom plate. A rectangular slot is formed between each blade and the front plate. A protrusion is formed on a top edge and a bottom edge of each blade. The blades are pivotally restrained in the rectangular slots with the protrusions engaging with corresponding holes formed on the top plate and bottom plate of the frame.

Abstract: A forward facing rowing mechanism (10) for a boat (11) having a bow (12), a longitudinal axis (A.sub.1) and both port and starboard gunwales (21). A mounting bracket (20) is adapted to be supported from each gunwale (21), and a tilting frame (25) is supported from the mounting bracket (20) for pivotal movement about an axis (A.sub.2) substantially parallel to the longitudinal axis (A.sub.1) of the boat (11). A drive sub-assembly (31.sub.x) is carried on the tilting frame (25) to be pivotal about a first angular rotational axis (A.sub.3). A driven sub-assembly (31.sub.y) is carried on the tilting frame (25) to be pivotal about a second angular rotational axis (A.sub.4). A handle (14) is secured to the drive sub-assembly (31.sub.x) for rotation about a first feathering axis (A.sub.5). A blade (18) is secured to the driven sub-assembly (31.sub.y) for rotation about a second feathering axis (A.sub.6). A first drive (83 and 84) interconnects the drive and driven sub-assemblies (31.sub.x and 31.sub.

Abstract: An oar and oarlock arrangement comprising, in combination: a handle loom and a structurally separate blade loom having a hydrofoil blade mounted to its outermost end, the handle loom and blade loom being hinged for sweep action about a rockable oarlock. The handle and blade looms are interconnected by a motion reversing linkage such as a pair of gears, for example. A feathering linkage is provided between the main frame of the oarlock and the hydrofoil blade for changing the angle of attack of the blade in the water.

Abstract: A bow facing rowing system comprising the combination of an oar reversing device and a bracket device for supporting the oar reversing device. The oar reversing device includes a housing having opposing ends which terminate in a pair of upper and lower flanges defining fixed spaces therebetween. A train of gears is disposed essentially within the housing with one end gear of the train of gears forming a first terminal gear having an integral extension passing through the adjacent fixed space and terminating in an oar member and the opposite end gear of the train of gears forming a second terminal gear having an integral extension passing through the adjacent fixed space and terminating in a handle member. The gears intermesh in the same plane to thereby transmit motion in reverse from the handle member to the oar member.

Abstract: A double-bladed kayak paddle (A, B) is disclosed which includes first and second blade sections (10, 12) having a paddle blade (14, 18) carried on one end thereof, and jointed ends (16, 20) carried on opposing ends thereof. The jointed ends are fitted together to form a joint (C) which effectively prevents torque forces from being placed on a latch mechanism (D). The latch mechanism includes a latch button (24) carried within a hollow sleeve (22) which interfits within hollow portions of the first and second blade sections (10, 12). Latch openings (32, 34 and 60, 62) are circumferentially spaced around the first section (10) to provide a number of operational positions for different operational blade configurations. Various right and left hand control configurations are provided for the paddle, as well as feathered and nonfeathered configurations.