Patent Publication Number: US-6709306-B2

Title: Aquatic propulsion device

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation-in-part of U.S. patent application Ser. No. 09/709,186, filed Nov. 8, 2000, and claims priority thereto. 
    
    
     FIELD OF INVENTION 
     This invention relates to human powered devices for enhancing propulsion in, through, or upon water. 
     BACKGROUND 
     Human powered aquatic propulsion devices are often used for purposes of sport, recreation, exercise, training, rescue, and/or rehabilitation. Aquatic propulsion devices exist in different configurations, some of which rely primarily upon lower body strength and others that primarily rely upon upper body strength. Aquatic propulsion devices that rely upon upper body strength frequently utilize hand paddles as a propulsion enhancement mechanism. Examples of aquatic propulsion devices utilizing hand paddles are given in U.S. Pat. Nos. 3,913,907; 3,922,740; 5,658,224; 5,288,254, and 4,913,418. Some aquatic propulsion devices utilize paddles or fins attached to a forearm, such as those described in U.S. Pat. Nos. 4,521,011 and 3,786,526. 
     Hand paddles enhance aquatic propulsion by displacing a greater amount of water for a given movement than would result from hand movement alone. Aquatic propulsion may also be enhanced through the leveraging of force over a distance greater than that defined by a human limb movement alone. As an example, the use of oars for rowing boats leverages force over distance, thereby increasing the efficiency of human work. Unfortunately, the hand and/or forearm paddles mentioned above fail to incorporate useful leveraging action. Such hand and/or forearm paddles may be characterized as providing a water displacement distance that is the same as or less than the movement of a hand, thereby undesirably limiting the extent to which they may enhance aquatic propulsion. 
     A hand paddle disclosed in U.S. Pat. No. 4,509,744 extends a center of displacement slightly beyond a hand, directly away from an arm. However, this invention is designed only as an exercise device to be utilized against the resistance of water. Due to design shortcomings, this and similar types of inventions would be of limited use relative to enhancing aquatic propulsion. 
     The torque generated by water resistance at the center of displacement and the force applied by a hand increase linearly with the distance between the center of displacement and the hand. This force must be countered by an equal but opposite force to keep a paddle substantially in plane with the hand and arm. 
     U.S. Pat. No. 4,509,744 discloses a hand paddle that uses a wrist guide, which reduces the turning moment about a user&#39;s wrist. Because of the proximity of the wrist to the hand relative to the distance from the hand to the center of water displacement, leveraged forces can become very great at the wrist. A wrist is typically bony and uneven on its top side, while its underside is soft, having many unprotected moving tendons. Thus, the wrist is not suitable for countering torque generated by an extended center of water displacement. The hand paddle design disclosed in U.S. Pat. No. 4,509,744 is therefore problematic relative to the stresses imposed upon a user&#39;s wrist. 
     A paddle may be defined as having a leading edge, which is the edge that first ‘cuts’ though the water on the return or non-power stroke during swimming. As the perpendicular distance of a paddle&#39;s leading edge relative to a hand or arm increases, the paddle&#39;s steering radius undesirably increases, and a user&#39;s margin for error and ability to perform directional adjustments decrease. This effect is similar to using the rear wheels of a car for steering. Unfortunately, prior hand and arm paddles fail to properly position the leading edge of the paddle relative to a user&#39;s arm or hand, thereby limiting their ease of use and effectiveness. 
     In addition to the aforementioned problems, the enhanced water displacement of hand and arm paddles can be disadvantageous or dangerous when hands and arms need to be used for actions other than swimming, for example, when taking pictures, picking up objects, or adjusting scuba or snorkeling apparatus. Removal of prior art hand and/or arm paddle assemblies can be problematic since such assemblies encumber both hands and arms. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a drawing illustrating a diver using an aquatic propulsion device constructed in accordance with the present invention. 
     FIG. 2 is a perspective view showing a user&#39;s arm position while holding an aquatic propulsion device constructed in accordance with the present invention. 
     FIG. 3 is a perspective view of an aquatic propulsion device constructed in accordance with the present invention. 
     FIG. 4 is an exploded perspective view of an aquatic propulsion device constructed in accordance with the present invention. 
     FIG. 5 is a side view of an aquatic propulsion device folded into a storage position. 
     FIG. 6 is a side view showing structural elements that facilitate the folded storage position of FIG.  5 . 
     FIG. 7 is a perspective view showing exemplary first, second, and third paddle flex patterns. 
     FIGS. 8A,  8 B, and  8 C are side views respectively showing a first, a second, and a third exemplary rotational orientation of the aquatic propulsion device relative to a user&#39;s arm rotation. 
     FIG. 9 is a perspective view of a first alternate embodiment of an aquatic propulsion device constructed in accordance with the present invention. 
     FIG. 10 is a perspective view of a second alternate embodiment of an aquatic propulsion device constructed in accordance with the present invention. 
     FIG. 11 is a perspective view showing structural elements that facilitate a disengaged position for the aquatic propulsion device of FIG.  10 . 
     FIG. 12 is a perspective view showing a third alternate embodiment of an aquatic propulsion device constructed in accordance with the present invention. 
     FIG. 13 is a perspective view showing a fourth alternate embodiment of an aquatic propulsion device constructed in accordance with the present invention. 
     FIGS. 14A and 14B are a side and perspective view respectively showing a fifth alternate embodiment of an aquatic propulsion device with a curved forearm support constructed in accordance with the present invention. 
     FIGS. 15A and 15B are end views exemplifying a curved profile of a forearm support for the aquatic propulsion device of FIGS. 14A,  14 B and  14 C. 
     FIGS. 16A and 16B show an exploded perspective view respectively showing structural elements for the aquatic propulsion device of FIGS. 14A,  14 B,  14 C and  15 A. 
     FIGS. 17A,  17 B and  17 C are a side and perspective views showing a sixth alternate embodiment of an aquatic propulsion device with a forearm member mount and an elongated member positioned in alternate orientations relative to a forearm constructed in accordance with the present invention. 
     FIG. 18 is a perspective view showing structural elements that facilitate adjustment of a forearm support width of the aquatic propulsion device of FIGS. 17A and 17B. 
     FIGS. 19A and 19B are frontal views showing a motion and flexural pattern of an aquatic propulsion device in accordance with a method of usage of the present invention. 
     FIGS. 20A and 20B are frontal views showing a motion and flexural pattern of an aquatic propulsion device in accordance with an alternate method of usage of the present invention. 
     FIGS. 21A,  21 B and  21 C are a side extended, a side folded and a perspective exploded view respectively showing a seventh alternate embodiment of an aquatic propulsion device constructed in accordance with the present invention. 
     FIG. 22 is a perspective view showing an eighth alternate embodiment of an aquatic propulsion device constructed in accordance with the present invention. 
     FIG. 23 is a perspective view showing a ninth alternate embodiment of an aquatic propulsion device constructed in accordance with the present invention. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 of the accompanying drawings illustrates a person  30  using an aquatic propulsion device  32  according to an embodiment of the invention. The aquatic propulsion device  32  comprises a paddle  34 , a hand grip  36 , a forearm member mount  38 , an elongated forearm member  40 , and a forearm support  42 . In use, the person  30  inserts an arm  52  into the forearm support  42 , and uses a hand  54  to hold or grasp the hand grip  36 . The person  30  alternately employs or performs propulsive, or power, strokes, followed by return, or non-power, strokes with the present invention to propel themselves through water. 
     Relative to propulsive strokes, movement of the arm  52  and hand  54  along the general direction of a propulsive axis, arc, or travel path  60  applies a force to the hand grip  36 . This force in turn causes the paddle  34 , which is oriented or held generally perpendicular to the propulsive axis  60  during the propulsive stroke, to displace a significant amount of water along the direction of the axis  60 , thereby propelling the person  30  forward. The person  30  may adjust the particular orientation of the axis  60  by rotating their arm  52  and hand  54 , which in turn may adjust the direction of propulsion during use. 
     Relative to return strokes, movement of the arm  52  and hand  54  along a return path (not shown) such that the paddle  34  is held or oriented generally parallel to the return path to minimize the amount of water displaced by the aquatic propulsion device  32  effectively returns the aquatic propulsion device  32  to a position from which another power stroke may originate. Those skilled in the art will understand that a return stroke may generally retrace some or all of a power stroke, and that a return stroke may be used to reorient the aquatic propulsion device  32  to a new position prior to a power stroke. 
     Referring also now to FIG. 2, a perspective view shows an aquatic propulsion device  32  supporting a user&#39;s arm  52 . The forearm support  42  may be generally u-shaped, and includes a support bottom  44 , a support front  46 , a support back  48  and a support opening  50 . The support bottom  44  is secured to the elongated forearm member  40 , and the support front  46  and support back  48  are secured to the support bottom  44 . Depending upon particular embodiment details, the support front  46  and/or the support back  48  may form a single, integral unit with the support bottom  44 . The support opening  50  is formed by a space between the support bottom  44 , the support front  46  and the support back  48 . A person  30  using the present invention inserts a forearm  56  into the support opening  50 , such that the forearm  56  is positioned against or upon the support bottom  44 , the support front  46 , and the support back  48 . 
     Opposing ends of the hand grip  36  are secured to the paddle  34 . One end of the forearm member mount  38  is secured to the paddle  34 , and an opposing end of the forearm member mount  38  is secured to one end of the elongated forearm member  40 . In response to a person&#39;s hand  54  applying a force against the hand grip  36  along the axis  60 , water resists the movement of the paddle  34  and creates a resistive force  62 . The resistive force  62  may be effectively characterized by a resistive center  64 . Increasing the distance between the resistive center  64  and the hand grip  36  directly away from the arm  52  advantageously enhances aquatic propulsion by leveraging force over a distance or arc length greater than that defined by hand movement alone. As an analogy, the use of paddles for rowing canoes leverages force over distance, thereby increasing the efficiency of human work. The present invention&#39;s leveraging of force significantly enhances a user&#39;s propulsion through water relative to prior types of devices such as conventional hand paddles. 
     The resistive force  62  at the resistive center  64  generates a rotational moment  66  about the hand grip  36 . Those skilled in the art will understand that movement of the paddle  34  along or about the rotational moment  66  should generally be restricted or limited to maximize the amount of water the paddle  34  displaces. 
     Through the aforementioned leveraging action, the torque generated by the rotational moment  66  proximate the hand  54  may be quite significant, and thus the hand  54  alone may have difficulty countering the rotational moment  66 . The present invention addresses this situation via the forearm support  42 . In particular, the support back  48  provides a surface capable of bearing pressures applied by the forearm  56  to counter the rotational moment  66  around the hand grip  36 . The distance between the hand grip  36  and the forearm support  42  reduces the leveraging action of the rotational moment  66  proportional to the distance between the hand grip  36  and the resistive center  64 . Therefore, the force applied by the support back  48  against the forearm  56  is significantly reduced relative to a force that would otherwise be required proximate the hand  54  or wrist. Moreover, a person&#39;s forearm  56  tends to be muscular, and can therefore more easily and comfortably bear the force applied by the support back  48 . One skilled in the art will recognize that movement of the arm  52  and the hand  54  opposite to the axis  60  results in the generation of oppositely-directed forces that can be countered to the same effect and advantage by the forearm  56  against the support front  46  of the forearm support  42 . 
     At times, a person&#39;s arms  52  and hands  54  may be required for actions other than aquatic propulsion, for example, taking pictures, picking up objects, and/or adjusting scuba or snorkeling gear. In one embodiment, by simply releasing the hand grip  36 , the resistive effect of water and/or gravitational forces allow the user  30  to freely remove their arm  52  and hand  54  from the aquatic propulsion device  32 . The present invention may advantageously provide simple, rapid, and unaided removal of the arm  52  and hand  54  to maximize both safety and convenience. 
     Referring also now to FIG. 3, a perspective view shows additional details of an aquatic propulsion device  32  constructed in accordance with the present invention. The embodiment shown in FIG. 3 includes a tether  84 , which may be employed to prevent the aquatic propulsion device  32  from drifting, floating, sinking or otherwise undesirably moving away when the person  30  releases or disengages their hand  54  and arm  52  from the aquatic propulsion device  32 . The tether  84  may be added to or included in any particular embodiment of aquatic propulsion device  32 . In one embodiment, a first end of the tether  84  may be secured to the elongated forearm member  40  using a tether pin  86 . An opposing end of the tether  84  may be secured to an arm strap  88 . The arm strap  88  may be secured as desired along the arm  52  using, for example, a Velcro strap, a buckle, or other attachment mechanism as would be well understood by one skilled in the art. In another embodiment, the tether  84  and/or the aquatic propulsion device  32  itself may be secured to the person  30  at a swimming suit, a waist belt, a diving vest, a life vest or a wet/dry suit using a Velcro strap, a buckle, a clip, a carabiner or other type of conventional attachment mechanism. 
     FIG. 3 additionally shows that the paddle  34  includes a leading edge  70 ; a rigidifying support  72  having a trailing side  74 ; a resistive surface  76 ; a spacing hole  78 ; a spacing recess  80 ; and a hand grip hole or opening  82 . The rigidifying support  72  lies along or upon the paddle&#39;s leading edge  70 . The resistive surface  76  may be secured to the paddle  34  along the rigidifying support&#39;s trailing side  74 . Those of ordinary skill in the art will readily understand that the rigidifying support  72  and resistive surface  76  may be constructed in alternative shapes and designs, including variations in widths and lengths. Those skilled in the art will further understand that the rigidifying support  72  may be divided or “splayed out” into multiple generally-rigid members or “fingers” across the resistive surface  76 , in a manner similar to the fingers or divisions found in a bat wing. 
     The spacing hole  78  and the spacing recess  80  may be cut, drilled, formed, or otherwise placed in the rigidifying support  72  proximate the hand grip  36  to focus water displacement on the resistive surface  76 . This, in turn, moves the resistive center  64  further away from the hand grip  36 , advantageously increasing the efficiency of aquatic propulsion. The hand grip hole  82  may be cut, drilled, formed or otherwise placed in the rigidifying support  72  to allow for comfortable and secure placement of the hand  54  around the hand grip  36 . 
     The paddle&#39;s leading edge  70  may be defined as an edge or side that first ‘cuts’ or ‘slices’ through the water on a return or non-power stroke during swimming. Referring again to FIG. 2, the paddle  34  may be further characterized as having a steering radius  68 , defined by a perpendicular distance from the leading edge  70  to a line  69  running through the hand  54  and the forearm  56 . The present invention teaches that the leading edge  70  should be inline or generally proximate and parallel to the line  69  running through the hand  54  and the forearm  56 . In other words, the steering radius  68  should not typically extend much past the hand  54 , thereby enhancing a user&#39;s ability to perform directional adjustments. When the steering radius  68  is small, the effect is similar to steering an automobile with its front wheels; however, as the steering radius is extended, the effect is similar to steering an automobile with its rear wheels. The small steering radius  68  provided by the present invention advantageously aids user control, in contrast to prior types of devices directed toward enhancing human propulsion in water. In an exemplary embodiment, the steering radius is approximately three inches. 
     The hand grip  36 , the forearm member mount  38 , the elongated forearm member  40 , the forearm support  42  and the rigidifying support  72  may be constructed using material that is rigid, strong, light weight, UV protected and corrosion resistant, as well as attractive and hydrodynamic. In some embodiments, it may be advantageous for the rigidifying support  72  to have some amount of flexibility in order redirect forces, channel water flow and relieve stress. Many conventional types of plastics, rubber, metal alloys or the like would be suitable for construction of the present invention. For example, High-Density Polyethylene (HDPE), Aluminum, Titanium, and/or Carbon fiber materials may be employed in construction of the present invention. 
     The resistive surface  76  may be constructed using material that is flexible, strong, light weight, UV protected and corrosion resistant, as well as attractive and hydrodynamic. Many conventional types of plastic, rubber, metal alloys or the like, would be suitable, including one or more of the aforementioned materials. The desired flexibility of the resistive surface  76  may depend on the particular application of the present invention, and may be determined by material type and/or material thickness. For example, a novice user  30  may desire greater flexibility to reduce fatigue, while a more experienced user  30  may want less flexibility for higher performance. The resistive surface  76  may be manufactured from the same material as the rigidifying support  72 , but typically manufactured thinner in order to provide a desired amount of flexibility. This allows the paddle  34  to be manufactured using a single injection molding process. The boundary between the rigidifying support  72  and the resistive surface  76  may be abrupt, or a gradual taper as best suits any given application. Alternatively, the resistive surface  76  may be constructed using a material different from that of rigidifying support  72 , and laminated, bolted, welded, or otherwise secured to the rigidifying support  72 . 
     The desired buoyancy or density of the material or materials used to manufacture the aquatic propulsion device  32  may be selected based upon application. For example, scuba and underwater applications may require materials characterized by neutral or slightly negative buoyancy, while snorkeling and surface water applications may find materials providing increased buoyancy advantageous. 
     As with many manufactured products, cost, manufacturability, and intended application relative to any given choice of materials must be considered. The aforementioned elements may be manufactured from conventional materials using conventional injection molding, machining and/or similar techniques. 
     FIG. 4 illustrates an exploded view of an aquatic propulsion device  32  constructed in accordance with the present invention. A rotational attachment screw  100  may be used to secure the forearm member mount  38  to the elongated forearm member  40 . The tether pin  86  may also be used to further secure the forearm member mount  38  to the elongated forearm member  40 , in addition to securing one end of the tether  84  to the aquatic propulsion device  32 . 
     The elongated forearm member  40  comprises a front elongated member  102 , a back elongated member  104 , a rotational stop  106 , a spacing component  108  and a set of forearm member screws  110 . The forearm member screws  110  may be used to secure the front elongated member  102  to a first side of the rotational stop  106  and a first side of the spacing component  108 . The forearm member screws  110  may continue through the rotational stop  106  and the spacing component  108 , and may also be used to secure an opposing side of the rotational stop  106  and an opposing side of the spacing component  108  to the back elongated member  104 . A set of forearm support screws  112  may be used to secure the support bottom  44  to the elongated forearm member  40 , such that the support front  46  and the support back  48  are slidably adjustable to comfortably and securely fit the forearm  56 . Those skilled in the art will recognize that various embodiments of the aquatic propulsion device  32  may rely upon additional, fewer, and/or different types of securing elements than those shown in FIG.  4 . 
     FIG. 5 shows an aquatic propulsion device  32  folded into a storage position. The storage position reduces overall length to facilitate ease of transportation and/or storage. The elongated forearm member  40  and forearm support  42  may rotate around the rotational attachment screw  100  relative to the forearm member mount  38  and paddle  34 . In the folded storage position, the rotation of the elongated forearm member  40  and forearm support  42  is arrested or limited by the paddle&#39;s rigidifying support  72 . 
     FIG. 6 shows an aquatic propulsion device in an exemplary partially-folded position, wherein the front elongated member  102  has been removed to expose the structural interaction of the forearm member mount  38  and the rotational stop  106 . In a fully extended or usage position, as illustrated in FIGS. 1 through 4, the rotation of the elongated forearm member  40  may be arrested when the rotational stop  106  contacts a keyed stop  120  of the forearm member mount  38 . 
     FIG. 7 illustrates a first and a second resistive surface flex pattern  122 ,  123  that result when a person&#39;s hand  54  applies a force against the hand grip  36  along a first axis  60  and a second direction, axis, arc or travel path  61  that is generally opposite the first axis  60 , respectively. The magnitudes of the first and second flex patterns  122 ,  123  are dependent on 1) the amount of force applied to the hand grip  36  along the first and second axes  60 ,  61 , respectively; and 2) the rigidity and thickness of the material used to construct the resistive surface  76 . As mentioned above, increased flexibility may reduce a novice user&#39;s fatigue, while increased rigidity may increase power and control for a more experienced user. 
     FIGS. 8A,  8 B and  8 C are side views of an aquatic propulsion device  32  showing various degrees of a rotation orientation around the line  69  running through the hand  54  and the forearm  56 . Each of these rotational orientations is exemplified by rotating a user&#39;s hand  54  while leaving the forearm  56  and arm  52  in place. One skilled in the art will recognize that the rotational orientations illustrated in FIGS. 8A,  8 B and  8 C are for descriptive purposes only and represent an essentially infinite range of rotational orientations around the line  69 . Rotation of the aquatic propulsion device  32  around the line  69  may be used to 1) steer the aquatic propulsion device during the return or non-power stroke during swimming; and/or 2) adjust the exposure and thereby degree of water displacement by the resistive surface  76  during the power stroke while swimming. 
     FIG. 9 is an illustration of an alternate embodiment of an aquatic propulsion device  32  in which the forearm member mount  38  and the elongated forearm member  40  are secured by construction as a single rigid forearm member  130 . This embodiment simplifies the construction and reduces the amount of material and components required manufacture the aquatic propulsion device  32 . Such an embodiment may also improve the hydrodynamic properties of the invention. However, the storage position, as shown in FIG. 5, is not possible in this embodiment. This alternative embodiment may be advantageous for applications where performance and cost outweigh the convenience of the storage position for transportation and storage. One skilled in the art will see that there are any number of embodiments relative to the construction of the forearm member mount  38  and the elongated forearm member  40 , including, but not limited to, an embodiment in which they are secured by bolts, latches and/or a telescoping mechanism, thereby providing some of the advantages of the single rigid forearm member  130  while allowing for detachment to facilitate transportation and/or storage. 
     FIGS. 10 and 11 illustrate another embodiment of the present invention in which the forearm support  42  includes a support top  132  to facilitate a full encircling of the forearm  56 . For purpose of example, the front elongated member  102  has been removed in FIGS. 10 and 11 to expose the structural interaction of the forearm member mount  38  and the rotational stop  106 . As can be seen in FIGS. 10 and 11, the forearm member mount  38  may rotate around the rotational attachment screw  100  unencumbered by the rotational stop  106 , thereby allowing the forearm member mount  38  and paddle  34  to swing out of the way of the hand  54  when the hand grip  36  is released. In such an embodiment, the tether  84 , as shown in FIGS. 3 and 4, is not necessary because when released, the aquatic propulsion device  32  is prevented from drifting, floating, sinking or otherwise undesirably moving away from the person  30  by the forearm support  42 . This embodiment may be advantageous when unimpeded movement of the forearm  56  and arm  52  are not required. Those skilled in the art will understand that in yet another embodiment, one or more portions of the forearm support  42  could comprise a strap, which may be implemented, for example, using Velcro™ or other material. 
     FIG. 12 illustrates an embodiment of an aquatic propulsion device  32 , as taught by the present invention, wherein the leading edge  70 , rigidifying support  72  and the resistive surface  76  have or include a downward taper  140  on an end opposing the hand grip  36 . The downward taper  140  curves down and past the line  69  running through the hand  54  and the forearm  56 ; that is, the downward taper  140  curves toward a line essentially parallel to the elongated forearm member  40 . The downward taper  140  significantly reduces an average or effective steering radius  67 , defined as an average distance between the line  69  and the leading edge  70 , thereby increasing control and reducing the torque required to make directional adjustment to the paddle  34  through the water on the return or non-power stroke while swimming. In an exemplary embodiment, the effective steering radius  67  is approximately one inch; and the downward taper  140  curves such that the vertical distance or offset between the leading edge  70  and a tip or end  77  of the paddle&#39;s resistive surface  76  is approximately four inches. Those skilled in the art will recognize that the effective steering radius  67  and the extent of the downward taper  140  may vary in accordance with particular embodiment details. FIG. 13 illustrates yet another embodiment of the present invention, in which a bend  150  is formed in the rigidifying support  72 , thereby moving the resistive surface  76  out of a plane  152  formed by opposing ends of the hand grip  36  and the length of the elongated forearm member  40 . The bend  150  may be characterized by an angle  154  formed between the resistive surface  76  and the plane  152 . The angle  154  modifies the exposure of the resistive surface  76  to the water relative to the movement of the arm  52  during a power stroke while swimming. Various degrees of angle  154  may be advantageous for redirecting the resistive force  62  of the resistive surface  76  against the water in a more forward direction during a strongest portion of the arm&#39;s movement while swimming. This in turn may improve or enhance the aquatic propulsion properties of the present invention. In an exemplary embodiment, the angle  154  is approximately 15 degrees. Those skilled in the art will see that many different angles may be advantageous depending upon 1) the swimming application, such as, speed, distance, sport, or recreational use; and/or 2) the skill of the user. Those skilled in the art will also understand that an embodiment that incorporates the bend  150  may also incorporate the downward taper  140  shown in FIG.  12 . 
     FIG.  14 A and FIG. 14B are illustrations of an alternate embodiment of an aquatic propulsion device  32  in which the forearm support front  46  and the forearm support back  48  have a curved profile  200 , giving the forearm support  42  a c-shaped or generally c-shaped profile. Referring also now to FIG. 15A, an end view of an aquatic propulsion device  32  through the forearm support  42 , exemplifying the curved profile  200  of the forearm support front  46  and the forearm support back  48  and the generally c-shaped forearm support  42 , is shown. The effectiveness of the forearm support  42  in counter balancing a resistive action of the water against the resistive surface  76  during swimming motions or strokes is significantly enhanced by the curved profile  200  of the forearm support front  46  and the forearm support  48 , especially in a generally upward and inward direction  202  against the forearm support front  46  and a generally upward and outward direction  204  against the forearm support back  48 . 
     FIG. 2 depicts a person&#39;s forearm  56  placed or inserted into a previously described embodiment of the invention. Relative to a person&#39;s forearm  56  placed or inserted into the embodiment shown in FIGS. 14A,  14 B, and  15 A, the curved profile  200  of the forearm support front  46  and the forearm support back  48  improves comfort by better conforming to a curved shape of the person&#39;s forearm  56 . The curved profile  200  also distributes resistive forces against more surface area of the person&#39;s forearm  56 , thereby reducing pressure points. This force distribution and pressure point reduction may be particularly advantageous during swimming motions or strokes during which the device  32  may be mostly or entirely underwater, and/or in use for significant periods of time. 
     FIG. 15B is an illustration showing an end view of an aquatic propulsion device  32  through the forearm support  42 , in which the forearm support  42  includes an upward curve  201  on one end, thereby forming a support opening  50 . The support opening&#39;s width is increased by the upward curve  201  such that a person&#39;s forearm  56  is more easily able to move in and out of the forearm support  42  while retaining the comfort and improved support provided by the curved profile  200 . Those of ordinary skill in the art will see that the forearm support  42  may be constructed from many combinations of materials, construction techniques, sizes, shapes, widths, lengths and heights, including variations in the curved profile  200  and the upward curve  201 . 
     Referring again to the aquatic propulsion device  32  exemplified in FIG.  14 A and FIG. 14B, the paddle  34  may include a leading edge  70  and a resistive surface  76 . 
     The resistive surface  76  may be rigid enough to compensate for the lack of a rigidifying support  72  of the type shown in FIG.  3 . The rigidity and conversely, the flexibility, of the resistive surface  76  can be designed to match the application of the aquatic propulsion device  32  and skill level and/or preferences of a swimmer using the device  32 . 
     FIG.  16 A and FIG. 16B illustrate exploded views of additional details of an aquatic propulsion device  32  constructed in accordance with the present invention. The embodiment shown in FIGS. 16A and 16B includes a removable paddle  210 , a hand grip  36 , a set of paddle mounting holes  212 , a set of paddle mounting screws  214  and a paddle mounting slot  216 . The removable paddle  210  attaches to the hand grip  36  by sliding the removable paddle  210  into the paddle mounting slot  216  such that the set of paddle mounting holes  212  in the removable paddle  210  and in the hand grip  36  are aligned and can be secured by the set of paddle mounting screws  214 . This facilitates the use of interchangeable removable paddles  210  that may have various characteristics, including, but not limited to, rigidity, flexibility, color, buoyancy, shape and/or size. Those skilled in the art will see that the removable paddle  210  and the hand grip  36  may be attached using many alternate attachment mechanisms including, but not limited to, pins, clamps and/or push button released bindings. Those of ordinary skill in the art will understand that the removable paddle  210  may also be permanently attached to the hand grip  36  using alternate mechanisms including welding, adhesives and/or rivets. 
     FIG.  16 A and FIG. 16B additionally show an embodiment of an aquatic propulsion device  32  in accordance with the present invention that includes a forearm member mount  38 , a forearm member mounting hole  218 , a forearm member mounting bolt  220 , a forearm member mounting nut  222 , the elongated forearm member  40  and a elongated forearm member adjustment slot  224 . The elongated forearm member  40  may be slidably secured to the forearm member mount  38  by placing the forearm member mount  38  into the elongated forearm member adjustment slot  224  and placing the forearm member mounting bolt  220  through the forearm member mounting hole  218  and securing the forearm member mounting bolt  220  on the underside of the forearm member mount  38  with the forearm member mounting nut  222 . 
     Those of ordinary skill in the art will see that the elongated forearm member  40  is slidably adjustable along extent of the elongated forearm member adjustment slot  224  and the forearm member mount  38 . Additionally, by removing the forearm member mounting bolt  220 , the elongated forearm member  40  may be removed from the forearm member mount  38  for more compact storage and/or shipping. A resistive action between the forearm member mounting bolt  220 , the elongated forearm member  40  and the forearm member mount  38  can be used to secure a desired position of the elongated forearm member  40  lengthwise along a person&#39;s forearm  56  (not shown). Those of ordinary skill in the art will see that the resistive action between the elongated forearm member  40  and the forearm member mount  38  can be enhanced with the addition of a rough surface texture or saw orgear like teeth to a under side of the elongated forearm member  40  and a top side of the forearm member mount  38 . 
     Those skilled in the art will further see that in accordance with the present invention numerous other slidably adjustable mechanisms may be used to secure the forearm member mount  38  to the elongated forearm member  40  including insertion of the elongated forearm member  40  within a hole in the forearm member mount  38  using a well known telescoping action, or sliding the elongated forearm member  40  over and/or around a T-shaped groove or ridge in the forearm member mount  38 . Those skilled in the art will further recognize that the elongated forearm member  40  can be locked or secured into a position within or upon the forearm member mount  38  using many well known constructions, including, but not limited to, latches, ratcheting action and/or catches. 
     FIG.  16 A and FIG. 16B further illustrate an embodiment of an aquatic propulsion device  32  that includes a forearm support slider bolt  226 , a forearm support slider nut  228 , a forearm support mounting hole  230 , a forearm support slider guide  232 , the forearm support front  46 , the forearm support back  48 , a forearm support slider  234  and a forearm support slider slot  236 . The forearm support front  46  is attached to one end of the forearm support slider  234 . The forearm support back  48  is attached to an end of the elongated forearm member  40 . The forearm support slider  234  may be slidably secured to the elongated forearm member  40  allowing a width-wise adjustment of the forearm support  42 . The forearm support slider  234  is placed in the forearm support slider guide  232  and the forearm support slider bolt  226  is placed through the forearm support mounting hole  230  and then into and through the forearm support slider slot  236  and secured with the forearm support slider nut  228 . 
     Those of ordinary skill in the art will see that the forearm support slider  234  is slidably adjustable along extent of the forearm support slider slot  236  and the forearm support slider bolt  226 . Additionally, by removing the forearm support slider bolt  226 , the forearm support slider  234  and attached forearm support front  46  may be removed from the elongated forearm member  40  for more compact storage and/or shipping. A resistive action between the forearm support slider bolt  226 , the elongated forearm member  40  and the forearm support slider  234  can be used to secure a desired position of the elongated forearm member  40  widthwise across a person&#39;s forearm  56  (not shown). Those of ordinary skill in the art will see that the resistive action between the elongated forearm member  40  and the forearm support slider  234  can be enhanced with the addition of a rough surface texture or saw or gear like teeth to a under side of the elongated forearm member  40  and a top side of the forearm support slider  234 . 
     Those skilled in the art will further see that in accordance with the present invention numerous other slidably adjustable mechanisms may be used to secure the elongated forearm member  40  to the forearm support slider  234  including insertion of the forearm support slider  234  within a hole in the elongated forearm member  40  using a well known telescoping action, or sliding the forearm support slider  234  over and/or around a T-shaped groove or ridge in the elongated forearm member  40 . Those skilled in the art will further recognize that the forearm support slider  234  can be locked or secured into a position within or upon the elongated forearm member  40  using many well known constructions, including, but not limited to, latches, ratcheting action and/or catches. 
     FIG.  17 A and FIG. 17B show a side and perspective view, respectively, of an embodiment of an aquatic propulsion device  32  in which the forearm member mount  38  and elongated forearm member  40  are constructed along, aligned, or substantially aligned with respect to a leading edge  70 . This embodiment has similar usage characteristics to those of the previously disclosed embodiments the aquatic propulsion device  32 ; however, it may better fit a desired aesthetic and/or feel of a swimmer using the device  32 , such as a person  30  analogous to that shown in FIG.  1 . For exemplary purposes, the forearm member mount  38  and elongated forearm member  40  are shown joined in a single unary construction. Those skilled in the art will see that there are any number of embodiments relative to the construction of the forearm member mount  38  and the elongated forearm member  40  along the leading edge  70 , including, but not limited to, the various constructions disclosed in the alternate embodiments the aquatic propulsion device  32  as taught by the present invention. 
     FIG. 17C shows a perspective view of an embodiment of an aquatic propulsion device  32  in which the forearm member mount  38  and elongated forearm member  40  are constructed along, aligned, or substantially aligned with respect to a palm-side of a hand  54 , such as the hand  54  shown in FIG.  2 . One of ordinary skill in the art will see that the forearm member mount  38  and the elongated forearm member  40  may alternately be constructed along, aligned, or substantially aligned with respect to an opposed palm-side of a hand  54 . In another embodiment, the elongated forearm member  40  may be aligned with respect to the leading edge  70  while the forearm member mount  38  may not be; alternatively, the forearm member mount  38  may be aligned with respect to the leading edge  70 , while the elongated forearm member  40  may not be. In such embodiments, the elongated forearm member  40  may curve, angle, protrude or bend, making positional transitions with respect to a person&#39;s forearm  56 . Such positional transitions may aid forearm support and/or force distribution. One of ordinary skill in the are will see that the forearm member mount  38  and elongated forearm member  40  may have any number of positions, shapes, angles and/or curves as taught by the present invention. 
     FIG. 18 is a perspective view showing structural elements that facilitate a widthwise adjustment of a forearm support  42  of the aquatic propulsion device  32  of FIGS. 17A and 17B, and includes a width adjustment knob  240 , a width adjustment bolt  242 , a threaded width adjustment socket  244 , a forearm support slider guide  232  and a forearm support slider  234 . The forearm support slider guide  232  may be cut, drilled, formed, and/or otherwise placed in the elongated forearm member  40  proximate the end opposing the forearm member mount  38 . The forearm support slider  234  is place into the forearm support slider guide  232  and is slidably adjustable within the forearm support guide  232 . The width adjustment bolt  242  is inserted into the threaded width adjustment socket  244 . 
     The width adjustment knob  240  can be used to tighten/loosen the width adjustment bolt  242  within the threaded width adjustment socket  244  such that the width adjustment bolt  242  can lock or bind the forearm support slider  234  into a desired position, thereby allowing a widthwise adjustment of the forearm support  42 . Those skilled in the art will see that there are any number of embodiments relative to the construction of the forearm support slider  234  and forearm support slider guide  232 , including, but not limited to, using a well known telescoping action, or sliding the forearm support slider  234  over and/or around a T-shaped groove or ridge in the forearm support slider guide  232 . Those skilled in the art will further recognize that the forearm support slider  234  can be locked or secured into a widthwise position within the forearm support guide  232  using many well known constructions, including, but not limited to, latches, ratcheting action and/or catches. 
     FIGS. 19A and 19B are frontal views showing a motion and a flexural pattern of an aquatic propulsion device in accordance with a method of usage of the present invention. A person  30  such as the swimmer shown in FIG. 1 may alternately employ or perform propulsive, or power, strokes as shown in FIG. 19A, followed by return, or non-power, strokes as shown in FIG. 19B to propel themselves through water in a direction generally along a forward axis or travel path  250 . Relative to a propulsive stroke, the aquatic propulsion device  32  moves from an initial propulsive stroke position  252  proximate or above a person&#39;s waist or shoulder along the general direction of a propulsive axis or arc  256  to a final propulsive stroke position  254  proximate and beside or in front of a person&#39;s thigh or upper leg. This propulsive movement in turn causes the paddle  34 , which is oriented or held generally perpendicular to the propulsive axis  256  during the propulsive stroke, to displace a significant amount of water along the direction of the propulsive axis  256 , thereby propelling the person  30  forward along forward travel path  250 . The person  30  may adjust the particular orientation of the paddle  34 , which in turn may adjust the direction of propulsion during use. 
     A flexing action  260  of the paddle  34  caused by a resistive force of the water against the propulsive movement of the paddle  34  increases the displacement of the water in a direction or path opposite the forward travel path  250 , thereby increasing forward propulsion. The flexing action  260  advantageously aids in maintaining forward propulsion as a propulsive stroke is completed because a portion of the paddle  34  remains perpendicular or generally perpendicular to the forward travel path  250  for a longer time than would be the case in the event that the paddle  34  were rigid, thereby aiding water displacement in a direction opposite the forward travel path  250 . 
     The curved nature of the propulsive movement results in an additional, possibly undesired, and smaller or generally smaller water displacement component along a direction or vector generally perpendicular to a forward axis travel path  250 . This additional water displacement component may be countered by a similar but mirror image of the propulsive movement of an aquatic propulsion device  32  in the person&#39;s other hand. Moreover, the flexing action  260  of the paddle  34  may advantageously decrease an undesired or wasted displacement of the water in a direction or path perpendicular to the forward travel path  250 , thereby increasing efficiency and reducing fatigue. 
     One of ordinary skill in the art will see that a desired flexibility, stiffness, direction and curvature of a flexural characteristic of the paddle  34  may be constructed using well-known mechanisms, individually or in combinations, including, but not limited to, stiffening ridges or fingers, holes, slits or slots, grooves, variations in shape, variations in thickness, and/or choice of materials. 
     Relative to return strokes, as shown in FIG. 19B, movement of the aquatic propulsion device  32  begins from the final propulsive stroke position  254  and continues along a return path  258 , such that the paddle  34  is held or oriented generally parallel to the return path  258  to minimize the amount of water displaced by the aquatic propulsion device  32 . A return stroke may effectively return the aquatic propulsion device  32  to an initial propulsive stroke position  252 , from which another propulsive stroke may originate. Those skilled in the art will understand that a return stroke may generally retrace some or all of a propulsive stroke, and/or a return stroke may be used to reorient the aquatic propulsion device  32  to a new position prior to a propulsive stroke. 
     A flexing action of the paddle  34  during a return stroke may not be desired and might cause a wobble or vibration of the aquatic propulsion device  32  during the return stroke. Additionally, a flexing action of the paddle  34  along the leading edge  70  during the return stroke may also not be desired and might interfere with guidance of the aquatic propulsion device  32  during a return stroke. Consequently, the design of the flexural characteristics of the paddle  34  may take into consideration the desired attributes of both the propulsive and return strokes as well as, but not limited to, additional design considerations as disclosed herein. 
     FIGS. 20A and 20B are frontal views showing a motion and a flexural pattern of an aquatic propulsion device  32  in accordance with an alternate method of usage of the present invention. A person  30  such as the swimmer shown in FIG. 1 may alternately employ or perform a left-to-right cruising stroke as shown in FIG. 20A, followed by a right-to-left cruising stroke as shown in FIG. 20B to propel themselves through water in a direction generally along a forward axis or travel path  250 . Referring to FIG. 20A, an aquatic propulsion device  32  is positioned in a generally down and left outward direction below a person&#39;s waist in a left initial cruising stroke position  262 . 
     Relative to a left-to-right cruising stroke, the aquatic propulsion device  32  moves from the left initial cruising stroke position  262  along the general direction of a left-to-right cruising axis, arc, or travel path  266  to a right final cruising stroke position  264  in generally down and right outward direction below a person&#39;s waist. This cruising movement in turn causes the paddle  34 , which is oriented or held generally perpendicular to the left-to-right cruising axis  266  during the left-to-right cruising stroke, to displace a significant amount of water along the direction of the left-to-right cruising axis  266 , thereby propelling the person  30  forward along forward travel path  250 . The person  30  may adjust the particular orientation of the paddle  34 , which in turn may adjust the direction of propulsion during use. 
     A flexing action  260  of the paddle  34  caused by a resistive force of the water against the propulsive movement of the paddle  34  increases the displacement of the water in a direction or path opposite the forward travel path  250 , thereby increasing a forward propulsion. Additionally, such propulsive movement causes an additional, possibly undesired, displacement of water in a direction generally perpendicular to a forward axis travel path  250  that may be countered by a similar, but mirror imaged, right-to-left cruising stroke of an aquatic propulsion device  32  in the person&#39;s other hand. 
     Following a left-to-right cruising stroke, the person  30  may begin a right-to-left cruising stroke, as shown in FIG. 20B, to generate further forward propulsion. 
     Relative to right-to-left cruising strokes, movement of the aquatic propulsion device  32  begins from the final left-to-right cruising stroke position  264  and continues along a return path  268  such that the paddle  34  is held or oriented generally perpendicular to the right-to-left cruising axis  268  during the right-to-left cruising stroke, to displace a significant amount of water along the direction of the right-to-left cruising axis  268 , thereby propelling the person  30  forward along forward travel path  250 . 
     A right-to-left cruising stroke may effectively return the aquatic propulsion device  32  to the initial left-to-right cruising stroke position  262  from which another left-to-right cruising stroke may originate. Those skilled in the art will understand that a right-to-left cruising stroke may generally retrace some or all of a left-to-right cruising stroke, and/or a right-to-left cruising stroke may be used to reorient the aquatic propulsion device  32  to a new position prior to a left-to-right cruising stroke. 
     FIGS. 21A and 21B are a side extended and a side folded view respectively showing a seventh alternate embodiment of an aquatic propulsion device  32  constructed in accordance with the present invention in which a length-wise and a width-wise adjustment of a forearm support  42  are positioned, locked and/or secured with a single assembly. Referring also now to FIG. 21C, a perspective exploded view is shown that includes a forearm member mount  38 , an elongated forearm member  40 , a rotational attachment screw  100 , a forearm support  42 , a forearm support front  46 , a forearm support back  48 , an elongated forearm member adjustment slot  224 , a forearm support slider bolt  226 , a forearm support slider nut  228 , a forearm support mounting hole  230 , a forearm support slider guide  232 , a forearm support slider  234  and a forearm support slider slot  236 . 
     A rotational attachment screw  100  may be used to secure the forearm member mount  38  to the elongated forearm member  40 . The elongated forearm member  40  may be length-wise and width-wise slidaby secured to the forearm support  42  using the elongated forearm member adjustment slot  224 , the forearm support slider bolt  226  and the forearm support slider nut  228 . The forearm support back  48  is positioned or aligned with the elongated forearm member  40  such that the forearm support slider hole  230  is place below, or on the under side, of the elongated forearm member  40  and is inline with the elongated forearm member adjustment slot  224 , and the forearm support slider guide  232  is place above, or on top of, the elongated forearm member  40 . The forearm support front  46  is positioned or aligned above, or on top of, the elongated forearm member  40  and placed into the forearm support slider guide  232 . The forearm support slider bolt  226  is placed through the forearm support slider slot  236 , then through the elongated forearm member adjustment slot  224  and finally through the forearm support mounting hole  230  and secured with the forearm support slider nut  228 . 
     Those of ordinary skill in the art will see that the forearm support slider  234  is width-wise slidably adjustable along extent of the forearm support slider slot  236  and the forearm support slider bolt  226 . Those of ordinary skill in the art will further see that the elongated forearm member  40  is length-wise slidably adjustable along extent of the elongated forearm member adjustment slot  224  and the forearm support slider bolt  226 . Those skilled in the art will recognize that the forearm support  42  can be locked or secured into a position within or upon the elongated forearm member  40  using many well known constructions, including, but not limited to, latches, ratcheting action and/or catches. 
     FIG. 22 is a perspective view showing an eighth alternate embodiment of an aquatic propulsion device  32  constructed in accordance with the present invention that includes a wrist support  41  or a second support  41  for a person&#39;s forearm. Depending on usage, aesthetics, and/or construction techniques, the wrist support  41  may be secured to either the forearm member mount  38  or the elongated forearm member  40 . Those of ordinary skill in the art will see that there are many ways in which to secure the wrist support  41  to either the forearm member mount  38  or the elongated forearm member  40  including, but not limited to, constructed as a single unary piece, welding and/or bolting. One skilled in the art will further see that the wrist support  41  may also be adjustably secured to either the forearm member mount  38  or the elongated forearm member  40  using, but not limited to, latches, catches, bolts and/or other mechanisms as taught in accordance with the principles herein. 
     The wrist support  41  serves as a fulcrum for the leveraging of forces between the paddle  34  and the forearm support  42 . The fulcrum action of the wrist support  41  reduces the forces required by the person&#39;s hand  54 , as shown in FIG. 1, against a hand grip  36  when employing the aquatic propulsion device  32 . Those of ordinary skill in the art will see that the wrist support  41  may be constructed in many combinations of materials, construction techniques, sizes, shapes, widths, lengths and/or heights. 
     FIG. 23 is a perspective view showing a ninth alternate embodiment of an aquatic propulsion device  32  constructed in accordance with the present invention that includes an elongated forearm support  43 . Depending on usage, aesthetics, and/or construction techniques, the elongated forearm support  43  may be secured to either the forearm member mount  38  or the elongated forearm member  40 . Those of ordinary skill in the art will see that there are many ways in which to secure the elongated forearm support  43  to either the forearm member mount  38  or the elongated forearm member  40  including, but not limited to, constructed as a single unary piece, welding and/or bolting. One skilled in the art will further see that the elongated forearm support  43  may also be adjustably secured to either the forearm member mount  38  or the elongated forearm member  40  using, but not limited to, latches, catches, bolts and other mechanisms as taught by various embodiments of the present invention. 
     The elongated forearm support  43  provides a combination of wrist and forearm support characteristics of both the wrist support  41  and the forearm support  42  as taught by alternate embodiments of the present invention. Those of ordinary skill in the art will see that the elongated forearm support  43  may be constructed using many combinations of materials, construction techniques, sizes, shapes, widths, lengths and/or heights. 
     While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative and not restrictive of the current invention, and that elements of said embodiments may be combined in part or whole, and that this invention is not restricted to the specific constructions and arrangements shown and described since a wide range of modifications may occur by those ordinarily skilled in the art. The description herein provides for such modifications, and is limited only by the following claims.