Title of the Invention Watercraft Board For Playing in the Water Field of the Invention The present invention relates to a watercraft board which can be safely and conveniently used during dabbling, and more particularly, to the watercraft board including a buoyant-type board having handles on its both sides, a propulsion load with one end being axially coupled to a rear side of the board and the other end having a webfoot which is used as a power source for moving the board, a propulsion foothold member assembly being axially coupled to a central portion of the propulsion load and capable of moving the webfoot right and left, and a blade being located on a bottom face of the board to help the board, which moves by the movements of the webfoot, move in a stable state without being inclined to any direction. The watercraft board of the present invention can be safely moved on the water and has been designed for easy assembly, disassembly and storage.

Background of the Invention Generally, a buoyant body for water sport is manufactured from rubber or synthetic resin and can be molded into various shapes such as a circle or rectangle. Air is injected into the buoyant body to be inflated. However, foreign objects (e. g. sticks and stones) can easily damage the buoyant body so safety is a primary concern.

A solution to this problem comes in the form of creating a buoyant body manufactured from foam resin. However, foam resin is limited in practical applications to such items as wind surfboards. A structure of a watercraft board (listed in Utility Model Official Gazette under Application No. 2019970013030) may be taken as one example for a related art board structure, in which a rope handle is provided on the circumference of the watercraft board so that a user can swim safely while holding the rope handle. This board structure, however, is problematic in that the user has to physically strive to move the board and the overall rate of speed is slow. As another example, a watercraft board (listed in the Utility Model Official Gazette under Application No. 2019930022473) may be given, in which the watercraft board includes buoyancy equilibrium wings located on both sides of its rear, and a mast on an upper side of a streamlined control room with a boarding kennel on its front face. In this watercraft board structure, however, a user on the board has to work with his/her feet to move the board. Accordingly, a moving speed of the board is slow and the user tends to feel tired easily. Also, (listed in Utility Model Official Gazette under Application No. 2019860012883), the following board structure was claimed. In this structure, a propulsion stick acting as a handle is driven into a bearing pin vertically formed on a rear part of the boat. When the propulsion stick, being designed to perform a seesaw action on a horizontal or inclined face, is moved right and left, upper and lower wings connected to the propulsion stick start operating and move the boat forward. In this instance, the boat can be moved forward only when a user in the boat pulls the propulsion stick right and left, thereby making the upper and lower wings operate in turn. Finally, a boat structure (listed in Utility Model Official Gazette under Application No. 2019910008131) will be given as the last example of the related art.

In this boat structure, a bottom of a tube type boat, a water discharge check valve made of a spring, and a supporting plate for a cylinder forming the water discharge check valve come in contact with each other and fixed together with bolt and nut. A piston with an elastic cord and an operating bar are attached to each other. A buoyant body is fixed to both ends of it and the water discharge check valve is connected to a spray pipe and in this way, a propulsion equipment come to operate. This propulsion equipment, however, has a complicated structure and can be driven by a limited way of spraying water.

Summary of the Invention The present invention relates to a watercraft board which can be safely used on the water and moved freely when provided for the use of skin scuba diving, the watercraft board including a board having handles on its both sides, a webfoot provided on one end of a propulsion load axially coupled to a rear side of the board and acting as a power source for moving the board, a propulsion foothold member assembly capable of moving the propulsion load from side to side, and a blade provided on a bottom face of the board to prevent the board, which moves by the movements of the webfoot, from being slipped from side to side. The watercraft board of the present invention can be moved in a stable state, thereby realizing simple and safe dabbling activities.

Brief Description of the Drawings The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

In the drawings: FIG. 1 is a perspective view illustrating a watercraft board of the present invention; FIG. 2 illustrates a disassembled perspective view of FIG. 1; FIG. 3 is a sectional view taken along the line A-A in FIG 1, illustrating coupling of a board, a propulsion load and a webfoot ; FIG. 4 is a sectional view taken along the line B-B in FIG. 1; FIG. 5 is a plan view of a watercraft board of the present invention, illustrating a webfoot moving right and left in a large angle as a propulsion foothold member assembly moves; FIG. 6 is a plan view illustrating a watercraft board with a safe belt on its side face according to another embodiment of the present invention; FIG. 7 is a side sectional view illustrating a watercraft board of which front upper face is formed to be protruding and one side inclined according to another embodiment of the present invention; FIG. 8 is a perspective view of a watercraft board having handles on its both sides and an intermediate board between the board and a propulsion foothold member assembly, according to another embodiment of the present invention; FIG. 9 is a disassembled perspective view of the watercraft board in FIG. 8; FIG. 10 is a sectional view taken along the line C-C in FIG. 8, illustrating coupling of each part; FIG. 11 is a perspective view illustrating a watercraft board having a bar with a waistband and a 2-storied propulsion foothold according to another embodiment of the present invention; FIG. 12 is a plan view of the watercraft board in FIG. 11; FIG. 13 is a sectional view taken along the line D-D in FIG. 12; and FIG. 14 is a plan view illustrating a watercraft board in operation according to the present invention, in which a webfoot moves right and left as a user operates a propulsion foothold member assembly.

Detailed Description of Preferred Embodiments Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

As shown in FIGs. 1 and 2, a watercraft board 100 of the present invention includes a buoyant-type board 101, a propulsion load 200, a propulsion foothold member assembly 300, and a webfoot 400. Handles 102 are provided on both sides of the board 101 and an axis installation member 103 is provided on a rear side of the board 101. A blade 104 is inserted within a groove 105 located upon the bottom of the board adding support to the left and right movement of the board.

The board 101 can be formed as a single body or by inserting a buoyant body within.

One end of the propulsion load 200 is inserted into the axis installation member 103 on the rear side of the board 101 and attached thereto with a bolt 500. The webfoot 400 is coupled to the other end of the propulsion load 200 with a bolt 501.

The propulsion foothold member assembly 300 for propelling the webfoot 400 is provided at a midpoint on the propulsion load 200. Also, on both sides of the propulsion foothold member assembly 300, are provided footholds 301 for supporting the user's feet, bands 302 for preventing foot slippage, and a supporting plate 303 for supporting the propulsion load 200. Finally, the propulsion foothold member assembly 300 is fixed into a groove 203 located in a central portion of the propulsion load 200 with a bolt 503.

The distance between the propulsion foothold member assembly 300 and the board 101 can be adjusted according to the height of the user by loosening the bolt 503 and repositioning the propulsion foothold member assembly 300 along the length of the groove 203.

FIGs. 3 and 4 are longitudinal and cross sectional views illustrating a board 101 being provided with a buoyant body 106 therein according to the present invention.

FIG 5 is a plan view illustrating a board in operation. It demonstrates how a user lying on the board holds handles 102 on both sides of the board and puts his/her feet into footholds 301 on both sides of a propulsion foothold member assembly so as to move the propulsion foothold member assembly 300 from side to side. This side-to- side motion is transferred down the length of a propulsion load 200 to a webfoot 400 located at a rear of the watercraft. Accordingly, the webfoot 400 attached to an end of the propulsion load 200 also comes to widely move from side to side. This side-to-side motion is converted to forward momentum thus propelling the watercraft through the water.

FIG. 6 shows a sectional view illustrating another embodiment of the invention in which a user is secured to the board 101 with a safety belt 107.

FIG. 7 is a side-sectional view illustrating a board in which the front edge of inclined.

FIGs. 8,9, and 10 illustrate a board according to another embodiment of the present invention, in which recesses containing handles 102 are located on both sides of the board 101. Also, a viewing glass window 110 is provided on the center of the board 101 so that a user on the board 101 may see into the water. U-shaped indentations 111 are carved into a rear section of the board 101 so that the user can have freedom of movement while lying on the board. A buoyant-type propulsion load 200 of rectangular or circular shape is provided in the middle rear side of the board 101.

On one end of the propulsion load 200 are located a number of coupling holes 204 for attaching the end of the propulsion load to the board 101 using a bolt 503. The length of the propulsion load 200 is adjusted by changing the position of the coupling hole 204.

An upper blade 205 and a lower blade 206 are respectively located on the upper end and the lower end of the propulsion load 200.

As shown in FIG. 1, the axis installation member 103 for inserting an axis member is located on one end of the propulsion load 200. An axis member 201 is inserted into the axis installation member 103 and fastened with a bolt 501.

The axis member 201 is joined with the propulsion foothold member assembly 300, and a webfoot 400 is fixed onto a rear end of the propulsion foothold member assembly 300 with a bolt 401.

FIGs. 11, 12, 13, and 14 illustrate a board with a user waist belt 207 according to another embodiment of the present invention. In this embodiment, a fixing node 209 is located on a lower end of the fixing buckle 208 of the waist belt 207. The fixing node 209 is inserted into a hole 211 of a coupling member 210 on an end of a propulsion load 200 and fastened thereto with a bolt 212. In the middle of the propulsion load 200 is located a length adjustment member 213 for adjusting length according to the user's height. A buoyant-type blade 214 is located on one side of the opposite end of the propulsion load 200 so as to adjust the buoyancy according to the amount of water being injected. A propulsion foothold member assembly 300 is provided on an end of the propulsion load 200. In this instance, 2-storied axial plates placed horizontally are axially coupled to 2-storied plates placed vertically, which are located in the central portion of the propulsion foothold member assembly 300. A webfoot installation member 410 is axially attached to one end of the vertical plates 310 by having an axis 312. An end of footholds 301 being axially coupled to both sides of the plates 313 of horizontal direction with a hinge 311 is axially coupled to both sides of an end of the webfoot installation member 410 so that the footholds 301 remain stable regardless of the motion of the webfoot 400. A length adjustment member 411 for adjusting the length of a supporting bar 412 is provided on a rear side of the webfoot installation member 410. The webfoot 400 is fixed to an end of the supporting bar 412.

The current design of the board can provide the user with a shoulder rack or a vest with waist belt 207.

By wearing the waist belt 207, the user can dive and swim upward and downward with complete freedom of movement. Thus, even with heavy equipment required for skin scuba diving, the user can enjoy fast forwarding speed by being provided with an efficient propulsion force compared when he/she swims only using webfeet.

Industrial Utilization Possibility As described, the watercraft board of the present invention can be safely and conveniently used during dabbling and realize fast and easy swimming even during skin scuba diving with the heavy equipment. The watercraft board of the present invention includes a buoyant-type board having handles on its both sides, a propulsion load with one end being axially coupled to a rear side of the board and the other end having a webfoot which is used as a power source for moving the board, a propulsion foothold member assembly being axially coupled to a central portion of the propulsion load and capable of moving the webfoot right and left, and a blade being located on a bottom face of the board to help the board, which moves by the movements of the webfoot, move in a stable state without being inclined to any direction. The watercraft board of the present invention can be moved in a stable state, thereby realizing simple and safe dabbling activities. Also, using the buoyancy and forwarding speed of the board, rescue activities in time of emergency can be done more efficiently.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.