Abstract:
Long fiber bristles are placed into channel (U-shaped) members forming bristle strips in the completed channel members. The completed channel members are retained in holding member that keeps four or more channel members parallel to each other forming a surface of bristle ends. The natural parting line of the bristle strips forms alignment features that may be used to align the golf swing. Shaped slots formed by two adjacent channel members act to capture a golf Tee. The shaped slots (V-channels) and the natural stiffness of the fiber bristles keeps a Tee upright and vertical when holding a golf ball. A golf mat assembly of four or more channel members may be used singly or assembled into practice surfaces. The practice surface provides an area for the golfer to stand while recessing the assembly so the surface of the fiber bristles conform to the practice surface.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    The present application claims priority to U.S. Provisional Patent Application Ser. No. 60/464,385, filed Apr. 23, 2003 which is incorporated herein by reference. 
     
    
     
       TECHNICAL FIELD  
         [0002]    The present invention relates to artificial surfaces from which golf balls are hit to practice ball striking with the feel of natural fairway grass.  
         BACKGROUND INFORMATION  
         [0003]    Golf is normally played on natural grass surfaces. To practice the golf swing, a golfer desires to strike a golf ball on surfaces that will react to the club face in much the same way as a natural grass surface. Most golf facilities provide practice ranges and there are facilities dedicated to practicing the golf swing while striking an actual golf ball with a golf club. Since the practice area receives considerable use, these facilities must continually move the area from which golfers practice to allow the grass to grow back. Wear, weather, etc. cause some facilities to have artificial surfaces for permanent or temporary use that will allow golfers an area to warm up or to practice their golf swing while striking a golf ball. Golf mats have been designed and made from a variety of plastic materials that are shaped to mimic grass. The artificial grass is normally attached to a rubberized base and placed over a concrete or otherwise hard impervious surface. When a golfer strikes a golf ball on such a mat, he or she may experience considerable shock when the club face strikes the rather stiff mat surface. When a pitching wedge or other short game club selection is made, the action of the swing requires striking in a downward direction toward the golf ball. Current mats do not allow this technique. Golfers like to practice both fairway shots and Tee shots. Tee shots are normally made using a Tee for holding the golf ball elevated above the ground or the surface of a golf mat. Artificial mats usually have such a rigid backing that a normal golf Tee will not easily penetrate it. As a result, golf mats use special Tees or fixed upright rubber tubes to mimic a Tee leading to a less than natural feel. Some golf mats are such that the golfer must move to natural ground to practice Tee shots.  
           [0004]    There is, therefore, a need for a golf mat that creates a natural feel when striking the golf ball. There is a particular need for a golf mat for use with short game clubs like the pitching wedge or nine iron or the long ball clubs like a Driver or Three Wood. There is also a need for the golf mat to accept standard golf Tees that can be variably placed on the golf mat according to the desires of the golfer.  
         SUMMARY OF THE INVENTION  
         [0005]    Long nylon fibers (fiber bristles) are made approximately twice as long as a desired vertical height. The fiber bristles are placed over and perpendicular to a slot opening in a long, straight U-shaped channel member. The center of the fibers are pressed down to the bottom of the slot and the opening is pressed closed forcing the nylon fibers to be bent and held into a vertical position wherein each fiber has a standing height of approximately one half of their unbent length. In this manner, a completed U-shaped channel member (completed channel member) with a row of fiber bristles is formed. A plurality of these completed channel members are retained into a holding member. In one embodiment, the holding member has mating features (slots) matched to the cross-section of the bottom of the completed channel member. The mating slots may be configured such that the completed channel member slides into the side opening in the mating slots. The holding member is configured to allow the completed channel member to be retained securely for use while also allowing completed channel members to be replaced in case of wear or for changing configurations. The holding member is designed to allow enough completed channel members to be installed to make a bristle surface large enough to provide an area for striking golf balls with a golf club. Since the nylon fiber bristles are long and stiff, they allow a ball to rest on the bristle surface much like grass. While the fiber bristles are stiff in the vertical direction, their length causes them to bend easily in a non-vertical direction. This allows the head of the golf club to traverse “into” the long fiber bristles simulating the taking of a divot on an actual fairway. The completed channel members have long, dense rows of fiber bristles. When the completed channel members are assembled into the holding member, they are placed close enough such that the natural forces of the bent fibers flare in a direction perpendicular to the length of the completed channel members creating a dense bristle surface. Since the completed channel members are removable, a golf mat made according to embodiments of the present invention may be repaired. Likewise, the spacing between completed channel members fitted into the holding member are such that they form a natural shaped slot for inserting a golf Tee. The stiffness and length of the nylon fiber bristles keep the golf Tee in a vertical alignment when inserted into the Tee slot.  
           [0006]    In striking a golf ball, it is important to align the body in a direction perpendicular to the desired ball flight. Many times golfers lay golf clubs parallel to the desired flight direction of a struck golf ball. The parting line between completed channel members in a golf mat made according to embodiments of the present invention serves to locate a region of the bristle surface where a standard wood Tee may be placed. Likewise, the parting line provides the golfer with an imbedded alignment marker for aligning his or her body relative to a desired ball flight path. In another embodiment of the present invention, selected completed channel members with fiber bristle rows of different coloration are placed adjacent to each other to enhance this natural Tee placement line or body alignment line.  
           [0007]    In another embodiment of the present invention, the fiber bristles of a selected completed channel members are trimmed such that the ends of the fiber bristles are not of the same length, rather, they form a “roughened” bristle surface such that a golf ball placed on the bristle surface will stay in a placed position without rolling. Various types of trimming or fiber bristle placement may be used to create an area of long fibers with lengths configured to provide a bristle surface that resists ball movement due to the golf mat being placed on a less than flat surface.  
           [0008]    In one embodiment of the present invention, the U-shaped channel members are made from a somewhat flexible material. In this embodiment, the long fiber bristles are placed across and perpendicular with the lengthwise slot of the U-shaped channel member. The slot in the U-shaped channel member is partially filled with a viscous quick curing epoxy. A tool (e.g., a wire), the length of the U-shaped channel member, is used to force the fiber bristles into the slot thereby causing them to bend vertical. A fixture may then squeeze the U-shaped channel member closed until the epoxy adequately cures forming flexible completed channel members. The cured epoxy is strong to hold the fiber bristles but flexible enough to allow the flexible completed channel members assembled into a likewise flexible holding member to form a flexible hitting area when placed over an uneven terrain. These flexible completed channel members may be used in a non-flexible holding member where their flexibility allows them to bend during assembly thereby reducing the number of removable parts.  
           [0009]    The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:  
         [0011]    [0011]FIG. 1A illustrates fiber bristles placed over a U-shaped channel member during assembly completed channel member according to embodiments of the present invention;  
         [0012]    [0012]FIG. 1B illustrates the fiber bristles partially pressed into the U-shaped channel member;  
         [0013]    [0013]FIG. 2A illustrates untrimmed fiber bristles locked into the U-shaped channel member;  
         [0014]    [0014]FIG. 2B illustrates the fiber bristles of FIG. 2A trimmed according to embodiments of the present invention to provide a surface that is suitable for keeping a golf ball from rolling;  
         [0015]    [0015]FIG. 2C illustrates the fiber bristles trimmed to provide a flat surface;  
         [0016]    [0016]FIG. 3 illustrates an assembly of four completed channel members in a holding member according to embodiments of the present invention;  
         [0017]    [0017]FIG. 4 illustrates the assembly of FIG. 3 with a golf ball set on the bristle surface formed by a plurality of completed channel members;  
         [0018]    [0018]FIG. 5 illustrates the assembly of FIG. 3 showing the shaped slot (V-channel) for holding a standard golf Tee according to embodiments of the present invention;  
         [0019]    [0019]FIG. 6 is another view of the assembly of FIG. 3 illustrating V-channel features and the alignment features according to embodiments of the present invention;  
         [0020]    [0020]FIG. 7 is a side view of the assembly of FIG. 3 illustrating a golf club head as it transitions into the fiber bristles as a golfer strikes a gold ball on the bristle surface;  
         [0021]    [0021]FIG. 8 is a view of a practice unit employing golf mat assemblies according to embodiments of the present invention;  
         [0022]    [0022]FIG. 9 is a view of another practice unit with a hinge for folding the unit for transport or storage according to embodiments of the present invention; and  
         [0023]    [0023]FIG. 10 is a flow diagram of method steps used in embodiments of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0024]    In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention. However, it will be obvious to those skilled in the art that the present invention may be practiced without such specific details. For the most part, details concerning materials, processes and the like have been omitted inasmuch as such details are not necessary to obtain a complete understanding of the present invention and are within the skills of persons of ordinary skill in the relevant art.  
         [0025]    Refer now to the drawings wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views. The nylon bristles in the following description may be referred to as being fiber bristles for simplicity. It is understood that other suitable materials (e.g., polymers) may be used and still be within the scope of the present invention. The fiber bristles in completed channel members are made to form rows of fiber bristles. These rows of fiber bristles are formed by placing fiber bristles into a U-shaped channel members. U-shaped channel members with fiber bristles are referred to as completed channel members. The fiber bristles are made of a material (e.g., nylon 6.0 or 6.6) are such that the frictional heating caused by the moving head of a golf club will not melt the fiber leaving residue on the club head and causing excessive wear.  
         [0026]    [0026]FIG. 1A and FIG. 1B illustrate steps in forming a completed channel member with fiber bristle strips according to embodiments of the present invention. Fiber bristles  102  are laid across U-shaped channel member  103 . U-shaped channel member  103  is shown in an end view showing a cross-section of its channel. An anvil piece  101  is used to force the fiber bristles  102  into the channel of U-shaped channel member  103 . Anvil piece  101  may be a wire of sufficient strength to force the fiber bristles into U-shaped channel member  103 .  
         [0027]    [0027]FIG. 1B shows the fiber bristles  102  partially within the channel of U-shaped channel member  103 . As the fiber bristles  102  are forced into the channel, they bend upward in a vertical direction by the action of wall sections  104  and  105 .  
         [0028]    [0028]FIG. 2A shows the fiber bristles  102  completely upright and vertical having an untrimmed top section  201 . Wall sections  104  and  105  have been bent inward onto the fiber bristles  102 . This action forces the fiber bristles  102  upright while anchoring them into the channel of U-shaped channel member  103  forming a completed channel member  200 .  
         [0029]    [0029]FIG. 2B illustrates the top section  202  of fiber bristles  102  in completed channel member  210  after they have been trimmed to a rough pattern to provide a surface that is suitable for holding a golf ball.  
         [0030]    [0030]FIG. 2C illustrates a top section  203  of fiber bristles  102  in completed channel member  220  trimmed to a flat level pattern.  
         [0031]    [0031]FIG. 3 is a side view of an assembly  300  according to embodiments of the present invention. Three completed channel members  302 - 305  are assembled into holding member  301 . Holding member  301 , in one embodiment, is an extruded aluminum piece with channels mated to the shape of U-shaped channel member  103  after its walls  104  and  105  have been crimped inward. This allows the U-shaped channel member  103  to slide into holding member  301  from the end. Because the completed channel members  302 - 305 , after crimping, have a wider bottom cross-section than a top cross-section, the crimped sides  104  and  105  keep the nylon bristles from coming out of holding member  301  during use. Shaped slots (shown here as V-channels)  307 - 309  are formed to hold the nylon bristle strips in place. However, V-channels  307 - 309  have additional functionality. V-channels  307 - 309  form visible lines due to the discontinuity between bristle strips that a golfer may use to align his body when using the assembly  300  as a golf mat. Likewise, the V-channels  307 - 309  are adaptable to capture the tip of a standard wood Tee (See FIG. 5). Since the fiber bristles are dense and stiff, the fiber bristles further hold a Tee upright. The bristle surface  306  forms the hitting surface for striking golf balls. In FIG. 3, the V-channels ( 307 - 309 ) formed by parallel U-shaped channel members may have additional features (not shown) to aid in their functionality for holding standard golf Tees while retaining mating features for coupling to holding member  301 . In general, V-channels ( 307 - 309 ) are shaped slots and may not be precisely V-shaped as shown in FIG. 3.  
         [0032]    [0032]FIG. 4 illustrates an end view of assembly  300  with a golf ball  401  sitting on a portion of bristle surface  306 . Holding member  301  retains completed channel members  302 - 305 . V-channels  307 - 309  are also shown.  
         [0033]    [0033]FIG. 5 illustrates the use of V-channels  307 - 309  for capturing a golf Tee  501 . In this view, golf Tee  501  is captured in V-channel  308 . The fiber bristles of completed channel members  303  and  304  hold Tee  501  upright. Golf ball  401  is shown on Tee  501 . Holding member  301  is also shown in this view.  
         [0034]    [0034]FIG. 6 is a top view of assembly  300  showing the length of nylon bristle strips in completed channel members  302 - 305 . V-channels  307 - 309  and the separation between completed channel members  302 - 305  are shown exaggerated to highlight the alignment features they form as the result of the discontinuity between completed channel members  302 - 305 . Embodiments of the present invention form a bristle surface of fiber bristle ends where the separation between rows of fiber bristles is small enough so the bristle surface is substantially continuous. The alignment features result from difference in the interface between parallel rows of fiber bristles. Attachment elements  601  and  602  are shown on each end of assembly  301 . These attachment elements may be to secure assembly  300  into the ground when assembly  300  is used as a yard practice mat. A depression may be formed such that assembly  300  would have bristle surface  306  substantially level with the ground surface. Nails or pegs (not shown) may be inserted in attachment features  601  and  602  to hold assembly  300  in place for use.  
         [0035]    [0035]FIG. 7 is a side view of assembly  300  showing nylon bristle strip  302 . Golf ball  401  is set on bristle surface  306  of assembly  300 . A golf club head  702  is attached to a shaft  701 . Shaft  701  is shown truncated to allow a magnified view. As the club head traverses an arc during a practice swing, club head  702  goes from position  704  to position  706 . As the edge of club head  702  contacts the first bristles  703 , they bend over allowing club head  702  to transition through the fiber bristles  703  much like a club head moving through natural grass on an actual golf fairway. This allows the edge of club head  702  to go slightly under golf ball  401  much like the taking of a divot on a natural grass surface.  
         [0036]    [0036]FIG. 8 illustrates a portion of a practice surface  800  for a practice range according to embodiments of the present invention. Two golf mat assemblies  300  are placed into depressions in practice surface  800  so that the bristle surface  306  of an assembly  300  is substantially level with the base surface  805  of practice surface  800 . Marks  801  and  802  illustrate where the feet of a golfer would be placed when using one of the assemblies  300  and swinging a club through an arc  804 .  
         [0037]    [0037]FIG. 9 illustrates a single golf practice mat  900  according to embodiments of the present invention. Assembly  300  is coupled to section  903  of golf practice mat  900 . Section  903  is coupled to section  906  with a hinge element  901 . This allows section  903  to be folded under section  906  to reduce the size of mate  900  for transport or storage. Foot placement marks  904  and  905  illustrate a golfer&#39;s position relative to assembly  300 .  
         [0038]    [0038]FIG. 10 is a flow diagram of method steps for making a surface for a golf mat according to embodiments of the present invention. In step  1001 , a row of fiber bristles are formed along the length of a channel member having features for retaining the channel member in a predetermined orientation, wherein the fiber bristles are substantially orthogonal to the length direction and width direction of the channel member thereby forming a completed channel member. In step  1002 , a plurality of the completed channel members are retained parallel to each other forming a bristle surface of bristle ends adaptable for holding a golf ball in a position for striking with a golf club. In step  1003 , the retained completed channel members are placed such that the bristle surface is substantially level with a base surface adaptable for standing on to strike a golf ball placed on the bristle surface.  
         [0039]    The present invention provides an assembly that contains rows of fiber bristles that have long fiber bristles that are stiff in the vertical direction for holding a golf ball. The long fiber bristles easily bend allowing a golf club head to move easily through them when striking a golf ball. The golf mat has natural alignment lines formed by the interface between adjacent parallel rows of fiber bristles and the shaped slots (V-channels) formed by adjacent completed channel members. The V-channels also serve to capture a wooden Tee while the fiber bristles hold the Tee upright and vertical simulating the natural position for Tee shots. The golf mat assembly may be used in an earthen depression, in a portable platform or within a long platform on a golf practice range. The completed channel members may be flexible or stiff. Flexible completed channel members may require the nylon bristles to be secured using an adhesive like epoxy. Flexible completed channel members allow the rows of fiber bristles to conform to an uneven surface allowing flexibility in use or to simulate uneven golf ball lies.  
         [0040]    The present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.