Adjustable height practice golf tee

Abstract

This invention concerns an adjustable height practice golf tee for use with any of the existing golf hitting mats used at or incorporated into golf driving ranges, public and private indoor hitting areas, golf club fitting, testing and swing teaching stations, electronic golf swing analyzers and golf simulation video games. The invention incorporates a hidden thread design into two-piece and three-piece models to provide a greater range of adjustment and better durability than older designs. The inventive device uses a passive capture design which allows assembly without additional fasteners or retaining devices while preventing disassembly during use. A combination three-point ball seat reduces the tee's mass and effect on the ball launch while acting as a handle to facilitate precise and easy height adjustment.

1 . An adjustable golf practice tee comprising:
 a) a base comprising a flat flange portion and a tapered cylindrical upright portion having a top and a bottom; wherein said tapered cylindrical upright portion comprises a double female threaded cavity and a bottom opening into which at least one concentric additional part may be inserted; wherein said cavity extends from said bottom opening to a lower end of an unthreaded concentric hole at the top of said upright portion of said base; and wherein said unthreaded concentric hole is of smaller diameter than said threaded cavity; and wherein said tapered cylindrical upright portion is wider near said flat flange portion; and   b) a central ball support having a smooth cylindrical upper portion and a double male threaded lower portion, said double male threaded lower portion being situated to engage with said double female threaded cavity; wherein said double male threaded lower portion is of shorter length and greater diameter than said smooth cylindrical upper portion; wherein said double male threaded lower portion comprises a flat horizontal upper surface and a tapered lower end; and wherein said central ball support comprises a three pointed concave seat portion atop said smooth cylindrical upper portion, said seat portion extending from the top of said tapered cylindrical upright portion of said base; and   wherein said base and said central ball support are made from a flexible durable material.   
   
   
       2 . The adjustable golf practice tee of  claim 1 , wherein at least one flexible durable concentric intermediate part is inserted into said base through said bottom opening, said at least one concentric intermediate part having a top and a bottom; a smooth cylindrical upper portion having a cylindrical top feature of larger diameter than said cylindrical upper portion; a double male threaded lower portion having shorter length and greater diameter than said smooth cylindrical upper portion and comprising a flat horizontal upper surface; and a double female threaded cavity open at the bottom, wherein said cavity extends from said bottom opening to a lower end of an unthreaded concentric hole at the top of said intermediate part, and wherein said unthreaded concentric hole is of smaller diameter than said threaded cavity; said cavity capable of accepting said central ball support and engaging said central ball support's double male threaded lower portion. 
   
   
       3 . The adjustable golf practice tee of  claim 1 , wherein the underside of said base comprises a plurality of gripper protrusions.