the golf practice device according to the concepts of the present invention and how it functions can best be explained by reference to the attached drawings . as illustrated in fig1 - 11 , the preferred embodiment of the golf practice device 10 comprises a platform member 20 and a divot simulator insert 30 ; the divot simulator insert 30 , in turn , consists of a base member 40 , a carriage assembly 50 , a simulated turf surface 60 and a cover member 70 . referring to fig1 and 2 , the platform member 20 is generally square or rectangular in shape and is substantially similar to many of the commercially available golf practice mats , except for the cavity area 21 that is to receive the divot simulator insert 30 . the platform member 20 preferably consists of a base layer 22 made of a sturdy material , a cushioning layer 23 made of a resilient material such as rubber to provide proper support and stability and bonded to the base layer 22 by any conventional means , and a simulated turf layer 24 made of plastic to simulate grass and bonded to the cushioning layer 23 by any conventional means . it is to be understood that any platform composition that provides adequate cushion and has a non - skid surface that allows the golfer to maintain his footing through a golf swing may be used in an embodiment of the device without affecting its functions . a generally rectangular area is cut out through the cushioning layer 23 to create the cavity area 21 wherein the divot simulator insert 30 is installed . the upper portions of the side walls of the cavity area 21 are further recessed to accommodate the cover member 70 that is detailed below with reference to fig3 and 6 . referring to fig3 , the base member 40 is rectangular in shape with its longitudinal axis generally aligned with the direction of the line of flight of the golf ball to be struck from the surface of the golf practice device 10 , and has side frames 41 along the length dimension on either side and end frames 42 along the width dimension to increase rigidity . preferably , one of the end frames 42 has cutouts 43 that coordinate with the dimensions of the carriage retraction means 54 of the carriage assembly 50 that is detailed below . the side and end frames 41 , 42 preferably are l - shaped to increase the strength and tautness of the base member 40 . the cutouts 43 allow for the disassembly and reassembly of the carriage assembly 50 for cleaning and replacement of parts . preferably , support means 44 are sited at locations determined by the dimensions of the carriage tray 51 and the carriage extensions 53 . they are provided to support the carriage extensions 53 when pressure is exerted thereon and to ensure that the carriage extensions 53 move on a horizontal plane during use . the support means 44 are l - shaped bars in the drawings , though they may assume differing shapes or sizes without affecting their functions . mounting brackets 45 are affixed to the bottom of the base member 40 and the side frames 41 at positions determined by the length of the carriage retraction means 54 , and are provided to mount and hold in place the carriage retraction means 54 . on the bottom of the base member 40 between the support means 44 is an anti - friction layer 46 made of a low - friction material such as teflon ®. the base member 40 is preferably made of a metal or metal alloy but can be fabricated with generally any structural material such as metals , metal alloys or plastics , and can be either a single - piece construction or assembled from parts . as illustrated in fig3 - 5 , the carriage assembly 50 comprises a generally rectangular carriage tray 51 with sleeves 52 and carriage extensions 53 , and dual carriage retraction means 54 . each carriage retraction means 54 further consists of a guide rail 55 , one or multiple forward compression springs 56 and a rearward compression spring 57 , with the compression springs 56 , 57 generally having the same inner and outer diameters as the sleeves 52 . the guide rails 55 have thread means at the ends for affixing nuts 58 . the sleeves 52 are hollow , generally cylindrical tubes that are affixed to the sides of the carriage tray 51 along the length dimension and positioned toward the aft end . when assembled , the sleeves 52 are fitted over the guide rails 55 and sandwiched between the forward and rearward compression springs 56 , 57 such that the movement of the carriage tray 51 is controlled by the carriage retraction means 54 . the carriage tray 51 has upstanding edges on all sides . the carriage extensions 53 extend outward from the top of the edges on the forward and the aft sides so that the base member 40 remains obscured when the carriage tray 51 is in an extended position , as shown in fig7 and 10 . the maximum distance that the carriage tray 51 is allowed to travel during use determines the dimensions of the carriage extensions 53 . referring to fig5 , when the golf practice device 10 is assembled , the carriage retraction means 54 are positioned between the mounting brackets 45 with the guide rails 55 mounted on the mounting brackets 45 . the nuts 58 are attached to secure the guide rails 55 in place . the carriage tray 51 fits between the support means 44 ; the carriage extensions 53 are positioned over and supported by the support means 44 . the carriage tray 51 sits on the base member 40 when at rest and slides forward and back when in motion . the carriage tray 51 , sleeves 52 and carriage extensions 53 are preferably made of thermoplastic and can be either a one - piece construction or assembled from parts . in an alternate embodiment , the carriage tray 51 , and optionally the sleeves 52 and carriage extensions 53 , and the base member 40 are fabricated with filled and alloyed plastic composites possessing performance qualities such as : improved abrasion - resistance , lower static and dynamic friction , higher compressive strengths and improved creep resistance . when both the base member 40 and the carriage tray 51 are fabricated with such plastic composites , they are to be made of dissimilar polymers to ensure low coefficient of friction and thus may eliminate the need for the anti - friction layer 46 . as illustrated in the drawings , the simulated turf surface 60 , which may be made of any of the commercially available artificial turfs that are made of sturdy plastic and used for golf practice mats , is fitted inside the carriage tray 51 and preferably extends slightly above the top plane of the carriage tray 51 . the simulated turf surface 60 may be adhesively bonded to the carriage tray 51 or , preferably , removably affixed to the carriage tray 51 with attaching means such as hook - and - loop fasteners . when the simulated turf surface 60 is removably affixed to the carriage tray 51 in an embodiment of the present invention , it can be replaced when worn and different surfaces may be produced to simulate various golf course conditions such as rough fringes and uneven lies for the golfer to practice different shots . referring now to fig3 and 6 , the cover member 70 consists of a cover plate 71 , a frame member 72 and preferably a protective surface 73 . the cover plate 71 is generally rectangular in shape and slightly larger in dimensions as the base member 40 . the center portion is cut out to expose the simulated turf surface 60 and portions of the carriage extensions 53 . the frame member 72 , each segment having an inverted - l profile , extends down vertically from the underside along the circumference of the cover plate 71 . when assembled , the frame member 72 fits snugly around the outer perimeter of the base member 40 , and interlocks with the side and end frames 41 , 42 . the frame member 72 is removably attached to the base member 40 by any suitable conventional means such as screws , and is provided to strengthen the base member 40 and reduce or limit flexing when the device is in use . the flanges of the cover member 70 fit in the recessed spaces in the side walls of the cavity area 21 so that the divot simulator insert 30 can be fastened to the platform member 20 by any conventional means such as screws . in the preferred embodiment of the present invention , there is a protective surface 73 having the same dimensions as the cover plate 71 that is made of a resilient material and bonded to the top of the cover plate 71 by any suitable conventional means . the protective surface 73 is provided to help dissipate and absorb the impact force when the club head strikes the cover member 70 instead of the simulated turf surface 60 in the event of a missed hit . in use , the golfer places a golf ball on the simulated turf surface 60 and takes a swing with a golf club . referring to fig8 - 11 , when the club head impacts the device , the force imparted to the carriage tray 51 compacts the forward compression springs 56 and moves the carriage tray 51 , together with the simulated turf surface 60 , forward as directed by the guide rails 55 , thus simulating the feel to the golfer of striking a golf ball off natural turf and taking a divot . when the resistance from the forward compression springs 56 exceeds the forward force , the carriage tray 51 and the simulated turf surface 60 are then returned to their original position . rearward compression springs 56 are employed to absorb the retraction force and reduce shock to the aft end of the device . the sliding forward of the carriage tray 51 and the simulated turf surface 60 also reduces club head bounce and lessens stress on the golfer &# 39 ; s wrists and elbows , allowing the golfer to correctly practice his golf swing and decreasing risk of injury . fig1 illustrates a platform member 20 and divot simulator insert 30 configuration suitable for a right - handed golfer ; however , the divot simulator insert 30 can be detached from the platform member 20 , rotated 180 ° horizontally and reinstalled for use by a left - handed golfer . to conclude , with respect to the above description , it is to be understood that the optimal dimensional specifications for the parts of the invention , including variations in number , size , shape , form , placement , material and the method of fabrication and assembly , are deemed readily apparent to persons skilled in the art upon a reading of the foregoing description , and all equivalent specifications to those illustrated in the drawings and detailed in the description are intended to be encompassed by the present invention . further , it will be obvious to those skilled in the art that various modifications and revisions can be made to the embodiment shown herein without departing from the spirit and essential characteristics of the invention . it is therefore intended by the appended claims to cover any and all such modifications and revisions within the scope of the present invention .
a golf practice device is disclosed that simulates the response of natural turf when impacted by the golf club head . the device comprises a platform for supporting the golfer and a divot simulator insert installed in a cavity area within the platform . the divot simulator insert has a base ; a tray rests on top of the base with a simulated turf surface fitted therein . a cover is provided to conceal the interior and strengthen the base . when a ball placed on the simulated turf surface is struck by a golf club , the force imparted to the device sends the tray together with the simulated turf surface sliding forward , thus simulating the feel of hitting off natural turf and taking a divot . means comprising compression springs fitted over guide rails are provided to control the sliding forward and retraction to their original position of the tray and the simulated turf surface .