Abstract:
A tilting platform assembly comprises a base member having a dome shaped upper surface portion, and a platform member having an upper playing surface and a concave shaped lower surface portion, the concave shaped lower surface portion corresponding substantially with the dome shape upper surface portion of the base member and being movable relative thereto. A mechanism is provided for selectively fixing and releasing the dome shaped upper surface portion of the base member relative to the concave shaped lower surface portion of the platform member to permit the top playing surface to be disposed at a plurality of different orientations.

Description:
FIELD AND BACKGROUND OF THE INVENTION 
     This invention relates to a golf practice platform. More particularly, the invention relates to a golf practice platform which can be adjusted by the user so that at least a portion of the surface can be adjusted to be at different orientations relative to the horizontal. In this way, the golfer is able to practice on a surface which can more accurately emulate the conditions on a regular golf course and tailor his or her golf game to the actual environmental variations commonly found on golf courses. 
     In the past, there have been several attempts to create a golf tee-off practice device where the surface thereof can be adjusted in some way so as to vary its angle relative to the horizontal in order to provide a reality based practice device for golfers. For the most part, it appears that these devices are unwieldy, difficult to operate and are usually so heavy that they must essentially remain in one location because of the difficulty in moving them. They may require complicated and expensive hydraulic mechanisms to operate, electrical power for motors associated with the device, and metal framework to support the weight of the platform surface as well as the golfer when practicing. The golf practice platform of the present invention has a configuration and manner of operation which avoids many of the cumbersome features of existing golf practice platforms. 
     Therefore, various devices for tilting golf practice platforms have been proposed although there does not seem to be any presently in use at golf driving ranges. This absence of such tiltable platforms is probably due to their complexity, the high expenses for manufacturing, installation, operation and maintenance. They are, for these reasons alone, too expensive to be popular at conventional facilities for golfers. The devices which can be identified, as mentioned, use means such as hydraulics, belts, pulleys, motors, gears, shafts, multiple wedge shaped rings and the like to achieve their ability to vary the platform surface angle in some way. However, this complexity of construction will add unwanted height to the platform. Not only are they expensive to make but they also do not lead to zero or minimal maintenance or longevity. This is aggravated by the fact that these types of devices tend to spend their lifetime in the open, exposed to the elements, sun, rain, snow, dirt, sand and other degrading factors. Their parts and operation therefore deteriorate over time, making an investment in this type of apparatus questionable. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention, there is provided a tilting platform assembly comprising: a base member having a dome shaped upper surface portion; a platform member having an upper playing surface and a concave shaped lower surface portion, the concave shaped lower surface portion corresponding substantially with the dome shape upper surface portion of the base member and being movable relative thereto; and means for selectively fixing and releasing the dome shaped upper surface portion of the base member relative to the concave shaped lower surface portion of the platform member to permit the top playing surface to be disposed at a plurality of different orientations. 
     Preferably, the lower surface portion of the platform member comprises thereon a plurality of non-slip rubber feet, and a plurality of spring-loaded bar assemblies formed on the lower surface portion of the platform member. 
     According to another aspect of the invention, there is provided a tilting platform assembly comprising: a base member having a substantially dome shaped portion and a substantially central opening in the dome shaped portion; a platform member which is substantially flat and mounted on the base member so as to be movable relative thereto to permit the platform member to be disposed at a plurality of different orientations; and a release and secure assembly operable between a first unlocked position wherein the platform member can be moved relative to the base member and a second locked position wherein the platform member is fixed relative to the base member. 
     In one embodiment, the release and secure assembly comprises a locking wheel having a threaded shaft which extends through the central opening in the dome shaped portion, and a locking plate below the dome shaped portion of the base member which has a threaded bore for receiving the threaded shaft, wherein the tightening of the locking wheel causes the locking plate to move toward the platform member and abut and engage the dome shaped portion of the base member to prevent relative movement between the base member and platform member, and the loosening of the locking wheel causes the locking plate to move away from the platform member and disengage the dome shaped portion of the base member to permit relative movement between the base member and the platform member. 
     In another embodiment, the release and secure assembly comprises a locking plate, a handle movable between a first locking position and a second unlocking position, the handle having a cam surface, and a connector portion between the handle and the locking plate, wherein rotation of the handle between the first locking position and second unlocking position moves the locking plate into and out of engagement with the base member to respectively prevent and permit relative movement between the platform member and the base member. 
     In yet another form, the release and secure assembly comprises a lock plate in the dome shaped portion of the base member, a locking lever accessible to a user of the platform assembly, and a cable extending between the lock plate and the locking lever, the locking lever being movable between a first locked position wherein the cable is tensioned to cause engagement of the lock plate against the base member to prevent relative movement between the base member and the platform member, and a second unlocked position wherein the tension in the cable is slackened to cause disengagement of the lock plate from the base member and permit relative movement between the base member and the platform member. 
     According to another aspect of the invention, there is provided a method of adjusting the orientation of a golf practice platform, the method comprising: placing a base member having a dome shaped upper surface on a substrate; mounting a platform member on the base member, the platform member having a top plane surface and a concave shaped lower surface portion which corresponds with the dome shaped upper surface portion of the base member; and selectively fixing and releasing the dome shaped upper surface of the base member relative to the concave shaped lower surface portion of the platform member so that the top playing surface can be selectively disposed at a plurality of different orientations. 
     This present invention therefore comprises a practicing aid for use by golfers who can, using the invention, practice driving golf balls while effectively standing on uneven or sloping ground surfaces as often happens in reality on the golf course fairway. Many golf courses will also have a “driving range” where golfers can practice driving golf balls as if from the starting tee-off position on the golf course itself. But these driving positions are almost always on substantially level ground. The only time the golfer may get to practice shots in an off level situation is actually during a golf game, where normal fairway conditions prevail. 
     The present invention therefore comprises an adjustable and tilting golf practice platform, that is preferably placed at or near a driving range, or in any other location for that matter, where the golfer can adjust the platform or surface thereof to various selected angles, stand on the platform, place the ball on the platform as well, and then practice driving such golf balls. This will allow and help the golfer to acquire the proper motor skills and expertise to cope with his body adjusting to an uneven stance, without having to be on an actual golf course. The golfer can continue to practice the same or similar shots on the uneven platform many times over to improve his or her skills, without being on a golf course where this type of activity would not be appropriate. Golfers are under constant pressure to keep moving on the golf course to prevent backups and delays for other golfers coming up behind them, so that repeatedly practicing shots from an uneven surface is for all practical purposes not possible on a regular golf course. 
     In one embodiment of the invention, the golf practice platform may comprise two basic components, namely, a base member and a movable platform mounted on the base member. The platform itself will preferably have no bearings, shafts, wires, motors, hydraulics or other unwieldy hardware on or attached to it, which tends to make its use impractical and expensive. Preferably, the base may be comprised of a lightweight but strong material such as for example stainless steel or aluminum, while the platform may be made of a material such as fiberglass. Both of these materials have properties which are well adapted to surviving and weathering the gamut of outdoor conditions. 
     In one form, the base may be a symmetrical dome-shaped structure with tabs appropriately placed thereon to be mounted to the ground in order to provide stability to the device. The platform will preferably be mounted on top of the dome shaped base structure. The platform will conveniently have a concave underside which will substantially match with and correspond to the curve and configuration of the dome. The platform may, in accordance with one aspect of the invention be held slightly raised from and off the surface of the dome by a plurality, preferably at least three, sliders which can be made of a material such as Teflon®. 
     In one form of the invention, these sliders are comprised of roller balls that are spring loaded, as will be described, with just enough force to lift the weight of the platform off the dome shaped structure. This will allow sufficient clearance between the dome and a plurality of rubber non-slip pucks or feet which are mounted to the underside of the platform. This combination of sliders and feet or pucks will allow the platform to be manually moved by effortlessly sliding it over the dome to a desired degree of tilt both in pitch or roll axes, as long as no person is standing on the platform. When the golfer has thus set the angle and orientation of the platform relative to the base, he or she then stands on the platform. The weight of the golfer will thereafter compress the spring loaded sliders until the rubber feet or pucks make contact with the dome. Due to the pressure of the multiple non-slip pucks exerted on the fairly gentle curve of the dome, the platform is then effectively locked in place on the dome, and relative movement between the dome structure and the platform is effectively prevented. 
     When the golfer steps off the platform, the platform is raised off the surface of the dome by the sliders and is freely movable thereover to be located to another position and angle. The drawings to be described show one embodiment of a typical layout of the slider units and the rubber pucks or feet mounted on the underside of platform to facilitate the action and operation of the invention in one of its forms. 
     Note that on the top surface of the platform there may be an area or portion where synthetic lawn or other suitable material can be glued or otherwise applied in order to simulate a golf course playing surface. This will provide a more realistic and true to life playing condition for the golfer to practice his drives. Furthermore, the top surface of the platform may have a sunken area or recess in order to hold a supply of golf balls ready for use by the golfer without having to change his position too significantly in order to make the practice session more useful. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a perspective view of a tilting golf practice platform in accordance with one aspect of the present invention; 
         FIG. 2  is a cross-section through the tilting golf practice platform shown in  FIG. 1  of the drawings; 
         FIG. 3  is a bottom view of the golf platform shown in  FIG. 1  of the drawings; 
         FIG. 4  is a cross-section through a golf practice platform in accordance with a further embodiment of the invention; 
         FIG. 5  is a detailed cross-sectional view of certain components of the golf practice platform shown in  FIG. 4  of the drawings; 
         FIG. 6  is a detailed view showing a locking mechanism for securing together relatively movable components of the golf practice platform in accordance with a further embodiment of the invention; and 
         FIG. 7  is a top view of a golf practice platform in accordance with one aspect of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The tilting golf practice platform of the invention will now be described with reference to the drawings. With reference to  FIG. 1  of the drawings, the tilting golf practice platform  10  of the invention is essentially comprised of a dome base  12  and a platform  14 . The dome base  12  of the practice platform  10  is placed on a surface  16  and may be secured thereto by fastening mounting tabs  18  formed on the dome base  12  to the surface  16  so as to prevent any sliding or movement of the dome base  12  on the surface  16 . The dome base  12 , while movable in the sense that it can be placed in any desired position without being permanently fixed to it, is, during operation of the practice platform  10 , at least temporarily secured to the surface  16 . 
     The platform  14  rests upon the dome base  12  and can be moved relative thereto. The platform  14  has an upper surface  20  and when the platform  14  is moved relative to the dome base  12 , the orientation of the upper surface  20  relative to the horizontal, which would typically be the surface  16 , a selected orientation of the upper surface  20  can be achieved. A golfer then stands on the upper surface  20  of the platform  14  and the selected orientation of the upper surface  20  will emulate the lie of the golf course thus enabling the golfer to practice shots, such as at a golf driving range, in a manner which would more accurately reflect actual conditions on a golf course. 
       FIG. 2  of the drawings shows the dome base  12  resting on a surface  16 . The dome base  12  has a circumferential rim  24 , with a plurality of tabs  18  extending outwardly from the circumferential rim  24 . Each tab  18  has an aperture  42  therein and, using a nail, screw or other type of fastener, the dome base  12  can be releasably attached to the surface  16 , as desired. 
     It will be seen in  FIG. 2  of the drawings that the dome base  12  includes a dome support surface  28  generally of arcuate shape, and preferably shaped so as to correspond in part to the circumference of a circle. The dome base  12  may be comprised of a metal, strong plastic or other suitable material, which is able to adequately support not only the platform  14 , but also the weight of a person standing on the platform  14 . 
     The platform  14  has a lower surface  46 , which is concave in shape, and, like the dome support surface  28 , has a shape which corresponds in part to the circumference of a circle. It will be seen from the drawings that the arcuate shape of the dome support surface  28  and the lower surface  46  of the platform  14  are substantially the same, thus enabling the platform  14  to slide over the dome support surface  28  in a manner to be described. 
     The lower surface  46  of the platform  14  has mounted thereon a plurality of non-slip rubber pucks or feet  50 . These are more or less equi-spaced in a circular configuration at a position near the edge of the lower surface  46 . Each of the feet  50  is preferably mounted within an appropriate recess  54  in the lower surface  46  of the platform  14 . Each of the feet  50  extends outwardly from the lower surface  46  by a small distance so that when the platform  14  is mounted on the dome support surface  28  a contact surface  56  of the feet  50  rests on the dome support surface  28 . Since the feet  50  are comprised of a non-slip, preferably rubber material, the platform  14  will not move relative to the dome base  12  when the contact surface  56  of the feet  50  is resting on the dome support surface  28 . While the size of each of the feet  50  is small, there are sufficient feet  50  located on the lower surface  46  of the platform  14  to ensure that the combined effect of the contact surfaces  56  on the dome support surface  28  keeps the platform  14  from moving relative to the dome base  12 . In  FIG. 3  of the drawings, the relative size and number of the feet  50  is illustrated in accordance with one aspect of the invention. Furthermore, the location of these feet on the lower surface  46  is also shown. However, it will be appreciated that different embodiments of the invention may show a different number of feet  50 , and their location and size may also vary according to specific design parameters. Further, any one platform  14  may have on its lower surface  46  feet  50  of different sizes and shapes, selectively located to provide optimal effect. 
     The platform  14  has formed therein a plurality of chambers  62 , as shown in  FIG. 2  of the drawings. In the embodiment shown in  FIG. 3  of the drawings, there are four equi-spaced chambers  62 . Each of the chambers  62  has an opening  64  in the lower surface  46  of the platform  14 . Each of the chambers  62  accommodates a spring-loaded bar assembly  34 . The spring-loaded bar assembly  34  comprises a spring  36  and a bar  38 . The bar  38  may comprise a roller ball or some other suitable structure which will serve the purpose, to be described below. 
     As best seen in  FIG. 2  the drawings, the spring-loaded bar assembly  34  is configured so that the spring  36  is located in the chamber  62 , and the bar  38  is located partially inside of the chamber, and extends partially outside the chamber  62  beyond the opening  64 . The spring  36  urges the bar  38  outwardly from the chamber  62 . Preferably, in one embodiment of the invention, the bar  38  may include tabs or stops which prevent the bar  38  from falling out of the chamber  62 . Generally, the bar  38  is movable between a first position in which it extends out from the chamber  62 , and a second position wherein it is pushed more into the chamber  62  against the bias of the spring  36 . 
     The spring  36  is selected so as to have sufficient force so as to raise the platform  14  off the dome support surface  28  when no additional weight is placed on the upper surface  20  of the platform  14 . Furthermore, the bar  38 , or at least a portion thereof, is preferably coated with Teflon® or some other suitable material so as to enable it to slide easily over the dome support surface  28 . In this way, a user of the golf practice platform  10  can easily move the platform  14  of the dome support surface  28  of the dome base  12  by lightly pushing it in the desired direction so that the upper surface  20  of the platform  14  will be in the desired orientation so as to emulate many of the non-horizontal surfaces typically encountered on a conventional golf course. 
     When the platform  14  is situated relative to the dome base  12  in a suitable position favored by the user, the user will then step onto the upper surface  20  of the platform  14 . The weight of the user will cause the bars  38  to be pushed by the dome support surface  28  into the chambers  62 , against the bias of the spring  36 . When this happens, the contact surfaces  56  of the feet  50  will engage the dome support surface  28 , and since the feet  50  are comprised of a non-slip material, the platform  14  will become fixed relative to the dome base  12 . In this way, the upper surface  20  of the platform  14  will be situated at the desired orientation by a simple adjustment, and will become fixed in that position when the user stands on the upper surface  20  of the platform  14 . Conversely, as soon as the user steps off the platform  14 , the action of the springs  36  will push the bars  38  toward the outside of the chambers  62  thus raising the feet  50  off the dome support surface  28  of the dome base  12 . The platform  14  will, in this situation, once more the cable of orientation adjustment when the user pushes or pulls the platform  14  relative to the dome base  12  to another desired position. 
     As will best be seen in  FIG. 2  of the drawings, the platform  14  has a projection  68  extending downwardly from the lower surface  46  thereof. The height of the projection  68  measured downwardly from the lower surface  46  is greater than the distance between the dome base  12  and the platform  14  which is normally created by the action of the spring-loaded bar assembly  34  when it is raising the platform  14  off the dome base  12 . The dome support surface  28  has a circumferential opening  70  therein and the projection  68  is able to move around in the opening  70  which is of larger dimension than the projection  68 . The projection  68  and opening  70  interaction provides limits to the extent of movement of the platform  14  on the dome base  12 . In essence, the opening  70  is bordered by an edge  72 , which represents the thickness of the dome base  12 . The projection  68  is free to move within the opening  70 , but eventually, the projection  68  will come into contact with the edge  72  defining the opening  70 . It will be appreciated that the projection  68  will not be able to move beyond the opening  70 , and this in turn limits the extent of movement of the platform  14  on the dome base  12 , to which the projection  68  is connected. 
     The upper surface  20  of the platform  14  may have formed thereon synthetic lawn  30 . However, any alternative covering, such as carpeting, plastic or other material may be used. Preferably, the lawn  30  may be easily removed and replaced in order that it may be periodically cleaned or completely replaced when worn. 
       FIG. 7  of the drawings shows a top view of a golf platform in accordance with one aspect of the invention. In this figure, there is shown an alternative locking mechanism by means of which the platform can be secured to the dome base, as will be described further below. However, this figure also shows the upper surface of the golf platform  10  of the invention which includes a defined ball tray  78  and  80 , which can also be utilized by the golf player to temporarily hold in a convenient manner those objects which may be related to golf practice. 
     In  FIG. 4  of the drawings, another embodiment of the invention is illustrated. In this figure, there is shown a golf practice platform  90  compromising a platform  92  and a dome base  94 , the dome base  94  preferably being comprised of a stainless steel material. The platform  92  has an upper surface  96 , a lower surface  98  and a fake grass or covering  100  formed thereon. The platform  92  is substantially planar or flat. The dome base  94  includes an outer rim  102  having a plurality of apertures therein, and through which a nail, bolt or screw  102  may be placed in order to temporarily secure the dome base  94  to a surface  106 . The dome base  94  has substantially centrally located therein an opening  108  through which at least a part of a release and secure assembly  110  can pass. By appropriate operation of the release and secure assembly  110 , to be described below, the position of the platform  92  can be selectively adjusted so that the orientation of the upper surface  96  can be varied according to the user&#39;s need. 
     The platform  92  has on its upper surface  96  a recess  114 , and on its lower surface  98  a circular wall  116 . 
     The release and secure assembly  110  is comprised of a locking wheel threaded shaft  120  which connects to a locking plate  122 . The locking wheel threaded shaft  120  is comprised of a wheel  126 , which is received within the recess  114  of the platform  92 , and a threaded shaft  128  which passes through an aperture  127  in the platform  92  and engages the locking plate  122 . The locking plate  122  comprises a plate  132  and a housing  134 , the housing  134  having an internal threaded bore  136  which receives the threaded shaft  128 . The housing  134  is received within the space  142  defined by the circular wall  116 . A rubber bumper  146  is located about the outside of the circular wall  116 . 
     The position of the platform  92  relative to the dome base and  94  can be easily and effectively adjusted using the release and secure assembly  110 . In order to move the platform  92  relative to the dome base  94 , the user will rotate the wheel  126  which has the effect of lowering the locking plate  122 . The platform  92  is then manually moved to the desired orientation. At that point, the wheel  126  is turned so that the shaft  128  engages more tightly and more securely within the internally threaded bore  136 . As it does so, the locking plate  122  is raised and eventually the edges  150  and  152  engage the lower surface  154  of the dome base  94 . When the wheel  126  has been sufficiently turned and tightened, the locking plate  122  will engage the dome base  94  with sufficient force so as to prevent further movement of the platform  92  relative to the dome base  94 . 
     The size of the opening  108  limits the extent of movement of the platform  92  relative to the dome base  94 . When the platform  92  has been moved to a position wherein the rubber bumper  146  engages the edge of the opening  108 , further movement of the platform  92  will be prevented. It should be appreciated that the size of the opening  108  will determine the extent of orientation from the horizontal which may be permitted by a particular golf practice platform  90 . 
       FIG. 5  of the drawings shows yet a further embodiment of a golf practice platform in accordance with the invention. In this figure, there is shown a golf practice platform  150  comprising a platform  152  and a dome base  154 . The platform  150  has a recess  156  on its upper surface  158  and a circular wall  160  extending from the lower surface  162 . A release and secure assembly  164  is provided, and comprises a handle  166 , a connector mechanism  168 , and a locking plate  170 . The handle  166  is pivotable and has a cam surface  171  which engages with the connector mechanism  168 . The connector mechanism  168  includes a first portion  172  which engages with the cam surface  171 , a tie rod  174 , and a connector bolt  176 . The tie rod  174  principally connects to the locking plate  170 , the locking plate  170  having edge  178 . As was the case shown in  FIG. 4  of the drawings, the edge  178  of the locking plate  170  can selectively engage with the lower surface  118  of the dome base  154 . A rubber bumper  182  surrounds the circular wall  160 , and contacts the dome base  154  at the edge of an opening  188  which is substantially centrally located in the dome base  154 . As previously described, the opening  188  determines by its size and shape the limits of movement of the platform  152  relative to the dome base  154 . 
     In operation, the mechanism illustrated in  FIG. 5  of the drawings is operated by moving the handle  166  between a first locked position which is illustrated in  FIG. 5  of the drawings, and an unlocked position, which is achieved by rotating the handle  166  through approximately 90° in a clockwise direction. When moved between the first locked position and the second unlocked position, the cam surface  171  formed on the handle  166  will cause the connector mechanism  168  to be raised or lowered. It is raised in the first locked position, and lowered in the second unlocked position. By raising and lowering the connector mechanism  168 , the locking plate  170  is correspondingly raised and lowered. When in the raised position, the edge  178  of the locking plate  170  will engage the lower surface  180  of the dome base  154 , fixing the platform  152  relative to the dome base  154 . When the handle  166  is moved upward to the unlocked position, the locking plate  170  will be lowered away from the dome base  154 , allowing the user to move the platform  152  to the desired position and orientation, and then fix it in that position and orientation by rotating the handle  166  and thereby causing the edges  178  to engage the dome base  154  and thereby secure the platform  152  relative to the dome base  154 . 
     Other features to note in respect of the golf practice platform  150  illustrated in  FIG. 5  of the drawings include a tab  192  which abuts against the floor of the recess  156  thereby ensuring a space  194  below the handle  166  when in the locked position, enabling the user to more easily grip the handle  166 . The platform  152  has fake grass  196 , a carpet, or other suitable material on the upper surface  158 . Further, the rubber bumper  182  engages the dome base  154  at the edge of the opening  188 , absorbing energy when bumping into the dome base  154 , to facilitate the comfort of the user when moving the platform  152  into the desired position. 
     Reference is now made to  FIG. 6  of the drawings which shows yet a further embodiment of a golf practice platform in accordance with another aspect of the invention. The golf practice platform  210  comprises a platform  212  and dome base  214 , as in previous embodiments described herein. Note that  FIG. 7  of the drawings shows for the most part a top view of the golf practice platform shown in this  FIG. 6 , with certain components, to be described, exposed for clearer illustration of this embodiment of the invention. 
     The embodiment shown in  FIG. 6  of the drawings includes a release and secure assembly  216  by means of which the platform  212  can be moved relative to the dome base  214  by the user, and locked in the desired position. The release and secure assembly  216  comprises a lock plate  218 , a spring  220 , a cable  222 , a first pulley  224 , a second pulley  226 , and a lever lock  228 . It will be seen that the lock plate  218  has slightly concave ends, and has an edge  230  which engages the undersurface  232  of the dome base  214  as has been described in previous embodiments. The locking plate  218  further comprises a substantially central cylindrical wall  236  and a rubber bumper  238  which surrounds at least a part of the cylindrical wall  236 , having a function already described above. 
     The spring  220  is connected to the center of the lock plate  218  by means of a pin or bolt  240 . At its other end, the spring  220  is connected to one end of the cable  222 . The other end of the cable  222  is pivotally connected to the lock lever  228 , at about its center. Between the spring  220  and the lock lever  228 , the cable  222  passes over the first pulley  224  and around the second pulley  226  before it reaches the lock lever  228 . As will be seen in  FIG. 7  of the drawings, the cable  222  is accommodated in a slot  244  so that it is below the surface of the platform  212 . 
     A recess area  246  is formed in the upper surface of the platform to  212 , and the recess area  246  accommodates the second pulley  226  as well as a part of the lock lever  228 . The lock lever  228  is connected pivotally at its one end  250 , and is rotatable about the end  250  between a first locked position  252  and a second unlocked position  254 . It will be seen by the relative positioning of the second pulley  226  and the lever lock  228  that when the lever lock  228  is in the lock position  252  it will provide additional tension to the cable  222 . When moved to the unlocked position  254 , that tension will be released, slackening the cable  222 . When the lock lever  228  is in the lock position  252 , the edge  230  of the lock plate  218  will engage the dome base  214 , and when the lock lever  228  is in the unlocked position  254 , the lock plate  218  will not be in contact with the dome base  214 . It therefore follows that the platform  212  can be moved relative to the dome base  214  when the lock lever  228  is locked, and such movement will be prevented when the lock lever  228  is in the unlocked position. 
     Is to be noted that the platform  212  has attached thereto a puck  260  which is designed and selected so as to easily slide over the dome base  214 . Other structural features of the golf practice platform  210  include a through hole  264  which accommodates the first pulley  224 , and allows the cable  222  to pass from the lower side of the platform  212  to the upper side thereof. Further, the dome base  214  includes the opening  268  of the type described in previous embodiments to limit the extent of movement of the platform  212  relative to the dome base  214 . The rubber bumper  238  absorbs and softens any shockwaves which may otherwise result when the cylindrical wall  236  impacts the edge of the dome base  214  which borders the opening  268 . 
     It will also be seen, based in  FIG. 7  of the drawings, that a portion of the locking lever  228  extends beyond the outer periphery of the platform  212  thereby placing it in easy and convenient reach of the user. The dome base  214  itself has a peripheral rim with attachment mechanisms which can be used to releasably secure the dome base  214  to the ground or other surface. The upper surface of the platform  212  may be covered with grass  268 , carpet or other suitable material, as desired. 
     The invention is not limited to the details described herein, and various modifications and embodiments may be made to the golf practice platform of the invention.