Abstract:
The invention provides for a golf teaching apparatus ( 10 ) including: an elongate arcuate track ( 12 ); a carriage ( 14 ) being slidable along the track; wherein the carriage includes receiving means ( 44 ) for releasably receiving a shaft ( 50 ) of a golf club ( 48 ). The apparatus further includes a mat ( 92 ), golf club displacement limiters ( 52 ), sensors ( 84 ) and a golf swing plane determiner ( 68 ). The carriage allows for freedom of movement of a shaft of a golf club relative to the track, and linear movement of the shaft relative to the receiving means.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates to a golf teaching apparatus, and more particularly to a golf teaching apparatus for use in teaching and training a golfer to adopt a correct golf swing. 
       BACKGROUND TO THE INVENTION 
       [0002]    Golf is a popular and highly technical sport, the backbone of which is a proper swing of the club used to hit the ball. A golf swing comprises an intricate composite movement of a player&#39;s hands, wrists, arms and body, all of which must be properly sequenced and timed, failing which the contact and thus engagement of the golf ball by a golf club will be adversely affected. 
         [0003]    In practice, many aspiring golfers are substantially self-taught, and tend to learn the game of golf, and thus the golf swing, independently without any substantial expert advice from a person suitably skilled in the sport. Advice is also often sought from other aspiring or amateur, but not professional, players, which often results in incorrect techniques being adopted, and in bad habits being formed. 
         [0004]    Also, aspiring golfers are often advised to start off with incorrect golf clubs. This is an incorrect approach as it results in golfers developing a golf swing that is not in harmony with the mechanics and dynamics of the human body. 
         [0005]    Various training aids have in the past been proposed for use in teaching an aspiring golfer a proper golf swing. However, most of these training aids share the common denominator of being complicated and expensive. Also, these devices often focus on a particular aspect of a golf swing, whilst neglecting other factors and therefore not providing comprehensive training for all facets of the complete golf swing. 
         [0006]    It has also been found that, in the game of golf, a player hits a stationary golf ball from a surface using a golf club. The surface may be of various types, but is typically in the form of a grass-covered substrate. When practising golf at home or at a driving range, it is advisable that a surface from which a ball is hit closely resembles the actual conditions that one would find on a golf course. 
         [0007]    In the past a number of synthetic golf mats have been proposed for use in simulating a grass surface found on a golf course. However, these mats generally share the common denominator of not closely resembling the actual playing conditions. For example, the synthetic grass often allows the club face to swing through the ball unperturbed, even if sub-optimal contact has been made, such as for instance when the club engages the golf mat too far behind the ball. 
         [0008]    Impact into the mat proximate the ball may also result in the ball being partially displaced prior to the club face engaging the ball, especially when the golf mat is too stiff, which may also lead to an inaccurate result as opposed to what the situation would have been had the ball been located on actual grass. In addition, it has been found that existing golf mats do not allow for effects such as spin to be properly simulated. 
         [0009]    U.S. Pat. No. 5,595,545 discloses a golf swing training apparatus having a circular track made by bending an elongate X-section extrusion of an aluminium alloy to form a plurality of partial circular track sections, which are then joined end-to-end to form a full 360 degree circular hoop. A multi-wheeled club guide cart rides on the track with a V-shaped circumference of each wheel mated to radially inner and outer opposed corner edges of the track member. The golf club includes a shaft of uniform diameter that rotates and slides in a linear bearing that in turn is connected by a pivot to the cart that allows rotation of the linear bearing and pivoting of the bearing for free movement of the golf club shaft in a plane orthogonal to that of the hoop throughout the swing. 
         [0010]    U.S. Pat. No. 4,583,740 discloses a device for teaching and practicing a proper golf swing, which enables the user to exercise and build the muscles necessary to a strong and effective golf swing, is provided for by this invention. The device consists of a tubular guide for directing a golf club during the proper swing, and a modified golf club with a weight mounted between two springs on said club for use with said device. The weight on the golf club is removable and thus may be varied depending upon the user&#39;s desired amount of weight. In addition to these benefits this invention is designed to allow the user to practice his or her golf swing while actually hitting a golf ball. 
         [0011]    U.S. Patent Nos. 1,567,530, 2,653,025 and 3,795,399 all disclose golf swing training devices having arcuate tracks and carriages which are movable relative to the track. The carriages engage a shaft of a golf club so that a golfer can insert a golf club and swing the golf club in a defined way. 
         [0012]    None of the prior art devices teach a golf swing training device having a carriage which carriage is adapted to release the shaft of a golf club when relative movement between the carriage and the golf club occurs. 
       OBJECT OF THE INVENTION 
       [0013]    It is accordingly an object of the invention to provide a golf teaching apparatus that will, at least partially, alleviate the above disadvantages. 
         [0014]    It is a further object of the invention to provide a golf training apparatus that will be a useful alternative to existing golf training apparatuses. 
         [0015]    It is yet a further object of the invention to provide a golf practising surface to be used in conjunction with the golf training apparatus according to the invention. 
       SUMMARY OF THE INVENTION 
       [0016]    According to the invention there is provided a golf teaching apparatus including:
       an elongate arcuate track;   a carriage being slidable along the track;   wherein the carriage includes receiving means for releasably receiving a shaft of a golf club.       
 
         [0020]    The receiving means is adapted to release the shaft of the golf club when movement of the carriage relative to the track is stopped, but the movement of the golf club is maintained. 
         [0021]    The receiving means may release the shaft of a golf club during an undesirable swing of the golf club. The receiving means may release the shaft of a golf club when sufficient force is applied to the golf club. 
         [0022]    The receiving means may be provided on a latching member that is pivotably connected to the carriage. Preferably the receiving means is in the form of two opposed, resilient tongue formations in between which the shaft of the golf club can be releasably engaged. 
         [0023]    A further feature of the invention provides for the track to be held in a required position by way of a frame, the frame being adjustable so as to adjust the position and the inclination of the track. 
         [0024]    The track may be at least partially circular, and preferably extends about three quarters about the circumference of a circle. There is provided for the track to be discontinuous, and thus to have a first end and a second end. 
         [0025]    A further feature of the invention provides for the track to be in more than one plane. 
         [0026]    The first end of the track preferably terminates in a tapered formation suitable for assisting in mounting the carriage onto the track. 
         [0027]    The track preferably comprises a plurality of interconnected arcuate sections which are secured to one another in an end-to-end configuration so as to form the elongate arcuate track. 
         [0028]    There is provided for the movement of the carriage relative to the track to be prevented when the carriage engages a swing plane guide member located adjacent and/or extending from the track. 
         [0029]    The carriage may be rotatable about the track, and axial movement of the carriage relative to the track may be prevented by the swing plane guide member if the carriage rotates beyond a predetermined angle. 
         [0030]    The swing plane guide member is preferably in the form of a connecting member that connects the track to a frame of the apparatus, and more preferably at least rear and bottom connecting members are provided. 
         [0031]    There is further provided for the shaft of the golf club to be slideable relative to the latching member of the carriage, and in a preferred embodiment relative to the receiving means that releasably engages the shaft of the club. 
         [0032]    At least one club displacement limiter may be securable to the shaft of the club so as to limit movement of the shaft relative to the latching member to a predetermined distance. More preferably, opposed club displacement limiters are securable to the shaft on opposing sides of the latching member. 
         [0033]    Another feature of the invention provides for the apparatus to include at least one sensor. A first sensor for detecting the speed of a shaft of a golf club relative to the track may be placed along the length of the track. Preferably the sensor is included inside the track, the track having a window through which the sensor detects the speed of a club relative to the track. A second sensor for detecting the angle of a face of a golf club relative to the frame may also be included. 
         [0034]    Yet a further feature of the invention provides for the apparatus to include a swing plane determiner. The swing plane determiner is preferably a movable elongate member extendable from a lower portion of the apparatus to an upper portion of the track. The elongate member is adjustable so that the swing plane of a number of golfers, all having differing swing planes, may be determined. 
         [0035]    The frame may further include a leg movement stabiliser. The leg movement stabiliser is in the form of a projection which projects from the frame to contact the leg of a golfer. The stabiliser is movable along the length of the frame so that the stabiliser may contact legs of golfers having different heights. 
         [0036]    Still a further feature of the invention provides for the apparatus to include a synthetic practising surface. 
         [0037]    The track may be pivotably connectable to the practising surface. Preferably the track is pivotably connected to the practising surface by means of two bottom connecting members. 
         [0038]    Still a further feature of the invention provides for the apparatus to include a further club displacement limiter for preventing a club engaged in the carriage from rotating beyond the club displacement limiter. The further club displacement limiter is a bar below the bottom of the track securable to the bottom connecting members of the frame. 
         [0039]    The synthetic practising surface for use with the apparatus includes:
       a planar base;   a sheet of synthetic grass located on one side of the base; and   an intermediate compensation layer sandwiched between the planar base and the sheet of synthetic grass, wherein a preferred hitting zone is defined by a zone of the golf practicing surface where the intermediate compensation layer is sandwiched between the planar base and the sheet of synthetic grass.       
 
         [0043]    The intermediate compensation layer may be made of a resilient material, and is preferably made from foam rubber or a material with similar properties. 
         [0044]    The planar base is preferably made of a substantially rigid material, and more preferably from polyethylene or fibreglass. The planar base may also be steel-reinforced. 
         [0045]    There is provided for the golf practising surface to include two separate sections, the two sections being pivotably connected to one another so as to be pivotable between an open position, where the two sections are located side to side for use as a practising surface, and a closed position wherein the two sections are located atop one another so as to reduce the total surface area of the golf practice surface, in so doing enabling easier conveyance and transportation of the golf practising surface. 
         [0046]    There is further provided for only one of the two sections to include an intermediary compensation layer, and thus a preferred hitting zone, the other section being provided for a user of the golf practising surface to stand on. 
         [0047]    A second aspect of the invention provides for the apparatus to be provided in a kit so that the apparatus may be assembled and disassembled. 
         [0048]    A third aspect of the invention provides for a golf teaching apparatus comprising:
       an elongate track;   a carriage; having a receiving means for receiving a shaft of a golf club and a sliding means for sliding along the track;   wherein the sliding means is slidable along the length of the track and is rotatable about the track; and   wherein the receiving means is pivotable relative to the sliding means so that the carriage allows for freedom of movement of a shaft of a golf club relative to the track, and linear movement of the shaft relative to the receiving means.       
 
         [0053]    A further feature of the invention provides for the track to be in more than one plane. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0054]    A preferred embodiment of the invention is described by way of a non-limiting example, and with reference to the accompanying drawings in which: 
           [0055]      FIG. 1  is a front view of the golf teaching apparatus in accordance with the invention; 
           [0056]      FIG. 2  is a side view of the apparatus of  FIG. 1 ; 
           [0057]      FIG. 3  is a perspective view of a latching member of the golf teaching apparatus; 
           [0058]      FIG. 4  is a perspective view of a sliding body of the golf training apparatus; 
           [0059]      FIG. 5  is a perspective view of a club displacement limiter forming part of the golf teaching apparatus; 
           [0060]      FIG. 6  is a perspective view of the carriage, comprising the latching member of  FIG. 3  and the sliding body of  FIG. 4 ; 
           [0061]      FIG. 7  is a plan view of a leg movement stabiliser forming part of the golf teaching apparatus; 
           [0062]      FIG. 8  is a side view of a golf club having the club displacement limiters and the carriage attached thereto; 
           [0063]      FIG. 9  shows a golfer holding a golf club in an address stance, the golf club being connected to the golf teaching apparatus in accordance with the invention; 
           [0064]      FIG. 10  is a front view of a golfer holding a golf club, the golf club being connected to the golf teaching apparatus in accordance with the invention; 
           [0065]      FIG. 11  is a side view of a golf teaching apparatus in a second embodiment; 
           [0066]      FIG. 12  is a schematic representation of the different stages of a back swing utilising the golf teaching apparatus; 
           [0067]      FIG. 13  is a schematic representation of the different stages of a down swing utilising the golf teaching apparatus; and 
           [0068]      FIG. 14  is a schematic representation of the follow through of the golf swing utilising the golf teaching apparatus. 
           [0069]      FIG. 15  is a perspective view of the golf teaching apparatus connected to the golf practising surface in accordance with the invention; 
           [0070]      FIG. 16  shows an exploded perspective view of the golf practising surface of  FIG. 15  in an open position; 
           [0071]      FIG. 17  is a perspective view of the golf practising surface in a partially closed position; and 
           [0072]      FIG. 18  is a perspective view of the golf practising surface in a fully closed position. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0073]    Referring to the drawings, in which like numerals indicate like features, a golf training apparatus in accordance with the invention is generally indicated by reference numeral  10 . The golf training apparatus, as is best seen in  FIG. 10 , includes a track  12 , a carriage  14  being axially slideable relative to the track  12 , and a frame  16  that keeps the track  12  in a required position. 
         [0074]    The track  12  is of a circular profile, and more particularly approximates three quarters of a circle. The track  12  is not continuous and thus includes a first end  18  and a second end  20 . The first end  18  includes a tapered guide formation  22 , which in use facilitates easy engagement of the carriage  14  onto the track  12 . The track  12  comprises a plurality of arcuate sections  24  which are connected end to end so as to form a substantially continuous track  12  between the first end  18  and the second end  20 . The track  12  may be made from a material being substantially circular or tubular when viewed in cross-section. The second end  20  includes an elbow extension  21  which is connected to the second end  20  by a hinge  23 . The elbow extension  21  is movable relative to the track  12  and also relative to the swing plane of a golfer. The elbow extension  21  prevents the carriage  14  from dismounting the track  12  at the second end  20  during a back swing of a golfer. 
         [0075]    The track  12  is kept in a required position by way of a frame  16 . The frame  16  includes a plurality of telescopic legs  26 , the telescopic legs  26  each being connected at one end to the frame  16  at an upper point and another end being connected to a mat  28  of the frame  16  at least at one lower point  27 . The track  12  is also pivotally connected to a golf practising surface in the form of a mat  28  that may also form part of the golf training apparatus  10 . The frame  16  is connected to the track  12  at an upper connection point referred to as the rear connecting member  30 . The frame  12  is further connected to the mat  28  by means of bottom connecting members  32 . 
         [0076]    The bottom connecting members  32  are pivotally connected to the mat  28  by means of pegs  33  extending from the bottom connecting members  32 . The pegs  33  are insertable into a socket  35  located on the mat  28 . The connecting members  30  and  32  also act as swing plane guiding members, as will be apparent from what follows hereinbelow. It will be appreciated that the telescopic functionality of the legs  26  of the frame  16 , combined with the pivotable connection to the golf mat  28 , or other surface to which the golf training apparatus  10  may be connected, allows for the track  12  to be adjustable to various angularly offset configurations relative to the surface on which the apparatus  10  is used. This allows different swing planes, and thus different club lengths, to be used in combination with the golf training apparatus  10 . The frame  16 , as discussed above, is best seen in  FIGS. 1 and 2 . 
         [0077]    Referring to  FIGS. 3 to 6 , a carriage used in the golfing apparatus  10  is indicated by reference numeral  14 . The carriage  14  comprises a sliding body  34  as well as a latching member  36 , respectively shown in  FIGS. 4 and 3 . The sliding body  34  has a channel  38  provided therethrough, the channel  38  being suitably configured and dimensioned slidingly to engage the track  12  of the golf training apparatus  10 . Wheels  40  are provided in order to ensure smooth actual movement of the sliding body  34  relative to the track  12 . The latching member  36  includes a body  42 , with a receiving means  44  extending from the body. The receiving means  44  comprises two opposing resilient tongue formations  46  that are adapted releasably to clamp the shaft of a golf club therebetween. In use, as is seen in FIGS.  3 , 4  and  6 , the latching member  36  is pivotally connected to the sliding body  34  so as to form a carriage  14  in which a club, engaged by the latching member  36 , would be able to pivot relative to the sliding body  34 . The pivotable connection is achieved by means of a bolt  45  extending from the latching member  36  which is insertable into an aperture  39  in the sliding body  34  and secured by a nut (not shown). This pivotable configuration will allow a proper golf swing to be executed while the carriage  14  is displaced along the track  12 . 
         [0078]      FIG. 8  shows a golf club  48  being ready for use with the golf training apparatus  10 . The latching member  36  of the carriage  14  has been secured to the shaft  50  of the golf club  48 , and the sliding body  34 , and in particular the channel  38  provided in the sliding body  34 , can now engage the first end  18  of the track  12 . 
         [0079]    Also shown in  FIG. 8  are two club displacement limiters  52 , which are secured to the shaft  50  of the golf club  48  so as to limit the displacement of the club shaft  50  relative to the latching member  36  and thus the carriage  14 . A club displacement limiter  52  is shown in more detail in  FIG. 5 . The club displacement limiter  52  is a body  54  with a slot  56  therein. A shaft  50  of a golf club  48  is insertable into the slot  56  of the club displacement limiter  52 . The body  54  of the club displacement limiter  52  has two opposing lip formations  58 , each lip formation  58  having an aperture through which a bolt  60  can pass. The body  54  is secured onto the shaft  50  by passing a bolt  60  through both apertures and securing the bolt  60  with a nut  62  as shown in  FIG. 5 . In this manner the slot  56  is closed so that the body  54  of the club displacement limiter  52  is secured to the shaft  50  of the golf club  48  as shown in  FIG. 8 . 
         [0080]    A further club displacement limiter in the form of a bar  64  is securable to the bottom connecting members  32  of the apparatus  10 , as shown in  FIG. 1 . The bar  64  extends between the two bottom connecting members  32  so that the bar  64  is substantially horizontal above the mat  28  and above a golf ball when positioned on the mat  28 . The bar  64  will prevent the shaft  50  of a golf club  48  held in the carriage  14  from rotating downwards beyond the bar  64 . Such rotational movement of the golf club  48  is caused by the position of a golfer&#39;s shoulders, arms and back while preparing for the back swing, as well as during the forward swing. The incorrect positioning and movement of the shoulders, arms and back during the swing is corrected, as certain movements will be prevented due to the presence of the bar  64 . The position of the bar  64  is adjustable to accommodate the height and stance of different golfers. 
         [0081]    A swing plane determiner in the form of a flexible chord  68  is provided, as shown in  FIG. 10 . The chord  68  includes a hook  70  at one end so that is attachable to the mat  28 , preferably at a position on the mat  28  in front of a ball  66  to be hit. The chord  68  is then extended to an upper portion of the track  12  and attached via another hook  70  at the opposite end of the chord  68 . It will be appreciated that an apparatus according to the invention may be adapted to accommodate left and right-handed golfers. A shoulder and leg of a golfer that are closest to the track are referred to as a trailing shoulder and trailing leg respectively. The correct position of attachment of the chord  68  to the upper portion of the track  12  is determined by ensuring that the chord  68  passes over the middle of a clavicle of a golfer&#39;s trailing shoulder. The swing plane determiner will assist in indicating the most suitable inclination of the track  12  relative to the frame  16  or mat  28  for a particular golfer as the chord  68  will be in a straight line extending from the mat  28 , over the golfer&#39;s shoulder to the top of the track  12 . In this manner the swing plane of a number of golfers, all having differing heights and therefore swing planes, may be determined and the correct inclination of the track  12  selected. 
         [0082]    From the above description it is clear that a number of degrees of freedom are required to give effect to proper operation of the apparatus, whilst certain relative displacements must be limited or prevented altogether so as to ensure that a proper golf swing is simulated. It is for instance of utmost importance that the carriage  14  can freely be actually displaced relative to the track  12 , and also that the club shaft  50  can slide in the latching member  36  during the course of the golf swing. Due to the configuration of the golf training apparatus  10 , the carriage  14  and more particularly the sliding body  34 , can also rotate about the track  12 . However, the degree of rotation must in this instance be limited, so as to ensure that a uniform swing plane is obtained. The rear  30  and bottom  32  connecting members therefore act as swing plane guide members, which will prevent sliding of the carriage  14  if the carriage  14  has rotated beyond a pre-determined limit. Should the pre-determined limit be exceeded, the carriage  14  will catch on the connecting members  30  and  32 , and further movement of the carriage  14  relative to the track  12  will be prevented. The golf club  48 , and more particularly the club shaft  50 , will then disengage from the latching member  36  so as to ensure that no damage is caused to the club, the apparatus or the golfer. 
         [0083]    The apparatus includes a leg stabiliser in the form of a connectable rod  72  which may be connected to a telescopic leg  26  of the frame  12  as shown in  FIG. 2 . The rod  72  includes a connecting member  74  which includes an aperture  76  as shown in  FIG. 7 . The aperture  76  includes a screw-threaded hole  78  for receiving a locking screw  80 . The aperture  76  may be slid onto the bottom of a telescopic leg  26  and secured, in any position along the length of the telescopic leg  26 , by tightening the locking screw  80 . The rod  72 , at the free end thereof, includes a concave plate  82 . The rod  72  is positioned so that the plate  82  contacts and abuts the trailing leg of a golfer. The plate  82 , supported by the rod  72  and the frame  12 , will limit the movement of the leg of the golfer during the swing. By limiting the movement of the leg, rotational movement of the golfer&#39;s hips is also limited, thereby encouraging correct movement of an entire body of a golfer. 
         [0084]    The track  12  may further include a number of sensors. A first sensor  84  for detecting the speed of the back swing or down swing of a golfer is placed inside the tubular track  12  as shown in  FIG. 1 . A window  86  is provided in the track  12  at the position where the sensor  84  is placed so that, as the carriage  14  connected to the golf club  48  passes over the window  86 , the sensor  84  detects the speed of the carriage  14  relative to the track  12 . In this way the speed of either a back swing or down swing may be determined. 
         [0085]    A second sensor (not shown) is included in the apparatus  10  for detecting the angle of the face  88  of a golf club  48  which rests on the mat  28 . The sensor is attachable to the connecting member  32  of the track  12 . The sensor will indicate the correct angle of the face  88  of the golf club  48  and alert the golfer so that he may adjust the angle of the club face  88 . The angle of the face  88  of the golf club  48  is important, as an incorrect angle will result in the face  88  of the golf club engaging the ball  66  incorrectly and the shot being off course. In use, best seen in  FIGS. 10 to 14 , a golfer attaches his or her club  48  to the latching member  36 , and the sliding body  34  is then slid onto the semi-circular track  12  while the club  48  is connected to the carriage  14 . The golfer then attaches the club displacement limiter  52  to the golf club shaft  50 , and sets it to a height on the shaft  50  of the golf club  48  that is equal to the distance between the club head, when grounded directly behind a ball, and the carriage  14 . The purpose of the club displacement limiter  52  is to prevent the player from pulling upwards as he or she attempts to strike a golf ball  66 . 
         [0086]    As the club  48  is swung, it is constrained to move in a pre-determined plane by way of the carriage  14  engaging the track  12  throughout the entire back swing. The player will also not be able to sway too far sideways as either the club displacement limiter  52 , or the club diameter relative to the latching member  36 , will prevent the club from being excessively displaced relative to the carriage  14 . The player will further be limited by the leg movement stabiliser  72  which limits movement of the legs of the player. The elbow extension  21  at the second end  20  will prevent the carriage  14  from dismounting the track  12  during a back swing of a golfer. 
         [0087]    At the top of the back swing the player will be forced to stay on the pre-determined plane by means of the rear connecting member  30  which acts as a rear swing plane guide member. On the back swing, the carriage  14  will slide over the rear-connecting member  30  at the top of the back swing. However, should the player alter his or her swing plane on the back swing, the carriage  14  will not be able to glide over the rear-connecting member  30  due to the excessive rotation of the carriage  14  about the track  12 , thus informing the player of the deviation in the swing plane. 
         [0088]    On the down swing the rear connecting member  30  will in the same way as above stop the down swing when the swing plane is altered. Should an excessive amount of force be applied to the club  48 , the club  48  will shoot out of the latching member  36 , resulting in the carriage  14  staying on the track  12 . This will again let the player know that he or she has altered his or her swing plane. During the down swing, the bottom connecting member  32  also acts as a swing plane guide member in that the bottom connecting member  32  will prevent the player from changing his or her swing plane, as any change in the swing plan will cause the carriage  14  to be stopped by the bottom connecting member  32 . Again the club  48  will be released from the carriage  14  if excessive force is applied to the golf club  48 . The carriage  14  will then remain on the track  12  without the golf club  48  attached to it, thus informing the player of the change in the swing plane. During the downswing of a golfer, the carriage  14  will slide along the track  12  until the first end  18  is reached. The carriage  14  will then dismount the track  12  at the first end  18  so that the follow-through movement of the golfer can occur. During the follow-through movement, the golf club is swung upwards following a swing plane. If the follow-through swing plane is not correct, the golf club will strike the elbow extension  21  connected to the second end  20  of the track  12 . 
         [0089]    The hinge  23  connecting the elbow extension  21  to the second end  20  of the track  12  allows the elbow extension to be adjusted to suit the follow-through swing of different golfers. 
         [0090]    In a preferred environment of the invention the tongue formation  46  of the latching member  36  will be defined by a circular shaft holding channel  38  with a diameter of not less than 7 mm and not greater than 14 mm, a 7.5 mm groove being provided in said circular shaft holding channel  38  so as to allow the shaft  50  to be releasable relative to the latching member  36 . In this embodiment the sliding body  34  will include wheels  40  to facilitate smooth displacement of the sliding body  34  relative to the track  12 , but it will be appreciated that many other friction reducing configurations, such as bearings or even PTFE sleeves can be used to achieve the same functionality. 
         [0091]    Also, in this preferred embodiment the track  12  will consist of 4 to 5 segments 24 of equal length, which segments are connected to one another to form a three quarter circle. The inclination of the track  12  is typically adjustable to any position within a 70 degree range. 
         [0092]    The golf teaching apparatus in one embodiment may be attachable to a golf practising surface  28  as shown in  FIG. 15 . The golf practising surface  28  includes a planar base  90 , a synthetic mat  92  and an intermediate compensation  94  layer at least partially sandwiched therebetween. 
         [0093]    The planar base  90 , as is best seen in  FIG. 16 , is made from a substantially rigid material such as fibreglass or polyethylene, and comprises a shoulder  96  that surrounds a flat surface  98  being adapted for receiving the synthetic mat  92  and the intermediate compensation layer  94 . The planar base  90  furthermore comprises a first section  100  and a second section  102 , the first section  100  and the second section  102  being connected to one another by way of a hinge  104  so as to be pivotable between an open position where the first section  100  and the second section  102  are located side by side, and a closed position when the first section  100  and the second section  102  are located atop one another as shown in  FIGS. 15 ,  17  and  18 . 
         [0094]    A synthetic mat  92 , which comprises a substrate with synthetic grass being provided thereon, is secured to the flat surface  98  of the planar base  90 . At least one aperture  106  is provided for receiving the intermediate compensation layer  94 , as well as a further synthetic mat  108 . The further synthetic mat  108  is a specially designed synthetic mat that resembles the actual feel and grip of a grass surface found on an actual golf course. In particular the height of the pile of the mat is between 7 and 13 mm. 
         [0095]    The intermediate compensation layer  94  is also secured to the flat surface  98  of the planar base  90 , and the further synthetic mat  108  is secured on top of the intermediate compensation layer  94 , thus sandwiching the intermediate compensation layer  94  between the flat surface  98  of the rigid planar base  90  and the further synthetic mat  108 . There is also provided for the intermediate compensation layer  94  to extend over the entire surface of the planar base  90 , in which case only one synthetic mat will cover the entire upper surface of the intermediate compensation layer  94 . In such case the cross sectional configuration of the golf practising surface  28  will be uniform throughout the length of the golf practising surface  28 . 
         [0096]    However, in the preferred embodiment shown in the drawings, the intermediate compensation layer  94  is only provided at one end zone of the golf practising surface  28 , so as to define a hitting section  110  as well as a standing section  112 . The configuration is such that the hitting section  110  and standing section  112  can pivot relative to one another in order for the entire golf practising surface  28  to be moveable between an open position and a closed position as shown in  FIGS. 17 and 18 . A preferred hitting zone is defined by the area where an intermediate compensation layer  90  is present. 
         [0097]    In a second embodiment of the invention, as shown in  FIG. 11 , the track  12  is curved in such a way that the track  12  is not in a single plane. Such a track  12  will allow for further freedom of movement of a golf swing. Studies of the golf swings of many professional golfers have shown that a normal golf swing does not have a consistent plane but follows the track  12  as shown in  FIG. 11 . 
         [0098]    It is foreseen that the addition of an intermediate compensation layer  90  made from a soft but resilient material, such as foam rubber, will result in the dynamics of a club face engaging a golf ball approximating that of real life conditions when a golf ball is positioned on actual grass. The inventor has found that effects such as spin, hitting divots, and hitting a ball thick or fat, are very close to real life conditions when this particular golf practising surface  28  is utilized. Also, the golf practising surface  28  is easy to transport and to convey due to the entire assembly being foldable as a result of the hinged configuration. 
         [0099]    It will be appreciated that the above describes only two embodiments of the invention, and that there may be many variations in detail without departing from the spirit and/or the scope of this invention. For example, in another embodiment of the invention one bottom connecting member may be provided. Also, the second sensor may be located inside the mat in the hitting section. Also, the swing plane may be limited in different ways. For instance, the carriage may be adapted to be slideable relative to the track, but not rotatable, in so doing preventing rotation of the club, and thus deviation from the required swing plane. This may for instance be achieved by providing complementary engagement formations (e.g. tongue and groove) on the track and the carriage.