Patent Abstract:
A trampoline including: a frame adapted to rest on the ground or be mounted on a plurality of spaced apart legs; a plurality of spaced apart flexible and resilient plates extending upwards from said frame and connected thereto against relative movement therebetween; and a jumping mat operatively connected to said plates above said frame for movement with said plates upon a person jumping thereon.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a divisional application of Ser. No. 14/124,491 filed 7 Jun. 2012, which in turn is a National Phase entry of PCT/AU2012/000651, filed 7 Jun. 2012 which claims the priority of Australian Patent Application No. 2011902285 filed 9 Jun. 2011, Australian patent Application No. 2011904866 filed 22 Nov. 2011, Australian Patent Application No. 2011905244 filed 16 Dec. 2011, Australian Patent Application No. 2011905290 filed 19 Dec. 2011, and Australian Patent Application No. 2012901066 filed 16 Mar. 2012, all of which are incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    This invention relates to trampolines. The invention has particular application to recreational trampolines of the type used in playgrounds and homes but it may have application to sporting trampolines as well. 
       BACKGROUND 
       [0003]    For many years recreational trampolines have typically included a tubular steel frame which is supported on spaced legs with a flexible jumping mat secured to the frame by a large number of spaced apart extension springs which extend and contract as a person jumps on the mat in order to give “bounce.” The springs are usually connected to the tubular steel frame at one end via radial slots provided therein and to the mat via hooks or the like at the other end. Although trampolines can be made in many shapes, circular is probably the most popular in which case the frame is generally constructed of arcuate segments of round tube which are joined together in a spigot and socket arrangement with the end portion of one segment sliding into the end portion of the adjacent segment. 
         [0004]    It will be appreciated that the space between the jumping mat and the frame creates some difficulties for users in getting onto the mat, and when jumping on the mat the springs and the spaces therebetween can present some danger for anyone jumping too close to the edge of the mat. Consequently, modern recreational trampolines typically include a padded safety barrier (or “padding”) extending about the mat and covering the springs and the spaces therebetween. The padding is typically tied to the mat and/or the frame by ribbon ties or the like. Such trampolines typically include a safety barrier (or “net”) extending about the mat frame and attached to posts upstanding therefrom to prevent users from falling off the trampoline. 
         [0005]    Other forms of trampolines known as “soft edged trampolines” which do not require a frame about the edge of the jumping mat and do not use extension springs to support the mat have been developed in recent years. In such trampolines, the mat is typically supported on a large number of circumferentially spaced fibreglass rods which extend upwards, outwards and forwards around the mat from a frame under the mat and are connected to the edge of the mat at their upper ends. The rods are flexible and resilient so as to bend downwards and inwards as a person&#39;s weight comes onto the mat during jumping and to return to the original position as the weight comes off the mat causing a back and forth twisting motion of the mat. Such twisting action gives a different performance feel to users. 
         [0006]    The present invention is aimed at providing another type of trampoline which is reliable and efficient in use and which does not require extension springs to secure the jumping mat to the frame. The invention is also aimed at providing a trampoline which maintains the traditional feel of a trampoline more satisfactorily than presently known soft edged trampolines. The invention is also aimed at providing a trampoline which can be efficiently manufactured. 
       SUMMARY 
       [0007]    With the foregoing in view, the invention in one aspect resides broadly in a trampoline including: 
         [0008]    a frame adapted to rest on the ground or be mounted on a plurality of spaced apart legs; 
         [0009]    a plurality of spaced apart flexible and resilient plates extending upwards from said frame and connected thereto against relative movement therebetween; and 
         [0010]    a jumping mat operatively connected to said plates above said frame for movement with said plates upon a person jumping thereon. 
         [0011]    In one form of the invention a flexible and resilient rod or tube extends about the periphery of the jumping mat and is connected thereto for movement therewith and is also operatively connected to said plates for movement therewith. Such rod or tube may be in the form of connected or unconnected (or disconnected) segments in which form it is preferred that the segments be connected to the plates at about their mid-points so that each segment extends the same distance beyond both sides of the plate to which it is connected. When in the form of connected segments, the connection ideally allows for relative movement between segments as the mat moves up and down while a user is jumping thereon. In one such form, the mat is connected to a plurality of unconnected rod segments extending about its periphery so as to more or less form a circle and those rod segments are in turn connected to adjacent rod segments forming another circle outside the first circle and those segments are in turn connected to said-flexible and resilient plates. In one preferred form, the connection between the adjacent segments is via rigid coupling members while in another form they are via semi-rigid coupling members adapted to accommodate relative up and down and in and out relative movement between adjacent segments as well as some relative twisting movement. 
         [0012]    In another aspect, the invention resides broadly in a trampoline including: 
         [0013]    a frame adapted to rest on the ground or be mounted on a plurality of spaced apart legs; 
         [0014]    a plurality of spaced apart flexible and resilient plates extending upwards from said frame and connected thereto against relative movement therebetween; 
         [0015]    a jumping mat operatively connected to said plates about its perimeter above said frame, said plates being arranged for movement inwards and outwards towards and away from the opposite side of said mat in response to a user jumping on said mat. 
         [0016]    Preferably, said plates are sized so as to bend generally in only one direction, for example, in the case of a circular mat, the plates would only bend radially inwards and outwards, while in the case of a square mat the plates would bend directly towards the opposite side of the mat. In a preferred form, the plates each comprise laminated elongate layers of spring steel over a substantial portion of its length. In one such form selected to meet desired rebound characteristics for the mat the plate comprises different numbers of layers at different places along the length of the plate. 
         [0017]    Preferably, said spaced apart plates are connected to said frame by passing through spaced apart slots formed in said frame, the slots being suitably sized to form a tight fit about the lower end portions of the plates so as to prevent any significant relative movement therebetween. In such form, it is preferred that retaining means be provided to retain the plates in the slots. 
         [0018]    In this form of the invention it is preferred that the mat be connected to the plates adjacent their upper ends by connector assemblies incorporating a hook and a load bearing fitting mounted in a pocket formed in the mat adjacent its periphery. In such form, it is preferred that the hook be connected at one end to the mat via the load bearing fitting and to the plates at the other and via one or more hook openings formed in the plate adjacent its upper end. 
         [0019]    Preferably, the flexible and resilient plates are spaced apart by a predetermined distance selected to achieve a desired mat performance. In a preferred form the distance “L” between adjacent plates at the point of connection of the mat is about 200 mm or less in the case of square or rectangular trampolines and the same for the chord distance between adjacent points of connection for circular, elliptical or ovaloid trampolines. In the case of circular trampolines, the distance L is taken to be the chord distance between adjacent connection points and can be calculated according to the equation L=nD/n where n is the number of plates or connection points, D is the Diameter of the trampoline mat and n is the ratio of the circumference to its diameter and is usually rounded to 3.1428. 
         [0020]    Preferably, the frame comprises a plurality of interconnected tubular segments suitably sized for transport of the trampoline in knock-down form. Advantageously, such segments are connected in a manner so as to prevent relative rotational or pivoting movement therebetween. In that respect, it is preferred that the frame segments include keying means for keying them together against relative rotational movement. In a preferred form, the keying means is achieved by constructing the frame segments of square hollow section tube and having the and portions of adjacent segments drawn so that the end portion of one segment fits into the end portion of an adjacent segment. 
         [0021]    In another aspect, the invention resides broadly in a trampoline including: 
         [0022]    a frame adapted to rest on the ground or be mounted on spaced apart legs; 
         [0023]    a plurality of spaced apart flexible and resilient plates mounted to said frame against relative movement therebetween and extending upwards therefrom; 
         [0024]    a jumping mat operatively connected to said plates about its perimeter above said frame, said plates being arranged for movement inwards and outwards towards and away from the opposite side of said mat respectively, in response to a user jumping on said mat, and 
         [0025]    wherein said frame is a hollow section tube of rectangular cross section with a plurality of spaced apart slots therein and the lower end portions of said plates are mounted in respective slots. 
         [0026]    In another aspect, the invention resides broadly in the combination of a frame for a trampoline and a plurality of elongate flexible and resilient plates adapted to support a jumping mat connected thereto at their upper ends, the frame including a hollow section tube of rectangular cross section with a plurality of spaced apart slots therein and wherein the lower end portions of said plates are mounted in respective slots. 
         [0027]    Preferably, at least some of the plates include a foot or root portion at their lower ends, the foot including a toe portion adapted to engage an inside corner of the hollow section tube. It is also preferred that the foot or foot portion include stop means adapted to engage with the inside face of the upper wall of the tube to prevent the leaf spring escaping therefrom. In a preferred form, the foot is a steel angle bend secured to the lower end portion of the leaf spring. 
         [0028]    In such form, it is preferred that the slots be slightly wider than the thickness of the plate near the lower end so that the end portion can be fitted to the frame through the slot by firstly placing the toe portion into the slot and then rotating the leaf spring about the outer edge of the slot. 
         [0029]    In still yet another aspect, the invention resides broadly in a trampoline including: 
         [0030]    a frame forming a substantially continuous horizontal ring adapted to rest on the ground or above the ground on spaced apart legs; 
         [0031]    a plurality of spaced apart flexible and resilient plates mounted to said frame against undesired relative movement therebetween and extending upwardly therefrom; 
         [0032]    a jumping mat operatively connected to said plates about its perimeter above said frame, each of said plates being arranged for movement inwards and outwards towards and away from the opposite side of said mat respectively in response to a user jumping on said mat, and 
         [0033]    wherein said frame comprises a plurality of segments of hollow section tube with adjacent segments connected end to end by separate segment connectors adapted to engage therein. 
         [0034]    Preferably, said segment connectors are adapted to support the frame immediately above the ground (or other suitable foundation on which the trampoline is to be placed). For that purpose it is preferred that each segment connector include a frame support portion adapted to engage the ground and two opposed frame engagement portions extending sideways therefrom for engagement in the hollow of the opposed adjacent frame segments. In a particularly preferred form, the frame support portion is symmetrical about a vertical axis through the centre of the frame support portion. It is also preferred that the frame engagement portions include means for fastening the adjacent frame segments thereto. In a preferred form, such means include threaded bores adapted to screwthreadedly receive therein bolts extending through aligned holes formed in the adjacent frame segments. In a particularly preferred form, each frame engagement portion includes at least two vertically spaced threaded bores adjacent the outer ends thereof. In one embodiment in which the segment connector is formed from cast aluminium alloy, the bores are provided in inserts formed of a stronger metal such as steel which are fitted in suitable recesses provided in the cast alloy. However, in other embodiments where the connectors are made of cast iron or steel, the threaded borers can be formed directly therein. Advantageously, the threaded connectors provides for the bolts to extend through only one wall of the frame segments so that the bolt heads will be exposed on only the inner side of the frame. It is also preferred that the frame engagement portions have slots or recesses for accommodating therein the lower ends of the flexible and resilient plates adjacent the ends of the respective frame segments connected thereto. 
         [0035]    Preferably, said segment connectors include pole mounting means for mounting thereto poles adapted to support a safety net about the trampoline. In a preferred form, such pole mounting means includes a cavity in the segment connector adapted to slidably receive therein a net pole from above whereby a net pole can be pushed into the cavity from about so that it stands up from the frame. In a preferred form the cavity is arranged such that an elongate tubular net pole extends upwardly and slightly outwardly away from the jumping mat so that the safety net can be connected to the net pole above and outwardly beyond the mat. 
         [0036]    Preferably, said hollow section tube is of rectangular cross section with the major axis vertical and the minor axis horizontal with a plurality of spaced apart slots therein provided in the upper wall of the tube and the lower end portions of said plates mounted in respective ones of the slots. In such form of the invention it is preferred that the frame engagement portions be of a complementary cross section adapted to slide neatly into the end portions of the frame segments. 
         [0037]    In still yet another aspect, the invention resides broadly in a frame segment connector including: 
         [0038]    a frame support portion adapted to engage the ground; 
         [0039]    two opposed frame segment engagement portions extending sideways from said frame support portion for engagement in the hollow of opposed adjacent frame segments and including means for fastening adjacent frame segments thereto said means including threaded bores adapted to screwthreadedly receive therein bolts extending through aligned holes formed in the adjacent frame segments. 
         [0040]    Preferably, the frame segment connector is symmetrical about a vertical axis through the centre of the frame support portion. 
         [0041]    Preferably, each frame segment engagement portion includes at least two vertically spaced threaded bores adjacent the outer ends thereof. 
         [0042]    Preferably, the frame segment engagement portions have slots or recesses for accommodating therein the lower ends of the flexible and resilient plates adjacent the ends of the respective frame segments connected thereto. 
         [0043]    Preferably, the frame support portion has a cavity adapted to slidably receive therein a net pole from above. 
         [0044]    Terms such as “horizontal”, “vertical”, “upwards”, “downwards”, “above”, “below” and similar terms as used herein are for the purpose of describing the invention in its normal in-use orientation and are not intended to limit the invention to any particular orientation. 
         [0045]    The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0046]      FIG. 1  is a pictorial representation of a trampoline according to the invention; 
           [0047]      FIG. 2  is a pictorial representation of the trampoline of  FIG. 1  with the mat removed for clarity; 
           [0048]      FIG. 3  is a front elevation of the trampoline of  FIG. 1 ; 
           [0049]      FIG. 4  is a top plan of the trampoline of  FIG. 1 ; 
           [0050]      FIG. 5  is a bottom plan of the trampoline of  FIG. 1 ; 
           [0051]      FIG. 6  is a plan of the trampoline of  FIG. 1  with the net removed for clarity; 
           [0052]      FIG. 7  is a bottom plan of the trampoline of  FIG. 1  with net and legs removed; 
           [0053]      FIG. 8  is an elevation of the trampoline of  FIG. 1  with net and legs removed; 
           [0054]      FIG. 9  is a plan of a section of the edge of the mat; 
           [0055]      FIG. 10  is a pictorial representation of a leaf spring component of the trampoline of  FIG. 1 ; 
           [0056]      FIG. 11  is an end elevation of the leaf spring component of  FIG. 10 ; 
           [0057]      FIG. 12  is a front elevation of the leaf spring component of  FIG. 10 ; 
           [0058]      FIG. 13  is a rear elevation of the leaf spring component of  FIG. 10 ; 
           [0059]      FIG. 14  is a pictorial representation of another trampoline according to the invention resting on a floor with a safety enclosure fitted; 
           [0060]      FIG. 15  is a pictorial representation of the trampoline of  FIG. 14  tilted to show the underside; 
           [0061]      FIG. 16  is a front elevation of the trampoline of  FIG. 14 : 
           [0062]      FIG. 17  is a pictorial representation of the trampoline of  FIG. 14  with the safety not removed; 
           [0063]      FIG. 18  is a plan of the trampoline of  FIG. 14  with the safety net removed; 
           [0064]      FIG. 19  is a blown up view of a peripheral portion of the trampoline of  FIG. 14  with the safety net removed; 
           [0065]      FIG. 20  is a top plan of the trampoline of  FIG. 14  with the safety enclosure removed; 
           [0066]      FIG. 21  is a blown up top plan of a portion of the trampoline shown in  FIG. 20  as Detail A; 
           [0067]      FIG. 22  is a pictorial representation of the bottom frame of the trampoline of  FIG. 14 ; 
           [0068]      FIG. 23  is a blown up view of a portion of the trampoline shown in  FIG. 22  as Detail B; 
           [0069]      FIG. 24  is a plan of a segment of the bottom frame shown in  FIG. 22 ; 
           [0070]      FIG. 25  is a sectional representation of the segment shown in  FIG. 24  along Line  25 - 25 ; 
           [0071]      FIG. 26  is a pictorial representation of the segment shown in  FIG. 24 ; 
           [0072]      FIG. 27  is a pictorial representation of the mat connector of the trampoline of  FIG. 14 ; 
           [0073]      FIG. 28  is a plan of the mat connector shown in  FIG. 27 ; 
           [0074]      FIG. 29  is a sectional elevation of the mat connector shown in  FIG. 27  along line  29 - 29 ; 
           [0075]      FIG. 30  is a pictorial representation of the mat hook of the trampoline of  FIG. 14 ; 
           [0076]      FIG. 31  is a side elevation of the mat hook shown in  FIG. 30 ; 
           [0077]      FIG. 32  is a pictorial representation of the mat hook of  FIG. 30  and mat connector of  FIG. 27  connected together for operation from above; 
           [0078]      FIG. 33  is a pictorial representation of the mat hook of  FIG. 30  and mat connector of  FIG. 27  connected together for operation from below; 
           [0079]      FIG. 34  is a front elevation of the leaf spring components of the trampoline shown in  FIG. 14 ; 
           [0080]      FIG. 35  is a blown up view of the upper end of the leaf spring shown in  FIG. 34 ; 
           [0081]      FIG. 36  is a side elevation of the leaf spring component of  FIG. 12  along line  36 - 36 ; 
           [0082]      FIG. 37  is a blown up view of a portion of the mat connector component of the trampoline shown in  FIG. 14  and its connection to the leaf spring shown as Detail C in  FIG. 36 ; 
           [0083]      FIG. 38  is a blown up view of a portion of the mat connector component of the trampoline shown in  FIG. 14  and its connection to the leaf spring shown as Detail C in  FIG. 36  in a sectional pictorial view; 
           [0084]      FIG. 39  is a blown up view of a portion of the leaf spring shown in  FIG. 36  as Detail D; 
           [0085]      FIG. 40  is a blown up view of a portion of the leaf spring shown in  FIG. 34  and its connection to the bottom frame shown as Detail E in  FIG. 36 ; 
           [0086]      FIG. 41  is a pictorial representation of another trampoline according to the invention resting on a floor with a safety enclosure fitted; 
           [0087]      FIG. 42  is a blown up portion of part of the trampoline shown in  FIG. 41  as Detail F; 
           [0088]      FIG. 43  is a pictorial representation of the trampoline of  FIG. 41  with the safety enclosure and mat removed for Clarity; 
           [0089]      FIG. 44  is a front elevation of the trampoline of  FIG. 1  with the safety enclosure and mat removed for clarity; 
           [0090]      FIG. 45  is a sectional side elevation of the trampoline of  FIG. 41  with the safety enclosure and mat removed for clarity; 
           [0091]      FIG. 46  is a blown up portion of part of the trampoline shown in  FIG. 41  as Detail G; 
           [0092]      FIG. 47  is a pictorial representation of a segment of the bottom frame of the trampoline of  FIG. 41  with a leaf spring mounted thereto; 
           [0093]      FIG. 48  is a sectional end elevation of the segment of the bottom frame shown in  FIG. 7 ; 
           [0094]      FIG. 49  is a blown up portion of part of the segment shown in  FIG. 47  through the leaf spring marked as Detail H; 
           [0095]      FIG. 50  is a pictorial representation of another trampoline according to the invention resting on a floor with a safety enclosure fitted; 
           [0096]      FIG. 51  is a blown up drawing of part of the trampoline shown in  FIG. 50  as Detail J; 
           [0097]      FIG. 52  is a pictorial representation of one of the frame segment connector which connect the base frame segments of the trampoline of  FIG. 50  from the outside; 
           [0098]      FIG. 53  is a pictorial representation of the frame segment connector of  FIG. 50  from the inside; 
           [0099]      FIG. 54  is a plan of the connector of  FIG. 52 ; 
           [0100]      FIG. 55  is an outside elevation of the connector of  FIG. 52 : 
           [0101]      FIG. 56  is an inside elevation of the connector of  FIG. 52 ; 
           [0102]      FIG. 57  is a pictorial representation of the frame segment connector of rig.  52  disassembled; 
           [0103]      FIG. 58  is a bottom plan of the frame segment connector of  FIG. 52 ; and 
           [0104]      FIG. 59  is an end elevation of the frame segment connector of  FIG. 52 . 
       
    
    
     DETAILED DESCRIPTION 
       [0105]    The trampoline  10  illustrated in  FIG. 1  includes an elevated circular bottom, frame  11  constructed of 65 mm round steel tube which is supported on eight angularly spaced legs  12  each of which is connected to the frame by opposed leg mounts  13  and pairs of adjacent legs are connected by a horizontal member at their lower ends. Suitably, a jumping mat  14  is operatively connected to the frame  11  via sixteen equally angularly spaced leaf springs  21  which extend upwardly and curve outwardly from the frame. 
         [0106]    The leaf springs  21  are rigidly secured to the frame by three bolts  22  which pass through suitable bolt holes formed in the frame. As can be seen in  FIG. 11 , the upper end of the leaf spring is folded back on itself to form a saddle clamp  23  which wraps around a short steel tube  24  in which a segment of fibreglass rod  26  is fitted and secured therein by a suitable flexible adhesive as can be seen in  FIGS. 10 to 13 . 
         [0107]    As can be seen in  FIGS. 5 and 9 , the sixteen fibreglass segments  26  together form an outer disconnected ring  27  about the mat with the ends of adjacent segment being slightly spaced apart. In other embodiments, the segments are slidably connected by plastic sleeves which allow sufficient relative movement towards and away from other to accommodate changes in diameter of the disconnected ring while a user is jumping on the mat. 
         [0108]    A second disconnected ring  31  within ring  27  (previously described) is formed by another sixteen fibreglass rod segments  32  which are connected to the periphery of the mat  14  by wire hooks  33  in a manner similar to that in which the extension springs are connected to the mat in the known trampolines. The two rings are secured together by loop ties  34  formed of rubber or other suitable flexible and resilient material to form two generally concentric rings which at rest lie generally in the horizontal plane containing the mat. 
         [0109]    A safety net  41  extends fully about the net  14  as can be seen in  FIG. 1  and is secured to the mat at its lower edge  42  by circumferentially spaced “D” hooks which connect to the loops  33  provided at the periphery of the mat. The net is connected at its upper edge  46  to the upper end of circumferentially spaced posts  44 . Advantageously, the safety net has a vinyl plastic border strip  47  along its lower edge with circumferentially spaced slits  48  provided therein and respective D hooks pass through the slits so as to secure the net thereto. 
         [0110]    The posts  44  are formed of steel tube and a post is coupled to each leg mount by a pivot pin  51  for limited in and out pivoting movement relative to the mat about a horizontal axis against a leaf spring  52 . The net posts are connected to the net at their upper ends by a packet  53 . If desired, the safety net may be coupled to the posts intermediate the upper and lower edges by rubber straps or similar flexible and resilient ties and also may be connected to each other by a fibreglass ring of the same diameter as the mat. 
         [0111]    The trampoline  110  is similar to the trampoline  10  illustrated in  FIG. 1  in many respects and accordingly, the corresponding reference numbers will be used to reference corresponding components where possible except prefaced by a “1”. The trampoline  110  illustrated in  FIG. 14  includes a circular bottom frame  111  constructed of 65 mm round steel tube which is supported on eight short angularly spaced legs  112  each of which is connected to the frame by opposed leg mounts  113 . In this example, the legs are not connected in pairs as with the trampoline of  FIG. 1 . While the bottom frame in the embodiment shown is circular in cross section, other shapes may also be used, for example, the cross sectional shape shown in  FIG. 39  as  111   a . Suitably, a jumping mat  114  is operatively connected to the frame  111  via forty equally angularly spaced plate like leaf springs  121  which extend upwardly and curve inwardly from the frame. 
         [0112]    The leaf springs  121  pass through spaced apart slots  122  respectively which are formed in the bottom frame  111  and parallel to the curved longitudinal axis of the frame and are rigidly secured therein by virtue of a tight fit. The leaf springs are held in the slots by bolts or rivets  123  passing through the leaf springs immediately above and below the bottom frame respectively. However, if desired, the leaf springs could have a bend at their lower ends to prevent them lifting out of the slots under the jumping action of a user although it is believed that such an occurrence would be unlikely if not impossible. 
         [0113]    The mat  114  is connected at its periphery to the leaf springs  121  adjacent their upper ends by connector assemblies  131  as can be seen more clearly in  FIGS. 32 and 33 . Each connector assembly comprises a load bearing connector block  132  and a hook  133 . The connector block  132  is adapted to engage in a circumferential pocket  134  formed at the periphery of the mat in a manner suitable for carrying the tensile load of the stretched mat. The hook  133  is a twin ended loop hook with the loop  136  hooking to the connector block and the free ends  137  both hooking to the leaf spring in side by side relation through two spaced apart holes  138  in the leaf spring as can be seen more clearly in  FIG. 35 . 
         [0114]    The peripheral pocket is formed by folding the edge portion  114   a  of the mat under and stitching the folded portion to the underside of the mat  14  in known manner. Suitably, angularly spaced slots  139  are formed in the underside of the pocket to align with the leaf springs  121  respectively so that each leaf spring can extend into the pocket where it is connected to the mat via the hooks  133  and connector blocks  132 . 
         [0115]    As can be more clearly seen in  FIGS. 32 and 33 , the connector block is moulded from a plastics material and has a curved outer face  141  which is engaged by the mat and bears the tensile load of the mat thereagainst. A passage  142  is provided in the block and a recessed bridge  144  adjacent the passage forms a mount for attachment of the loop end  136  of the hook  133 . Suitably, the passage  142  is adapted to accommodate the end portion of the leaf spring therein thus protecting the mat and users of the trampoline from injury. 
         [0116]    A safety net  151  extends fully about the mat  114  as can be seen in  FIG. 14  and is secured to the mat at its lower edge  152  by circumferentially spaced “D” hooks which connect to the hooks  133  at the periphery of the mat. The net is connected at its upper edge  156  to a circular ring  155  of approximately the same diameter as the bottom frame and is supported by spaced apart posts  154  via clamps  158 . 
         [0117]    The posts  154  are formed of steel tube and the posts are slidably engaged in sleeves  161  which in turn are rigidly connected to the legs  112  thereby forming a rigid safety frame to which the safety net can be flexibly connected. If desired, the safety net may be coupled to the posts intermediate the upper and lower edges by rubber straps or similar flexible and resilient ties and also may be connected to each other by a fibreglass ring of the same diameter as the mat. 
         [0118]    As can be seen more clearly in  FIGS. 23 to 26 , the bottom frame comprises interconnected tubular segments  124  of generally circular cross section. However, the end portions of the segments are formed with a generally square cross section shown at  162  and have keying recesses  163  formed therein. Advantageously, the end portions are shaped to tightly engage in the square cross sectioned leg mounts  113  thereby inhibiting relative rotation between frame segments. As can be seen in  FIG. 23  adjacent frame segments are bolted to the leg mounts  113  by bolts  164 . 
         [0119]    The trampoline  210  illustrated in  FIG. 41  is also similar to the trampolines  10  and  110  illustrated in earlier drawings in many respects. Accordingly, the same reference numbers will be used to reference corresponding components as far as possible except prefaced by a “2”. 
         [0120]    The trampoline  210  also includes a circular bottom frame  211  comprising eight arcuate segments  212  as in the earlier drawings but in this embodiment the segments are constructed of rectangular hollow section steel tube. The segments are supported on eight short angularly spaced legs or feet  213 . Each leg  213  includes opposed outwardly extending stub tubes  214  which are suitably sized to receive thereover the end portions of tubular frame segments  215  which slide thereon and are secured by vertical bolts  216 . 
         [0121]    The bottom frame in this embodiment is rectangular in cross section comprising outside wall  212   a , bottom wall  212   b , inside wall  212   c  and bottom wall  212   d  with the short sides horizontal and the long sides vertical. However, square section tube would also be satisfactory and perhaps even polygonal shaped tubes. 
         [0122]    Suitably, a jumping mat  217  (hidden) is operatively connected to the bottom frame  11  via forty equally angularly spaced leaf springs  221  which extend upwardly and curve inwardly from the frame in much the same manner as for trampoline  110  illustrated in earlier drawings. Advantageously, spaced apart slots  218  are cut or punched in the upper wall  212   b  of the bottom frame for mounting the leaf springs thereto as will be described below. 
         [0123]    Each leaf spring comprises three laminated spring steel plates of equal thickness with three layers,  221   a ,  221   b  and  221   c  at the bottom end reducing to two layers,  221   a  and  221   b  in the mid-section and only one layer  221   a  nearer the top. At the bottom end, a foot  222  formed or unequal flange angle iron is welded to layer  221   c  so that its long flange  222   a  rests against the outer face of layer  221   c  and its short flange  222   b  is under the bottom end of the leaf spring providing a toe  222   c  which is arranged to engage the inside bottom corner  212   e  of the steel tube adjacent its outer wall  212   a  while the tip  222   d  of the long flange engages the inner face of the top wall  212   d  of the steel tube adjacent slot  218  thereby preventing the leaf spring from escaping from the slot when in operation because the tension applied by the mat to the upper end of the leaf spring holds the toe in engagement with the tube and that in turn holds the tip under the upper wall of the tube. 
         [0124]    A safety net  251  extends fully about the mat as can be seen in  FIG. 41  and is secured in the same manner as described in relation to trampoline  110  as shown in  FIG. 14 . 
         [0125]    The trampoline  310  illustrated in  FIG. 50  is similar to the trampolines  10 ,  110  and  210  previously described in many respects and accordingly the same reference numbers will be used to reference corresponding components where possible except prefaced by a “3”. The trampoline  310  includes a circular bottom frame  11  comprising eight arcuate segments  312  constructed of rectangular hollow section steel tube which are connected to each other by cast alloy segment connectors  313  each of which has a foot portion arranged to support the connector and the frame immediately above the ground as will be described in more detail later. Each connector  313  includes opposed outwardly extending arm like members  314  which are suitably sized to receive thereover the end portions of tubular frame segments  312  which slide thereon and are secured by pairs of vertically spaced apart horizontal bolts  316  which extend radially outwards. 
         [0126]    The bottom frame in the embodiment shown is rectangular in cross section comprising outside wall  312   a , bottom wall  312   b , inside wall  312   c  (not visible) and bottom wall  312   d  with the short sides horizontal and the long sides vertical. A jumping mat  317  is operatively connected to the bottom frame  311  via fifty-four equally angularly spaced leaf springs  321  which extend upwardly and curve inwardly from the frame  311 , each leaf spring being securely engaged in respective slots provided in the upper wall of the bottom frame in much the same manner as for the trampoline  210  illustrated in  FIG. 41  and a safety net  351  extends fully about the mat in the same manner and is secured to the mat at its lower edge  352  by circumferentially spaced “D” hooks which connect to the hooks  333  at the periphery of the mat. The net is connected at its upper edge  356  to a circular ring  355  of approximately the same diameter as the bottom frame and is supported by spaced apart posts  354 . 
         [0127]    In this embodiment, the segment connectors  313  are formed of cast aluminium alloy but in other embodiments they are formed of cast iron or cast steel but any other suitable material capable of withstanding the torsion applied thereto by the leaf springs  321  could be used if desired. Suitably, each leg connector has a centre portion  371  which is shaped to provide a foot  372  having a bottom face  372   a  adapted to rest on the ground. Advantageously, the bottom face is curved slightly in the in-use radial direction (shown as arrows A and B) to accommodate slight twisting of the frame segments  312  during operation of the jumping mat. 
         [0128]    As can be seen more clearly in  FIG. 52 , the connector  313  has a solid front wall  373  having a front face  373   a  and a rear face  373   b  from which a plurality of interconnected ribs or webs  375  extend rearwards (radially inwards in use) to terminate in an open face  375   a  the centre portion of which is closed by a cast alloy clip on cover  374 . 
         [0129]    Advantageously, an elongate cavity  376  of generally elliptical cross section is provided in the centre portion  371  for receiving therein the lower end portion of a safety net pole  354 . Suitably, a grub screw is screwthreadedly mounted in the webbed centre portion and arranged to engage with the pole to secure it in the cavity and is covered from view by the clip-on cover  374 . In order to prevent accumulation of water in the cavity, the passage is drained via an opening  375  formed in the rib on which the pole rests and a flexible plastics cover  376   a  is provided to substantially close the gap about the pole to inhibit ingress of rain. Suitably, the ribbed open face of the two opposed arms  314  are covered by the adjacent frame segments when secured in position. 
         [0130]    A recess  377  is formed in each arm for accommodating the bottom end portion of a leaf spring  321  which extends through the slot  318  formed in the upper wall  312   b  of the adjacent frame segment as described in relation to trampoline  210  and into the recess slot  377 . Suitably, the recess  377  allows for a loose fit so that the leaf spring can be fitted to its desired position. 
         [0131]    The frame segment on each side of the connector is secured to the connector by two bolts  316  as previously mentioned with each bolt being screwed into a threaded bush  381  which is tapered and adapted to engage in a complementary tapered bore  382 . 
         [0132]    Advantageously, the connector  313  provides an efficient and effective means of connecting frame segments so as to inhibit undesirable twisting while at the same time providing a suitable mount for the safety net. The connector also provides a means of cost effectively connecting shorter segments with a foot member so that twisting of frame segments can be reduced. 
         [0133]    While the invention has been described in detail in respect of a circular trampoline base frame, it will be appreciated that it could be used for trampolines of other shapes such as ovaloid, elliptical, polygonal particularly square and rectangular 
         [0134]    The foregoing description has been given by way of illustrative example of the invention and many modifications and variations which will be apparent to persons skilled in the art may be made without departing from the spirit and scope of the invention as defined by the appended claim.

Technology Classification (CPC): 0