# Patent

## Title
Trampolines

## 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.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a National Phase of PCT/AU2012/000651, filed 7 Jun., 2012 which claims the priority from 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.
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.
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.
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.
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'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.
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.
With the foregoing in view, the invention in one aspect resides broadly in 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.
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.
In another aspect, the invention resides broadly in 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;
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.
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.
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.
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.
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.
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.
In another aspect, the invention resides broadly in a trampoline including:
a frame adapted to rest on the ground or be mounted on spaced apart legs;
a plurality of spaced apart flexible and resilient plates mounted to said frame against relative movement therebetween and extending upwards therefrom;
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
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.
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.
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.
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.
In still yet another aspect, the invention resides broadly in a trampoline including:
a frame forming a substantially continuous horizontal ring adapted to rest on the ground or above the ground on spaced apart legs;
a plurality of spaced apart flexible and resilient plates mounted to said frame against undesired relative movement therebetween and extending upwardly therefrom;
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
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.
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.
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.
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.
In still yet another aspect, the invention resides broadly in a frame segment connector including:
a frame support portion adapted to engage the ground;
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.
Preferably, the frame segment connector is symmetrical about a vertical axis through the centre of the frame support portion.
Preferably, each frame segment engagement portion includes at least two vertically spaced threaded bores adjacent the outer ends thereof.
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.
Preferably, the frame support portion has a cavity adapted to slidably receive therein a net pole from above.
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.



In order that the invention may be more readily understood and put into practice, reference will now be made to the accompanying drawings, wherein:
FIG. 1 is a pictorial representation of a trampoline according to the invention;
FIG. 2 is a pictorial representation of the trampoline of FIG. 1 with the mat removed for clarity;
FIG. 3 is a front elevation of the trampoline of FIG. 1;
FIG. 4 is a top plan of the trampoline of FIG. 1;
FIG. 5 is a bottom plan of the trampoline of FIG. 1;
FIG. 6 is a plan of the trampoline of FIG. 1 with the net removed for clarity;
FIG. 7 is a bottom plan of the trampoline of FIG. 1 with net and legs removed;
FIG. 8 is an elevation of the trampoline of FIG. 1 with net and legs removed;
FIG. 9 is a plan of a section of the edge of the mat;
FIG. 10 is a pictorial representation of a leaf spring component of the trampoline of FIG. 1;
FIG. 11 is an end elevation of the leaf spring component of FIG. 10;
FIG. 12 is a front elevation of the leaf spring component of FIG. 10;
FIG. 13 is a rear elevation of the leaf spring component of FIG. 10;
FIG. 14 is a pictorial representation of another trampoline according to the invention resting on a floor with a safety enclosure fitted;
FIG. 15 is a pictorial representation of the trampoline of FIG. 14 tilted to show the underside;
FIG. 16 is a front elevation of the trampoline of FIG. 14:
FIG. 17 is a pictorial representation of the trampoline of FIG. 14 with the safety not removed;
FIG. 18 is a plan of the trampoline of FIG. 14 with the safety net removed;
FIG. 19 is a blown up view of a peripheral portion of the trampoline of FIG. 14 with the safety net removed;
FIG. 20 is a top plan of the trampoline of FIG. 14 with the safety enclosure removed;
FIG. 21 is a blown up top plan of a portion of the trampoline shown in FIG. 20 as Detail A;
FIG. 22 is a pictorial representation of the bottom frame of the trampoline of FIG. 14;
FIG. 23 is a blown up view of a portion of the trampoline shown in FIG. 22 as Detail B;
FIG. 24 is a plan of a segment of the bottom frame shown in FIG. 22;
FIG. 25 is a sectional representation of the segment shown in FIG. 24 along Line 25-25;
FIG. 26 is a pictorial representation of the segment shown in FIG. 24;
FIG. 27 is a pictorial representation of the mat connector of the trampoline of FIG. 14;
FIG. 28 is a plan of the mat connector shown in FIG. 27;
FIG. 29 is a sectional elevation of the mat connector shown in FIG. 27 along line 29-29;
FIG. 30 is a pictorial representation of the mat hook of the trampoline of FIG. 14;
FIG. 31 is a side elevation of the mat hook shown in FIG. 30;
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;
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;
FIG. 34 is a front elevation of the leaf spring components of the trampoline shown in FIG. 14;
FIG. 35 is a blown up view of the upper end of the leaf spring shown in FIG. 34;
FIG. 36 is a side elevation of the leaf spring component of FIG. 12 along line 36-36;
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;
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;
FIG. 39 is a blown up view of a portion of the leaf spring shown in FIG. 36 as Detail D;
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;
FIG. 41 is a pictorial representation of another trampoline according to the invention resting on a floor with a safety enclosure fitted;
FIG. 42 is a blown up portion of part of the trampoline shown in FIG. 41 as Detail F;
FIG. 43 is a pictorial representation of the trampoline of FIG. 41 with the safety enclosure and mat removed for Clarity;
FIG. 44 is a front elevation of the trampoline of FIG. 1 with the safety enclosure and mat removed for clarity;
FIG. 45 is a sectional side elevation of the trampoline of FIG. 41 with the safety enclosure and mat removed for clarity;
FIG. 46 is a blown up portion of part of the trampoline shown in FIG. 41 as Detail G;
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;
FIG. 48 is a sectional end elevation of the segment of the bottom frame shown in FIG. 7;
FIG. 49 is a blown up portion of part of the segment shown in FIG. 47 through the leaf spring marked as Detail H;
FIG. 50 is a pictorial representation of another trampoline according to the invention resting on a floor with a safety enclosure fitted;
FIG. 51 is a blown up drawing of part of the trampoline shown in FIG. 50 as Detail J;
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;
FIG. 53 is a pictorial representation of the frame segment connector of FIG. 50 from the inside;
FIG. 54 is a plan of the connector of FIG. 52;
FIG. 55 is an outside elevation of the connector of FIG. 52:
FIG. 56 is an inside elevation of the connector of FIG. 52;
FIG. 57 is a pictorial representation of the frame segment connector of rig. 52 disassembled;
FIG. 58 is a bottom plan of the frame segment connector of FIG. 52; and
FIG. 59 is an end elevation of the frame segment connector of FIG. 52.



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.
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.
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.
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.
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.
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.
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 111a. 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.
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.
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.
The peripheral pocket is formed by folding the edge portion 114a 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.
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.
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.
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.
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.
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”.
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.
The bottom frame in this embodiment is rectangular in cross section comprising outside wall 212a, bottom wall 212b, inside wall 212c and bottom wall 212d with the short sides horizontal and the long sides vertical. However, square section tube would also be satisfactory and perhaps even polygonal shaped tubes.
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 212b of the bottom frame for mounting the leaf springs thereto as will be described below.
Each leaf spring comprises three laminated spring steel plates of equal thickness with three layers, 221a, 221b and 221c at the bottom end reducing to two layers, 221a and 221b in the mid-section and only one layer 221a nearer the top. At the bottom end, a foot 222 formed or unequal flange angle iron is welded to layer 221c so that its long flange 222a rests against the outer face of layer 221c and its short flange 222b is under the bottom end of the leaf spring providing a toe 222c which is arranged to engage the inside bottom corner 212e of the steel tube adjacent its outer wall 212a while the tip 222d of the long flange engages the inner face of the top wall 212d 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.
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.
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.
The bottom frame in the embodiment shown is rectangular in cross section comprising outside wall 312a, bottom wall 312b, inside wall 312c (not visible) and bottom wall 312d 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.
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 372a 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.
As can be seen more clearly in FIG. 52, the connector 313 has a solid front wall 373 having a front face 373a and a rear face 373b from which a plurality of interconnected ribs or webs 375 extend rearwards (radially inwards in use) to terminate in an open face 375a the centre portion of which is closed by a cast alloy clip on cover 374.
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 376a 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.
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 312b 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.
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.
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.
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.
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.

## Claims

1. 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 each having an upper free end and a lower free end and being releasably connected to said frame at or adjacent their respective lower free ends against relative movement between said flexible and resilient plates and said frame, said plates extending upwards from their lower free ends; and
a jumping mat extending between said spaced apart flexible and resilient plates and being operatively connected at or adjacent its periphery to said flexible and resilient plates at or adjacent their upper ends for movement therewith upon a person jumping on said mat.

2. The trampoline according to claim 1 wherein said flexible and resilient plates extend upwards from their lower free ends and inwards or outwards towards their upper free ends.

3. The trampoline according to claim 1 wherein said flexible and resilient plates are arranged for flexing movement inwards and outwards towards and away from the opposite side of said mat in response to a user jumping on said mat.

4. The trampoline according to claim 3 wherein said flexible and resilient plates have a longitudinal axis and are selected such that they flex inwards and outwards whereby said longitudinal axis travels generally in only one plane.

5. The trampoline according to claim 1 wherein each flexible and resilient plate includes a plurality of elongate layers of spring steel over a substantial portion of its length.

6. The trampoline according to claim 1 wherein each of said spaced apart flexible and resilient plates is connected to said frame by engaging in spaced apart slots formed in said frame.

7. The trampoline according to claim 1 wherein said mat is connected to said spaced apart flexible and resilient plates adjacent their upper free ends by connector assemblies incorporating a hook and a load bearing fitting mounted in a pocket formed in said mat adjacent its periphery.

8. The trampoline according to claim 7 wherein said hooks are connected at one end to said mat via said load bearing fitting and at the other end to said flexible and resilient plates via one or more openings formed in each of said plates adjacent their upper free ends.

9. The trampoline according to claim 1 wherein said flexible and resilient plates are spaced apart by a predetermined distance selected to achieve a desired mat performance.

10. The trampoline according to claim 9 wherein said predetermined distance is about 200 mm or less.

11. The trampoline according to claim 1 wherein said frame includes a hollow bottom frame member (preferably of hollow rectangular cross section) having a plurality of spaced apart slots therein and the lower free end portions of said flexible and resilient plates are mounted in respective ones of said slots.

12. The trampoline according to claim 11 wherein at least some of said flexible and resilient plates each includes a foot or foot portion at or adjacent its lower end and each said foot includes a toe portion adapted to engage an inside corner of said bottom frame member.

13. The trampoline according to claim 12 wherein said bottom frame member includes an upper wall having an inside face and said flexible and resilient plates each include stop means adapted to engage with the inside face of said upper wall to prevent them escaping therefrom.

14. The trampoline according to claim 12 wherein said stop means is part of said foot or foot portion.

15. The trampoline according to claim 14 wherein said foot or foot portion includes an angle bend.

16. The trampoline according to claim 11 wherein the width of said slots is slightly greater than the thickness of said flexible and resilient plates near their lower ends so that their end portions can be fitted in the slot by firstly placing the toe portion into the slot and then rotating (or pivoting) the flexible and resilient plate about the outer edge of the slot.

17. The trampoline according to claim 2 wherein said flexible and resilient plates extend upwards from their lower free ends and inwards towards their upper free ends.

18. The trampoline according to claim 2 wherein said flexible and resilient plates extend upwards from their lower free ends and outwards towards their upper free ends.

19. In combination, a frame for a trampoline and a plurality of elongate flexible and resilient plates adapted to support a jumping mat connected at their upper ends, the frame including a hollow tube of rectangular cross section with a plurality of spaced apart slots therein and wherein the lower end portions of said flexible and resilient plates are mounted in respective ones of said plurality of spaced apart slots.

20. A trampoline including:
a frame forming a substantially continuous horizontal ring adapted to rest on the ground or above the ground on spaced apart legs;
a plurality of spaced apart flexible and resilient plates each having an upper free end and a lower free end and being connected to said frame at or adjacent their lower free ends against undesired relative to said frame each of said flexible and resilient plates extending upwards from their lower free ends;
a jumping mat operatively connected to said flexible and resilient plates about its perimeter above said frame, each of said flexible and resilient 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 wherein said frame includes a plurality of segments of hollow section tube with adjacent segments connected end to end by separate segment connectors adapted to engage with the ends of adjacent segments.

21. The trampoline according to claim 20 wherein said segment connectors are adapted to support said frame immediately above the ground or other foundation on which the trampoline is to be placed.

22. The trampoline according to claim 21 wherein each segment connector includes 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.

23. The trampoline according to claim 22 wherein said frame support portion is symmetrical about a vertical axis through the centre of said frame support portion.

24. The trampoline according to claim 22 or wherein said frame engagement portions include means for fastening the adjacent frame segments thereto.

25. The trampoline according to claim 24 wherein said means includes threaded bores adapted to screwthreadedly receive therein bolts extending through aligned holes formed in the adjacent frame segments.

26. The trampoline according to claim 20 wherein said segment connectors include pole mounting means for mounting thereto poles adapted to support a safety net about said jumping mat.

27. The trampoline according to claim 26 wherein said pole mounting means includes a cavity adapted to slidably receive therein a pole whereby the pole can be pushed into the cavity from above so as to stand up from said frame.

28. The trampoline according to claim 27 wherein said cavity is arranged such that an elongate tubular pole fitted therein extends upwardly and slightly outwardly away from said jumping mat whereby a safety net can be connected to the net pole above and outwardly beyond said jumping mat.

29. The trampoline according to claim 22 wherein said frame engagement portions are adapted to slidingly receive thereover a tube of rectangular hollow section.

30. The trampoline according to claim 1 including a flexible and resilient rod extending about the periphery of said jumping mat and wherein said mat is operatively connected to said flexible and resilient plates via said rod for movement with said mat and said flexible and resilient plates.

31. The trampoline according to claim 30 wherein said rod is a hollow rod.

32. The trampoline according to claim 30 wherein said rod is comprised of a plurality of connected segments.

33. The trampoline according to claim 30 wherein said rod is in the form of disconnected segments.

34. The trampoline according to claim 32 wherein said segments extend equidistant on opposite sides of said flexible and resilient plates.

35. The trampoline according to claim 32 wherein said segments are connected for relative movement between adjacent segments as said mat moves up and down.

36. The trampoline according to claim 30 wherein said rod is a first rod and said jumping mat is operatively connected to said flexible and resilient plates by said first rod and a second rod also extending about the periphery of said mat, said second rod being connected to said mat at a plurality of predetermined positions along its length and said second rod being connected to said first rod at a plurality of predetermined positions along its length.

37. The trampoline according to claim 36 wherein said first and second rods are connected so as to allow limited relative movement therebetween.