Recreational structure using a sleeve-joint coupling

A recreational structure, such as a trampoline frame, can be quickly and reliably assembled using a sleeve-joint coupling having a “T” configuration. A first arm member and an aperture that is formed in the sleeve-joint coupling are disposed in an opposite relationship. A second arm member and a third arm member are disposed in an opposite relationship with each other. The first arm member receives one end of a vertical frame member of the recreational structure, while the aperture receives one end of a vertical pole member of, for example, a safety enclosure. The second and third arm members each receive one end of a horizontal frame member of the recreational structure. The vertical pole member extends through the sleeve-joint coupling into an inner portion of the vertical frame member received by the first arm of the sleeve-joint coupling.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to recreational structures. More particularly, the present invention relates to a frame arrangement for a recreational structure, such as a trampoline, that uses a sleeve-joint coupling.

2. Description of the Related Art

Recreational structures having frames, such as trampolines, are well-known. For example, a trampoline has a horizontal frame to which a rebounding surface is attached and a plurality of vertical frame members, or legs, that support the horizontal frame and rebounding surface above the ground. While the horizontal and vertical frame portions of a trampoline could be fabricated to be one unitary structure, such a unitary structure is cumbersome when the trampoline frame is transported to a place where the trampoline is used. Accordingly, trampoline frames are typically formed from a plurality of pieces that are fastened together at the time a trampoline is assembled.

A desirable characteristic for all trampoline frames formed from a plurality of pieces is that the various pieces are attached or joined to each other using a technique that is simple, quick to assemble and is reliable.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a technique for joining structural components of a recreational structure, such as a trampoline, that is simple, quick to assemble and is reliable.

The advantages of the present invention are provided by a recreational structure frame system that includes a plurality of horizontal frame members, at least one vertical frame member, at least one vertical pole member, and at least one sleeve-joint coupling. Each horizontal frame member has two ends. Similarly, each vertical frame member has two ends, and each vertical pole member has two ends. In one exemplary embodiment, at least one sleeve-joint coupling has first, second and third arm members arranged to substantially form a T configuration and an aperture that is formed in the sleeve-joint coupling. That is, the first arm member and the aperture are disposed in an opposite relationship with respect to each other, and the second arm member and the third arm member are disposed in an opposite relationship with each other. In another exemplary embodiment, at least one sleeve-joint coupling includes a side sleeve member having the aperture. The first arm member receives one end of a vertical frame member. The aperture receives one end of a vertical pole member. The second and third arm members each receive one end of a horizontal frame member. The vertical pole member received by the aperture extends through the sleeve-joint coupling into an inner portion of the vertical frame member received by the first arm of the sleeve-joint coupling.

The vertical pole member can be part of, for example, a safety enclosure, in which case the safety enclosure can include a plurality of vertical pole members, such that each vertical pole member is received into the aperture of a sleeve-joint coupling. A plurality of horizontal support members can be coupled to two adjacent vertical pole members, thereby forming the safety enclosure. In one exemplary embodiment, the vertical pole member is configured to substantially form an arch.

One exemplary embodiment of a sleeve-joint coupling according to the present invention includes a fourth arm member, in which case the aperture is disposed at an end of the fourth arm member. A tension member can be coupled between adjacent sleeve-joint couplings that applies a force to the adjacent sleeve-joint couplings and forces the adjacent sleeve-joint couplings toward each other.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1depicts a perspective view of an exemplary trampoline100having an exemplary safety enclosure101. Trampoline100includes a rebounding surface102and a frame structure having vertical frame members103and a circular frame that can be formed from a plurality of circular frame members104. Vertical frame members103and circular frame members104are typically made from hollow metal tubing having sufficient strength to bear the stresses and loads that are associated with trampolines. Safety enclosure101includes a frame structure having vertical pole members105and horizontal support members106. A horizontal support member106is connected between adjacent vertical pole members in a substantially inflexible manner. A structural member that is suitable for both vertical pole members105and horizontal support members106is disclosed by U.S. Pat. No. 6,450,187 B1 to Lin et al., which is incorporated by reference herein.

Complete details of trampoline100and safety enclosure101are not shown inFIG. 1for simplicity. For example, safety enclosure includes a mesh- or netting-type of material that extends between adjacent vertical pole members105and between horizontal frame members106and circular frame member104that together with circular frame104, vertical pole members105and horizontal support members106operate as a fence around rebounding surface102in order to keep a user on trampoline100and reduce the risk of injury to the user.

According to the present invention, vertical pole members105of safety enclosure101attach to the frame structure of trampoline100using a plurality of sleeve-joint couplings, of which one is indicated at A inFIG. 1.FIGS. 2A-2DandFIG. 3show details of a first exemplary embodiment of a sleeve-joint coupling according to the present invention. In particular,FIGS. 2A-2Crespectively show a side view, a top view and an end view of the first exemplary embodiment of a sleeve-joint coupling200for a trampoline frame according to the present invention.FIG. 2Dshows a perspective view of sleeve-joint coupling200. Sleeve joint coupling200is generally shaped as a “T” and includes three arm members201-203, each having a generally square cross-sectional shape. Each arm member201-203receives a trampoline frame member (not shown inFIGS. 2A-2C) of similar cross-sectional shape into an opening204(FIGS. 2C and 2D). Sleeve joint coupling200includes an opening205, shown inFIG. 2B, that receives a safety enclosure vertical pole member (not shown inFIGS. 2A-2C) having a generally square cross-sectional member.

FIG. 3depicts View A, shown inFIG. 1, in greater detail. InFIG. 3, sleeve-joint coupling200couples circular frame member104A to circular frame member104B and to vertical frame member103. Circular frame members104A and104B are secured to sleeve-joint coupling200using, for example, pins301and cotter rings302(not shown inFIGS. 2A-2D). Alternatively, circular frame members104A and104B can be secured to sleeve-joint coupling200using sheet metal screws, and/or bolts and nuts. As yet another alternative, the inner surface of each arm member of sleeve-joint coupling can be threaded to engage complementary threading on each end of a circular frame member104and on one end of a vertical frame member103. Additionally, a threaded connection between sleeve-joint coupling200and a frame member can be secured using a pin and cotter ring arrangement, a sheet metal screw and/or a bolt and nut.

Vertical pole member105of safety enclosure101is inserted into opening205(FIGS. 3B and 3D) and extends through sleeve-joint coupling200into vertical frame member103a distance that is sufficient to distribute any shearing and/or torquing forces that may be imparted to vertical pole member105along the inside of vertical frame member103so that vertical frame member103does not fail. Vertical pole member105can be secured in vertical frame member103using, for example, a pin301and a cotter ring (not shown). Alternatively, vertical pole member105is secured in vertical frame member103using a sheet metal screw and/or a bolt and nut.

FIGS. 4A-4Crespectively show a side view, a top view and an end view of a second exemplary embodiment of a sleeve-joint coupling400for a trampoline frame according to the present invention. Sleeve-joint coupling400is generally shaped as a “T” and includes three arm members401-403, each having a generally round cross-sectional shape. Each arm member401-403receives a trampoline frame member (not shown inFIGS. 4A-4C) of similar cross-sectional shape into an opening404(FIG. 4C). Sleeve-joint coupling400includes an opening405, shown inFIG. 4B, that receives a safety enclosure vertical pole member (not shown inFIGS. 4A-4C) having a generally round cross-sectional member.

FIGS. 5A-5Crespectively show a side view, a top view and an end view of a third exemplary embodiment of a sleeve-joint coupling500for a trampoline frame according to the present invention. Sleeve-joint coupling500is generally shaped as a “T” and includes three arm members501-503, each having a generally oval cross-sectional shape. Each arm member501-503receives a trampoline frame member (not shown inFIGS. 5A-5C) of similar cross-sectional shape into an opening504(FIG. 5C). Sleeve-joint coupling500includes an opening505, shown inFIG. 5B, that receives a safety enclosure vertical pole member (not shown inFIGS. 5A-5C) having a generally oval cross-sectional member.

FIGS. 6A-6Crespectively show a side view, a top view and an end view of a fourth exemplary embodiment of a sleeve-joint coupling600for a trampoline frame according to the present invention. Sleeve-joint coupling600is generally shaped as a “T” and includes three arm members601-603, each having a generally triangular cross-sectional shape. Each arm member601-603receives a trampoline frame member (not shown inFIGS. 6A-6C) of similar cross-sectional shape into an opening604(FIG. 6C). Sleeve-joint coupling600includes an opening605, shown inFIG. 6B, that receives a safety enclosure vertical pole member (not shown inFIGS. 6A-6C) having a generally triangular cross-sectional member.

FIGS. 7A and 7Brespectively show a side view and a top view of a fifth exemplary embodiment of a sleeve-joint coupling700for a trampoline frame according to the present invention. Sleeve-joint coupling700is generally shaped as an “X” or a “+” and includes four arm members701-704, each having a generally square cross-sectional shape. Each arm member701-704receives a trampoline frame member (not shown inFIGS. 7A and 7B) of similar cross-sectional shape into an opening705, of which only one opening705is shown (FIG. 7B). Each opening705receives a safety enclosure vertical frame member103, a circular frame member104or a vertical pole member105(none of which are shown inFIGS. 7A and 7B) having a generally square cross-sectional member. It should be understood that sleeve-joint coupling700can have an alternative cross-sectional shape, such as any of the exemplary cross-sectional shapes described herein, and a mating vertical frame member, circular frame member and vertical pole member would have a corresponding cross-sectional shape.

FIGS. 8A-8Crespectively show a side view, a top view and an end view of a sixth exemplary embodiment of a sleeve-joint coupling800for a trampoline frame according to the present invention. Sleeve-joint coupling800is generally shaped as a “T” and includes three arm members801-803, each having a generally round cross-sectional shape. Sleeve-joint coupling800also includes a side-sleeve member804having an aperture805, configured as a blind hole, that receives a safety enclosure vertical pole member (not shown inFIGS. 8A-8C) having a generally round cross-sectional member. Side-sleeve member804has sufficient length and strength to allow a safety enclosure vertical pole to extend into side sleeve member804so that the vertical pole would not come out during use. Each arm member801-803receives a trampoline frame member (also not shown inFIGS. 8A-8C) of similar cross-sectional shape into an opening806(FIG. 8C). In an alternative embodiment, aperture805could be configured to allow a safety enclosure vertical pole to extend through the length of the side-sleeve member804to the ground or to another device that fastens the vertical pole to the corresponding frame member103. In yet another alternative embodiment, side sleeve member804could have a slot that extends from at least one end of side-sleeve member804toward the other end of side-sleeve member804such that aperture805is not completely enclosed. It should be understood that the slot could extend part of or the entire length of side-sleeve member804.

FIG. 9depicts a top cutaway view of the first exemplary embodiment of a sleeve-joint coupling200according to the present invention. Two circular frame members104A and104B are shown inFIG. 9respectively engaging arm members201and202of sleeve-joint coupling200. A vertical pole member105of a safety enclosure is also shown. A tension member901, such as a strap of webbing, a wire or a cable, is shown threaded through circular frame members104A and104B and sleeve-joint coupling200, in addition the other circular frame members and sleeve-joint coupling forming a trampoline frame. Tension member901is fastened in a well-known manner to a hook assembly902that engages a loop903of a buckle assembly904that is accessible through a hole (not shown) in circular frame member104B. Buckle assembly904has two positions; an open position that allows hook assembly902and loop903to be conveniently engaged, and a closed assembly that places tension member901under tension. When tension member901is under tension, each sleeve-joint coupling200that tension member901passes through is urged toward the center of the trampoline frame structure, thereby making the joints of frame structure even more reliable. Alternatively, a plurality of tension members can be used to form a line of continuous tension around a trampoline frame instead of a single tension member, as depicted inFIG. 9. As yet another alternative, tension member901could be attached to the outside of sleeve-joint coupling200, such as through a loop fastened to the outside of sleeve-joint coupling200. Still another alternative provides that a turn-buckle arrangement is used for placing tension on tension member901.

While exemplary trampoline100shown inFIG. 1is depicted as being round, it should be understood that the present invention could be used with a trampoline and safety enclosure having a different shape, such as square, rectangular or oval. Additionally, the sleeve-joint coupling of the present invention can be made from any suitable material that has sufficient strength to bear the loads and stresses that are associated with trampolines, such as metals and plastics. Further, while the sleeve-joint coupling of the present invention has been described in terms of vertical frame members and circular frame members fitting into the sleeve-joint coupling, it should be understood that the sleeve-joint coupling of the present invention can be configured so that one or all of the arm members of the sleeve-joint coupling fit into vertical frame members and circular frame members of the trampoline frame. Further still, while the sleeve-joint coupling of the present invention has been described as having several exemplary cross-sectional shapes, it should be understood that a sleeve-joint coupling according to the present invention could have any cross-sectional shape or have arm members having different cross-sectional shapes. As yet another alternative, the sleeve-joint coupling of the present invention could be formed to be part of a vertical frame member. As still another alternative, the sleeve-joint coupling of the present invention could be configured to substantially form a “T”.

While the vertical pole members105of safety enclosure101has been described as extending into vertical frame members103, it should be understood that at least one or more vertical pole member105of safety enclosure101could extend to the ground along the outside of a vertical frame member103, in which case such a vertical pole member would be attached to the corresponding vertical frame member at a minimum of two places, such as by using a sleeve-joint coupling similar to that shown inFIGS. 8A-8Cand, for example, a tie-wrap device near the bottom of a vertical frame member103.

As yet another alternative embodiment, a safety enclosure vertical pole member105could be configured to form an arch (105aof trampoline100ainFIG. 10), or an arc shape, between two frame members103. The two frame members103could be adjacent or could be separated by one or more other frame members103. A horizontal support member would then be connected between adjacent peaks of an arch in a substantially inflexible manner.