WO2006055885A1

WO2006055885A1 - Trampoline with adjustable spring tension

Info

Publication number: WO2006055885A1
Application number: PCT/US2005/042085
Authority: WO
Inventors: Mark W. Publicover
Original assignee: Publicover Mark W
Priority date: 2004-11-19
Filing date: 2005-11-18
Publication date: 2006-05-26
Also published as: US20060116242A1

Abstract

Springs or other elastic connectors used to support a bed within the frame of a trampoline or the like are attached using methods that permit the adjustment and/or a systematic variation of the tension (or the travel distance required to reach limit of elasticity) between adjacent (or sets of adjacent) springs. These spring attachment methods adjust the energy absorption capacity of the trampoline bed, as well as increase the time it takes a given trampoline to absorb a given amount of energy, increasing the shock absorption time and thereby reducing the likelihood of an injury.

Description

Specification

TRAMPOLINE WITH ADJUSTABLE SPRING

TENSION

Cross Reference to Related Applications

The present application claims priority to the U.S. provisional application for a "Trampoline with adjustable spring tension" filed on November 19, 2004, having serial number 60/629,652, which is incorporated herein by reference.

The present application also claims priority to the U.S. non-provisional application for a "Trampoline with adjustable spring tension" filed on November 17, 2005, having Attorney Docket # 130.18NP, which is incorporated herein by reference.

Background of Invention tOOOI ] The present invention relates to improvements in trampoline, and in particular, the present invention concerns jumping surfaces used with trampolines to protect trampoline users from injury, and to provide new uses for trampolines.

[0002] In the past, trampolines have been used for a variety of athletic and recreational purposes. However, thousands of injuries have resulted when persons jumping on a trampoline have landed on the rebounding surface while in an awkward or incorrect body position. These "on-bed" injuries, according to some medical studies, represent the majority of trampoline-related emergency room visits. The U.S. Consumer Products Safety Commission (CPSC) reports that in 1999 approximately 110,000 people were treated in emergency rooms for trampoline related injuries. Even though this number is half that of play structure/swing set injuries, some in the medical community have called for a ban on the sale of backyard trampolines. The CPSC and the AAOS have taken a more responsible and measured approach to problem. Recognizing that other outdoor activities that are more injurious, like bicycling, would fill the void left by backyard trampoline play, these organizations have instead called for safety improvements tc disturbingly large number of trampoline injuries.

[0003] One approach to reducing trampoline injuries has been to form a wall around the perimeter of a trampoline bed so that when a jumper lands too near the edge, the wall prevents the jumper from falling off. Examples are shown in U.S. Pat. Nos. 5,399,132 and 6,053,845. However, these devices do not directly address injuries that result when users impact the rebounding surface incorrectly or while in an awkward position. A second approach, the use of a harness (worn by the jumper) suspended by elastic cords above the rebounding surface, is an effective way to reduce on-bed, or rebound surface impact injuries. However, such harnesses are designed for safely teaching users advanced acrobatics on high-performance competition trampolines by trained professionals, making them largely inappropriate for low-performance. Backyard trampolines are used almost entirely for basic jumping activities and not for advanced acrobatics.

{0004] All things being equal, a bed with less tension is more forgiving when a jumper first contacts its surface, it absorbs the impact more slowly and will thus redμce the severity and quantity of on-bed injuries. Nevertheless, injuries suffered during an impact with the rebounding surface are still occurring in large numbers on backyard trampoline beds even though these beds are designed to be less responsive and to have less initial surface tension than gymnastic grade, competition trampoline beds. Reducing bed-impact injuries, especially those that occur on backyard trampolines, was the purpose of the present invention, though the art can be used with all trampolines.

[0005] Low performance backyard trampolines are used very differently than high performance trampolines used by skilled competitors for training and competition. For instance, many on-bed backyard trampoline injuries occur when multiple jumpers are using the trampoline at the same time as reported in the NEISS data compiled by the CPSC. Because children enjoy playing together most families allow more than one child to jump at the same time even though this practice is strongly discouraged by trampoline manufacturers, the CPSC, and others experts. Competition trampolines are i exclusively in disciplined environments for the structured teaching of specific skills. Ih contrast, backyard trampolines are largely used for fun, unstructured, imaginative play activities that are relished by kids and recommended by child development experts who understand that daily physical activity significantly enhances learning ability and that kids need activities to counterbalance today's over-structured and sedentary lifestyles. Unfortunately, these unstructured trampoline activities generate numerous on-bed injuries when jumpers land on the rebounding surface in an awkward body position or when a jumper lands on a trampoline bed that has been preloaded with the energy from other jumper impacts.

[0006] There thus remains a need to significantly reduce the quantity and severity of on-bed injuries that result from such playful activities. Prior trampolines used a rebounding matt that is attached to a frame by a plurality of springs that have a fixed tension. The fixed tension is not suitable for all users as they very in body weight, age and strength.

[0007] It is therefore a first object of the present invention to provide an improved trampoline with adjustable springs.

- A -

Summary of Invention

[0008] In the present invention, the first object is achieved by proving a trampoline wherein the springs attach to the frame via an intermediate member whose length can be varied to modify the spring tension_*

[0009] The above and other objects, effects, features, and advantages of the present invention will become more apparent from the following description of the embodiments thereof taken in conjunction with the accompanying drawings.

Brief Description of Drawings

[0010] FIG. 1 is a plan view showing the trampoline rebounding matt and attachment to the trampoline frame.

[001 1 ] FIG. 2 is a perspective view of a trampoline rebounding matt, frame and springs showing where the spring tension is adjusted along the edge of the frame.

[0012] FIG. 3 is a cross sectional elevation showing the rotating pin and related structure as disposed withiii the bore trampoline frame.

[0013] FIG.4 is a cross sectional elevation showing the detailed construction of a first embodiment of the pin in FIG. 3.

[0014] FIG. 5 is a cross sectional elevation showing the detailed construction of a second embodiment of the pin in FIG. 3.

[001 5] FIG. 6 is an elevation of the pin of FIG. 5 from a viewpoint outside the trampoline frame, corresponding to section A-A in FIG. 5.

[0016] FIG. 7 is an external plan view of an alternative embodiment of the pin. [001 7] FIG. 8 is a cross-sectional elevation of the pin of FIG. 7.

[0018] It should be understood that FIG. 1-8 are not intended to be drawn to the same relative or absolute scale, but rather each figure is drawn at a scale to properly display and describe the interrelationship between the elements thereof. It being understood that one of ordinary skill in the art, can readily make adjustments thereto depending on the same and scale of the desired trampoline.

Detailed Description

[0019] Referring to FIGS. 1 through 8, wherein like reference numerals refer to like components in the various views, there is illustrated therein a new and improved trampoline with adjustable springs, generally denominated 100 herein.

[0020] Every potential player on a trampoline has a different strength-to-weight ratio. Thus, the ability to adjust or tune the system rebounding response for each player benefits their health and safety. In the instant invention the rebounding response it adjusted by varying the spring tension as shown and described below.

[0021] The basic operation and configuration of attaching a trampoline mat to a trampoline frame are taught in United States Patents and Published Application 6,261,207 (for a Trampoline or the like with enclosure ); 6,053,845 (for a Trampoline or the like with enclosure); 20040121883 ( for a Trampoline system); 2003/0104905 Al for a Trampoline system with plural beds ; 2003/0036460 Al (for a Trampoline system with adjustable spring elements) and 2002/0137598 Al (for a Trampoline or the like with enclosure), all of which are incorporated herein by reference.

[0022] In a preferred embodiment of the invention the tension in the adjacent or nearby spring alternate as taught in US Patent Application 2003/0036460 Al (for a Trampoline system with adjustable spring elements) such that the springs engage in "stages," instead of all a once, making for a softer initial impact. The instant invention provides for the tension of each spring to be individually adjusted providing a functionality that allows users to customize the bounce by tightening or loosening the spring connections at the external side of the spring frame. This inventive system gives the user control over the feel and performance during rebounding on the trampoline.

[0023] Accordingly, FIG. 1 illustrates in a perspective view a portion of a trampoline system that comprises a circular frame 12 held above the ground by a plurality of laterally downward extending legs 60. The rebounding matt or bed 14 is held in tension and suspected within frame 12 by coupling to the proximal ends of a plurality of spring, which are in turn coupled to the inside of the circular frame 12 at their distal ends. Coupling means a direct or indirect mechanical connection of two members.

[0024] As shown in more detail in the plan view of FIG. 2, springs 10 and 10' attach to the rebounding matt 14 at a plurality of locations around the perimeter via an intermediate plate 40. Intermediate plate 40 has central hole 41 and aperture 45 and 46 on opposite sides of the central hole 41 that receive fabric loops 51 and 52 sewn, stitched or otherwise adhered to the rebounding matt 14 at 54 and 53. The hooks like ends of one or more springs are inserted into central hole 41 to couple the springs 10 to the rebounding bed 14.

[0025] Referring to FIG. 3 it can be seen that the distal ends of the springs 10 and 10' are coupled to the circular frame 12 via pins 20 and 20' respectively. Each of the pins 20 and 20' have at least one hole or bore 21 for receiving the hook like distal end of the spring 10. The pins 20 extend through a bore 25 in the circular frame 12. Each pin has a head 28 that extends beyond the diameter of bore 25 coupling the pin 20 to the frame 12, fixing the lateral position of pin 20 with respect to frame 12.

[0026] In the preferred embodiment shown in FIG. 3, each pin 20 has a plurality 24 of holes 21, 22 and 23 for receiving the hook like distal end of spring 10. By attaching the distal end of each spring 10 to one of the plurality of holes 24, the spring tension is tunable between two, and preferably three or more discrete levels. As shown in FIG. 1 the trampoline frame 12 is supported above the ground by a plurality of legs 60.

[0027] It is generally desirable to locate and space holes 24 taking into account the stiffness of the springs 10 to be used, such that the middle setting, hole 22, is the optimal setting for users of average height and weight. Thus, a firmer bounce will be obtained by connecting all springs to the holes 23 most proximal to the trampoline frame 12. Conversely, a softer bounce will be obtained by connecting all springs to the holes 21 most distal from the trampoline frame 12

[0028] Adjusting the position of the end of springs in a hole selected from plurality 24 requires the user to pull back a protective pad (not shown) to expose the top ring 12 of the trampoline frame and the periphery of rebounding matt 14. The user then replaces the protective pad after selecting a different hole from plurality 24. after tightening or loosening spring connectors before use.

[0029] However, in the more preferred embodiments of FIG. 4-6 the spring tension can be adjusted while the pad is left in place. In such embodiments, the tension in each spring 10 is optionally varied continuously by adjusting the effective length of pin 20 while it is seated in bore 25. FIG. 4-6 illustrate further details of such pin and related mechanisms that permit the continuous adjustment of rebounding characteristics of mat 14. The adjustment range of each pin is preferably at least separation between holes in plurality 24.

[0030] In FIG. 4, the pin mechanism 20 is again disposed within a bore 25 through frame 12. However, pin 20 has in effect two portions 26 and 27 that can be translated relative to each other to shorten or length the pin, that is the distance between head 28 at the distal end of portion 26 and hole 21, disposed toward the proximal end of portion 27. Portion 26 includes head 28, whereas portion 27 includes the plurality of holes 24. Portion 27 has an internal bore 27a with internal threads 27b. The shaft of portion 26 opposite head 28 has exterior threads 26b that rotationally engage with threads 27b of portion 27. Head 28 includes a tool receiver opening 29 (for example a slot for a screw driver or hexagonal hole for an alien wrench) such that the corresponding tool can be used to rotate portion 26 while portion 27 is prevented from rotation by the resistance of spring 10.

[0031 ] FIG. 5 illustrates an alternative embodiment of the invention, shown in cross- sectional elevation, in which a spin lock mechanism 30 prevents the rotation of pin 20 by coupling the head 28 thereof to the frame 12. The spin lock mechanism 30 is a means for preventing the gradually loosening or movement of the threaded portion of the pin 20 from vibration. The spin lock mechanism 30 comprises relatively flat plate 38 having an inverted "L" shape connected by the narrower edge to the end of circular shaft 35. Note that a portion 38a of flat plate 38 is connected to the upper portion of circular shaft 35. The cooperative engagement of the flat plate 38 within slot 29 of head 28 is also illustrated in FIG. 6, which is an orthogonal elevational taken at section line A-A in FIG. 5. A spring 33 is attached to the other end of the circular shaft 35, both of which are in turn disposed with a second mating bore 34 formed within frame 12. The opposite end of spring 30, which is proximal to the interior of the trampoline, is fixed outside of bore 34 by end washer 36. Thus, spring 33 urges flat plate 38 inward toward frame 12 as it engages the slot 29 in head 28. It is also desirable that the upper portion 38a of flat plate 38 engage the vertical slot 12a in frame 12. Having flat plate 38 engage both slot 29 and slot 12a securely fixes the relative position of head 28 with respect to frame 12, thus preventing the unwanted rotation of pin 20 (and in particular portion 26 with respect to portion 27) However, when the user wishes to adjust the tension of spring 10, flat head 38 is readily disengaged from slots 29 and 12a by pulling it forward and rotating it 90 degrees. This alternative position for flat plate 38 (shown in dashed lines in FIG. 6 and labeled 38') clears the front of pin head 38 for receiving a screwdriver tip in slot 29 for rotating portion 26.

[0032] It will be apparent to one of ordinary skill in the art that alternative cooperative structures in frame 12 and pin 20 may be deployed to enable the lateral translation of holes in plurality 24 to vary the tension in spring 10 continuously. For example, pin 20 need not be formed of two portions, but may be externally threaded to engage female threads in bore 25. As it is desirable that the portion of pin 20 with the plurality of holes 24 not rotate about the axis of bore 25 when the head 28 is rotated to translate pin 20 with bore 25. One embodiment of such a pin 20 is illustrated FIG. 7 and 8. Accordingly, pin 20 has a freely rotating or bearing coupling 70 disposed between the portion 77 that includes the proximal end with holes 24 and the portion 76 that includes the distal end having head 28 and slot 29. Portion 76 has external thread 72 for engage a threaded coupling, insert or bore and the like that may be forming in or associated with frame 12. It will also be apparent that alternative methods of locking the head 28 of pin 20 are possible.

[0033] Further, referring back to FIG. 2, it should be appreciated that it is not essential to couple a pair of spring 10 and 10' to a common connection on the perimeter of mat 14 using intermediate plate 40. In alternative embodiments, each of the adjustable springs 10 may be connected or coupled to a discrete position on the perimeter of the mat 14 with a common connection of an adjacent spring. However, it should be appreciated that the embodiment shown and described with respect to FIG, 2 is preferred. While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be within the spirit and scope of the invention as defined by the appended claims.

Claims

[cl] A trampoline system comprising: a) a rebounding bed, b) a frame surrounding said rebounding bed that is suspended aboye the ground, c) a plurality of springs spaced about and coupled to the interior perimeter of said frame at the proximal end and coupled to the periphery of the rebounding bed at the distal end, d) wherein the proximal end of one or more of said springs is coupled to said frame via an intermediate bracket, the radial displacement of said bracket being variable to adjust the tension of said spring.

[c2] A trampoline system according to claim 1 wherein at least one pairs of adjacent springs in said plurality of spaced apart springs are couple to said rebounding bed at a common junction.

[c3] A trampoline system according to claim I wherein said bracket comprises a pin seated in a bore formed in said frame.

[c4] A trampoline system according to claim 3 wherein said bracket is laterally displaced by rotation of said pin.

[c5] A trampoline system according to claim 4 wherein said pin includes a first and a second concentric segment in mutual threaded engagement whereby rotation of one concentric segment with respect to the other concentric segment increases the effective length of said pin to laterally displace said bracket.

[c6] A trampoline system according to claim 3 wherein said pin is in threaded engagement within a threaded bore through said frame.

[c7] A trampoline system according to claim 6 wherein said pin has a freely rotary segment intermediate the connection with the bracket

[c8] A trampoline system according to claim 1 wherein one or more of said brackets has a plurality of holes at the distal end thereof for receiving a hook at the proximal end of said spring.

[c9] A trampoline system according to claim 3 wherein one or more of said brackets has a plurality of holes at the distal end thereof for receiving a hook at the proximal end of said spring.

[clO] A trampoline system according to claim 5 wherein one or more of said brackets has a plurality of holes at the distal end thereof for receiving a hook at the proximal end of said spring.

[cl 1 ] A trampoline system according to claim 1 and further comprising an intermediate plate for coupling said bracket to said rebounding bed.

[cl2] A trampoline system according to claim 11 wherein said intermediate plate is connected to the distal end of two or more springs.

[cl3] A trampoline system according to claim 11 wherein said intermediate plate is connected to the distal end of two or more springs at a central hole therein.

[cl4J A trampoline system according to claim 11 wherein said intermediate plate comprises one or more aperture that receive febric loops connected to said rebounding bed.

[cl 5] A trampoline system according to claim 4 wherein said pin can be locked to prevent rotation thereof

[cl6] A trampoline system according to claim 15 wherein said pin is locked by a plate that engages the head of the pin extending outward from said frame and a corresponding slot in said frame.

[cl7] A trampoline system according to claim 16 wherein said locking plate is attached to the frame is urged to engage in the head of said pin and the slot in said frame by a spring coupled to said frame.

[cl8] A pin assembly comprising a) a first elongated member having one or more holes associated with the distal end thereof and an internally thread bore on the proximal end, b) a second elongated member having a threaded distal end for engaging the internally threaded bore of said first elongated member, and a laterally extending head at the proximal end, wherein said head also comprises a cavity for receiving a tool head such that the second elongated member can be rotated with respect to the first elongated member.

[c 19] A trampoline system comprising: a) a rebounding bed, b) a frame surrounding said rebounding bed that is suspended above the ground, c) an elongated intermediate bracket coupled to said frame at the proximal end and extending inwards towards said rebounding mat at the distal end, and further comprising a plurality of holes spaced apart from said distal end, d) a plurality of springs spaced about and coupled to the periphery of the rebounding bed at the distal end, and attached to one of the holes in said plurality at the proximal end whereby the radial displacement of said spring by attachment to a different hole in said plurality varies the tension in said spring.

[c20] A trampoline system according to claim 19 wherein the radial displacement of said elongated bracket at the coupling to said frame is variable to adjust the tension of one or more of said springs without removing the connected spring from the hole in said bracket.