ATHLETICS HURDLE

Abstract

An athletics hurdle includes an upper cross bar assembly and a lower cross bar assembly. A post assembly interconnects the upper and lower cross bar assemblies. The post assembly includes a lower arm assembly that is mounted on the lower cross bar, and an upper arm assembly mounted on an upper end of the upper arm assembly. Two legs extend from ends of the lower cross bar assembly so that the hurdle is supported on the legs. The post assembly is mounted on the lower cross bar to be pivotal between an operative position and an inoperative position. Pivotal displacement of the post assembly from the operative position to an intermediate position is against a bias of a biasing mechanism and pivotal displacement of the post assembly from the intermediate position to the inoperative position is with a bias of the biasing mechanism.

Claims

1. An athletics hurdle which comprises: an upper cross bar assembly; a lower cross bar assembly; a post assembly that interconnects the upper and lower cross bar assemblies, the post assembly comprising a lower arm assembly that is mounted, at a lower end, on the lower cross bar, and an upper arm assembly, the upper cross bar assembly being mounted on an upper end of the upper arm assembly, the upper and lower arm assemblies being displaceable relative to each other to change a distance between the upper and lower cross bar assemblies; two legs that extend orthogonally from respective ends of the lower cross bar assembly so that the hurdle is supported on the legs, the post assembly being mounted on the lower cross bar to be pivotal between an operative position in which the post assembly is generally orthogonal to the legs, and an inoperative position in which the post assembly is generally aligned with the legs; and a biasing mechanism interposed between the post assembly and the lower cross bar assembly, the biasing mechanism being configured so that pivotal displacement of the post assembly from the operative position to an intermediate position between the operative and inoperative positions is against a bias of the biasing mechanism and pivotal displacement of the post assembly from the intermediate position to the inoperative position is with a bias of the biasing mechanism.

2. The athletics hurdle as claimed in claim 2, wherein the post assembly is pivotal with respect to the lower cross bar assembly and the biasing mechanism includes a compression spring assembly that is pivotally mounted on the lower cross bar assembly at an operatively lower end and is engaged with the lower arm assembly at an opposed upper end, an axis of rotation of the compression spring assembly being radially offset from an axis of rotation of the post assembly so that pivoting of the post assembly and the compression spring assembly towards the intermediate position compresses the spring assembly against a bias of the spring assembly, and pivoting of the post assembly and the spring assembly from the intermediate position to the inoperative position expands the spring assembly with a bias of the spring assembly.

3. The athletics hurdle as claimed in claim 2, which includes an adjustment mechanism that is interposed between the biasing mechanism and the post assembly, the adjustment mechanism being configured so that relative displacement of the upper and lower arm assemblies to increase a distance between the upper and lower cross bar assemblies compresses the spring assembly against the bias of the spring assembly to increase resistance of the post assembly to pivoting from the operative position to the intermediate position, and relative displacement of the upper and lower arm assemblies to reduce a distance between the upper and lower cross bar assemblies results in expansion of the spring assembly with the bias of the biasing mechanism to reduce resistance of the post assembly to pivoting from the operative position to the intermediate position.

4. The athletics hurdle as claimed in claim 3, wherein the lower arm assembly includes a tubular lower arm, and the upper arm assembly includes an upper arm that is received in the lower arm, the upper and lower arms being telescopically adjustable relative to each other.

5. The athletics hurdle as claimed in claim 4, wherein the adjustment mechanism includes a stop member that is fixed to the lower arm, and a slider that is slidable relative to the stop member, the stop member and the slider being configured so that the slider can slide reciprocally relative to the stop member on a path that is angled operatively rearwardly and upwardly with respect to the lower cross bar assembly.

6. The athletics hurdle as claimed in claim 5, wherein the stop member and the slider have complementary nesting formations that are shaped so that the relative displacement of the slider and the stop member is constrained to the path.

7. The athletics hurdle as claimed in claim 6, wherein the complementary nesting formations are in the form of a rail of the slider and a slot of the stop member, the rail being interlocked with the slot to inhibit disconnection from the stop member.

8. The athletics hurdle as claimed in claim 6, wherein the stop member includes a travel limit formation at an operatively upper end of the path to limit displacement of the slider.

9. The athletics hurdle as claimed in claim 8, wherein a compression spring is interposed between the slider and the travel limit formation to dampen displacement of the slider.

10. The athletics hurdle as claimed in claim 5, wherein the upper arm assembly includes a displacement mechanism that is operatively engaged with the slider to displace the slider relative to the stop member, the displacement mechanism being configured so that the slider slides with respect to the stop member towards the lower cross bar assembly as the upper arm assembly is displaced relative to the lower arm assembly to increase a distance between the upper and lower cross bar assemblies, to compress the spring assembly against the bias, and away from the lower cross bar assembly as the upper arm assembly is displaced relative to the lower arm assembly to decrease a distance between the upper and lower cross bar assemblies, to allow the spring assembly to expand with the bias.

11. The athletics hurdle as claimed in claim 10, wherein the displacement mechanism includes a guide formation, the slider being slidably arranged with respect to the guide formation, the guide formation being oriented so that the slider slides towards the lower cross bar assembly as the upper arm assembly is displaced relative to the lower arm assembly to increase a distance between the upper and lower cross bar assemblies, and away from the lower cross bar assembly as the upper arm assembly is displaced relative to the lower arm assembly to decrease a distance between the upper and lower cross bar assemblies.

12. The athletics hurdle as claimed in claim 11, wherein the upper arm is hollow, and the displacement mechanism includes two opposed guide members that are arranged facing each other in the upper arm, the guide formation being in the form of opposed guide channels in respective guide members, the guide channels extending along a line that is angularly offset, in a direction of rotation of the post assembly, with respect to a longitudinal axis of the spring assembly, and the slider including two projections slidingly received in respective guide channels.

13. The athletics hurdle as claimed in claim 12, wherein the upper arm is tubular and has a rectangular or square cross section with two opposed side walls, a front wall, and a rear wall, and the guide members are in the form of generally flat members that are fastened to respective side walls of the upper arm with the stop member interposed between the guide members.

14. The athletics hurdle as claimed in claim 13, wherein the lower arm has a rectangular or square cross section with two opposed side walls, a front wall, and a rear wall, with the front and rear walls of the upper arm defining opposed elongate slots to accommodate front and rear sides of the stop member that is fastened to the front and rear walls of the lower arm, the slots being dimensioned to accommodate the stop member as the upper and lower arms are displaced relative to each other to adjust the distance between the upper and lower cross bar assemblies.

15. The athletics hurdle as claimed in claim 5, wherein the compression spring assembly includes a strut assembly having a top strut and a bottom strut, the struts being telescopically arranged relative to each other, and upper and lower spring seats mounted on the top and bottom struts, respectively, a coil spring being seated between the spring seats.

16. The athletics hurdle as claimed in claim 15, wherein the slider is pivotally mounted on an operatively upper end of the top strut.

17. The athletics hurdle as claimed in claim 16, wherein an operatively lower end of the bottom strut is pivotally mounted on the lower cross bar assembly.

18. The athletics hurdle as claimed in claim 17, wherein the lower cross bar assembly includes a cylindrical cross bar and a collar assembly that is rotatably mounted on the cross bar, the lower end of the lower arm of the lower arm assembly being fixed to the collar assembly so that the axis of rotation of the post assembly is collinear with a central, longitudinal axis of the cross bar.

19. The athletics hurdle as claimed in claim 18, wherein the lower end of the bottom strut is pivotally mounted on the cross bar so that the axis of rotation of the bottom strut is offset from the axis of rotation of the post assembly on an arc between the operative and inoperative positions of the post assembly.

20. The athletics hurdle as claimed in claim 4, wherein the upper arm defines a series of openings extending along the length of the upper arm while the lower arm defines a single opening, the openings being dimensioned and positioned so that the upper arm can be displaced relative to the lower arm so that any one of the openings in the upper arm can be brought into register with the opening in the lower arm to allow the distance between the upper and lower cross bar assemblies to be adjusted by pinning the upper and lower arms together.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG. 1 shows a rear three-dimensional view of an embodiment of an athletics hurdle.

[0035] FIG. 2 shows a front three-dimensional view of the athletics hurdle.

[0036] FIG. 3 shows a schematic side view of the athletics hurdle with an upper cross bar assembly at different heights.

[0037] FIG. 4 shows an exploded front view of the athletics hurdle.

[0038] FIG. 5 shows an exploded front view of various components of the athletics hurdle.

[0039] FIG. 6 shows a side view of a biasing mechanism of the athletics hurdle with the upper cross bar assembly in a raised position.

[0040] FIG. 7A shows a front three-dimensional view of the biasing mechanism of FIG. 6.

[0041] FIG. 7B shows a detailed side view of a slider and a stop mechanism of the biasing mechanism of FIG. 6.

[0042] FIG. 8 shows a side view of the biasing mechanism with the upper cross bar assembly in a partially raised position.

[0043] FIG. 9 shows a three-dimensional view of the biasing mechanism of FIG. 8.

[0044] FIG. 10 shows a schematic side view of the athletics hurdle in operative and inoperative conditions.

[0045] FIG. 11 shows a more detailed schematic side view of the athletics hurdle in operative and inoperative conditions.

DETAILED DESCRIPTION

[0046] In the drawings, reference numeral 10 generally indicates an embodiment of an athletics hurdle, in accordance with the invention.

[0047] The athletics hurdle 10 includes an upper cross bar assembly 12 and a lower cross bar assembly 14. A post assembly 16 interconnects the upper and lower cross bar assemblies 12, 14. The post assembly 16 has a lower arm assembly 18 (FIG. 4) that is pivotally mounted, at a lower end, on the lower cross bar assembly 14. The post assembly 16 has an upper arm assembly 20. The upper cross bar assembly 12 is mounted on the upper arm assembly 20. The upper and lower arm assemblies 20, 18 are adjustable relative to each other to adjust a distance between the upper and lower cross bar assemblies 12, 14, and thus the overall height of the hurdle 10. An example of the different heights is indicated in FIG. 3.

[0048] The hurdle 10 includes two legs 22, 24 that extend orthogonally from respective ends of the lower cross bar assembly 14. The legs 22, 24 and the lower cross bar assembly 14 support the hurdle 10. The legs 22, 24 can have a length of about 700 mm. Static stability weights can be arranged on the legs 22, 24 for stabilising the hurdle 10.

[0049] The post assembly 16 could be fixed to the lower cross bar assembly 14, which could be rotational relative to the legs 22, 24.

[0050] The post assembly 16 can pivot about an axis of rotation 17 (FIG. 1) between an operative position in which the post assembly 16 is orthogonal to the legs 22, 24, and an inoperative position in which the post assembly 16 is aligned with the legs 22, 24 (position B in FIGS. 10 and 11).

[0051] The hurdle 10 includes a biasing mechanism 26 (FIG. 5) that is interposed between the post assembly 16 and the lower cross bar assembly 14. The biasing mechanism 26 is configured so that pivotal displacement of the post assembly 16 from the operative position to an intermediate position between the operative and inoperative positions is against a bias of the biasing mechanism 26, and pivotal displacement of the post assembly 16 from the intermediate position to the inoperative position is with a bias of the biasing mechanism 26.

[0052] The athletics hurdle 10 includes an adjustment mechanism 25 (FIG. 5) that is interposed between the biasing mechanism 26 and the post assembly 16. The adjustment mechanism 25 is configured so that relative displacement of the upper and lower arm assemblies 20, 18 to increase a distance between the upper and lower cross bar assemblies 12, 14 increases a bias of the biasing mechanism 26, and relative displacement of the upper and lower arm assemblies 20, 18 to decrease a distance between the upper and lower cross bar assemblies 12, 14 decreases a bias of the biasing mechanism 26. Thus, a bias of the biasing mechanism 26 can be increased to compensate for an increase in torque applied at the lower cross bar assembly 14, when the upper cross bar assembly 12 is struck, as a result of lifting the upper cross bar assembly 12, and decreased to compensate for a decrease in torque applied at the lower cross bar assembly 14 as a result of lowering the upper cross bar assembly 12.

[0053] The biasing mechanism 16 includes a compression spring assembly 28 (FIG. 5). An operatively lower end of the spring assembly 28 is pivotally mounted on the lower cross bar assembly 14. An operatively upper end of the spring assembly 28 is engaged with the lower arm assembly 18, via the adjustment mechanism 25. The axis of rotation of the spring assembly 28 is radially and rearwardly offset with respect to the axis of rotation 17 of the post assembly 16 such that pivoting of the post assembly 16 and the spring assembly 28 from the operative position to the intermediate position compresses the spring assembly 28 against a bias, and pivoting of the post assembly 16 and the spring assembly 28 from the intermediate position to the inoperative position expands the spring assembly 28 with a bias of the spring assembly 28. Thus, pivotal movement of the post assembly 16 to the intermediate position is against the bias of the spring assembly 28, and pivotal movement of the post assembly 16 from the intermediate position to the inoperative position is with the bias of the spring assembly 28.

[0054] The adjustment mechanism 25 is configured so that relative displacement of the upper and lower arm assemblies 20, 18 to increase the distance between the upper and lower cross bar assemblies 12, 14 results in compression of the spring assembly 28 to increase resistance of the post assembly 16 to pivoting from the operative position to the intermediate position, and relative displacement of the upper and lower cross bar assemblies 12, 14 to decrease the distance between the upper and lower cross bar assemblies 12, 14 results in decompression or expansion of the spring assembly 28 to decrease the resistance of the post assembly 16 to pivoting from the operative position to the intermediate position.

[0055] The lower arm assembly 18 includes a tubular lower arm 32 (FIG. 4). The upper arm assembly 20 includes an upper arm 34 that is received in the lower arm 32. The upper and lower arms 34, 32 are telescopically adjustable relative to each other to change the height of the hurdle 10.

[0056] The adjustment mechanism 25 includes a stop member 36 that is fixed to the lower arm 32, and a slider 30 that is slidable relative to the stop member 36. The stop member 36 and the slider 30 are configured so that the slider 30 can slide reciprocally relative to the stop member 36 on a path that is angled operatively rearwardly and upwardly with respect to the lower cross bar assembly 14, when the post assembly 16 is in an operative position.

[0057] The stop member 36 and the slider 30 have complementary nesting formations shaped so that relative displacement of the slider 30 and the stop member 36 is constrained to the path. The nesting formations are in the form of a rail 38 of the slider 30 and a slot 40 of the stop member 36. The rail 38 is interlocked with the slot 40 to inhibit disconnection from the stop member 36. To that end, the slot 40 defines opposed lateral recesses 41 (FIG. 9). The rail 38 defines opposed lateral projections 39 that are slidable in the respective recesses 41.

[0058] The stop member 36 includes a travel limit formation 42 at an upper end of the path to limit upward displacement of the slider 30.

[0059] The upper arm assembly 20 includes a displacement mechanism that is operatively engaged with the slider 30 to displace the slider 30 relative to the stop member 36. The displacement mechanism is configured so that the slider 30 slides with respect to the stop member 36 towards the lower cross bar assembly 14 as the upper arm assembly 20 is displaced relative to the lower arm assembly 18 to increase a distance between the upper and lower cross bar assemblies 12, 14, to compress and so increase tension in the spring assembly 28. The slider 30 slides with respect to the stop member 36 away from the lower cross bar assembly 14 as the upper arm assembly 20 is displaced relative to the lower arm assembly 18 to decrease a distance between the upper and lower cross bar assemblies 12, 14, to allow the spring assembly 28 to expand to decrease tension in the spring assembly 28.

[0060] The athletics hurdle 10 includes a guide formation. The slider 30 is slidably arranged with respect to the guide formation. The guide formation is oriented so that the slider 30 slides towards the lower cross bar assembly 14 as the upper arm assembly 20 is displaced relative to the lower arm assembly 18 to increase a distance between the upper and lower cross bar assemblies 12, 14, and away from the lower cross bar assembly 14 as the upper arm assembly 20 is displaced relative to the lower arm assembly 18 to decrease a distance between the upper and lower cross bar assemblies 12, 14.

[0061] The upper arm 34 is hollow. The displacement mechanism includes two opposed guide members 46. The guide members 46 are arranged facing each other in the upper arm 34. The guide formation is in the form of opposed guide channels 48 in respective guide members 46. Each guide channel 48 extends along a line that is angularly offset, in a direction of rotation of the post assembly 16, with respect to a longitudinal axis of the spring assembly 28. The slider 30 includes two projections 50 that are slidingly received in respective guide channels 48.

[0062] A compression spring 44 is interposed between the slider 30 and the travel limit formation 42. A spring retainer 51 (FIG. 7a) projects from the travel limit formation 42 towards the slider 30. The retainer 51 is received within the spring 44. The spring 44 interconnects the slider 30 and the formation 42. When the distance between the upper and lower cross bar assemblies 12, 14 is increased to a predetermined extent, the projections 50 can at least partially exit the channels 48 and can become disengaged from the guide members 46. The spring 44 serves to retain the slider 30 in position against the stop member 36 (FIG. 6, 7), in that condition.

[0063] The upper arm 34 is tubular and has a rectangular or square cross section. The upper arm 34 has two opposed side walls 52, a front wall 54, and a rear wall 56 (FIG. 10). The guide members 46 are generally flat members and are fastened to respective side walls 52 of the upper arm 34. The stop member 36 is interposed between the guide members 46.

[0064] The lower arm 32 has a rectangular or square cross section. The lower arm 32 has two opposed side walls 58, a front wall 60, and a rear wall 62.

[0065] The front and rear walls 54, 56 define opposed elongate slots 64 (FIG. 4) to accommodate front and rear sides 66, 67 of the stop member 36 (FIG. 6). The stop member 36 is fastened to the front and rear walls 60, 62 of the lower arm 32 via the slots 64. The slots 64 are dimensioned to accommodate the stop member 36 as the upper and lower arms 34, 32 are displaced relative to each to adjust the distance between the upper and lower cross bar assemblies 12, 14. The stop member 36 defines openings 37 (FIG. 9) to facilitate fastening of the stop member 36 to the front and rear walls 60, 62.

[0066] The compression spring assembly 28 includes a strut assembly 68 (FIG. 7). The strut assembly 68 has a top strut 70 and a bottom strut 72. The struts 70, 72 are telescopically arranged relative to each other. Upper and lower spring seats 74, 76 are mounted on the top and bottom struts 70, 72, respectively. A coil spring 78 is seated on and between the spring seats 74, 76.

[0067] The slider 30 is mounted on an upper end 110 of the top strut 70. The slider 30 can be pivotally mounted on the upper end 110. The upper end 110 is rounded or otherwise shaped to engage a complementary formation on the slider 30 to accommodate relative pivotal movement of the slider 30 and the strut 70 as the post assembly 16 pivots with respect to the lower cross bar assembly 14. A lower end of the bottom strut 72 is pivotally mounted on the lower cross bar assembly 14.

[0068] The bottom strut 72 includes a threaded lower portion 106. A nut 108 is threaded onto the lower portion 106, with the lower spring seat 76 interposed between the nut 108 and the spring 78.

[0069] The lower cross bar assembly 14 includes a cylindrical, tubular cross bar 80 (FIG. 4). A collar assembly 82 is rotatably mounted on the cross bar 80. The lower end of the lower arm 32 is fixed to the collar assembly 82 so that the axis of rotation 17 of the post assembly 16 is collinear with a central, longitudinal axis of the cross bar 80.

[0070] The lower end of the bottom strut 72 is pivotally mounted on the cross bar 80 so that an axis of rotation 49 of the bottom strut 72 (FIG. 9) is radially and rearwardly offset with respect to the axis of rotation 17 of the post assembly 16.

[0071] The collar assembly 82 comprises collar members 84 that are assembled on the lower cross bar 80 (FIG. 5). The collar members 84 have complementary fastening or clipping formations 83 so that the collar members 84 can be clipped to each other about the lower cross bar 80. The collar members 84 are shaped so that the collar assembly defines a slot 86 (FIG. 4) to receive a lower end 85 of the lower arm 32. The lower end 85 is profiled to nest with the cross bar 80 in the slot 86 so that the lower arm 32 can pivot about the axis 17. The collar members 84 are interlocking components that can be secured to the lower cross bar 80 without being slid onto the lower cross bar 80.

[0072] The cross bar 80 is fastened to the legs 22, 24 with gussets 118 (FIG. 4). The gussets 118 can be screwed or welded between the cross bar 80 and the legs 22, 24.

[0073] A pivot bracket 88 is fastened to the cross bar 80 in the slot 86 (FIG. 5). To that end, the pivot bracket 88 defines a plurality of openings 89 (FIG. 9) so that fasteners can be used to fasten the pivot bracket 88 to the cross bar 80. The slot 86 is dimensioned to accommodate limited rotational movement of the bracket 88 relative to the collar assembly 82 that corresponds to the pivotal movement of the post assembly 16 between the operative and inoperative positions. The bottom strut 72 is pivotally mounted on the pivot bracket 88. A leg 112 of a T-bar 114 projects from the threaded lower portion 106. An arm 116 of the T-bar 114 is pivotally engaged with the pivot bracket 88 to facilitate pivoting of the bottom strut 72 with respect to the cross bar 80. The position of the pivot bracket 88 is such that the axis of rotation 49 is radially and rearwardly offset with respect to the axis of rotation 17.

[0074] The upper arm 32 defines a series of openings 90 extending along a length of the upper arm 34 (FIG. 4). The lower arm 32 defines a single opening 92. The openings 90, 92 are dimensioned and positioned so that the upper arm 34 can be displaced relative to the lower arm 32 so that any of the openings 90 can be brought into register with the opening 92 to allow the distance between the upper and lower cross bar assemblies 12, 14 to be adjusted by pinning the upper and lower arms together, via the openings 90, 92, at a desired position.

[0075] The dimensions of the upper cross bar assembly 12, and the upper and lower arms 34, 32, and the positions of the opening 90, 92, are such that the overall height of the of the hurdle 10, that is a jumping height of the hurdle 10, can have five different values to comply with World Athletics regulations. These are 762 mm, 838 mm, 914 mm, 991 mm, and 1067 mm, as shown in FIG. 3.

[0076] Operation of the athletics hurdle 10 is shown in FIGS. 10 and 11. The hurdle 10 is shown in the operative position (A) and in the inoperative position (B), with an arrow 120 indicating a direction of movement from the operative to the inoperative positions. A dotted circle 94 shows an arc of travel about the axis 49 that would be taken by the slider 30 as the post assembly 16 pivots from the operative position (A) to the inoperative position (B). The axis 49 is shown as point 101 in FIG. 11. However, the slider 30 is constrained to an arc of travel shown by a solid circle 96, which is the arc of travel of the stop member 36 as the post assembly 16 pivots from the operative position (A) to the inoperative position (B) about the axis 17. The axis 17 is shown as point 99 in FIG. 11. The relative positions of the points 99 and 101 show the direction of offset of the axes 17, 49. The circles 94, 96 are superimposed for illustrative purposes. As can be seen, the circles 94, 96 intersect at the operative and inoperative positions, respectively. Between those positions, the offset between the circles 94, 96 is greatest at an angle from the operative position in a clockwise direction. As can be seen, the angle is an included angle defined by dotted lines 102, 104, as described earlier. In this embodiment, is 45 degrees. That can vary depending on factors such as fabrication parameters. Thus, movement of the post assembly 16 through the angle from the position A compresses the spring 78 and is against the bias, while movement past the angle into the position B allows the spring 78 to expand and is with the bias. The dotted line 102 therefore illustrates the intermediate position of the post assembly 16.

[0077] This is due to the radially offset axis of rotation 49 of the spring assembly 28 relative to the axis of rotation 17 of the post assembly 16. This indicates that rotation of the post assembly 16 from the operative position to the intermediate position is against a bias of the spring assembly 28, while rotation of the post assembly 16 from the intermediate position to the inoperative position is with a bias of the spring assembly 28.

[0078] The hurdle 10 differs from conventional hurdles in the way that the upper cross bar assembly 12 is restrained from falling to the ground on impact because of the bias exerted on the post assembly 16 in an arcuate range of movement between the lines 102, 104, through a degrees.

[0079] World Athletics requires that hurdles provide a horizontal resistance at the upper cross bar of 3.6 kg to 4.0 kg at each of the five cross bar heights referenced above.

[0080] The resistance to toppling in conventional hurdles is provided by counterweights in each leg that can be moved back and forth depending on the height of the cross bar. It will be appreciated that torque at the lower cross bar increases proportionally to the strike force exerted at the upper cross bar as the height of the upper cross bar increases. The counterweights of conventional hurdles are moved back and forth to adjust the required strike force. This is done by manually moving pins attached to the counterweights, or automatically moving the counterweights via cables attached to telescopic arms supporting the upper cross bar.

[0081] As described above, a position of the upper arm 34 relative to the lower arm 32 is related to an extent of compression of the spring assembly 28. Raising the upper cross bar assembly 12 results in compression of the spring assembly 28, so increasing the torque required to pivot the post assembly 16 from the operative position to the intermediate position. Conversely, lowering the upper cross bar assembly 12 results in expansion of the spring assembly 28, so reducing the torque required to pivot the post assembly 16 from the operative position to the intermediate position.

[0082] In FIGS. 6 and 7, the upper arm 34 has been raised to increase the height of the upper cross bar assembly 12. This has caused the slider 30 to slide along the path towards the lower cross bar assembly 14, so compressing the spring assembly 28. In FIGS. 8 and 9, the upper arm 34 has been lowered to decrease the height of the upper cross bar assembly 12, so expanding the spring assembly 28. Thus, the characteristics and mounting position of the spring assembly 28 can readily be calculated and selected to achieve a consistent strike force at any height of the upper cross bar assembly 12.

[0083] In one embodiment, the spring assembly 28 and the slide 30 are configured so that a maximum resistance of between 35 N and 40 N is experienced at the upper cross bar assembly 12 during rotation from 0 degrees to 15 degrees from the operative position. On initial contact, the resistance can be about 20 N and can increase to the maximum at 15 degrees. As the post assembly 16 rotates past 15 degrees, the spring assembly 28 can hold a position of the post assembly 16 until about 40 degrees. Then the weight of the post assembly 16 and the upper cross bar assembly 12, and the action of the spring assembly 28 work together to pivot the post assembly 16 into the inoperative position.

[0084] In one embodiment, the spring used is 54 mm long, has a diameter of 26 mm, and has 6 coils. The coils are of 316 stainless steel and have a diameter of 6.2 mm. The spring coefficient is approximately 400 N/mm.

[0085] The upper cross bar assembly 12 includes an upper cross bar 98 that is mounted on the upper arm 34 with opposed support struts 100 (FIG. 4).

[0086] In use, the legs 22, 24 face away from the oncoming athlete. This provides a clean look for the athlete.

[0087] In the inoperative position, the legs 22, 24 are generally aligned with the post assembly 16. This can save significant storage and transport space when compared with a conventional hurdle. This is useful given that many hurdles are used during events. It is estimated that the hurdle 10 will require up to 45 percent less storage and transport space than conventional hurdles.

[0088] When the hurdle 10 is struck with the required force, the legs 22, 24 remain in position while the post assembly 16 and the upper cross bar assembly 12 pivot onto the ground between the legs 22, 24. It follows that the legs 22, 24 are inhibited from lifting off the ground and becoming hazardous to the athlete and other athletes.

[0089] It is expected that the added safety of the hurdle 10, when compared to conventional hurdles, will result in the athlete attacking the hurdle more aggressively, which would improve times. It is also expected that the reduction in injuries resulting from the use of the hurdle 10 would reduce recovery time, which is usually time away from training.

[0090] The hurdle 10 has been found to be approximately 1.2 kg lighter than an equivalent conventional hurdle.

[0091] The various components of the hurdle 10 can be of a material with appropriate structural integrity to accommodate the use of the hurdle 10. For example, the components can be of a metal such as steel, aluminium, and various alloys thereof, or can be of composite plastics materials, fibre glass, or carbon fibre.

[0092] Operation of the hurdle 10 is simpler than operation of conventional hurdles. For example, height adjustment automatically adjusts resistance to falling so that further operations such as adding weights to the legs when adjusting the height of multiple hurdles is not required. This can save a significant amount of time. Furthermore, the fact that the hurdle 10 is less likely to move significantly when knocked down, compared to a conventional hurdle, can save time and effort when setting the hurdles up for different events.

[0093] The appended claims are to be considered as incorporated into the above description.

[0094] Throughout this specification, reference to any advantages, promises, objects or the like should not be regarded as cumulative, composite, and/or collective and should be regarded as preferable or desirable rather than stated as a warranty.

[0095] Throughout this specification, unless otherwise indicated, comprise, comprises, and comprising, (and variants thereof) or related terms such as includes (and variants thereof), are used inclusively rather than exclusively, so that a stated integer or group of integers may include one or more other non-stated integers or groups of integers.

[0096] When any number or range is described herein, unless clearly stated otherwise, that number or range is approximate. Recitation of ranges of values herein are intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value and each separate subrange defined by such separate values is incorporated into the specification as if it were individually recited herein.

[0097] Words indicating direction or orientation, such as front, rear, back, etc, are used for convenience. The inventor(s) envisages that various embodiments can be used in a non-operative configuration, such as when presented for sale. Thus, such words are to be regarded as illustrative in nature, and not as restrictive.

[0098] Features which are described in the context of separate aspects and embodiments of the invention may be used together and/or be interchangeable. Similarly, features described in the context of a single embodiment may also be provided separately or in any suitable sub-combination.

[0099] It is to be understood that the terminology employed above is for the purpose of description and should not be regarded as limiting. The described embodiments are intended to be illustrative of the invention, without limiting the scope thereof. The invention is capable of being practised with various modifications and additions as will readily occur to those skilled in the art.