US20160310815A1

US20160310815A1 - Elastic tethered practice balls

Info

Publication number: US20160310815A1
Application number: US14/691,822
Authority: US
Inventors: Scott Peter Anderson
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-04-21
Filing date: 2015-04-21
Publication date: 2016-10-27

Abstract

Tethered practice ball apparatus including: an elastic tether; ball or a ball substitute for the game being practised operatively secured to the elastic tether; and a harness for securing the tether to a practising athlete, the harness including a body mount forming a termination for the tether and which may be selectively and securely positioned on a user's torso whereby the rebound force vector applied by a stretched tether will direct the returning practice ball toward a selected target on or adjacent the practising athlete.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
This invention relates to elastically tethered practice balls. The invention has particular application to elastically tethered practice ball apparatus incorporating practice balls elastically tethered to a user and which may be used by an individual to practice ball skills.
2. Description of Related Art
Elastically tethered practice balls have been provided for practising many types of games. These vary from games such as tennis, where the ball is struck by a bat or racquet, to games such as football, where the ball is handled and propelled by the user. While such available practice apparatus are mostly simple in concept and inexpensive and may be suitable for introducing new players to a particular ball skill, most such practice apparatus have not achieved widespread adoption, especially for committed athletes wanting to improve their game skills.
One of the major difficulties with such practice apparatus is the lack of replication of the ball travel as would occur in the game being practiced. Another disadvantage of such practice apparatus is the lack of variation of ball skills which may be practised with any one form of elastically tethered practice ball.

SUMMARY OF THE INVENTION

This invention aims to provide elastically tethered practice ball apparatus and parts therefore which will alleviate at least one of the abovementioned disadvantages. Other aims and aspects of this invention will become apparent from the following description.
With the foregoing in view, this invention in one aspect resides broadly in tethered practice ball apparatus including:
an elastic tether;
a ball or a ball substitute for the game being practised operatively secured to the elastic tether; and
a harness for securing the tether to a practising athlete, the harness including a body mount forming a termination for the tether and which may be selectively and securely positioned on a user's torso whereby the rebound force vector applied by a stretched tether will direct the returning practice ball toward a selected target on or adjacent the practising athlete.
In the preferred form of the invention and particularly when adapted for use with a football, swivel means is provided between the harness and the ball so that torsional loads which may be induced in the elastic tether during practice may be dissipated without causing the tethered ball to over rotate in reaction to the induced torsional loads.
The swivel means may be incorporated in the elastic tether or in its mounting to the football or to the body mount. Preferably the swivel means is incorporated in, on or adjacent the body mount as this arrangement enables the elastic tether only to extend from the swivel to the practice ball whereby the possibility of injury or damage being caused by propelling the ball or by the returning ball, swivel and tether is reduced.
The swivel means may include a through passage in the body mount through which the tether may extend and be terminated such that it is not restrained from rotating within the through passage. For this purpose the tether may be terminated within a bearing shell adapted for free rotational location within the through passage. This arrangement is preferred as it minimises projections from the body mount which may cause an athlete to move unnaturally during active practice through concern of injury by striking any such protrusion.
The harness suitably includes height adjusting means, such as a shoulder support, which may be adjusted to selectively position the body mount on a user. The height adjusting means may be an adjustable mounting on the harness such as a velour-crochet (hook and loop) mounting. The harness also includes adjustment means for adjusting the harness to suit each user and preferably in a manner which enables the body mount to be secured in a substantially fixed position close to the user's torso.
Preferably the harness includes an adjustable torso strap or straps which extends directly from the body mount so that in use, the torso strap or straps may be tightened to hold the body mount firmly against a user's torso whereby loads applied by the stretched elastic tether to the body mount may be taken directly by the torso strap or straps. The body mount may have provision for removably receiving one or both ends of the or each torso strap such as by having an accessible recess for a slide-in clip for each received strap end which form terminations for the torso strap ends or loops through which the strap ends may be returned to adjustment means which may be remote from the body mount. Each torso strap may be an assembly of strap portions extending from opposite sides of a back panel which may be a padded panel if desired.
The height adjusting means may include an adjustable shoulder strap for locating the body mount at a selected height on the torso of a user. A single adjustable shoulder strap may connect between the front portion of the harness and the back portion of the harness or the single shoulder strap may extend across both shoulders and about the user's neck from the front part of the harness so as to hold the body mount at a selected height on a user's torso. Preferably a pair of adjustable shoulder straps is provided extending from a back connection to the torso strap or straps to a front termination on or adjacent the body mount.
In a preferred embodiment the ends of a torso strap assembly has its ends terminated by respective opposite side parts of a slide-in clip assembly which forms the body mount. Preferably the clip assembly has a central receiving part for receiving the opposite side parts and being provided with a substantially centrally disposed swivel mount at which the tether is terminated. The swivel mount may be a through passage supporting a retained rotatable sleeve through which the tether may pass to an enlarged portion which may be constituted by a knot in the tether or other attachment to the tether. Preferably the central receiving part has side recesses therein to receive and secure spaced latching prongs of the respective side parts.
In one embodiment of the invention adapted for practising football the connection of the tether to the practice ball is a connection formed centrally in the laced bladder opening of a football which is a reinforced part of the football remote from its preferred foot contact zone. Preferably the connection is a releasable connection such that the football may be released and used in conventional play or practice.
In another embodiment of the invention the connection is an elastic strop which, when not in use retracts to lie closely against the football where it will not make a significant difference to normal use of the football and which may be pulled away from the football to enable the tether to be secured around the strop.
The tether may be secured about the strop by returning the tether back upon itself and by securing the standing and returned parts of the tether with removable ties or elastic rings or by tying off if desired. The tether could also be connected to an end portion of a non-spherical practice ball if desired or to any location of a spherical ball such as a soccer ball.
In another aspect this invention resides in a method of practising football by securing an elastically tethered football to a user in a manner whereby the tether is adjustably retained on the user for retention at selected positions of the upper torso of the user and adjusting the position of the tether mount such that the rebound force vector applied by a stretched tether will direct the returning practice ball toward a portion of the user's body selected for practising a particular catch such as a high or low catch or a running catch, for example as well as the kicking needed to provide such a catch to another player. In another form, a football provided with a laced bladder opening for access to the bladder has apertures at opposite sides of a bladder flange and a tether connection is provided by an elastic cord passed through the apertures and tied off so that the elastic cord bridges the bladder opening.
In a further aspect this invention resides broadly in a harness for securing an elastically tethered practice ball to a user, the harness including:
a body mount for securing a tether;
height adjusting means for selectively adjusting the height of the body mount on a user's torso; and
an adjustable torso strap assembly which connects directly to the body mount so that in use, the torso strap assembly may be tightened to hold the body mount firmly against a user's torso.
Preferably the body mount includes swivel means for rotatably securing a tether thereto which may include a through passage in the body mount rotatably supporting a hollow retainer in which an enlarged end portion of a tether may be substantially confined for retention therein.
In a further aspect this invention resides in a football having a laced bladder opening provided with tether connections at opposite sides of the bladder opening for a tether connection. The tether connections are suitably apertures through the opposed lacing portions of the football and suitably a short elastic cord is passed through these apertures and tied off so that the elastic cord bridges the bladder opening and is unobtrusive when not being used to connect the football to a tether for practising according to this invention.
The detachable connection of the tether to the harness may be accommodated by providing a passage through the swivelling part of the swivel through which a short length of the tether may be passed, the passage being larger than the cross section of the tether. In such form, a wedge may be provided to insert into the passage from the front or the rear to hold the tether at the desired position. Alternatively, a screw may be provided with a tapered threadform which can be rotated into the passage to wedge the tether in place. In a further alternative, a clamp may be clamped onto the tether to abut the swivel. With each of the alternative forms, the tether may be quickly released and pulled through the passage one way or the other. Any excess length at the player end of the tether may be tucked under a shoulder strap or waist band according to the preference of the player.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that this invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate preferred embodiments of the invention, wherein:—

FIG. 1 is a diagrammatic view illustrating use of one embodiment of elastically tethered practice football apparatus;

FIG. 2 is a diagrammatic front view illustrating a typical arrangement for utilising the elastically tethered practice ball apparatus;

FIG. 3 is a front view of one form of harness;

FIG. 4 illustrates the arrangement of the elastic tether;

FIG. 5 is an end view illustrating the connection at the laced bladder opening for releasably connecting the tether to the football;

FIG. 6 is a plan view illustrating connection details to the based bladder opening;

FIG. 7 illustrates another form of harness;

FIGS. 8 and 9 are further diagrammatic views illustrating another use of the practice football apparatus;

FIGS. 10 to 13 illustrate further connections to a football;

FIGS. 14 and 15 illustrate a first arrangement for securing the tether to the harness;

FIGS. 16 and 17 illustrate a second arrangement for securing the tether to the harness;

FIGS. 18 and 19 illustrate a third arrangement for securing the tether to the harness;

FIG. 20 illustrates a clip-on swivel for the harness;

FIG. 21 illustrates a mid-section swivel clip for the harness;

FIG. 22 illustrates a fixed strap arrangement for the harness;

FIG. 23 illustrates a padded back plate for the harness;

FIG. 24 illustrates a back buckle for the harness;

FIGS. 25 to 28 illustrate the use of alternative arrangements of the elastically tethered practice ball apparatus according to the invention;

FIGS. 29 and 30 illustrate two alternative arrangements for attaching the tether to a round ball; and

FIGS. 31 to 34 illustrate arrangements for attaching the tether to an elongate ball.

DETAILED DESCRIPTION OF THE INVENTION

The elastically tethered football apparatus 10 illustrated in FIGS. 1 and 2 is adapted for practising AFL football plays such as, kicking and marking, bouncing on the run and hand balling and retrieving. These plays may be practised at a slow rate or at a fast pace as required to suit the user. To achieve the desired practice play, the harness assembly 12 which is secured to the upper torso of a user, is height adjusted by adjusting the shoulder straps so that the body mount 14 is located substantially centrally at a selected height on the chest of the user, as illustrated.
Referring to FIGS. 3 to 6 in particular, it will be seen that the harness assembly 12 includes a length adjustable chest strap 15 and a pair of shoulder straps 16 and 17 which loop over the chest strap 15 and which may be adjusted to selectively position the height of the chest strap 15 on the user. The chest strap 15 incorporates a clip-together buckle assembly 18 such that the harness assembly 10 may be readily put onto or released from the user. At the rear of the harness assembly 12, the shoulder straps 16 and 17 and the rear parts of the chest strap 15 are interconnected by a back pad 20 so as to distribute the loads applied to the harness assembly 12 more evenly across the back and sides of the user. The backpack 20 may be padded or formed of mesh type material or of other material as desired.
In this embodiment the buckle assembly 18 incorporates the body mount 14 which is formed to receive the prongs 21 of an adjustable strap mounting 22 into accessible cut-outs 19 to releasably secure the chest strap 15 to the user. The prongs 21 when engaged with the body mount 14 extend above and below a central swivel termination 23 which enables the elastic tether 24 to be secured to the body mount 14 such that when tensioned away from the user, the tether 24 is free to rotate irrespective of the angle at which the tensioned tether extends away from the body mount 14 as may occur during normal practice use of the apparatus 10.
For this purpose, as illustrated in cross-section in FIG. 4, the body mount 14 is provided with a central aperture or passage 25 supporting a flanged cylindrical bearing 26 therein such that the cylindrical bearing 26 may rotate freely about it longitudinal axis within the apertures 25. The cylindrical bearing 26 also has a constricted inlet end 27 such that the elastic tether 24, which in this embodiment is formed of hollow elastic tube, may be passed through the constricted inlet 27 and terminated at its end by tying a knot, such as illustrated at 28, so that the tether 24 cannot be withdrawn through the constricted end 27 and wherein the knot 28 is retained within the interior of the cylindrical bearing 26. This ensures that the knotted end does not rub or rotate against the wearer and hinder free rotation of the bearing 26. In this respect the small area of the bearing 26 which may abut the user will not significantly impede rotation of the bearing 26, particularly as the body mount 14 will normally be pulled away from contact with the user's torso when the tether 24 is tensioned. A cover may be utilised to close the rear of the cylindrical bearing 26 to capture the knotted end of the tether within the cylindrical bearing.
The other end of the tether 24 is adapted to be looped over a strop 30 secured to the laced bladder opening 31 of a football 32. In order that the length of the tether 24 may be readily varied to suit the user's requirements, this connection to the strop 30 is formed by bending the tube around the strop 30 and securing the free end part 33 to the adjacent standing part 34 by elastic bands 35 which hold the free part 33 and standing part 34 together. In this arrangement, the elastic bands 35 may be readily slid along the tether 24 to release the free end part 33 whereupon the length of the tether 24 may be adjusted and re-secured by sliding the elastic bands 35 back along the tether 24 and over the end part 33 which is returned against the standing part 34 whereby both the free end part and the standing part are secured to one another without leaving a tail portion to move independently of the tether. Suitably the elastic tether is formed from high tensile latex tubing.
In order that the football 32 may be used in conventional manner when the tether 24 is not secured thereto, the strop 30 is preferably an elastic strop which extends between centrally disposed eyelets 40 and 41 in the opposed lacing portions 42 and 43. The ends of the elastic strop 30 are knotted at the inside of the lacing portions so that the strop 30 is tensioned between the eyelets 41 and 42. This ensures that the elastic strap 30 lies unobtrusively across the join in the opposed lacing portions 42 and 43 and preferably between lacing wraps 44. The elastic strop 30 is formed of elastic material so that it may be readily pulled away from the football to enable the tether 24 to be bent about the strop 30 and secured thereto.
In use, such as is illustrated in FIG. 2, the user dons the harness assembly 12 by adjusting the shoulder straps 17 to position the body mount 14 at the desired height and by tensioning the chest strap 15 so that the body mount is firmly located in position. The tether 24 is then adjusted to length as described above, so that the ball hangs at the desired height or is disposed at the desired distance from the player. If the tether is adjusted to the length as illustrated in FIG. 2, the player may practice kicking and marking, bouncing the football on the run as well as making hand ball passes and retrieving the football from the handball pass. Preferably for handball passing practice the harness and tether is adjusted as illustrated in FIGS. 8 and 9.
It will be seen that the harness assembly 12 for practising the abovementioned plays is positioned on the upper torso/chest area only. However it could be worn around the user's waist so that the user could use the practice apparatus 12 with a round ball for soccer training. Alternatively if the tether is shortened the practice apparatus 10 can be used for netball training, such as for throwing and receiving the tethered ball.
In all of the above plays the provision of the swivel in the tether will enable the rotation imparted to the propelled ball to continue throughout the period the tether is tensioned such that the ball will be received by the user in much the same manner as it would be received by another player to whom the ball was practice propelled, such as by kicking, passing or handballing. This makes for more realistic plays and returns for effective individual training.
Furthermore it is believed that relatively small adjustments to the height of the body mount on a user will enable predictable changes in the retrieval height of the ball to be made, such as when set up for AFL practice, retrieval may be adjusted for retrieval at a standard chest level, or head level, or at higher levels for marking the ball at head level to above the head at arm's length by making small height adjustments such as in the order of 20 mm to 50 mm. Accordingly the practice apparatus may be conveniently used to practice a full range of plays simply by adjusting the height of the chest mount and of course appropriate kicking of the ball which is another important skill to be learnt by the user.
FIG. 7 illustrates an alternate form of harness assembly 50 in which the shoulder straps 51 are adjustably terminated on loops 52 moulded integrally with the body mount 54 and the complementary clip portion 55. This provides a more positive location of the body mount 54 as it is restrained from upward movement by suitable adjustment of the chest strap 56, and downward movement by the shoulder straps 51.
As illustrated in FIGS. 10 to 13, the connection of the tether 24 to a football 32 may also be formed by threading the strop 30 between existing lacing apertures 60 either bridging across the opening 31 as illustrated in FIGS. 10 and 11 or extending diagonally across the opening. Alternatively the strop may extend alongside the opening 31 between apertures 60 at one side of the opening 31. The strop 30 may be disposed symmetrically or asymmetrically along the bladder opening or pairs of strops 30 may be disposed at opposite end portions of the bladder opening and these may be coupled by looping the tether 24 through both pairs of strops all of which may be formed of elastic or non-elastic material as desired.
The first arrangement 53 for securing the tether to the harness illustrated in FIGS. 14 and 15 includes a swivel assembly 57 through with the tether 24 passes. The tether has a ball end 58 extending to the ball and a proximal end 59 extending from the swivel assembly from the proximal end beyond the swivel assembly. A wedge 61 in the form of a resilient frustoconical plug akin to a stopper is tied to the swivel assembly by a tie 62, the wedge being shown in an uninstalled condition in FIG. 14 and wedged into the aperture through which the tether passes being shown in FIG. 15.
The second arrangement 63 for securing the tether to the harness illustrated in FIGS. 16 and 17 has the tether and swivel assembly of FIGS. 14 and 15, but includes a screw 64 screwed radially into the rotatable part 65 of the swivel assembly, the screw being shown separated from the remainder of the apparatus in FIG. 16 and installed in position to lock the tether in place in FIG. 17. The length of the tether is easily adjustable by loosening and retightening the screw.
The third arrangement 66 for securing the tether to the harness illustrated in FIGS. 18 and 19 includes the tether and swivel assembly of FIGS. 14 to 17, but has a spring loaded clamp 67 which may be opened and clamped around the tether at the location selected by the user when determining the length of the tether. The clamp in shown separately in FIG. 18 and is shown installed in FIG. 19. Because the clamp has a size larger than what would pass through the aperture penetrating the swivel assembly, the tether is locked against being pulled through from the ball end. This arrangement has the advantage that the user may pull the tether through the swivel assembly and allow it be lead out when the user kick or hits the ball taking the tether with it. The tether is prevented from being pulled out all the way because of the clamp being installed on the tether in the desired position. The end of the tether can have a knot, knob or plug to prevent the tether from being pulled out of the swivel.
The clip-on swivel 70 for the harness illustrated in FIG. 20 includes an annular swivel assembly 71 with side release clasps 72 for fixing the swivel to the upper chest of a user. The mid-section swivel clip 73 for the harness illustrated in FIG. 21 includes a rectangular swivel assembly 64 for fixing to the mid-section of a user. The fixed strap arrangement 75 for the harness illustrated in FIG. 22 includes a similar arrangement to that illustrated in FIG. 21, except that the straps are fixed, the user donning the harness by pulling it over the head akin to donning a jumper or pull-over.
The padded back plate 76 for the harness illustrated in FIG. 23 includes two upper protuberances 78 and two lower protuberances 79 for receiving waist straps and shoulder straps respectfully. The back buckle 76 for the harness illustrated in FIG. 24 is an alternative to the padded back plate if a user does not need or require the padded version.
The alternative arrangements of the elastically tethered practice ball apparatus according to the invention illustrated FIGS. 25 to 28. In FIG. 25, when tethered to the waist, the apparatus is adapted for different sports by different suggested lengths, being for handball at 80, soccer at 81, baseball or softball fielding at 82, tennis or squash at 83 in FIG. 25. When tethered to the chest harness as shown in FIG. 26, specific skills may be practised, being upper chest pass for football, netball and basketball at 84, handball reflex training for fitness at 85, batting for cricket, hockey, baseball and softball at 86, foot skills for soccer, Australian rules football, rugby and American football at 87, fielding practice for cricket, baseball and softball at 88 and tennis, squash and racquetball at 89. The arrangements for large and small round balls are illustrated in FIGS. 27 and 28.
The two alternative arrangements for attaching the tether to a round ball include a string loop 90 glued to a bladder 91 beneath the skin 92 of the ball 93 as illustrated in FIG. 29 whereas in FIG. 30, the string loop is stitched to the underside of the skin of the ball and such arrangements are suitable for elongate balls as well. In the arrangement shown in FIGS. 31 to 34, the string loop is laced through two or more of the holes 95 in the flange 96 of the valve formation 97 of the bladder. The laces 98 of the ball are threaded through at least two of the holes as well in most arrangements for lacing of the ball.
Pack designs with respect to the swivel will now be described. In one alternative, a separate swivel is built into the pack with side clips to release. In an alternative arrangement, a separate swivel is built into the pack with no side release clips, but instead, a quick fit set-up using a stretch fabric or such like. In a preferred arrangement, a swivel clip is designed to release at the same point of the swivel. The locking of the tether may be at any length to maximize the skill development of the user. The screw-in style hereinbefore describer is provided with a threaded screw which may be tightened against the rubber tether to stop it from moving through the swivel. The clamping style is to stop the tether at any point as hereinbefore described, preferably with rubber-on-rubber clips. The preferred arrangement is the push-in style wedge which is readily insertable and easily pulled out.
Practice apparatus according to aspects of this invention may advantageously utilise all or some of the features described above which has been given by way of illustrative example of the present invention. All such modifications and variations to the inventions set forth above as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of these inventions as is herein set forth.

Claims

1. A tethered practice ball apparatus including:

an elastic tether;

a ball or a ball substitute for a game being practised operatively secured to the elastic tether; and

a harness for securing the tether to a practising athlete, the harness including a body mount forming a termination for the tether and which may be selectively and securely positioned on a user's torso whereby the rebound force vector applied by a stretched tether will direct the returning practice ball toward a selected target on or adjacent the practising athlete.

2. The tethered practice ball apparatus according to claim 1, wherein swivel means is provided between the harness and the ball for dissipating torsional loads which may be induced in the elastic tether.

3. The tethered practice ball apparatus according to claim 2, wherein the swivel means is incorporated in the elastic tether.

4. The tethered practice ball apparatus according to claim 2, wherein the swivel means is incorporated in the mounting to the ball.

5. The tethered practice ball apparatus according to claim 2, wherein the swivel means is incorporated in or adjacent the body mount such that the elastic tether extends only from the swivel to the practice ball.

6. The tethered practice ball apparatus according to claim 5, wherein the swivel means includes a through passage in the body mount through which the tether may extend and be terminated such that it is not restrained from rotating within the through passage.

7. The tethered practice ball apparatus according to claim 7, wherein the tether is terminated within a bearing shell adapted for free rotational location within the through passage.

8. The tethered practice ball apparatus according to claim 1, wherein the harness includes height adjusting means which may be adjusted to selectively position the body mount on a user.

9. The tethered practice ball apparatus according to claim 1, wherein the harness includes one or more an adjustable torso straps which extend directly from the body mount so that in use, the torso strap or straps may be tightened to hold the body mount firmly against a user's torso whereby loads applied by the stretched elastic tether to the body mount may be taken directly by the torso strap or straps.

10. The tethered practice ball apparatus according to claim 9, wherein each torso strap is an assembly of strap portions extending from opposite sides of a back panel.

11. The tethered practice ball apparatus according to claim 10, wherein the ends of the strap portions extending from the assembly terminate by respective opposite side parts of a slide-in clip assembly which forms the body mount.

12. The tethered practice ball apparatus according to claim 11, wherein the slide-in clip assembly has a central receiving part for receiving the opposite side parts and being provided with a substantially centrally disposed swivel mount at which the tether is terminated.

13. The tethered practice ball apparatus according to claim 12, wherein the swivel mount is a through passage supporting a retained rotatable sleeve through which the tether may pass to an enlarged portion which may be constituted by a knot in the tether or other attachment to the tether.

14. The tethered practice ball apparatus according to claim 13, wherein the central receiving part has side recesses therein to receive and secure spaced latching prongs of the respective side parts.

15. The tethered practice ball apparatus according to claim 1, wherein the connection of the tether to the practice ball is a connection formed centrally in the laced bladder opening of a football which is a reinforced part of the football remote from its preferred foot contact zone.

16. The tethered practice ball apparatus according to claim 15, wherein the connection is a releasable connection such that the football may be released and used in conventional play or practice.

17. A method of practising football by securing an elastically tethered football to a user in a manner whereby the tether is adjustably retained on the user for retention at selected positions of the upper torso of the user and adjusting the position of the tether mount such that the rebound force vector applied by a stretched tether will direct the returning practice ball toward a portion of the user's body selected for practising a particular catch.

18. A harness for securing an elastically tethered practice ball to a user, the harness including:

a body mount for securing a tether;

height adjusting means for selectively adjusting the height of the body mount on a user's torso; and

an adjustable torso strap assembly which connects directly to the body mount so that in use, the torso strap assembly may be tightened to hold the body mount firmly against a user's torso.

19. The harness according to claim 18, wherein the body mount includes swivel means for rotatably securing a tether thereto which may include a through passage in the body mount rotatably supporting a hollow retainer in which an enlarged end portion of a tether may be substantially confined for retention therein.

20. A football having a laced bladder opening providing access to the bladder and apertures at opposite sides of a bladder flange, a tether connection being provided by an elastic cord passed through the apertures and tied off so that the elastic cord bridges the bladder opening.