Athletic accessory

An athletic accessory, which serves to permit an athlete normally to bend a jointed limb at will, but, at a critical time, to lock the limb in a fully extended, straight position, such as a bowler's arm during delivery of the ball, comprises two rigid members, a pivot for pivotally connecting the rigid members, supports and straps for attaching the rigid members to the upper and lower limb members of a jointed limb with the pivotal connection coincident with the joint, a sleeve for locking the rigid members together in a straight line, and an internal spring for governing the operation of the locking sleeve to cause the same to lock the rigid members and thus the user's limb in a straight line at the critical time in the athletic endeavor.

BACKGROUND OF THE INVENTION 
In many sports the ability of an athlete to control the movement of his 
limbs is the key to his success. For example, in the sport of bowling, it 
is imperative that the bowler keep his arm straight and elbow locked 
during the delivery of the ball and follow-through after release. Even a 
slight bending of the elbow at this critical time will cause the ball to 
stray from the target. Many bowlers unconsciously, or as a result of a 
distraction, bend their arms during delivery of the ball causing missed 
shots and poor games. Athletes in other sports (e.g. golf, swimming, etc.) 
suffer similar mishaps due to an inability to keep a limb straight at the 
critical time. 
It would be desirable to have a device which permitted an athlete to bend 
his arm or leg at will, but which would, at a critical time, lock the limb 
in a fully extended, straight position. 
SUMMARY OF THE INVENTION 
In accordance with the present invention, an athletic accessory is provided 
having two pivotally connected rigid members strapped to the upper and 
lower limb members of an athlete's jointed limb. The pivot is located 
coincident with the axis of rotation of the athlete's limb joint. Muscular 
extension of the limb causes the rigid members to longitudinally align, 
whereupon a locking means, located on one of the rigid members, which is 
normally held in a dormant position permitting free rotation about the 
pivot, is activated by spring means, or in the alternative by the force of 
gravity, to engage the other rigid member. The rigid members are thereby 
locked in a longitudinally continuous rigid assembly, thereafter 
preventing the athlete from inadvertantly bending the limb. 
Consequently, the athletic accessory of this invention can be of great use 
to an athlete in providing mechanical assistance for controlling the 
movement of a limb. For example, in bowling, the bowler begins his 
delivery by first extending the ball forward and then, while moving 
towards the foul line, the bowler brings the ball backwards in a sweeping 
motion. When the bowler's arm is fully extended at the end of the 
backswing, the locking means of this invention engages, locking the rigid 
members into a longitudinally continuous rigid assembly. The bowler then 
reverses the direction of movement of his arm, bringing the ball forward 
in delivery. The now rigid assembly of this invention holds the bowler's 
arm in a fully extended position, preventing the bowler from bending his 
elbow while delivering the ball and during follow-through. As a result, 
the ball will roll down the alley free from adverse effects which may have 
been caused by the bowler improperly bending his arm. In addition, with 
this problem now solved, the bowler is free to concentrate on other 
aspects of the sport, such as aim, balance and wrist control. 
Consequently, the bowler will bowl with greater skill and accuracy, 
resulting in higher scores. 
Other objects, advantages and features of this invention, and its 
application to other sports will become apparent from the following 
detailed description taken in conjunction with the accompanying drawings.

DETAILED DESCRIPTION 
Referring to the drawings, an upper rigid member 10 is pivotally connected 
to a lower rigid member 12 by a pivotal connection indicated generally at 
14. The rigid members may be fabricated from a rigid, durable, light 
weight material, such as plastic or aluminum in the shape of a rod, bar, 
tube, channel or like configuration capable of resisting forces and 
moments without exhibiting excessive transverse deflections. Each of the 
rigid members 10 and 12 is of a length somewhat shorter than the 
respective limb member to which it is attached, but of sufficient length 
to accommodate means for attaching the rigid member to the limb. 
The pivot connection, indicated generally at 14, may be of any conventional 
construction. The embodiment shown in detail in FIGS. 6-10 illustrates one 
method of constructing the pivot so that a sliding sleeve 24 will slide 
freely over the pivot without snagging. In this embodiment, the connection 
is made by cutting a slot 48 into the lower end of the upper rigid member 
10 and by cutting away from the opposing sides of the upper end of the 
lower rigid member 12 to form a tongue 50 which will fit snugly in the 
slot 48. The tongue 50 is fitted into the slot 48 and a hole is drilled 
through the intersection, normal to the cut surfaces, and a pivot pin 16 
is press fit or otherwise inserted through the hole to form the pivotal 
connection. The pivot pin 16 may be made from the same material as the 
rigid members 10 and 12, or any other suitable material. 
The end of the tongue 50 is rounded to prevent its protrusion beyond the 
limits of the upper rigid member 10 when the members are pivotally 
interconnected, see FIGS. 8, 9 and 10. The lower end of the bifurcated 
portion of the upper rigid member 10 (as formed by the slot 48), indicated 
generally at 42, is also rounded at one side to provide clearance for the 
lower rigid member 12. Part of the inner margin of the bifurcated portion 
of the member 10, indicated generally at 44, is cut at an angle; and parts 
of the member 12, at opposite sides of the tongue 50, indicated generally 
at 46, are similarly cut at a mirror image angle to permit the rigid 
members 10 and 12 to be pivoted in one direction to an acute angle 
relative to one another, as shown in FIG. 8. 
In the opposition direction of pivotal movement, rotation beyond the point 
of longitudinal alignment of the members 10 and 12 is prevented by 
flattened surfaces 38 on the lower ends of the bifurations on the member 
10, which butt against flattened surfaces 40 provided on the member 12, at 
opposite sides of the tongue 50, as shown in FIG. 10. The rigid members 10 
and 12 are therefore permitted to rotate about the pivot 14 from the acute 
angle shown in FIG. 8 to the longitudinally continuous, straight-line 
position shown in FIG. 10, following the sequence illustrated in FIGS. 8, 
9 and 10. 
Means for attaching the two rigid members 10 and 12 to respective limb 
members of a jointed limb preferably comprise a flexible strap 18 and a 
support 20 at the free end of each of the members 10 and 12. These serve 
to firmly but comfortably attach the rigid members 10 and 12 to the 
respective limb members and to retain the same against any substantial 
movement relative to the respective limb member. The supports 20 are used 
to elevate the rigid members 10 and 12 off the athlete's limb to provide 
clearance for a locking means, which is indicated generally at 22. The 
supports 20 also prevent the rigid members 10 and 12 from rotating out of 
position when the device is in use, and contribute to the comfort of the 
user. The strapping means 18 are used to firmly affix the device to the 
athlete's limb so as to prevent the device from slipping out of position 
while in use. 
The supports 20 comprise an end portion 25; a tongue 19 and an elevating 
portion 23 therebetween, and are connected to the ends of the respective 
rigid members 10 and 12 by fitting the tongue 19 of the support 20 into a 
slot cut into the end of the respective rigid member. The connection is 
secured by gluing or welding the support 20 to the respective member, and 
the connection is stiffened and strengthened by reinforcing ribs or struts 
21, which may be molded integrally with the supports 20. The end portions 
25 of the supports 20 are curved to fit snugly against the athlete's limb, 
and together with the straps 18 retain the assembly against movement while 
the device is in use. The elevating portions 23 of the supports 20 elevate 
the rigid members 10 and 12 off the athlete's limb to provide clearance 
for the sleeve 24. The supports 20 may be molded from a light weight 
durable plastic such as poly vinyl chloride or from aluminum. 
The straps 18 may be attached to the end portions 25 of the supports 20 
with mechanical fastenings, by heat sealing, or by gluing. In a preferred 
embodiment, the strap is passed through a slot adjacent one side edge of 
the support 20 and stitched to itself. The straps 18 may be made from any 
conventional strapping material. The straps may be adjusted about the 
user's limb and fastened in any conventional manner, such as coherent 
fasteners, snaps, buckles or other suitable, adjustable fastening devices. 
The rigid members 10 and 12 are adapted to be locked together in 
longitudinal alignment with one another by a locking means, indicated 
generally at 22. In the preferred embodiment, the means 22 is comprised of 
a sleeve 24 slidably mounted on the upper rigid member 10, a stop pin 26 
extending through a bayonet slot 38 in the sleeve which governs the extent 
of slidable movement of the sleeve, and a spring 32 which biases the 
sleeve toward locking position. The sliding sleeve 24 is fabricated from a 
rigid, durable material, such as poly vinyl chloride, aluminum or steel. 
The sleeve 24 has internal surfaces generally complementary to the 
exterior of the rigid members 10 and 12 and has a slidable or slip fit 
thereon. In the embodiment shown, wherein the rigid members 10 and 12 are 
circular rods, the sliding sleeve 24 is preferably a tube having an inner 
diameter slightly greater than the outer diameter of the upper portion of 
the upper rigid member 10. Other configurations may of course be used as 
desired. 
The upper rigid member is formed of one diameter at its upper end and of a 
reduced diameter at its lower end whereby to form a shoulder 34 facing 
toward its lower end within the interior of the sleeve 24. The sleeve 24 
is provided at its lower end with an internal flange or shoulder 36 
opposed to the shoulder 34, whereby the reduced diameter portion of the 
member 10, the sleeve 24 and the shoulders 34 and 36 define a chamber for 
reception of a compression spring 32. The upper end of the spring 32 is 
butted against the shoulder 34 and the lower end thereof is butted against 
the shoulder 36, whereby to bias the sleeve downwardly and to provide the 
motivating force required to thrust the sliding sleeve 24 into locking 
position. Specifically, when the members 10 and 12 are aligned 
longitudinally and the sleeve is released for movement, the spring drives 
the sleeve down over the pivot 14, and into surrounding relationships with 
both of the rigid members 10 and 12, thereby to lock the rigid members 
together in a longitudinally continuous rigid assembly. If the sliding 
sleeve 24 is made of a heavy material such as steel, the spring 32 may be 
omitted in favor of reliance upon gravity and/or centrifugal force to 
provide the motivating force required. 
A vertically disposed bayonet slot 28 with a horizontal slot portion 30 is 
cut through the sliding sleeve 24 to accommodate the stop pin 26 for the 
two-fold purposes of limiting the travel of the sliding sleeve and for 
locking the sliding sleeve in an inoperative or dormant position. The stop 
pin 26 may consist of an ordinary machine screw, screwed into a threaded 
hole in the upper rigid member 12; or may be made from plastic and glued 
into place. The vertical portion of the slot 28 is of sufficient length, 
relative to the location of the screw, to accommodate sliding movement of 
the sleeve 24 from an upper, inoperative position, wherein it is spaced 
above the pivot, to a lower, locked position, wherein it surrounds the 
pivot and engages both of the members 10 and 12. The sliding sleeve 24 may 
be held in the inoperative position by rotating the sliding sleeve 24 so 
that the horizontal slot portion 30 of the bayonet slot receives the stop 
pin 26, whereby the pivot 14 is clear of obstruction and the user may move 
his limb freely. Rotating the sliding sleeve 24 so that the stop pin 26 is 
received in the vertical portion of the slot 28 will activate the locking 
means to "ready" condition. When the athlete thereafter extends his limb 
causing the upper and lower rigid members 10 and 12 to become 
longitudinally aligned, the sliding sleeve 24 will travel over the pivot 
14 and engage the lower rigid member 12. Further movement of the sleeve is 
prevented by reason of the upper margin of the slotted portion of the 
sleeve engaging the stop pin 26. The sliding sleeve 24 is then positioned 
over the pivot 14 thereby preventing rotation of the rigid members 10 and 
12 about the pivot. 
The operation of the device in respect of the sport of bowling is 
illustrated diagrammatically in FIGS. 1 and 2. As shown, the upper rigid 
member 10 is strapped to the user's upper arm and the lower rigid member 
12 is similarly strapped to the user's lower arm, with the pivot 14 
coincident with the axis of rotation of the user's elbow. As the bowler 
approaches the lane, the sliding sleeve 24 is rotated into "ready" 
position with the stop pin 26 engaged in the vertical portion of the slot 
28. (see FIG. 1). The bowler begins, as shown in FIG. 1, addressing the 
lane with his arm bent. Then, while moving toward the foul line, the 
bowler swings the ball down and back in a sweeping motion. When the 
bowler's arm becomes fully extended at the end of the backswing, as shown 
in FIG. 2, the sliding sleeve 24 travels downwardly, by force of the 
spring 32, and passes over the pivotal connection 14 and engages the 
adjacent ends of the two rigid members 10 and 12 respectively, thereby 
locking said rigid members into a longitudinally continuous rigid 
assembly. The bowler then reverses the direction of movement of his arm, 
bringing the ball forward in delivery. The now rigid assembly of this 
invention holds the bowler's arm in a fully extended position, preventing 
the bowler from bending his elbow while delivering the ball and during the 
follow-through of his swing. As a result, the ball will roll down the 
alley free from adverse effects which may have been caused had the bowler 
improperly bent his arm. 
To reset the device, e.g., for rolling the second ball in a frame, the user 
merely pushes the sliding sleeve upwardly to clear the pivot and bends his 
arm (even slightly), thereby to return the device to its "ready" position. 
Between frames, the slide is simply moved upwardly to the extent permitted 
by the vertical portion of the bayonet slot and rotated to dispose the 
stop pin in the horizontal slot portion of the slot, whereupon the device 
is rendered inoperative and the user can bend his arm back and forth in 
normal fashion without hindrance from the device. 
The invention thus provides a highly effective and very economical 
accessory for holding an athlete's limb in an extended position at a 
critical point in an athletic endeavor, without otherwise impairing the 
athlete's participation in the sport. 
While the preferred embodiments of the invention, and a representative mode 
of use thereof, have been illustrated and described herein, it is to be 
appreciated that changes, modifications and variations may be made therein 
without departing from the scope of the invention as defined by the 
appended claims.