Speed indicating apparatus

Abstract

A speed indicating system useful in training an athlete includes a spool on which a tether line is wound with the free end thereof then secured to the body of the athlete, any selected one of the athlete's limbs, or any object swung, kicked or thrown by the athlete. The spool includes one or more permanent magnet pieces mounted on its periphery in an alignment adjacent an inductive pickup coil which then communicates the current level induced to a meter indicating the tether line deployment rate. The reverse electromotive force resulting from the inductive coupling is then useful to reduce the inertially driven tether line deployment.

Description

REFERENCE TO RELATED APPLICATIONS

This application obtains the benefit of the earlier filing date of U.S. Provisional Application Ser. No. 61/202,528 filed on Mar. 10, 2009.

BACKGROUND OF THE INVENTION

1. Field of the Invention:

The present invention relates to apparatus for sensing the movement of the the whole or portions of the body of an athlete, or any sports object moved thereby, and more particularly to a measurement system in which the rate of deployment of a flexible tether line from a rotary spool provides an observable measurement useful in training.

2. Description of the Prior Art:

The course of training an athlete often entails many measurements that are taken either for positive reinforcement of desired body movement or as an indication of improper habits. In each instance it is not the absolute value of the measurement but its trend over time that provides the significant information to the trainer and for these reasons simple and therefore reliable mechanisms are preferred over the more elaborate ones. These same measurements may be also associated with various mechanisms that impose a load or resistance on the athlete such as those described in my prior U.S. Pat. Nos. 5,197,931 and 6,652,427 issued respectively on Mar. 30, 1993 and Nov. 25, 2003.

Along with my foregoing training resistance mechanisms various other tethering implementations have been devised in the past which, in one way or another, either pull the tethered athlete to higher effort levels, or resist his or her movement, as a part of the training. Examples of such prior art teachings can be found in U.S. Pat. Nos. 4,469,324 to Dolan, 5,427,394 to Michaelson, 6,053,850 to Martinez et al., 6,123,649 to Lee et al., 6,149,559 to Mackey, and many others. In each instance the tension levels in the foregoing tethering mechanisms serve as the resistive force opposing the movement of selected parts of the athlete's musculature and these relatively high tension levels keep the tether line taut.

Those skilled in the art, however, have noted that the development of a particular muscular group alone does not necessarily result in a superlative performance of a particular athletic endeavor. Thus, for example, the development of leg musculature does not necessarily result in the lowest time sprints since the coordinated movement of the whole body is entailed. The training regimen, therefore, needs to replicate more closely the whole of the particular athletic endeavor such as the starting lunge in a sprint, the swing of a bat, and the like. The repetitive training of these more complex movement sequences, however, entail much closer attention to the whole body movement that resolves itself in acceleration and velocity profiles, and it is the immediate feedback of this information, rather than any force or tension feedback, that best serves the training of this more complex whole body endeavor.

Heretofore the complex mass distribution, inertia, elasticity and aerodynamic components of a tether line have limited its use to what are essentially these highly stressed, steady state applications. Simply, the dynamic response of a free tether line rarely matches the accelerations and decelerations of a complex body movement, leaving whole lengths of the tether as freely undulating loops that either interfered with the athlete's motions or even confuse them.

Thus the use of tethers has been deferred to uses that create resistance to a confined movement as clearly illustrated by the rich variety of this theme in the prior art and even though the manifest simplicity of a tether line offers highly desirable benefits as a measurement mechanism the associated burden of loose lengths of string flying around has discouraged all efforts at combining the tether with signal producing mechanisms Thus measurement systems utilizing a tether haves had little development in the past even while being particularly useful in applications where continuous, or analog, measurements of whole body motion are needed. It is therefore the novel adaptation of the tether line into a continuous measurement system that I now describe.

SUMMARY OF THE INVENTION

Accordingly, it is the general purpose and object of the present invention to conform the deployment of a tether line from a spool as a measurement mechanism wherein the measurement of its rate of deployment also serves as a negative feedback to dissipate the momentum stored.

Other objects of the invention are to provide a measurement system in which the signal indicating a rate of change acts also to attenuate the inertia induced deployment of the measuring mechanism, thereby rendering it less obtrusive.

Yet additional and further objects of the invention shall become apparent upon the inspection of the description that now follows, in conjunction with the accompanying illustrations.

Briefly, these and other objects are accomplished within the present invention by mounting on a base a freely rotating spool on which a length of tether string or webbing is wound with the base then positioned and secured adjacent the starting place of the athletic endeavor. Once thus aligned, the free end of the tether webbing is attached to the body or limb of the athlete whose movement is to be measured, or alternatively to the sports device like a bat, racquet, ball or golf club held, kicked or thrown, to be unwound from the spool by the lunge, jump or swing by increments and rates that correspond to the motion.

One or more magnetized pieces fixed to the periphery of one of the two coaxial end discs, or wheels, defining the spool are then advanced across a set of pickup coils at a rate corresponding to the deployment of the tether webbing, generating an electrical current sensed by a meter containing a galvanometer movement with the meter deflection then corresponding to the rate of tether deployment. In this manner a measurement indication is obtained that corresponds directly to the rotation rate of the spool which, in turn, corresponds to the movement rate of the body, limb, sports device or ball that is tied to the free tether end, providing the athlete a visual feedback.

Of course, the same current that is induced in the pickup coil to drive the meter also generates a correspondingly opposing electromotive force (back EMF) against the rotation of the wheel, thus opposing any further unwanted deployment of the tether resulting from the stored spool rotary momentum to reduce the incidence of the unwanted loose ribbon coils. The inventive measurement system thus elegantly dissipates these inertial effects within the measurement process itself to provide a more accurate indication of the athlete's performance while also limiting the deployment of unwanted tether coils that may confuse the measurement, or even hinder the athletic exercise. As result a simple, and therefore reliable, measurement system is provided which is particularly useful for comparative training.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view illustration of the inventive speed indicating system connected to an athlete in the course of starting a spring from the starting blocks of a track circuit;

FIG. 2 is a rear perspective illustrations of the inventive speed indicating system deployed for use;

FIG. 3 is yet another perspective illustration, separated by parts, of the inventive speed indicating system; and

FIG. 4 is a further diagrammatic rear perspective illustrations of an alternative manners of retaining the inventive speed indicating system in a setting like at the site of a swimming pool where impervious ground surfaces are entailed.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As shown in FIGS. 1 through 4 the inventive speed indicating system generally designated by the numeral 10 is defined by a substantially flat base frame 11 provided with a vertical pivot post 12 on which a spool carrier assembly 20 is pivotally mounted. Base frame 11 may be fixed in its position on the ground G either by spikes 14 driven into the ground through securement holes 16 at the frame corners, or may be held in place by weight bags 16B, as illustrated in FIG. 4, when the athletic exercise takes place on a concrete or otherwise impervious surface IS. Both these modes of securement restrain the base assembly 11 in place while the free end of a tether line or webbing 25 stored on a spool 21 mounted for rotation on a pin 22P bridging across a cage 22 defining the carrier assembly 20 is tied to the athlete AT, or to an object swung, kicked or thrown by the athlete AT (not shown).

Preferably the spool carrier assembly 20 includes a vertically aligned pivot bore 23 formed in a pivot tube 24 fixed to one edge of carrier frame 22 in which the vertical post 12 is received, allowing some freedom of pivotal motion of the spool carrier assembly 20 as the webbing 25 is deployed from the spool through an opening 26 in a guide structure 27 cantilevered from the other edge of the cage, thus continuously aligning the assembly along the proper azimuth towards the athlete. One of the two end discs 29 defining spool 21 is then provided with one or more spaced magnetized pieces 28 radially spaced to pass adjacent a pickup coil 31 that is connected to a meter 30 to drive its movement by the current induced by the spool rotation.

Those skilled in the art will appreciate that the current induced in coil 31 by the spool rotation will inherently produce an opposing electromotive force, sometimes referred to as back EMF, that acts in a direction opposite to the spool rotation as illustrated by the arrow EMF in FIG. 2. Thus as the athlete AT engages in a lunge or jump, as illustrated by the prospective dive from the starting platform SP at a swimming event illustrated in FIG. 4, a following arcuate loop AL of the webbing 25 is formed which then abruptly ends upon the athlete's water entry. Consequently, unless some restraint is provided on this excess webbing deployment loose coils thereof will accumulate on the water surface to interfere with the athletic exercise.

Of course, similar loose lengths of webbing will accumulate as the athlete AT leaves the starting blocks SB of a field track event illustrated in FIG. 1, primarily as a consequence to the athlete's initial velocity transient which thereafter settles to a steady state level that is often lower than the initial state. Notably, these transients coincide with the expenditure of great levels of force by the athlete and the small restraint posed by the tug of the inherent back EMF result in little interference that is hardly perceptible.

More importantly, this opposing electromotive force increases with the spool rotation rate coinciding with the time when loose lengths of the webbing on the exercise surface would create most distraction but not at the time of the initial transient that is most significant in any training measurement. Thus the inventive speed indicating system elegantly resolves the many competing interests that arise in any arrangement suited for training. Simply, as will be apparent to those skilled in the art, a training athlete ordinarily has a keen interest in any contemporaneous measurement indication, which ordinarily entails some significant current levels driving any measurement display, while the same current levels are also inventively utilized in the instant invention to avoid any interfering clutter.

Moreover, the simple instant resolution of these competing interests is particularly useful in a setting where less attention is likely to be paid to the measuring device while all focus is directed on the athlete. Thus the simplicity of this arrangement renders a robust, easily understood and therefore easily used mechanism that avails clear notice when a problem has occurred.

Obviously many modifications and variations of the instant invention can be effected without departing from the spirit of the teachings herein. It is therefore intended that the scope of the invention be determined solely by the claims appended hereto.

Claims

1. Apparatus for measuring the movement rates of an athlete, comprising in combination:

a support assembly conformed for a restrained positioning upon a ground surface;

a spool mounted for rotation on said support assembly including a flexible tether wound thereon conformed for attachment of the free end thereof to said athlete;

magnetized means attached to said spool for movement according to the rotation thereof;

sensing means mounted on said support assembly for deploying an inductive coil adjacent the movement of said magnetized means for producing an induced current indicative of said movement, whereby said induced current in said induction coil imposes an reverse electromotive force on said magnetized means; and

measurement means connected to receive said induced current for providing an indication of the magnitude thereof.

2. Apparatus according to claim 1, wherein:

said support assembly includes a base frame selectively securable to said ground surface.

3. Apparatus according to claim 2, wherein:

said support assembly further includes a cage supporting said spool pivotally mounted on said base frame.

4. Apparatus according to claim 3, wherein:

said cage includes a guide aperture for receiving in translation said flexible tether and is pivotally mounted on said base frame at a pivot axis generally orthogonal thereto.

5. Apparatus according to claim 4, wherein:

said flexible tether comprises webbing.

6. A speed indicating system useful in training athletes, comprising in combination:

a generally planar supporting base conformed for positioning upon a ground surface including a generally vertical pivot shaft;

a spool assembly mounted for rotation about said pivot shaft including a rotary spool carried thereon and having flexible webbing wound thereon;

magnetized means attached to said spool for movement with the rotation thereof; and

sensing means mounted on said support assembly for deploying an inductive coil adjacent the movement of said magnetized means for producing an induced current indicative of said movement, whereby said induced current in said induction coil imposes an reverse electromotive force on said magnetized means.

7. Apparatus according to claim 6, further comprising:

a meter connected to receive said induced current for providing a visual indication of the magnitude thereof.

8. Apparatus according to claim 7, wherein:

said support assembly includes a base frame selectively securable to said ground surface.

9. Apparatus according to claim 8, wherein:

said spool assembly includes a guide aperture for receiving in translation said flexible tether webbing.

10. Apparatus according to claim 9, wherein:

said magnetized means includes a plurality of permanent magnets.

11. Apparatus according to claim 6, wherein:

the rotary axis of said spool is generally orthogonal to said pivot shaft.

12. Apparatus according to claim 6, further comprising:

a meter connected to receive said induced current for providing a visual indication of the magnitude thereof.

13. Apparatus according to claim 12, wherein:

said support assembly includes a base frame selectively securable to said ground surface.

14. Apparatus according to claim 13, wherein:

said spool assembly includes a guide aperture for receiving in translation said flexible tether webbing.