# US 8,540,584 B1 · Swing speed trainer

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- Number: US 8,540,584 B1
- Document ID: US8540584B1
- Status: Granted
- Kind: B1
- Application number: 12/930,067
- Filed: 2010-12-27
- Granted: 2013-09-24
- Earliest claimed: 2010-12-27
- Applicants: James W. Sorenson
- Inventors: James W. Sorenson
- Web page: https://patentgrep.com/patent/US8540584B1

## CPC

- A63B 69/0002: {for baseball}
- A63B 15/00: Clubs for gymnastics or the like {, e.g. for swinging exercises}
- A63B 15/005: {with a weight movable along the longitudinal axis of the club due to centrifugal forces}
- A63B 60/04: Movable ballast means {(A63B15/005 takes precedence)}
- A63B 69/36: for golf
- A63B 69/38: for tennis {(A63B61/006, A63B69/0073 and A63B69/0097 take precedence)}
- A63B 2069/0008: {for batting}
- A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H)

## Abstract

An athletic swing trainer permits an athlete to swing a trainer at speeds far in excess of the athlete's conventional swing speeds and to confirm to the athlete that the practice swings made with the trainer at these extremely high speeds have been technically properly executed. Armed with this experience, the athlete is then able to swing the athlete's own conventional club, bat or racquet at speeds which, though lower than the athlete's trainer swing speeds, are significantly higher than the athlete's conventional club swing speeds. After six or seven trainer swings, an athlete's swing speed at point of contact of a conventional golf club, bat or racquet with a corresponding ball is typically increased in a range of 5 to 15%.

## Claims

### Claim 1

A golf swing speed trainer comprising:
a straight shaft having a golf grip on an upper end of said shaft, said shaft being sufficiently rigid to maintain its straightness with a slight static bow when the trainer is held by said grip in a stationary horizontal position and sufficiently flexible to elastically deform to a greater dynamic bow when the trainer is held by said grip and swung;
a cap on a lower end of said shaft;
a spherical weight slidable on said shaft between said grip and said cap; and
means for holding said weight in an upper position on said shaft and for releasing said weight from said upper position to centrifugal force generated during a downswing of the trainer to strike against said cap at substantially a ball striking position of the trainer.

### Claim 2 (depends on 1)

A trainer according to claim 1, said static bow having a deflection in a range of 1.75 to 2.75% of a length of said shaft.

### Claim 3 (depends on 1)

A trainer according to claim 1, said dynamic bow having a maximum deflection in a range of 30-40% of a length of said shaft.

### Claim 4 (depends on 1)

A trainer according to claim 1, said static bow having a deflection in a range of 1.75 to 2.75% of a length of said shaft and said dynamic bow having a maximum deflection in a range of 30-40% of said length of said shaft.

### Claim 5 (depends on 1)

A trainer according to claim 1, said shaft elasticity and said weight being coordinated to produce a “swoosh” sound when the trainer is swung with a correct golf swing at a high speed.

### Claim 6 (depends on 1)

A trainer according to claim 1, said holding means comprising a first member fixed on the trainer proximate a lower end of said grip and a second member fixed to said weight, said member having a force of magnetic attraction therebetween holding said weight in said upper position.