31
William J Balka Jr: Automatic ball server. H Hume Mathews, June 17, 1980: US04207857 (67 worldwide citation)

Automatic ball serving apparatus for serving, lobbing, volleying or smashing balls, such as tennis balls, for practice purposes wherein two cans or buckets are vertically stacked to form a lower generally cylindrical compressed air chamber and an upper generally cylindrical ball feed chamber, a ball ...


32
Thomas J Walls: Multi-sport exerciser. John H Calhoun Jr, May 11, 1982: US04328964 (66 worldwide citation)

An apparatus for exercising and developing the muscles used in certain athletic endeavors comprising a plurality of elastic ropes, means for anchoring one end of each elastic rope to a stationary object, a plurality of handles made to conform in size, shape and construction to handles commonly used ...


33
Hiroshi Matsumura, Koji Nii: Grip tape. Asahi Kagaku Kogyo, Lowe Price Leblanc & Becker, October 8, 1991: US05055340 (66 worldwide citation)

A grip tape for wrapping the gripping handle of a tennis racket, a badminton racket, a golf club, or the like which includes a porous flexible sheet with numerous thin holes provided by coating a polyurethane on a nonwoven fabric so as to provide the user with various effects such as a smooth touch ...


34
Bobby V Hundley: Dual compartment food tray. Emrich & Dithmar, January 17, 1995: US05381901 (65 worldwide citation)

A nestable food or snack tray having a pair of recessed food storage compartments each adapted to receive and hold food is vacuum molded from a single sheet of lightweight plastic, such as polystyrene. A first recessed compartment is shaped in the form of an athletic field or stadium such as a tenni ...


35
Bruce W Harrell: Detachable shoe-pocket system. John F McClellan Sr, April 2, 1985: US04507882 (62 worldwide citation)

A quick-attach, quick-detach shoe accessory in the form of a container for carrying keys, rings, paper money, coins and like items on the instep of a tennis shoe or other lace type shoe, has a sheath-like body with open top end with a covering flap and closed bottom and pleated sides securable to a ...


36
Tranfield George: Pile fabric method and product. Chas W House & Sons Incorporated, August 15, 1972: US3684284 (62 worldwide citation)

A pile fabric designed particularly for use as a cover of a tennis ball. The fabric has a base structure comprising knitted cotton yarns, preferably in two layers laid back-to-back. A pile surface is provided on one side of the base structure by a fleece preferably composed of a plurality of carded ...


37
Donald O Fareed: Forearm transaxial compression band. Michael G Petit, October 6, 1992: US05152302 (61 worldwide citation)

An adjustable strap or band adapted to be circumferentially fitted around the forearm to alleviate the symptoms of tennis elbow. The strap is a generally band-shaped device having opposing inwardly protruding means on its forearm contacting surface to direct transaxial compression against the radial ...


38
Green Wallace V: Automatically operated spring-type projectile projecting device. October 5, 1971: US3610223 (61 worldwide citation)

A tennis ball launcher described wherein one ball at a time is selected from a hopper containing a supply of balls and positioned in a ball feed mechanism on a pair of spaced parallel supports. A mounted rotatable cylinder through which the balls pass from the hopper to the ball feed assembly has a ...


39
Jerry A Nuttall: Method and apparatus for radar measurement of ball in play. Matrix Engineering, Cahill Sutton & Thomas, August 11, 1992: US05138322 (60 worldwide citation)

A system for continuously and precisely measuring the positions of a generally symmetrical object, e.g., a tennis ball, in motion in a predefined three-dimensional region, e.g., a tennis court, which transmits multiple radar signals from first, second, and third, spaced antenna devices, respectively ...


40
Samuel F Stewart: Racket weighting means. Lee & Smith, October 4, 1977: US04052061 (59 worldwide citation)

An improved racket weighting device for use with any existing racket having a shaft with a throat connected to a frame during warm-up, practice or actual play in sports such as tennis, badminton, squash or the like. The device includes a non-continuous flexible member adapted to be wrapped at least ...