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US4003572A Expired / Lapsed US ⏱️ 0.0 years remaining

Home tennis practice contrivance

Assignee: Individual
•
Filing: 1975-04-28
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Granted: 1977-01-18
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Expires: 1995-04-28
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Abstract

Abstract An inflatable and deflatable thin-walled bag resembling a toy balloon is adapted to be suspended from an overhead support by an elongated flexible filamentary member, such as a cord, by an attachment device, such as an adhesive strip. The length of the cord is adjustable by an adjusting device to position the bag at the desired height for the particular stroke intended to be practiced. A sharp stroke from the tennis racquet causes the air-filled bag to fly at a decreasing speed rapidly away from the racquet, but to return much more slowly because of the effect of its light weight combined with the resistance of the air upon it. Due to the effect of this rapid retardation on the return flight of the bag, the user is given sufficient time, even after making a full follow through, to enable him or her to assume the proper stance for the next practice stroke according to the height of the bag above the floor or ground level. BACKGROUND OF THE INVENTION The prior art shows numerous examples of tether balls, such as tennis balls or baseballs suspended by cords from overhead supports. However, each of these prior tether balls is a comparatively heavy object which, upon being hit by a racquet or bat, is propelled at high speed through a long forward path and returns at high speed over a long return path much more rapidly than the toy-balloon-like light-weight thin-walled inflated bag of the present invention, with the result that air resistance has very little effect upon retarding the return velocity of the prior heavy tether balls. Furthermore, these prior devices, because of their heavy weights and high speed, cannot safely be used indoors in a home because of the damage they would do to objects encountered in their path. The prior art also discloses a resiliently-deformable polyurethane foam tube adapted to be suspended by a cord from an overhead support and propelled back and forth between two players equipped with bats. Experience with the present invention has shown that repeated blows upon one of the polyurethane foam objects causes the object to disintegrate quickly by its repeated sharp contacts with the taut lattice-like stringing of a tennis racquet. SUMMARY OF THE INVENTION The invention primarily resides in the provision of an elastomeric thin-walled light-weight inflatable and deflatable bag, like a toy balloon, suspended by an elongated flexible filamentary member, such as a cord, from an overhead support, such that the speeds of the forward and return flights of the bag are so greatly retarded by the air resistance that it almost halts when it reaches the player. The toy-ballon-like thin-walled deflated bag is thin and flat, hence is easily packed, shipped, stored and carried by the player in a compact low-cost flat container, such as an envelope, and is quickly and easily inflated by the mouth of the player upon reaching home or other practice location, where it is to be used. Advertising matter can also be imprinted upon the bag.

Inventors

  • 👤 Louis A. Harvey

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 18:08
CPC Classifications
A; A63; A63B; A63B69/00; A63B69/0073; A63B69/0079

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 223 words
A home-tennis practice contrivance comprising an elongated flexible substantially inextensible filamentary suspension member having a main suspension portion with a pivot portion at its upper end adapted to be connected to an overhead support and having a reversely-directed surplus portion depending from said pivot portion, an inflatable and deflatable toy-balloon-like bag of elastomeric material having a tubular inflation neck portion projecting upward therefrom and adapted to be constricted in air-retaining relationship to said bag and connected to the lower end of said main suspension portion of said suspension member, said bag when inflated being of spheroidal shape and of substantially the size of a conventional tennis ball, said bag when deflated being of limply-drooping vertically-elongated shape, said bag in response to impact with a tennis racquet travelling upon a forward flight at relatively high speed and upon a return flight at a greatly retarded speed in response to the decelerating effect of air resistance upon the bag. ; and an attachment device connected to said pivot portion of said suspension member and having an adhesive layer thereon adapted to be adhesively secured to the overhead support, said reversely-directed surplus portion having a suspension member length adjuster consisting of a cord-retaining slider containing an aperture and connected to the lower end of said surplus portion and slidably engaging and encircling said main suspension portion.
Claim 2
Dependent Claim 223 words
A home-tennis practice contrivance comprising an elongated flexible substantially inextensible filamentary suspension member having a main suspension portion with a pivot portion at its upper end adapted to be connected to an overhead support and having a reversely-directed surplus portion depending from said pivot portion, an inflatable and deflatable toy-balloon-like bag of elastomeric material having a tubular inflation neck portion projecting upward therefrom and adapted to be constricted in air-retaining relationship to said bag and connected to the lower end of said main suspension portion of said suspension member, said bag when inflated being of spheroidal shape and of substantially the size of a conventional tennis ball, said bag when deflated being of limply-drooping vertically-elongated shape, said bag in response to impact with a tennis racquet travelling upon a forward flight at relatively high speed and upon a return flight at a greatly retarded speed in response to the decelerating effect of air resistance upon the bag. ; and an attachment device connected to said pivot portion of said suspension member and having an adhesive layer thereon adapted to be adhesively secured to the overhead support, said reversely-directed surplus portion having a suspension member length adjuster consisting of a cord-retaining slider containing an aperture and connected to the lower end of said surplus portion and slidably engaging and encircling said main suspension portion.

References Cited (Backward Citations)

US700850A Cited
US811546A Cited
US2045972A Cited
US3643948A Cited
US3646887A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-01-18 1980-07-19 1981-01-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-01-18 1984-07-19 1985-01-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-01-18 1988-07-19 1989-01-18 $7700.00 Window Closed / Lapsed

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