Patent US4197570A successfully refreshed from Google Patents.
US4768786A
Expired / Lapsed
US
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Tennis racket
Assignee: Individual
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Filing: 1987-02-24
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Granted: 1988-09-06
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Expires: 2007-02-24
Abstract
Abstract A racket, for playing a game using a ball of limited resiliency, such as a tennis racket comprises a racket head frame portion provided with stringing, a handle, and a shaft arrangement connecting the racket head frame portion and the handle. The resonance frequency of the racket head frame portion at least approximately corresponds to the period of time for which a ball is in contact with the strings of the racket when struck thereby, and the natural frequency or oscillation frequency of the racket substantially corresponds to the excitation frequency of the ball. The thickness of the racket frame as measured in a direction normal to the plane of the stringing is greater than the thickness of the handle as measured in a corresponding direction.
Inventors
- 👤 Siegfried Kuebler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:42
CPC Classifications
A; A63; A63B; A63B49/00; A63B49/02; A63B49/10; A63B2049/0211; A63B60/00; A63B60/002
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
155 words
A tennis racket, for use with a ball of limited resiliency, having a longitudinal axis which comprises: a handle; a frame portion including a frame member having an annular opening, stringing on said frame member covering said annular opening, shaft members depending from the frame member and including a transition from the shaft members to the handle, a throat member extending between the shaft members and forming a base of said annular opening, said throat member and said shaft members defining a throat region, said handle being connected to the shaft members in the longitudinal axis of the racket forming a straight line of symmetry, wherein the cross-sectional height of said frame portion as measured in a direction perpendicular to the plane of the stringing is greater than the parallel thickness of said handle; and wherein the oscillation frequency of said frame portion substantially corresponds to the excitation frequency of a standard new tennis ball.
Claim 2
Dependent Claim
155 words
A tennis racket, for use with a ball of limited resiliency, having a longitudinal axis which comprises: a handle; a frame portion including a frame member having an annular opening, stringing on said frame member covering said annular opening, shaft members depending from the frame member and including a transition from the shaft members to the handle, a throat member extending between the shaft members and forming a base of said annular opening, said throat member and said shaft members defining a throat region, said handle being connected to the shaft members in the longitudinal axis of the racket forming a straight line of symmetry, wherein the cross-sectional height of said frame portion as measured in a direction perpendicular to the plane of the stringing is greater than the parallel thickness of said handle; and wherein the oscillation frequency of said frame portion substantially corresponds to the excitation frequency of a standard new tennis ball.
Claim 3
Dependent Claim
31 words
A racket according to claim 1 wherein the frame portion thereof is produced from a strip-like blank having longitudinal edges, wherein a string member runs along each of said longitudinal edges.
Claim 4
Dependent Claim
16 words
A racket according to claim 2 wherein said frame portion comprises a fiber material with resin.
Claim 5
Dependent Claim
25 words
A racket according to claim 2 wherein said strip-like blank has narrow sides and longitudinal edges within a flexible tube and including an interior member.
Claim 6
Dependent Claim
23 words
A racket according to claim 2 wherein said strip-like blank includes a multilayer lap member, wherein said string members run between lap layers.
Claim 7
Dependent Claim
21 words
A racket according to claim 2 wherein said string member is selected from the group consisting of fiber, metal and ceramic.
Claim 8
Dependent Claim
27 words
A racket according to claim 1 wherein said frame member has an elongated generally oval cross-section, with at least one longitudinal wall thereof forming a groove-like indentation.
Claim 9
Dependent Claim
18 words
A racket according to claim 7 including a collar and a conduit crosspiece seated in said groove-like indentation.
Claim 10
Dependent Claim
49 words
A racket according to claim 1 wherein it is of its maximum height as measured in a direction normal to the plane of said stringing in said throat region and tapers both towards said handle and towards the end of said frame portion which is remote from said handle.
Claim 11
Dependent Claim
11 words
A racket according to claim 9 wherein said taper is progressive.
Claim 12
Dependent Claim
20 words
A racket according to claim 9 including a region of maximum height extending on both sides of said throat region.
Claim 13
Dependent Claim
52 words
A racket according to claim 1 having an open throat region which is limited by sections of the shaft member meeting towards the handle and by a throat member connecting said sections on the frame portion, wherein the height of the throat member is smaller than the height of the shaft member.
Claim 14
Dependent Claim
26 words
A racket according to claim 12 wherein the cross-section of the greatest height of the shaft member are provided on both sides of the throat member.
References Cited (Backward Citations)
FR962312A
Cited
GB415707A
Cited
FR827983A
Cited
US2171223A
Cited
US3809402A
Cited
US3647211A
Cited
US3640533A
Cited
DE2228245A1
Cited
USD243467S
Cited
US4291574A
Cited
US4070020A
Cited
JPS5385634A
Cited
US4440392A
Cited
US4293129A
Cited
US4322076A
Cited
US4438925A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-06 | 1992-03-07 | 1992-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-06 | 1996-03-07 | 1996-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-06 | 2000-03-07 | 2000-09-06 | $7700.00 | Window Closed / Lapsed |