Patent US4530206A successfully refreshed from Google Patents.
US4530206A
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Strings for tennis rackets and rackets equipped with same
Assignee: D'EXPLOSIFS ET DE PRODUCTS CHIMIQUES & MAX SIGUIER SA
•
Filing: 1983-09-02
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Granted: 1985-07-23
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Expires: 2003-09-02
Abstract
Abstract A string for a tennis racket and having a composite cross-section structure having a central reinforcing core comprising twisted Kevlar aromatic polyamide and glass yarns or Kevlar aromatic polyamide yarns, this core layer having a peripheral protective coating of a polyamide.
Inventors
- 👤 Alain Benichou
- 👤 Max Siguier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:12
CPC Classifications
D; D07; D07B; D07B1/00; D07B1/16; D07B1/162; A; A63; A63B; A63B51/00; A63B51/02; D02; D02G; D02G3/00; D02G3/22; D02G3/40; D02G3/404; D02G3/44; D02G3/444; D07B1/02; D07B1/025; D07B2201/00; D07B2201/20; D07B2201/2015; D07B2201/2036; D07B2205/00; D07B2205/20; D07B2205/2046; D07B2205/205; D07B2205/30; D07B2205/3003
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
52 words
A string for a tennis racket having a composite cross-section structure having a central reinforcing core comprising twisted Kevlar aromatic polyamide and glass yarns in which the Kevlar/glass yarns are present in a weight ratio of between about 1/1 and 3/1; said core layer having a peripheral protective coating of a polyamide.
Claim 2
Dependent Claim
52 words
A string for a tennis racket having a composite cross-section structure having a central reinforcing core comprising twisted Kevlar aromatic polyamide and glass yarns in which the Kevlar/glass yarns are present in a weight ratio of between about 1/1 and 3/1; said core layer having a peripheral protective coating of a polyamide.
Claim 3
Dependent Claim
22 words
A string as claimed in claim 1, wherein the KEVLAR/glass weight ratio in the twisted yarns comprising the core is around 1/1.
Claim 4
Dependent Claim
66 words
A string as claimed in claim 1, with a core of twisted glass and "KEVLAR" yarns, wherein said string is one of the three presenting the following characteristics: ______________________________________
Weight ratio 50/50 50/50 75/25
KEVLAR/GLASS
coating deposited
Polyamide-6
weight of core
1.23 0.95 0.56
(g/m)
weight of coat-
0.52 0.70 0.34
ing (g/m)
total weight 1.75 1.65 0.90
diameter of 1.42 1.32 0.95
string (mm)
______________________________________
Claim 5
Dependent Claim
126 words
A string for a tennis racket having a composite cross-section structure having a central reinforcing core comprising a group of parallel yarns of Kevlar aromatic polyamide covered with wound Kevlar yarns; said core layer having a peripheral polyamide coating and resulting in a string having one of the following sets of characteristics: ______________________________________
CORE Core of Core of
"KEVLAR 49" "KEVLAR 49"
Count = 5067 dtex
Count = 7800 dtex
Cover in Cover in
"KEVLAR 29" "KEVLAR 29"
Count = 220 dtex
Count = 220 dtex
COATING Polymaide 6 Polyamide 6
Mean diam- 1.28 to 1.30 1.34 to 1.42
eter of
string (mm)
Weight/ 1.40 1.59
meter of
string (g/m)
TENSILE TEST
Drawing speed =
100 mm/minute
Maximum Load
##STR5##
##STR6##
Maximum
##STR7##
##STR8##
Elongation
______________________________________
Claim 6
Dependent Claim
126 words
A string for a tennis racket having a composite cross-section structure having a central reinforcing core comprising a group of parallel yarns of Kevlar aromatic polyamide covered with wound Kevlar yarns; said core layer having a peripheral polyamide coating and resulting in a string having one of the following sets of characteristics: ______________________________________
CORE Core of Core of
"KEVLAR 49" "KEVLAR 49"
Count = 5067 dtex
Count = 7800 dtex
Cover in Cover in
"KEVLAR 29" "KEVLAR 29"
Count = 220 dtex
Count = 220 dtex
COATING Polymaide 6 Polyamide 6
Mean diam- 1.28 to 1.30 1.34 to 1.42
eter of
string (mm)
Weight/ 1.40 1.59
meter of
string (g/m)
TENSILE TEST
Drawing speed =
100 mm/minute
Maximum Load
##STR5##
##STR6##
Maximum
##STR7##
##STR8##
Elongation
______________________________________
Claim 7
Dependent Claim
13 words
A string as claimed as claim 2 wherein the peripheral coating is polyamide-6.
Claim 8
Dependent Claim
13 words
A string as claimed in claim 1 wherein the peripheral coating is polyamide-6.
Claim 9
Dependent Claim
13 words
A string as claimed in claim 2 wherein the peripheral coating is polyamide-12.
Claim 10
Dependent Claim
13 words
A string as claimed in claim 1 wherein the peripheral coating is polyamide-12.
Claim 11
Dependent Claim
30 words
Tennis rackets, of the type with large stringing, stretched to about 30 kg, wherein said rackets are equipped with strings as claimed in any one of claims 1 to 8.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-22 | 1989-01-21 | 1989-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-22 | 1993-01-21 | 1993-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-22 | 1997-01-21 | 1997-07-23 | $7700.00 | Window Closed / Lapsed |