Patent US4935185A successfully refreshed from Google Patents.
US4935185A
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US
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Method of making a fibre-reinforced molded racquet frame
Assignee: DP ACQUISITION Inc
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Filing: 1988-10-24
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Granted: 1990-06-19
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Expires: 2008-10-24
Abstract
Abstract A method of making a fibre-reinforced molded racquet frame is disclosed. The method comprises placing two cores each including a respective tube having at least one layer of woven reinforcing fibres in a mold shaped to define the frame. A respective core is positioned on each side of the split-line of the mold. A plurality of string-securing members are formed with each string-securing member comprising a first portion shaped to receive and position at least one string of stringing to be secured in the frame and a second portion adapted to be embedded in the frame. The string-securing member is supported such that, upon closure of the mold, the second portions are disposed inside the mold cavity and entrapped between the two cores while the first portions project out of the mold cavity into the area which will be surrounded by the mold frame. A plastics material is injected into the mold around the cores and the second portions of the string-securing members. The plastics material preferably has a relatively low setting temperature and a relatively low viscosity.
Inventors
- 👤 Jonathan C. Mott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:56
CPC Classifications
A; A63; A63B; A63B49/00; A63B49/02; A63B49/10; B; B29; B29C; B29C70/00; B29C70/04; B29C70/28; B29C70/40; B29C70/42; B29C70/46; B29C70/48; A63B49/11; A63B60/00; B29C70/68; B29C70/86; B29C70/865; A63B2049/0205; A63B2049/103; A63B2209/00; A63B2209/02; A63B2209/023; B29K; B29K2033/00; B29K2033/04; B29L; B29L2031/00; B29L2031/52; B29L2031/5245
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
319 words
A method of making a fibre-reinforced molded racquet frame, the method comprising the steps of: forming two separate cores each including a respective tube having at least one layer of woven reinforcing fibres; forming a mold cavity within a mold in the shape of the racquet frame with a first portion of the mold cavity formed in an upper mold plate and a second portion of the mold cavity formed in a lower mold plate; placing one of the cores in the first portion of the mold cavity in the upper mold plate and placing the other of the cores in the second portion of the mold cavity in the lower mold plate with opposing surfaces of the cores facing one another; forming a plurality of string-securing members with each string-securing member comprising a first portion in the form of a loop and a second portion in the form of an anchorage connected to the loop, the loop being shaped to receive and position at least one string of stringing in the area between the loop and the inside surface of the molded frame; placing, while the first and second mold plates are separated, the second portion of each string-securing member in a position overlying the opposing surfaces of the cores with the first portions of each string-securing member projecting out of the mold cavity into the area which will be surrounded by the molded frame; closing the mold to place the opposing surfaces of the separate cores into contact with one another and into contact with the second portions of the string-securing members; injecting a plastics material into the mold around the cores and the second portions of the string-securing members; allowing the plastics material to harden in the mold cavity to form to the molded racquet frame; and removing the molded racquet frame formed of the cores, hardened plastics material and string-securing members from the mold cavity.
Claim 2
Independent Claim
319 words
A method of making a fibre-reinforced molded racquet frame, the method comprising the steps of: forming two separate cores each including a respective tube having at least one layer of woven reinforcing fibres; forming a mold cavity within a mold in the shape of the racquet frame with a first portion of the mold cavity formed in an upper mold plate and a second portion of the mold cavity formed in a lower mold plate; placing one of the cores in the first portion of the mold cavity in the upper mold plate and placing the other of the cores in the second portion of the mold cavity in the lower mold plate with opposing surfaces of the cores facing one another; forming a plurality of string-securing members with each string-securing member comprising a first portion in the form of a loop and a second portion in the form of an anchorage connected to the loop, the loop being shaped to receive and position at least one string of stringing in the area between the loop and the inside surface of the molded frame; placing, while the first and second mold plates are separated, the second portion of each string-securing member in a position overlying the opposing surfaces of the cores with the first portions of each string-securing member projecting out of the mold cavity into the area which will be surrounded by the molded frame; closing the mold to place the opposing surfaces of the separate cores into contact with one another and into contact with the second portions of the string-securing members; injecting a plastics material into the mold around the cores and the second portions of the string-securing members; allowing the plastics material to harden in the mold cavity to form to the molded racquet frame; and removing the molded racquet frame formed of the cores, hardened plastics material and string-securing members from the mold cavity.
Claim 3
Dependent Claim
25 words
A method as claimed in claim 1, wherein said injected plastics material is a plastics material having a low setting temperature and a low viscosity.
Claim 4
Dependent Claim
16 words
A method as claimed in claim 2, wherein said injected plastics material is a methacrylate-based resin.
Claim 5
Dependent Claim
64 words
A method as claimed in claim 1, wherein each core further comprises an inflatable tube disposed inside the tube of reinforcing fibres, and wherein the method further includes the steps of inserting the inflatable tube into the tube of reinforcing fibres prior to placing the core in the mold, and maintaining the inflatable tube inflated during the injection and setting of the plastics material.
Claim 6
Dependent Claim
24 words
A method as claimed in claim 1, wherein each core further comprises a plastic foam core member disposed inside the tube of reinforcing fibres.
Claim 7
Dependent Claim
22 words
A method as claimed in claim 5, wherein said plastics foam core member is formed as an extruded polyethylene foam core member.
Claim 8
Dependent Claim
22 words
A method as claimed in claim 5, further including the step of weaving each layer of reinforcing fibres around the core member.
Claim 9
Dependent Claim
22 words
A method as claimed in claim 6, further including the step of weaving each layer of reinforcing fibres around the core member.
Claim 10
Dependent Claim
64 words
A method as claimed in claim 7, comprising successively weaving a plurality of layers of reinforcing fibres around the core member, forming on said plurality of layers a further layer of reinforcing fibres which extend parallel to each other and substantially longitudinally of the core member, and then weaving at least one outer layer of reinforcing fibres around the layer of longitudinally extending fibres.
Claim 11
Dependent Claim
19 words
A method as claimed in claim 7, wherein each layer of woven reinforcing fibres is woven as a braid.
Claim 12
Dependent Claim
21 words
A method as claimed in claim 7, wherein the reinforcing fibres are selected and woven as tows of two contrasting colors.
Claim 13
Dependent Claim
32 words
A method as claimed in claim 7, wherein the reinforcing fibres are selected from the group consisting of carbon fibres, boron fibres, glass fibres, silicon carbide fibres, aramid fibers, and combinations thereof.
Claim 14
Dependent Claim
46 words
A method as claimed in claim 1, wherein each string-securing member comprises a generally U-shaped wire loop having the upper ends of the limbs of its U-shape bent over, whereby the bent over upper ends of the loop constitute said second portion of the string-securing member.
Claim 15
Dependent Claim
24 words
A method as claimed in claim 13, wherein a plurality of said string-securing members are integrally formed by bending a single length of wire.
Claim 16
Dependent Claim
33 words
A method as claimed in claim 14, further comprising arranging further elongate reinforcing fibres to engage said upper ends of said limbs in the mold cavity, to be molded to the frame therewith.
Claim 17
Dependent Claim
13 words
A method as claimed in claim 13, wherein said wire is titanium wire.
Claim 18
Dependent Claim
14 words
A method as claimed in claim 1, wherein the plastics material is a resin.
Claim 19
Dependent Claim
14 words
A method as claimed in claim 1, wherein the plastics material is a polymer.
Claim 20
Dependent Claim
17 words
A method as claimed in claim 4, wherein the inserting step includes the inflatable tube being uninflated.
Claim 21
Dependent Claim
18 words
A method as claimed in claim 4, wherein the inserting step includes the inflatable tube being slightly inflated.
Claim 22
Dependent Claim
21 words
A method as claimed in claim 1, wherein said forming includes the string-securing members being formed as a continuous one-piece structure.
Claim 23
Dependent Claim
23 words
A method as claimed in claim 1, wherein said forming includes the string-securing members being formed as a plurality of individual stringing loops.
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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) | 1993-06-18 | 1993-12-18 | 1994-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-18 | 1997-12-18 | 1998-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-18 | 2001-12-18 | 2002-06-19 | $7700.00 | Window Closed / Lapsed |