Invalidity dossier
US 5315948
Luff pad for roller reefing and furling sails
Current assignee: Sail Systems Inc
Added 9/23/2026, 4:03:15 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview: US5315948A — Luff Pad for Roller Reefing and Furling Sails
Bibliographic data (per supplied source): Patent number US5315948A; application US07/772,885; inventor Hayden D. Brown; original assignee Sail Systems, Inc.; filed and priority date 1991-10-08; granted/publication date 1994-05-31; status listed as expired — fee related, with anticipated expiration 2011-10-08. Classification B63H9/067 (sails characterised by construction or manufacturing process).
Purpose: On roller furling/reefing sails, rolling the luff onto the stay reduces luff tension, and bulk in the foot and leach makes the rolled volume greatest at tack and head. The sail then sags, develops excessive draft, and its point of maximum draft moves aft, hurting windward performance. The invention addresses this by supplying a luff pad.
Plain-language scope: The pad is a deformable laminate of an elastomeric polyurethane foam core faced on at least one side—optionally both—with an adhesively bonded fabric or film, preferably sailcloth. It is bonded and/or stitched to the luff, tapered from mid-luff toward tack and head, with a luff tape preferably bonded and stitched over each laminate face. Typical dimensions: about 0.1–2.5 cm thick, about 10–90 cm wide, in running lengths cut roughly to luff length; a general-purpose product is about 3–5 mm thick and 20–40 cm wide. The core may be generally any elastomeric polyurethane foam, firm enough to resist compression when rolled; facings may be films such as PVC or polyethylene terephthalate, or fabrics, with polyester sailcloth (e.g., 2.5 oz square-weave Dacron®) preferred. The fabric is preferably uncoated, unsized, and scoured to improve adhesive wetting and bonding.
Not established by this excerpt: The claims (only their presence in the document is indicated); the complete description and omitted text (including the full adhesive discussion); the drawing contents of FIGS. 1–3 beyond their captions; and any embodiment details, examples, or measurements not quoted above. No litigation, ownership-transfer, validity, or prior-art conclusions are drawn, per instructions.
Source: https://patents.google.com/patent/[US5315948](/patent/US5315948)/en
Generated 10/1/2026, 9:51:11 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Derivative works
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