US5943706A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helmet
Assignee: TS Tech Co Ltd
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Filing: 1997-07-25
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Granted: 1999-08-31
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Expires: 2017-07-25
Abstract
Abstract The present invention concerns a helmet including a shell formed from a thermoplastic resin, for example, by blow molding or injection molding, and a shock absorbing liner disposed on the inside of the shell. The shock absorbing liner is formed of polyvinylidene chloride foam. By forming the shock absorbing liner of polyvinylidene chloride foam, it is possible to provide a helmet having less temperature dependent change in compression strength upon molding, excellent shock adsorption and restorability, excellent impact shock adsorbing performance upon a second hit on one identical portion and excellent dimensional accuracy in manufacture.
Inventors
- 👤 Iwao Miyajima
- 👤 Hideshi Kitahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:44
CPC Classifications
A; A42; A42B; A42B3/00; A42B3/04; A42B3/10; A42B3/12; A42B3/125; G; G01; G01N; G01N3/00; G01N3/40; G01N3/48
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
33 words
A helmet having a shell formed by molding of a thermoplastic resin and a shock absorbing liner disposed on inside of the shell, in which the liner is formed of polyvinylidene chloride foam.
Claim 2
Dependent Claim
33 words
A helmet having a shell formed by molding of a thermoplastic resin and a shock absorbing liner disposed on inside of the shell, in which the liner is formed of polyvinylidene chloride foam.
Claim 3
Dependent Claim
31 words
A helmet as defined in claim 1, wherein said liner comprises a dual layered structure of a high density polyvinylidene chloride foam layer and a low density polyvinylidene chloride foam layer.
Claim 4
Dependent Claim
21 words
A helmet as defined in claim 2, wherein said high density polyvinylidene chloride foam layer is in contact with said shell.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-08-30 | 2003-03-01 | 2003-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-08-30 | 2007-03-01 | 2007-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-08-30 | 2011-03-01 | 2011-08-31 | $7700.00 | Window Closed / Lapsed |