Ski apparatus
US4272578A · kind A · utility
Inventor
Key dates
| Filing date | May 31, 1979 |
| Grant date | Jun 9, 1981 |
| Priority date | — |
| Expiry date | May 31, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24942
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Ski structure having good vibratory characteristics formed of a composite material including a core of light material for which the maximum allowable shear stress in the longitudinal direction and the maximum allowable vertical compression stress are, respectively, greater than 25 bars and 21 bars, the core being disposed between upper and lower working layers. The upper layer is constituted by a material whose modulus of elasticity in the longitudinal direction is less than 4,700 hbars. The material of the lower layer has a modulus of elasticity greater than 4,700 hbars. The product of the cross-sectional area and modulus of elasticity is between about 140,000 and 400,000 hbars mm.sup.2 for the upper layer, and between about 130,000 and 500,000 hbars mm.sup.2 for the lower layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.