The present invention relates to double-lens ski goggles.
Ski goggles are known consisting of a flexible rubber frame which adapts to the skier's face and supports a coloured or non-coloured lens.
If used in very cold climates, the lenses tend to mist up as a result of the skier's body or breath temperature during use, especially when the skier is resting.
To prevent the lenses from misting up, it is known to:
These anti-misting treatments present advantages and disadvantages.
The chemical treatment produces an anti-misting effect when the lens has a surface temperature of about 0° C. or higher, but is not satisfactorily effective in an environment in which the surface temperature falls to 0° or lower because the mist forms water droplets which freeze on the lens surface. Moreover, this treatment has little effect at any lens temperature, seeing the low insulating power of plastic having a thickness of just a fraction of a millimetre.
If the optical system comprises two flat lenses (or curved to follow the face profile) and an internal heat insulating space, the lenses are more effective in thermally insulating the goggles, so that the lenses mist up only in more severe circumstances, such as intense perspiration or very cold temperatures.
However these lenses have the drawback that the pressure variation within the internal space between the two lenses, due to atmospheric pressure or temperature change during a descent, deforms the lenses and distorts the visual field. For example, when a lens system is used with the internal space well sealed, a pressure difference arises between the inside and outside of the lenses which subjects the lenses to an overall compressive deformation and distorts the visual field.
To obviate this drawback it has been proposed to perforate one of the two lenses (the inner) and to apply to the hole a diaphragm which is permeable to air but not to water.
However this solution has certain drawbacks, and in particular:
All these drawbacks are eliminated according to the invention by ski goggles as described herein.
The present invention is further clarified hereinafter with reference to the accompanying drawings, in which:
As can be seen from the figures, the double-lens goggles according to the invention comprise a masking element 2, an elastic strap 4 connected to the masking element 2, and a lens system 6 removably secured to the masking element 2.
The masking element 2, which is made of soft material such as polyurethane rubber, comprises a perimetral seat for inserting the lens system.
The lens system comprises an inner lens 8 and an outer lens 10, which are of transparent plastic and can be flat or curved, with a specific internal space 12 formed between the two lenses. The internal space serves as a heat insulating layer.
The two lenses are connected together by a neoprene gasket 14 (
This type of membrane consists of a microporous filter permeable to air but not to water, such as a GORE-TEX® fabric.
In a variant, a complete gasket portion 14 is replaced by a layer of membrane 16 (
In the embodiment shown in
To enable air to pass through the membrane occupying this chamber, the gasket joining the lenses 8 and 10 can be provided with a cut 20.
Number | Date | Country | Kind |
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VE2010A000046 | Jul 2010 | IT | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP11/58541 | 5/25/2011 | WO | 00 | 1/28/2013 |