Protective helmet

Abstract

An improved protective helmet is made of a dual density, closed-cell, polymeric foam laminate. The inner layer is a lower density (3.8 to 5 pcf), closed-cell, polymeric foam for comfort, absorbing minor impacts and distributing impact stress over a larger surface of the skull to reduce injury. The outer layer is a higher density (5 to 7.2 pcf), closed-cell, polymeric foam to absorb major impacts and add structural stability to the helmet. Ventilation holes provide airflow through the helmet. Cushioning pads may be added inside the helmet for customizing fit and improving ventilation. The preferred material for the inner and outer layers of the laminated, dual density protective helmet is a nitrogen blown, cross-linked, closed-cell, polyethylene foam. The dual density, closed-cell, polymeric foam laminate of the helmet provides improved impact attenuation. The laminate also reduces the weight of the helmet, which improves comfort and reduces neck fatigue for the wearer. The polyethylene foam laminate also exhibits improved recovery after an impact. In a second impact at the same location, the helmet has approximately 70 percent of the original impact attenuation value and after repeated impacts it has approximately 50 percent of the original impact attenuation value. The helmet also provides superior resistance to environmental factors, including moisture, heat and damage from rough handling. The manufacturing method is a low pressure compression molding process which simultaneously shapes the protective helmet and laminates the inner and outer layers of the helmet shell.

Dependencies are inferred from the claim text.