Fastening means for fitting an accessory, especially an ear muff, to a safety helmet
OwnerBo G. Lonnstedtinventor
Life of this patent
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Abstract
A fastening means for fitting an ear muff to a safety helmet has an arm which is mounted in a housing intended for attaching to the helmet. A pivoting end portion of the arm situated in the housing is acted on by a disc-type spring means arranged in the housing. The line of action of the spring force has a decreasing leverage to the pivoting location of the arm for increasing arm swing-out, the pivoting moment exercised by the spring means on the arm being substantially constant within a swing-out range normal for the arm when it is in use. This results in a contact force for the ear muff which is essentially independent of the amount of swing-out.
Claims9
A fastening means for fitting an accessory, e.g. an ear muff, on a safety helmet or the like, where an arm, intended for an accessory, is supported at a pivoting end portion in a housing intended for attaching to the helmet, the arm thus forming a two-armed lever, the pivoting end portion of which, situated in the housing, being acted on by a spring means having a convex side, said spring means arranged in the housing, to urge the opposite, free end of the arm, situated outside the housing, in a direction towards the head of the wearer, characterized in that the pivoting end portion of the arm has a contact portion for bearing against the central portion of the convex side of the spring means, which is of the disc type and which is retained at its periphery to the side of the housing intended to face towards the outside of the helmet, the force of the spring means having a line of action essentially perpendicular to the intended plane of contact between the helmet and the housing.
Dependencies are inferred from the claim text.