Overload prevention handle

Claim 1

In a handle for preventing overloading of a handle operated mechanism by undergoing a change in shape upon application of a predetermined mechanism operating force thereto, wherein the handle includes an elongated main body portion having one end thereof adapted for operable connection to said mechanism for rotation about a first axis extending transversely of said body portion, an extension portion to which mechanism operating forces are to be applied, pivot shaft means for mounting said extension portion on another end of said body portion for relative pivotal movement about a second axis arranged essentially parallel to said first axis, and constraining means for normally maintaining said extension portion in a normal mechanism operating position in substantial alignment with said body portion while releasing said extension portion for pivotal movement about said second axis away from said normal position into an overload position upon application of said predetermined operating force thereto, said constraining means tending to return said extension portion to said normal position from saiD overload position upon removal of said predetermined operating force therefrom, said constraining means including a stack of spring discs and means for mounting said discs on said body portion, said mounting means including first and second members fixedly and movably mounted on said body portion, respectively, said second member having an end arranged for cooperative engagement by said extension portion, whereby said stack is compressed between said members to permit movement of said extension portion from said normal position when said predetermined operating force is applied to said extension portion; the improvement wherein said extension portion is formed with a concave recess opening towards said end of said second member, said recess being of partial cylindrically shaped configuration and having its axis disposed essentially parallel to said second axis, said end of said second member is an essentially planar surface and disposed transversely of the direction of movement of said second member relative to said body portion, and there is further provided a friction member formed with a partial cylindrically shaped bearing surface dimensioned to be partially received in surface to surface rotary frictional engagement within said recess and lengthwise extending planar bearing surface arranged in sliding face to face frictional engagement with said planar surface of said second member, whereby pivotal movement of said extension about said second axis results in simultaneous rotations of said friction member within said recess and sliding movements of said friction member across said planar surface of said second member.