(under subclass 170) Spring device, further including a second end thrust member at the other end of the spring element; and in which the spring element is adapted either (a) to maintain said end thrust members a predetermined distance apart or (b) selectively to maintain one of the members, or the contact point between said one member and the end of the element, at each of a pair or predetermined positions on opposite sides of the helix axis.
SEE OR SEARCH THIS CLASS, SUBCLASS:
159, for an over-center snap spring of leaf or disc construction.
