A SPRING FOR VALVE CONTROL IN ENGINES

摘要

A spring system (400) includes an axially moving center attachment (517) located between two static attachments (511, 521). Bi-directional axial center deflections cause push-pull restoration forces. There is little mechanical fixturing preload stress acting on material also subject to high cyclic stresses. The spring material includes an unbroken path between the two static attachments (511, 521), going through the center attachment (517). In one embodiment, the unbroken path is a length of wire bent into substantially parallel side-by-side helices clamped statically at the bottom of each helix. A moving attachment grips the center of the wire bridging diagonally between the tops of the helices. In a second embodiment, the unbroken path is a length of wire bent into end-to-end helices sharing a common axis and clamped statically at the axially opposite ends of the spring. A moving attachment grips the center of the wire where it bridges across the common axis in transition from a right-hand helix on one end to a left-hand helix on the opposite end of the spring.