Manually rotatable control or selector knob member

Claim 1

A rotatable control assembly comprising: an operating shaft, a manually rotatable control member having a locking hole of a preselected larger diameter than the diameter of said shaft, said locking hole adapted to receive an outer end portion of said operating shaft, the outer end portion of said operating shaft being longitudinally slotted so that the portions thereof on opposite sides of the slot are inwardly flexible to be resiliently frictionally fittable into said locking hole, the surfaces of at least one of said flexible portions of said operating shaft on opposite sides of said slot therein being fluted longitudinally, and said locking hole of said manually rotatable control member being lined with a flexible elastic material into which said inwardly flexible fluted portions of said operating shaft are closely frictionally fitted, to provide a friction locking engagement between the outer end portion of said operating shaft and said manually rotatble control member, whereby said control member is selectively locked onto said operating shaft at a desired angular position.