US Patent 7089724 Flexible push/pull/rotary cable

A hybrid flexible wire shaft having an inner portion with the characteristics of a push/pull shaft having at least one layer of wire groups helically wound on a core wire at a relatively high pitch angle, and an outer portion with the characteristics of a torsional transmission flexible shaft having two or more layers of wire groups wound on the central portion at a relatively low pitch angle. Each layer of the outer group is wound in a direction opposite to the wind direction of each adjacent layer of that group. In an alternate construction, the high and low pitch portions are reversed and an additional outer layer is provided which is wound in a direction opposite to the outermost layer of the high pitch portion.