Abstract: A clothes washing machine includes a washing basket and an oscillating agitator disposed at a bottom of the washing basket. The agitator includes a plate having radial blades, and an upward guide fixed at a center of the plate. A reciprocable member is mounted on the guide for upward and downward movement relative thereto for preventing the clothes from becoming entwined. The guide includes a first screw thread which engages a second screw thread on the reciprocable member so that upward and downward forces are alternatively applied to the reciprocable member in response to relative rotation between the first and second screw threads, causing the reciprocable member to reciprocate up and down. The upward force terminates in response to a lower end of the second screw thread reaching an upper end of the first screw thread. The downward force terminates in response to an upper end of the second screw thread reaching a lower end of the first screw thread.