Turf aerator

A turf aerator comprising a ground-mobile support having a horizontal upper surface, ground aerating mechanism pivotally mounted on said support for pivotal movement downwardly to a ground-penetrating operative position and for pivotal movement upwardly to a ground-clearance inoperative position, two aerator tines movably mounted on said aerating mechanism for penetrating the turf, a crank mechanism mounted on said support and connected to said tines for vertically simultaneously reciprocating said tines in opposite vertical directions, pivot post means mounted on said horizontal surface of said support and extending above said surface and having a vertical axis, a rocker arm mounted on said pivot post means for rocking motion from a centered position about said vertical axis and relative to said pivot post means, a link connected between each respective one of said tines and a respective one of the ends of said rocker arm to thereby produce a walking action in response to movement of said support over the ground and alternate penetration of the turf by said tines whereby each said end of said rocker arm alternately moves with one of said tines forward and rearward during the walking action when said aerating mechanism is in the operative position, coiled torsion spring means coincident with said pivot post means with said spring means having opposite ends respectively yieldingly urging against said ends of said rocker arm for yieldingly urging said rocker arm to the centered position, and including a stop on said surface in the respective path of movement of each of said spring ends for restraining said spring ends from moving beyond said stops to thereby apply torque to said spring means in response to the aforesaid movement of said ends of said rocker arm and to thereby center said rocker arm and said tines when said aerating mechanism is in the inoperative position.