Driven tine wheel type aerator having improved tine geometry

In an aerator for use in core-type aerification of turf having an upper thatch and root zone and an underlying subsoil zone, said aerator including a chassis, means operatively associated with said chassis in a manner enabling movement along a turf surface, a tine wheel assembly carried by said chassis for rotation about an axis generally transverse to the direction of movement of the aerator during operation, and power means carried by said chassis and operatively associated with said tine wheel assembly so as to enable driven rotation thereof;

• the improvement wherein said driven tine wheel assembly includes a plurality of tubular coring tines affixed about the periphery of said wheel assembly in outwardly extending relation therefrom, each of said tines including an outer open ended tubular penetrating end having a longitudinal axis defining a predetermined forward rake angle of 41.degree., the number of said tines, their said rake angles, the diameter of said tine wheel assembly and the weight of said aerator having a predetermined relation so as to effect substantially axial penetration of said tines into the turf and substantially axial withdrawal of said tines from the same surface openings made upon penetration, said predetermined relation causing said tine wheel to undergo rotation about an instant rotational center spaced below the surface of the turf, each of said tines being operative to remove a core of thatch and subsoil with the outer periphery of the tubular penetrating end effecting compression of the thatch and root zone peripherally of the core during entry of said penetrating end into the turf and removal therefrom so as to prevent lifting of the turf adjacent said opening.

In an aerator for use in core-type aerification of turf having an upper thatch and root zone and an underlying subsoil zone, said aerator including a chassis, means operatively associated with said chassis in a manner enabling movement along a turf surface, a tine wheel assembly carried by said chassis for rotation about an axis generally transverse to the direction of movement of the aerator during operation, and power means carried by said chassis and operatively associated with said tine wheel assembly so as to enable driven rotation thereof;

• the improvement wherein said driven tine wheel assembly includes a plurality of tubular coring tines affixed about the periphery of said wheel assembly in outwardly extending relation therefrom, each of said tines including an outer open ended tubular penetrating end having a longitudinal axis defining a predetermined forward rake angle of approximately 41.degree., and a tapered cutting edge lying in an inclined plane relative to the longitudinal axis of the corresponding tine, the number of said tines, their said rake angles, the diameter of said tine wheel assembly and the weight of said aerator having a predetermined relation so as to effect substantially axial penetration of said tines into the turf and substantially axial withdrawal of said tines from the same surface openings made upon penetration, said predetermined relation causing said tine wheel to undergo rotation about an instant rotational center spaced below the surface of the turf, each of said tines being operative to remove a core of thatch and subsoil with the outer tapered periphery of the tubular penetrating end effecting compression of the thatch and root zone peripherally of the core during entry of said penetrating end into the turf and removal therefrom so as to prevent lifting of the turf adjacent said opening.