Abstract: An aerator with variable delay of the coring head includes a lift/lower control on an aerator control panel that raises and lowers a coring head and starts or discontinues rotation of a coring head crankshaft that reciprocates a plurality of coring tines. A delay timer provides a variable time period between starting to raise or lower the coring head and the rotation of the crankshaft. A switch is provided on the control panel to preset the time period.

Abstract: An aerator with active turf calibration of a ground sensor that provides signals to a controller relating to changes in slope of a ground surface. The controller adjusts the position of a coring head based on signals from the ground sensor. The controller determines an offset from a neutral position of the ground sensor based on signals from the ground sensor on a flat surface during aeration compared to the neutral position of the ground sensor on a flat surface from static calibration.

Abstract: An aerator with active turf calibration of a ground sensor that provides signals to a controller relating to changes in slope of a ground surface. The controller adjusts the position of a coring head based on signals from the ground sensor. The controller determines an offset from a neutral position of the ground sensor based on signals from the ground sensor on a flat surface during aeration compared to the neutral position of the ground sensor on a flat surface from static calibration.

Abstract: An aerator with variable delay of the coring head includes a lift/lower control on an aerator control panel that raises and lowers a coring head and starts or discontinues rotation of a coring head crankshaft that reciprocates a plurality of coring tines. A delay timer provides a variable time period between starting to raise or lower the coring head and the rotation of the crankshaft. A switch is provided on the control panel to preset the time period.

Abstract: An aerator with coring depth adjustment includes a coring depth adjust rod centrally positioned between a left side and a right side of the coring head. A portion of the coring depth adjust rod is threaded to a frame member of the coring head, and a base of the rod abuts a stop on a frame member of the aerator. The coring depth adjust rod rotates to raise and lower the coring head relative to the aerator frame to vary the coring depth.

Abstract: An aerator hole spacing control with a hydrostatic traction drive including a pump and a plurality of wheel motors, a control arm mounted on a control shaft of the pump that controls the direction and the speed of the pump, and a cam follower on the control arm that contacts a cam surface having a minimum coring speed position, a maximum coring speed position, and a transport position. The cam surface may be linked to an operator speed control that moves the cam surface to determine where the cam follower contacts the cam surface to change the speed of the pump anywhere between the minimum coring speed position and the maximum coring speed position without stopping the pump.

Abstract: A walk behind aerator hydrostatic traction drive system includes left and right rear wheel hydrostatic motors driving left and right rear wheels positioned forwardly of a coring head, and a front wheel hydrostatic motor driving a single steerable front wheel carried in a pivotal yoke. The pivotal yoke is coupled to a handle assembly attached to a neck extending upwardly and forwardly for pivoting the single steerable front wheel about a vertical pivot axis. A check valve is connected in parallel to the front wheel hydrostatic motor. The check valve opens if the walk behind aerator moves in a forward direction and the handle assembly is turned to pivot the single steerable front wheel and the front wheel rotates more than each rear wheel, or if the walk behind aerator moves in a reverse direction.

Abstract: An aerator with coring depth adjustment includes a coring depth adjust rod centrally positioned between a left side and a right side of the coring head. A portion of the coring depth adjust rod is threaded to a frame member of the coring head, and a base of the rod abuts a stop on a frame member of the aerator. The coring depth adjust rod rotates to raise and lower the coring head relative to the aerator frame to vary the coring depth.

Abstract: An aerator hole spacing control with a hydrostatic traction drive including a pump and a plurality of wheel motors, a control arm mounted on a control shaft of the pump that controls the direction and the speed of the pump, and a cam follower on the control arm that contacts a cam surface having a minimum coring speed position, a maximum coring speed position, and a transport position. The cam surface may be linked to an operator speed control that moves the cam surface to determine where the cam follower contacts the cam surface to change the speed of the pump anywhere between the minimum coring speed position and the maximum coring speed position without stopping the pump.