A mowing sickle drive system comprises a knife bar supported by a frame and drive apparatus operable to drive the knife bar in a reciprocating linear motion at a variable drive frequency. A spring is coupled to the knife bar for applying a restoring force to the knife bar toward a neutral position when in motion. The spring has a variable modulus of elasticity that is controlled dependent upon the drive frequency.

A mowing sickle drive system comprises a knife bar supported by a frame and drive apparatus operable to drive the knife bar in a reciprocating linear motion at a variable drive frequency. A spring is coupled to the knife bar for applying a restoring force to the knife bar toward a neutral position when in motion. The spring has a variable modulus of elasticity that is controlled dependent upon the drive frequency.

A lawnmower can include a deck, blade, electric motor, battery pack, housing and fan. An air inlet can be located at the front end of the housing and adjacent to the top surface of the deck. The fan can be mounted in the housing and the housing can be configured such that, when the fan operates, air enters the housing air inlet at the front end of the housing, air flowing through the housing air inlet enters the first chamber, air flowing in the first chamber flows through the battery pack, air exiting the first chamber enters the second chamber and flows through the second chamber, air flowing in the second chamber flows through the motor in a direction that extends along the blade axis, and air exiting the motor exits the housing through the at least one air outlet.

Apparatus and methods for revitalizing artificial turf fields are disclosed. In one exemplary apparatus, the apparatus may comprise a support frame, a plurality of shearing machines installed on the support frame, and a plurality of wheels installed on the support frame. The support frame may be configured to position the shearing machines parallel to each other to tilt the shearing machines with respect a surface of the artificial turf field, and to position the shearing machines above a surface of the field at a distance such that the shearing machines cut fibers to produce trimmed fibers that have a length that can extend above infill or topmost layer of the artificial turf field. Methods for revitalizing artificial turf fields using the same are also disclosed.

Apparatus and methods for revitalizing artificial turf fields are disclosed. In one exemplary apparatus, the apparatus may comprise a support frame, a plurality of shearing machines installed on the support frame, and a plurality of wheels installed on the support frame. The support frame may be configured to position the shearing machines parallel to each other to tilt the shearing machines with respect a surface of the artificial turf field, and to position the shearing machines above a surface of the field at a distance such that the shearing machines cut fibers to produce trimmed fibers that have a length that can extend above infill or topmost layer of the artificial turf field. Methods for revitalizing artificial turf fields using the same are also disclosed.

An apparatus for revitalizing artificial turf fields may comprise a support frame, a plurality of shearing machines installed on the support frame, and a plurality of wheels installed on the support frame. The support frame may be configured to position the shearing machines parallel to each other, to tilt the shearing machines with respect a surface of the artificial turf field, and to position the shearing machines above a surface of the field at a distance such that the shearing machines cut fibers to produce trimmed fibers that have a length that can extend above infill or topmost layer of the artificial turf field. Methods for revitalizing artificial turf fields involves the aforementioned apparatus.

An apparatus for revitalizing artificial turf fields may comprise a support frame, a plurality of shearing machines installed on the support frame, and a plurality of wheels installed on the support frame. The support frame may be configured to position the shearing machines parallel to each other, to tilt the shearing machines with respect a surface of the artificial turf field, and to position the shearing machines above a surface of the field at a distance such that the shearing machines cut fibers to produce trimmed fibers that have a length that can extend above infill or topmost layer of the artificial turf field. Methods for revitalizing artificial turf fields involves the aforementioned apparatus.

A mowing sickle drive system comprises a knife bar supported by a frame and drive apparatus operable to drive the knife bar in a reciprocating linear motion at a variable drive frequency. A spring is coupled to the knife bar for applying a restoring force to the knife bar toward a neutral position when in motion. The spring has a variable modulus of elasticity that is controlled dependent upon the drive frequency.

A mowing sickle drive system comprises a knife bar supported by a frame and drive apparatus operable to drive the knife bar in a reciprocating linear motion at a variable drive frequency. A spring is coupled to the knife bar for applying a restoring force to the knife bar toward a neutral position when in motion. The spring has a variable modulus of elasticity that is controlled dependent upon the drive frequency.

A mower implement includes a cutter bar extending along a central bar axis. A rotating blade assembly is mounted on the cutter bar. The rotating blade assembly includes a disc rotatable about a disc rotation axis relative to the cutter bar, and at least one blade pivotably mounted to the disc. A blade sensor is mounted on the cutter bar. The blade sensor has a sensing field, and is positioned to detect movement of the at least one blade of the rotating blade assembly through the sensing field during each rotation of the disc about the disc rotation axis. A diagnostic controller receives the data signal from the blade sensor and is configured to analysis the blade signal and identify a fault in the rotating blade assembly. The diagnostic controller may then notify an operator of the identified fault.