A head 1 for a brush cutter of the type comprising a support element 3, connectable to a drive shaft of a brush cutter so as to be set in rotation about a vertical rotation axis Y-Y, a plurality of pins 9, connected to the support element 3, couplable to a plurality of cutting elements 2, so that every cutting element 2 is free to rotate about the respective pin 9 defining a cutting generatrix S. Said plurality of cutting elements 2 being arranged in such a way as to provide the respective cutting generatrices S tangent, in the part distal to the vertical rotation axis Y-Y, to an overall cutting diameter B, defining the overall cutting surface of the head, and tangent, in the part proximal to the vertical rotation axis Y-Y, to a fictitious circumference A, defining a central portion of the support element 3 not reached by the plurality of cutting elements 2. The A/B ratio being comprised between 0.06 and 0.3.

A head 1 for a brush cutter of the type comprising a support element 3, connectable to a drive shaft of a brush cutter so as to be set in rotation about a vertical rotation axis Y-Y, a plurality of pins 9, connected to the support element 3, couplable to a plurality of cutting elements 2, so that every cutting element 2 is free to rotate about the respective pin 9 defining a cutting generatrix S. Said plurality of cutting elements 2 being arranged in such a way as to provide the respective cutting generatrices S tangent, in the part distal to the vertical rotation axis Y-Y, to an overall cutting diameter B, defining the overall cutting surface of the head, and tangent, in the part proximal to the vertical rotation axis Y-Y, to a fictitious circumference A, defining a central portion of the support element 3 not reached by the plurality of cutting elements 2. The A/B ratio being comprised between 0.06 and 0.3.

A cutting element is configured such that it may be used to cut grass stalks or other organic stalk materials in a vegetation area. The cutting element has a main body formed from a main body material and cutting bodies formed on opposite sides of the main body which have a longer service life in the region of the cutting body relative to the prior art. At least one of the cutting bodies is formed by a cutting body material which is distinct from the main body material, is sintered and is harder than the main body material. The sintered cutting body material is formed by a hard metal or cermet and the higher hardness thereof is based on hard material particles present therein.

A cutting element is configured such that it may be used to cut grass stalks or other organic stalk materials in a vegetation area. The cutting element has a main body formed from a main body material and cutting bodies formed on opposite sides of the main body which have a longer service life in the region of the cutting body relative to the prior art. At least one of the cutting bodies is formed by a cutting body material which is distinct from the main body material, is sintered and is harder than the main body material. The sintered cutting body material is formed by a hard metal or cermet and the higher hardness thereof is based on hard material particles present therein.

A configuration of a direct drive lawnmower spindle assembly to protect sensitive electric motor components is provided. A spindle shaft of the spindle assembly is supported by upper and lower bearings. An upper end of the spindle shaft is mounted to a rotor of the electric motor and a lower end of the spindle shaft extends through the clearance opening. The lower bearing is supported by a lower bearing carrier that is mounted to the bottom of the spindle housing. The lower bearing can be serviced by removing the lower bearing carrier. A clearance gap between the spindle shaft and the clearance opening is sufficiently small to limit spindle shaft tipping to a degree that will not damage the motor. The invention also provides a friction coupling system for coupling a blade with the rotating spindle shaft.

A lawnmower cutter assembly (22) comprises a knife carrier arrangement (26) and a skid plate arrangement (30), which are axially held between an axial stop shoulder (60) of the cutter drive shaft (34) and an end piece (54) rigidly connected to the cutter drive shaft (34), the end piece (54) thereby vertically carrying the skid plate arrangement (30) and the knife carrier arrangement (26). The cutter assembly (22) may be attached to a lawnmower, which may be a robotic lawnmower, by positioning the knife carrier arrangement (26) and the skid plate arrangement (30) on the cutter drive shaft (34); and thereafter, axially locking the axial position of the knife carrier arrangement (26) and the skid plate arrangement (30) in relation to the cutter drive shaft (34).

A grass mowing machine includes a vehicle body frame, a mower deck incorporating a rotary cutter blade, a coupling mechanism for coupling the mower deck to the vehicle body frame with allowing a lateral displacement of the mower deck in a vehicle body transverse direction, a mower electric motor attached to the mower deck and configured to feed rotary power to the rotary cutter blade and a displacement operation mechanism MV for laterally displacing the mower deck in the vehicle body transverse direction in operative association with the coupling mechanism.

A cutting blade for vegetation is provided for example for use in a straw chopper or rotary mower. The blade includes a first base material and a plurality of hard surface beads of at least two different materials formed on at least one surface of the base material extending up to a cutting edge of the base material wherein the plurality of hard surface beads lie alternately side by side with touching side edges and one contains at least one different material of a different hardness relative to the other so that differential wear rates are created, and a wear profile is controlled. The softer material is burnt away at the edge by the cladding laser to form pockets so that the blade is serrated by the pockets when supplied with additional wear increasing the pockets to maintain the serrations.

A cutting blade for vegetation is provided for example for use in a straw chopper or rotary mower. The blade includes a first base material and a plurality of hard surface beads of at least two different materials formed on at least one surface of the base material extending up to a cutting edge of the base material wherein the plurality of hard surface beads lie alternately side by side with touching side edges and one contains at least one different material of a different hardness relative to the other so that differential wear rates are created, and a wear profile is controlled. The softer material is burnt away at the edge by the cladding laser to form pockets so that the blade is serrated by the pockets when supplied with additional wear increasing the pockets to maintain the serrations.

A cutter blade for a mower is disposed inside a housing of the mower and rotatably driven about a vertical axis. The cutter blade includes a blade body a blade portion provided at least at a part of a rotational direction-wise front end portion of the blade body, and a wind generating portion provided at least at a part of a rotational direction-wise rear end portion of the blade body, the wind generating portion extending more upwards than the blade portion. A thickness of the wind generating portion at the rotational direction-wise rear end portion is smaller at least partially than a thickness of the remaining part of the wind generating portion.