Abstract: Described herein is a work tool (100) comprising: a motor (125) provided with a drive shaft (130), a casing (195) containing the motor (125) and provided with at least one inlet opening (235) and with at least one outlet opening (240), an implement (135) positioned outside the casing (195) and kinematically connected with the drive shaft (130), and a fan (245) kinematically connected to the drive shaft (130) and able to generate a flow of air from the inlet opening (235) towards the outlet opening (240) of the casing (195) passing in heat exchange relationship with the motor (125), wherein said fan (245) is contained inside the casing (195) in a space located between the motor (125) and the implement (135).

Abstract: Described herein is a work tool (100) comprising: a motor (125) provided with a drive shaft (130), a casing (195) containing the motor (125) and provided with at least one inlet opening (235) and with at least one outlet opening (240), an implement (135) positioned outside the casing (195) and kinematically connected with the drive shaft (130), and a fan (245) kinematically connected to the drive shaft (130) and able to generate a flow of air from the inlet opening (235) towards the outlet opening (240) of the casing (195) passing in heat exchange relationship with the motor (125), wherein said fan (245) is contained inside the casing (195) in a space located between the motor (125) and the implement (135).

Abstract: A two-stroke internal combustion engine includes: a piston-cylinder group defining a combustion and a pumping chamber, the piston mobile in the cylinder between a bottom dead center where the combustion chamber's volume is maximum and the pumping chamber's volume is minimum, and a top dead center, where the combustion chamber's volume is minimum and the pumping chamber's volume is maximum. The engine also includes an intake conduit communicating with the pumping chamber, an exhaust conduit communicating with the combustion chamber, at least a pair of transfer conduits allowing communication between the pumping and combustion chambers, and at least two primary channels in the piston, individually provided with an inlet facing onto the exhaust conduit and an outlet facing on a respective transfer conduit at least when the piston is at the top dead center. A lateral surface of the piston includes a lowering where the primary channels inlets are located.

Abstract: Herein described is a two-stroke internal combustion engine (100), comprising: a cylinder (135) having a pre-set central axis (B); a piston (145) slidably coupled to the cylinder (135) and suitable to divide the interior volume thereof into two distinct chambers, including a combustion chamber (150) and a pumping chamber (155); an intake duct (160) communicating with the pumping chamber (155); an exhaust duct (170) communicating with the combustion chamber (150); and at least one scavenging duct (180) suitable to place the pumping chamber (155) in communication with the combustion chamber (150); wherein said scavenging duct (180) comprises a terminal portion (190) leading to the combustion chamber (150) which extends with configuration diverging from an inlet section (200) up to an outlet section (205) obtained on a lateral surface of the cylinder (135).

Abstract: A method for controlling the operation of a spark ignition internal combustion engine is described. The engine includes: a combustion chamber, an intake duct for placing the combustion chamber in communication with the external, a throttle valve arranged inside the intake duct, a carburetor for introducing fuel into the intake duct to form an air/fuel mixture to be intaken into the combustion chamber, and a spark plug arranged inside the combustion chamber to generate a spark for igniting the combustion of the air/fuel mixture. The method includes: monitoring the opening degree of the throttle valve; monitoring the speed of the engine, preventing the spark plug from generating the spark, if the opening degree of the throttle valve drops below a first opening degree threshold value and the speed of the engine is greater than a first engine speed threshold value.

Abstract: A two-stroke internal combustion engine includes: a piston-cylinder group defining a combustion and a pumping chamber, the piston mobile in the cylinder between a bottom dead center where the combustion chamber's volume is maximum and the pumping chamber's volume is minimum, and a top dead center, where the combustion chamber's volume is minimum and the pumping chamber's volume is maximum. The engine also includes an intake conduit communicating with the pumping chamber, an exhaust conduit communicating with the combustion chamber, at least a pair of transfer conduits allowing communication between the pumping and combustion chambers, and at least two primary channels in the piston, individually provided with an inlet facing onto the exhaust conduit and an outlet facing on a respective transfer conduit at least when the piston is at the top dead center. A lateral surface of the piston includes a lowering where the primary channels inlets are located.

Abstract: A method for controlling the operation of a spark ignition internal combustion engine is described. The engine includes: a combustion chamber, an intake duct for placing the combustion chamber in communication with the external, a throttle valve arranged inside the intake duct, a carburetor for introducing fuel into the intake duct to form an air/fuel mixture to be intaken into the combustion chamber, and a spark plug arranged inside the combustion chamber to generate a spark for igniting the combustion of the air/fuel mixture. The method includes: monitoring the opening degree of the throttle valve; monitoring the speed of the engine, preventing the spark plug from generating the spark, if the opening degree of the throttle valve drops below a first opening degree threshold value and the speed of the engine is greater than a first engine speed threshold value.

Abstract: Herein described is a two-stroke internal combustion engine (100), comprising: a cylinder (135) having a pre-set central axis (B); a piston (145) slidably coupled to the cylinder (135) and suitable to divide the interior volume thereof into two distinct chambers, including a combustion chamber (150) and a pumping chamber (155); an intake duct (160) communicating with the pumping chamber (155); an exhaust duct (170) communicating with the combustion chamber (150); and at least one scavenging duct (180) suitable to place the pumping chamber (155) in communication with the combustion chamber (150); wherein said scavenging duct (180) comprises a terminal portion (190) leading to the combustion chamber (150) which extends with configuration diverging from an inlet section (200) up to an outlet section (205) obtained on a lateral surface of the cylinder (135).