Disclosed is a lawnmower with an automatic clutch, comprising a casing (10), a cutter for cutting grass (11), an electric motor for cutting grass (12), a self-propelled motor (13), a deceleration mechanism (14), a self-propelled driving shaft (15) driven by the deceleration mechanism (14), a pair of rear wheels driven by the self-propelled driving shaft (15), front wheels (17), an operating handle bar (18), a power supply (30), and a control mechanism (19) provided on the handle bar. Between the self-propelled motor (13) and the deceleration mechanism (14) an automatic clutch (20) is provided, comprising a cylinder-shaped housing (21), an output shaft (22) fixed on one side of the housing (21), a pair of symmetrical clutch blocks (23) accommodated within the housing (21), a pair of elastic pieces (24) pulling the two clutch blocks (23) towards to each other, an input shaft (26) passing between the two clutch blocks (23) and fixed onto the housing (21) to the other side opposite the output shaft (22) via a bearing (25), and a shoe (27) fixed onto the input shaft (26). Each clutch block (23) has a circular arc outer flange (231) and a central transverse sliding groove (232). The shoe (27) is slidably accommodated within the transverse sliding groove (232) of the two clutch blocks (23), and the power from the self-propelled motor (13) is transferred to the input shaft (26) via a power transmission device (131).La présente invention concerne une tondeuse à gazon à embrayage automatique comprenant un carter (10), une lame de coupe pour couper lherbe (11), un moteur électrique pour couper lherbe (12), un moteur autopropulsé (13), un mécanisme de décélération (14), un arbre de transmission automoteur (15) actionné par le mécanisme de décélération (14), une paire de roues arrières entraînées par larbre de transmission automoteur (15), des roues avant (17), un guidon de manœuvre (18), une alimentation électrique (30) et un mécanisme de commande (19) prévu sur le guidon. Entr
