Walk-behind lawn mower

A walk-behind lawn mower comprising:

• a cutter;
• a housing covering the cutter for allowing rotation of the cutter to cut grass;
• the housing including a front wall portion covering a front part of the cutter and a portion other than the front wall portion, the front wall portion extending laterally of the housing;
• the front wall portion having a thickness more than twice a thickness of the portion other than the front wall portion;
• the front wall portion having a smooth downwardly convexly curved bottom surface;
• the front wall portion serving as a handle for being held by user's fingers when the lawn mower is to be lifted up, and
• wherein the front wall portion includes,
• an inner wall disposed on a side of the cutter,
• an outer wall spaced outward from the inner wall,
• generally vertical ribs disposed between the inner wall and the outer wall,
• the inner wall having a downwardly convexly curved bottom surface,
• the outer wall having a downwardly convexly curved bottom surface,
• the ribs each having a downwardly convexly curved bottom surface, and
• the downwardly convexly curved bottom surface of the inner wall, the downwardly convexly curved bottom surface of the outer wall and the downwardly convexly curved bottom surfaces of the ribs being flush with one another and jointly forming the smooth downwardly convexly curved bottom surface of the front wall portion.