GB321719A - Improvements in and relating to lawn mowers - Google Patents

Abstract

321,719. Garrard, C. G. Aug. 18, 1928. No Patent granted (Sealing fee not paid). Lawn-mowers. -A motor lawn-mower comprises a rotary member carrying the blades and having combined with it, so as to rotate therewith, the cylinder system, crank chamber, and silencer of the engine. The machine shown comprises side frames 7, handles 6, an adjustable front roller 8, a rear roller 11, and a magneto 9. The two latter are driven by a chain 19, with or without a clutch and speed gear. The handles may carry a fuel tank or may be made hollow to contain the fuel. The rotary member 16 carrying the blades 20 is mounted on hollow sleeves 13, 15 fixed in the side frames 7. It consists of a casting having bolted to it an end member carrying a sprocket 18 for driving the chain 19. The casting has cooling ribs 22 and includes a cvlinder 21 for a two-stroke engine provided with an inlet passage 23 and exhaust ports 24 leading to a silencer 25. The cylinder 21 and inlet passage 23: open into a closed crank chamber 26 into which air and petrol are drawn through a valve 28, the supply of petrol being controlled by a needle valve 31. An inclined pin 34 is mounted to rotate in an extension of the holder sleeve 15 and carries at right angles to it a pin 35 on which is a, sleeve 36 pivotally connected to the rod 37 of the piston 38. The pin 35 extends into a guide block or roller 39 working in a guideway 40 in the casting 16. Air ducts 41 open into a central passageway 42 communicating with the interior of the sleeve 13. A sparking plug 43 projects into this passageway the connection 44 to the magneto permitting rotary motion. The engine may have two or more cylinders, and may have a four-stroke cycle.