| 摘要 |
984,020. Rotary-scythe mowers. HAYTERS Ltd. Dec. 4, 1963 [Dec. 24, 1962], No. 48564/62. Heading A1F. [Also in Division F2] A four-wheeled motor-driven steerable rotary-scythe grass cutter comprises rear wheels 10, 11 respectively rotatable on and fast with an axle 17, clutch linings 15, 16 on a motor-driven sprocket 14 rotatable and axially slidable on the axle, clutch driven plates 21, 28 respectively fast with the wheel 10 and axially slidably keyed on the axle, and a manually controlled lever 30 movable into three positions, viz. rightward, in which the plate 28 is axially urged, through a needle thrust bearing 29, to fully engage the sprocket 14 which in turn is axially urged to fully engage with the plate 21, thereby providing a firm drive to both wheels; leftward, in which the plates are disengaged from the sprocket; and intermediate, in which a slipping drive is provided to enable the cutter to be steered during drive. A hand lever 43 in a gate 47 acts on the lever 30 through a rod 38 and a nut 46. A strong spring 45 and a weaker spring 42 are interposed respectively between a frame member 32 and the lever 30 and between a frame member 41 and the rod 38. With the hand lever in one end notch of the gate the nut 46 clears the lever 30 to allow the spring 45 to urge rightwardly the lever 30; with the hand lever in the opposite end notch of the gate the lever 30 is leftwardly urged against the spring 45; and with the hand lever freely floating, the sprocket 14 is gripped lightly between the plates 21, 28 by a force equal to the difference of the forces exerted by the two springs. The front wheels are freely mounted and preferably means is provided adjustable to raise the front end of the frame, together with the cutter, with respect to the wheels. A multi-bladed cutter plate may be mounted for rotation in a horizontal plane. A single motor drives both the cutter and the rear wheels. |
