| 摘要 |
PROBLEM TO BE SOLVED: To restrain the maximum operation force of a grip/clutch lever, and reduce a change ratio of an operation force. SOLUTION: In this working machine 10, a travel clutch is interposed between an engine 14 and a rear wheels 13, tire grip 70 is attached longitudinally swingably to handles 50L, 50R extended rearwards from a machine body 11, and motive power is transmitted from the travel clutch to the rear wheels, in response to pushing-out force for pushing the grip frontwards. The travel clutch is an oil immersion type cone clutch of which the incomplete clutching condition is changed by bearing pressure between male and female taper faces. A clutch characteristic curve is found by using (viscosity η of lubricating oil)×(rotational difference N between the male and female taper faces)/(the bearing pressure P between the male and female taper faces) as a transverse axis, and using a friction coefficient of the cone clutch corresponding to the η×N/P as an axis of ordinate, and a broken point provided when the clutch characteristic curve is approximated linearly is determined based thereon. A range of the bearing pressure between the male and female taper faces is determined to make a switching point between low load traveling and high load traveling of the pedestrian-controlled type working machine conformed with the broken point. |
