| 摘要 |
PURPOSE:To quicken return to a rotation angle range in design when the rotation angle of a roller support member exceeds the limit value of an rotation angle in design. CONSTITUTION:A cam 136, having a slope so as to rotate together with an extended shaft part 83c, is provided on the extended shaft part 83c of a one-side roller support member 83. One end 142a of a link 142 is in contacted with the slope of the cam 136, and the rotation of the cam 136 causes the oscillation of the link 142. The slope of the cam 136 is made a slope 140 in a rotation angle range in design, and is made slopes 139 and 141, steeper than the slope 140, in other than the upper and lower ends of the slope 140, outside the rotation angle range in design. The other end of the link 142 is in contact with a spool 158 of a speed change control valve 150, and the spool 158 can be pressed by oscillation. |
