| 摘要 |
PURPOSE:To reduce a noise level remarkably by applying a specific angle to a boundary edge between a driving cable and a cable guide in contact therewith and to the boundary edge of a spiral body. CONSTITUTION:The boundary edges 38 to 41 of cable guides 30 and 30' in contact with driving cables 20 and 21 form an angle alpha with the vertical axes 42 and 43 of the driving cables 20 and 21, different from 90 deg. and an acute approach angle beta enclosed with an area faced to the boundary edges 38 to 41 of the cable guide 30 and a spiral body 44 is made larger than an acute angle gamma formed with the vertical planes perpendicular to the winding of the spiral body and the vertical axis of the driving cable. According to the aforesaid construction, the spiral body is uniformly introduced into the cable guides 30 and 30' without causing a shock and a noise level can be remarkably reduced. |
