A tape positioning auxiliary sheave inverting means

The present invention relates to a sheave with Auxiliary positioning means reversing, the reversing sheave means includes a housing, a drive transmission mechanism and the workpiece reversing auxiliary positioning means; sheave means engaging said outer gear, which includes a mechanism four outer sheave grooves dial having a dial and two deadbolt; means a linear positioning said auxiliary cylinder push rod cam mechanism, the cam mechanism comprises a dial with the outer circumferential surface coaxial with the curve and a cylindrical cam groove reciprocable along a line direction of the cylindrical cam driven by a cylindrical cam drive member; said cylindrical cam and the dial can be driven synchronously rotate the driven member in place of the sheave assisted positioning, so that the sheave of the turning device of the present invention has high positioning accuracy, positioning reliable.