PE Under Blocking Sweep
The PE ext stops up by the operating handle, the main axle, the position ing device, the coupling, the combination calipers and so on is composed. The main axle is composed of the inside and outside control stick, the combination calipers install separately on the inner spindle and the outer spindle, but the relative rotation, may cause the combination calipers through the operation localization handle to be in “under stops up”, “the localization”, “the vacancy” three files positions, uses in fitting’s under stopping up separately raises stops up, the jamming to adjust the localization and the jamming and the main axle is separated from and so on functinos.