Head clamping mechanism of opening power pincers

Abstract

The invention relates to head clamping mechanism of opening power pincers, which is mainly composed of opening gear, opening gear cover, butterfly jaw plate, outside tooth plate, core shaft, planet gear, guide wheel, brake drum and rotation axis. The opening gear is fixed to the opening gear cover by bolt. Each butterfly jaw plate is fixed to the core shaft. The two ends shaft journal of respective core shaft are respectively installed in the shaft bore of the opening gear and opening gear cover. The planet gear is installed at the outer end of the upper shaft journal of respective core shaft. It transmits brake moment by the guide wheel and the brake gear engagement on the brake drum to make respective butterfly jaw plate rotate to the outside tooth plate for contacting pipe to clamp tightly. The invention can continuously clamp optional pipe without changing any part in positive and negative direction.

Description

technical field [0001] The invention relates to a power tong for loading and unloading pipe threads, in particular to a clamping mechanism for a main tong head of an open-type power tong. Background technique [0002] There are two basic types of the clamping mechanism of the main tong head of the open-type power tongs, one is the inner surface roller climbing type clamping mechanism, the main structure is: in the cavity contained in the open gear and the open gear cover There are four inner curved slopes, the rollers are installed on the jaws, and the jaws are installed in the square holes of the jaw frame, when the open gear temporarily rotates relative to the jaw frame, the rollers roll and climb along the inner curved surface of the slope, The radial translation of the jaw plate is formed, so that the tooth plate on the jaw plate contacts the pipe, and the thread operation of loading and unloading the pipe is realized. The other is the outer curved surface roller climbi...

AI Technical Summary

Problems solved by technology

This mechanism still has the following deficiencies: First, the upper and lower inner teeth of the open gear mesh with the planetary gears, especially the lower inner teeth. Once iron filings or other hard debris enter the meshing pair, the meshing pair will be stuck To remove debris, the pliers head must be disassembled; second, the opening gear must rotate at a certain angle relative to the upper and lower connecting plates of the planet carrier, and when oil, mud, sand and other mechanical impurities enter the relative rotation gap, the The relative rotation is hindered, and the clamping action fails; the third is that the planetary gear bears the torque transmission of the clamp head. In order to meet the strength requirements, it must have sufficient axial dimension, which not only makes the structure complicated, but also occupies the height space of the outer curved tooth plate. , in order to meet the height requirements of the tooth plate, the axial dimension of the tong head must be increased. This clamping mechanism will not be applicable when the distance between the clamping joint of the drilling tong, the main tong and the backup tong is strictly limited; The height of the plate will deteriorate the strength of the tooth plate and increase the damage to the surface of the pipe, which will also make the mechanism unsuitable

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