A shaped cross is a component that connects the piston and connecting rod,and has a guiding effect.A large number of connecting rod small ends are used in compressors.

A large number of compressors use closed shaped cross sections with small ends of connecting rods placed inside the cross section,while a few compressors use open shaped cross sections that are matched with forked connecting rods.The connection types between the special cross and the piston rod are divided into threaded connection,coupling connection,flange connection,etc.The threaded connection structure is simple and easy to adjust the dead center clearance in the cylinder.However,when adjusting,it is necessary to rotate the piston,and when cutting threads on irregular four-way bodies,it is easy to wear and tear after multiple disassembly and assembly,making it difficult to meet accuracy requirements.Therefore,this structure is commonly used on small and medium-sized compressors.The structure of clamping and fixing with two nuts instead of cutting threads on the irregular four-way body can be used for large and medium-sized compressors.The coupling and flange connection structure is easy to use and adjust,making it easy to align the piston rod with the irregular cross.But the structure is complex and bulky,often used on large compressors.The connection between the irregular four-way joint and the connecting rod is completed by the irregular four-way pin.