Cam wheel assembly for refrigerant recovery machine

A cam wheel assembly comprising:

• a frame member comprising at least two symmetrical frame parts and a plurality of rails, each said frame part comprising a base and at least two arms respectively extending from two distal ends of said base, the arms of one said frame part being respectively connected to the arms of the other said frame part, the base of each said frame part comprising a plurality of locating grooves located on an inner side thereof and arranged in a parallel manner, each locating groove longitudinally extending along the base between the at least two arms, said rails being respectively mounted in the locating grooves of said frame parts and peripherally protruding over an outer surface of the associated frame part;
• a sliding block mounted inside said frame member, said sliding block comprising a plurality of sliding grooves extending around the periphery thereof and kept in contact with the rails of said frame member, an axial through hole extending through two opposite ends thereof, and an axle bearing accommodated in said axial through hole;
• and
• a cam wheel set comprising a first cam wheel and a second cam wheel arranged on two opposite sides relative to said sliding block, said first cam wheel comprising a coupling rod eccentrically extending from one side thereof adjacent to said sliding block and inserted into said axle bearing and a pivot rod perpendicularly centrally extending from an opposite side thereof, said second cam wheel comprising a coupling tube eccentrically extending from one side thereof adjacent to said sliding block and directly engaged with the coupling rod of said first cam wheel in said axle bearing and a connection rod perpendicularly centrally extending from an opposite side thereof.