Connecting rod assembly with reduced length variability

摘要

A connecting rod assembly for rocking piston compressors, diaphragm compressors and vacuum pumps is provided where the overall height of the connecting rod assembly is dependent only upon the overall height of the connecting rod structure and is not dependent upon the thickness of the diaphragm or the thickness of the retainer plate. The connecting rod includes a disk portion for supporting an annular diaphragm in the case of a diaphragm pump or a cup in the case of a rocking piston compressor or a vacuum pump. The connecting rod also includes a distal end section that extends upward through the annular diaphragm and through an annular retainer plate. The diaphragm or cup is sandwiched between the annular retainer plate and the disk portion of the connecting rod. The overall height of the assembly is determined by the distance between the end face of the disk portion of the connecting rod and the crank end of the connecting rod. The annular retainer plate bottoms out on the disk portion of the connecting rod and therefore does not contribute any height variability to the assembly. Because the diaphragm or cup is trapped below the annular retainer plate, the diaphragm does not contribute any height variability to the assembly as well.