Low-noise pump assembly

摘要

The low-noise pump assembly (10) comprises a unitized assembly wherein a drive shaft (17) of the motor (16) is mated directly with an eccentric coupling (23). The eccentric coupling (23) has a through bore (21) which receives at one end the drive shaft (17) and at the other end a center post (30) of the pump housing. Disposed between the center post (30) and eccentric coupling (23) is a radially inner bearing mechanism (60), and disposed between the exterior of the eccentric coupling (23) and an opening (52) of a ring member (50) is a radially outer bearing mechanism (70). The ring member (50) engages at least one reciprocating piston assembly (45). Rotation of the drive shaft (17) causes rotation of the eccentric coupling (23) to effect reciprocating motion of the pump piston (48).