US Patent 11867165 Drive system for a positive displacement pump

A drive system for a pump includes a housing, first and second fluid displacement members, and a reciprocating member configured to mechanically displace the first and second fluid displacement members through respective suction strokes. The housing and fluid displacement members define an internal pressure chamber configured to be filled with a working fluid having a charge pressure. The internal pressure chamber is configured such that the working fluid simultaneously exerts the charge pressure on the first and second fluid displacement members.