Dual stage pump system with pre-stressed diaphragms and reservoir

A dual stage pump system for pumping and filtering high viscosity fluids, the system comprising:

• a first pump for pumping fluid from an input source through a filtering media and into a reservoir,
• the filtering media disposed between the first pump and the reservoir, the first pump being capable of pumping liquid through the filtering media to the reservoir,
• the reservoir disposed between filtering media and a second pump, the second pump being capable of withdrawing liquid from the reservoir, the reservoir providing filtered fluid to the second pumping means,
• the second pump pumping fluid received from the reservoir means through a discharge outlet of said second pump,
• a controller for monitoring and controlling the operation of said system, said controller being settable to operate said first and second pumps at predetermined pumping rates and to a predetermined quantity of fluid to be dispensed by said second pump, said controller having the ability to receive data indicating the pressure of fluid in said reservoir, said controller activating said first pump based upon said pressure.

A dual stage pump system for pumping and filtering high viscosity fluids, the system comprising:

• a first pumping means for pumping fluid from an input source through a filtering means and into a reservoir means,
• the filtering means disposed between the first pumping means and the reservoir means, the first pumping means being capable of pumping liquid through the filtering means to the reservoir means,
• the reservoir means disposed between filtering means and a second pumping means, the second pumping means being capable of withdrawing liquid from the reservoir means, the reservoir means providing filtered fluid to the second pumping means,
• the second pumping means pumping fluid received from the reservoir means through a discharge outlet,
• wherein the discharge outlet of the second pumping means is connected to a three-way valve, said valve having at least two alternative positions including one position in which the discharge outlet is in communication with a dispensing outlet, and a second position in which the discharge outlet is in communication with a recirculation conduit,
• the recirculation conduit being in communication with the input source to the first pumping means.