US Patent 8449267 Pump assembly and fluid metering unit

Apparatus for a pump assembly and a fluid metering unit. The pump assembly can include a diaphragm with a portion of a body being molded over a portion of each one of a plurality of pistons. The pump assembly can include a wobble plate, a lower housing, and a spring positioned between the wobble plate and the lower housing. A valve housing can include pumping chambers with side walls that are angled. The fluid metering unit can include a bayonet locking mechanism and/or a seal between a housing and a flow meter. The controller can be calibrated according to the type and/or temperature of the fluid.