PUMP ASSEMBLIES WITH FREEZE-PREVENTIVE HEATING

摘要

Pumps are disclosed that include a pump housing and at least one movable pumping element situated in the housing. The pumping element(s) are magnetically driven by magnetically coupling an external magnet driver (e.g., a stator) to a driven magnet located in the housing. A control circuit selectively operates the stator and a heat-producing element, so as to energize the heat-producing element especially in a potential freezing condition when the pump is not being otherwise operated. Thus, the fluid in the pump is prevented from freezing, and freeze-related pump damage is avoided. The heat-producing element can be the stator itself energized differently from when the stator is used for driving the pump.