The construction of a washer pump involves several components working together to create fluid movement. The heart of the washer pump is a small DC motor that provides rotational energy. This motor in the washer pump is specifically designed for intermittent duty rather than continuous operation, matching the typical usage pattern of windshield washing. The motor shaft of the washer pump extends into the pump chamber where it connects to an impeller. The materials used in these washer pump components are selected for compatibility with washer fluids and resistance to temperature variations.
The impeller design is crucial to the performance of a washer pump. Most washer pump units utilize a centrifugal impeller with curved blades that sling fluid outward when rotating. This action creates pressure that forces fluid through the washer pump outlet. The housing surrounding the impeller in a washer pump is precisely shaped to direct fluid flow efficiently. Some washer pump designs incorporate a small filter screen to prevent debris from entering and potentially damaging the impeller mechanism. These design elements work together to determine the flow rate and pressure characteristics of the washer pump.
Electrical connections and sealing are important aspects of washer pump design. The electrical connector on a washer pump is typically designed with a gasket or O-ring to prevent moisture intrusion. The wires leading into the washer pump are sealed where they enter the housing to maintain waterproof integrity. Inside the washer pump, brush-type motors are common, though some modern designs use brushless technology for extended service life. The electrical components of the washer pump must withstand the variable voltages present in automotive electrical systems while drawing current appropriate for the vehicle's wiring capacity.
Materials science plays a significant role in washer pump manufacturing. The housing of a washer pump is commonly made from plastics that resist chemical degradation from washer fluid additives. The impeller material in a washer pump must maintain dimensional stability across temperature extremes while resisting wear from fluid movement. Seals and gaskets in a washer pump are formulated from rubber compounds that remain flexible in cold weather and resist swelling when exposed to washer fluid chemicals. These material considerations contribute to the reliability and longevity of the washer pump in diverse operating conditions.
