Vehicle window washer with washer fluid temperature responsive pressure control
AssigneeGeneral Motors Corporation
InventorsElgin J. Karklins, Stephen J. Scroggie, Steven L. Tracht, Mark W. Striker
Life of this patent
Estimating the term…
Abstract
A vehicle window washer in which the pump outlet pressure is varied in an inverse manner with temperature of the washer fluid so as to maintain a more consistent fluid deposit on the window as fluid viscosity changes with temperature. In particular, it uses a motor driven pump which provides a higher pump outlet pressure with the motor driven in a first direction than with the motor driven in the opposite direction and switches activation of the motor between the two directions based on sensed temperature of the fluid in the washer fluid reservoir.
Claims8
A window washer system for a vehicle having a window, the window washer system comprising, in combination:
- a washer fluid reservoir containing a washer fluid with a viscosity varying inversely with temperature;
- a nozzle directed at the window;
- a conduit from the reservoir to the nozzle;
- a motor driven pump effective to pump washer fluid from the reservoir through the conduit and nozzle to the window, the motor driven pump having a first mode of operation in which it generates a first pump outlet pressure and a second mode of operation in which it generates a second pump outlet pressure less than the first pump outlet pressure;
- a temperature sensor responsive to a temperature in the vicinity of the washer fluid reservoir so as to generate a temperature signal indicative of the temperature of washer fluid;
- and
- electric circuit means responsive to the temperature sensor to activate the motor driven pump in the first mode of operation with the temperature signal within a first temperature range and to activate the motor driven pump in the second mode of operation with the temperature signal within a second temperature range higher than the first temperature range, whereby the pump outlet pressure is automatically adjusted for the temperature dependent viscosity of the washer fluid.
Dependencies are inferred from the claim text.