Vehicle windshield cleaning system

Abstract

Apparatus and method for providing a heated cleaning fluid to a vehicle surface. The apparatus has an inlet port for receiving an amount of fluid; an outlet port for dispensing an amount of heated fluid; a heating element coil or tube covered with a plastic sheath that heats up fluid passing from the inlet to the outlet; and a control circuit for energizing at least a portion of the heating element with a voltage to heat the fluid passing from the inlet to the outlet. The apparatus also has expandable and compressible features and parts for protection against freezing.

1 . Apparatus for providing a heated cleaning fluid to a vehicle surface comprising:
 a) an inlet port for receiving an amount of fluid;   b) an outlet port in fluid communication with the reservoir for dispensing an amount of heated fluid;   c) a metal heater coil having an interior passageway for heating fluid that passes from the inlet to the outlet port through said passageway; wherein the heater coil is covered, at least in part by an elastic material for containing fluid in the event of a ruptured heating element caused by one or more freeze/thaw expansion and contraction cycles; and   d) a control circuit for energizing at least a portion of the metal heating coil with a voltage to heat the heating element and the fluid passing from the inlet to the outlet.   
   
   
       2 . The apparatus of  claim 1  comprising:
 a) a fluid reservoir; and   b) a plurality of heater coils covered with the elastic material through which fluid can flow wherein the heater coils are in thermal communication with the fluid reservoir.   
   
   
       3 . The apparatus of  claim 2  wherein the fluid reservoir is plastic and includes an expandable portion or portions that expands when fluid in the reservoir freezes to prevent damage to the reservoir. 
   
   
       4 . The apparatus of  claim 1  wherein the fluid reservoir is made of a material that flexes to expand during freezing. 
   
   
       5 . The apparatus of  claim 1  comprising a pump for pumping fluid through the heating metal heating coil. 
   
   
       6 . The apparatus of  claim 5  wherein the pump is comprised of a motor driving a single shaft. 
   
   
       7 . The apparatus of  claim 2  wherein thermal communication between the heater coils and the reservoir occurs through an encapsulant that is thermally conductive to transfer heat between the heater coils and the reservoir. 
   
   
       8 . The apparatus of  claim 7  wherein the encapsulant also acts to retain heat to provide sustained heating of the reservoir when electrical energy is not being applied. 
   
   
       9 . The apparatus of  claim 2  comprising a heat dissipating device that thermally conducts heat into the fluid contained in the reservoir to provide additional heating of the fluid therein. 
   
   
       10 . The apparatus of  claim 9  wherein the heat dissipating device comprises a power FET that is supplied with a variable gate voltage by the control circuit. 
   
   
       11 . The apparatus of  claim 10  wherein the control circuit divides a total power into a percentage of applied power to each of the heater coils and power FET as a means of controlling the speed of heating of each based on the demand for fast heating of fluid or heating of reserve fluid. 
   
   
       12 . The apparatus of  claim 2  wherein the two heater coils are isolated in order to prevent electrical shorting. 
   
   
       13 . The apparatus of  claim 12  wherein the heater coils are isolated by a plurality of plastic spacing members either connected integrally with the enclosure or attached as separate connecting parts of the heating element assembly. 
   
   
       14 . The apparatus of  claim 1  comprising two heater coils, each constructed from an electrically conductive tube connected in series and further comprising a reservoir connected to the heater coils by means of sealed fittings. 
   
   
       15 . The apparatus of  claim 14  wherein the sealed fittings are metal adapters that are coupled to the heater coil by means of flaring the tubing ends and securing in place with a threaded fastener. 
   
   
       16 . The apparatus according to  claim 1 , wherein the heater coil has an outer surface spaced from the elastic material so that a heating fluid is routed both inside and outside the metal wall of said heater coil. 
   
   
       17 . The apparatus of  claim 16  wherein the elastic material comprises a larger diameter tube fixed loosely over the heater coil to capture fluid flowing along an outside surface of the heater coil. 
   
   
       18 . The apparatus according to  claim 17 , wherein the larger diameter tube fixed loosely over the heater coil is an electrically non-conductive material with elastic properties that is expandable during freeze conditions, thereby preventing breakage and loss of fluid and system functionality. 
   
   
       19 . The apparatus of  claim 1  additionally comprising a probe for sensing alcohol content of fluid entering the inlet port. 
   
   
       20 . A method for providing a heated cleaning fluid to a vehicle surface comprising:
 a) coupling an electrically conductive fluid carrying tube to a source of cleaning fluid;   b) routing a cleaning fluid into an inlet port of the tube such that the fluid flows from the inlet to an outlet port of said tube;   c) energizing said tube with a voltage to heat the fluid carrying tube and the fluid passing through the tube;   d) directing the fluid from the outlet port to a nozzle for dispensing heated fluid against said surface; and   e) covering at least a portion of the fluid carrying tube with an elastic material to contain fluid in the event of a ruptured tube caused by one or more freeze/thaw expansion and contraction cycles.   
   
   
       21 . The method of  claim 20  wherein said tube is energized with said voltage through a power switch FET by supplying a variable gate voltage to said FET to determine an amount of heat to be dissipated by said FET and wherein said FET is positioned proximate said tube such that said fluid in said tube acts as a heat sink for said power switch. 
   
   
       22 . The method of  claim 20  wherein about 150 ml of heated fluid is dispensed against said surface. 
   
   
       23 . The method of  claim 20  wherein the elastic material is a plastic tube having an inner diameter that is larger than an outside diameter of the conductive fluid carrying tube and further wherein fluid is routed with a region between the inner diameter of the plastic tube and the outer diameter of the conductive fluid carrying tube. 
   
   
       24 - 30 . (canceled) 
   
   
       31 . A method for providing a heated cleaning fluid to a vehicle surface comprising:
 a) covering an electrically conductive heating element with a flexible plastic tube having an elongated length sufficient to heat fluid passing through the flexible plastic tube;   b) routing a cleaning fluid into an inlet port of the plastic tube such that the fluid flows from the inlet to an outlet port of said tube;   c) energizing the heating element to heat the fluid passing through the tube;   d) directing the fluid from the outlet port of the tube to a nozzle for dispensing heated fluid against said surface.   
   
   
       32 . The method of  claim 31  wherein the heating element is an elongated member having electrical contacts at either end which extends through the plastic tube. 
   
   
       33 . The method of  claim 31  wherein the heating element is an elongated metal tube through which fluid is routed so that fluid contacts and is heated by both and inside and outside of the metal tube. 
   
   
       34 . A method for providing a heated cleaning fluid to a vehicle surface comprising:
 a) coupling a source of cleaning fluid to a heating vessel;   b) routing a cleaning fluid into an inlet of the heating vessel such that the fluid flows from the inlet to an outlet of said vessel;   c) heating fluid in the heating vessel as it passes from the inlet to the outlet;   d) directing the fluid from the outlet to a nozzle for dispensing heated fluid against said vehicle surface; and   e) activating a motor in response to the user activating a switch to dispense heated fluid from a nozzle and provide wiping action of wipers.   
   
   
       35 . The method of  claim 34  wherein a single motor is activated in response to the user activating a switch, said single motor pumping fluid into the heating vessel, dispensing heated fluid from a nozzle, and providing motive power for wiping action of wipers. 
   
   
       36 . The method of  claim 35  wherein an output from the single motor is coupled to a pump impeller by means of a clutch to allow separate control over pumping of fluid and wiper motion. 
   
   
       37 . The method of  claim 34  comprising coupling an output from a single motor to a wiper arm through a reducing gear to produce back and forth motion of one or more wiper blades. 
   
   
       38 . The method of  claim 34  wherein the vessel comprises a bent metal tube and the heating of fluid in said tube is performed by energizing the metal tube. 
   
   
       39 . The method of  claim 34  wherein pumping of fluid is prevented when the wiper arms/blade are not able to move.