Scrub water heating system for floor cleaner

Abstract

In a mobile floor sweeper/scrubber, a closed hydraulic system directs hydraulic fluid, or oil, to power various subsystems, such as the drive, steering, sweeping, scrubbing, etc., subsystems, which results in heating of the hydraulic fluid to an elevated temperature. The heated hydraulic fluid is provided to a heat exchanger, to which is also providing the scrub water for heating the water prior to application to the floor for improved, more efficient cleaning of the floor. This arrangement allows for the use of higher scrub water temperatures without using a dedicated system limited to the generation of higher scrub water temperatures, or without operating the sweeper/scrubber's drive motor at elevated temperatures higher than its specified normal operating temperature. The use of heated or ambient scrub water can be selected as desired by the sweeper/scrubber operator.

What is claimed is: 
     
         1 . For use in a mobile floor sweeper/scrubber having plural operating systems including a scrubbing system, apparatus for heating scrub water applied to the floor to an elevated temperature comprising:
 a scrub water reservoir;   a hydraulic fluid reservoir;   a heat exchanger coupled to said scrub water reservoir via a first water line and to said scrubbing system via a second water line for providing scrub water to said scrubbing system, said heat exchanger further coupled to said operating systems via a first hydraulic fluid line and to said hydraulic fluid reservoir via a second hydraulic fluid return line; and   a hydraulic pump coupled to said hydraulic fluid reservoir and to said operating systems for providing hydraulic fluid from said hydraulic fluid reservoir to said operating systems, wherein the hydraulic fluid is heated to an elevated temperature by said operating systems, with the heated hydraulic fluid then provided to said heat exchanger for heating the scrub water to an elevated temperature with the heated scrub water then provided to said scrubbing system from said heat exchanger.   
     
     
         2 . The apparatus of  claim 1  further comprising control means coupled to said first hydraulic fluid line and to a by-pass line coupled to said first hydraulic fluid line, wherein the heated hydraulic fluid from said operating systems may be selectively directed to said heat exchanger for providing heated scrub water to the scrubbing system or the heated hydraulic fluid may by-pass the heat exchanger and be provided to said hydraulic fluid reservoir via said second hydraulic fluid return line for providing ambient water to the scrubbing system. 
     
     
         3 . The apparatus of  claim 2 , wherein said control means includes a manual control. 
     
     
         4 . The apparatus of  claim 3 , wherein said manual control is a solenoid valve. 
     
     
         5 . The apparatus of  claim 1 , wherein said first hydraulic fluid line and said second water line are coupled to respective adjacent portions of said heat exchanger. 
     
     
         6 . The apparatus of  claim 5  further comprising a first inlet port coupling said first hydraulic fluid line to said heat exchanger and a first outlet port coupling said second water line to said heat exchanger, wherein said first inlet port coupling and said first outlet port coupling are disposed adjacent one another on said heat exchanger. 
     
     
         7 . The apparatus of  claim 6  further comprising a second outlet port coupling said hydraulic fluid return line to said heat exchanger and a second inlet port coupling said first water line to said heat exchanger. 
     
     
         8 . The apparatus of  claim 1 , wherein the hydraulic fluid is heated to a temperature on the order of 200° F. 
     
     
         9 . The apparatus of  claim 8 , wherein the scrub water is heated to a temperature on the order of 140° F. 
     
     
         10 . The apparatus of  claim 1 , wherein said heat exchanger includes first and second opposed ends, said system further comprising a first pair of inlet and outlet ports respectively coupling said first hot hydraulic fluid line and said second hydraulic fluid return line to said first and second ends of said heat exchanger, and a second pair of outlet and inlet ports respectively coupling said second water line and said first water line to said first and second ends of said heat exchanger. 
     
     
         11 . The system of  claim 10 , wherein said heat exchanger further includes said first and second plural spaced channels extending between the first and second opposed ends of said heat exchanger for respectively carrying scrub water and hydraulic fluid. 
     
     
         12 . The system of  claim 11 , wherein said first and second channels are disposed in intimate contact with one another and are arranged in an alternating manner within said heat exchanger. 
     
     
         13 . The system of  claim 1 , wherein said heat exchanger is comprised of a high heat conducting metal, or of a high heat conducting plastic, ceramic or composite material. 
     
     
         14 . The system of  claim 1  further comprising thermal insulation disposed about and in contact with said heat exchanger. 
     
     
         15 . The system of  claim 1 , wherein the scrub water and the hydraulic fluid flow in opposite directions within said heat exchanger.