US3645420A

US3645420A - High-pressure hot water cleaner

Info

Publication number: US3645420A
Application number: US835586A
Authority: US
Inventors: Joseph G Machado
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-06-23
Filing date: 1969-06-23
Publication date: 1972-02-29
Anticipated expiration: 1989-02-28

Abstract

Cleaning apparatus having a tank of hot medium from which heat is transferred to a cleaning fluid conducted through a coiled heat transfer tube. Cold cleaning fluid is delivered by a continuously operative liquid pump to the heat transfer tube from which the heated and pressurized cleaning fluid is delivered to a spray gun having a trigger for initiating an automatic multistage cycle to sequentially spray a surface with water, detergent and a mixture thereof at elevated temperatures.

Description

g a l 4 l Minted metres Patent [151 mnemm lt/tlaelltntlo 1 Felt, 29, 11.972

[54] llllllGlHl-WRE5SKUIRE HUT WATER 2,128,263 8/1938 Ofeldt ..137/336 X @LIEAWER 2,165,321 7/1939 Wertz "222/146 HA 2,884,197 4/1959 Wh'ttell, Jr. ..237 8 BP [72] lnventor: Joseph G. Maehado, R0. Box 371 l, l Modesto 95 352 Primary Examiner-Robert B. Reeves 22 i June 23, 9 9 Assistant ExaminerJ0hn P. Shannon [21] A l N 835 M Attorney-Owen, Wiclcersham 8L Erickson [57] AlEiS'llllilAtC'l [52] US. Cl, ..222/23, 222/146 ll-l, 1765/104 Cleaning apparatus having a tank of hot medium from which [51] h heat is transferred to a cleaning fluid conducted through a [58] fi gj g"546335) 5 1 9 coiled heat transfer tube. Cold cleaning fluid is delivered by a 131 continuously operative liquid pump to the heat transfer tube from which the heated and pressurized cleaning fluid is delivered to a spray gun having a trigger for initiating an auto- [56] References Cited matic multistage cycle to sequentially spray a surface with UNITED STATES PATENTS water, detergent and a mixture thereof at elevated temperatures. 2,000,467 5/1935 Lindseth ..l65/l04 X 2,582,134 1/1952 Kimmell et a1 ..l65/l04 X 16 Cilaims, 13 Drawing Figures PATENTEDFEBEQ I972 13, SARA-2O SHEET 2 OF 5 PATENTEUFEBZQ 1972 3,6W5A2O SHEET 3 OF 5 ELEASAZO PATENTEDFEB29 |972 SHEET UF 5 HIGH-PRESSURE HGT WATIER (CLEANER This invention relates to apparatus for applying sprays of cleaning fluid under elevated pressures and temperatures.

An important object of the present invention is to provide power-operated apparatus through which heated cleaning fluid may be delivered in spray form at predetermined temperature and pressures under safe and trouble-free conditions and in selectively controlled amounts.

In accordance with the present invention the cleaning fluid is heated to its elevated delivery temperature by being con ducted through a coiled heat transfer tube submerged within a body of heating fluid stored within an insulated tank. The cleaning fluid is delivered to the tank under pressure by a liquid pump which is continuously operative to supply the cleaning fluid only at a lower temperature. Less frequent breakdown and maintenance is therefore required for the pump. Solenoid-controlled valves are also associated with the apparatus for selectively introducing a cleaning fluid such as a detergent solution into the water continuously delivered by the pump to the heat transfer tube. A solenoid operated bypass control valve is also provided so that the cold liquid may be directly delivered to the outlet end of the heat transfer tube. A flexible conduit connects the outlet to a spray gun which has a trigger-operated switch through which the operator may selectively and sequentially control the supply of cold liquid, hot liquid, and detergent to the spray gun.

These together with other objects and advantages which will become subsequently apparent reside in the details of con struction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIG. I is a top plan view of one form of apparatus constructed in accordance with the present invention.

FIG. 2 is a side sectional view through the apparatus taken substantially through a plane indicated by section line 2-2 in FIG. I.

FIG. 3 is a front elevational view of the apparatus shown in FIGS. I and 2.

FIG. 3 is a schematic diagram of the heating device associated with the apparatus of FIGS. 1-3.

FIG. 5 is a partial top plan view of another form of cleaning apparatus constructed in accordance with the present invention.

FIG. 6 is a side sectional view taken substantially through a plane indicated by section line t5h in FIG. 5.

FIG. 7 is a partial side sectional view showing a third form of the invention.

FIG. fl is a top plan view of a fourth form of the invention.

FIG. 9 is a partial front elevational view of the apparatus shown in FIG. b.

FIG. III is a side sectional view taken substantially through a plane indicated by section line IIII0 in FIG. 8.

FIG. II is a schematic view of the heating device associated with the apparatus of FIGS. til-ill.

FIG. I2 is a side elevational view with parts shown in section of the spray gun and control box associated with the apparatus of the present invention.

FIG. I3 is an electrical circuit diagram associated with the controls shown in FIG. I2.

Referring now to the drawings in detail, and initially to FIGS. I, 2 and 3, the cleaning apparatus generally denoted by reference numeral Id may be rendered portable by mounting on a wheeled vehicle frame 12. In one embodiment of the in vention, a generally rectangular frame 12 is supported by a pair of rear wheel assemblies I4 and a pair of forward caster wheel assemblies lid. A pulling rod I8 may be pivotally con nected to the forward end of the vehicle frame. The forward end may also mount a vertical rack 2d on which flexible hose 22 may be stored, the hose 22 being connected to a spray gun device 24 as shown in FIG. I2 and to a control box 26 having a plurality of operational stage indicatorsltl, 3b, 32, and 34.

With continued reference to FIGS. I and 2 in particular, it will be noted that a vertical insulated tank lid is fixedly mounted on the vehicle frame adjacent the forward end. The upper opened end of the tank may be closed by a conical exhaust dome 3?). An outlet fitting II! is mounted by the tanlt ad jacent its upper end and projects therefrom forwardly. The flexible, fluid delivery hose 22 is connected to the fitting lb.

The outlet fitting Ml projects into the tank above a body of heat-storing fluid, such as water d2 and is connected by a T- coupling 44 to the outlet end of an externally finned and coiled heat transfer tube in. The end of the heat transfer tube 46 opposite the outlet end to which the coupling is con nected, is connected to an inlet fitting fixedly mounted by the tank 36. It will be apparent therefore, that cleaning fluid conducted through the heat transfer tube d6 will be elevated in temperature by transfer of heat from the heat-storing water 42. The temperature of the body of water $2 is maintained at a predetermined value by means of a thermostatic sensing element d3 fixedly mounted by the tank and projecting into the water.

The temperature of the heat storing water is heated by means of a heating assembly which includes a pair of gas bur ners 50 that extend horizontally through an enclosing jacket 52 at the bottom of the tank 35 as more clearly seen in FIG. 2. A plurality of vertical flue gas conduits fi l communicate with the interior of the jacket 52 and conduct flue gas upwardly therefrom through the interior of the tank in heat transfer relation to the body of water d2, in order to maintain the same at its elevated temperature. By controlling the supply of fuel to the burners 52, the temperature of the flue gases and the water I?! may be regulated. Accordingly, as shown in FIG. il, the fuel or gas for the burners is supplied through an inlet valve 5d and a pair of parallel flow valves 58 and 649 to the burners. The flow valves 58 and 6d regulate the quantity of fuel supplied to the burners. Further, the quantity of fuel conducted through the valve as may be varied under control of the thermostatic sensing element t! aforementioned. Accordingly, when the temperature of the heat-storing water 4 2 within the tank reaches a predetermined upper limit, this temperature is sensed by the element Ali so as to close the flow valve db thereby reducing the quantity of fuel supplied to the burner. If the temperature of the water I2 drops below a lower limit, as sensed by the element dd, the valve M9 is opened so as to increase the quantity of fuel supplied to the burners and the amount of heat generated thereby.

The cleaning fluid is supplied to the inlet fitting 4% on the tank at a relatively low inlet temperature by means of a delivery conduit is in turn connected by a solenoid-operated bypass valve assembly 64 to a pump discharge conduit 6h. The conduit es is connected to the discharge end of a liquid pump dd, the inlet end being connected by a fitting 7b to a suitable source of water. The pump 658 may be continuously maintained in operation by means of a motor 72 which is fixedly mounted on the vehicle frame I2 adjacent its rear end below the pump A supporting platform 7 5 fixedly mounts the pump 68 in spaced relation above the motor 52 which is drivingly connected to the pump by means of an endless drivebelt 76. Thus, in one operative condition of the solenoid operated valve assembly Ml, cold water under pressure is delivered by the pump 46% through conduits dd and s2 to the inlet end of the heat transfer tube ltia through inlet fitting 418. In the other operative position of the solenoid-operated valve assembly b4, the cold water is delivered from conduit as and valve assembly 64 to a bypass conduit 78 which is directly connected to the outlet fitting id through the coupling id thereby bypassing the heat transfer tube. 46 by means of which the cleaning fluid is elevated in temperature.

A solenoid-controlled device till! is also provided as shown in FIGS. I and 2 having an intake conduit b2 drawing a cleaning fluid such as detergent tldfrom a container b6 fixedly mounted on the vehicle frame between the motor 72 and the tanl; 3th. Wen operating, the solenoid-controlled device bill will introduce the detergent into the conduit :66 through fitting dd.

Thus, cold water, hot water and a mixture of cold or hot water and detergent may be selectively delivered to the spray gun 24 by the flexible hose 22.

FIGS. 5 and 6 illustrate one modification of the apparatus previously described, generally referred to by reference numeral It). The apparatus it) includes a stationary frame 12 which mounts all of the components hereinbefore described in connection with FIGS. 1 through 4 except for the heating facility for the heat-storing water 42 within the insulated tank 36. Instead of a gas burner type of heating facility, a coiled heating conduit 90 is mounted within the tank inside of the coiled configuration of the heat transfer tube 46' through which the cleaning fluid is conducted from the conduit 62 to the outlet fitting ill). The heating conduit 90) is connected by a central conduit portion 92 to an inlet fitting 94 while the upper end of the heating conduit is connected to an outlet fitting 96. A heating fluid which is heated externally of the apparatus may thereby be circulated through the heating conduit 90 in order to regulate and maintain the elevated temperature of the heat-storing water 42 under control of the thermostatic sensing element 48.

The body of heat-storing water 42 may alternatively be heated externally of the apparatus and circulated through the tank 36, in which case, the level of the water within the tank will be controlled by a float valve 98 as shown in FIG. 7 illustrating a third form of the invention. When heating the water externally of the apparatus through any suitable heating means, the apparatus may be lightened by taking advantage of a suitable heating facility that may be available.

Referring now to FIGS. 8, 9 and 10, another form of apparatus generally referred to by reference numeral 100 is shown. The apparatus we includes a frame assembly I02 which supports a horizontally positioned, cylindrical tank I04 vertically spaced above a supporting floor M96. A heat-insulating jacket I08 surrounds the tank between axial end plates I and H2. Chamber forming closures 114 and H6 are hingedly connected to the axial ends of the tank and may be opened for component repair and replacement purposes. The closure 114. at one axial end of the tank internally mounts a burner assembly 118 within an air inlet chamber 120 which is partitioned by wall 1122 from an exhaust chamber 124 to which an exhaust conduit 126 is connected. Also, mounted on the closure IE4 is a blower device 128 having a discharge conduit 1130 in communication with the chamber 120. The other closure I16 encloses at the opposite axial end of the tank, a flow return space 132.

A plurality of elongated, heat transfer tubes 134 extend between and are supported by the end plates Ill) and 112 for conducting flue gas from the inlet chamber I20 to the return chamber 132. The flue gas which is the product of combustion of the fuel supplied to the burner assembly I18, will be at a very high temmrature. Accordingly, as this flue gas flows through the heat transfer tubes 134, it heats the heat-storing fluid 2136 which is sealed within the tank between the end plates 1110 and 132. The flue gas reaching the return chamber 132 then travels in a return direction through another set of heat transfer tubes I38 to the exhaust chamber 3124. Thus, the flue gas undergoes bidirectional flow through the tank between the inlet chamber 126 and the exhaust chamber 124 under the inducement of the blower 128. The heat stored within the fluid 136 is transferred to the cleaning fluid conducted through an externally finned, coiled heat transfer tube 1 M) encircling some of the heat transfer tubes E34 and 138 as shown in FIG. 10 in order to elevate the temperature of cleaning fluid.

Mounted below the horizontally disposed tank 104, on the frame assembly 192, is a liquid pump 68' similar in operation and construction to the pump 68 hereinbefore described in connection with FIGS. 1-4. The pump is driven through a direct drive coupling M2 by an electric motor 72 in order to continuously supply cold water under pressure to the discharge conduit 66. Detergent may be introduced into the water through the fitting 88' connected to the solenoidoperated device fit). The detergent 84 is drawn from the container 86' through conduit 82. Water or a mixture of water and detergent is supplied to the inlet end of the coiled heat transfer tube Ml through the bypass control valve assembly 64' which is also connected by the bypass conduit 78' directly to the outlet end of the coiled heat transfer tube Mt). The outlet end of the heat transfer tube Mil: is connected by an outlet fitting 410 as shown in FIGS. 8 and 9 to the flexible hose 22 for delivery of cleaning fluid to the spray gun.

The source of heat for the apparatus is obtained from the burner assembly 1114 to which a regulated and controlled quantity of fuel is supplied as shown in FIG. II in a manner similar to that hereinbefore described in connection with FIG. 4. Accordingly, the fuel is admitted through an inlet valve 56' and conducted through a pair of parallel flow-regulating valves 53 and 6t? to the burner assembly 114. A thermostatic sensing element 48' controls the opening and closing of the flow control valve 61) in order to change the quantity of fuel fed to the burner assembly and the amount of heat generated thereby.

Referring now to FIG. )12 it will be observed that the spray gun device 24 is of a conventional type having a trigger element 144 which in addition to opening a valve to permit discharge of cleaning fluid, as in the case of a conventional spray gun, also actuates an electrical switch M6 as shown in the electrical circuit diagram of FIG. 13, to automatically produce a sequential change in operation as indicated by extinction of one of the indicator lamps 28, 3t), 32 and 34 and illumination of another of the indicator lamps. Thus, the cleaning fluid from the outlet fitting of the heating tank is connected by the flexible hose 22 to a special flexible conduit M8 by means of a fitting I50 conducting the cleaning fluid in surrounding relation to an electrical cable 152 through which the trigger-operated switch associated with the spray gun is connected to the control box 26 on which the indicator lamps are mounted.

As shown in FIG. 13, a DC source of electrical voltage is connected to the control box on which the indicator lamps are mounted by the positive voltage line I54 and the negative voltage line 156. Each indicator lamp is electrically connected to one of the four electronic shift registers E53 mounted within the control box. Upon momentary closing of the trigger-operated switch 146, a first relay is energized so as to open the normally closed relay switch 162 disconnecting the positive-voltage line I54 from an input signal line I64. At the same time, normally opened relay switch 1166 is closed so as to supply a positive voltage to the shift line 163. In this fashion, each time the switch 146 is closed, a shift signal is established in order to cause a shift from one operational stage to another, in view of the electrical interconnection between the shift registers 158 corresponding to each operational stage. When an operational shift occurs, the indicator lamp of a preceding shift register is extinguished and the lamp associated with the following shift register illuminated.

Each of the shift registers I58 are commercially available components, the terminals of which are wired into the circuit as shown in FIG. 13 in order to control operation of the apparatus. The first stage shift register transfers the stage-changing signals to the other shift registers which in turn control energization of the relays I70, 1'72 and 174 as each signal pulse is generated by momentary closing of switch I46. Energization of the relay I'7lll closes the normally opened relay switch 176 so as to complete a circuit through the hot rinse control solenoid 173 between the

voltage lines

54 and 156. Solenoid 178 is associated with the bypass valve assembly 64 as described in connection with FIGS. 1 through 4 for example. Thus, when the solenoid 178 is energized, cold water delivered by the pump 68 is routed through conduit 62 to the heat transfer tube 46. When the solenoid B78 is deenergized, cold water is supplied directly through bypass conduit '78 to the outlet fitting 40.

Energization of the relay E72 closes the normally opened relay switches 180 and $82 to simultaneously energize the hot rinse solenoid i178 and the detergent solenoid llll l associated with the detergent supply device as. Thus, when the relay N2 is energized, heated detergent will be supplied to the spray gun device. linergization of the relay lid on the other hand, closes the normally open relay switch to complete an energizing circuit only through the detergent solenoid llld l for delivery of cold detergent,

From the foregoing description, it will be apparent that the operator may produce a change in operation by actuation of the trigger element M4 associated with the spray gun device causing an operational shift in accordance with an automatic sequence for which the shift registers llfih are programmed. 'lhus, through the control circuit described, the hot rinse solenoid lli'lil and detergent solenoid lldd may be energized and deenergized in different combinations in order to sequentially supply cold water, hot water, hot detergent and cold detergent to the outlet for discharge from the spray gun and then automatically reset for a new cycle. 80 that the operator will liIIOW what type of cleaning fluid is being discharged at any instant from the spray gun, one of the indicator lamps will be illuminated corresponding to the operational stage of the apparatus. Further, while injection of the detergent into the water is disclosed upstream of the heat transfer tube, the present invention contemplates injection of detergent downstream of the heat transfer tube as well.

The foregoing is considered as illustrative only of the principles ol" the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

i. A cleaning apparatus, comprising an insulated tank supported in vertical position, containing a body oi" water,

a heat transfer conduit mounted within the tank in heatconductive relation to the water and comprising a coiled tube having external heat-conducting fins,

outlet means mounted on the tanlr and connected directly to said heat transfer conduit for discharging liquid at a predetermined temperature and pressure,

continuously operative pump means for supplying liquid to the heat transfer conduit at an inlet temperature substan tially lower than said predetermined temperature,

bypass means for selectively conducting the liquid supplied by the pump means at said inlet temperature directly to the outlet means while preventing flow through the heat transfer conduit,

a source of cleaning fluid,

selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid to the heat transfer conduit, and

heating means mounted within the tank and disposed inwardly of tire coiled tube, said heating means including fuel burner means, a plurality of fuel supply tubes connected to the burner means, temperature-controlling valve means controlling flow of fuel through at least one of the supply tubes, and thermostatic sensing means mounted by the tanlr within the water for operating the temperature-controlling valve means.

The combination of claim It wherein the heat'uig means further includes heating conduits conducting flue gas from the burner means upwardly through the tanli.

A cleaning apparatus, comprising an insulated tank containing a body olheat-storing fluid,

a coiled tube having errternm heat-conducting tins mounted within the tanlr in heat-conductive relation to the heatstoring fluid,

outlet means mounted on the tank and connected directly to said coiled tube for discharging liquid at a predetermined tcrnpcrature and pressure,

continuously operative pump means for supplying liquid to said coiled tube at an inlet temperature substantially lower than said predetermined temperature,

bypass means for selectively conducting the liquid supplied by the pump means at said inlet temperature directly to the outlet means while preventing flow through said coiled tube,

a source or" cleaning fluid,

selectively controlled valve means connecting the source to the pump means for supplying a mixture or" fluid and the liquid to said coiled tube, and

heating means mounted within the tanlr and disposed inwardly oi the coiled tube, said heating means including fuel burner means, a plurality oi? fuel supply to corn nected to the burner means, temporaturecontrolling valve means controlling flow of fuel through at least one of the supply tubes and thermostatic sensing means mounted by the tank within the heatstoring liquid for operating the temperature-controlling valve means.

t. The combination of claim 33 wherein the heat' g means further includes a plurality of heating conduits conducting flue gas from the burner means horizontally through the tanlr, and blower means for inducing llow of said gens through the heating conduits.

5. A cleaning apparatus, comprising an insulated tanlr supported in a vertical position and con taining a body of water,

a coiled tube having external heat-conducting fins mounted within the tanlr. in heat-conductive relation to the water, outlet means mounted on the tanlr and connected directly to said coiled tube for discharging liquid at a predetermined temperature and pressure,

continuously operative pump means for supplying liquid to said coiled tube at an inlet temperature substantially lower than said predetermined temperature, and

a source of cleaning fluid,

selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid to said coiled tube, and

heating means within the tank and disposed inwardly of the coileo tube, said heating means including a coiled heating conduit through which a heating fluid circulated.

s. A cleaning apparatus, comprising an insulated tank containing a body of heat-storing fluid,

a coiled tube having external heat-conducting fins mounted within the tank in heat-conductive relation to the heatstoring fluid,

outlet means mounted on the tank and connected directly to said coiled tube for discharging liquid at a predetermined temperature and pressure,

heating means mounted within the tank and disposed inwardly of the coiled tube, and further including a plurality of heating conduits conducting t'lue from the heating means horizontally through the tanlt, and blower means for inducing flow oi? said flue gas through the heating conduits.

'l. A cleaning apparatus, comprising an insulated. containing a body of heat-storing fluid,

a coiled tube having external heat-conducting tins moun ted within the tanlr in heat-conductive relation to the heatstoring fluid,

a source of cleaning fluid, and

selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid to said coiled tube,

heating means mounted within the tank and disposed inwardly of said coiled tube, said heating means including fuel burner means, a plurality of fuel supply tubes connected to the burner means, temperature-controlling valve means controlling flow of fuel through at least one of the supply tubes and thermostatic sensing means mounted by the tank within the heat-storing liquid for operating the temperature-controlling valve means.

8. The combination of claim 7 wherein the selectively controlled valve means includes solenoid devices for respectively blocking flow of the cleaning fluid and conducting flow of the liquid in the outlet means in bypass relation to the heat transfer conduit, programmed means for energizing said solenoid devices in accordance with different operational stages, pulse-generating means connected to the program means for sequentially changing the operational stages, and indicator means connected to said programmed means for identifying the operational stages.

9. A cleaning apparatus, comprising an insulated tank containing a body of heat-storing fluid, a

heat transfer conduit mounted within the tank in heatconductive relation to the heat-storing fluid, outlet means mounted on the tank and connected directly to said heat transfer conduit for discharging liquid at a predetermined temperature and pressure, continuously operative pump means for supplying liquid to the heat transfer conduit at an inlet temperature substantially lower than said predetermined temperature, a source of cleaning fluid, and

selectively controlled valve means connecting the source to the pump means for supplying mixture of said fluid and the liquid to the heat transfer tube, the selectively controlled valve means including solenoid devices for respectively blocking flow of the cleaning fluid and conducting flow of the liquid in the outlet means in bypass relation to the heat transfer conduit,

programmed means for energizing said solenoid devices in accordance with different operational stages,

pulse-generating means connected to the programmed means for sequentially changing the operational stages, and

indicator means connected to said programmed means for identifying the operational stages.

10. A cleaning apparatus, comprising an insulated tank containing a body of a first liquid,

a heat transfer conduit mounted within the tank in heatconductive relation to said first liquid and having an inlet and outlet means,

pump means for supplying a second liquid to the heat transfer conduit at said inlet,

a source of cleaning fluid,

selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and said second liquid to the heat transfer conduit, and

heating means mounted within the tank for imparting heat to said heat transfer conduit, said heating means including fuel burner means,

a plurality of fuel supply tubes connected to the burner means,

temperaturecontrolling valve means controlling flow of fuel through at least one of the supply tubes, and

thermostatic sensing means mounted by the tank within the heat-storing liquid for operating the temperaturecontrolling valve means.

1].. The apparatus of claim 10 having bypass means for 5 selectively conducting said second liquid directly from said pump means to said outlet means.

12. in a cleaning apparatus having a tank containing a body of heat-storing fluid at a predetermined temperature,

a heat exchange tube in the tank in heat-conductive relation to the heat-storing fluid, with an inlet and an outlet,

pump means for supplying liquid to said tube at an inlet temperature substantially lower than said predetermined temperature,

fuel burner means in said tank,

a plurality of fuel supply tubes connected to the burner means,

temperature-controlling valve means controlling flow of fuel through at least one of the supply tubes,

thermostatic sensing means mounted by the tank within the heat-storing liquid for operating the temperature'controlling valve means,

a source of cleaning fluid, and

selectively controlled valve means connecting said source to said pump means for supplying a mixture of said fluid and said liquid to said tube.

13. A cleaning apparatus, comprising a tank containing a body of water,

a coiled tube mounted within the tank in heat-conductive relation to the water,

outlet means for discharging liquid from said coiled tube at a predetermined temperature and pressure,

pump means for supplying liquid to said coiled tube at an inlet temperature substantially lower than said predetermined temperature,

heating means within the tank and disposed inwardly of the coiled tube, said heating means including a coiled heating conduit through which a heating fluid is circulated, and

bypass means for selectively conducting the liquid supplied by the pump means at said inlet temperature directly to the outlet means while preventing flow through said coiled tube.

14. A cleaning apparatus, comprising a tank containing a body of water,

a coiled tube mounted within the tank in heat-conductive relation to the water,

heating means within the tank and disposed inwardly of the coiled tube, said heating means including a coiled heating conduit through which a heating fluid is circulated,

a source of cleaning fluid, and

selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid to said coiled tube.

15. A cleaning apparatus, comprising an insulated tank containing a body of heat-storing fluid,

a coiled tube mounted within the tank in heat-conductive relation to the heat-storing fluid,

heating means mounted within the tank and disposed inwardly of the coiled tube, and further including a plurality of heating conduits conducting flue gas from the heating means horizontally through the tank, and

blower means for inducing flow of said flue gas through the heating conduits.

16. A cleaning apparatus, comprising a tank containing a body of heat-storing fluid,

a heat transfer conduit mounted within the tank in heatconcluctive relation to the heat-string fluid and having outlet means for discharging liquid at a predetermined temperature and pressure,

pump means for supplying liquid to the heat transfer conduit at an inlet temperature substantially lower than said predetermined temperature,

a source of cleaning fluid, and

selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid to the heat transfer tube,

Claims

1. A cleaning apparatus, comprising an insulated tank supported in vertical position, containing a body of water, a heat transfer conduit mounted within the tank in heatconductive relation to the water and comprising a coiled tube having external heat-conducting fins, outlet means mounted on the tank and connected directly to said heat transfer conduit for discharging liquid at a predetermined temperature and pressure, continuously operative pump means for supplying liquid to the heat transfer conduit at an inlet temperature substantially lower than said predetermined temperature, bypass means for selectively conducting the liquid supplied by the pump means at said inlet temperature directly to the outlet means while preventing flow through the heat transfer conduit, a source of cleaning fluid, selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid to the heat transfer conduit, and heating means mounted within the tank and disposed inwardly of the coiled tube, said heating means including fuel burner means, a plurality of fuel supply tubes connected to the burner means, temperature-controlling valve means controlling flow of fuel through at least one of the supply tubes, and thermostatic sensing means mounted by the tank within the water for operating the temperature-controlling valve means.

2. The combination of claim 1 wherein the heating means further includes heating conduits conducting flue gas from the burner means upwardly through the tank.

3. A cleaning apparatus, comprising an insulated tank containing a body of heat-storing fluid, a coiled tube having external heat-conducting fins mounted within the tank in heat-conductive relation to the heat-storing fluid, outlet means mounted on the tank and connected directly to said coiled tube for discharging liquid at a predetermined temperature and pressure, continuously operative pump means for supplying liquid to said coiled tube at an inlet temperature substantially lower than said predetermined temperature, bypass means for selectively conducting the liquid supplied by the pump means at said inlet temperature directly to the outlet means while preventing flow through said coiled tube, a source of cleaning fluid, selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid to said coiled tube, and heating means mounted within the tank and disposed inwardly of the coiled tube, said heating means including fuel burner means, a plurality of fuel supply tubes connected to the burner means, temperature-controlling valve means controlling flow of fuel through at least one of the supply tubes and thermostatic sensing means mounted by the tank within the heat-storing liquid for operating the temperature-controlling valve means.

4. The combination of claim 3 wherein the heating means further includes a plurality of heating conduits conducting flue gas from the burner means horizontally through the tank, and blower means for inducing flow of said flue gas through the heating conduits.

5. A cleaning apparatus, comprising an insulated tank supported in a vertical position and containing a body of water, a coiled tube having external heat-conducting fins mounted within the tank in heat-conductive relation to the water, outlet means mounted on the tank and connected directly to said coiled tube for discharging liquid at a predetermined temperature and pressure, continuously operative pump means for supplying liquid to said coiled tube at an inlet temperature substantially lower than said predetermined temperature, and bypass means for selectively conducting the liquid supplied by the pump means at said inlet temperature directly to the outlet means while preventing flow through said coiled tube, a source of cleaning fluid, selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid tO said coiled tube, and heating means within the tank and disposed inwardly of the coiled tube, said heating means including a coiled heating conduit through which a heating fluid is circulated.

6. A cleaning apparatus, comprising an insulated tank containing a body of heat-storing fluid, a coiled tube having external heat-conducting fins mounted within the tank in heat-conductive relation to the heat-storing fluid, outlet means mounted on the tank and connected directly to said coiled tube for discharging liquid at a predetermined temperature and pressure, continuously operative pump means for supplying liquid to said coiled tube at an inlet temperature substantially lower than said predetermined temperature, bypass means for selectively conducting the liquid supplied by the pump means at said inlet temperature directly to the outlet means while preventing flow through said coiled tube, heating means mounted within the tank and disposed inwardly of the coiled tube, and further including a plurality of heating conduits conducting flue gas from the heating means horizontally through the tank, and blower means for inducing flow of said flue gas through the heating conduits.

7. A cleaning apparatus, comprising an insulated tank containing a body of heat-storing fluid, a coiled tube having external heat-conducting fins mounted within the tank in heat-conductive relation to the heat-storing fluid, outlet means mounted on the tank and connected directly to said coiled tube for discharging liquid at a predetermined temperature and pressure, continuously operative pump means for supplying liquid to said coiled tube at an inlet temperature substantially lower than said predetermined temperature, a source of cleaning fluid, and selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid to said coiled tube, heating means mounted within the tank and disposed inwardly of said coiled tube, said heating means including fuel burner means, a plurality of fuel supply tubes connected to the burner means, temperature-controlling valve means controlling flow of fuel through at least one of the supply tubes and thermostatic sensing means mounted by the tank within the heat-storing liquid for operating the temperature-controlling valve means.

9. A cleaning apparatus, comprising an insulated tank containing a body of heat-storing fluid, a heat transfer conduit mounted within the tank in heat-conductive relation to the heat-storing fluid, outlet means mounted on the tank and connected directly to said heat transfer conduit for discharging liquid at a predetermined temperature and pressure, continuously operative pump means for supplying liquid to the heat transfer conduit at an inlet temperature substantially lower than said predetermined temperature, a source of cleaning fluid, and selectively controlled valve means connecting the source to the pump means for supplying mixture of said fluid and the liquid to the heat transfer tube, the selectively controlled valve means including solenoid devices for respectively blocking flow of the cleaning fluid and conducting flow of the liquid in the outlet means in bypass relation to the heat transfer conduit, programmed means for energizing said solenoid devices in accordance with different operational stages, pulse-generatIng means connected to the programmed means for sequentially changing the operational stages, and indicator means connected to said programmed means for identifying the operational stages.

10. A cleaning apparatus, comprising an insulated tank containing a body of a first liquid, a heat transfer conduit mounted within the tank in heat-conductive relation to said first liquid and having an inlet and outlet means, pump means for supplying a second liquid to the heat transfer conduit at said inlet, a source of cleaning fluid, selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and said second liquid to the heat transfer conduit, and heating means mounted within the tank for imparting heat to said heat transfer conduit, said heating means including fuel burner means, a plurality of fuel supply tubes connected to the burner means, temperature-controlling valve means controlling flow of fuel through at least one of the supply tubes, and thermostatic sensing means mounted by the tank within the heat-storing liquid for operating the temperature-controlling valve means.

11. The apparatus of claim 10 having bypass means for selectively conducting said second liquid directly from said pump means to said outlet means.

12. In a cleaning apparatus having a tank containing a body of heat-storing fluid at a predetermined temperature, a heat exchange tube in the tank in heat-conductive relation to the heat-storing fluid, with an inlet and an outlet, pump means for supplying liquid to said tube at an inlet temperature substantially lower than said predetermined temperature, fuel burner means in said tank, a plurality of fuel supply tubes connected to the burner means, temperature-controlling valve means controlling flow of fuel through at least one of the supply tubes, thermostatic sensing means mounted by the tank within the heat-storing liquid for operating the temperature-controlling valve means, a source of cleaning fluid, and selectively controlled valve means connecting said source to said pump means for supplying a mixture of said fluid and said liquid to said tube.

13. A cleaning apparatus, comprising a tank containing a body of water, a coiled tube mounted within the tank in heat-conductive relation to the water, outlet means for discharging liquid from said coiled tube at a predetermined temperature and pressure, pump means for supplying liquid to said coiled tube at an inlet temperature substantially lower than said predetermined temperature, heating means within the tank and disposed inwardly of the coiled tube, said heating means including a coiled heating conduit through which a heating fluid is circulated, and bypass means for selectively conducting the liquid supplied by the pump means at said inlet temperature directly to the outlet means while preventing flow through said coiled tube.

14. A cleaning apparatus, comprising a tank containing a body of water, a coiled tube mounted within the tank in heat-conductive relation to the water, outlet means for discharging liquid from said coiled tube at a predetermined temperature and pressure, pump means for supplying liquid to said coiled tube at an inlet temperature substantially lower than said predetermined temperature, heating means within the tank and disposed inwardly of the coiled tube, said heating means including a coiled heating conduit through which a heating fluid is circulated, a source of cleaning fluid, and selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid to said coiled tube.

15. A cleaning apparatus, comprising an insulated tank containing a body of heat-storing fluid, a coiled tube mounted within the tank in heat-conductive relation to the heat-storing fluid, outlet means mounted on the taNk and connected directly to said coiled tube for discharging liquid at a predetermined temperature and pressure, pump means for supplying liquid to said coiled tube at an inlet temperature substantially lower than said predetermined temperature, heating means mounted within the tank and disposed inwardly of the coiled tube, and further including a plurality of heating conduits conducting flue gas from the heating means horizontally through the tank, and blower means for inducing flow of said flue gas through the heating conduits.

16. A cleaning apparatus, comprising a tank containing a body of heat-storing fluid, a heat transfer conduit mounted within the tank in heat-conductive relation to the heat-storing fluid and having outlet means for discharging liquid at a predetermined temperature and pressure, pump means for supplying liquid to the heat transfer conduit at an inlet temperature substantially lower than said predetermined temperature, a source of cleaning fluid, and selectively controlled valve means connecting the source to the pump means for supplying a mixture of said fluid and the liquid to the heat transfer tube, said selectively controlled valve means including solenoid devices for respectively blocking flow of the cleaning fluid and conducting flow of the liquid in the outlet means in bypass relation to the heat transfer conduit, programmed means for energizing said solenoid devices in accordance with different operational stages, pulse-generating means connected to the programmed means for sequentially changing the operational stages, and indicator means connected to said programmed means for identifying the operational stages.