US1790578A

US1790578A - Coolina system for marine and other engines

Info

Publication number: US1790578A
Authority: US
Publication date: 1931-01-27
Anticipated expiration: 1948-01-27

Description

coomne swsms FOR MARINE AND 0mm ENGINES 4 Sheets-She et 1 Filed May 25. 1928 INVEN TOR.

A TTORNEW Jan. 27, 1931. c. R. FOUTZ COOLING SYSTEM FOR MARINE AND OTHER ENGINES 4 Sheets-Sheet 2 INVENTOR.

ai/r/zu/z, v BY g 2 ATTORNEY)? Filed May 25. 1928 n Q M W MM fl wm Jan. 27, 1931. c. R. FOUTZ COOLING SYSTEM FOR MARINE AND OTHER ENGINES 4 Sheets-Sheet 3 Filed May 25. 1928' Ill-Iv INVENTOR.

ATTORNEY 8.

lmh

Patented Jan. 27,1931

; PATENT OFFICE CLINTON ROOT FOUTZ, OF BALTIMORE, MARYLAND cooLINe sysr am non; MARINE AND o'rnnn ENGINES Application filed May 25, 1928, Serial No. 280,617, and in Great Britain May 1, 1928.

This invention relates tointernal. combustion engines and has special reference to a cooling system for internal combustionengines.

In the conventional systems wherein the cylinders of the engine are water jacketed and kept from becoming too intensely heated by the circulation of water through the. water jacket, the jacket being vented to permit the 10 escape of steam it generated, many objections exist. It is well known that, within proper limits, the greater the temperature of the cylinders the more efficient is the operation of an internal combustion engine. 0 en,

or vented, water cooled systems are there ore objectionable because they keep the cylinder temperature too low when operating as they are intended and permit too great a temperature upon generation of steam. Moreover, it

is found that at so low a temperatre as'203 degrees Fahrenheit (usually much lower) the fluid being circulated becomes uncontrollable by the circulating pump thus making a. continuation of operation of the engine under such load as will raise the temperature to 203 degrees Fahrenheit impossible.

- The conventional evaporative or steam cooling does, it is true, afford an appreciable increase in economy of fuel and a more flexible motor for automotive work because of increase in jacket temperatures to handle 200.

degrees Fahrenheit. The weakness of this system is, however, in its limitation; for it can be shown that atmospheric air is always present and in combination with the steam, produced at 203 degrees and even lower, will prevent the water from making contact with the hottest part of the cylinder head, walls and combustion chamber because the boiling produces insulation of the walls from the liquid by a steam and air film. Indeed at this point spheroidal state of Water is reached and the limitation of the system has been reached for cooling except by metallic conductivity of the cylinder walls.

With my invention the action of the cooling medium just described is entirely changed. Liquid contact with the hottest' part of the cylinder is maintained up to any desired temperature, even to 450 degrees Fahrenheit or more. The cooling fluid is,

under perfect control and its velocity, and

consequently the volume passing through the jacket in a given time, is increased automatically when additional cooling is required and decreasedwhen the normal requirements are decreased. This is the result sought by the use of my improved hermetically sealed cooling system. q

From the above it will be apparent that the vapor pressure on the surface of the liquid acts to maintain the continuity of the column of water between the radiator outlet and the pump and thus insure that the cooling medium is-deliyered to the pump in mass flow without interruption, the degree of pressure at the pump suction depending upon the vapor pressure. In the absence of vapor pres- .sure, the water is fed to the pump by the hydrostatic head and where the heat-bf the water at the pump inlet tends to the creation of vapor, and cavitation of the pump takes place, the heat generated by the action of the pump and the suction effect of the pump necessary to draw in the water rapidly creates a steam or vapor condition which eventually breaks down the Water column and by the very reason of its production, creates a pressure which acts against the hydrostatic head of the water in the radiator and further tends to prevent the water, except in a very small stream, from reaching the pump.- This condition increases for the pump is deliver- I ing less and less water to the engine jackets and there is a continually increased heat-imparted to the cooling medium. Finally the cavitation effect is such that the pump is receiving nojwater and the system as a cooling system has broken down. The vapor pressure hereinabovereferred to, however, in-

creases with the increased heat of the medium, thereby supplements the hydrostatic head of the water leading to the'pump and delivers the water to the pump at a pressure which increases with the increased heat'of the cooling medium. Therefore, when the steam or vapor and thus quickly break down the water column leading to the pump, the vapor pressure in the improved system overcomes this tendency by adding to the hydrostatic head a pressure on the water column leading to the pump which maintains its integrity and insures the delivery of the water in a full mass volume and compels the pump to continually pump water to its full capaclty. The vapor pressure then, by maintaining this mass volume delivery tothe pump and a closed system. It is of courseiunderstood that a pump, no matter how great its capacity, is capable of discharging more water than it can receive through its suction inlet. Thus,

"under full inlet to the pump, the increased flow thereto will be proportional to the increased pressure on the medium delivered to the pump but where the pump inlet is throttled, the increased flow to the pump .will not necessarily be proportional to the increased pressure.

If the vapor or gas pressure can be varied, it follows as a matter of course that theflow will be correspondingly varied, such. flow being retarded where the vapor or gas pressure is less than atmospheric pressure and increased if the vapor or gas pressure is greater than atmospheric pressure. With the present construction, the pressure at the outlet from the source of supply is the suction draw of the pump plus the hydrostatic head plus the vapor or gaspressure on the surface. l/Vith a constant speed of pump, the water is forced into the container, the air expanding under heat creating an additional pressure, but owing to the designedlylarge pump capacity is unable to affect the acket pressure. This additional pressure, therefore, acts downwardly upon the surface of the downwardly flowing water, increasing the hydrostatic headto thereby increase the mass of water flowing to the pump. Thus, the volume and velocity are indirectly controlled by the vapor pressure and are not governed entirely by the effective pressure of the engine for the prevention of, water oil emulsion formationon the cylinder walls, thereby decreasing piston friction and crank case dilution.

It may be mentioned that in effecting this object the ordinary gasoline engines are operated at'276 degrees Fahrenheit with perfect control while the Deisel engines are 0perated at-400 degrees Fahrenheit or more under vapor pressure of 200 pounds per square inch or more.

Among the other important objects of my invention are the provision of a hermetically sealed cooling system for internalcombustion engines so arranged and constructed that the cooling may be effected with freshwater or volatile fluids, without loss by evaporation, and at engine Water jacket temperatures above the atmospheric boiling points of suchfluids; to provide an improved internal combustion engine cooling system so arranged and constructed as to increase the thermic efficiency of the engine by greatly increasing,

above the usual point, the external temper-- ature of the cylinder walls and the temperature of the combustion space, thereby decreasing heat losses by transference to the cooling medium, such losses being known to be, at low temperatures, directly proportional to the difference between the temperature in such combustion space and the fluid circulating in the water packet; to provide an improved cooling system of the class de scribed in which cooling is effected with fluids above their atmospheric boiling points to any predetermined and desired temperature, meanwhile maintaining such fluids in a liquid condition in contact with the walls of the cylinder and combustion space; to provide an improved system of the class described wherein water, alcohol or other volatile liquids are pumped and circulated through the engine Waterjacket in liquid state while at temperatures. greatly above their atmospheric boiling points; to provide effective cooling of the hot cylinder walls and combustion spaces directly proportional to the specific heat of the liquid circulated under all conditions of temperature; to provide an improved cooling system whereby a large portion of the heat heretofore lost to the cooling fluids and exhaust may be converted into mechanical power for use for propulsions by improved and-novel means;

and to establish and provide anautomatic self-regulating cooling system which will maintain the engine water jackets at constant temperatures during operation regardless of the load on such engine.

With the above and other objects in view as will be hereinafter apparent, the invention consists in general of certain novel details of construction and combinations of parts hereinafter fully described, illustrated in the accompanying drawings andspecifically claimed. i

In the accompanyin drawings like characters of reference indicatelike parts in the several views, and:

Figure 1 is a side elevation, partly in sect1on, showing a marine motor of internal combustion type installed in a vessel with my invention applied thereto.

Figure 2 is a rear elevation thereof, partly in section.

Figure 3 is a plan view thereof.

Figure 4 is a vertical section of an automatic hydrostatic fluid" control valve used herewith.

Figure 5 is a vertical section of a certain deaeration fluid check valve used herewith.

. In the embodiment of my invention herein disclosed I have illustrated the same as applied to a marine engine but it is to be understood that the invention is equally applicable to any other type of internal combustion engine. In this embodiment theengine is indicated in general at 10 and is shown as mounted within the hull of a ship S. This engine is provided with the usual water jacket for the cylinders and for the purpose of positively circulating the water there is provided a circulating pump 11 which has its discharge 12 connected through a manifold 13 to the,

water intakes of the engine cylinders. Leading from the cutlets or exhaust of these water jackets are the branches 'of a manifold 14 which is connected by a pipe 15 to the upper part of a vertically disposed cylindrical tank 16 closed at its top and constituting what is preferably termed an expansion tank. In operation liquid fills the tank substantially to the water line 17 so that the upper part ofthe tank 16 forms a vapor chamber.v It will be understood that the pump 11 may be driven from the engine by a suitable gearing 18 or may be driven in any other desired manner- On the upper endof the tank 16 there is provided an outwardly opening relief valve 19 which may be of any preferred. type, open-i ing to allow air or vapor to pass out through a discharge pipe 20 to any suitable place but closing agamst the-admission of any air through the tank 16. From the upper part of the tank 16 is a pipe 21 provided with a stop valve 22 which leads to a condenser coil 23 contained in a vertical tank 24. The pipe 21 connects to the upper end of the condenser coil and from the lower end of said coil a pipe 25 having an outwardly opening check valve 26 leads to a suction pump or jet device, which may be of the ordinary .Venturi type, indicated at 27 in the intake 28 of the pump 11. The pump intake is extended by means of a pipe 29 to a-coolingcoi'l 30 of any suitable type, the coil being here shown as consisting of a length of ipe extending fore.

and aft alongside of the eel of the ship although it is to be understood that this arrangement is but typical of any cooling device cooled in any desired manner. The re- 'so that the circulated liquid from this tank 7 is drawn by the pump through the cooler 30, being supplied to the pump through the pipe 29 .and the intake 28 thus creating suction at the suction device 27. 1

The tank 24 is supplied with cold water by means'of a pipe 32 leading from the outboard of the ship or from any other convenient source of supply, to the upper part of said tank and from the lower part of the tank a pipe 33 leads to the suction or intake side of the pump 34 preferably mounted on the same shaft as the pump 11 though it is obvious that either or both of these overboard from this manifold, if desired,

through the pipe 37. In some cases, as those of large Deisel engines, the engine exhaust manifold will be cooled by the same cooling fluid as-that used for the cylinders and combustion spaces. In such cases the proper pipe lead will bemade from the pump 11 to the exhaust manifold jacket 36 and then the discharge pipe 37 will be led directly into the pipe 15 close to where it enters the tank 16. Under such cases the pipe 35 will be replaced by a suitable pipe leading directly overboard.

At 38 is indicated 1n general a certain hydrostatic fluid control valve which will be presently described in detail and this valve is connected by a pipe 39 with the intake 29 at a point more remote from the pump 11 than the suction device 27. Also the valve 38 is connected by a pipe 40 with a second water cooler 41- which I preferably term a super-cooler and which may be arranged around the keel similar to thecoil 30 or, like it, in any preferred manner to cool the liquid passing therethrough. The remaining end of this super-cooler is connected by a pipe 42 a with a special inlet valve 43 which is preferably termed a deaeration fluid check valve or aero-absence valve and a construction of which will be more specifically described hereinafter, this construction being shown in Figure 5.

At 44 is a reserve ply of the cooling liquid and this tank is connected by a pipe 45 with a valve 46 within the tank 16, this valve being controlled by a float 47 so that, so long as the water level 17 is maintained at the proper point, thevalve 46 will remain closed, opening only when this water level drops below the desired height. Moreover, the upper part of the tank 44 is connected by'a pipe 48 with the upper part of the tank 16, the pipe 48 entering the tank and being extended downward'as at 49 to a point normally slightly below. the water tank for the reserve sup-.1

level 17 so that when the water level drops the pipe 48 is placed in communication with the upper part of the tank 16 and the pressure within the tanks 16 and 44 above the liquid contained therein is thereby equalized so that there is no resistance to flow of liquid from the tank 44 to the tank 16 when the valve 46 is'openedI This tank 44 is provided with a suitable filler cap 50 so arranged and packed that it may be used to hermetically seal the tank 44 when screwed home. The described arrangement is but typical, it being contemplated that any suitable means may be utilized formaintaining the waterlevel or re filling.

As a means of utilizing the vapor pressure at certain stages in the operation of the device,and which becomes available at those stages, I may provide a steam turbine 51 having a supply pipe 52 connected to the pipe 21 and thus to the upper part of the tank 16, the supply pipe being provided with a throttle 53. The exhaust from this turbine is led back by a pipe 54 into the condenser coil 23. The power derived from the turbine may be utilized in any desired manner, as for instance by coupling theturbine shaft at 55 to a dynamo 56..

At 57 is shown a suitable dialor other regulating valve or cock which is placed in the line 29 more remote from the pum 11 than the connection of the valve 38. onnected to the top of the tank 16 is a vacuum gauge 58, a pressure gauge 59 graduated in pounds per square inch and a pressure gauge 60 which is graduated in degrees of temperature' so that the Vapor pressure of pure deaer'ated water may be read at the corresponding pressures on the gauge 59. Moreover, there is connected to the line 25 a gauge 61 which is a compound gauge graduated to show the differential existing in the condenser when pressure exists in the upper part of-the tank 16 and also to show dynamic suction or lift in inches of mercury when subatmospheric conditions exist, that is when direct static vacuum exists in the upper part of the tank 16. A thermometer 61' is also connected to the manifold 14 for showing the temperature of theliquid in contact with the cylinder walls.

The fluid control valve 38 has a body 62 of the usual shape common to stop or throttle valves, this body having a seat 63. The upper part of the body is, however, provided with an extended flange portion 64 threaded on its exterior, this flange portion being dished to provide a recess or chamber 65. Centrally of the body is the usual guide opening 66 for I the valve stem 67 carrying on its lower end a valve proper 68 which, when closed, engages the seat 63. It is to be understood that while in the form shown in the drawings this valve is a cone valve yet other types such as those employing fiat rubber seats may be substituted without change in the invention. A bleeder opening 69 leads from the inlet sideof the valve body to the chamber 65. Screwed onto the threaded flange 64 is a Valve bonnet 70 having a centrally disposed cylindrical por tion and a wider lower end so that a diaphragm 71 is held between the upper edge of the flange 64 and the valve bonnet, the bonnet being recessed at. 72130 provide a chamber above this diaphragm. The stem 67 has an upwardly extending threaded portion 7 3 which passes through the center of the diaphragm and on this threaded portion is screwed a disc 74 which thus clamps the diaphragm between the valve stem and said disc so that as the disc moves up and down at its center the valve correspondingly opens and be regulated so that the valve will only open I when pressure in the chamber 65 resulting from pressure on the inlet side of the Valve being transmitted through the opening 69,

becomes sufiicient to raise the valve against a the action of the springs. Moreover, the valve will only lift off its seat to just such extent that the fluid passing through the valve will equalize the pressure in the chamber 65 with the pressure produced by the compression of the spring 77. The valve thus, when set for a given pressure on the outlet side automatically maintains that pressure.

The valve 43 is also of special construction.

This valve has a body 80 of the ordinary form, the body having an upwardly extending neck 81 closed by a cap or bonnet 82. Also the body has a downwardly extending neck 83 having a 'segmentospherical flange 84 projecting from its lower end and terminating outwardly in a fiat peripheral flange 85. This portion of the body forms the top of the diaphragm housing the lower portion of which has its central part 86 shaped similarly to the part '84 and is provided with a flange 87, corresponding to the flange 85 so that the two parts of the housing may be held together by bolts 88. In the valve body 80 is the usual seat 89 whereon seats a'valve propel 90 and in the partition between the inlet and outlet ends of this valve is a bleeder opening 91 which thus opens beneath the valve 90. The valve 90 is provided with a stem92 having a spider 93 on its up-f per end whichfits within the neck 81 to guide the valve. Similarly the lower part of the stem 18 provided with a fluid packed piston drical bore of the neck 83. The diaphragm consists of two yieldable plates having segmental spherical central portions 95 and flat peripheral portions .96 secured together by rivets or bolts 97, the edges ofthese plates being held between suitably s igced portions of the peripheral flanges 85. y this means the diaphragm constitutes an ellipsoidal cell. In operation this diaphragm is'partly filled with water and for the proportions of this invention it is preferred that the water should be 60 degrees Fahrenheit when it is placed in the diaphragm and that the air shall be at 760 millimeters atmospheric pressure as measured by a mercury column. Under any conditions there will always be provided just suiiicient water to insure a saturated mixture of air and water vapor at whatever predetermined maximum temperature and the above barometric pressure the valve will be in neutral position, neither expanded nor contracted. If the temperature is lowered the aqueous vapor pressure in the cell is de- "reased, as is also the volume of air, and the cell will contract. Likewise, increasing the temperature causes increase of aqueous vapor and air pressure in the cell so that the cell will expand. Centrally o'f the diaphragm housing 86 is a boss 97 and threaded through this boss is an adjusting screw 98 provided with a nut lock 99. The inner end of this screw engages a pressure thrust block 100 secured centrally to the lower side of the cell by means of a suitable nut 101. Un top of the cell is mounted a diaphragm thrust block 102 which is secured to the cell by a suitable bolt 103. This thrust block 102 is positioned so that normally it is spaced a few thousandths of an inch below the lower surface of the piston head 94. This piston head is preferably made hollow and provided with a bleeder opening 104 so that pressure above and below the head is equalized, it being observed that the bleeder 91 also equalizes pressure above and below the valve 90. It is intended that the cell shall expand upwardly at all times and to this end the lower side of the cell is supported on annular ribs or supports 105, the central portion being obviously supported on the screw 98. In order to understand the operation of the ,remainder of the device it is advisable here to consider the operation of this particular valve as much depends thereon and it will be noted that the upper diaphragm casing 84 is provided with suitable openings 106 so that the contents of the tank in which the valve is placed may.

flow in and surround the cell.-

For the purpose of understanding the operation of this valve it may be mentioned that at the start of the operation of the cooling system the tank 16 will be filled to the water line 17 with water containing a certain amount of air in solution while above the water the tank will be filled with air which naturally contains a certain amount of aqueous vapor. Now, since the water in the tank surrounds the cell the temperature of the water in the cell will be the same as the temperature of the water in the tank and, assuming that when the tank is filled and closed the atmospheric pressure in the upper part is 760 millimeters of mercury, the vapor tension in the upper part of the cell will be identical with the vapor tension in the upper part of the tank thus a state of equilibrium exists and no movement of the valve 90 will take place. Under operation of the system the water from the tank- 16 is circulated through the water jackets of the engine and accordingly becomes hot so that the vapor pressure above the water in the tank increases. As an example we may say that the valve 19 had been set to open at 210 pounds per square inch. When, therefore, the vapor pressure in the upper part of the tank equals 210 pounds the valve 19 will open and the air will escape during the blow down from the tank. Now, remembering that when the water has been heated to bring the pressure above the water line to 210 pounds the water in the cell has also been heated and the cell pressure has likewise been raised to 210 pounds. Upon'opening of the valve 19 air will escape during the blow down which thus decreases the pressure above the water line while at the same time the cell, being hermetically sealed does not have its pressure decreased and will expand upwardly so that the valve 90 will be forced off its seat, this amount of water in the form of Va or, repetition of this operation will finally ree all of the water in thecirculating system from air gas until eventually the tank 16 will be filled to the water line with water and above the water line withaqueous vapor free from air, it being remembered that the air in solution in the water is. given 011 at a temperature much below its boiling point. However, air will always remain in the cell so that no matter what the temperature of the water in the tank 16 may be or what may be the variation in the pressure it will always be less than that within the cell thus the valve will be normaltoo ly held off its seat until by accidental leak- .Within the cell. However,- as will be presently understood the water line underthese circumstances will not drop below its northat the tank 16 contains air and aqueous vapor in its upper part as previously described then the valve 43 will be closed. If the engine be now started the pumps 11 and 34 also start to operate or may be started if separately driven, the pump 34 when thus started operates to circulate cold water through the condenser 24 around the coil 23.

. At the same time the pump 11 forces water through the engine water jackets and their connections into the upper part of the tank 16. The water which is thus forced through the water jackets is drawn through the pipe 29 from the cooler 30 and as it passes the suction device 27 exerts a powerful suction on the pipe 25. Just at the start the water level 17 will drop slightly but due to the suction exerted on the pipe 27 the vapor above the water level with a certain amount of air will be drawn through the pipe 21 and coil 23, the vapor being there condensed. Thus an emulsion of air and water will first be circulated through the water jacket to the engine and since this emulsion of air and water has a specific heat much less than that of water itself the engine will quickly heat up so that the .water in the tank 16 will quickly become hot and the pressure in such tank will increase. Consequently, when the pressure'has reached the desired point, the valve 19 will open and a certain amount of air and vapor will pass out, it bein remembered that the remainder will a ways be drawn through the condenser and be condensed, the water escaping being replaced in the tank 44 as previously described. This operation will continue automatically until the circulating water has been freed from air.

As before noted when this takes place the valve 43 will remain constantly open and the valve 46 constantly closed. Now, since the valve 19 is set to blow off at such pressure as corresponds with the desired temperature to be maintained in the cylinder jackets and since the condenser will condense all of the vapor passing through it, its size being proportioned' to eflect this object, there will cease to be an emulsion of air and water circulating through the water jackets but the circulating medium will then be water which,

with its relatively high specific heat, will prevent the cylinder walls and combustion chamber of the engine from rising above the desired temperature. The cylinder walls and combustion chamber valre thus permitted quickly to attain the desired temperature and t en maintained at that temperature.

The valve 57, which as stated is a suitable dial controlling valve, is placed in the main suction line of the pump 11 and the cooling fluid circulates through it in normal engine I operation. By reference to the dial of the valve, such valve canbe accurately adjusted to throttle the mass flow to the pump, so that only the approximately necessary volume of water will be pumped per minute to maintain the engine jacket water, say, at 380 Fahrenheit. At 380 Fahrenheit, the aqueous vapor pressure is 196 pounds per square inch. If the temperature in the engine jacket under any condition of operation starts "to increase and rises, say, to 382 Fahrenheit, the steam pressure in the system will increase to substantially 200 pounds per square inch. Under these conditions, the

valve 38, which has been set forthis predeter-' mined pressure, will open and admit into the pump suction, in advance of the valve 57,-

a stream of cold water through the pipe 40 y from the'super-cooler 41, of a volume equal to the pumps unrestricted suction capaclty. This volume of cold water, entering the enginejacket, uickly reduces the temperature therein and t e consequent drop of pressure when the temperature reaches a point slightly below 382 Fahrenheit, say 377 Fahrenheit, at which the pressure of the aqueous vapor 1s approximately 190 pounds per square inch, will permit the valve 38, to close. Thus, cooling from the increased mass flow of cool water'is automatically cut ofi. The cooling medium is thus under perfect control, the pump being by design of a capacity and dlscharge so greatly in excess of the normal operating conditions that its discharge s not effected by the back pressure in the jacket. The mass flow is automatically controlled by the volume of cooling water admitted to the suction and is dependent upon and the volume entering the engine jacket is controlled according to the increase or decrease in the engine temperature.

Y Therefore, as the valve 19 is-set for a definite pressure corresponding to a definite temperature of aqueous vapor, this valve cannot again open because the valve 38, which is set for opening at a'pressure less than that of the valve 19, will, as stated, permit an entrance of cool water into the system to reduce the temperature of the cooling medium and thereby the pressure of the aqueous vapor, before such pressure reaches the point at which valve 19 opens. Therefore, when working with the water deaerated, the predetermined working temperature and pressure cannot be exceeded nor can valve 19 again 0 en, for without air in the systein to close t e aeroabsence valve43, suchvalve 43 will always remain open and as the temperature will be al ways controlled and reduced when'reaching the predetermined limit by the injection of' tion engines, a circulatory system for the cooling fluid permanently closed against the admission of air, means'for relieving the system of the initially contained air under a predetermined pressure of such contained air, and means for continually redelivering the contained air to thecooling medium up to the point of said predetermined pressure. 3

2. In a cooling system for internal combustion engines, a circulatory system for the cooling fluid permanently closed against the admission of air, means for relieving the system of the initially contained air under a predetermined pressure vof such contained air, and means for continually redelivering the contained air to the cooling medium up to the point of said predetermined pressure, said latter means being governed by the circulation of the cooling medium.

3. A water cooling system for internal combustion engines, comprising a circulatory system for the cooling medium including a pump and a reservoir providing a vapor chamber above the circulating medium, a circulation controlling valve governing an additional communication to the pump and arranged in the reservoir, said valvebeing responsive to the pressure variations governed by the heat of the water in the reservoir.

4. A water cooling system for internal combustion engines, comprising a circulatory system 'for the cooling medium'including a pump and a reservoir providing a vapor chamber above the circulating medium, a circulation controlling valve governing an additional communication to the pump and arranged in the reservoir, said valve being responsive to the pressure variations governerned by the heat of the water in the reservoir, and means for cooling the circulating medium.

5. In a water cooling system for internal combustion engines, a circulating system for thecooling fluid including a pump and a reservoir providing a vapor chamber above the level of the cooling medium within'the reservoir, and means controlled by the heat conditions of the cooling medium of the reservoir for relieving the reservoir under predetermined heat conditions of a portion of the heated cooling medium.

6. In a water cooling system for internal combustion engines, a' circulating system for the cooling fluid including a pump and a reservoir providing a vapor chamber abovethe level of the cooling medium within the reservoir, means controlled, by the heat conditions of the cooling medium. of the reservoir medium from the reservoir to the suction-side for relievingthe reservoir under predetermined heat conditions of a portion of the heated coolingmedium, and means for delivering such portion of the heated coollng of the pump.

7. In a Water cooling 'system-forinternal combustion engines, a circulating system for the cooling fluid including a pump and a reservoir providing a vapor chamber above the level of the cooling medium within the reservoir, means controlled by the heat conditions of the cooling medium of the reservoir for relieving the reservoir under predetermined heat conditions of a portiorr of the heated cooling medium, means for delivering,

nchportion of the heated cooling medium from the reservoir to the suction side of the pump, and a hydrostatic valve for controlling such delivery.

8. In a water cooling system for internal combustion engines, a circulating systemfor the cooling fluid including a pump and a reservoir providing a vapor chamber abpve the level of the coolin medium within the reservoir, means contro led by the heat conditions of the cooling medium of the reservoir for relieving the reservoir underpredeter mined heat conditions ofa portion of the heated cooling medium, means for delivering such portion of the heated cooling medium from the reservoir to the suction side of the pump, and means for cooling such portion of the cooling'mediumpribr to its delivery to the pump. 9. A cooling system for internal combustion engines, mcluding a circulatory system for the cooling medium having a pump and a reservoir, with the latter providing a vapor space above the level of the cooling medium,

- therein, a second circulatory path between the reservoir andsuction side of the pump, a valve normally closing said second circulatory path, and means for controlling the valve, said means being responsive to the heat conditions of the cooling medium in the reservo1r.

' 10. A cooling system for internal combustion engines, including a circulatory system for the cooling medium having a pump and a reservoir, with the latter providing a vapor space above the level of the cooling medium therein, a second circulatory path between the reservoir and suction side of the pump, a cooling means for said second circulatory path, a valve normally closing said second circulatory path, and means for controlling the valve, said means being responsive to the heat conditions of the cooling-medium in the reservoir.

11. A cooling system for internal combustion engines, including a circulatory system for the cooling medium having a pump and a reservoir, with the latter providing a vapor space above the level of the cooling medium ice I therein, a second circulatory path between the reservoir and suction side of the pump, a cooling means for said second circulatory path, a valve normally closing said second circulatory path, means for controlling the valve, said means being responsive to the heat conditions of the cooling medium in the reservoir, and means inv said second circulatory path controlled by the pressure of the vapor in said vapor chamber for governing the quantity of cooling medium delivered to the suction side ofthe pump through such second circulatory path. ,c

12. A cooling system for'internal combustion engines, including a circulatory system for the cooling medium having a pump and a reservoir, with the latter providing a vapor space above the level of the cooling medium therein, a second circulatory path between the reservoir and suction side of the pump, a cooling meansv for said second circulatory path, a valve normally closing said second circulatory path, means for controlling the valve,

said means being responsive to the heat conditions of the cooling medium in the reservoir, means in said second circulatory path controlled by the pressure of the vapor in said vapor chamber for governing the quantity of cooling medium delivered to the suction side .of the pump through such second circulatory path, and means controlled by the level of cooling fluid in the reservoir for governing admission of additional cooling fluid to the medium in the reservoir.

13. A cooling system for internal combustion engines, including a circulatory system permanently closed against the admission of air, means to circulate the contained air from the cooling medium, means to permit systematic ejection of the contained air at predetermined temperatures of operation, and means to thereafter automatically maintain thesystem free from air.

14. In a cooling system for internal combustion engines, a circulatory system for the cooling fluid permanently closed against the admission of air, means for relieving the system of initiallycontained air under a predetermined pressure of such contain-ed air, and,

means for automatically introducing intovthe system an additional volume of cooling medium when the temperature of the cooling system reaches a predetermined point. v

15. In a cooling system for internal eombustion engines, a circulatory system for the cooling fluid permanently closed against the admission'of. air, means set for operation at a predetermined pressure for-relieving the system of the initially contained air, and -means set for operation at a somewhat lower pressure for admitting into the system an additional supply of cooling medium.

16, In a water cooling system for internal combustion engines, a circulatory system for the cooling fluid including a pump, a reservoir providing a vapor chamber above the level of the cooling medium within the reservoir, a relief valve for the vapor chamber set to open at a predetermined pressure, a hydrostatic valve for' admitting an additional volume of cooling 'medium to the pump, said hydrostatic valve beingset to open at a pressure less than the setting of the relief valve,

and means controlled by the heat conditions