US2176331A - Circulatory cooling system for internal combustion engines - Google Patents

Circulatory cooling system for internal combustion engines Download PDF

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US2176331A
US2176331A US62788A US6278836A US2176331A US 2176331 A US2176331 A US 2176331A US 62788 A US62788 A US 62788A US 6278836 A US6278836 A US 6278836A US 2176331 A US2176331 A US 2176331A
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radiator
liquid
bypass
engine
valve
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US62788A
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Harold B Drapeau
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Dole Valve Co
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Dole Valve Co
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01PCOOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P7/00Controlling of coolant flow
    • F01P7/14Controlling of coolant flow the coolant being liquid
    • F01P7/16Controlling of coolant flow the coolant being liquid by thermostatic control

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  • This invention relates to circulatory cooling systems for internal combustion engines and has for its object to provide a new and improved system of this description.
  • the invention has as a further object to provide a circulatory cooling system for internal combustion engines with a thermostatic control arranged so that the engine cannot become overheated if the thermostat remains closed.
  • the invention has as a further object to provide such a system wherein without endangering the engine because of overheating, the liquid in the system can be kept at a sufllciently high temperature to be utilized for heating the interior of the automobile, regardless of the external temperature and the high speed of the automobile.
  • the invention has as a further object to provide such a system having a controlled bypass and having the main. circulatory system through the radiator open at all times.
  • the invention has as a further object to provide a system of this description having a. bypass, having a valve thermostatically contrqlled by a reversely acting thermostat which closes the valve when the thermostat is heated, the main circulatory system being free from any thermostatic controlling device.
  • the invention has other objects which are more particularly pointed out in the accompanying description.
  • Fig. 1 is a view showing an internal combustion engine provided with one form of circulatory cooling embodying the invention
  • Fig. 2 is a view showing a modified construction
  • Fig. 3 is a view showing a modified construction of the lower end of the bypass.
  • a conduit 3 is connected with the outlet 2 of the water jacket and leads to the radiator
  • a conduit 5 connects the radiator 4 with the water jacket of the cyline der blockof the engine, thus forming a circulatory system from thewa'ter jacket to the engine through the radiator.
  • a pump is located some. where in this system. As herein shown, there is provided a pump 6 which takes the liquid from the conduit. 5 and pumps it through the water 'jacketand/through. the system.
  • the main circulatory system is free from any thermostatic or other movable controlling device. Connected in (01.
  • this system is a bypass 1, which as herein shown connects the conduits 3 and 5.
  • a valve 8 Located inthe' bypass I is a valve 8.
  • This valve may be of any suitable construction andior the purposes of illustration is shown as a butterfly valve pivotally mounted at 9.
  • a thermostat I0 is connected with this valve and with a fixed part, the thermostat being a reversely acting thermostat which Opens the valve when cool or partially closes or closes the valve when hot.
  • Some means is provided for directing the liquid from the water jac at of the engine into the bypass. This means l depend upon the location of the bypass and the construction of the parts. In the construction illustrated in Fig.
  • the bypass is connected with the end of the conduit 3 nearest the engine and there is arranged a nozzle which directs the liquid from the water jacket into the bypass.
  • This nozzle may be of anysuitable form and is preferably of the Venturi type.
  • the discharge end ii of the nozzle H is smaller in cross sectional area than the portion of the pipe or conduit surrounding it, so as to leave a space l3 through which liquid may pass to the conduit 3 and the radiator i.
  • the discharge end of the nozzle is also preferably of substantially the same cross sectional area as the conduit 3.
  • the lower end of the conduit 3, the nozzle H and the upper end of the bypass are preferably formed of a single unitary construction, but it may be of any other construction.
  • I may arrange the lower end of the bypass I with a discharge endla which discharges the liquid toward the radiator, so that when the by-pass is in operation this liquid opposes the flow of the liquid from the bottom of the radiator.
  • This discharge end may be in the form of a nozzle and also of a Venturi nozzle.
  • Fig. 2 I have shown a modified construction where there is a pipe i4 connected with the engine water jacket and which is provided with a nozzle l5 connected with the conduit 3 leading to the radiator.
  • the by-pass i6 is provided with a portion H which projects into the lower end 30. of the conduit 3 and which is opposite the nozzle I5, there being a circular space It between the nozzle l5 and the end ll of the by-pass.
  • the lower end So of the conduit 3 surrounds the opposed ends of the nozzle and the by-pass.
  • the valve [9 Located in the by-pass is the valve [9 which is normally open when the cooling liquid is cool and which is actuated by the thermostat 28. which is a reversely acting thermostat.
  • the pump and other parts may be arranged in any desired manner.
  • leading from the bottom of the radiator I connects with the by-pass I6 and the conduit 2
  • the pump when in operation draws the liquid through the pipe I when the by-pass is open, a small portion being also drawn through the pipe 2 I.
  • the by-pass is partially closed more liquid is drawn through the conduit 2
  • Fig. i when the engine first starts up the liquid and thermostat it are cold and the valve 8 in the bypass is open.
  • the pump 8 being now in operation, directs the fluid from the water jacket through the opening 2 into the' nozzle ii and out at the end l2 of the nozzle into bypass I.
  • the cooling liquid passes through the bypass into the conduit 5 and back through the pump into the engine water jacket.
  • the liquid passing out of nozzle II is directed into the bypass instead of passing through the conduit 3 to the radiator, and thus the cooling liquid is short-circuited around the radiator.
  • the parts are preferably arranged so that a small amount of the cooling liquid will pass into the pipe 3 and through the radiator 1 when the valve 8 is fully open, so as to prevent stagnation of the liquid in the radiator.
  • the thermostat i 0 will be heated and will move the valve 8 towards its closed position.
  • the valve 8 When the valve 8 is partially closed the cross sectional area of the bypass at this point is reduced and part of the liquid passes through the conduit 3 ,into the radiator 4 and back to the water jacket of the engine.
  • the amount that the valve 8 is closed depends upon the conditions. In hot weather for example, the cooling fluid may reach such a temperature that the valve 8 will be entirely closed and then the cooling liquid will circulate through the main circulatory system, consisting of the water jacket of the engine, the conduit 3, radiator 4 and the return conduit 5. In cold weather the valve 8 may be only'partially closed so that a. portion of the cooling fluid passes continuously through the bypass so, that it will be heated a suillcient temperature to maintain the efli'ciency of the engine and to provide heat for the heaters forrheating the interior oi the automobile. 4
  • the cooling liquid inthe water jacket of the engine may be maintained at the proper temperature for maintaining the efll'ciency of the engine and for use in the heaters, regardless of the low outside temperature and when the engine is running at an exceedingly high speed.
  • the parts can be arranged so that this liquid may be maintained at the desired temperature -maximum efilciency and the temperature of the become injured.
  • the thermostat works prop- 19 erly,.then in cold weather and when the engine is running at very high speed, the cooling liquid is cooled to such a degree that the engine is not heated to suflicient temperature to secure its 1 liquid is too low to be effectively used for heating 6 purposes.
  • the radiator in the very coldest weather the radiator may be substantially out out of circuit except for the flow necessary to prevent stagnation of the liquid therein, and when the weather is not so exceedingly cold the radiator may be alternately cut in and out, and in warmer weather more or less of the radiator utilized as the conditions require, and all this is done automatically and with entire safety to the engine.
  • a circulatory cooling system for internal combustion engines provided with a water jacket and a radiator, comprising a continuously open main circulating circuit from the water jacket through the radiator for the cooling liquid, and through which a portion of the cooling liquid at all times passes when the engine is running, a bypass around the radiator, through which a portion of the cooling liquid passes when the engine is running,said water jacket having an outletin alignment with the inlet of said bypass.
  • a circulatory cooling system for internal combustion engines provided with a water jacket and a radiator, comprising a continuously open main circulating circuit from the water jacket through the radiator for the cooling liquid, and through which a portion of the cooling liquid at 7 all times passes when the engine is running. a bypass around the radiator. through which a portion of the cooling liquid poses when the engine is running, means for directing water from the water jacket of the engine directly into the inlet end of 76 the bypass and a thermostat located in the bypass intermediate its ends.
  • a circulatory cooling system for internal combustion engines provided with a water jacket and a radiator, comprising a continuously open main circulating circuit from the water jacket through the radiator for the cooling liquid, a bypass around the radiator, means for utilizing the energy of the cooling liquid for directing cooling liquid into said bypass, a valve insaid bypass, normally open when the cooling liquid is cool, a thermostat connected with said valve so as to open it, the thermostat actingto move the valve towardits closed position when the temperature of the cooling liquid rises above apredetermined point.
  • a circulatory cooling system for internal combustion engines provided with a water jacket and a radiator comprising a continuously open main circulating circuit from the water jacket through the radiator for the cooling liquid, a bypass extending from the upper part of the main circulatory circuit to the lower part thereof and provided with a nozzle directed toward the radiator, a valve in said bypass, normally open when the cooling liquid is coolga thermostat connected with said valve so as to operate it, the thermostat acting to move the valve towards its closed position when the'temperature of the cooling liquid rises above a predetermined point.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Temperature-Responsive Valves (AREA)

Description

Oct. 17, 1939.
H. B. DRAPEAU CIRCULATORY COOLING SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed Feb. 7, 1936 Invenzfor Patented Oct. 17,1939
PATENT IOFFICE CIRCULATORY COOLING SYSTEM FOR IN- TERNALCOMBUSTI ON ENGINES Harold B. Drapcau, Chicago, Ill., assignor to The Dole Valve Company, Chicago, Ill., acorporation of Illinois Application February 7, 1936, Serial No. 62,788
4 Claims.
This invention relates to circulatory cooling systems for internal combustion engines and has for its object to provide a new and improved system of this description.
The invention has as a further object to provide a circulatory cooling system for internal combustion engines with a thermostatic control arranged so that the engine cannot become overheated if the thermostat remains closed. The
invention has as a further object to provide such a system wherein without endangering the engine because of overheating, the liquid in the system can be kept at a sufllciently high temperature to be utilized for heating the interior of the automobile, regardless of the external temperature and the high speed of the automobile.
The invention has as a further object to provide such a system having a controlled bypass and having the main. circulatory system through the radiator open at all times. The invention has as a further object to provide a system of this description having a. bypass, having a valve thermostatically contrqlled by a reversely acting thermostat which closes the valve when the thermostat is heated, the main circulatory system being free from any thermostatic controlling device. The invention has other objects which are more particularly pointed out in the accompanying description.
Referring now to the drawing,
Fig. 1 is a view showing an internal combustion engine provided with one form of circulatory cooling embodying the invention;
Fig. 2 is a view showing a modified construction;
Fig. 3 is a view showing a modified construction of the lower end of the bypass.
Like numerals refer to like parts throughout the several figures.
Referring now to the drawing, I have illustrated a conventional form of internal combustion engine having the cylinder block I with the usual water jacket having anoutlet 2. A conduit 3 is connected with the outlet 2 of the water jacket and leads to the radiator A conduit 5 connects the radiator 4 with the water jacket of the cyline der blockof the engine, thus forming a circulatory system from thewa'ter jacket to the engine through the radiator. A pump is located some. where in this system. As herein shown, there is provided a pump 6 which takes the liquid from the conduit. 5 and pumps it through the water 'jacketand/through. the system. The main circulatory system is free from any thermostatic or other movable controlling device. Connected in (01. ice-17's) this system is a bypass 1, which as herein shown connects the conduits 3 and 5. Located inthe' bypass I is a valve 8. This valve may be of any suitable construction andior the purposes of illustration is shown as a butterfly valve pivotally mounted at 9. A thermostat I0 is connected with this valve and with a fixed part, the thermostat being a reversely acting thermostat which Opens the valve when cool or partially closes or closes the valve when hot. Some means is provided for directing the liquid from the water jac at of the engine into the bypass. This means l depend upon the location of the bypass and the construction of the parts. In the construction illustrated in Fig. 1, the bypass is connected with the end of the conduit 3 nearest the engine and there is arranged a nozzle which directs the liquid from the water jacket into the bypass. This nozzle may be of anysuitable form and is preferably of the Venturi type. The discharge end ii of the nozzle H is smaller in cross sectional area than the portion of the pipe or conduit surrounding it, so as to leave a space l3 through which liquid may pass to the conduit 3 and the radiator i. The discharge end of the nozzle is also preferably of substantially the same cross sectional area as the conduit 3. In the particular construction shown, the lower end of the conduit 3, the nozzle H and the upper end of the bypass are preferably formed of a single unitary construction, but it may be of any other construction.
Under certain conditions and for certain constructions, Imay arrange the lower end of the bypass I with a discharge endla which discharges the liquid toward the radiator, so that when the by-pass is in operation this liquid opposes the flow of the liquid from the bottom of the radiator. This discharge end may be in the form of a nozzle and also of a Venturi nozzle.
In Fig. 2 I have shown a modified construction where there is a pipe i4 connected with the engine water jacket and which is provided with a nozzle l5 connected with the conduit 3 leading to the radiator. The by-pass i6 is provided with a portion H which projects into the lower end 30. of the conduit 3 and which is opposite the nozzle I5, there being a circular space It between the nozzle l5 and the end ll of the by-pass. The lower end So of the conduit 3 surrounds the opposed ends of the nozzle and the by-pass. Located in the by-pass is the valve [9 which is normally open when the cooling liquid is cool and which is actuated by the thermostat 28. which is a reversely acting thermostat.
It is of course evident that the pump and other parts may be arranged in any desired manner. In this particular construction the conduit 2| leading from the bottom of the radiator I connects with the by-pass I6 and the conduit 2| and by-pass it are connected to the pump 22 by a pipe 23. The pump when in operation draws the liquid through the pipe I when the by-pass is open, a small portion being also drawn through the pipe 2 I. When the by-pass is partially closed more liquid is drawn through the conduit 2| and when the b'y-pass is completely closed all the liquid is drawn through the conduit 2| the liquid being discharged into the water jacket of'the engine.
I have described in detail a particular construction embodying the invention, but it is of course'evident that the partsmay be varied in ,many particulars without departing from the spirit of the invention asembodied in the claims hereto appended, and I therefore'do not limit myself to the particular construction shown.
The use and operation of my invention are as follows.
Referring now to Fig. i, when the engine first starts up the liquid and thermostat it are cold and the valve 8 in the bypass is open. The pump 8 being now in operation, directs the fluid from the water jacket through the opening 2 into the' nozzle ii and out at the end l2 of the nozzle into bypass I. The cooling liquid passes through the bypass into the conduit 5 and back through the pump into the engine water jacket. The liquid passing out of nozzle II is directed into the bypass instead of passing through the conduit 3 to the radiator, and thus the cooling liquid is short-circuited around the radiator. The
discharge of the liquid from the nozzle ll produces a reduced pressure around said nozzle in the space l3. The parts are preferably arranged so that a small amount of the cooling liquid will pass into the pipe 3 and through the radiator 1 when the valve 8 is fully open, so as to prevent stagnation of the liquid in the radiator.
As the liquid in the water'jacket becomes heated the thermostat i 0 will be heated and will move the valve 8 towards its closed position. When the valve 8 is partially closed the cross sectional area of the bypass at this point is reduced and part of the liquid passes through the conduit 3 ,into the radiator 4 and back to the water jacket of the engine. The amount that the valve 8 is closed depends upon the conditions. In hot weather for example, the cooling fluid may reach such a temperature that the valve 8 will be entirely closed and then the cooling liquid will circulate through the main circulatory system, consisting of the water jacket of the engine, the conduit 3, radiator 4 and the return conduit 5. In cold weather the valve 8 may be only'partially closed so that a. portion of the cooling fluid passes continuously through the bypass so, that it will be heated a suillcient temperature to maintain the efli'ciency of the engine and to provide heat for the heaters forrheating the interior oi the automobile. 4
I have found that by properly arranging the parts, the cooling liquid inthe water jacket of the engine may be maintained at the proper temperature for maintaining the efll'ciency of the engine and for use in the heaters, regardless of the low outside temperature and when the engine is running at an exceedingly high speed. In fact, the parts can be arranged so that this liquid may be maintained at the desired temperature -maximum efilciency and the temperature of the become injured. It the thermostat works prop- 19 erly,.then in cold weather and when the engine is running at very high speed, the cooling liquid is cooled to such a degree that the engine is not heated to suflicient temperature to secure its 1 liquid is too low to be effectively used for heating 6 purposes. With the present device these evils are eradicated and in the coldest weather thecooling liquid can be maintained at sufliciently high temperature for eii'ective heating purposes. "With this system, in the very coldest weather the radiator may be substantially out out of circuit except for the flow necessary to prevent stagnation of the liquid therein, and when the weather is not so exceedingly cold the radiator may be alternately cut in and out, and in warmer weather more or less of the radiator utilized as the conditions require, and all this is done automatically and with entire safety to the engine.
With this system there is substantially normal circulation of water through the water jacket at all times, that is when the engine first starts up and at all other times when it is operating, thereby eliminating the possibility of excessive pressure in at the proper temperature occurs in the winter time. In this system even when there are foreign solid particles in the cooling liquid, such particles cannot interfere with the system so as to bring about a condition where the cooling liquid temas perature will be lowered to such anextent as to interfere with the efiiciency of the engine or the temperature which it is desired to maintain. *It will be noted that in this construction the energy of the cooling liquid is utilized to deliver cooling 3 liquid toward or into the bypass.
I claim:
1. A circulatory cooling system for internal combustion engines provided with a water jacket and a radiator, comprising a continuously open main circulating circuit from the water jacket through the radiator for the cooling liquid, and through which a portion of the cooling liquid at all times passes when the engine is running, a bypass around the radiator, through which a portion of the cooling liquid passes when the engine is running,said water jacket having an outletin alignment with the inlet of said bypass.
2. A circulatory cooling system for internal combustion engines provided with a water jacket and a radiator, comprising a continuously open main circulating circuit from the water jacket through the radiator for the cooling liquid, and through which a portion of the cooling liquid at 7 all times passes when the engine is running. a bypass around the radiator. through which a portion of the cooling liquid poses when the engine is running, means for directing water from the water jacket of the engine directly into the inlet end of 76 the bypass and a thermostat located in the bypass intermediate its ends. s 1
3. A circulatory cooling system for internal combustion engines provided with a water jacket and a radiator, comprising a continuously open main circulating circuit from the water jacket through the radiator for the cooling liquid, a bypass around the radiator, means for utilizing the energy of the cooling liquid for directing cooling liquid into said bypass, a valve insaid bypass, normally open when the cooling liquid is cool, a thermostat connected with said valve so as to open it, the thermostat actingto move the valve towardits closed position when the temperature of the cooling liquid rises above apredetermined point.
4. A circulatory cooling system for internal combustion engines provided with a water jacket and a radiator comprising a continuously open main circulating circuit from the water jacket through the radiator for the cooling liquid, a bypass extending from the upper part of the main circulatory circuit to the lower part thereof and provided with a nozzle directed toward the radiator, a valve in said bypass, normally open when the cooling liquid is coolga thermostat connected with said valve so as to operate it, the thermostat acting to move the valve towards its closed position when the'temperature of the cooling liquid rises above a predetermined point.
HAROLD B. DRAPEAU.
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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2517812A (en) * 1948-10-25 1950-08-08 Henry N Wade Water-cooling system
US2556327A (en) * 1948-01-13 1951-06-12 Frederic W Hild Recirculating radiator system
US2593260A (en) * 1946-10-12 1952-04-15 Cutler Hammer Inc Cooling system for electron tubes and other devices
US3285241A (en) * 1960-12-05 1966-11-15 Robertshaw Controls Co Water heater dip tube construction
DE1301630B (en) * 1963-11-27 1969-08-21 Maschf Augsburg Nuernberg Ag Liquid cooling system for internal combustion engines
US5979373A (en) * 1997-05-16 1999-11-09 Nippon Thermostat Co., Ltd. Cooling control system for an internal combustion engine
EP3892839A1 (en) * 2020-04-09 2021-10-13 Caterpillar Motoren GmbH & Co. KG Two-way valve for controlling a temperature of a coolant for an internal combustion engine

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2593260A (en) * 1946-10-12 1952-04-15 Cutler Hammer Inc Cooling system for electron tubes and other devices
US2556327A (en) * 1948-01-13 1951-06-12 Frederic W Hild Recirculating radiator system
US2517812A (en) * 1948-10-25 1950-08-08 Henry N Wade Water-cooling system
US3285241A (en) * 1960-12-05 1966-11-15 Robertshaw Controls Co Water heater dip tube construction
DE1301630B (en) * 1963-11-27 1969-08-21 Maschf Augsburg Nuernberg Ag Liquid cooling system for internal combustion engines
US5979373A (en) * 1997-05-16 1999-11-09 Nippon Thermostat Co., Ltd. Cooling control system for an internal combustion engine
EP3892839A1 (en) * 2020-04-09 2021-10-13 Caterpillar Motoren GmbH & Co. KG Two-way valve for controlling a temperature of a coolant for an internal combustion engine

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