[go: up one dir, main page]

US3805748A - Cooling system for an internal combustion engine - Google Patents

Cooling system for an internal combustion engine Download PDF

Info

Publication number
US3805748A
US3805748A US00223440A US22344072A US3805748A US 3805748 A US3805748 A US 3805748A US 00223440 A US00223440 A US 00223440A US 22344072 A US22344072 A US 22344072A US 3805748 A US3805748 A US 3805748A
Authority
US
United States
Prior art keywords
piping
engine
liquid
valve
radiator
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00223440A
Other languages
English (en)
Inventor
G Garcea
D Radaelli
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alfa Romeo SpA
Original Assignee
Alfa Romeo SpA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Alfa Romeo SpA filed Critical Alfa Romeo SpA
Application granted granted Critical
Publication of US3805748A publication Critical patent/US3805748A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P7/00—Controlling of coolant flow
    • F01P7/14—Controlling of coolant flow the coolant being liquid
    • F01P7/16—Controlling of coolant flow the coolant being liquid by thermostatic control

Definitions

  • a liquid-coolant cooling system for an internal combustion engine of the kind in which a piping bypassing the radiator and put in parallel with respect thereto, is provided, connected by a three-way valve to the radiator inlet piping, the improvement comprising a special throttling valve for the coolant, installed in the radiator-by-passing piping.
  • the special valve allow the rate of flow of liquid through the radiatorby-passing pipe to be increased as the pressure therein is increased.
  • Systems of this kind usually comprise a radiator, which forms the heat-exchanger for exchanging heat with the surrounding atmosphere, and a non-metering pump, driven by the engine, sends the liquid from: the radiatorto appropriate channels formed in the engine block. The liquid flowing through these channels is brought back to the radiator in such a way as to make up a closed loop.
  • the radiator is proportioned consistently with the maximum amount of heat which is to be dissipated.
  • a deflecting valve is provided, as controlled by an element responsive to the temperature of the liquid emerging from the channels of the engine block, in the cooling system, the automatic operation of this valve thus permits the temperature of the liquid may to be maintained virtually constant, so that the engine temperature may stay within an acceptable range, inasmuch as the increase in the resistance in the cooling loop as a consequence of throttling, reduces the rate of flow of the pump.
  • auxiliary piping which permanently by-passes the throttling valve and the radiator, offering hydraulic resistance which is greater than that of the radiator, so that, when the valve is open, the rate of flow in the above mentioned auxiliary piping is not significant as compared with that flowing through the radiator.
  • a further result as attained by the present invention is to reduce to a considerable degree the emission of unburned fractions with the engine exhausts, as compared with the conventional approaches affording similar overheating prevention features.
  • the liquid coolant circulation loop comprises a first piping which includes a radiator, and a second piping mounted in parallel with respect to the radiator by the agency of valve means controlled by means responsive to the temperature of the liquid coolant, to deflect the liquid from the first to the second piping when. the temperature is below a preselected value, and is characterized by a valve, placed in the second piping and governed by means responsive to the power delivered by the engine, the valve being adapted to reduce the flow crosssectional area of said second piping when the engine is running at a low power.
  • the cooling loop according to the present invention comprises a radiator, a first branch of said first piping which connects the liquid delivery side of the radiator to the intake side of a pump whose rate of flow is decreased as the pressure supplied thereby is increased, said pump sending the liquid to the input side of the ducts placed in the interior of the engine block, a second branch of the first piping connecting the output of the liquid of the engine block to the radiator input, the second piping connecting the first branch to the second branch of the first piping, a three-way valve arranged in either of two points of connection of the second piping with the first piping, the three-way valve being controlled by an element sensitive to the temperature of the circulating liquid so that the liquid is circulated through the radiator for temperatures above a preselected level, and, for temperatures below another value which is somewhat lower than the first is circulated through the second piping, whereas for intermediate temperatures it is cir' culated partly through the radiator and partly through the second piping, there being provided in the second piping a throttling
  • FIG. 1 is a diagrammatical showing of a conventional cooling system
  • FIG. 2 is a diagram of the operation of the system of FIG. 1;
  • FIG. 3 is a diagrammatical showing of an alternative conventional embodiment of the cooling system.
  • FIG. 4 is the working diagram of the system of FIG.
  • FIG. 5 shows the cooling system according to the present invention
  • FIG. 6 is the working diagram of the circuit of FIG.
  • FIG. 7 is a cross-sectional view of a valve of the system of FIG. 5, and
  • FIG. 8 is a detail of FIG. 7;
  • FIG. 9 shows the valve of FIG. 7 connected to the throttling valve of the engine feed
  • FIG. 10 shows a further alternative embodiment for controlling the valve of FIG. 7.
  • FIG. 1 there are diagrammatically shown at l the engine block, at 2 the head and at 3 the oil sump tank of a conventional reciprocating internal combustion engine, to whose shaft 4 a flywheel 5 is keyed.
  • the engine block consisting of the engine crankcase l and the head 2 has a net of inner channels therethrough (not shown) for circulating the cooling liquid, these channels being connected to a delivery piping 6 and a discharge piping 7.
  • the latter feeds, through a thermostatic valve 8, a piping 9 which opens into a manifold 10 of a bundle of gilled tubes 11 which is the member which exchanges the heat with the atmosphere.
  • a piping 15, having a reduced cross-sectional area then connects directly the pipings 6 and 13.
  • the non-metering pump 14 for example of the centrifugal type, is driven by the engine, and it is shown in the drawing, for the sake of simplicity, as keyed to the crankshaft 4. At any rate, it can be connected to the crankshaft by any rotational drive, such as by a belt.
  • further conventional members which complete the cooling system have been omitted, such as the fan which thrusts air through the radiator so as to sweep the tubes 11.
  • valve 8 As the engine is started at the temperature of the ambient atmosphere, that is when the engine is cold, the valve 8 is closed by the agency of thermostatic means sensitive to the temperature of the liquid in the piping 7, that is, the liquid flowing out of the engine.
  • the liquid flows through a loop formed by the pump 14, the piping 6, the engine inner channels, the piping 7, l5 and a portion of the piping 13 to the pump again. Due to the presence of the reduced flow cross-sectional area piping 15, the hydraulic resistances of this path are rather high and shown by the line R, of the plot of FIG. 2, as a function of the rate of flow Q.
  • the liquid emerging from the engine is also at a high temperature, for example 85C; the thermostatic valve is then opened and the liquid is allowed to be circulated from the piping 7 through the piping 9, the
  • the principal defect of the cooling loop so embodied has proven to be the small magnitude of the rate of flow q that is, the rate of flow in cold conditions at a high engine rate of rotation.
  • a small rate of flow has proven to be insufficient to prevent hazardous local overheating whenever a cold engine is required to supply high power. That is to say, the velocity of the water flowing through the internal channels of the engine is inadequate to remove the necessary amount of heat from certain areas.
  • the valve 8 enters action for increasing the rate of flow, since its thermostatic control member is responsive only to the temperature of the water emerging from the pipe 7, the water being at an intermediate temperature with respect to that of the different areas of the engine swept thereby.
  • the troubles which can be originated by such over-heating, for example in correspondence of the explosion chambers, are extremely serious and can even cause jamming or perforation of the pistons.
  • FIG. 3 a system of the kind shown in FIG. 3 has been suggested: parts equal to those of the system depicted in FIG. I have been indicated by equal reference numerals.
  • the piping 7 is terminated by a three-way valve 16, which is thermostatically controlled and, when hot, establishes a communication between the tubing 7 and the tubing 9 and, in cold conditions, establishes a communication between the piping 7 and a tubing 17 which, in turn, is in communication with 13 and offers to the liquid a hydraulic resistance which is substantially equal to that of the tubes 11.
  • the liquid flows from the piping 7 to the piping 13 directly via the duct 17 and, in hot conditions, through the ducts 9, 10, 11 and 12, though with the same pressure drop in both cases.
  • the plot of FIG. 4 shows the operability of the loop described immediately above, in the same coordinates as in the loop of FIG. 2.
  • the resistances in the cold and in the hot are represented by the line R R and the rates of flow which pass through the engine either at an average or a high rate of rotation are indicated at q, and q, respectively.
  • the quick attainment of the steady state temperature by the engine is due only to the fact that, in cold conditions, the liquid does not flow through ducts having an intensive heat exchange with the external atmosphere.
  • this second kind of duct it has been made possible to overcome the defects of the system shown in FIG.
  • the circulation of water in the engine is increased as a function of the power delivered by the engine.
  • the cooling system according to the present invention is shown in FIG. 5 and equal componentparts are indicated by equal reference numerals with respect to those already employed for the systems of FIGS. 1 and 3.
  • the piping 17 communicates with the piping 13 through a valve, as generally indicated at 18, which brings about a variable restriction of the cross-sectional area, consistently with the variations of the liquid pressure upstream of the valve.
  • FIG. 7 An example of such a valve 18 is shown in FIG. 7 and consists of a cup 19 integral with the piping l7, and in which an obturator 20 is movable, as biassed by a spring 21 which rests against a bottom wall 22.
  • an obturator 20 is movable, as biassed by a spring 21 which rests against a bottom wall 22.
  • the system according to the invention operates, at a low rate of rotation of the engine, like the system of FIG. 1, .and, at a high rate of rotation of the engine, likethe one of FIG. 3, so that fast warm up of the engine is warranted in correspondence with the explosion chambers without any risk of overheating at high rates of rotation.
  • the opening of the valve 18, and thus the resistance drop in the piping 17, which by-passes the radiator is determined by the increase of the rate of rotation of the engine. Actually, it would be advisable that the resistance drop would be strictly proportional to the power actually delivered by the engine, although it has proven to be sufficient to have the rate of flow of the liquid coolant proportional to other physical units bound to the engine power, such as, as described above, to the rate of rotation of the engine, or the pressure of the pump when the latter is of the centrifugal type.
  • None-the-less other physical units which are a function of the engine power can be useful for controlling the throttling valve in the piping 17: for example the position of the engine feed throttling valve. It is thus possible to arrange in the piping 17 a throttling valve which is driven open when the throttling valve of the engine feed is open. This is obtained by a mere meclianical linkage well-know to persons skilled in the art between the two valves as may be seen in FIG. 9.
  • a rod 25, for example is fastened to the obturator 20 of FIG. 7 and to the accelerator pedal 28 of the vehicle.
  • the accelerator pedal also controls the throttle 32 in the ini take duct of the engine, so that when the pedal 28 is depressed, throttle 32 opens, and element 20 of valve 18 is displaced against the action of the spring 21 thus increasing the passage section for the cooling liquid in theduct 17.
  • the valve in the piping 17 can still be controlled by the pressure obtaining in the engine intake duct, the pressure being increased, as is known, when the throttling valve for the aeriform fluid feeding the engine is opened.
  • the intake duct with a chamber having a wall formed by a deformable diaphragm, the latter being mechanically connected to a throttling valve installed in the piping 17, in such a direction as to close the latter as the feeding pressure is decreased.
  • diaphragm devices which drive a mechanical memberas a function of the pressure obtaining in the intake duct are well known and in the art are usually mounted on internal combustion engines in order to actuate either adjustment mechanisms or servocontrols.
  • a device is shown connected to the valve 18 of FIG. 7, between the valve and the accelerator pedal of the vehicle.
  • the diaphragm 34 of the device together with the rigid wall 35 define a chamber 36 which is connected to the intake duct of the engine.
  • the obturator When the intake duct pressure is low, the obturator is held against the wall 19 so that the passage section is almost throttled. However when the pressure in duct 33 is increased the obturator 20 is displaced by spring 21 so that the passage section of duct 17 is increased.
  • the system according to the present invention affords advantages even when the engine is at its steady state temperature and, however, the valve 16 is in an intermediate position, that is, the liquid partly flows through the radiator and partly through the by-pass piping 17.
  • the resistance of the hydraulic circuit has an intermediate value and, likewise, the rate of flow is comprised between the maximum value under hot conditions and the minimum value under cold conditions.
  • an abruptincrease of the delivered power causes the rate of flow to be immediately increased, preventing overheating which could be experienced if the increase of the rate of flow should require of necessity the operation of the valve 16.
  • this valve has a certain delay at the beginning of its operation due both to thermal inertia and the insertion of thermostatic control means.
  • the three-way valve 16 can merely be replaced by two distinct valves, one on the piping 9 and the other on the piping 17, which are driven open and closed, respectively, by thermostatic means acting in opposite directions.
  • the thermostatically controlled valve installed in the piping 17 could be integral with the valve 18.
  • the position of the pump could 'be varied, by arranging it in any appropriate point of the hydraulic loop.
  • a liquid-coolant cooling system for an internal combustion engine comprising a first piping which includes a radiator, and a second piping placed in parallel with the radiator through valve means governed by means sensitive to the temperature of the liquid coolant for deflecting the liquid from the first to the second piping when said temperature is below a preselected value, characterized by a throttling valve placed in said second piping and governed by means sensitive to the power delivered by th engine, said throttle valve being adapted to reduce the cross-sectional area of said second piping when said power is below preselected value.
  • a cooling system wherein the hydraulic resistance of said second piping with its throttling valve open, is in the same order of magnitude as the hydraulic resistance of the first piping.
  • a cooling system wherein a first branch of said first piping connects the output of liquid from the radiator with the input side of a pump whose rate of flow is decreased as its pressure' is in creased, said pump sending the liquid to the input side of the ducts internal to the engine block, a second branch of said first piping which connects the output of liquid from the engine block with the radiator input, said second piping connecting the first branch to the second branch of the first piping, a three-way valve arranged in one of the points of connection of the second piping with the first piping, said three-way valve being driven by an element sensitive to the temperature of the flowing liquid so that the liquid circulates through the radiator at temperatures over a predetermined value, and at temperatures below another value which is somewhat lower than the first it circulates through the second piping, whereas at intermediate temperatures it partly circulates through the radiator and partly through the second piping, there being provided in said second piping a throttling valve for the liquid flowing therethrough and driven so as to vary the flow crosssectional area for the
  • a cooling system wherein said pump is of the centrifugal type and is driven to rotation by the engine at a speed which is proportional to the speed of rotation of the engine, said throttling valve comprising a movable obturating member, as biassed by a spring, which can be moved from a first position, wherein it leaves said restricted cross-sectional area free for the liquid flow, to a second position wherein it leaves free for the liquid flow said wider cross-sectional area, said obturator being brought from said first to said second position by the pressure differential upstream and downstream of said valve, when said differential exceeds a preselected value.
  • a cooling system wherein said throttling valve is mechanically connected with the adjusting member for the flow of the aeriform fluid fed to the engine in the sense of reducing the crosssectional area of said second piping when said member reduces the flow of the aeriform fluid fed to the engine.
  • a cooling system according to claim 1, wherein said engine has at least one combustion chamber and said throttling valve is driven by a device responsive to the pressure of the aeriform fluid fed to said combustion chambers, in the sense of reducing the crosssectional area of said second piping when said pressure of the aeriform fluid is below certain preselected values.
  • a cooling system wherein said device consists of a chamber placed in communication with a duct through which the aeriform fluid flows towards said combustion chambers, a wall of said chamber being displaceable by the agency of the pressure obtaining in said chamber and being mechanically connected to said throttling valve.
  • a cooling system characterized in that said movable wall is a resiliently yielding diaphragm.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Temperature-Responsive Valves (AREA)
  • Lubrication Of Internal Combustion Engines (AREA)
US00223440A 1971-02-05 1972-02-04 Cooling system for an internal combustion engine Expired - Lifetime US3805748A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT2023671 1971-02-05

Publications (1)

Publication Number Publication Date
US3805748A true US3805748A (en) 1974-04-23

Family

ID=11165011

Family Applications (1)

Application Number Title Priority Date Filing Date
US00223440A Expired - Lifetime US3805748A (en) 1971-02-05 1972-02-04 Cooling system for an internal combustion engine

Country Status (2)

Country Link
US (1) US3805748A (de)
DE (1) DE2205280C2 (de)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4200065A (en) * 1977-05-11 1980-04-29 Maschinenfabrik Augsburg-Nurnberg Aktiengesellschaft Method for preventing undesirable heat losses in a cooling system for liquid-cooled vehicular internal-combustion engines
US4364338A (en) * 1978-10-31 1982-12-21 Alfa Romeo S.P.A. Circuit of the coolant in internal combustion engines for improving engine operation after cold starting
US4425878A (en) 1980-07-10 1984-01-17 Nordstjernan Ab Internal combustion engine cooling method and device
US4436060A (en) 1980-02-01 1984-03-13 Nissan Motor Company, Ltd. Engine cooling system
US4539944A (en) * 1981-04-06 1985-09-10 Alfa Romeo Auto S.P.A. Temperature-controlling system for the liquid coolant of a motor car internal-combustion engine
US4964371A (en) * 1988-04-04 1990-10-23 Mazda Motor Corporation Automobile engine cooling system
US5381763A (en) * 1993-09-28 1995-01-17 Outboard Marine Corporation Dry head cooling system
US5967101A (en) * 1998-05-01 1999-10-19 Chrysler Corporation Engine cooling system and thermostat with improved bypass control
US6634322B2 (en) * 2001-04-12 2003-10-21 Cold Fire, Llc Heat exchanger tempering valve

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3715003A1 (de) * 1987-05-06 1988-11-17 Kloeckner Humboldt Deutz Ag Kuehlsystem fuer eine fluessigkeitsgekuehlte brennkraftmaschine

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1253695A (en) * 1915-08-10 1918-01-15 Motor Cooling Systems Company Circulation control.
US1649248A (en) * 1923-08-24 1927-11-15 Wellington W Muir Automatic cooling system
US1785207A (en) * 1927-07-11 1930-12-16 Stanley H Page Motor-temperature-controlling means
US2500472A (en) * 1948-10-20 1950-03-14 Lawrence J Sohler Control for coolants in liquid cooled motors
US2622572A (en) * 1949-11-28 1952-12-23 Daimler Benz Ag Device for the control of the temperature in combustion engines
US2808038A (en) * 1953-04-02 1957-10-01 Daimler Benz Ag Control system for an internal combustion piston engine, particularly for motor vehicles
US3459161A (en) * 1966-12-03 1969-08-05 Daimler Benz Ag Installation for controlling the cooling medium temperature to a predetermined desired value with an internal combustion engine

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR990664A (fr) * 1944-03-24 1951-09-25 Million Guiet Tubauto Dispositif de réchauffage et de maintien au-dessous d'une température maximum de l'huile de lubrification de moteurs à combustion interne
DE1119053B (de) * 1958-04-12 1961-12-07 Daimler Benz Ag Einrichtung zum Regeln der Temperatur eines fluessigen Waermetraegers von Waermekraftanlagen, insbesondere Brennkraftmaschinen
US3080857A (en) * 1960-12-14 1963-03-12 Int Harvester Co Engine coolant system

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1253695A (en) * 1915-08-10 1918-01-15 Motor Cooling Systems Company Circulation control.
US1649248A (en) * 1923-08-24 1927-11-15 Wellington W Muir Automatic cooling system
US1785207A (en) * 1927-07-11 1930-12-16 Stanley H Page Motor-temperature-controlling means
US2500472A (en) * 1948-10-20 1950-03-14 Lawrence J Sohler Control for coolants in liquid cooled motors
US2622572A (en) * 1949-11-28 1952-12-23 Daimler Benz Ag Device for the control of the temperature in combustion engines
US2808038A (en) * 1953-04-02 1957-10-01 Daimler Benz Ag Control system for an internal combustion piston engine, particularly for motor vehicles
US3459161A (en) * 1966-12-03 1969-08-05 Daimler Benz Ag Installation for controlling the cooling medium temperature to a predetermined desired value with an internal combustion engine

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4200065A (en) * 1977-05-11 1980-04-29 Maschinenfabrik Augsburg-Nurnberg Aktiengesellschaft Method for preventing undesirable heat losses in a cooling system for liquid-cooled vehicular internal-combustion engines
US4364338A (en) * 1978-10-31 1982-12-21 Alfa Romeo S.P.A. Circuit of the coolant in internal combustion engines for improving engine operation after cold starting
US4436060A (en) 1980-02-01 1984-03-13 Nissan Motor Company, Ltd. Engine cooling system
US4425878A (en) 1980-07-10 1984-01-17 Nordstjernan Ab Internal combustion engine cooling method and device
US4539944A (en) * 1981-04-06 1985-09-10 Alfa Romeo Auto S.P.A. Temperature-controlling system for the liquid coolant of a motor car internal-combustion engine
US4964371A (en) * 1988-04-04 1990-10-23 Mazda Motor Corporation Automobile engine cooling system
US5381763A (en) * 1993-09-28 1995-01-17 Outboard Marine Corporation Dry head cooling system
US5967101A (en) * 1998-05-01 1999-10-19 Chrysler Corporation Engine cooling system and thermostat with improved bypass control
US6634322B2 (en) * 2001-04-12 2003-10-21 Cold Fire, Llc Heat exchanger tempering valve

Also Published As

Publication number Publication date
DE2205280C2 (de) 1984-02-09
DE2205280A1 (de) 1972-08-17

Similar Documents

Publication Publication Date Title
US4325219A (en) Two loop engine coolant system
US3851629A (en) Cooling installation for piston internal combustion engines
US4620509A (en) Twin-flow cooling system
US4538553A (en) Mode of control of the heating capacity of a hydrodynamic brake
US8109242B2 (en) Multi-thermostat engine cooling system
US5551384A (en) System for heating temperature control fluid using the engine exhaust manifold
GB2146760A (en) Cooling system for an i c engine
JPS61294162A (ja) 内燃機関用の燃料供給装置
US3805748A (en) Cooling system for an internal combustion engine
GB2055963A (en) Supercharging Internal Combustion Engines
US5860595A (en) Motor vehicle heat exhanger
WO1980000863A1 (en) Fresh water cooling system for compressed charged i.c.engines
US4483150A (en) Supercharged internal combustion engines provided with a cooling system
US1998636A (en) Intake manifold heating device
US2369937A (en) Carburetor intake air heater
US4457727A (en) Marine propulsion device engine cooling system
US4356796A (en) Cooling system for hydronamic retarder of internal combustion engine
US2133514A (en) Engine cooling system
JPH05209529A (ja) ２段階式の過給空気冷却機構を備えた内燃機関
US3797562A (en) Cooling systems of supercharged diesel engines
US3814071A (en) Coolant temperature responsive exhaust crossover valve system
US3442258A (en) Internal combustion engine in which cooling medium is supplied from a primary cooling installation for the engine cooling to a secondary cooling installation for the precompressed combustion air
GB2366365A (en) Engine Cooling system
GB2442839A (en) Cooling system for an internal combustion engine comprising an exhaust gas cooler
GB2058911A (en) Cooling vehicle oils by the engine combustion air