DE4033261A1 - Cooling system for combustion engine - has control unit to regulate mass flow - Google Patents

Abstract

Combustion engine (1) contg. within it a cooling medium pipe (2) through which a cooling medium can flow. The mass flow of the cooling medium is regulated by a temp-responsive control (25) acting on the valves forming part of an auxiliary unit (3). ADVANTAGE - Combustion engine having a cooling system which ensures the optimal operating temp. is rapidly reached and maintained.

Description

The invention relates to an internal combustion engine a coolant line contained therein, which by a liquid coolant can be flowed through.

Such an internal combustion engine is general known. It arrives for example in motor vehicles Application and includes two coolant circuits. A Short circuit leads the internal combustion engine the heated coolant without cooling again. In the cooler circuit, the coolant flows through a heat exchanger, before it is fed back to the internal combustion engine becomes. Excess heat is in the heat exchanger dissipated and delivered to a secondary coolant.

Both circuits of the coolant of the internal combustion engine machine can be moved simultaneously or in time be switched on. Through the targeted distribution of the The coolant mass flow on both circuits is the Controlled coolant temperature. The coolant mass flow by the internal combustion engine is by the rain However, the coolant temperature is insufficient influenced. The temperature can also be determined in this way the components of the combustion in contact with the combustion chamber insufficiently to one for a favorable combustion process an optimal value put.

The invention has for its object a combustion engine of the type mentioned in this way wrap that a faster after a commissioning  Heating of the engine components touching the combustion chamber to an optimal operating temperature and at which the optimal operating temperature regardless of the Maintaining constant load largely constant becomes.

This object is achieved in a combustion Engine of the type mentioned with the ident drawing features of claim 1 solved. On advantage Adhesive refinements refer to claims 2 to 23.

It is in the internal combustion engine according to the invention provided that the coolant line at least one Aid for reducing the coolant mass flow assigned. The coolant line denotes in this Senses that space within the combustion force machine in which the transfer of excess heat the liquid coolant is effected. The coolant room can include different subspaces and the rest in Depends on the requirements of the application be designed. The coolant can be Trade water containing antifreeze.

By reducing the mass flow of the cooling by means of the coolant line is caused to after commissioning the internal combustion engine much faster heating of the combustion chamber touch renden parts results than in the known version. The optimal operating temperature becomes essential achieved shorter time and thus a basic condition for achieving a favorable combustion process he fills. Wear and increased pollutant emissions during the warm-up phase is significantly reduced.  

The reduction of the coolant mass flow through the Coolant line can be done in a targeted manner. The tools required for this can be found within the Internal combustion engine in the coolant line in front be seen. This is particularly supported by the fact that less Auxiliary units around the internal combustion engine are to be accommodated. This results in a better one Clarity in the engine compartment.

An attachment of the aids outside the cremation engine has the advantage of better maintenance friendliness, because in the event of a repair need results in better accessibility.

The tool for reducing the coolant masses can flow the inlet or outlet of the coolant be assigned to the line. This makes it possible to Cooling system the spatial conditions of the installation space better adapt.

Is the aid of the inlet and outlet opening of the cooling assigned to the central line, there is an improved Operational safety.

The aid can consist of a valve that on seals against a valve seat and in the front Coolant line is installed. Such cooling systems can easily and inexpensively manufactured in large quantities will.

The aid can also consist of a valve that one, which can be immersed in a valve seat, at the front end cone-shaped piston containing the flow through the  Coolant line regulated. The advantage is with a linear adjustment path is not the adjustment path to open proportional circular surfaces as an opening. The shape of the cone influences the opening characteristic cross-section over the adjustment path.

The valve, which is used as an aid, can be turned off one, which can be immersed in a valve seat, at the front end stepped pistons exist. The flow cross section the coolant line is exposed in so many stages ben how the stepped piston has paragraphs.

The height or length as well as the diameter of the steps are exactly to the respective temperatures of the combustion engine matched to the different load cases. So there is a short warm-up phase and then one uniform temperature guaranteed.

The aid can be designed lamellar. Then result from connecting at least two in series, for example, lamellar discs, a large number different flow cross-sections. Through the combination different lamellar tools, the cooling systems can be based on the modular principle match the respective internal combustion engines.

The modular principle enables an inexpensive Production of lamellar tool. The lamel len-like aids, for example, consists of a rotatably mounted and one fixed in the coolant flow standing disc that are interconnected. The rotatably mounted disc can e.g. B. on the circumference with a Gear rim for the drive. By the more or less close match between the openings of the two The coolant mass flow is adjustable.  

The tool can be used as a control spool with various large flow cross-sections. The Coolant mass flow is the flow cross section of the different slide positions proportional. Is that for Cooling of the internal combustion engine required coolant tel mass flow under different operating conditions exactly known, this can be, for example, three various, precisely defined slide positions, achieve exactly. This solution enables an uncomplicated graceful, reliable regulation of the coolant masses current.

The tool can consist of a slide, which as Rotary valve is formed. The size and number of Bores and the open flow cross-section are decisive for the cooling effect. Even with this aid the advantage is an inexpensive production according to the modular principle. Similar to the slats Aids are designed by combining the Discs of different coolant mass flows through the cooling system possible, so that for any combustion power the right cooling system with little effort pose is.

The tool can consist of a slide, which as Flat slide is formed. Here is the mass flow the coolant is reduced in a particularly simple manner. In particular, there are few components and a simple structure the characteristics of this solution.

Another aid consists of a centrifugal pump, the with a device for reversing the direction of rotation is provided, so that the effect of a brake pump  results. The coolant mass flow through the coolant Cable can be clocked in steps as well as continuously be controllable. The coolant mass flow depends on the Direction of rotation and the speed of rotation of the brake pump off.

The aid can consist of at least two control elements exist and the two control elements can work together in be arranged in a housing.

In addition, the two control elements are independent of one another other controllable. The advantage here is that both the Component temperature as well as the coolant temperature Influence on the coolant mass flow and the path of the Have coolant through the system. The actuation of the Control elements can be made using temperature sensors and a map that are stored in a control unit is.

The tools listed so far can by Signal of at least one temperature sensor can be controlled, the temperature sensor as a component temperature sensor and / or be designed as a coolant temperature sensor can. As a result, the coolant mass flow through the Coolant line in direct connection with the component temperature and / or the coolant temperature of the combustion machine.

In addition, the aids can have at least one servo drive be assigned, which can be actuated pneumatically, for example is. Especially with diesel internal combustion engines is this actuation by the already existing sub pressure (preferably for cars) or overpressure (preferred wise for trucks) advantageous.  

If the servo drive can be operated hydraulically, it is intended for vehicles with hydraulic auxiliary drives. A hydraulic auxiliary drive must, for example, in Vehicles with power steering are available.

A servo drive can also be assigned to the aid be, for example, which can be operated electrically. This option of activity is used in most Cases. Electrical energy is at Get internal combustion engines from the battery.

The servo drive is through the actuator of a thermocouple mentes formed and the thermocouple is the one in the Liquid and / or min at least one component of the internal combustion engine net that directly touches the combustion chamber.

An assignment to that contained in the coolant line Liquid is technically better and easier realize. A much more sensitive control of the Operating behavior of the internal combustion engine can on the other hand, achieve an assignment to the distillery components of the internal combustion engine is made. There is also the possibility of this changes that occur under normal operating conditions the temperature of the liquid and / or the components stored electronically in a map and using the operating point of combustion engine parameters and call to control the reduction of the mass flow of the To use coolant-causing aids. Some related parameters can, for example, the amount of fuel injected represent the load condition  of the internal combustion engine, the speed of the crank wave and / or the ignition timing. Such parameters can also be used to immediately calculate an optimal Adjustment of the aid can be used.

Are the actuators of the thermocouples such as For example, a bimetal spring or a liquid-filled one Hollow body that is only stretchable in one direction Coolant line, the adjustment of the auxiliary is not necessary from outside. The automatic regulation is simple under construction and also to the respective operating temperature The internal combustion engine can be tuned.

The advantages achieved with the invention are in particular the fact that the internal combustion engine after Commissioning by the individual on the respective Operating state of coordinated cooling of the engine components warms up particularly quickly and reduces wear having. As a result, a longer service life is achieved and the machine is more economical to operate. Regarding harmful exhaust emissions, there is a significant improvement and a reduction in the spec fish fuel consumption. Advantageous beyond that is that the heating circuit, which is used to heat the Vehicle interior provided and usually the Cooling circuit is connected in parallel, an aid to Limitation of the coolant mass flow must be assigned can. This will make the flow through the heating circuit only run at the optimal operating temperatures of the machine Approved. There is also the possibility of the Hei cycle with low partial load operation of the combustion machine to close the machine Extract heat for heating the vehicle interior and thereby the favorable for the combustion process Keep temperatures longer.

The following description of several embodiments games of the invention is used in connection with the drawing further explanation.

In Figs. 1, 2, 2a, 2b and 3, a combustion is combustion engine 1 shown in working condition. The internal combustion engine according to the invention can be operated using various working methods, such as the Otto or diesel principle. The piston 8 moves up and down in a cylinder 9 . It is attached to a crank shaft 11 by means of a connecting rod 10 . The crankshaft 11 is thereby rotated. In Otto engines, a combustible mixture is fed into the cylinder of FIG. 9 by means of an intake line 12, for example via at least one valve 13 , and is ignited and burned in a known manner. In diesel engines, air enters through an intake line 12, for example, via at least one valve 13 in the cylinder 9 , is compressed, acted upon by fuel and also ignited and burned in a known manner. The heat released is only partially converted into kinetic energy. The excess heat must therefore be continuously removed to prevent damage to the internal combustion engine due to overheating. The cylinder 9 , which normally consists of a metallic material, is therefore usually surrounded by a water jacket 14 , which also fills a part of the cylinder head 15 . The water jacket 14 is contained in a cavity, which is referred to as a line in the context of the patent application for reasons of simplification and is connected to an inlet 16 and outlet line 17 . The inlet 16 and outlet line 17 can, as shown in FIGS. 1, 2, 2a and 2b, be connected outside the internal combustion engine by a short circuit line 18 , with a thermostatic valve 19 or an actuating element 26 at the input or output of the short circuit line 18 is provided.

Fig. 1 corresponds in structure and mode of operation to the known cooling systems for cooling internal combustion engines. Figs. 2, 2a, 2b, and 3 illustrate the invention in four application examples are described in detail below.

In Figs. 2, 2a and 2b in a parallel circuit to the short-circuit line 18, a cooler 20 is provided, which is designed as a heat exchanger and in parallel of a plurality of thin-walled metal pipes is, the flow around the outside of cooling air 21. In Fig. 2 closes the short circuit 18 when a sufficiently high operating temperature of the thermostat 19th The heated coolant discharged from the drain line 17 is thereby forced to make its way through the cooler 20 , resulting in a lowering of its temperature. A centrifugal pump 22 is provided for the return to the coolant line 2 of the internal combustion engine. Between the centrifugal pump 22 and the coolant line 2 , a drive 3 provided with a servo drive 23 is provided, which is connected in a signal-conducting manner to a temperature sensor 24. The temperature sensor 24 can be designed as a component temperature sensor or as a coolant temperature sensor.

In the case of internal combustion engines which have an electronic engine control system, there is also the possibility of connecting the auxiliary means 3 to them in a signal-conducting manner and to control them in this way.

In the case of a cold internal combustion engine, the coolant mass flow is closed by the auxiliary means 3 . The coolant contained in the coolant line 2 is prevented by a circulation through the internal combustion engine, which requires a particularly rapid heating. When the operating temperature is reached, the auxiliary device 3 is gradually brought into the open position by means of an electrical signal by the temperature sensor 24 , which should expediently be arranged adjacent to one of the warmest points of the internal combustion engine. The thermostatic valve 19 is still in the open position, so that the coolant flowing out of the return line 17 is fed via the short-circuit line 18 to the centrifugal pump 22 and fed again into the coolant line 2 at the lower end.

When the temperature of the coolant in the coolant line 2 increases further, the short-circuit line 18 is gradually closed by the thermostat 19 and the path through the cooler 20 is gradually opened. The coolant is cooled in the cooler so far that the internal combustion engine takes no damage regardless of the load. The presence of the auxiliary means 3 thus significantly shortens the warm-up phase.

Fig. 2a forms the example of an internal combustion engine shown in Fig. 2 in such a way that the aid 3 consists of three actuating elements 26 , 27 , 28 , which are housed in a housing and each signallei tend connected to a control unit 25 .

All three control elements 26 , 27 , 28 can be actuated separately. The advantage here is that both the coolant temperature and the engine component temperature have an influence on the coolant mass flow through the system. The signal transmission can be carried out by means of a map in conjunction with temperature sensors 24. The heating circuit can also be operated by the control unit 25 .

When the internal combustion engine is cold, the adjusting elements 26 , 27 , 28 close the adjacent lines. Because the coolant is prevented from circulating through the machine and the cooling system, the internal combustion engine heats up rapidly. Reaches the combustion chamber wall, the control element 26 gradually opens the flow and the coolant is heated in the short circuit 18 . The end of the warm-up phase is reached when the coolant has reached its target temperature in the short circuit. If the temperatures of the internal combustion engine continue to rise, the cooler circuit and / or the heating circuit must be opened in addition to the short circuit. Optimal engine component temperatures are achieved by setting an appropriate coolant mass flow through the internal combustion engine. The heat transfer and heat transfer are adapted to the operating points of the machine. The actuating elements 26 , 27 , 28 release a total cross-section determined by the control device 25 and at the same time regulate the coolant temperature by distributing the coolant mass flow to the short-circuit and cooler and / or heating circuit 29 . By dividing the coolant mass flow to short circuit, radiator and heating, both the desired vehicle interior temperature and the optimum combustion chamber temperature are set. The vehicle interior temperature can be detected by a temperature sensor 30 . By closing the Stellele elements 26 and / or 27 , the coolant mass flow through the heater can be increased if necessary.

As an alternative to the solution variant shown in FIG. 2a, it is also possible to control the coolant mass flow through the heating circuit via, for example, a manually operated slide. However, a distribution of the coolant mass flow within the internal combustion engine tailored to the optimum temperature of the internal combustion engine is difficult to achieve. Of course, it is important to ensure that the adjusting elements 26 , 27 , 28 are properly coordinated with one another. The map is based on the data from the engine management. In the cases in which the technical requirements for the installation and functioning of this solution variant are given, this embodiment of the internal combustion engine according to the invention represents a relatively simple, reliable, variable and the already existing data of the engine management solution.

In contrast to the throttle control of the coolant mass flow of the internal combustion engine from FIGS . 1, 2, 2a and the following Fig. 3, Fig. 2b represents a bypass control of the coolant mass flow through the coolant line 2. Experiments have shown that a Separately adjustable, decoupled circulation through the internal combustion engine and the line connected outside can be useful. The advantage here is that when the coolant is circulated through the line outside the internal combustion engine, no gases get into the water pump 22 , so that no cavitation occurs and no problems with venting the cooling system occur. The arrangement shown here as an example allows the most sensitive and functionally reliable metering of the coolant mass flow through the coolant line 2 . The thermostat 19 and the auxiliary means 3 can also be accommodated together in one housing, as in FIG. 2a. Both the thermostat 19 and the aid 3 can be controlled by separate temperature sensors or can be controlled via a map that is provided with the data of an existing engine control. If the flow of the coolant mass flow through the coolant line 2 can be stopped, the short-circuit line 18 and a bypass line 26 , as shown in FIG. 2b, can even be omitted, as shown in FIG. 3. The cooling system now has only one circuit, which ensures both rapid heating and, especially with stationary engines, a sufficiently uniform, thermal load on the internal combustion engine. A wide variety of aids 3 , also in combination, can be used to regulate the coolant mass flow according to the invention.

Figs. 4 to 13 are embodiments which are described below:

Fig. 4 is an example of an aid 3 in the form of a valve 3.1 , which is built into the coolant line 2 . In FIG. 4 is, as in FIGS. 5 to 13 also cause tool 3, each line the throttling of the coolant mass flow in the cooling means 2.

Depending on the temperature of the coolant and / or the engine components, the valve 3.1 opens more or less the flow cross section through the coolant line 2 .

Closes the valve 3.1 the coolant line 2 completely, the machine quickly reaches its operating temperature without long and wear-promoting warm-up phases. If the valve 3.1 is fully open, the coolant mass flow is so large that the internal combustion engine is not damaged even at full load.

In Fig. 5, a conical piston 3.2 is shown, which installed in the refrigerant line, regulates the coolant mass flow. The shape of the cone above the valve seat influences the non-linear characteristic of the opening cross-section over the adjustment path.

In Fig. 6 the flow cross-section is regulated via a stepped piston 3.4 . The stepped piston 3.4 , which is attached in the coolant line 2 , gradually releases different opening cross sections in the line. Via the height or length of the individual sections and their diameter, the stepped piston 3.4 can be adjusted to the specific temperatures of the respective internal combustion engine. When the machine is cold, the stepped piston 3.4 completely closes the opening in the coolant line 2 . With increasing heating of the coolant and / or the engine components, the stepped piston 3.4 releases an increasingly larger opening cross section. The largest opening cross-section is designed so that overheating of the engine is excluded even at full load.

In Fig. 7 the aid is lamellar 3.3 Darge provides. It is composed, for example, of two disks 3.3.1 and 3.3.2, one behind the other, with lamellar openings which are provided in the coolant line. One of the disks is permanently installed in the coolant circuit, the other is rotatable relative to the first disk. The rotatably mounted disk can be driven, for example, on the circumference by means of a ring gear 3.3.3 .

The coolant mass flow can be adjusted by the more or less large correspondence of the openings of the two disks 3.3.1 and 3.3.2 . By combining different disks, which are arranged one behind the other, any coolant mass flow can be set.

The advantage of the lamellar tool 3.3 is its great versatility. Such aids can be used universally for any internal combustion engine. The manufacture of the lamellar auxiliary means 3.3 is particularly economical due to the modular principle.

The aid shown in FIG. 8 is a control slide 3.9 (3-way). In technical applications in which a 3-stage control, as exemplified here, is sufficient, this solution represents a more uncomplicated, easier to set, reliable and inexpensive control of the coolant mass flow through the coolant line 2 .

The aid in FIG. 9 represents a slide which is designed as a rotary slide 3.5 . The rotary valve 3.5 consists, for example, of two disks 3.5.1 and 3.5.2 , one of which is permanently installed in the coolant circuit and the other of which is rotatably mounted relative to the first. The size and number of openings in both disks 3.5.1 and 3.5.2 as well as the open flow cross section are decisive for the flow through the coolant line 2 . By combining different discs, the cooling effect can be individually tailored to each internal combustion engine. The rotatably mounted disk can be driven, for example, via a toothed ring which is attached to the circumference. This tool also enables cost-effective modular construction.

In Fig. 10, the aid 3 is designed as a flat slide 3.6 . The flat slide 3.6 regulates the coolant mass flow in the coolant circuit and has its advantages in the simple, low-part construction.

Fig. 11 shows as an aid 3 is a centrifugal pump, which is designed as a brake pump 3.7. It is provided with a device for reversing the direction of rotation. The coolant mass flow through the coolant line 2 depends both on the direction of rotation of the brake pump 3.7 and on its rotational speed. These possibilities of exerting influence quickly reach the operating temperature by greatly reducing the coolant mass flow, in which the brake pump 3.7 rotates against the direction of movement of the coolant. However, it should be noted that a complete suppression of the circulation is hardly possible and also makes no sense with this solution variant. With increasing operating temperature, the speed of rotation of the brake pump 3.7 decreases. When the operating temperature is reached, its rotor moves in the direction of the flowing cooling medium. The flow of the coolant through the coolant line 2 is now the greatest. The internal combustion engine is protected against excessive thermal stress.

Fig. 12 shows a servo drive 3.8 , which is associated with the auxiliary tel 3 . The servo drive 3.8 is operated pneumatically, for example. When the machine is cold, the stepped piston 3.8.1 is pressurized with compressed air from above. The flow opening through the coolant line is blocked. As the temperature increases, the stepped piston 3.8.1 is acted upon from below with compressed air and gradually releases the flow opening through the coolant line 2 . Fig. 12 is also used in unchanged form for a servo drive that can be operated hydraulically.

Fig. 13 shows a liquid-filled hollow body 7, which is designed as a stretching member and stretchable only in the longitudinal direction. The liquid-filled hollow body 7 releases the coolant flow depending on the temperature change of the medium surrounding it. The media can be both liquid media such. B. coolant as well as solid media, such as cylinder openings. With the help of such a liquid-filled hollow body 7 , a coolant temperature control and / or a component temperature control can take place. In a cold internal combustion engine, the liquid-filled hollow body 7 is the shortest and closes the flow opening through the coolant line 2 . With increasing coolant temperature and / or engine component temperature, the liquid-filled hollow body 7 heats up and expands. As the length changes, it continues to open the flow opening. The liquid-filled hollow body 7 can be adjusted to the respective operating temperature behavior of various internal combustion engines, in which a liquid is filled with different coefficients of thermal expansion in the hollow body. Automatic control and simple construction are particularly advantageous for liquid-filled expansion elements.

Claims (23)

1. Internal combustion engine with a coolant line contained therein, through which a liquid coolant can flow, characterized in that the coolant line ( 2 ) is assigned at least one aid ( 3 ) for reducing the coolant mass flow. 2. Internal combustion engine according to claim 1, characterized in that the auxiliary means ( 3 ) of the inlet ( 4 ) or outlet opening ( 5 ) of the coolant line ( 2 ) is assigned. 3. Internal combustion engine according to claim 1, characterized in that the auxiliary means ( 3 ) of the inlet ( 4 ) and outlet opening ( 5 ) of the coolant line ( 2 ) is assigned. 4. Internal combustion engine according to claim 1 to 3, characterized in that the auxiliary means ( 3 ) consists of at least one valve ( 3.1 ). 5. Internal combustion engine according to claim 1 to 4, characterized in that the valve ( 3.1 ) contains a plunged into a valve seat, at the front end conical piston ( 3.2 ). 6. Internal combustion engine according to claim 4, characterized in that the valve ( 3.1 ) contains a plunged into a valve seat, at the front end stepped piston ( 3.4 ). 7. Internal combustion engine according to claim 1 to 3, characterized in that the aid ( 3 ) is designed lamellar ( 3.3 ). 8. Internal combustion engine according to claim 1 to 3, characterized in that the auxiliary means ( 3 ) consists of a slide. 9. Internal combustion engine according to claim 8, characterized in that the slide is designed as a control slide ( 3.9 ) with differently sized flow cross sections. 10. Internal combustion engine according to claim 8, characterized in that the slide is designed as a rotary slide ( 3.5 ). 11. Internal combustion engine according to claim 8, characterized in that the slide is designed as a flat slide ( 3.6 ). 12. Internal combustion engine according to claim 1 to 3, characterized in that the auxiliary means ( 3 ) consists of a brake pump ( 3.7 ). 13. Internal combustion engine according to claim 12, characterized in that the brake pump ( 3.7 ) is provided with a device for reversing the direction of rotation. 14. Internal combustion engine according to claim 1 to 3, characterized in that the auxiliary means ( 3 ) consists of at least two adjusting elements ( 26 , 27 ) and that the two adjusting elements ( 26 , 27 ) are arranged together in one housing. 15. Internal combustion engine according to claim 14, characterized in that the two adjusting elements ( 26 , 27 ) can be controlled independently of one another. 16. Internal combustion engine according to claim 1 to 15, characterized in that the auxiliary means ( 3 ) can be controlled by the signal of at least one temperature sensor ( 24 ) and that the temperature sensor ( 24 ) is designed as a component temperature sensor and / or as a coolant temperature sensor. 17. Internal combustion engine according to claim 1 to 15, characterized in that the auxiliary means ( 3 ) is assigned at least one servo drive ( 3.8 ). 18. Internal combustion engine according to claim 17, characterized in that the servo drive ( 3.8 ) is pneumatically operable. 19. Internal combustion engine according to claim 17, characterized in that the servo drive ( 3.8 ) is hydraulically operable. 20. Internal combustion engine according to claim 17, characterized in that the servo drive ( 3.8 ) is electrically actuated. 21. Internal combustion engine according to claim 17, characterized in that the servo drive ( 3.8 ) is formed by the actuator of a thermocouple and that the thermocouple is associated with the liquid contained in the coolant line ( 2 ) and / or at least one component of the internal combustion engine ( 1 ), that directly touches the combustion chamber. 22. Internal combustion engine according to claim 21, characterized characterized in that the actuator of the thermocouple tes contains a bimetal spring. 23. Internal combustion engine according to claim 21, characterized in that the actuator of the Thermoelemen tes comprises a liquid-filled hollow body ( 7 ) which is only expandable in one direction.