FR3040433A1 - TURBO-PRESSURIZED MOTOR VEHICLE ENGINE WITH COOLING SYSTEM DEDICATED TO TURBOCHARGER - Google Patents

Abstract

A motor vehicle engine comprising: - an engine lubrication system provided with a support (7), - at least one cooling system provided with at least one coolant pump (18), the engine comprising a turbocharger (3) adapted to supercharge the engine air, the coolant pump comprising a single outlet (22) connected to the turbocharger for cooling thereof.

Description

TURBO-PRESSURIZED MOTOR VEHICLE ENGINE WITH COOLING SYSTEM

DEDICATED TO THE TURBOCHARGER

The present invention relates to a lubrication system of an engine assembly provided with a turbocharger, and a cooling system of the turbocharger.

A lubrication system has several functions: - to participate in the reduction of friction of moving parts; - participate in the dissipation of some of the heat generated in the engine; - participate in the sealing of cylinders; - to facilitate the evacuation, during emptying, of particles due to wear and combustion residues.

In order to obtain these functions, the lubrication consists, in a non-exhaustive manner, in lubricating the crankshaft bearings, the pistons and the bearings of camshafts. For this purpose, the lubrication system comprises a lubrication circuit provided with at least one oil pump and an oil filter.

The cooling is intended to cool the cylinder block of an engine, the oil of the lubrication system, as well as other components of the motor vehicle if necessary, by circulating the coolant therein.

The cooling of the engine is, in a simplified manner, by means of a cooling system comprising a cooling circuit provided with a main pump, a thermostat and a motor-ventilated radiator. The cooling of the oil of the cooling system is obtained for example by means of a heat exchanger, allowing heat exchange between the lubrication circuit and the cooling circuit.

These systems are relatively bulky and can weigh heavily. In addition, they include many parts, which complicate the assembly and involve high costs.

To reduce the volume and weight of these systems, document CN 101 435 365 discloses a motor vehicle engine comprising: a motor lubrication system, provided with an oil filter, a heat exchanger, heat to cool the oil, and a support, - a cooling system, provided with a coolant pump.

In this prior document, the oil filter, the heat exchanger and the coolant pump are mounted on the support, so as to form a unitary block. By "unitary" is meant that no pipe connects these different elements together. The fluidic connections between these elements are made by mechanical coupling to the support.

The cooling system described in the document cited above has at least one important defect. When the engine is supercharged with a turbocharger, it is necessary to cool the engine when the engine is stopped. However, the use of a pump to cool several elements of the motor vehicle does not provide optimum performance for cooling the turbocharger. The risk is that it deteriorates, under the effect of temperature, once the vehicle engine stopped.

A first objective is to provide a motor vehicle engine equipped with a cooling system dedicated to the turbocharger, especially when the engine of the vehicle is at a standstill.

A second objective is to provide a lubrication system and a turbocharger cooling system that is compact.

A third objective is to limit the number of parts in such a cooling system.

A fourth objective is to limit the pressure losses in such a cooling system.

For this purpose, it is proposed, in the first place, a motor vehicle engine comprising: - a lubrication system of the engine, provided with a support, - at least one cooling system, provided with at least one coolant pump, the engine comprising a turbocharger adapted to supercharge the engine air, the coolant pump comprising a single output connected to the turbocharger for cooling thereof.

[0014] Advantageously, the lubrication system comprises at least one oil filter mounted on the support.

[0015] Advantageously, the lubrication system comprises at least one heat exchanger mounted on the support.

The mounting of the oil filter, the heat exchanger, and the coolant pump on the same support provides a great compactness and limits the number of parts usually used. Such an assembly also makes it possible to limit the pressure drops, in favor of the cooling efficiency of the turbocharger.

The coolant pump is dedicated solely to the cooling of the turbocharger, which allows to cool optimally.

Various additional features may be provided, alone or in combination: a single inlet of the coolant pump between which the coolant is positioned opposite a water outlet of the heat exchanger; the coolant pump is electric, and comprises an electrical connector against to be connected to an electrical connector of an electrical system and control of the motor vehicle; the support comprises an attached lid, the latter covering the coolant pump projecting from the support; the cover comprises means for fixing to the support; the cover comprises a connection hose extending projecting from the side of a side wall, the connection hose being adapted to be connected to a cooling pipe connecting the single outlet to the turbocharger, for the cooling thereof; the cover comprises an outer electrical connector, projecting from the side of an outer face thereof, and an inner electrical connector projecting from an inner side, the outer electrical connector being connected to the electrical connector of an electrical and control system of the motor vehicle, the inner electrical connector being connected to the electrical connector against the coolant pump; the external electrical connector against comprises holding clips, able to maintain the electrical connector of the electrical system and control; the support material is an aluminum alloy.

It is proposed, secondly, a motor vehicle comprising a motor as previously described.

Other characteristics and advantages of the invention will appear more clearly and concretely on reading the following description of embodiments, which is made with reference to the accompanying drawings, in which: FIG. perspective view of a motor vehicle, equipped with a supercharged air motor by a turbocharger, Figure 2 is a schematic representation of a four-cylinder engine supercharged by a turbocharger, and comprising a cooling system of said turbocharger, the FIG. 3 is a diagrammatic representation of a cooling and lubricating system for an engine and a cooling and lubricating system for a turbocharger, FIG. 4 is a perspective view of a turbocharger, equipped with a support comprising a part of the cooling system of the turbocharger, FIG. 5 is a view similar to that of FIG. 4 in which the support is provided with a protective cover, FIG. 6 is an exploded view of the support of FIG. 5, FIG. 7 is a sectional view of the cover on plane VII-VII of FIG. 6, FIG. a perspective view of the support.

In Figure 1 is shown a vehicle 1 automobile comprising an internal combustion engine 2, provided with a turbocharger 3.

The automobile vehicle 1 comprises: a system 4 for lubricating the engine and the turbocharger 3, and a system 5 for engine cooling and a turbocharger cooling system 6 shown in FIG. 3.

The lubrication system 4 comprises a support 7, an oil filter 8 and a heat exchanger 9. The lubrication system 4 also includes an oil pump. The heat exchanger 9 makes it possible to cool the oil of the lubrication system 4 by heat exchange with the engine cooling system 5.

To perform the lubrication of the engine, the lubrication system 4 comprises elements (not shown): - a main ramp provided with injectors, the main boom spraying oil on crankshaft bearings; - A distribution ramp, also for spraying oil via injectors, on the cams-pads contacts.

The lubricating oil is first taken from a housing 11 located under the engine 2, with the oil pump 10, the oil is cooled in the heat exchanger 9 and then purified in the filter 8 to oil, before being injected into the engine 2, as previously explained. The oil thus injected into the engine 2 is recovered under the effect of gravity in the housing 11, to be used again. In parallel, a portion of the oil is sent to the turbocharger 3 via a turbocharging circuit 12. The oil of the lubrication system 4 thus makes it possible to lubricate the engine 2 and the turbocharger 3, which also contributes to their cooling.

The system 4 lubrication can not cool alone these elements as it should be done. This is the reason why the automobile vehicle 1 is equipped with a system 5 of engine cooling on the one hand, and a system 6 of turbocharging cooling on the other hand.

The turbocharger 3 supercharges the engine 2 in air, this to improve the combustion of the fuel-air mixture in cylinders 13 of the engine.

In a manner known per se and not shown, the turbocharger comprises a turbine, placed in the flow of the exhaust gas, connected to a compressor, placed in an engine air intake duct, the turbine and the engine. compressor being connected via a shaft.

The turbine, the shaft and the compressor are enclosed in a body 14. The shaft passes in a plain bearing (not shown), the latter being located between the shaft and the body 14. The sliding bearing must be cooled by an oil film occupying a tubular space between the body 14 and the shaft.

When the engine 2 is in operation, the turbocharger 3 is cooled by the lubrication system 4 which circulates oil therein.

However, when the engine 2 is stopped, the lubrication system 4 also stops, and the oil is not renewed, because the oil pump 10 is coupled to the engine 2.

After stopping the engine 2 and therefore the turbocharger 3, the turbine is at a significantly higher temperature than the sliding bearing. It then transmits heat to it via the shaft, which may damage it. In addition, the residual oil can be heated to excessive temperature and cause damage.

The engine cooling system 5 is known per se. It comprises, in a simplified and non-exhaustive manner, a motorcycle fan unit, an expansion vessel 16 containing the cooling fluid, a main pump 17 and the common heat exchanger 9 with the lubrication system 4. The main pump 17 circulates the cooling fluid in the engine cooling system 5, which allows in particular to cool the oil of the lubrication system 4, via the heat exchanger 9.

To cool the turbocharger 3 after stopping the engine 2, the cooling system 6 turbocharger replaces the system 4 lubrication. The turbocharger cooling system 6 comprises a coolant pump, hereinafter referred to as an electric pump 18, which circulates a cooling fluid in the turbocharger 3.

For the sake of compactness, several previously described elements are mounted on the support 7. Thus, the electric pump 18 (and preferably the heat exchanger 9 and / or the oil filter 8) are mounted on the support 7 The support 7 is shown in dashed lines in FIG.

In order to cool the turbocharger 3 after stopping the engine 2, the electric pump 18 is not coupled to the engine 2. It is powered and controlled independently, by an electrical system and control of the engine. 1 car vehicle. The electric pump 18 comprises for this purpose an electrical connector against 19, adapted to be connected to an electrical connector 20 from the electrical system and control of the vehicle 1 automobile.

The cooling of the turbocharger 3 is optimal when a pump is dedicated to it. For this purpose, the electric pump 18 comprises a single inlet 21 and a single outlet 22 through which the cooling fluid enters and leaves respectively. In the embodiment shown in the figures, the single inlet 21 is connected directly to a water outlet 23 of the heat exchanger 9. It is possible, however, that the electric pump 18 draws the cooling fluid at another location of the support 7, for example before the fluid enters the heat exchanger 9.

The single output 22 of the electric pump 18 is connected directly to the turbocharger 3 by a cooling pipe 24, as shown in FIG. 4. The turbocharger 3 is therefore supplied with cooling fluid when the engine 2 is at the same time. stop, thanks to the electric pump 18 dedicated to it.

When the cooling fluid leaves the turbocharger 3, it is returned to the engine cooling system 5 by a cooling return hose 25. In the diagram of Figure 3, the coolant is returned just after the heat exchanger 9. However, the return of the coolant may be at another location in the engine cooling system.

The material of the support 7 is advantageously an aluminum alloy. This is for example formed by molding, in a mold in which is injected aluminum under pressure.

The support 7 has a side face 26 on which is mounted the heat exchanger 9, and has an end 27 adapted to receive the oil filter 8.

When the engine 2 is in operation, the heat exchanger 9 cooled the oil system 4 lubrication without the assistance of the electric pump 18. Indeed, the electric pump 18 only operates when the engine 2 is stopped to cool the turbocharger 3. When the engine 2 is running, it is the main pump 17 of the engine cooling system 5 which circulates the fluid of the engine. cooling in the heat exchanger 9, thereby cooling the lubricating oil of the engine 2. When the engine 2 is running, the coolant does not rush into the electric pump 18 dedicated to the turbocharger 3, the latter is not therefore not supplied with cooling fluid, but only with oil by the turbocharging circuit 12, shown schematically in FIG. 3.

Advantageously, a three-way valve (not shown) can be positioned at a branch 28 to the turbocharger cooling system 6 and the engine cooling system 5. Thus, when the engine 2 is running, the three-way valve prevents the cooling fluid from entering the turbocharger cooling system 6, and allows the passage of the fluid in the engine cooling system 5, and vice versa when the engine 2 is at the same time. stop.

The support 7 comprises a plurality of orifices 29 for fixing. These fixing holes 29 allow to fix it to a dedicated area (not shown) of the vehicle 1 automobile with fixing screws (not shown).

The electric pump 18 comprises fastening means (not shown) for securing it to the support 7. Advantageously, the electric pump 18 is fixed on the support 7 by means of screws.

The lubricating system 4 oil arrives in the support 7 by a lubricant inlet 30, visible in Figure 8. The support 7 includes pipes (not visible in the figures), which allow the different fluids to flow in this one. A first pipe allows the oil to pass through the support 7 from the lubricant inlet to the heat exchanger 9. Once the oil has cooled in the heat exchanger 9, the heat exchanger 9 impresses a second pipe, towards the oil filter 8. Once filtered, the oil is conveyed, via a third pipe, to a lubricant outlet 31, visible in FIG. 8. In parallel, the cooling fluid of the engine cooling system 5 enters the support 7, via an inlet 32 8, the cooling fluid joins the heat exchanger 9 through a fourth pipe and then exits through a fifth pipe to a cooling outlet. The branch 28 is in the support 7, it is here that the cooling system 6 turbocharger draws the cooling fluid, when the engine 2 is stopped.

In another embodiment shown in Figures 5 and 6, the electric pump 18 is covered by a cover 34 comprising fixing means to the support. The fastening means may be of different shapes. In FIGS. 5 to 7, these are in the form of lugs 35 to be clipped into attachment zones (not shown), provided for this purpose on the support 7. Alternatively, not shown, the cover 34 may also be fixed on the support 7 by screws.

The cover 34 protects the electric pump 18.

In the embodiment shown in Figures 5 to 7, the cover 34 of the electric pump 18 comprises an outer electrical connector 36, projecting from the side of an outer face 37 thereof, and a connector 38 electrical interior, projecting from the side of an inner face 39. When the cover 34 is positioned so as to cover the electric pump 18, the electrical connector 38 inside faces and connects to the electrical connector 19 located on the electric pump 18. Thus, the electrical connector 20 of the electrical system and control of the vehicle 1 automobile, is not directly connected to the electric pump 18 but on the cover 34. The outer electrical connector 36 includes retaining clips 40, able to maintain the electrical connector 20 of the electrical and control system.

The cover 34 comprises a connection hose 41 projecting from the side of a side wall 42 thereof. The connection hose 41 is connected to the cooling pipe 24 of the turbocharger 3. The latter is therefore not directly connected to the single outlet 22 of the electric pump 18 but to the cover 34. The single outlet 22 of the electric pump 18 is connected to the connecting hose 41, inside the lid 34. The term "inside" denotes a space 43 located in the lid 34, and in which the electric pump 18 is housed.

In a variant, not shown in the figures, the electric pump 18 does not draw in the engine cooling system 5, but on the contrary in the lubrication system 4. Thus, when the engine 2 is stopped, the cooling of the turbocharger 3 is carried out by the oil of the lubrication system 4.

Such a cooling system of the turbocharger 3 offers the advantage of being optimal, since the electric pump 18 is entirely dedicated to it. Furthermore, the mounting of the oil filter 8, the exchanger and the electric pump 18 on the support provides a high compactness of the assembly. The number of parts used is reduced, as well as the pressure drops, this to the benefit of cooling the turbocharger.

Claims (10)

Motor vehicle engine (2) comprising: a motor lubrication system (4), provided with a support (7), at least one cooling system (6) provided with at least one pump ( 18), characterized in that the engine (2) comprises a turbocharger (3) adapted to supercharge the engine (2) with air, the coolant pump (18) comprises a single outlet (22), connected to the turbocharger (3) for cooling thereof. 2. Engine (2) according to claim 1, characterized in that the lubrication system (4) comprises at least one filter (8) oil mounted on the support (7). 3. Motor (2) according to claim 1 or claim 2, characterized in that the lubrication system (4) comprises at least one heat exchanger (9) mounted on the support (7). 4. Motor (2) according to claim 3, characterized in that a single inlet (21) of the coolant pump (18) between which the cooling fluid is positioned facing an outlet (23) water of the heat exchanger (9). 5. Motor (2) according to any one of the preceding claims, characterized in that the coolant pump (18) is electric, and comprises an electrical counter connector (19) intended to be connected to an electrical connector (20). ) an electrical system and control of the vehicle (1) automobile. 6. Motor (2) according to the preceding claim, characterized in that the support (7) comprises a cover (34) attached, the latter covering the pump (18) coolant projecting from the support (7). 7. Motor (2) according to claim 6, characterized in that the cover (34) comprises means (35) for fixing to the support (7). 8. Motor (2) according to any one of claims 6 or 7, characterized in that the cover (34) comprises a hose (41) connection projecting from the side of a side wall (42), the connection hose (41) being able to be connected to a cooling pipe (24) connecting the single outlet (22) to the turbocharger (3) for cooling thereof. 9. Motor (2) according to any one of claims 6 to 8, characterized in that the cover (34) comprises an outer electrical connector (36), projecting from the side of an outer face (37) of the therein, and an inner electrical connector (38) projecting from the side of an inner face (39), the outer electrical connector (36) being connected to an electrical connector (20) of an electrical and control system of the motor vehicle, the inner electrical connector (38) being connected to the electrical connector (19) of the coolant pump (18). 10. Motor (2) according to claim 9, characterized in that the outer electrical connector (36) comprises retaining clips (40), adapted to maintain the electrical connector (20) of the electrical and control system.