Fastening device for fastening heat exchanger to cylinder head of internal combustion engine

Abstract

The invention relates to a fastening device (1) for fastening a heat exchanger (3) to a cylinder head of an internal combustion engine, the fastening device (1) comprising an opening (12) through which air from the heat exchanger (3) and directed towards an air inlet arranged in the cylinder head can pass, the fastening device (1) being characterised in that the opening (12) is formed in the opening (12), it comprises at least one retention zone (14) and means for holding a liquid present in the retention zone (14).

Description

[0001] The present invention relates to the field of automotive industry, more particularly to a fastening device for fastening a heat exchanger to a cylinder head of an internal combustion engine.

[0002] In a vehicle equipped with a heat engine or an internal combustion engine, the engine comprises an intake port for injecting air into the combustion chamber of the engine. This intake port is located on an intake face of the heat engine on which the device for supplying fresh air is mounted. On the other side of this intake face of the engine, there is an exhaust face to which the device of the exhaust line is attached for delivering combustion gases towards the outside of the engine and a depollution system. The two faces extend longitudinally along the engine, that is to say, in the length direction of the engine.

[0003] In order to reduce pollutant emissions, such a heat engine is generally equipped with a line for recirculating combustion gases and gases resulting from the oil vapors emitted by the engine. The combustion gases are generally redirected towards the intake port of the engine after being compressed upstream of the intake manifold, in order to be mixed with fresh air coming from the outside of the vehicle before being re-injected into the intake circuit of the engine.

[0004] The recirculated gases comprise high pressure gases taken directly from the outlet of the exhaust face of the engine or from the exhaust manifold attached to the engine and further low pressure gases taken downstream, in particular at the level of the depollution device, such as a catalytic converter or a nitrogen oxide trap.

[0005] In order to cool the air and the recirculated gases injected into the intake circuit of the engine as much as possible, a water-air heat exchanger is generally used upstream of this intake circuit. This makes it possible to increase the efficiency of the engine. The heat exchanger is generally located between the throttle body and the cylinder head of the engine and as close as possible to the cylinder head of the engine so that the air does not have time to warm up. The heat exchanger, made of metal, is generally equipped with one or more plastic devices to allow the heat exchanger to be fastened to the components located upstream and downstream of the heat exchanger. In particular, a first device, generally referred to as the intake tank of the heat exchanger, is connected to the throttle body, while a second device, generally referred to as the cylinder head fastening tank, allows the heat exchanger to be connected to the cylinder head of the engine through the plenum chamber of the cylinder head.

[0006] According to the architecture of the powertrain comprising the heat engine and its arrangement within the vehicle, liquid retention zones can form between the heat exchanger and the plenum chamber of the cylinder head of the engine when the vehicle is parked, in particular on a slope. In these retention zones, condensates can accumulate, which can be oil condensates, coolant condensates or water. The latter two condensates are problematic because if they reach the pistons of the engine, a high concentration of water can accumulate in the combustion chamber when the cylinder block is located below the cylinder head and damage the engine.

[0007] To prevent this engine degradation, it is necessary to find a powertrain architecture that does not allow the formation of such fluid stagnation zones. However, this architecture is difficult to achieve when the cylinder block is located below the cylinder head, because it is impossible to guarantee the minimum parking slope of the vehicle.

[0008] The present invention aims to at least partially address the shortcomings of the prior art by providing a fastening device for securing a heat exchanger to the cylinder head of an internal combustion engine, an arrangement including an internal combustion engine, a heat exchanger and such fastening device, and an assembly including a heat exchanger, an intake box and such fastening device (which retains condensate and directs the condensate to an area smaller than the combustion chamber of the engine).

[0009] Therefore, the present invention provides a fastening device for fastening a heat exchanger to the cylinder head of an internal combustion engine, the fastening device including an opening through which air from the heat exchanger and directed toward an intake port arranged in the cylinder head can pass, the fastening device being characterized in that it includes at least one stagnation zone and means for retaining liquid present in the stagnation zone.

[0010] The fastening device (also called a fastening box) according to the invention can thus retain liquid formed by condensation. The retaining device particularly allows condensate to freeze in very cold weather because the condensed liquid in the stagnation zone is held there, at least until a certain amount of liquid is retained in that zone. Furthermore, when the vehicle is restarted and in a position where the stagnation zone would become empty without the retaining device of the fastening device, the liquid is at least partially retained in the stagnation zone, thereby preventing deterioration of the vehicle engine connected to the fastening device.

[0011] For example, the retaining device includes a rib that extends from the lower wall of the opening. The fastening device is preferably made of molded plastic, for example, the rib is molded simultaneously with the fastening device according to the invention.

[0012] The fastening device according to the invention generally has the shape of a frame, the frame comprising four walls defining an opening of the fastening device, air entering the opening through a first surface of the fastening device and exiting the opening through a second surface of the fastening device opposite to the first surface, the first and second surfaces being substantially orthogonal to the four walls. "Substantially orthogonal" means orthogonal within 30 degrees.

[0013] For example, these first and second faces are designed to be arranged parallel to the main extension direction of the camshaft of the internal combustion engine. The first face includes fastening devices to the heat exchanger, such as flanges that allow the heat exchanger fins to close on the flanges, and the second face includes fastening devices to the cylinder head (such as screw passage holes).

[0014] The lower wall of an opening is one of the four walls of the opening that should be substantially parallel to the road when a vehicle is parked or driving on the road. "Substantially parallel" means that the angle between the lower wall and the road is zero or non-zero, but less than 30 degrees.

[0015] In a preferred embodiment, the fastening device according to the invention includes a passage for gas generated by oil vapor from a gas distribution pipe arranged in the cylinder head, the passage including at least one gas outlet hole formed in the lower wall and a connection to the distribution pipe, the outlet hole being arranged outside the stagnation area.

[0016] The gas distribution channel generated by oil vapor in the cylinder head is also called a "blow-by" channel. Therefore, the channel arranged in the fastening device according to the invention allows gas generated by oil vapor in the cylinder head to exit through an outlet hole, reach the opening of the fastening device, and be re-injected into the engine intake. By being arranged outside the stagnation zone, liquid contained in the stagnation zone cannot be directly discharged into the gas channel generated by oil vapor, and thus cannot be discharged into the distribution channel arranged in the cylinder head. Otherwise, the engine oil may be contaminated by water or other pollutants, which is harmful to the engine.

[0017] For example, a rib extends from a first surface of the fastening device toward a second surface of the fastening device, and an outlet hole is arranged between the rib and the cylinder head. For example, a channel is formed on the second surface below the lower wall, and the cylinder head closes the channel but not the outlet hole. When the cylinder head is fastened to the fastening device according to the invention, a distribution pipe leads to the channel.

[0018] According to a preferred feature of the fastening device of the invention, the rib includes at least one discharge zone for liquid overflow from the stagnation zone. This allows for the control of the discharge of excess liquid present in the stagnation zone, particularly by promoting its gradual evaporation. The discharge zone also allows the excess liquid to be directed toward an area of ​​the fastening device or cylinder head smaller than the engine's intake port.

[0019] Specifically, the fastening device according to the invention preferably includes a guiding device capable of directing liquid leaving the discharge zone toward the outlet orifice. Thus, excess liquid is directed to the gas passage where oil vapor is generated, and therefore to the distribution pipe leading to the decanter. This prevents condensate from entering the engine's combustion chamber.

[0020] In one embodiment of the invention, the outlet orifice is adjacent to the rib at the level of the discharge zone, and the guide device forms the edge of the outlet orifice.

[0021] According to another embodiment, the guiding device forms a pipe extending from the discharge zone to the outlet orifice.

[0022] For example, the vent zone is formed by a lower region within a rib. For example, the rib includes a first height at the level of the vent zone and a second height above the first height over the remaining periphery of the rib. These heights are, of course, non-zero. For example, the first and second heights are optimized to allow maximum fluid retention when the vehicle is parked and fluid evaporation when driving. Alternatively, the vent zone may be formed by orifices within the rib.

[0023] Preferably, the fastening device includes a plurality of outlet holes distributed along a rib, the rib including as many discharge zones as the outlet holes, each outlet hole adjacent to a discharge zone and defined by a guiding device capable of directing liquid leaving the discharge zone back to the outlet hole. This distribution is regular in order to create a uniform distribution of oil from the blow-by chamber at the level of the engine's intake boost chamber.

[0024] For example, in the case where the rib defines a general rectangular shape, the fastening device according to the invention includes two outlet holes that are symmetrical with respect to the plane of symmetry of the general rectangular shape, orthogonal to the lower wall, and spaced apart by at least half of the maximum dimension of the general rectangular shape.

[0025] The present invention also relates to an arrangement comprising an internal combustion engine, a heat exchanger, and a fastening device according to the invention, which is sealed to the cylinder head of the internal combustion engine on one hand and sealed to the heat exchanger on the other.

[0026] Finally, the invention also relates to a component comprising a heat exchanger, an air inlet box, and a fastening device according to the invention, the air inlet box being connectable to an air inlet of the heat exchanger and the fastening device being connectable to an air outlet of the heat exchanger.

[0027] On the one hand, other features and advantages of the invention will become apparent from the following description, and on the other hand, will also become apparent from the various exemplary embodiments given with reference to the accompanying drawings for illustrative and non-limiting purposes, wherein:

[0028] Figure 1 This is a perspective view of the structure of the fastening device according to the present invention, which includes an internal combustion engine, a heat exchanger, and the present invention, according to one embodiment of the present invention.

[0029] Figure 2 This is a transverse perspective view of an assembly according to the invention, comprising a heat exchanger, an air inlet box connected to one side of the heat exchanger, and a fastening device connected to the other side of the heat exchanger, in this embodiment of the invention.

[0030] Figure 3 yes Figure 2 Top-view 3D view of the components;

[0031] Figure 4 yesFigure 2 A cross-sectional view of the fastening device, the cross-section being parallel to one side wall of the fastening device;

[0032] Figure 5 yes Figure 2 A view of one side of the fastening device, suitable for connection to Figure 1 The cylinder head of an internal combustion engine arranged as shown;

[0033] Figure 6 yes Figure 2 Fastening equipment and Figure 5 A three-dimensional diagram showing the faces facing each other; and

[0034] Figure 7 yes Figure 5 An enlarged view of the area of ​​the fastening device shown.

[0035] according to Figure 1 The embodiment of the present invention shown includes a structure according to the present invention. Figure 1 The diagram shows only the internal combustion engine of the cylinder head 2, the heat exchanger 3, and the fastening device 1 according to the invention, which is sealed to the air outlet of the heat exchanger 3 on one hand and sealed to the intake surface arranged in the cylinder head 2 of the internal combustion engine on the other. The intake surface opens to the air intake port in the cylinder head 2 to allow air to be delivered to the combustion chamber of the engine. The intake surface extends substantially parallel to the longitudinal direction Y (which itself is parallel to the axis of rotation of the engine's camshaft) and substantially parallel to the vertical direction Z (which is orthogonal to the longitudinal direction Y and the lateral direction X). The lateral direction X extends orthogonal to the vertical direction Z and the longitudinal direction Y, and is substantially parallel to the airflow direction through the intake surface of the cylinder head 2.

[0036] Air arriving at the intake port in the cylinder head 2 via the heat exchanger 3 and then the fastening device 1 comes from the intake duct 7, which is connected to the throttle body 5 via a connector 6. The throttle body 5 includes a throttle valve controlled by a control unit. The throttle valve allows adjustment of the air pressure at the inlet of the intake box 4, which is connected to the valve, allowing air leaving the throttle valve to be directed to the intake port of the heat exchanger 3.

[0037] Therefore, the air inlet box 4 includes an air outlet surface connected to the air inlet of the heat exchanger 3, which has a first air inlet surface 30 connected to the fastening device 1 (particularly in... Figure 4 The air outlet of the winning bidder, and the second air outlet surface 32 in the fastening device 1 (also in Figure 4 (Pointed out) The intake surface is connected to the cylinder head 2. All these surfaces are substantially parallel to each other and therefore parallel to the longitudinal direction Y and the vertical direction Z.

[0038] like Figure 2As shown, the fastening device 1 typically has the shape of a frame, which includes four walls that define an opening 12 of the fastening device 1. Air enters the opening 12 through a first surface 30 of the fastening device 1 and exits the opening 12 through a second surface 32 of the fastening device 1 opposite to the first surface 30. The first surface 30 and the second surface 32 are substantially orthogonal to the four walls.

[0039] In this embodiment of the invention, the heat exchanger 3 is metallic (e.g., made of aluminum) and includes a metal tab folded onto a flange of the fastening device 1 for attachment thereto, the flange defining a first air inlet surface 30 of the fastening device 1. The heat exchanger 3 also includes a metal tab folded onto a flange of the air inlet box 4 for attachment thereto.

[0040] The fastening device 1 includes a lower wall 16 that is substantially parallel to the longitudinal direction Y and the lateral direction X. Depending on the inclination of the vehicle when parked (especially on a slope), the lower wall 16 may include a retention area 14 for oil condensate or water condensate.

[0041] To prevent these liquids from flowing directly into the engine intake when the vehicle is restarted and returns to a less inclined position than when it was parked, the fastening device 1 according to the invention includes means for retaining these liquids in the retention area 14. In this embodiment of the invention, these retaining means are... Figure 3 Rib 18 is shown. In this embodiment, the fastening device 1 is made of molded synthetic material, and rib 18 is formed by molding.

[0042] The rib 18 defines a stagnation zone 14 extending below the heat exchanger 3 to retain moisture at the outlet of the heat exchanger 3 as it condenses and flows to the lower wall 16. Therefore, the rib 18 includes two arms 181, 182 that are substantially parallel to the transverse direction X and thus parallel to the airflow direction. Each of these arms 181, 182 is connected at one end by a branch 183 that is substantially parallel to the longitudinal direction Y, and this branch 183 is closer to the second surface 32 of the device than the other ends of these arms 181, 182. These other ends are each located at different ends of the junction between the lower wall 16 and the outlet surface of the heat exchanger 3 and / or between different horizontal variations of the lower wall 16.

[0043] In fact, such as Figure 4 As shown, the lower wall 16 has a receiving surface 162 for the heat exchanger 3, which is located near the first surface 30 and inclined relative to the rest of the lower wall 16 164. Therefore, the arms 181, 182 of the ribs 18 start from the outside of the receiving surface 162, and the rest of the lower wall 16 164 is located between the two arms 181, 182 and the branches 183 of the ribs 18 that form the stagnation zone 14 at the outlet of the heat exchanger 3.

[0044] likeFigure 5 Specifically, the fastening device 1 includes a channel 20 (molded as a recess on its second surface 32) for gas generated by oil vapor from a gas distribution pipe arranged in the cylinder head 2 and opened through a dedicated opening 8. The channel 20 is defined by an edge 31 of a lower wall 16 extending on the second surface 32, a flange also extending on the second surface 32 for receiving a gasket 26, and outlet holes 22, 24 also arranged on the second surface 32. These outlet holes 22, 24 allow gas generated by oil vapor from the engine cylinder head 2 to exit into the opening 12 of the fastening device 1.

[0045] Therefore, when the intake surface of the cylinder head 2 is fixed to the second surface 32 of the fastening device 1 (particularly through the screws passing through the screw channels 28 arranged around the periphery of the second surface 32), the cylinder head 2 closes the passage 20, while still allowing gas generated by oil vapor leaving the cylinder head 2 through the dedicated opening 8 to circulate through the passage 20. The gas generated by the oil vapor then reaches the opening 12 of the fastening device 1 through the outlet holes 22, 24 and can enter the engine's boost chamber. The sealing gasket 26 prevents air or gas generated by the oil vapor from leaking to the outside of the fastening device 1 or the cylinder head 2.

[0046] The outlet holes 22 and 24 are arranged in the lower wall 16, but outside the retention area 14. Therefore, the condensate held in the retention area 14 by the rib 18 cannot flow directly into the so-called "blow-by" chamber of the cylinder head.

[0047] However, rib 18 includes a discharge zone 34 for liquid overflowing from retention zone 14 (particularly in...). Figure 4 and Figure 6 (Selected from the list). These discharge zones 34 allow excess liquid to drain gradually without entering the intake duct of cylinder head 12. In particular, they are located near outlet holes 22, 24 to allow excess liquid to fall into passage 20, thereby preventing excess liquid from entering the engine's combustion chamber.

[0048] like Figure 6 As shown, these emission zones 34 are formed by the height h1 of ribs 18, and the height h1 of the ribs 18 at each emission zone 34 is lower than the height h2 of the ribs on the outer side of these emission zones 34.

[0049] Figure 7 An enlarged view of the second surface 32 at the level of the outlet orifice 22 is shown to clarify the corresponding arrangement of the discharge zone 34 and the outlet orifices 22, 24. The outlet orifice 22 is adjacent to the rib 18 at the level of the discharge zone 34. In this embodiment, a guiding device formed by the edge 36 on each side of the outlet orifice 22 guides excess liquid passing through the rib 18 in the discharge zone toward the outlet orifice 22.

[0050] Since the discharge zone 34 is defined by a portion of the rib 18 having a height h1 that is lower than the height h2, the edges 36 each extend in the lateral direction X from different ends of the portion of the rib defining the discharge zone 34 to the second surface 32 (that is, to the surface for contact with the cylinder head 12).

[0051] The outlet orifices 22 and 24 and the associated exhaust zone 34 are symmetrical with respect to the plane of symmetry of the rib 18 extending in the lateral direction X and the vertical direction Z, and are regularly distributed along the rib 18. The outlet orifices 22 and 24 are clearly spaced apart from each other in order to uniformly distribute the gas generated by the oil vapor entering the engine's boost chamber.

[0052] Of course, the present invention is not limited to the examples described above, and many modifications can be made to these examples without departing from the scope of the invention. In particular, for example, two or more outlet holes may be arranged on the lower wall 16, or only one outlet hole may be arranged. Furthermore, in an alternative embodiment of the invention, the outlet holes 22, 24 are offset relative to the discharge zone 34, and the guiding device is a rib that forms an actual conduit between the discharge zone 34 and the outlet holes 22, 24. The term "offset" is understood to mean that the discharge zone 34 is positioned substantially collinear with the outlet holes 22, 24, particularly above the outlet holes 22, 24, such that the discharge zone is connected to the outlet hole via a conduit formed by the guiding device 36.

Claims

1. A fastening device (1) for fastening a heat exchanger (3) to a cylinder head (2) of an internal combustion engine, the fastening device (1) comprising an opening (12) through which air from the heat exchanger (3) and directed toward an intake port arranged in the cylinder head (2) can pass. The fastening device (1) is characterized in that it includes at least one retention area (14) and a holding device for retaining liquid present in the retention area (14).

2. The fastening device (1) according to claim 1, wherein, The retaining device includes a rib (18) that extends from the lower wall (16) of the opening (12).

3. The fastening device (1) according to claim 1 or 2, wherein, The fastening device (1) includes a passage (20) for gas generated by oil vapor from a gas distribution pipe arranged in the cylinder head (2). The passage (20) includes at least one gas outlet hole (22, 24) formed in the lower wall (16) and a connection to the distribution pipe. The outlet hole (22, 24) is arranged outside the stagnation area (14).

4. The fastening device (1) according to claim 3, wherein, The rib (18) includes at least one discharge zone (34) for liquid to overflow from the retention zone (14).

5. The fastening device (1) according to claim 4, wherein, The rib (18) includes a first height (h1) at the level of the discharge area (34) and a second height (h2) above the first height (h1) on the rest of the periphery of the rib.

6. The fastening device (1) according to claim 4 or 5, comprising a guiding device (36) capable of guiding liquid leaving the discharge zone (34) toward the outlet orifice (22, 24).

7. The fastening device (1) according to claim 6, wherein, The guiding device (36) forms a conduit extending from the discharge zone (34) to the outlet holes (22, 24).

8. The fastening device (1) according to claim 6, wherein, The outlet holes (22, 24) are adjacent to the rib (18) at the level of the discharge zone (34), and the guide device (36) forms the edge of the outlet holes (22, 24).

9. The fastening device (1) according to any one of claims 6 to 8, wherein, The fastening device (1) includes a plurality of outlet holes (22, 24) distributed along the rib (18), the rib (18) including as many discharge zones (34) as the outlet holes (22, 24), each outlet hole (22, 24) being adjacent to a discharge zone (34) and defined by a guide device (36) capable of guiding liquid leaving the discharge zone (34) to the outlet hole (22, 24).

10. A structure comprising an internal combustion engine, a heat exchanger (3) and a fastening device (1) according to any one of claims 1 to 9, the fastening device (1) being sealed to the cylinder head (2) of the internal combustion engine on one hand and sealed to the heat exchanger (3) on the other hand.

11. A component comprising a heat exchanger (3), an air inlet box (4), and a fastening device (1) according to any one of claims 1 to 9, wherein the air inlet box (4) is connectable to an air inlet of the heat exchanger (3), and the fastening device (1) is connectable to an air outlet of the heat exchanger (3).

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