Sound-absorbing engine cover and V-engine with a sound-absorbing engine cover

Abstract

Sound-absorbing engine cover (10, 20, 30, 40) for covering an engine cavity (4) between two cylinder banks (2.1, 2.2) of a V-engine (1), comprising - a cover (12, 22, 32, 42) with a fan cutout (14, 24, 34, 44), and - at least one sound absorber (15, 25, 35, 45), characterized by a fan (16, 26, 36, 46) which is arranged at the fan recess and is designed to convey air from a side of the motor cover (10, 20, 30, 40) facing away from the motor cavity into the motor cavity (4).

Description

[0001] The invention relates to a sound-absorbing engine cover for at least partially covering an engine cavity between two cylinder banks of a V-engine, and to a V-engine for a passenger vehicle with such a sound-absorbing engine cover.

[0002] Internal combustion engines for motor vehicles—and by design, especially V-engines—often have cavities that form between engine components within the engine's housing. In V-engines, such a cavity (hereinafter also referred to as the V-space) is created between the two cylinder banks due to the arrangement of the cylinders at an angle γ to each other. Furthermore, in modern passenger vehicles, it is often a development goal to minimize the installation space required for certain components, including the engine. Therefore, the engine cavities described above are frequently used to house engine and / or engine peripheral components such as cylinder heads, an exhaust gas turbocharger, or exhaust aftertreatment components located near the engine.

[0003] Many common V-engines therefore have a multitude of engine and / or engine peripheral components in their engine cavity between the cylinder banks, some of which heat up during operation; for example, the turbocharger. Such components can often be cooled during driving by a suitable supply of cool ambient air to their surface due to the airflow. To ensure reliable cooling of the engine and its peripheral components even after the vehicle is switched off – when no airflow is available – common air-cooled engines for passenger vehicles are fitted with a front-mounted engine fan.

[0004] However, with the increasingly dense packing of engine and / or peripheral components into the engine cavity between the cylinder banks, it becomes progressively more difficult to direct sufficient cooling air to these components via the airflow from driving or the engine fan to ensure adequate cooling. Engine and / or peripheral components located further back in the engine cavity are particularly difficult to cool in this way. This problem is further exacerbated in a heated, parked vehicle by the sound-absorbing engine cover typically fitted above the engine cavity of modern V-engines. This engine cover, however, is necessary to keep the engine's noise emissions into the surrounding environment or the passenger compartment at a desired, low level.

[0005] Patent document JP 2004 211 658 A shows a heat insulation cover for an engine with V-cylinder banks, wherein a ventilation flap is arranged laterally on the cover to dissipate accumulated heat.

[0006] Patent document CN 2015 104 133 40 A shows a heat-radiating motor cover with a radiating recess for a bulldozer, wherein a fan is arranged in the radiating recess to dissipate accumulated heat.

[0007] Patent document JP H10-331636A shows a cover for a space between the cylinder banks of a V-engine, wherein a louver-like element is arranged in the cover which is designed to dissipate hot air.

[0008] One objective of the invention is therefore to provide sufficient cooling of V-motors under the strict installation space and noise emission requirements of modern passenger vehicles.

[0009] This problem is solved by a sound-absorbing engine cover having the features of claim 1 and by a V-engine according to the features of claim 5. Advantageous embodiments are the subject of the dependent claims.

[0010] According to a first aspect of the invention, a sound-absorbing engine cover is proposed for at least partially covering an engine cavity between two cylinder banks of a V-engine, preferably comprising a cover and at least one sound absorber. The sound-absorbing engine cover has a fan which, particularly when installed on the engine, is configured to draw air from a side of the engine cover facing away from the engine cavity into the engine cavity.

[0011] According to a second aspect of the invention, a V-engine for a passenger vehicle is proposed, comprising two cylinder banks and an engine cavity (also referred to as the V-space) arranged between the cylinder banks. The V-engine has a sound-absorbing engine cover according to an embodiment of the first aspect of the invention. This sound-absorbing engine cover at least partially, and preferably substantially completely, covers the engine cavity with respect to an installation orientation of the V-engine, at least at an upper boundary of the engine cavity. The cover can also be designed to partially or substantially completely delimit the engine cavity to the front and / or rear.

[0012] The invention is based, among other things, on the idea of ​​integrating a fan into the sound-absorbing engine cover, the blower of which can convey a cooling airflow to engine and / or engine peripheral components that, due to the dense packing of these components in the engine cavity, cannot be cooled or can only be cooled insufficiently by means of the frontally arranged engine cooler of the V-engine itself.

[0013] Depending on the application, the invention can utilize different mechanisms. Firstly, the fan of the sound-absorbing engine cover can direct cooling air to the engine and / or engine peripheral components requiring cooling, even if this is not possible or only partially possible with the V-engine's radiator due to space constraints. Secondly, the directed cooling airflow of the fan in the sound-absorbing engine cover can also redirect the cooling airflow of the engine fan. Thus, the fan installed according to the invention can not only utilize its own airflow for cooling, but also contribute to cooling the otherwise wasted cooling airflow of the engine fan.

[0014] In principle, the engine cover can, of course, also fulfill a technical function with regard to thermal insulation, for example, by incorporating heat shields. An aesthetic function of the engine cover can also be provided, for example, with refined surfaces on the side facing away from the engine cavity. The invention is described below using a configuration with a V-engine because, due to the angled arrangement of the two cylinder banks relative to each other, this engine inherently has a large engine cavity. Hereinafter, engine components may also be meant, although for the sake of readability, only engine peripheral components are mentioned.

[0015] In a typical longitudinally mounted V-engine, this engine cavity (also called the V-space) is delimited on both sides by the cylinder banks and preferably at least at the top by a sound-absorbing engine cover, particularly beyond a fan recess by its cover. The sound-absorbing engine cover, and especially its cover, is preferably arranged such that it delimits the engine cavity between the cylinder banks according to an imaginary outline of the engine. It can also be provided that the sound-absorbing engine cover, and especially its cover, at least partially delimits the engine cavity at a front end and / or a rear end of the cylinder banks.

[0016] Preferably, the cover of the sound-absorbing engine cover is attached to the cylinder banks of the V-engine, for example, by means of suitable fastening elements (e.g., clips or plug-in elements), and in particular forms a planar separation between the engine cavity and the environment of the V-engine. The sound absorber(s) of the engine cover are preferably arranged on the engine cavity side of the engine cover and connected to it. Suitable sound absorbers include, for example, fleece or foam mats or other cut elements made of suitable sound-absorbing materials, which are generally known to those skilled in the art.

[0017] The fan of the sound-absorbing engine cover preferably comprises a blower such as a fan, in particular an axial fan or a radial fan. Preferably, the fan, especially with its blower, is arranged on the cover in such a way that it can draw in cooling air on the side of the engine cover furthest from the engine cavity and, by means of the blower, can again discharge this air into the engine cavity at an accelerated rate, preferably along a cavity air guide axis.

[0018] The cover has a fan recess in which the fan is located. Preferably, the recess is spaced away from the edge of the cover so that it is completely surrounded by the cover in all directions. By providing a recess, the fan's placement is not limited to the outer edges of the engine cover, but can be positioned, for example, at a location where the supply of ambient cooling air can be particularly effective. For instance, the fan can be installed centrally with respect to the transverse direction of the engine and in the front half of the engine cover with respect to the longitudinal direction of the engine, in order to utilize the most unobstructed flow of cooling air possible.

[0019] A fan recess can be understood, for example, as a suitably shaped hole in a cover of the motor housing, preferably designed as a molded plastic part. The shape of the recess can preferably be adapted to the outer contour of the fan. Furthermore, suitable fastening elements such as clips, connectors, or mounting recesses can be provided in the area of ​​the fan recess and / or on the fan itself.

[0020] According to a preferred embodiment, the cover has an air guide. Such an air guide can advantageously be arranged on the ambient side of the fan, thus directing cooling air to the fan. However, the air guide can also advantageously be provided on the motor cavity side of the motor cover and, for example, redirect the airflow after it has passed through the fan into a desired cavity air guide axis.

[0021] In accordance with the invention, the air guidance axis within the motor cavity can be determined either by a main air guidance axis of the fan, in particular its fan itself, or by an air guidance on the motor cavity side.

[0022] According to a preferred embodiment, the fan and / or the air duct has an air guide axis on the engine cavity side, which forms an oblique angle with a perpendicular to a main extension plane of the cover, in particular between 15 and 75 degrees, preferably between 30 and 60 degrees. Such an oblique airflow ensures that, regardless of the external shape of the sound-absorbing engine cover (which may be specified by other requirements), the cooling airflow is directed towards specific engine peripheral components according to cooling requirements. For example, such an oblique positioning allows the fan to be positioned relatively far forward with respect to the engine's longitudinal direction, even if a peripheral component to be cooled is located further rearward with respect to the engine's longitudinal direction in the engine cavity between the cylinder banks.

[0023] Preferably, the air duct can include at least one air duct sound absorber to partially or completely compensate for the sound absorption capacity of the engine cover, which may be affected by the presence of the fan. Such an air duct sound absorber can be arranged either on the side of the fan facing away from the engine cavity or within the cavity itself.

[0024] To prevent the fan of the sound-absorbing engine cover from having to supply the entire airflow required for engine cooling, a preferred embodiment of the V-engine includes a front-mounted engine fan designed to draw air from the front of the V-engine into the engine cavity. As mentioned earlier, it is often not possible to adequately cool all engine peripheral components with this fan, for example, if a peripheral component mounted further forward deflects the airflow away from a peripheral component mounted further back, such as the V-engine's turbocharger.

[0025] To ensure adequate cooling of the peripheral component located further back, a preferred embodiment of the V-engine provides for at least one engine peripheral component to be arranged between the cylinder banks, towards which the airflow axis of the fan or the air duct in the engine cavity is at least substantially aligned. The airflow axis can either be aligned directly towards the corresponding engine peripheral component, for example, the turbocharger, or it can be aligned such that the cooling air from the engine cover fan deflects the cooling air from the V-engine's engine fan in such a way that the two airflows together cool the surface of the engine peripheral component.

[0026] In order to ensure an adequate supply of cooling air, according to a preferred embodiment the fan is installed further forward with respect to a longitudinal axis of the motor than the motor peripheral component.

[0027] According to a preferred embodiment, the V-engine has at least one temperature sensor arranged in the engine cavity, particularly on an engine peripheral component, and a control unit configured to influence the airflow rate of the fan, at least as a function of the temperature sensor readings. This allows cooling capacity to be switched on and / or off according to the prevailing cooling demand. Preferably, the control unit is also active when the vehicle is switched off, for example, to counteract the negative effects of heat buildup by switching on the fan of the sound-absorbing engine cover when the vehicle is off.

[0028] In accordance with the invention, the cover and at least one sound absorber of the sound-absorbing engine cover can also be formed together as a single, sound-absorbing component that delimits the engine cavity, for example made of a plastic material.

[0029] Advantageous embodiments of the various aspects of the invention are the subject of the dependent claims. Further features, advantages, and applications of the invention will become apparent from the following description in conjunction with the figures. These figures show, in part in a highly schematic representation, Fig. 1a-c a V-engine with a sound-absorbing engine cover according to an exemplary embodiment of the invention in a centrally cut side view, a front view and a top view of the V-engine; Fig. 2 a sound-absorbing motor cover according to an exemplary embodiment of the invention with an axial fan installed at an angle to the cover in a side sectional view; Fig. 3 a sound-absorbing motor cover according to an exemplary embodiment of the invention with an axial fan installed perpendicular to the cover in a side sectional view; Fig. 4 a sound-absorbing motor cover according to an exemplary embodiment of the invention with a radial fan in a side sectional view;

[0030] In the Fig. Figures 1a-c show a V-engine 1 for a passenger vehicle (not shown), which has two cylinder banks 2.1 and 2.2 positioned at an angle γ to each other. The V-engine 1 is highly schematic in these figures and is shown only with the components relevant to the embodiment.

[0031] Between cylinder banks 2.1 and 2.2, an engine cavity 4 designed as a V-space is arranged (compare Fig. 1 a). Several engine and engine peripheral components are arranged in the engine cavity 4, wherein in the Fig. 1 a and Fig. 1 b shows, by way of example and representation, a front engine peripheral component 6 and a rear engine peripheral component 8 - in this example a turbocharger. In Fig. 1 a the turbocharger 8 is shown with a dashed line because it is located behind component 6.

[0032] The motor cavity 4 is delimited upwards (with respect to a motor vertical axis z) and partially forwards (with respect to a motor longitudinal axis x) by means of a sound-absorbing motor cover 10. The motor cover 10 has a lid 12, for example, designed as a cast plastic part, for delimiting the motor cavity 4. A sound absorber 15, designed as a sound-absorbing mat, is suitably arranged on the side of the lid 12 facing the motor cavity. The sound absorber 15 can comprise a fleece element and / or a foam element. The motor cover 10 is suitably connected to the motor 1 at mounting points 11.1 and 11.2.

[0033] The engine cover 10 has a fan recess 14. A fan 16 is accommodated in the recess 14 and is arranged and designed to draw air from the side of the engine cover 10 facing away from the engine cavity into the engine cavity 4. In the illustrated embodiment, the recess 14 with the fan 16 is positioned approximately centrally with respect to a transverse dimension y and in the front half with respect to a longitudinal dimension of the V-engine 1. Other positions are, of course, conceivable depending on the specific conditions and requirements of the cooling airflow.

[0034] In the exemplary embodiment, the fan 16 is designed as an axial fan and is arranged in the recess 14 such that its air guidance axis L does not run along a perpendicular S to the plane of extension of the cover in the area of ​​the recess 14, but at an oblique angle α to it. In the exemplary embodiment, the angle α is approximately 30°.

[0035] The V-engine 1 also features a front-mounted engine fan 17, which is arranged along a longitudinal axis x of the engine in front of it. A temperature sensor 18 is also arranged in the engine cavity 4 on or near the turbocharger 8.

[0036] The motor cover fan 16, the motor fan 17, and the temperature sensor 18 are each connected to a control unit 19 via suitable control lines for power transmission and / or control. The control lines are in Fig. 1 b is represented by double dotted dash lines.

[0037] The functioning of the invention is described below with regard to the exemplary embodiment of the Fig. 1 ac based on the representation in Fig. 1 b explained.

[0038] The position of the recess 14 in the motor cover 10, in conjunction with the inclination of the air guide axis L at angle α, is chosen such that the fan 16 can direct air from outside the motor cavity 4 directly onto the rear motor peripheral component 8 (see dashed arrow through the fan 16). Whether cooling of the motor peripheral component 8 is required can be determined using the control unit 19 based on measured values ​​from the temperature sensor 18, for example, by comparing them with a desired temperature range. Depending on whether the control unit 19 detects a cooling requirement, it switches on the fan 16, if necessary with a variable airflow rate corresponding to the cooling requirement. In certain cases, the fan 16 provided in the motor cover 10 can render the operation of the motor fan 17 of the V-motor 1 unnecessary.For example, after switching off a heated vehicle, it may be sufficient to only switch on the smaller fan 16, thus conserving the vehicle battery.

[0039] However, the invention also allows the effect of the motor fan 17 to be adapted in such a way that it also benefits rear motor peripheral components 8 even when front motor peripheral components 6 deflect the airflow of the motor fan 17 away from the rear components 8. Fig. Figure 1b shows a dashed arrow running through the motor fan 17, which schematically illustrates that, due to the deflection of the airflow at component 6, the airflow passes, at least substantially, over component 8, which lies in the "shadow" of component 6. Therefore, component 8 cannot be adequately cooled. The airflow from the motor fan 17 does not reach component 8, or does not reach it sufficiently for adequate cooling.

[0040] In this case, by switching on the additional airflow from the fan 16 of the motor cover 10, the airflow from the motor fan 17 can be redirected so that at least part of the combined airflows (compare the course of the short dashed arrow line) hits the surface of the rear motor peripheral component 8 and provides sufficient cooling.

[0041] In the Fig. Figures 2 to 4 show different versions of sound-absorbing motor covers according to the invention, each with a different fan design. Each of these versions is illustrated in the exemplary embodiment according to the Fig. 1 AC usable.

[0042] Fig. Figure 2 shows a section of a sound-absorbing motor cover 20, which has a recess 24 for a fan 26. The fan 26 is designed as an axial fan with an axial blower 27, the circumferential walls 21 of which are fixedly received in a recess wall 23. The recess wall 23 runs parallel to the air guide axis L of the axial fan 26 and thus, like the air guide axis, at an angle α to a perpendicular S of a principal extension plane of the cover 22. The motor cover 20 also has a sound absorber 25, which is interrupted at the recess 24.

[0043] Fig. Figure 3 shows a section of a sound-absorbing engine cover 30, which has a recess 34 for a fan 36. The fan 36 is designed as an axial fan with an axial blower 37, the circumferential walls 31 of which are fixedly received in a recess wall 33. The recess wall 33 runs parallel to a vertical line S of a main extension plane of the cover 32 and transitions on the engine cavity side 4 into an air duct 38, the inner walls of which are parallel to an air duct axis L. The air duct axis L and the vertical line S are at an angle α to each other. The cooling air conveyed by the blower 37 is discharged into the engine interior 4 along the air duct axis L.

[0044] On the inner walls of the air duct 38, an air duct sound absorber 39, formed with a sound absorption mat, is arranged around the perimeter to compensate for the interruption of the sound absorber 35 at the recess 34.

[0045] Fig. Figure 4 shows a section of a sound-absorbing motor cover 40, which has a recess 44 for a fan 46. The fan 46 is designed as a radial fan with a radial blower 47, the circumferential walls 41 of which are fixedly received in a recess wall 43. The recess wall 43 runs parallel to a perpendicular S of a principal extension plane of the cover 42, the perpendicular S being parallel to the axis of rotation of the radial blower 47. On the motor cavity side 4, the recess wall 43 transitions into an air duct 48, the inner walls of which are parallel to an air duct axis L. The air duct axis L and the perpendicular S are at an angle α to each other.

[0046] The fan 46 according to Fig.4 additionally features an air inlet 50, in which air is drawn in parallel to a main extension plane of the cover 42 towards the radial fan 47. The cooling air conveyed by the radial fan 47 is then discharged along the air guide axis L into the engine compartment 4.

[0047] On the inner walls of the air duct 48, an air duct sound absorber 49 is arranged around the perimeter, and on the inner walls of the air supply 50, a sound absorption mat 51 is arranged around the perimeter, each to compensate for the interruption of the sound absorber 45 at the recess 44. REFERENCE MARK LIST 1 V-engine 2 cylinder banks 4 Engine cavity 6 front engine peripheral components 8 rear engine peripheral components (e.g. turbocharger) 10, 20, 30, 40 Sound-absorbing engine cover 11 assembly sites 12, 22, 32, 42 lids 14, 24, 34, 44 Exclusion 15, 25, 35, 45 sound absorbers 16, 26, 36, 46 Fans of the sound-absorbing motor cover 17 front engine fan 18 Temperature sensor 19 Control unit 21, 31, 41 Perimeter wall of the fan 23, 33, 43 Recess wall 27, 37 Axial blowers 38, 48 Air duct 39, 49, 51 Air duct sound absorber 47 radial blowers 50 Air supply 51 sound absorption mat S Perpendicular to the main extension plane of the lid L air guide shaft in the engine cavity α Angle between S and L γ angle between the cylinder banks x Motor longitudinal axis y Motor transverse axis z Motor vertical axis

Claims

[1] Sound absorption engine cover (10, 20, 30, 40) for covering an engine cavity (4) between two cylinder banks (2.1, 2.2) of a V-engine (1), comprising - a cover (12, 22, 32, 42) with a fan cutout (14, 24, 34, 44), and - at least one sound absorber (15, 25, 35, 45), characterized by a fan (16, 26, 36, 46) which is arranged at the fan recess and is configured to convey air from a side of the motor cover (10, 20, 30, 40) facing away from the motor cavity into the motor cavity (4). [2] Sound absorption engine cover (10, 20, 30, 40) according to claim 1, wherein the cover (12, 22, 32, 42) has an air guide (38, 48). [3] Sound absorption motor cover (10, 20, 30, 40) according to one of the preceding claims, wherein the fan (16, 26, 36, 46) and / or the air guide (38, 48) has an air guide axis (L) on the motor cavity side which has an oblique angle α with a perpendicular (S) of a principal extension plane of the cover. [4] Sound absorption engine cover (10, 20, 30, 40) according to claim 2 or 3, wherein the air guide (38, 48) has at least one air guide sound absorber (39, 49). [5] V-engine (1) for a passenger vehicle, comprising two cylinder banks (2.1, 2.2) and an engine cavity (4) arranged between the cylinder banks, characterized by a sound-absorbing engine cover (10, 20, 30, 40) according to one of the preceding claims, which at least partially covers the engine cavity (4) with respect to an installation orientation of the V-engine at least at an upper boundary of the engine cavity. [6] V-engine (1) according to claim 5, comprising a frontal engine fan (17) which is configured to convey air from a front environment of the V-engine (1) into the engine cavity (4). [7] V-engine (1) according to one of claims 5 or 6, wherein at least one engine or engine peripheral component (8) is arranged between the cylinder banks (2.1, 2.2), towards which the air guide axis (L) of the fan (16) is at least substantially aligned. [8] V-motor (1) according to any one of claims 5 to 7, wherein the fan is installed further forward with respect to a motor longitudinal axis (x) than the motor or motor peripheral component (8). [9] V-motor (1) according to one of claims 5 to 8, comprising at least one temperature sensor (18) arranged in the motor cavity (4), in particular on a motor peripheral component (8), and a control unit (19) which is configured to influence an air delivery rate of the fan (16, 26, 36, 46) at least as a function of measured values ​​of the temperature sensor (18).

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