GB2347399A - Engine encapsulation including fluid passages - Google Patents

Abstract

An internal combustion engine in a motor vehicle is at least partially enclosed by encapsulation (16) made of thermoplastics material. One wall (22) of the encapsulation (16) is in the form of a block of material internally formed with passageways for transporting water between the radiator (32) and the cooling system of the engine (10) and/or for transporting air from an inlet (54) to the turbo (38) and from the turbo to an intercooler (34) and thence to the engine. The passageways formed internally in the wall 22 (22) are connected to the engine (10) and the turbo (38) by respective hoses (44,50,52). The encapsulation (16) is mounted on the engine (10) and the radiator (32) and the intercooler (34) are mounted on the encapsulation (16). The resultant assembly is supported in a vibration-damped manner by engine mounts acting between the body of the vehicle and support arms (e.g. 30) rigidly attached to the engine and extending externally of the encapsulation (16).

Description

IMPROVEMENTS IN OR RELATING TO ENGINES The invention relates to engines, to the transporting of fluid inputs thereto and therefrom, and to sound reducing arrangements therefor. The invention is primarily applicable to internal combustion engines, such as engines for vehicles for example.

According to the invention, there is provided an arrangement for transporting a fluid between an engine and a location externally of the engine, comprising a block of material in which is internally formed a passageway for the fluid.

According to the invention, there is further provided an arrangement for at least partially enclosing an internal combustion engine in a vehicle, comprising wall parts forming parts of an encapsulation and arranged to be placed around the outside of the engine and around at least some of its ancillary components but not around heat-exchanger means for the engine, one of the wall parts comprising a block of material in which is internally formed a plurality of passageways each extending between openings in respective faces of the block of material, one opening of one of the passageways being adapted for connection to heat-exchanger means on the opposite side of the block of material to the engine and the other opening of that passageway being adapted for connection to the engine or an ancillary component therefor.

Arrangements embodying the invention for use in transporting fluid inputs to and from internal combustion engines and for at least partially encapsulating engines for sound reduction purposes will now be described, by way of example only, with reference to the accompanying diagrammatic drawings in which: Figure 1 is a perspective view from one side and above of an engine encapsulated by one of the arrangements ; Figure 2 is a perspective view corresponding to Figure 1 but viewed from a different angle; Figure 3 is a perspective view corresponding to part of Figures 1 and 2 but from another angle; Figure 4 is a plan view corresponding in a general sense to the arrangement shown in Figures 1 to 3; Figure 5 is a section taken on the line V-V of Figure 4 but showing a modifie form of the arrangement; Figure 6 is a partial section through the arrangement shown in the preceding Figures and illustrating an engine mount; Figure 7 is a plan view of another of the arrangements; Figure 8 is a plan view of the arrangement of Figure 7 when connected to the engine and its ancillary components and showing connections to the engine cooling system; Figure 9 is an end view in the direction of the arrow IX of Figure 8; Figure 10 corresponds to Figure 8 but shows connections to the engine turbo; Figure 11 is a partial section on the line XI-XI of Figure 8; Figure 12 is a plan view corresponding to Figure 8 or 10 but showing a modification; and Figure 13 shows how the arrangement of Figures 8-11 can be expanded to encapsulate the engine.

Referring firstly to Figures 1 and 2, an internal combustion engine 10 for a vehicle is shown. The engine is mounted transversely at the front of the vehicle, and the drive shafts 12 (Figure 1) and 14 (Figure 2) are shown (the Figures show various attitudes which the drive shafts can assume according to relative movement between the front wheels of the vehicle and the body of the vehicle). In accordance with the embodiment being described, the engine 10 is enclosed within an encapsulation shown generally at 16. The encapsulation 16 may be made of suitable plastics material (as will be described in more detail below); different parts of the encapsulation 16 may be made of different types of material.

As shown in Figures 1 and 2, the encapsulation comprises a side wall 18 extending across one end of the engine 10 and integral (in this example) with a front wall 20 extending across the front of the engine (the term"front"of the engine refers to the part of the engine facing the front of the vehicle). At the end of the engine opposite to the wall 18 of the encapsulation, the encapsulation includes a further wall 22. At the rear of the engine, the encapsulation comprises a wall 24 (Figure 3). The encapsulation extends at least partially under the engine as will be described. Finally, the upper part of the encapsulation is closed off by a cover or lid of which part is shown at 26 in Figure 2. The lid, or part of it, may be removable or hingeable relative to the remainder of the enclosure 16 to permit access to the engine and its ancillary components for inspection and servicing purposes.

As shown in Figures 1 and 2, a rigid engine support arm 30 is rigidly attached to the engine and extends sideways and externally of the encapsulation 16; the upper part of the encapsulation extends over the engine underneath the engine support arm 30 and seals around the latter. The engine support arm 30 is attached to the vehicle body or chassis by means of a conventional vibration-damping engine mount. In similar fashion, at least two other points on the engine would be supported from the vehicle body by means of similar conventional engine mounts, support arms being rigidly attached to the engine for this purpose and extending externally and sealingly of the encapsulation 16. In a manner to be explained in more detail below, the encapsulation 16 is secured to the engine so that it, like the engine, is supported from the vehicle body by the engine mounts.

Figures 1 and 2 show the engine radiator 32 which is mounted externally of the encapsulation 16 in a manner to be explained in more detail. The radiator has water inlet and outlet connections and these are connected to the cooling system of the engine, again in a manner to be explained in more detail. Figures 1 and 2 also show an intercooler 34 mounted alongside the radiator 32, and this is connected to the engine turbo, again in a manner to be explained. Ambient air passing through the radiator 32 and the intercooler 34 passes under the engine and externally of the encapsulation 16 as indicated generally by the arrows A. To facilitate this, the radiator 32 and the intercooler 34 are advantageously mounted at an inclined angle, as shown in Figures 1 and 2, though this is not essential.

In this way, therefore, the engine and most of its ancillary components are enclosed within the encapsulation 16, which enables a substantial reduction in externally radiated engine noise.

Figure 3 shows the gearbox 36 which is positioned externally of the encapsulation 16, the latter being sealed around the casing of the gearbox. Figure 3 also shows the turbo 38. This is advantageously mounted externally of the encapsulation 16 because of the high temperature which it will normally reach. As shown in Figure 3, the exhaust manifold 40 of the engine protrudes through the rear face 24 of the encapsulation 16, as does the inlet manifold 42. Suitable sealing is provided around these manifolds where they protrude through the wall 24. The exhaust manifold is connected to the turbo 38 by a connection 44 for driving the turbo in the normal way.

In accordance with a feature of the embodiments being described, fluids being transported to and from the engine (for example, water for the cooling system and air travelling between the turbo 38 and the intercooler 34) are transported by means of passageways formed internally within the material of the end wall 22 of the encapsulation 16, this wall being for this purpose generally thicker than the other walls of the encapsulation. These passageways have openings at each end. As shown in Figures 1, 2 and 3, flexible hoses 44 each connect one end of these internal passageways to the cooling system of the engine. Although (as already explained) the encapsulation 16 is mounted on the engine 10 and moves with the engine relative to the vehicle body, some relative movement between the engine and the encapsulation 16 will take place, and for this reason the flexible hoses 44 are desirable. However, these can be very short and could, in principle, be avoided altogether by integrally providing short flexible pipes extending externally from the wall 22 and connecting with the appropriate internal passageways. Instead, these short pipes could be rigid if, for example, the encapsulation is sufficiently resilient. Figures 2 and 3 also show flexible hoses 50 and 52 extending between the ends of respective ones of the internal passageways in the wall 22 to the turbo 38. As shown in Figure 3, the internal passageway in the wall 22 which is connected to the hose 50 has a portion 53 bulging from a face of the wall 22, though this is not essential.

At their other ends, the internal passageways are connected to the radiator 32 or the intercooler 34.

As shown in Figure 2, air for the turbo 38 enters through an aperture 54 and travels through an internal passageway within the wall 22 and thence to the turbo 38 via the pipe 50. After compression within the turbo 38, the air returns from the turbo through the pipe 52 which connects with a further passageway formed within the wall 22 whence it travels to the intercooler 34. After cooling there, it is fed back, through a further passageway within the block 22, and thence travels through an external pipe 55 (Figure 3) to the inlet manifold 42 of the engine.

In this way, therefore, the transport of fluids to and from the engine is greatly simplified and the need for extensive flexible hoses is greatly reduced.

In addition, where the passageways through the wall 22 terminate in opening for connection to the radiator 32 and the intercooler 34, these openings may be configured to receive the radiator and the intercooler, as the case may be, by a simple push fit: for example, the openings may be associated with suitable connection means or clip arrangements to facilitate their interconnection with the radiator and the intercooler and in a way which also supports and holds these components. At the other ends of these passage ways, where they are intended to connect to the engine or the turbo, suitable flexible extensions can be integrally carried by the wall 22 so as again to fit sealingly into position in a push-fit manner. In this way, therefore, the assembly of the engine and its ancillary components is greatly facilitated.

In a modification, the radiator 32 and/or the intercooler 34 can be formed (such as by a known process) from thermoplastic materials such as by a moulding or similar operation.

For example, such a radiator or intercooler could be integrally formed with the wall 22.

The manufacturer of a radiator in this way advantageously enables it to have a suitable non-planar shape.

Figure 4 is a diagrammatic plan view of the engine and encapsulation shown in Figures 1 to 3 though, for ease of illustration, it does not exactly correspond to those Figures. In Figure 4, the top 26 of the encapsulation is removed. In Figure 4, items corresponding to those in Figures 1 to 3 are similarly referenced.

Figure 4 shows certain items which are not visible in Figures 1 to 3: for example, a water pump 60 for the engine cooling system, the alternator 62 and the engine oil filter 64. The gearbox 36 is shown but not the drive shafts. Figure 4 shows, in dotted form, some of the passageways formed within the wall 22. For example, Figure 4 shows the passageway 66 which transports cooling water from the radiator 32 to the cooling system of the engine. As shown, the passageway 66 transports the water to an expansion chamber 68 which is also integrally formed within the wall 22. Thence, a short flexible or rigid pipe 44A connects to the cooling system. The return passageway within the wall 22, for transporting water from the engine to the radiator, is not shown.

Figure 4 also shows a passageway 70 which is formed within the wall 22 and transmits air from the entrance 54 (see Figure 2) to an air filter 72. The air filter 72 is again integrally formed within the wall 22. A short passageway 74, again formed in the wall 22, leads to the pipe 50 (see Figure 2) and thence to the turbo 38. The return passageway within the wall 22, for transporting the air from the pipe 52 and back to the intercooler 34 is not visible in Figure 4, and nor is the third passageway therein for transporting the cooled air through the block 22 to the hose 55 and thence to the engine inlet manifold 42 (see Figure 3).

Figure 5 is a diagrammatic cross-section taken on the line V-V of Figure 4 but also shows a modification. In Figure 5, the passageway 66 (see Figure 4) formed within the wall 22 is shown, leading to the expansion chamber 68. Also shown is the passageway 76 for the return flow of the water, again formed in the wall 22.

In the arrangement of Figure 5, it is assumed that a heat exchanger 78 is provided for an air-conditioning system for the vehicle. Passageways 80 and 82 formed integrally in the wall 22 transport air to and from the heat exchanger 78 for cooling purposes.

Figure 6 illustrates one way in which the support arm 30 (Figures 1 and 2) can support the engine. Figure 6 shows the support arm 30 rigidly attached to the engine 10 and extending outwardly of the engine to overlay a rigid part 80 of the vehicle body. A hydraulically damped engine mount 82 acts between the distal end of the arm 30 and the body part 80 so as to suspend the engine 10 and to damp its vibrations. Figure 6 shows part of the rear wall 18 of the encapsulation 16 and also part of the upper lid or cover 26.

These are suitably sealed to the support arm 30.

At its lower edge, the wall 18 can be secured to the extension of the encapsulation 16 below the engine. In a modification shown in Figure 6, however, the encapsulation does not continue over the whole of the underface of the engine. Instead, the oil sump 84 of the engine extends externally of the encapsulation 16, such as as shown in Figure 6 where the lower edge of the wall 18 is sealed at 86 to a flange 88 forming part of the sump 84.

In known fashion, the hydroelastic engine mount 82 includes working and compensation chambers containing hydraulic fluid which are interconnected so that the hydraulic fluid flows between the two chambers in response to engine vibration and in a manner which damps the vibrations. According to a feature of the embodiment being disclosed, the compensation chamber for the engine mount 82 may be integrally formed, such as shown at 90, in the wall 18 of the encapsulation 16, the working chamber being connected to the compensation chamber 90 by a conduit 92 formed in or carried by the support arm 30.

Because the encapsulation 16 is mounted on the engine, the engine mount 82 (and the other engine mounts not shown) will not only support the engine but will also support the encapsulation 16 and the radiator 32 and the intercooler 34 which are mounted on the encapsulation 16. Nevertheless, the encapsulation 16 can be resiliently mounted on the engine so as to be capable of a limited amount of movement relative to the engine.

According to another feature of the embodiment being described, the encapsulation 16 may be so dimensioned and mounted on the engine that, at least at a particular frequency, it tends to vibrate in anti-phase to the vibrations of the engine and helps to damp such engine vibration.

It will be understood that the encapsulation 16 is preferably made in a number of separate parts which are clipped together after having been separately positioned adjacent to the engine.

As indicated above in relation to Figure 2, air flowing through the radiator 32 and the intercooler 34 passes under the engine and under the encapsulation 16 as shown by the arrows A in that Figure. The external shape of the encapsulation can be designed to direct this flow of air towards the brake discs of the front wheels of the vehicle for cooling purposes. Because the encapsulation 16 either extends over the whole of the underside of the engine, or the whole of the underside of the engine except where the oil sump 84 protrudes, no undershield is required under the engine. The blocking effect which such an undershield has on the flow of cooling air through the engine compartment, and the resultant loss of pressure, is thus avoided. In the embodiments described, the cooling air flows directly to the road.

Different parts of the encapsulation 16 may be made of different materials, according to the functions which they are to perform and the particular operating conditions (the temperature, in particular). For the wall 22, where passageways must be formed for transporting water or air at relatively high temperatures, polyamide may be preferable.

Polypropylene, possibly reinforced with fibres, may be used elsewhere, where the temperature is not so high.

The passageways formed within the wall 22 may be formed in any suitable way, such as by blow-moulding or injection-moulding. Instead, such a passageway could be produced by forming channels in two separate sections of material and then securing them together so that the open faces of the channel are joined together and the channels then define the required passageway. Such a manufacturing method may be particularly suitable for forming larger openings such as for the expansion chamber 68 and the air filter chamber 72 (Figure 4).

Instead of mounting the intercooler 34 at the front of the engine, as shown in Figure 2, it could be mounted instead on the rear side of the engine, so as to be closer to the turbo 38.

In a modification, where it is not desired to provide complete encapsulation of the engine, the wall 22 may be provided on its own-with the passageways described-so as to provide interconnection between the radiator and/or the intercooler and the engine and/or the turbo (and for transporting other fluids such as air for the air-conditioning system).

In other words, the advantages stemming from the ease of connection provided by the wall 22 would be ensured, but without encapsulation of the engine. In such a partial implementation, the radiator 32 and the intercooler 34 could also be integrally included, particularly if they were to be made of thermoplastic material.

Such a modification is shown in Figures 7-13. In these Figures, parts corresponding to parts in Figures 1-6 are similarly referenced.

In Figure 7, the wall 22 of the previous Figures is now in the form of a block 22 which is internally formed with passageways in the same general form as for the wall 22 shown in Figures 1-6. Figure 7 shows the block 22 as having connectors 100, 102 and 104 for the engine cooling system, these connectors being shown connected to the radiator 32.

Connector 104 is at the end of a hose 106 connected to the block 22. The block 22 also supports a boss 108, preferably integrally produced with the material of the block 22, this boss 108 having connectors 110 and 112 for connection, in use, to the cooling system of the engine as will be explained. A further connector 114 is provided on the hose for receiving the water pump for the cooling system.

An air input connector 116 on the block 22 collects air for the engine. By means of an internal passageway, connector 116 is connected to a connector 118 at the end of an extension 120 of the block 22. Connector 118 is in use connected to the air input of the turbo (not shown in Figure 7). The compressed air outlet of the turbo is connected to a connector 122 and, by means of an internal passageway within the extension 120, the compressed air flows from the connector 122 to a connector 124 where it passes into an intercooler 34. The cooled air exits from the intercooler 34 into a connector 128 and flows thence through a further internal passageway to a connector 130 at the end of a short arm 132 which is part of the extension 120 of the block 22. Connector 130 is in use connected to the inlet manifold of the engine. The intercooler 34 can be separate from or integrally produced with the block 22.

Figure 8 shows the block 22 of Figure 7 connected to the engine 10 and the various ancillary components. Figure 8 shows, in dotted form, the internal passageways for the water cooling system. As shown in Figure 8, the connector 100 is connected by an internal passageway 140 to the connector 110. This internal passageway can include an enlarged volume 142 to form an expansion chamber. Figure 8 shows how the hose 106 is connected to the connector 112 by an internal passageway 144 and also to the connector 102 by an extension 146 of this passageway. Passageway 146 is normally closed, but becomes opened by the thermostat (not shown) of the cooling system so that the water which is pumped by the pump 60 returns to the radiator and bi-passes the engine cooling system. Figure 9 shows the passageways 140,144 and 146 and the expansion chamber 142. Access to this expansion chamber, for adding extra water to the cooling system, can be obtained through a cap 148 removably covering an aperture in the material 22. Figure 9 also shows the position of the hose 106.

Figure 10 corresponds to Figure 8 but shows, in dotted form, the passageways for the engine air. As shown, the air entering through the inlet 116 passes through a passageway 150 into an enlarged chamber 152 containing an air filter element 154 (see also Figure 11). The air filter element 154 may be arranged to be removable through an opening on the upper face of the block 22. The air passes from the air filter chamber 152 to the connector 118 via a passageway 156, and is compressed by the turbo 38. It then passes into the intercooler 126 via a passageway 158 and thence to the inlet manifold 160 via a passageway 162 which extends between the connectors 128 and 130.

The connection between the exhaust manifold and the turbo 38 is not shown in the Figures and will be external to the block 22 (because of its high temperature requirements).

Figure 12 corresponds to Figure 10, but shows how the block 22 can be arranged to feed air to the inlet manifold 42 of a normally aspirated engine (that is, with no turbo). The internal passageways for the cooling system are not shown in Figure 12.

Figures 7-12 therefore show how the block 22 can be used to replace a large number of interconnecting hoses, providing very simple assembly. If desired, the hose 106 can be replaced by an integral extension of the wall 22 formed with an appropriate passageway.

The arrangement shown in Figures 7-12, where the block 22 has an extension 120 carrying the intercooler for the turbo, could be further extended, in the manner generally described and explained with reference to Figures 1 to 6, so as to provide partial or complete encapsulation of the engine, and this is shown in diagrammatic form in Figure 13.

Claims (43)

1. An arrangement for transporting a fluid between an engine and a location externally of the engine, comprising a block of material in which is internally formed a passageway for the fluid.

2. An arrangement according to claim 1, in which the block is formed with a plurality of passageways each for transporting fluid to or from the engine.

3. An arrangement according to claim 1 or 2, in which the or at least one passageway connects with an enlarged hollow volume formed in the block of material.

4. An arrangement according to any preceding claim, in which the or each passageway terminates in at least one opening in a face of the block of material.

5. An arrangement according to claim 4, in which at least one opening incorporates means for connecting or is adapted to connect the passageway to an external component for receiving or supplying the fluid.

6. An arrangement according to claim 5, in which the external component is a radiator or heat exchanger.

7. An arrangement according to claim 5, in which the external component is a turbo for the engine.

8. An arrangement according to any one of claims 5 to 7, including flexible hose means for interconnecting the said opening to the said component.

9. An arrangement according to any one of claims 4 to 7, in which at least one opening incorporates means for connecting or is adapted to connect the passageway to the engine.

10. An arrangement according to claim 9, including flexible hose means for connecting the said opening to the engine.

11. An arrangement according to any preceding claim, in which the block of material is thermoplastic material.

12. An arrangement according to claim 11, in which the thermoplastic material includes polyamide material.

13. An arrangement according to claim 11 or 12, in which the thermoplastic material includes polypropylene material.

14. An arrangement according to any one of claims 11 to 13, in which the thermoplastic material is fibre-reinforced.

15. An arrangement according to claim 6, in which the block of material is thermoplastic material and the said component is made of thermoplastic material.

16. An arrangement according to any preceding claim, in which the block of material forms part of an encapsulataion which at least partly encloses the engine.

17. An arrangement according to claim 16, in which the encapsulation includes a closable opening for providing access to the engine.

18. An arrangement according to claim 16 or 17, in which the encapsulation is mounted on the engine.

19. An arrangement according to claim 18, including vibration-damping means for supporting the engine and the encapsulation mounted on it relative to a separate rigid member.

20. An arrangement according to claim 19, in which the engine is a vehicle engine and the separate rigid member is the body or chassis of the vehicle.

21. An arrangement for at least partially enclosing an internal combustion engine in a vehicle, comprising wall parts forming parts of an encapsulation and arranged to be placed around the outside of the engine and around at least some of its ancillary components but not around heat-exchanger means for the engine, one of the wall parts comprising a block of material in which is internally formed a plurality of passageways each extending between openings in respective faces of the block of material, one opening of one of the passageways being adapted for connection to heat-exchanger means on the opposite side of the block of material to the engine and the other opening of that passageway being adapted for connection to the engine or an ancillary component therefor.

22. An arrangement according to claim 21, in which the other opening of the passageway is connected to the engine or the ancillary component therefor by a hose.

23. An arrangement according to claim 21 or 22, in which the heat exchanger means is mounted with respect to the engine by the block of material.

24. An arrangement according to any one of claims 21 to 23, in which the heat exchanger means is so mounted that ambient air flows through the heat exchanger means and is directed downwardly of the engine by the encapsulation and externally over the encapsulation.

25. An arrangement according to claim 24, in which the external surface of the encapsulation is shaped to direct the flow of air from the heat exchanger means to the vicinity of the disk brake on one or more of the front wheels of the vehicle.

26. An arrangement according to any one of claims 21 to 25, in which the heat exchanger means includes a radiator for the water of the cooling system of the engine.

27. An arrangement according to claim 26, in which one of the passageways includes an enlarged volume for forming an expansion chamber for the cooling system.

28. An arrangement according to any one of claims 21 to 25, in which the heatexchanger means includes an intercooler for a turbo of the engine which is mounted externally of the encapsulation.

29. An arrangement according to any one of claims 21 to 27, in which the exhaust manifold of the engine extends through the encapsulation to the outside thereof.

30. An arrangement according to claim 28, in which the encapsulation is sealed to the exhaust manifold where the latter extends through the encapsulation.

31. An arrangement according to claim 28, in which the exhaust manifold of the engine extends through the encapsulation to the outside thereof, and including a connection from the exhaust manifold to the turbo.

32. An arrangement according to any one of claims 21 to 31, in which the inlet manifold for the engine extends through the encapsulation to the outside thereof.

33. An arrangment according to claim 32, in which the inlet manifold is sealed to the encapsulation where the manifold extends through the encapsulation.

34. An arrangement according to any one of claims 21 to 33, in which the encapsulation is mounted on the engine, and including a plurality of vibration-damping mounts for supporting the engine and the encapsulation with respect to the body of the vehicle.

35. An arrangement according to claim 34, in which the heat exchanger means is mounted on the encapsulation and the vibration-damping mounts support the engine, the encapsulation and the heat exchanger means with respect to the body of the vehicle.

36. An arrangement according to claim 34 or 35, in which each vibration-damping mount acts between the body of the vehicle and rigid support means attached to the engine and extending through the encapsulation to the outside thereof.

37. An arrangement according to any one of claims 34 to 36, in which at least one of the vibration-damping mounts is a hydro-elastic engine mount having working and compensation chambers filled with hydraulic fluid which, in response to vibrations of the engine, flows between the two chambers through means for damping the flow of fluid and the vibrations, the compensation chamber of that engine mount being separate from the engine mount and integrally formed within one of the wall parts of the encapsulation and connected to the working chamber of that engine mount by a conduit.

38. An arrangement according to any one of claims 34 to 37, in which the encapsulation is resiliently supported on the engine so as to be capable of vibrating relative thereto in a manner tending to damp vibrations of the engine.

39. An arrangement according to any one of claims 21 to 38, in which the material includes polyamide.

40. An arrangement according to any one of claims 21 to 39, in which the material includes polypropylene.

41. An arrangement according to claim 39 or 40, in which the material is reinforced with fibres.

42. An arrangement for transporting a fluid to or from an engine, substantially as described with reference to the accompanying drawings.

43. An arrangement for at least partially enclosing an internal combustion engine in a vehicle, substantially as described with reference to the accompanying drawings.