CN110582623A

CN110582623A - Exhaust system

Info

Publication number: CN110582623A
Application number: CN201780087559.4A
Authority: CN
Inventors: 吉多·海内尔
Original assignee: Volvo Construction Equipment AB
Current assignee: Volvo Construction Equipment AB
Priority date: 2017-05-12
Filing date: 2017-05-12
Publication date: 2019-12-17
Anticipated expiration: 2037-05-12
Also published as: EP3622165A1; CN110582623B; WO2018206120A1; EP3622165B1

Abstract

The present disclosure relates to an exhaust system (1, 1') for conveying exhaust gases from an engine (2, 2') into the surroundings (3, 3 '). The exhaust system (1, 1') has an exhaust pipe (10, 10') and a tail pipe (20, 20'), wherein the tail pipe (20, 20') is arranged downstream of the exhaust pipe (10, 10 '). The tailpipe (20, 20') is tiltable in use between a first upright position (a) and a second tilted position (B) such that the tailpipe (20, 20') is adapted to deliver exhaust gas therethrough in both the first upright position (a) and the second tilted position (B). An air inlet (30, 30') is provided between the exhaust pipe (10) and the tail pipe (20, 20'), and the exhaust gas delivery device (40, 40') is positioned such that: in the second inclined position (B), the exhaust gas delivery device (40, 40') delivers exhaust gas from the exhaust pipe (10, 10') over the air inlet (30, 30') to the tail pipe (20, 20'). The disclosure also relates to an engine (2, 2') and a vehicle (4, 4') having such an exhaust system (1, 1 ').

Description

Exhaust system

Technical Field

The present disclosure relates to an exhaust system for delivering exhaust gas from an engine into the surrounding environment, the exhaust system having an exhaust pipe and a tailpipe, wherein the tailpipe is arranged downstream of the exhaust pipe, the tailpipe being tiltable in use between a first upright position and a second tilted position, such that the tailpipe is adapted to deliver exhaust gas through the tailpipe in both the first upright position and the second tilted position. The disclosure also relates to an engine and a vehicle having such an exhaust system.

Background

The invention is suitable for engineering machinery in the field of industrial construction machinery or construction equipment, in particular for road pavers. Although the invention will be described in relation to a road paver, the invention is not limited to this particular machine, but may also be used in other work machines, such as articulated haulers, excavators and backhoe loaders.

Existing pavers have a tiltable weather roof to which a likewise tiltable tail pipe is connected, for example by a retaining arm. In the normal operating position, the tailpipe is in an upright or vertical position. In the inclined position, the tailpipe is in a position that is forwardly inclined and oriented almost horizontally, in this respect, "forward" means pointing forward in the forward direction of travel of the paving machine. One reason for tilting the weather roof and tailpipe is to reduce the height of the paving machine during transport. Such transport typically occurs by placing the paver on the back of the trailer. The paving machine itself is not suitable for long distance transport at any speed associated with such transport. During periods when the weather roof and the tailpipe are tilted, the engine of the paving machine may have to be running, so that the tailpipe also needs to be operational during this position.

Due to the need for the tail pipe to function properly both in its upright position and in its inclined position, current road pavers are equipped with a tiltable tail pipe that is connected in a substantially airtight manner to an exhaust pipe that distributes the exhaust gases from the engine.

The transition between the exhaust pipe and the tailpipe is designed in the form of a large hinge that also delivers the exhaust gas in order to do so without imposing any undue gas transport restrictions in this area.

Disclosure of Invention

It is an object of the present disclosure to provide an exhaust system having an improved design while maintaining functionality with respect to tiltability and gas distribution.

This object is achieved by a system according to claim 1. The object is therefore achieved by an exhaust system for delivering exhaust gases from an engine into the surroundings, wherein the exhaust system has an exhaust pipe and a tail pipe, wherein the tail pipe is arranged downstream of the exhaust pipe, the tail pipe being tiltable in use between a first upright position and a second tilted position such that the tail pipe is adapted to deliver exhaust gases therethrough in both the first upright position and the second tilted position, wherein an air inlet is provided between the exhaust pipe and the tail pipe, and wherein the exhaust delivery device is positioned such that: in the second inclined position, the exhaust gas delivery device delivers exhaust gas from the exhaust pipe to the tailpipe across the air inlet.

This is a simple yet convenient and practical design that enables air to enter the tailpipe to cool the exhaust passing through the tailpipe while maintaining the gas delivery functionality. In the first upright position the tail pipe delivers exhaust gas in the usual manner, and in the second inclined position the exhaust gas delivery device is positioned such that it delivers exhaust gas from the exhaust pipe to the tail pipe over the air inlet. By this simple design, a less complex and less cumbersome design is achieved.

Thus, the design is less expensive than known designs. This design enables substantially complete separation of the tailpipe from the tailpipe when desired. This design can also eliminate the need for any seals between the exhaust pipe and the tailpipe. The disclosed system can also separate the hinge or tilt function from the exhaust delivery function. The hinge may be separate from the exhaust delivery path through the exhaust pipe and tailpipe. The oblique point may also be separate from the exhaust pipe and the tail pipe. It also minimizes any restriction effect on exhaust gas delivery at the transition between the exhaust pipe and the tailpipe.

According to an embodiment, the exhaust gas delivery device is a part of the tailpipe at the inlet end of the tailpipe, and the exhaust gas delivery device protrudes towards the exhaust pipe such that: in the second inclined position, the exhaust gas delivery device is located vertically above the outlet end of the exhaust pipe. This is a simple and effective way of achieving the objects of the present disclosure. In the second inclined position, the exhaust gas delivery device acts as a collection umbrella or trap for the exhaust gases as they exit the outlet end of the exhaust pipe and collects them for entry into the inlet end of the tailpipe.

According to an embodiment, in the second inclined position, the exhaust gas delivery device substantially covers the outlet of the outlet end of the exhaust pipe. Typically, the hot exhaust gas rises substantially vertically as it exits the exhaust pipe. In this way, substantially all of the exhaust gas is captured by the exhaust gas delivery device and carried into the tailpipe.

According to an embodiment, in the first upright position, the profile of the inlet end of the tailpipe substantially follows the profile of the outlet end of the exhaust pipe with a non-zero distance from the outlet end of the exhaust pipe. Typically, the hot exhaust gas rises substantially vertically as it exits the exhaust pipe. In this way, substantially all of the exhaust gas is captured by and carried into the inlet end of the tailpipe, while leaving a gap for the air inlet.

According to an embodiment, the air inlet extends along at least a major part of the circumference of the exhaust pipe and/or tailpipe. Thereby, sufficient air is allowed to enter the tailpipe to allow cooling of the exhaust gas.

According to an embodiment, the air inlet is arranged at a side of the exhaust system towards which the tail pipe can be tilted. The location of the air inlet allows for simplification of the tilting function, at least in part due to the open design and the associated reduced amount of material in the tilted or folded region of the exhaust pipe-tailpipe interface. Airtight transport is no longer required, which simplifies the design.

According to an embodiment, the hinge connects the exhaust pipe and the tail pipe in a tiltable manner. The hinge may be located away from the exhaust-tailpipe interface, may also be described as a transport region at the air inlet between the exhaust pipe and the tailpipe (where the exhaust gas delivery device transports exhaust gas from the exhaust pipe across the air inlet to the tailpipe), and may therefore be located at a location that is more suitable from a vehicle design standpoint and less disruptive to the transport of exhaust gas between the exhaust pipe and the tailpipe.

According to one embodiment, the hinge is located near the inlet end of the tailpipe and near the outlet end of the exhaust pipe. This hinge need not be located exactly at the inlet end of the tailpipe or at the outlet end of the exhaust pipe, but may be slightly offset from the inlet end of the tailpipe or the outlet end of the exhaust pipe, for example to achieve an inclined path of the tailpipe with respect to the exhaust pipe, which is advantageous.

According to one embodiment the exhaust pipe is provided with a venturi system near its outlet end or said tailpipe near its inlet end for letting in ambient air for cooling the exhaust gas flowing through the exhaust pipe or tailpipe. The venturi system enables additional air to be introduced (e.g., into the tailpipe) for cooling of the exhaust gas. The venturi system defines an improved mixing between the air and the exhaust gas.

According to an embodiment the tail pipe is provided near its inlet end with a further air inlet system for letting in ambient air for cooling the exhaust gas flowing through the tail pipe, wherein the further air inlet system preferably has a plurality of air inlet openings positioned transversely to the exhaust gas flow direction of the tail pipe. The additional air inlet system enables additional air to be introduced (e.g., into the tailpipe) for cooling of the exhaust gas. The further air inlet system is preferably located at the inlet end of the tailpipe.

According to an embodiment, the exhaust pipe protrudes into the tail pipe in both the first upright position and the second inclined position. This is a simple and effective way of achieving the objects of the present disclosure. The exhaust pipe preferably has a smaller cross-sectional size than the tail pipe. In this way, the exhaust pipe may protrude into the tailpipe, both providing space for the air inlet around it and maintaining the exhaust gas delivery path from the exhaust pipe to the tailpipe in both the first upright position and the second inclined position.

According to an embodiment, the exhaust pipe protrudes beyond the further air inlet system into the tailpipe. Thus, proper mixing of air and exhaust gas can be achieved.

According to one embodiment, the cross-sectional area of the tailpipe is larger than the cross-sectional area of the exhaust pipe. This design allows all or substantially all of the exhaust to be delivered into the tailpipe.

According to an embodiment, the tailpipe is adapted to convey exhaust gas through the tailpipe at any position between the first upright position and the second inclined position. It may sometimes be advantageous to be able to use the exhaust system also in any intermediate position.

according to an embodiment, the angle between the first upright position and the second inclined position is at least 30 degrees, preferably at least 45 degrees, and more preferably at least 60 degrees.

According to an embodiment, the first upright position of the tailpipe is a substantially vertical position, and the second inclined position is a substantially horizontal position. The substantially vertical position of the tailpipe is a common position for exhaust systems of this type, and the substantially horizontal position allows for maximum height reduction, for example in transport conditions.

According to one embodiment, the outlet end of the exhaust pipe is held in its position in both the first upright position and the second inclined position of the tail pipe. Thus, the outlet end of the exhaust pipe is easily adapted to the design of the vehicle without negatively affecting the design.

According to an embodiment, the tailpipe is the end section of the exhaust system, such that the exhaust gas exits the exhaust system and enters the ambient environment when exiting the tailpipe.

According to an embodiment, the air inlet covers about 50% of the circumference of the tailpipe, and thus the exhaust gas delivery device covers about 50% of the circumference of the tailpipe. The exhaust gas delivery means may cover between 25% and 75%, preferably between 35% and 65%, and more preferably between 40% and 60% of the circumference of the tailpipe, in order to trap and deliver the exhaust gas in an efficient manner.

according to an embodiment, the engine is an internal combustion engine. The internal combustion engine thus produces exhaust gas which needs to be transported away, and the exhaust system functions well for transporting the exhaust gas away.

According to an embodiment, a vehicle is disclosed that includes an exhaust system of the type described above.

According to one embodiment, the vehicle is a construction equipment vehicle, such as a paver.

According to an embodiment, the tailpipe is adapted to be tiltable together with a foldable part of the vehicle, e.g. a foldable weather roof.

According to an embodiment, the tailpipe is connected to the foldable portion of the vehicle by a hinge at or near its outlet end, such that the tailpipe and the foldable portion are tilted together between a first upright position and a second tilted position.

Further advantages and advantageous features of the invention are disclosed in the following description and in the dependent claims.

Drawings

With reference to the accompanying drawings, the following is a more detailed description of embodiments of the disclosure cited as examples.

In these figures:

Fig. 1a is a side view of a paving machine equipped with an exhaust system of the type of the present disclosure, the exhaust system being in a first upright position,

Fig. 1b is the same view as in fig. 1a, wherein the exhaust system is in a second tilted position,

FIG. 2 is an enlarged side view of the exhaust pipe-tail pipe interface of FIG. 1a,

Figure 3 is a perspective view of the embodiment of figure 2,

Figure 4 is an enlarged side view of the exhaust pipe-tailpipe interface of figure 1b,

Figure 5 is a perspective view of an alternative exhaust system,

Figure 6 is a perspective view of an exhaust system according to the prior art,

FIG. 7 is a side view of an exhaust pipe-tailpipe interface in a first upright position, according to an alternative embodiment, and

fig. 8 is a side view of the embodiment of fig. 7 in a second tilted position.

Detailed Description

starting from the disclosure of fig. 1a, a paver 4 of a generally known type is shown, which paver 4 is equipped with an exhaust system 1 of the type disclosed herein. The exhaust system 1 is in an upright vertical position a, which is the main operating position a of the exhaust system 1 and of the paver 4. This position is hereinafter referred to as the first upright position a. In this position a, exhaust from engine 2 of paving machine 4 is carried through exhaust pipe 10 and tailpipe 20 before exiting the tailpipe into ambient environment 3. Paving machine 4 may be equipped with additional equipment, such as an exhaust aftertreatment system, for cleaning the exhaust gases at least to some extent before they enter ambient environment 3. Any such additional equipment is typically connected to the exhaust pipe 10 downstream of the engine 2 and upstream of the tailpipe 20, and it is not part of this disclosure and therefore is not shown in any of the drawings.

The paving machine 4 is equipped with a weather roof 5, which weather roof 5 is also shown in its upright, generally vertical working position a. The weather roof 5 generally comprises four generally vertical posts 6 (one at each corner), these posts 6 holding the roof 5 itself in place, and this roof 5 serves to protect the driver of the paver 4 from the wind and the sun. The weather roof panel 5 is of a generally known type and is also not the subject of the present disclosure.

The tail pipe 20 is connected to the weather roof panel 5 by a retaining arm 7. The retaining arm 7 is rotatably connected at one end to the weather roof panel 5 and at the opposite end to the tail pipe 20. The retaining arm 7 is of a generally known type and is not the subject of the present disclosure. When the weather roof panel 5 is locked in its upright position (which corresponds to the first upright position a of the tail pipe 20), the holding arm 7 maintains the first upright position a of the tail pipe 20. As shown in fig. 1B, when the weather roof panel 5 is tilted to the lowered second tilted position B, the tail pipe 20 follows the movement of the weather roof panel 5 into its own second tilted position B. The reason for tilting the weather roof 5 and the tail pipe 20 is to lower the height of the paver, for example, during its transport on the trailer of a truck. It should be noted that paving machine 4 is adapted to operate with weatherproof roof 5 and tailpipe 20 in second inclined position B as well, such that engine 2 generates exhaust gases that need to be carried away from engine 2 and any personnel handling paving machine 4. For the sake of clarity, it should also be noted that the exhaust gases produced in the engine 2 are conveyed as follows: from the engine 2 through the exhaust pipe 10 into the tailpipe 20 and out of the tailpipe 20 to the surrounding environment 3.

the engine 2 is an internal combustion engine, preferably of the gasoline or diesel type, but it is also conceivable to use any type of engine 2 for producing exhaust gases for any type of fuel.

The exhaust system 1 of the present disclosure may be used with other types of vehicles 4, such as for any type of construction equipment or other vehicle type.

In fig. 2, the exhaust system 1 is shown in more detail. This figure is an enlarged cross-sectional view of the area around the exhaust pipe-tailpipe interface in fig. 1 a. Shown is a hood 8 of paving machine 4, which hood 8 covers and protects engine 2 (as shown in fig. 1a and 1b), and may also be designed to give paving machine 4 an elegant design. The engine cover 8 is provided with holes 9, which holes 9 are used for protruding the exhaust system 1 from the engine 2 into the surroundings 3. As can be seen, the exhaust pipe 10 is connected to an exhaust manifold that is part of the engine 2 and is given a suitable curvature to have its outlet end 11 in a substantially vertical position, the outlet end 11 extending through the aperture 9 (the aperture 9 extending through the engine bonnet 8). The outlet end 11 has an outlet 12, which outlet 12 is an opening through which exhaust gas can pass. The outlet end 11 of the exhaust pipe 10 terminates substantially in a plane corresponding to the plane at the aperture 9 of the engine bonnet 8. The engine cover 8 is inclined in the forward direction of the paver 4. In the depicted embodiment, the outlet end 11 of the exhaust pipe 10 is also inclined at an angle substantially corresponding to the angle of inclination of the engine hood 8. This can be designed in other ways, for example with a horizontal engine hood 8, wherein the outlet end 11 of the exhaust pipe 10 is also positioned horizontally. The edge of the outlet end 11 of the exhaust pipe 10 may also be designed not to follow the exact angle of inclination of the bonnet 8 and the aperture 9 or other designs of the bonnet 8 and the aperture 9. The hole 9 through the bonnet 8 is larger than the outer circumference of the exhaust system 1.

The inlet end 21 of the tail pipe 20 is located substantially vertically above the outlet end 11 of the exhaust pipe 10. Thus, during use of paving machine 4, i.e., during operation of engine 2, hot exhaust gas rises through outlet end 11 of exhaust pipe 10 into inlet end 21 of tailpipe 20. The exhaust pipe 10 has a rounded (substantially circular) cross section, while the tail pipe 20 has a polygonal cross section having a substantially rectangular main shape. The tail pipe 20 has a cross-sectional area larger than that of the exhaust pipe 10. As seen in the horizontal plane, tailpipe 20 is also larger than exhaust pipe 10 so that the inlet end 21 of tailpipe 20 is able to capture and deliver almost all of the exhaust gas from engine 2 even though there may be a side wind blowing around paving machine 4. The tailpipe 20 and the exhaust pipe 10 each have an axial center axis, and the position and direction of the center axis of the tailpipe 20 at said exhaust pipe-tailpipe interface substantially correspond to the position and direction of the center axis of the exhaust pipe 10. The curvature of the exhaust pipe 10 between the engine 2 and the outlet end 11 of the exhaust pipe 10 may be of any design to bridge the gap between the engine 2 and the exhaust-pipe interface. Tailpipe 20 may be positioned in paving machine 4 such that tailpipe 20 is proximate to engine 2 while not blocking the view of the driver of paving machine 4. Therefore, the overall curvature of the exhaust pipe 10 is adapted to the current positions of the inlet ends 21 of the engine 2 and the tail pipe 20, respectively.

The tail pipe 20 is a separate part from the exhaust pipe 10. This means that: although the exhaust pipe 10 and the tail pipe 20 are positioned close to each other, they are not made as one piece. There is a non-zero distance in the form of an air inlet 30 between the outlet end 11 of the exhaust pipe 10 and the inlet end 21 of the tailpipe 20. About half of the circumference of the inlet end 21 of the tail pipe 20 is positioned vertically about 1cm or more above the engine hood 8 to let ambient air into the tail pipe 20 and cool the hot exhaust gases during use. The distance may be smaller or larger. It may also have a curved opening, as in the second embodiment disclosed later. The distance between the outlet end 11 of the exhaust pipe 10 and the inlet end 21 of the tail pipe 20 may also be provided below the engine hood 8. This particular design depends on how much ambient air is desired for the exhaust cooling function and where most of the ambient air should be drawn. The distance is between at least 0.5cm and 5cm, and preferably between at least 1cm and 5 cm. An air inlet 30 is located in the tailpipe 20 in the forward direction of the paving machine 4 to collect ambient air. The design of the tailpipe 20 on its opposite side (the side not shown in the figures) is substantially similar to that shown, so that the tailpipe 20 is symmetrical along its axial extension.

The tail pipe 20 is tiltably connected to the paver 4 by bolts 50. The bolt 50 represents a hinge 50, and any type of hinge joint may be used as an alternative to the bolt 50. Bolts 50 connect the tailpipe 20 to a beam 60 of the paving machine 4, which beam 60 is rigidly mounted under the engine bonnet 8, for example, to maintain the tailpipe 20 in position. The tailpipe 20 is thus adapted to tilt or rotate about the bolt 50 between its first upright position a and its second tilted position B. Depending on the position of the bolt 50 relative to the tailpipe 20, different paths may be implemented. In the present embodiment, the tail pipe 20 is provided with a U-shaped lever 41 at a distance from the inlet end 21 of the tail pipe 20, and the bolt 50 is in a direction transverse to the forward direction of the paver 4, so that the tail pipe 20 is substantially inclined forwards. As seen in the cross-sectional view of the tail pipe 20, the U-shaped lever 41 is shaped in a U-shape. Another advantage obtained by the distance between said oblique point (i.e. the position of the bolt 50 with respect to the inlet end 21 of the tailpipe 20) and the inlet end 21 of the tailpipe 20 is: the portion of the inlet end 21 of the tail pipe 20 is configured not to interfere with the outlet end 11 of the engine cover 8 or the exhaust pipe 10. The position of the tilting point can also be set more freely than in known exhaust systems in which the tilting point is part of the exhaust path. Therefore, the inclined point is also separated from the exhaust pipe 10 and the tail pipe 20. In this embodiment, the point of inclination is forward of the air inlet 30 at the exhaust pipe-tailpipe interface.

It should be noted that the outlet end 11 of the exhaust duct 10 is typically fixed in position relative to the paving machine 4. This means that the relative movement between the outlet end 11 of the exhaust pipe 10 and the inlet end 21 of the tailpipe 20 is provided only by the tilting movement of the inlet end 21 of the tailpipe 20.

As can be seen in fig. 2, the inlet end 21 of the tailpipe 20 is provided with an exhaust gas delivery device 40. In the present embodiment, the exhaust gas delivery device 40 is designed as a tongue (tongue) that projects in a vertically downward direction from the inlet end 21 of the tail pipe 20 and away from the rest of the tail pipe 20. Thus, the exhaust gas delivery device 40 extends in the axial direction of the tail pipe 20.

When the tailpipe 20 is in its first upright position a, a U-shaped lever 41 is fastened to the lowest point of the exhaust gas delivery means 40. The lever 41 may be made in one piece with the exhaust delivery device 40 and the tailpipe 20, or may be a separate piece that is then fastened to the exhaust delivery device 40 and the tailpipe 20. Also, the exhaust delivery device 40 may preferably be made in one piece with the rest of the tailpipe 20, but may alternatively be made as a separate part fastened to the tailpipe 20. Exhaust gas delivery device 40 completely surrounds outlet end 11 of exhaust pipe 10 at the rear end of exhaust pipe 10, but does not completely surround along exhaust pipe 10 (as viewed in the forward direction of paving machine 4). The width of the exhaust gas delivery device 40 is approximately the balance between a sufficiently large air inlet 30 and a sufficiently large exhaust gas delivery device 40, as seen in the circumferential direction of the tailpipe 20. In this embodiment, the air inlet 30 covers slightly less than 50% of the circumference of the tailpipe, and thus the exhaust gas delivery device 40 covers slightly more than 50% of the circumference of the tailpipe. It is contemplated that the exhaust gas delivery device 40 should preferably cover 25% to 75%, preferably 35% to 65%, and most preferably 40% to 60%, in order to capture and deliver the exhaust gas in an efficient manner.

In fig. 3, the embodiment of fig. 2 is shown in perspective view, including a full length tailpipe 20. The exhaust system 1 is shown in its first upright position a. The tailpipe 20 is at its vertical top portion designed in a known manner and this is not discussed further here.

In the first upright position a of the tail pipe 20 the exhaust gas delivery device 40 is not used, or at least not substantially used, for any delivery action of the exhaust gas, since the position of the inlet end 21 of the tail pipe 20 relative to the outlet end 11 of the exhaust pipe 10 serves this purpose, but as can be seen from fig. 4 the exhaust gas delivery device 40 is in the second inclined position B for collecting the exhaust gas from the exhaust pipe 10 and delivering it into the tail pipe 20. As the hot exhaust gas rises upward, the hot exhaust gas encounters the exhaust delivery device 40 and is delivered into the tailpipe 20. In this second inclined position B, the exhaust gas conveying device 40 is therefore located above the outlet end 11 of the exhaust pipe 10 in the vertical direction. In the second inclined position B, the exhaust gas transport device 40 covers the outlet 12 of the outlet end 11 of the exhaust pipe 10 more to capture and transport the entire exhaust gas from the exhaust pipe 10. As can be seen from fig. 4, the exhaust gas delivery device 40 has a small overlap with the outlet end 11. This overlap is as seen in the side view of fig. 4. The reason for the overlap is to deliver the entire exhaust gas, but another design may be contemplated if it is acceptable to deliver a slightly reduced proportion of the exhaust gas or if a design other than the overlap is found to be advantageous. Such another design may include the exhaust delivery device 40 protruding in the axial direction of the tail pipe 20 with the same curvature as the tail pipe 20.

When the tailpipe 20 is in this second inclined position B, the tailpipe 20 may abut the engine hood 8 of the paving machine 4 at the forward front of the air inlet 30. However, the shape of the air inlet 30 is such that: there is still an open area on the side of the air inlet 30 with respect to the wall of the tailpipe 20 so that ambient air can enter. However, the shape of the air inlet 30 may be designed in other ways. In the present embodiment, the design is mainly for: when in the first upright position a conforms to the design of the hood 8 and bridges the distance to the exhaust delivery device 40 and the lever 41 to hold the tailpipe 20 in place.

In fig. 5, an alternative embodiment of the present disclosure is disclosed, wherein an exhaust pipe-tailpipe interface of the type disclosed above is used, but an additional air inlet system 31 has been added at the lower part of the tailpipe 20. The further air inlet system 31 takes the form of a plurality of air inlet openings 31a, 31b positioned transversely to the exhaust gas flow direction of the tail pipe 20. This additional air inlet system 31 may be used with other embodiments of the exhaust pipe-tailpipe interfaces disclosed herein (e.g., the embodiments disclosed below with reference to fig. 7-8). The tailpipe 20 or exhaust pipe 10 may also be provided with a venturi system (not shown), for example internally, near the inlet end 21 or at the outlet end 11, respectively, in order to improve the mixing of the exhaust gases with the surrounding air. The venturi system may take the form of a reduced diameter over a short axial extension of the tailpipe 20 or exhaust pipe 10. The major diameter is then reset downstream of the venturi system.

Fig. 6 shows an exhaust gas transport system 1PA according to the prior art for comparison with the present disclosure. The exhaust path is indicated by the arrows through the system. The exhaust gas flows upward from the engine in an exhaust conduit 10PA that protrudes through a gap in the engine cover 8 PA. A large hinge joint 50PA is located vertically above the hood 8PA, which hinge joint 50PA serves the dual purpose of conveying exhaust gases and providing a tilting function for the system 1 PA. In addition, it is also airtight. The exhaust gases are then conveyed out into the surroundings 3 and released at a level which is higher in the vertical direction. This is a complicated and expensive construction which, for example, places high demands on manufacturing tolerances.

The hinge joint 50PA takes the form of a cylinder divided about its middle part into two substantially symmetrical halves 52PA, 53PA, said halves 52PA, 53PA being joined together for relative rotational movement. The joint 51PA is sealed to avoid any gas leakage. The hinge joint 50PA increases the restriction to the gas flow path.

Attention is now directed to fig. 7 and an alternative embodiment of the present disclosure. With respect to the above disclosed embodiments, similar details are given similar reference numerals. The present embodiment includes an exhaust system 1' having an exhaust pipe 10' and a tail pipe 20 '. In this embodiment, the exhaust pipe 10 'protrudes through an aperture 9' in the bonnet 8 'of the paver 4'. In this embodiment, the exhaust pipe 10 'protrudes slightly further into the tail pipe 20'. Thus, there is a slight overlap between the outlet end 11 'of the exhaust pipe 10' and the inlet end 21 'of the tailpipe 20'. The protruding length of the outlet end 11 'of the exhaust pipe 10' into the inlet end 21 'of the tail pipe 20' may be selected to be longer than depicted in fig. 7. The air inlet 30' is provided in a forward direction of the inlet end 21' of the tail pipe 20 '. The outlet end 11 'of the exhaust pipe 10' is open in its vertical top portion for conveying the exhaust gas. The lowermost portion of the tail pipe 20 'as seen in the vertical direction is provided with an exhaust gas delivery device 40', which exhaust gas delivery device 40 'serves to capture exhaust gas from the exhaust pipe 10' and deliver the exhaust gas over the air inlet 30 'into the tail pipe 20' in the second inclined position B.

In the embodiment of fig. 7, the hinge with the bolt 50 'for holding the tailpipe 20' and tilting the tailpipe 20 'is located behind the outlet end 11' of the exhaust pipe 10', as seen in the forward direction of the paver 4'. This location may be used with any of the embodiments of the exhaust system herein. In the present embodiment, this position is chosen because the inclination of the tailpipe 20' is not hindered by the position of the exhaust pipe 10', and the air inlet 30' is dimensioned to receive the outlet end 11' of the exhaust pipe 10' in the second inclined position B, which is shown in fig. 8.

In this embodiment, the upper portion of the tailpipe 20' may conform to any of the embodiments previously described herein. The lower part of the exhaust gas delivery device 40' is not only closed in the lateral surface of the tail pipe 20', but also in a part extending rearwards, starting from the hinge 50' and as seen in the forward direction of the paver 4' (i.e. the part facing the engine hood 8' and the paver 4' in the first upright position a of the exhaust system 1' and being positioned in the second inclined position B such that exhaust gas is captured from the exhaust pipe 10' and delivered into the tail pipe 20 '). This closed surface portion together with the lateral surface of the tail pipe 20 'in this region (i.e. the dimensions and configuration of the exhaust gas delivery device 40') should at least be such that it is adapted to deliver exhaust gas from the exhaust pipe 10 'over the air inlet 30' to the tail pipe 20 'in the second inclined position B in use of the exhaust system 1'. It can be said that the exhaust gas delivery device 1' substantially covers the outlet 12 of the outlet end 11' of the exhaust pipe 10' in the second inclined position B. For this reason, it may not be necessary to have a surface that is closed all the way to the hinge 50', since the outlet end 11' of the exhaust tube 10' is much higher in this embodiment.

In all the embodiments disclosed above, the first upright position a of the tailpipe 10, 10' is vertical or almost vertical, i.e. substantially at an angle of 0 to 15 degrees with respect to the vertical. However, the tail pipes 10, 10' may be slightly angled with respect to the vertical direction as desired. The second inclined position B of the tailpipes 10, 10' may be nearly horizontal, as desired, but in the depicted embodiment there is an angle of about 45 degrees between the first upright position a and the second inclined position B. It is contemplated that the angle may be between at least 30 degrees and at least 60 degrees, within which the height of paving machine 4, 4' is low enough to, for example, meet any transport height requirements.

It is to be understood that the invention is not limited to the embodiments described above and shown in the drawings; rather, one of ordinary skill in the art appreciates that various modifications and changes can be made within the scope of the claims set forth below. These modifications may involve the use of an exhaust system without the attached weather roof disclosed above. The tailpipe may for example be equipped with its own locking mechanism to maintain the first upright position and for release to lower the tailpipe to the second inclined position.

The size and shape of the exhaust pipe and tailpipe may be designed differently than disclosed above. The exhaust pipe may be given any shape, for example polygonal, and the tailpipe may also be designed differently, for example with rounded design. They may also differ in their mutual cross-sectional dimensions, for example by having equal cross-sectional areas. The tailpipe may also be designed to accommodate more than one exhaust pipe, or to accommodate one exhaust pipe and a plurality of additional pipes, such as pipes that deliver bitumen-containing gas from the rear of the paving machine during its use. Such additional gas (e.g., a bitumen-containing gas) may also be mixed with ambient air to cool and dilute the additional gas. These pipes may preferably be arranged alongside one another, as seen in the forward direction of the paver, but other designs may also be used. It is contemplated to have all of the gas inlet pipes enter the inlet end of a tailpipe having a rectangular design to keep the overall cross-sectional dimension low. Therefore, the size of the inlet end of the tailpipe needs to be adapted to the number of tubes to capture and deliver gas from these tubes. Another option is to add any additional gas upstream of the outlet end of the exhaust pipe so that only one pipe meets the tailpipe at the exhaust pipe-tailpipe interface. It is further contemplated to adapt the exhaust system to deliver machine compartment air into the tailpipe. Proper ventilation of the engine compartment can thus be achieved.

Another embodiment may be some other location of the point of inclination of the exhaust pipe-tailpipe interface. It may be positioned completely behind the exhaust-tailpipe interface, as viewed in the forward direction of the paving machine, but may also be located side-by-side at the exhaust-tailpipe interface, as desired. It is contemplated that the relative movement between the outlet end of the exhaust pipe and the inlet end of the tailpipe may be achieved by a combined movement of the outlet end of the exhaust pipe and the inlet end of the tailpipe relative to each other. However, it is a prerequisite that the exhaust gas delivery means in the second inclined position is adapted to deliver exhaust gas from the exhaust pipe to the tail pipe over the air inlet.

Although not specifically required, all of the above embodiments of the exhaust system may be used to deliver exhaust gas from the exhaust pipe to the tailpipe over the air inlet at any position between the first upright position and the second inclined position. The design, location and specific type of hinges, levers and bolts may be altered. The bolt can for example be exchanged for any kind of general fastening member that enables a rotational movement of the tailpipe.

Claims

1. An exhaust system (1, 1') for conveying exhaust gases from an engine (2, 2') into the surroundings (3), the exhaust system (1, 1') having an exhaust pipe (10, 10') and a tail pipe (20, 20'), wherein the tail pipe (20, 20') is arranged downstream of the exhaust pipe (10, 10'), the tail pipe (20, 20') being tiltable in use between a first upright position (A) and a second tilted position (B) such that the tail pipe (20, 20') is adapted to convey exhaust gases through the tail pipe in both the first upright position (A) and the second tilted position (B), characterized in that an air inlet (30, 30') is provided between the exhaust pipe (10, 10') and the tail pipe (20, 20'), and, the exhaust gas delivery device (40, 40') is positioned such that: in the second inclined position (B), the exhaust gas delivery device (40, 40') delivers exhaust gas from the exhaust pipe (10, 10') over the air inlet (30, 30') to the tail pipe (20, 20').

2. The exhaust system (1, 1') according to claim 1, wherein the exhaust gas delivery device (40, 40') is a portion of the tailpipe (20, 20') at its inlet end (21, 21'), and the exhaust gas delivery device (40, 40') protrudes towards the exhaust pipe (20, 20') such that: in the second inclined position (B), the exhaust gas conveying device is located above the outlet end (11, 11') of the exhaust pipe (10, 10') in the vertical direction.

3. Exhaust system (1, 1') according to claim 2, wherein in the second inclined position (B) the exhaust gas delivery means (40, 40') substantially covers an outlet (12) of the outlet end (11, 11') of the exhaust pipe (10, 10').

4. Exhaust system (1, 1') according to any one of claims 2 to 3, wherein in the first upright position (A) the profile of the inlet end (21, 21') of the tailpipe (20, 20') substantially follows the profile of the outlet end (11, 11') of the exhaust pipe (10, 10') with a non-zero distance from the outlet end (11, 11') of the exhaust pipe (10, 10 ').

5. The exhaust system (1, 1') according to any one of the preceding claims, wherein the air inlet (30, 30') extends along at least a major part of the circumference of the exhaust pipe (10, 10') and/or the tailpipe (20, 20').

6. The exhaust system (1, 1') according to any one of the preceding claims, wherein the air inlet (30, 30') is provided on a side of the exhaust system (1, 1') towards which the tailpipe (20, 20') is tiltable.

7. The exhaust system (1, 1') according to any one of the preceding claims, wherein a hinge (50, 50') tiltably connects the exhaust pipe (10, 10') and the tail pipe (20, 20').

8. The exhaust system (1, 1') according to claim 7, wherein the hinge (50, 50') is located near an inlet end (21, 21') of the tailpipe (20, 20') and near an outlet end (11, 11') of the exhaust pipe (10, 10').

9. the exhaust system (1, 1') according to any one of the preceding claims, wherein the exhaust pipe (10, 10') is provided with a venturi system near an outlet end (11, 11') of the exhaust pipe (10, 10') or the tail pipe (20, 20') near an inlet end (21, 21') of the tail pipe (20, 20') for letting in ambient air for cooling the exhaust gas flowing through the exhaust pipe or the tail pipe.

10. The exhaust system (1, 1') according to any one of the preceding claims, wherein the tail pipe (20, 20') is provided with a further air inlet system (31) near the inlet end (21, 21') of the tail pipe (20, 20'), the further air inlet system (31) being for letting in ambient air for cooling the exhaust gas flowing through the tail pipe.

11. The exhaust system (1, 1') according to claim 10, wherein the further air inlet system (31) has a plurality of air inlet openings (31a, 31b) positioned transverse to the exhaust gas flow direction of the tail pipes (20, 20').

12. The exhaust system (1') according to any one of the preceding claims, wherein in both the first upright position (a) and the second inclined position (B) the exhaust pipe (10') protrudes into the tail pipe (20 ').

13. The exhaust system (1, 1') according to any one of the preceding claims, wherein the cross-sectional area of the tail pipe (20, 20') is larger than the cross-sectional area of the exhaust pipe (10, 10 ').

14. The exhaust system (1, 1') according to any one of the preceding claims, wherein the tail pipe (20, 20') is adapted to convey exhaust gas through the tail pipe in any position between the first upright position (a) and the second inclined position (B).

15. an exhaust system (1, 1') according to any of the preceding claims, wherein the angle between the first upright position (A) and the second inclined position (B) is at least 30 degrees, preferably at least 45 degrees, and more preferably at least 60 degrees.

16. the exhaust system (1, 1') according to claim 15, wherein the first upright position (a) of the tail pipe (20, 20') is a substantially vertical position and the second inclined position (B) is a substantially horizontal position.

17. the exhaust system (1, 1') according to any one of the preceding claims, wherein the outlet end (11, 11') of the exhaust pipe (10, 10') is held in place at the outlet end (11, 11') in the first upright position (a) and the second inclined position (B) of the tail pipe (20, 20 ').

18. The exhaust system (1, 1') according to any one of the preceding claims, wherein the tail pipe (20, 20') is a terminal section of the exhaust system (1, 1') such that the exhaust gas exits the exhaust system (1, 1') and enters the surroundings (3) when exiting the tail pipe (20, 20 ').

19. An engine (2, 2'), the engine (2, 2') comprising an exhaust system (1, 1') according to any of the preceding claims, the engine (2, 2') preferably being an internal combustion engine.

20. A vehicle (4, 4'), the vehicle (4, 4') comprising an exhaust system (1, 1') according to any one of claims 1 to 17.

21. Vehicle (4, 4') according to claim 20, wherein the vehicle (4, 4') is a construction equipment vehicle, such as a road paver.

22. Vehicle (4, 4') according to any of claims 20 to 21, wherein the tail pipe (20, 20') is adapted to be tiltable together with a foldable part (5) of the vehicle (4, 4'), the foldable part (5) being for example a foldable weather roof.

23. Vehicle (4, 4') according to claim 22, wherein the tailpipe (20, 20') is connected to the foldable portion (5) of the vehicle (4, 4') by a hinge at or near the outlet end of the tailpipe, such that the tailpipe (20, 20') and the foldable portion (5) are tilted together between the first upright position (a) and the second tilted position (B).