TECHNICAL FIELD
[0001] The present disclosure relates, in general, to emission control systems for an internal combustion engine, and particularly to an exhaust gas recirculation 5 (EGR) system for the internal combustion engine.
BACKGROUND
[0002] Background description includes information that may be useful in understanding the present subject matter. It is not an admission that any of the 10 information provided herein is prior art or relevant to the presently claimed subject matter, or that any publication specifically or implicitly referenced is prior art.
[0003] Hitherto, in motor vehicles powered by an internal combustion engine, an exhaust gas recirculation (EGR) system has been commonly installed for 15 reducing NOx emissions produced by the engine. As is known, the EGR system is designed to recirculate a metered amount of exhaust gas into the air-fuel mixture in the combustion chambers to reduce the temperature in the combustion chambers and thus NOx emissions. Whereas in gasoline engines, EGR is generally added to increase the fuel economy by decreasing the part load pumping 20 losses.
[0004] In the EGR systems, an exhaust gas tapping taken from exhaust system is connected to an inlet of an EGR cooler to cool the exhaust gases received from an exhaust gas outlet. The EGR cooler then supplies the exhaust gases to an EGR valve installed at an outlet of an EGR passage formed inside a cylinder head of an 25 internal combustion engine. The EGR passage extends forward to an inlet connection formed at an intake manifold of the internal combustion engine.
[0005] Such configuration of the EGR systems is generally suitable for vertically mounted engines because of ease of assembly and good transient
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response with shorter EGR circuit paths. However, EGR systems having parts mounted on the cylinder head is found not suitable for inclined mounting of the engines, for example, in vehicles where the engine is to be mounted beneath the driver seat. During under seat mounting, fouling of the EGR pipes and the EGR valve with the underbody of the vehicle is observed, which is not desired. Also, 5 the entire length of the EGR circuit path increases, which will have effect on the transient response.
[0006] Various approaches in the state of the art has been adopted. But none of them is able to address the aforementioned issues related to the EGR system. Accordingly, it is a need in the state of the art to find another mounting location 10 for the EGR components on the engine.
OBJECTS OF THE DISCLOSURE
[0007] Some of the objects of the present disclosure, which at least one embodiment herein satisfy, are listed hereinbelow. 15
[0008] A general object of the present disclosure is to provide an exhaust gas recirculation (EGR) system for an inclined engine transmission layout.
[0009] An object of the present disclosure is to provide an exhaust gas recirculation (EGR) system for an inclined engine transmission layout in which the entire length of the EGR circuit path is reduced in comparison to the existing 20 EGR systems.
[0010] Yet another object of the present disclosure is to find a suitable mounting position for an exhaust gas recirculation (EGR) system on an inclined engine transmission layout.
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SUMMARY
[0011] This summary is provided to introduce concepts related to an exhaust gas recirculation (EGR) system for an internal combustion engine. The concepts
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are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
[0012] The present disclosure relates to an exhaust gas recirculation (EGR) 5 system for an internal combustion engine. The EGR system includes an exhaust gas tapping taken from an exhaust system mounted on cylinder block; an EGR connecting passage formed inside transmission casing to connect to and extend rearward from an exhaust gas outlet; an EGR cooler connected between an inlet of the EGR connecting passage and the exhaust gas outlet; an EGR valve mounted at 10 the transmission casing so as to receive exhaust gas from an outlet of the EGR connecting passage; and an EGR output pipe connecting an output of the EGR valve to an EGR inlet connection formed at an intake system of the internal combustion engine.
[0013] In an aspect, the exhaust system includes an exhaust manifold and a 15 Catalytic converter mounted on the cylinder block.
[0014] In an aspect, the EGR system is for inclined transmission layout of the internal combustion engine.
[0015] In an aspect, the EGR system includes an EGR valve adapter integrated with the transmission casing to mount the EGR valve over the 20 transmission casing.
[0016] In an aspect, the EGR connecting passage is formed in case transmission front.
[0017] In an aspect, the EGR cooler is connected between the inlet of the EGR connecting passage and a catalytic converter positioned downstream to an 25 exhaust manifold. In the said aspect, the EGR valve is positioned in such a way that the EGR valve is near to the intake system and away from the catalytic converter.
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[0018] These and other objects and advantages of the present invention will be apparent to those skilled in the art after a consideration of the following detailed description taken in conjunction with the accompanying drawings in which a preferred form of the present invention is illustrated.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The illustrated embodiments of the subject matter will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems, 10 and methods that are consistent with the subject matter as claimed herein, wherein:
[0020] FIG. 1 illustrates a perspective view of an existing exhaust gas recirculation (EGR);
[0021] FIG. 2 illustrates a perspective view of an exhaust gas recirculation 15 (EGR) in accordance with an embodiment of the present disclosure; and
[0022] FIG. 3 illustrates a cross-sectional view of an EGR connecting passage formed inside transmission casing in accordance with an embodiment of the present disclosure.
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DETAILED DESCRIPTION
[0023] The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to 25 clearly communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives
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falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0024] It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, 5 and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
[0025] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a”, “an” and “the” are intended to include the 10 plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, 15 components and/or groups thereof.
[0026] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts 20 involved.
[0027] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should 25 be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
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[0028] Embodiments and/or implementations described herein relate to an exhaust gas recirculation (EGR) system. In FIG. 1, a structure of the existing EGR system 100 is shown. In the EGR system 100, an exhaust gas tapping taken from an exhaust system is tapped at a connection point 102 to connect to an inlet of an EGR cooler 104 to cool the exhaust gases received from the exhaust gas outlet. 5 The EGR cooler 104 then supplies the exhaust gases to an EGR valve 106 installed at an outlet of an EGR passage 108 formed inside a cylinder head of an internal combustion engine. The EGR passage 108 extends forward, through an EGR outlet pipe 110, to an inlet connection 112 formed at an intake manifold of the internal combustion engine. 10
[0029] Such configuration of the EGR system 100 is generally suitable for vertically mounted engines because of ease of assembly However, as mentioned above, the EGR system 100 having parts mounted on the cylinder head is found not suitable for inclined mounting of the engines, for example, in vehicles where the engine is to be mounted beneath the driver seat. During under seat mounting, 15 fouling of the EGR pipes and the EGR valve with the underbody of the vehicle is observed, which is not desired. Also, the entire length of the EGR circuit path increases, which will have effect on the transient response.
[0030] To this, the present disclosure proposes a new improved EGR system 200, as shown in FIG. 2, in accordance with an embodiment of the present 20 disclosure. As can be seen from FIG. 2, the EGR system 200 includes an exhaust gas tapping taken from exhaust system. The exhaust manifold mounted on cylinder body is connected to a catalytic converter 202. At an outlet end of the catalytic converter 202, an EGR tapping 204 is performed to supply the exhaust gases to an EGR connecting passage 206 formed inside a transmission casing 208 25 to connect to and extend rearward from the catalytic converter 202 or the exhaust gas outlet. FIG. 3 illustrates a cross-sectional view of the EGR connecting passage 206 formed inside transmission casing 208. As can be seen, the EGR connecting passage 206 is formed in case transmission front or clutch side of the transmission casing 208. 30
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[0031] In an aspect, an EGR cooler 210 is connected between an inlet of the EGR connecting passage 206 and the exhaust gas outlet or the catalytic converter 202. In an example, the EGR cooler 210 is a water-cooled type, in which the exhaust gases introduced into the inside thereof is cooled by the cooling water introduced therein. 5
[0032] Further, an EGR valve 212 is mounted at the transmission casing 208 in such a way that it receives exhaust gases from an outlet of the EGR connecting passage 206. In an aspect, as can be appreciated by those skilled in the art, the EGR valve 212 is opened or closed by a signal transmitted by engine control unit (ECU). Through the EGR valve 212, a metered amount of the exhaust gases 10 produced by the engine is supplied through an EGR output pipe 214 to an EGR supply connection 216 formed at an intake system of the internal combustion engine.
[0033] In an aspect, the EGR system 200 is for inclined transmission layout of the internal combustion engine. 15
[0034] In an aspect, the EGR system 200 includes an EGR valve adapter integrated with the transmission casing 208 to mount the EGR valve 212 over the transmission casing 208.
[0035] Thus, with the proposed EGR system 200, and by providing EGR connecting passage 206 inside the transmission casing 208, fouling is completely 20 avoided. Also, since the length of EGR circuit is comparatively less than the convention EGR layout, transient response is also improved.
[0036] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. It will be appreciated that several of the above-disclosed and other features and 25 functions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may subsequently be made by
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those skilled in the art without departing from the scope of the present disclosure as encompassed by the following claims.
[0037] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, 5 including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.
[0038] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the 10 claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.
TECHNICAL ADVANTAGES 15
[0039] The present invention disclosure provides a provide an exhaust gas recirculation (EGR) system that is suitable for an inclined engine transmission layout.
[0040] The present disclosure provides an exhaust gas recirculation (EGR) system in which an EGR connecting passage is formed inside a transmission 20 casing. With the formation of the EGR connecting passage is formed inside a transmission casing, fouling is completely avoided, and the stiffness and strength of the transmission casing is enhanced.
[0041] The present disclosure provides an exhaust gas recirculation (EGR) system the circuit length of which is comparatively less than the convention EGR 25 layout, resulting into an improved transient response.
[0042] The present disclosure provides an exhaust gas recirculation (EGR) system in which no additional pipes and clamps are used.

We claim:
1. An exhaust gas recirculation (EGR) system (200) for an internal combustion engine, the EGR system (200) comprising:
an exhaust tapping taken from an exhaust system mounted on a cylinder block; 5
an EGR connecting passage (206) formed inside a transmission casing (208) to connect to and extend rearward from the exhaust gas outlet;
an EGR cooler (210) connected between an inlet of the EGR connecting passage (206) and the exhaust gas outlet; 10
an EGR valve (212) mounted at the transmission casing (208) so as to receive exhaust gas from an outlet of the EGR connecting passage (206); and
an EGR output pipe (214) connecting an output of the EGR valve (212) to an EGR supply connection (216) formed at an intake system of 15 the internal combustion engine.
2. The EGR system (200) as claimed in claim 1 is for inclined transmission layout of the internal combustion engine.
3. The EGR system (200) as claimed in claim 1, comprising an EGR valve adapter integrated with the transmission casing (208) to mount the EGR 20 valve (212) over the transmission casing (208).
4. The EGR system (200) as claimed in claim 1, wherein the EGR connecting passage (206) is formed in case transmission front.
5. The EGR system (200) as claimed in claim 1, wherein the EGR cooler (210) is connected between the inlet of the EGR connecting passage (206) 25 and a catalytic converter (202) positioned downstream to an exhaust manifold.
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6. The EGR system (200) as claimed in claim 5, wherein EGR valve (212) is positioned in such a way that the EGR valve (212) is near to the intake system and away from the catalytic converter (202).