Claims:
WE CLAIM:
1. An apparatus (200) for recirculation of the exhaust gas in an engine (201), said apparatus (200) comprising a diffuser (250) fixed to an outlet pipe (245) of an exhaust gas recirculation (EGR) unit, said diffuser (250) configured to deliver at least a fraction of the re-circulated exhaust gas into the stream of fresh air flowing into the engine via an intake manifold (220),
characterized in that, the outlet of said diffuser (250) is defined by a plurality of slots (260) for directing the re-circulated gas exiting from said diffuser (250) towards said intake manifold (220).
2. The apparatus (200) as claimed in claim 1, wherein said diffuser (250) is fastened on the outer wall of said intake manifold (220), such that an operative free end of said diffuser (250) extends to the interior of said intake manifold (220).
3. The apparatus (200) as claimed in claim 2, wherein the axis of said diffuser (250) forms an angle with the longitudinal axis of said intake manifold (220) and said angle ranges from 90 to 120 degree.
4. The apparatus (200) as claimed in claim 1 comprises a flow control valve provided in said diffuser (250).
5. The apparatus (200) as claimed in claim 1, comprises a throttle body (240) with a throttle valve (241) therein configured for supplying and controlling the flow of fresh stream of air into said intake manifold (220).
6. The apparatus (200) as claimed in claim 1, wherein the distance between said diffuser (250) and said throttle valve (241) ranges from 30mm to 200mm.
7. The apparatus (200) as claimed in claim 1, wherein the distance between said diffuser (250) and runner of each cylinder (225) ranges from 10 mm to 80mm axially.
8. The apparatus (200) as claimed in claim 1 comprises a plurality of sensors that are configured for monitoring the performance of said apparatus (200).
9. The apparatus (200) as claimed in claim 1 comprises a separate control unit configured for controlling the operation of said apparatus (200).
10. The apparatus (200) as claimed in claim 1, wherein an electronic control unit (ECU) is configured for controlling the operation of said apparatus (200).
, Description:FIELD
The present disclosure relates to the field of automobile engines, and more particularly to exhaust gas recirculation in the engines.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Employing an exhaust gas recirculation (EGR) system is an effective strategy to control NOx emissions from engines. The EGR system works by recirculating a portion of an engine exhaust gas back to the engine cylinders. The system reduces NOx by lowering the oxygen concentration in the combustion chamber of engine cylinders. The EGR system is widely used in automobile engines for complying with various emission norms. The efficiency of the EGR system mainly depends on the effective mixing of the re-circulated exhaust gas. Further, sufficient mixing length is necessary to ensure uniform mixing of the re-circulated exhaust gas with fresh intake air, before the mixed air enters the combustion chamber.
However, the injection of re-circulated exhaust gas results in the deposition of soot particles on throttle valve. This reduces the life of the throttle valve, and thus the effectiveness of the EGR system. Further, high intake charge pulsation also results in the flow of soot particles towards the throttle valve. Due to the limitation of the space available in an engine compartment it is not possible to increase the distance between the location of injection of the re-circulated exhaust gas and a throttle valve beyond a certain limit.
There is, therefore, felt a need of an apparatus for exhaust gas recirculation in an engine of an automobile which alleviates the aforementioned issues.

OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
An object of the present disclosure is to provide an apparatus for exhaust gas recirculation in an engine of an automobile.
An object of the present disclosure is to provide an apparatus that ensures uniform mixing of re-circulated exhaust gas with fresh intake air.
Another object of the present disclosure is to provide an apparatus that reduces the soot deposition on a throttle valve and throttle body.
Yet another object of the present disclosure is to provide an apparatus that increases the life and durability of a throttle valve.
Another object of the present disclosure is to provide an apparatus that reduces the packaging space requirement for an engine.
Yet another object of the present disclosure is to provide an apparatus that avoids the back flow of re-circulated exhaust gas towards the throttle valve.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure envisages an apparatus for recirculation of the exhaust gas in an engine comprising a diffuser fixed to an outlet pipe of an exhaust gas recirculation (EGR) unit of the apparatus. The diffuser is configured to deliver at least a fraction of the re-circulated exhaust gas into the stream of fresh air flowing into the engine via an intake manifold. Further, the outlet of the diffuser is defined by a plurality of slots for directing the re-circulated exhaust gas exiting from the diffuser towards the intake manifold.
The diffuser is fastened to the outer wall of the intake manifold, such that the free end of the diffuser extends into the interior of the intake manifold for delivering the re-circulated exhaust gas therein.
Further, the axis of the diffuser forms an angle with the longitudinal axis of the intake manifold, and the measure of said angle ranges from 90 to 120 degrees.
A throttle body with a throttle valve provided therein is configured before the intake manifold for supplying and controlling the flow of a fresh stream of air into the intake manifold.
The distance between the diffuser and the throttle valve ranges from 30 mm to 200 mm.
According to an embodiment of the present disclosure, a flow control valve is provided in the diffuser.
The distance between the diffuser and runner of each cylinder ranges from 10 mm to 80 mm axially. Further, a control unit is provided for controlling the operation of said apparatus.
In accordance with an embodiment of the present disclosure, an electronic control unit (ECU) is configured for controlling the operation of said apparatus.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
An apparatus for exhaust gas recirculation in an engine of the present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates an isometric view of a conventional exhaust gas recirculation (EGR) unit;
Figure 2 illustrates an isometric view of an apparatus for re-circulation of exhaust gas and the intake system layout in accordance with the present disclosure;
Figure 3 illustrates a side view of an apparatus for re-circulation of exhaust gas installed on an engine;
Figure 4 illustrates a sectional view of the an apparatus for re-circulation of exhaust gas of Figure 3 along the plane C-C;
Figure 5 illustrates a side view of an intake manifold;
Figure 6 illustrates a sectional view the intake manifold of Figure 5 along the plane E-E; and
Figure 7 illustrates a sectional view the intake manifold of Figure 5 along the plane F-F.
LIST OF REFERENCE NUMERALS
100 – A conventional exhaust gas recirculation assembly
101 – Engine
104 – Intercooler inlet hose
105 – Intercooler
110 – Intercooler outlet hose
115 – Re-circulated exhaust gas cooler
120 – Intake manifold
125 – Cylinders
130 – Turbocharger outlet pipe
135 – Air cleaner
200 – Apparatus for re-circulation of exhaust gas
201 – Engine
204 – Intercooler inlet hose
205 – Intercooler
210 – Intercooler outlet hose
220 – Intake manifold
225 – Cylinder head
230 – Turbocharger outlet pipe
235 – Air cleaner housing
240 – Throttle body
241 – Throttle valve
242 – Entry of the re-circulated gas outlet pipe into the intake manifold
243 – Intake manifold flange assembly
245 – Outlet pipe of an exhaust gas recirculation unit
250 – Diffuser
260 – Slots
DETAILED DESCRIPTION
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details, are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
When an element is referred to as being "mounted on," “engaged to,” "connected to," or "coupled to" another element, it may be directly on, engaged, connected or coupled to the other element. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed elements.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Terms such as “inner,” “outer,” "beneath," "below," "lower," "above," "upper," and the like, may be used in the present disclosure to describe relationships between different elements as depicted from the figures.
A conventional assembly 100 for exhaust gas recirculation in an engine 101 is illustrated in Figure 1. The conventional assembly 100 comprises an intercooler inlet hose 104, an intercooler 105, an intercooler outlet hose 110, a re-circulated exhaust gas cooler 115, an intake manifold 120, cylinders 125, a turbocharger outlet pipe 130, and an air cleaner 135.
Compressed air from a turbocharger unit (not shown specifically in figures) of the conventional apparatus is supplied to an air cleaner 135 via the turbocharger outlet hose 130. Fresh compressed air is sent to the intercooler 105 via the intercooler inlet hose 104. After the fresh compressed air is cooled in the intercooler 105, the air is forwarded to the intake manifold 120 via the intercooler outlet hose 110. The intake manifold 120 supplies fresh compressed air to each cylinder 125 of the engine 101. An exhaust gas re-circulation (EGR) unit channels out at least a fraction of the exhaust gas to recirculate the exhaust gas into fresh air that is supplied to the cylinders 125 for combustion. The re-circulated exhaust gas is cooled by the re-circulated exhaust gas cooler 115 before being mixed with the fresh air flowing through the intercooler outlet hose 110. The conventional assembly 100 however, faces the issue of deposition of soot on a throttle body and throttle valve (not shown specifically in figures). Further, the intake charge pulsations also contribute in back flow of recirculated exhaust gas towards the throttle valve.
The present disclosure envisages an apparatus 200 for an exhaust gas recirculation in an engine 201 of an automobile, as illustrated in Figure 2 through Figure 7.
The apparatus 200 for exhaust gas recirculation in the engine 201, in accordance with the present disclosure is illustrated in Figure 2. The apparatus 200 according to the present disclosure is a part of an assembly comprising an intercooler inlet hose 204, an intercooler 205, an intercooler outlet hose 210, an intake manifold 220, cylinders 225, a turbocharger inlet pipe 230, an air cleaner housing 235, a throttle body 240, a throttle valve 241, an entry 242 of the re-circulated gas outlet pipe 245 into the intake manifold 220, an intake manifold flange assembly 243, an outlet pipe 245 of an exhaust gas recirculation unit, and a diffuser 250.
Fresh ambient air is compressed in a turbocharger (not shown specifically in figures) and supplied to the air cleaner housing 235 via the turbocharger outlet hose 230. Fresh compressed air is sent to the intercooler 205 via the intercooler inlet hose 204. The intercooler outlet hose 210 is provided at the exit of the intercooler 205. The throttle body 240 with a throttle valve (not shown in figures) provided therein, is provided between the intercooler outlet hose 210 and the intake manifold 220. The intake manifold 220 supplies the fresh air to the cylinders 225 of the engine 201. A fraction of exhaust gas channeled by an EGR unit is re-circulated and mixed with the fresh air supplied to the cylinders 225 for combustion. The re-circulated exhaust gas is cooled by the re-circulated exhaust gas cooler (not visible in figures) before mixing it with the fresh air entering the intake manifold 220. The re-circulated exhaust gas is supplied towards the intake manifold 220 via the EGR gas outlet pipe 245.
As shown in Figure 3, the throttle body 240 is fixed at the entry of the intake manifold 220. A diffuser 250 (shown in Figures 6 and 7) is fastened to the outer wall of the intake manifold 220.
Figure 4 illustrates a sectional view of the diffuser 250 and engine 201 of Figure 3 along the plane C-C. A throttle valve 241 is provided in the throttle body 240 for controlling the flow of fresh air into the intake manifold 220. The intake manifold 220 is coupled to the throttle body 240 via the intake manifold flange assembly 243. The entry 242 of the EGR gas outlet pipe 245 into the intake manifold 220 is also shown in Figure 4. The fresh air after mixing with the re-circulated exhaust gas is directed towards the cylinders 225.
The diffuser 250 for injecting the re-circulated exhaust gas into the intake manifold 220 is shown in Figures 5 through 7. The re-circulated exhaust outlet pipe 245 of an exhaust gas recirculation (EGR) unit having a flange is connected to the flange of a pipe (not shown in figures) configured to carry the re-circulated gas. The diffuser 250 is attached to the outlet of the pipe 245 via a suitable method, such as by fastening, welding, press-fitting or threading.
According to an aspect of the present disclosure, a hole is configured on the wall of the intake manifold 220 to receive the diffuser 250. Further, the diffuser 250 is welded on the surface of the outlet pipe of exhaust gas recirculation unit 245.
An angle formed between the axis of the diffuser 250 and the axis of the intake manifold 220 ranges between 90 to 120 degrees, wherein the angle is measured towards the direction of the flow of fresh air in the intake manifold 220. A plurality of slots 260 is configured on the diffuser 250, to facilitate the exit of the re-circulated gas. The slots 260 direct the flow of exhaust gas leaving the diffuser 250 towards the intake manifold 220. The slots 260, directing away from the throttle valve 241, helps in reducing the deposition of soot on the throttle valve 241 thereby increasing the life of the throttle valve 241.
According to an embodiment of the present disclosure, the distance between the diffuser 250 and the throttle valve 241 ranges from 30mm to 200mm to further reduce the soot deposition on the throttle valve 241.
According to another embodiment of the present disclosure, a flow control valve is provided in the diffuser 250 to control the proportion of the re-circulated exhaust gas that is mixed with the fresh air. Excessive mixing of exhaust gas into the fresh intake air may result in difficulty in achieving a sustained internal combustion. An electronic control unit (ECU) (not shown in figures) or any other control unit of the vehicle is can be configured for controlling the operation of the apparatus 200.
According to an aspect of the present invention, slot opening of the diffuser is faced towards the direction of fresh air intake port of the engine. This creates a better turbulence and provides an improved mixing of the exhaust gas with fresh air. The advantage of proper mixing of fresh air with the exhaust gas reduces possibility of the formation of thermal hotspots.
According to an embodiment of the present disclosure, a plurality of sensors of different types is provided at various locations in the apparatus 200 and ECU unit is configured to receive signals from these sensors. Control signals from the ECU unit in response to signals from the sensors, control the operation and performance of the apparatus 200.
According to yet another embodiment of the present disclosure, the distance between the diffuser 250 and the runner of each cylinder ranges from 10 mm to 80mm axially.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.

TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of an apparatus for exhaust gas recirculation in an engine, which:
• increases the durability of a throttle valve;
• ensures uniform mixing of re-circulated exhaust gas with fresh intake air;
• ensures an effective packaging of the exhaust gas recirculation apparatus;
• ensures that a new BS-VI engine is conveniently packaged within the existing BS-IV engine compartment; and
• avoids the back flow of re-circulated exhaust gas to throttle valve.
The foregoing disclosure has been described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.