Claims:We claim:

1. An integrated multi-chamber air intake manifold for tractor engines, the air intake manifold comprising:

• a recirculated exhaust gas (EGR)-air mixing chamber having an inlet for fresh air and an inlet port for EGR to be mixed with fresh air for combustion;

• an intake manifold volume disposed under the EGR-air mixing chamber for storing mixture of air and EGR therein; and a first passage connecting it to the EGR-air mixing chamber;

• an additional air reservoir to act as a buffer for reducing ramming effects during combustion; the reservoir being connected to the intake manifold volume and EGR-air mixing chamber via a second passage adjacent the first passage;

wherein the integrated air intake manifold is configured as a semi-plenum type manifold having low-height and increased volume with reduced runner length for reducing the pressure drop across thereof, to help in controlling the ramming effect during combustion.

2. Integrated multi-chamber air intake manifold as claimed in claim 1, wherein the recirculated exhaust gases (EGR) laterally enters the EGR-air mixing chamber through a mixing tube connected to the EGR inlet port.

3. Integrated multi-chamber air intake manifold as claimed in claim 2, wherein the mixing tube has a plurality of perforations for uniform distribution of the recirculated exhaust gases (EGR) entering into the EGR-air mixing chamber.

4. Integrated multi-chamber air intake manifold as claimed in claim 1, wherein a plurality of ports is configured in the intake manifold volume for discharging the mixture of air-EGR based on the suction in the engine combustion chamber for subsequent combustion therein.
5. Integrated multi-chamber air intake manifold as claimed in claim 1, wherein the first passage is configured in the floor at the end of the EGR-air mixing chamber away from the fresh air inlet.

6. Integrated multi-chamber air intake manifold as claimed in claim 5, wherein a profiled wall is configured at the end of the EGR-air mixing chamber away from the fresh air inlet, the profiled wall includes two side walls and a roof converging into a substantially hemispherical shape open at the bottom through the first passage for ensuring uniform mixing of air with EGR to create a smooth flow of air-EGR mixture through the first passage.

7. Integrated multi-chamber air intake manifold as claimed in claim 6, wherein the second passage is configured between the intake manifold volume and the additional air reservoir and formed under the end of the EGR-air mixing chamber away from the fresh air inlet.

8. Integrated multi-chamber air intake manifold as claimed in claim 4, wherein the plurality of ports for discharging the air-EGR mixture are laterally disposed close to the bottom of the intake manifold volume.

9. An integrated multi-chamber air intake manifold for tractor engines, the air intake manifold comprising:

• an open recirculated exhaust gas (EGR)-air mixing chamber;

• an intake manifold volume disposed in parallel and under the EGR-air mixing chamber configured with a first passage for connecting it to the EGR-air mixing chamber; and

• an additional air reservoir connected to the intake manifold volume and EGR-air mixing chamber via a second passage disposed adjacent the first passage;

wherein the integrated air intake manifold is configured as a semi-plenum type manifold with the recirculated exhaust gases (EGR) entering the EGR-air mixing chamber through an EGR inlet port connected to a mixing tube having a plurality of perforations.
10. Integrated multi-chamber air intake manifold as claimed in claim 9, wherein the mixing tube connected to the EGR inlet port is disposed transverse to the length of the EGR-air mixing chamber.

Dated: this 21st day of September, 2016. SANJAY KESHARWANI
APPLICANT’S PATENT AGENT , Description:FIELD OF INVENTION

The present invention relates to a compact intake manifold for a tractor engine. In particular, the present invention relates to a multi-chamber manifold for improving the performance of the setting for mixing the recirculated exhaust gases with the intake air. More particularly, the present invention relates to an integrated multi-chamber intake manifold for a tractor engine.

BACKGROUND OF THE INVENTION

Some of the tractor models are poor from the accessibility point of view in that due to less packaging space available on the engine top at tractor level the tappet setting operation becomes tedious. The hot side servicing is generally restricted by keeping the operator’s safety in mind. This, tappet setting has to be done necessarily from the intake or cold side.

Removing the tappet cover and performing correct tappet setting are two critical engine servicing operations at any service station. Moreover, because of the engine height and complexity of these operations, at least two operators are required to perform this tappet removal and setting operations. The set-up for mixing the exhaust gas recirculation (EGR) and intake air and configuration of the elbow connector are the critical parameter for deciding the engine height and thereby the visibility of the operator.

Therefore, in order to eliminate these disadvantages and to minimize the labor work and reducing the service time, the engine height needs to be reduced for increasing the visibility. Further, eliminating EGR mixing setup and connecting elbow could also be useful. However, from the emission point of view, these two are essential parts and cannot be eliminated from the engine. So, the required the space needs to be made for tappet setting at tractor level, but without affecting any emission-related parameters.

Nowadays, it is necessary to provide a compact product with enhanced performance as well as better aesthetic appeal and ergonomics of the engine with lesser cost.
PRIOR ART

The applicant’s own Patent Application No. 2948/MUM/2010 discloses (Fig. 1) an intake manifold with EGR mixing device for automobile engines comprises an intake manifold of engine block connected a first pipe to a turbocharger run by the exhaust gas of the engine to receive fresh air through a venturi with throat section passage; an exhaust manifold of the said engine connected to said intake manifold venturi throat section passage by a second pipe to re-circulate partially exhaust gas into the said fresh air through an involute passage with direction flow at 90° to the said flow of fresh air; and the out let of the said involute passage made tangential to the said venturi throat section passage throat section.

DISADVANTAGES WITH THE PRIOR ART

The following are the disadvantages with the conventional air intake manifold for tractor engines discussed above:

• Longer air-intake manifold.

• Less space above the manifold, so servicing is tedious and time-consuming.

• Pressure drop across the manifold.

• Requires at least two persons for engine servicing at service stations.

• Assembly time is more due to more number of components.

OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:

An object of the present invention is to provide a compact intake manifold for a tractor engine.

Another object of the present invention is to provide a multi-chamber intake manifold with reduced height, but increased volume.
Still another object of the present invention is to provide a multi-chamber intake manifold for configuring an effective air-flow path.

Yet another object of the present invention is to provide a multi-chamber intake manifold for actively improving the EGR and intake air mixing operation.

A still further object of the present invention is to provide a multi-chamber intake manifold, which is compatible both for naturally aspirated and turbo-charged engine.

A yet further object of the present invention is to provide a multi-chamber intake manifold to increase the visibility of the operator during tappet setting operation.

A yet further object of the present invention is to provide a multi-chamber intake manifold, which reduces pressure drop across the manifold.

These and other objects and advantages of the present invention will become more apparent from the following description, when read with the accompanying figures of drawing, which are however not intended to limit the scope of the present invention in any way.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided an integrated multi-chamber intake manifold comprising:

• a recirculated exhaust gas (EGR)-air mixing chamber having an inlet for fresh air and an inlet port for EGR to be mixed with fresh air for combustion;

• an intake manifold volume disposed under the EGR-air mixing chamber for storing mixture of air and EGR therein; and a first passage connecting it to the EGR-air mixing chamber;

• an additional air reservoir to act as a buffer for reducing ramming effects during combustion; the reservoir being connected to the intake manifold volume and EGR-air mixing chamber via a second passage adjacent the first passage;

wherein the integrated air intake manifold is configured as a semi-plenum type manifold having low-height and increased volume with reduced runner length for reducing the pressure drop across thereof, to help in controlling the ramming effect during combustion.

Typically, the recirculated exhaust gases (EGR) laterally enters the EGR-air mixing chamber through a mixing tube connected to the EGR inlet port.

Typically, the mixing tube has a plurality of perforations for uniform distribution of the recirculated exhaust gases (EGR) entering into the EGR-air mixing chamber.

Typically, a plurality of ports is configured in the intake manifold volume for discharging the mixture of air-EGR based on the suction in the engine combustion chamber for subsequent combustion therein.

Typically, the first passage is configured in the floor at the end of the EGR-air mixing chamber away from the fresh air inlet.

Typically, a profiled wall is configured at the end of the EGR-air mixing chamber away from the fresh air inlet, the profiled wall includes two side walls and a roof converging into a substantially hemispherical shape open at the bottom through the first passage for ensuring uniform mixing of air with EGR to create a smooth flow of air-EGR mixture through the first passage.

Typically, the second passage is configured between the intake manifold volume and the additional air reservoir and formed under the end of the EGR-air mixing chamber away from the fresh air inlet.

Typically, the plurality of ports for discharging the air-EGR mixture are laterally disposed close to the bottom of the intake manifold volume.

In accordance with the present invention, there is also provided an integrated multi-chamber air intake manifold for tractor engines, the air intake manifold comprising:
• an open recirculated exhaust gas (EGR)-air mixing chamber;
• an intake manifold volume disposed in parallel and under the EGR-air mixing chamber configured with a first passage for connecting it to the EGR-air mixing chamber;
• an additional air reservoir connected to the intake manifold volume and EGR-air mixing chamber via a second passage disposed adjacent the first passage;

wherein the integrated air intake manifold is configured as a semi-plenum type manifold with the recirculated exhaust gases (EGR) entering the EGR-air mixing chamber through an EGR inlet port connected to a mixing tube having a plurality of perforations.

Typically, the mixing tube connected to the EGR inlet port is disposed transverse to the length of the EGR-air mixing chamber.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will be briefly described with reference to the accompanying drawings, wherein:

Figure 1 shows a schematic arrangement in a conventional turbocharged diesel engine of the applicant.

Figure 2 shows a front view of the conventional EGR-fresh air mixing set-up of the engine of Fig. 1.

Figure 3 shows a perspective close-up view of two operators necessary for doing tappet setting operation.

Figure 4a shows an engine with a conventional EGR-fresh air mixing set-up of Fig. 1.

Figure 4b shows an engine having an integrated multi-chamber intake manifold configured in accordance with the present invention.

Figure 5a shows a cross-sectional view of the integrated multi-chamber air intake manifold configured in accordance with the present invention.

Figure 5b shows another cross-sectional view of the integrated multi-chamber air intake manifold of Figure 5a depicting the profiled wall for uniform flow.

Figure 5c shows a cross-sectional view of the integrated multi-chamber air intake manifold with an open EGR chamber having three openings or gates.

Figure 5d shows a typical flow of air and EGR while being mixed in the integrated multi-chamber air intake manifold 114 of Fig. 5a

Figure 6a shows a perspective external view of the integrated multi-chamber air intake manifold configured in accordance with the present invention and depicted assembled with progressive EGR valve setup.

Figure 6b shows another perspective external view of the integrated multi-chamber air intake manifold configured in accordance with the present invention depicted without progressive EGR valve setup.

Figure 7 shows a perspective view of the engine equipped with the integrated multi-chamber air intake manifold configured in accordance with the present invention.

Figure 8 shows a mixing tube 130 assembled on the multi-chamber intake manifold 114 through EGR entry port 120

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

In the following, an integrated multi-chamber intake manifold for a tractor engine and configured in accordance with the present invention will be described in more details with reference to the accompanying drawings without limiting the scope and ambit of the present invention in any way.

Figure 1 shows a typical turbocharged diesel engine 10 comprising a block 1, an intake manifold 2 and an exhaust manifold 3. A turbocharger 4 is mounted on the exhaust manifold 3. An intake pipe 5 runs from the turbocharger 4 to the intake manifold 2. The exhaust gases are routed back to engine through EGR (exhaust gas recirculation) pipe 6. The exhaust gases mix with fresh air at point 7. After combustion, the exhaust gases exit from the exhaust manifold 3 and enter the turbocharger 4 and subsequently exit therefrom passing through the exhaust system 8. Fresh air enters from air filter 9 into turbocharger 4. The pressurized air from turbocharger 4 to the intake manifold 2 passes through the intake pipe 5. However, the point 7 for mixing the EGR with fresh air is disposed inside intake manifold 2.

Figure 2 shows a perspective view of the conventional EGR-fresh air mixing set-up of the engine 10 of Fig. 1. It includes a set-up 12 for mixing the exhaust gas recirculation (EGR) and fresh intake air from air intake manifold 14 connected to each other via an elbow 16.

Figure 3 shows a perspective close-up view of the EGR and fresh air mixing set-up 12 of Figure 2 and the tappet cover side. Here, at least two operators (Op1 on cold side 18 and Op2 on the tappet cover side 19) are necessary for doing tappet setting operation.

Figure 4a shows an engine 10 having a conventional EGR-fresh air mixing set-up of Fig. 1. Here, the height of the flange 15 of the elbow 16 is the topmost component of the engine 10.

Figure 4b shows an engine 100 having an integrated multi-chamber intake manifold 114 configured in accordance with the present invention. Here, the engine 100 has substantially lower heights H1 and H2 of the multi-chamber intake manifold 114 in comparison with the conventional engine 10 shown in Figure 3 having the conventional EGR-fresh air mixing set-up.

Figure 5a shows a cross-sectional view of the integrated multi-chamber air intake manifold 114 configured in accordance with the present invention. It includes three chambers, i.e. EGR mixing chamber 122 and intake manifold volume 124 connected to each other via a passage 126 and an additional air reservoir 128 is connected to the integrated chambers 122, 124 via another passage 129. Since a plenum chamber operates opposite to the principle of a vacuum chamber, a positively pressurized plenum chamber naturally forces air out and causes the air present outside the chamber to replace it. Accordingly, the integrated EGR mixing chamber 122 and the semi-plenum type intake manifold 114 is used here. Four ports 121, 123, 125 and 127 are clearly visible in figure. This integrated configuration of the intake manifold 114 and EGR mixing chamber 122 has substantially reduced height but increased volume because of the reduced runner length (semi-plenum type) of the intake manifold 114. This result in additional volume in the air reservoir 128, which reduces pressure drop and helps in controlling the ramming effect during combustion. Moreover, semi-plenum configuration of the intake manifold 114 also enables a further reduction in pressure drop across it to improve the air-flow therethrough. EGR enters through port 120 and is mixed with fresh air entering from inlet 110 of the EGR mixing chamber 122. A particular improvement is the mixing tube 130 having a plurality of perforations (Fig. 8) for properly spreading the EGR in the EGR mixing chamber 122. The perforations in the mixing tube 130 in Figure 8 decide the amount of EGR to be mixed into the EGR mixing chamber 122.

Figure 5b shows another cross-sectional view of the integrated multi-chamber air intake manifold of Figure 5a depicting the profiled wall 131 for uniform flow. This profile is having one circular draft 132b within two convergent walls with drafts 131a, which ensure the mixing of air and create a smooth flow towards the entry point 126. The merging of 122 and 124 is termed as mixed air entry point 126, which has a semi-circular shape with uniform drafts 131a which helps in sending the mixed air to the intake manifold volume 124.

Figure 5c shows a cross-sectional view of the integrated multi-chamber air intake manifold with an open EGR chamber having three openings or gates G1, G2 and G3. Fresh air is received through the first gate (G1) 110 and EGR is injected through the second gate (G2) 120. After mixing fresh air with EGR, the mixture is delivered through the third gate (G3) 126, which is stored in the additional air reservoir 128 for combustion depending on the suction of the combustion chamber to reach the combustion area through the ports 121,123,125 and 127 (Fig. 5a).

Figure 5d shows a typical flow of air and EGR while being mixed in the integrated multi-chamber air intake manifold 114 of Fig. 5a. It includes a mixing tube 130 having a plurality of perforations for properly spreading the EGR in the EGR mixing chamber 122. After mixing fresh air with EGR, the mixture is delivered through the third gate (G3) or passage 126.

Figure 6a shows a perspective external view of the integrated multi-chamber air intake manifold 114 configured in accordance with the present invention and laterally assembled with progressive EGR valve setup 112. As discussed in respect of Figures 4a, 4b, here the height of the integrated air intake manifold 114 is substantially smaller than the conventional air intake manifold 14 of Figure 1 fitted with the EGR-fresh air mixing set-up 12 above it.

Figure 6b shows another perspective external view of the integrated multi-chamber air intake manifold configured in accordance with the present invention depicted without progressive EGR valve setup 112.

Figure 7 shows a perspective view of the engine 100 equipped with the integrated multi-chamber air intake manifold 114 configured in accordance with the present invention. Here, due to less cluttered head cover, its visibility to the operator is substantially improved in comparison to the engine 10 equipped with the conventional separate air intake manifold 14 and EGR-air mixing set-up 12. The characteristic feature of the integrated multi-chamber air intake manifold configured in accordance with the present invention is that the point of mixing the fresh air with the EGR is disposed inside the integrated intake manifold 114 itself and not outside as in the conventional turbocharged diesel engine with a separate EGR chamber and air-intake manifold (Applicant’s earlier Indian Patent Application No. 2948/MUM/2010) described in respect of Figures 1 and 2.

Figure 8 shows a mixing tube 130 assembled on the multi-chamber intake manifold 114 through EGR entry port 120. Mixing tube 130 is having a plurality of perforations 115 for properly spreading the EGR in the EGR mixing chamber 122. The perforations 115 in the mixing tube 130 decide the amount of EGR to be mixed into the EGR mixing chamber 122 (Fig. 5a).

WORKING OF THE INVENTION

Fresh air cleaned by the air-filter enters through the EGR-air mixing chamber to be mixed there with the exhaust gases recirculated for reducing excess oxygen content and combustion chamber temperature and thereby for reducing the NOx to improve emission from the engine.

TECHNICAL ADVANTAGES AND ECONOMIC SIGNIFICANCE

An integrated multi-chamber air intake manifold configured in accordance with the present invention has the following advantages:

• Reduced height and increased volume of the air intake manifold.

• Actively improved EGR mixing with the fresh intake air.

• Compatible both for naturally aspirated and turbocharged engines by using a mixing tube.

• Reduced intake manifold runner length by semi plenum configuration of the manifold.

• More space on top of the manifold due to reduced height of the manifold.

• Semi-plenum type intake manifold enables in reducing the pressure drop across the manifold.

• Improved airflow due to reduced pressure drop.

• Mixing tube with perforations spreads exhausts gas within EGR-air mixing chamber.

• With reduced height of the integrated intake manifold, an additional air reservoir is feasible for reducing the pressure drop across the manifold and for controlling the ramming effect during combustion.

• Compact integrated air intake manifold ensures 100% mixing of fresh air with EGS for reducing the emission parameters due to an increased air flow rate.

• Reduced number of components reduce the engine assembly time resulting in eliminating a sub-assembly station. Just one new part (integrated manifold) added at the cost of almost 10 parts (which include elimination of 2 leakage joints).

• Improved productivity (by reduction in time, no. of operations, lower failure rate and reduction in operator’s efforts).

• Ease to assemble high pressure pipes and to operate.

• Simple to construct and assemble.

• Ease of making components casted both in aluminum and ferrous materials.

• Reduced weight, i.e. total weight reduced by up to 6 kg in case of aluminum casted manifold.

• Improved aesthetics of the engine by optimized space management and engine packaging, i.e. by reducing the engine height almost by 110 mm and by parallel routing of the high pressure pipes fixed with rigid supports.

• Offers higher durability, strength, reliability.

• Improved safety by reducing the hot EGR pipe length and by shifting hot pipes positions downwards to the manifold to provide sufficient and safe access to the engine top compartment to help in service personnel engaged in tappet setting and injector end air leak-off sealing.

The foregoing description of the specific embodiments will 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.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. The description provided herein is purely by way of example and illustration. The various features and advantageous details are explained with reference to this non-limiting embodiment in the above description in accordance with the present invention.
The descriptions of well-known components and manufacturing and processing techniques are consciously omitted in this specification, so as not to unnecessarily obscure the specification. It is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

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, the skilled person will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments described herein and easily make innumerable changes, variations, modifications, alterations and/or integrations in terms of materials and method used to configure, manufacture and assemble various constituents, components, subassemblies, assemblies and in terms of the size, shapes, orientations and interrelationships without departing from the scope and spirit of the present invention.

The numerical values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the disclosure unless there is a statement in the specification to the contrary.

Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, shall be understood to implies including a described element, integer or method step, or group of elements, integers or method steps, however, does not imply excluding any other element, integer or step, or group of elements, integers or method steps.

The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention.