Engine EGR (Exhaust Gas Recirculation) pipeline

Abstract

The invention belongs to the technical field of engines, and discloses an engine EGR pipeline. Wherein the first pipeline and the second pipeline are parallel to each other, the first pipeline is wavy, a first channel and a second channel in the first pipeline are alternately connected, the second pipeline is wavy, a third channel and a fourth channel in the second pipeline are alternately connected, and a first auxiliary pipe is communicated with a wave trough where the first channel and the second channel are connected; the first auxiliary pipe extends in the direction of the first channel and communicates with the fourth channel, and the other end of the first auxiliary pipe is bent towards the second pipeline. A wave crest where the third channel and the fourth channel are connected is communicated with a second auxiliary pipe, the second auxiliary pipe extends in the direction of the fourth channel and is communicated with the first channel, and the other end of the second auxiliary pipe is bent towards the first pipeline; the problem that in the prior art, a valve block of a one-way valve is broken under impact, and cylinder score occurs to an engine is solved.

Description

Technical Field

[0001] The invention relates to the technical field of engines, and in particular to an EGR pipeline of an engine. Background Art

[0002] At present, medium and heavy-duty natural gas engines choose the equivalent combustion route to reach the National VI emission limit. Compared with lean combustion, equivalent combustion significantly increases the heat load and knock risk in the engine cylinder, and the fuel consumption of effective work is higher than that of lean combustion. However, the current high-pressure cooling EGR pipeline can reduce the heat load and knock tendency, thereby reducing the fuel consumption of the engine. The impact of EGR on the combustion in the engine cylinder is also much greater than that of lean combustion. In the EGR pipeline, even when the EGR valve is opened to the maximum, the introduction of EGR often has certain difficulties in the turbocharger engine. When the boost pressure is low at low load, the exhaust gas can be introduced before the turbine and connected to the turbocharger, relying on the advantage that the exhaust gas pressure before the turbine is higher than the fresh air pressure after supercharging. At high load, the pressure of the air after supercharging is higher. Even if the EGR valve is opened to the maximum, the exhaust gas cannot be introduced into the intake pipe because the boost pressure will be higher than the exhaust pressure. In the prior art, in order to prevent the pressurized fresh air from flowing back into the exhaust gas, an EGR check valve is usually installed on the EGR pipeline, and the exhaust pulse can be well utilized to increase the EGR flow rate, thereby ensuring sufficient exhaust gas supply and improving the EGR rate, such as patents CN200985843Y a check valve, CN202100349U an EGR check valve and CN112392631A EGR check valve and EGR system.

[0003] At present, the valve plate of the EGR check valve is a cantilever beam structure. Since the EGR gas passing through the EGR check valve is pulsed, the valve plate of the EGR check valve bends back and forth under the action of the pulsed airflow, and the valve plate performs high-frequency movement under the influence of the exhaust pulse. The valve plate is more likely to break at the bend, and the debris of the broken part of the valve plate will enter the engine intake system through the intake duct, affecting the normal operation of the engine and even causing the engine to pull the cylinder. The service life of the EGR check valve is short, and it will also cause permanent damage to the engine. Summary of the invention

[0004] The purpose of the present invention is to provide an engine EGR pipeline to solve the problem in the prior art that the valve plate of the one-way valve is broken under impact, resulting in cylinder scuffing in the engine.

[0005] To achieve this purpose, the present invention adopts the following technical solutions: The present invention provides an engine EGR pipeline, including a first pipeline and a second pipeline, the first pipeline and the second pipeline are parallel to each other, the first pipeline is wavy, the first pipeline includes a first channel and a second channel, the first channel and the second channel are alternately connected, and the first channel and the second channel are connected in a V shape, the second pipeline is wavy, the second pipeline includes a third channel and a fourth channel, the third channel and the fourth channel are alternately connected, and the third channel and the fourth channel are connected in a V shape; a first auxiliary pipe is connected at the trough where the first channel and the second channel meet, the first auxiliary pipe extends in the direction of the first channel and is connected to the fourth channel, and the other end of the first auxiliary pipe is bent toward the second pipeline; a second auxiliary pipe is connected at the peak where the third channel and the fourth channel meet, the second auxiliary pipe extends in the direction of the fourth channel and is connected to the first channel, and the other end of the second auxiliary pipe is bent toward the first pipeline.

[0006] Preferably, the junction between the first channel and the second channel is arc-shaped.

[0007] Preferably, the angle between the first channel and the second channel is an obtuse angle.

[0008] Preferably, the junction between the third channel and the fourth channel is arc-shaped.

[0009] Preferably, the angle between the third channel and the fourth channel is an obtuse angle.

[0010] Preferably, the end of the first auxiliary tube is bent into an arc shape, and the first auxiliary tube is tangent to the connected fourth channel.

[0011] Preferably, the end of the second auxiliary tube is bent into an arc shape, and the second auxiliary tube is tangent to the connected first channel.

[0012] Preferably, the cross-sectional area of ​​the first channel is larger than that of the second channel, and the cross-sectional area of ​​the third channel is larger than that of the fourth channel.

[0013] Preferably, a first collecting pipe and a second collecting pipe are installed on both sides of the first pipeline and the second pipeline respectively, a first flange is installed at the end of the first collecting pipe, and a second flange is connected to the end of the second collecting pipe.

[0014] Beneficial effect: the exhaust gas flows in the same direction along the first pipeline and the second pipeline. When the exhaust gas flows forward in the first pipeline and the second pipeline, the exhaust gas at this time will not enter the first auxiliary pipe and the second auxiliary pipe. At this time, the engine EGR pipeline is in a conducting state, and the exhaust gas can flow smoothly; when the exhaust gas flows in the first pipeline and the second pipeline in the opposite direction, the exhaust gas in the first channel enters the fourth channel along the extended first auxiliary pipe and collides with the exhaust gas in the fourth channel, forming a blocking effect, preventing the exhaust gas from continuing to flow forward. Similarly, the exhaust gas in the fourth channel enters the first channel along the second auxiliary pipe and collides with the exhaust gas in the first channel, forming a blockage, preventing the exhaust gas from flowing forward. In this way, the exhaust gas in the first pipeline and the second pipeline mutually prevents the exhaust gas in the first pipeline and the second pipeline from continuing to flow forward, so that the exhaust gas in the engine EGR pipeline cannot flow forward, forming a blocking effect, realizing one-way conduction of the engine EGR pipeline, canceling the valve plate structure, and realizing one-way conduction of the engine EGR pipeline through the blocking effect. There will be no cylinder pulling problem, and the reliability is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the forward flow of exhaust gas in the EGR pipeline of the engine of the present invention;

[0016] Figure 2 It is a schematic diagram of the exhaust gas reverse flow in the EGR pipeline of the engine of the present invention;

[0017] Figure 3 It is the main body diagram of the engine EGR pipeline of the present invention.

[0018] In the figure: 1, first pipeline; 11, first channel; 12, second channel; 2, second pipeline; 21, third channel; 22, fourth channel; 3, first auxiliary pipe; 4, second auxiliary pipe; 5, first flange; 6, second flange; 7, first collecting pipe; 8, second collecting pipe. DETAILED DESCRIPTION

[0019] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0020] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0022] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0023] Under the existing technology, the valve plate in the engine EGR pipeline will bend and be damaged under repeated action. In this way, the metal residue on the valve plate will enter the engine cylinder with the exhaust gas, causing problems such as scratching the cylinder and reducing the service life of the engine.

[0024] In order to solve the above problems, Figures 1 to 3As shown, the present invention provides an engine EGR pipeline, comprising a first pipeline 1 and a second pipeline 2, the first pipeline 1 and the second pipeline 2 are parallel to each other, the first pipeline 1 is wavy, the first pipeline 1 comprises a first channel 11 and a second channel 12, the first channel 11 and the second channel 12 are alternately connected, the first channel 11 and the second channel 12 are connected in a V-shape, the second pipeline 2 is wavy, the second pipeline 2 comprises a third channel 21 and a fourth channel 22, the third channel 21 and the fourth channel 22 are alternately connected, the third channel 21 and the fourth channel 22 are connected in a V-shape; a first auxiliary pipe 3 is connected at a trough where the first channel 11 and the second channel 12 are connected, the first auxiliary pipe 3 extends in the direction of the first channel 11 and is connected to the fourth channel 22, and the other end of the first auxiliary pipe 3 is bent toward the second pipeline 2; a second auxiliary pipe 4 is connected at a crest where the third channel 21 and the fourth channel 22 are connected, the second auxiliary pipe 4 extends in the direction of the fourth channel 22 and is connected to the first channel 11, and the other end of the second auxiliary pipe 4 is bent toward the first pipeline 1.

[0025] The first pipeline 1 and the second pipeline 2 are placed in parallel and are interconnected by the first auxiliary pipe 3 and the second auxiliary pipe 4. The first pipeline 1 and the second pipeline 2 can be externally connected to a group of cylinders or the first cylinder and the second cylinder are respectively connected to two groups of cylinders; when the first pipeline 1 and the second pipeline 2 are simultaneously externally connected to the same group of cylinders, the first pipeline 1 and the second pipeline 2 are merged at both ends, and the first collecting pipe 7 and the second collecting pipe 8 are respectively formed at the two ends. The exhaust gas generated inside the engine is divided in the first pipeline 1 and the second pipeline 2 and finally merged or a blocking effect occurs, or the first pipeline 1 and the second pipeline 2 are independently connected to different cylinders, and the exhaust gas in different cylinders forms a blocking effect on each other or is discharged independently.

[0026] The exhaust gas flows in the first pipe 1 and the second pipe 2 in the engine EGR pipe at the same time, and the exhaust gas flows in the same direction. Figure 1 to Figure 2As shown, when the exhaust gas flows from the right side to the left side, it is a forward flow, and a conduction state needs to be achieved in the engine EGR pipeline. At this time, the exhaust gas in the first pipeline 1 flows along its own pipeline, and the exhaust gas in the second pipeline 2 flows along its own pipeline. At this time, the exhaust gas will not enter the first auxiliary pipe 3 and the second auxiliary pipe 4 with a larger bending angle due to inertia, and the exhaust gas flows out to the other side along the first pipeline 1 and the second pipeline 2 respectively; when the exhaust gas flows from the left side to the right side, the exhaust gas flows in the opposite direction, and the exhaust gas in the first channel 11 in the first pipeline 1 will enter the first auxiliary pipe 3 with its own inertia, and finally enter the fourth channel 22 in the second pipeline 2. At this time, the exhaust gas in the first auxiliary pipe 3 The exhaust gas collides with the exhaust gas in the fourth channel 22, forming resistance, preventing the exhaust gas from continuing to flow to the right. At the same time, the exhaust gas in the fourth channel 22 in the second pipeline 2 will enter the first channel 11 through the second auxiliary pipe 4, and collide with the exhaust gas flowing to the right in the first pipeline 1, blocking the exhaust gas in the first pipeline 1 from flowing to the right. The first auxiliary pipe 3 and the second auxiliary pipe 4 are alternately installed in the engine EGR pipeline to block the exhaust gas from further flowing to the right. Finally, the exhaust gas stops flowing to the right, realizing unidirectional cutoff of the engine EGR pipeline. The engine EGR pipeline adopted by the present invention does not have any moving parts inside, and only uses the first auxiliary pipe 3 and the second auxiliary pipe 4 to hinder the flow of exhaust gas, so the reliability is higher.

[0027] The wavy first pipe 1 and the second pipe 2 can make the first auxiliary pipe 3 and the second auxiliary pipe 4 extend a shorter distance and bend at a smaller curvature at the end, so as to maintain the flow velocity of the exhaust gas in the first auxiliary pipe 3 and the second auxiliary pipe 4, and form an arc at the junction of the first channel 11 and the second channel 12, so that the airflow can flow more smoothly, and when the exhaust gas flows forward in the engine EGR pipe, the exhaust gas can flow more smoothly. At the same time, the angle between the first channel 11 and the second channel 12 is an obtuse angle, and the speed lost by the exhaust gas is reduced during the turning process of the airflow at the obtuse angle position.

[0028] The third channel 21 and the fourth channel 22 are connected in an arc shape, so that the airflow can flow more smoothly, and when the exhaust gas flows forward in the engine EGR pipe, the exhaust gas can flow more smoothly. At the same time, the angle between the third channel 21 and the fourth channel 22 is an obtuse angle, which reduces the speed loss of the exhaust gas during the turning process of the airflow at the obtuse angle.

[0029] The end of the first auxiliary pipe 3 is bent into an arc shape, so that the exhaust gas will not lose speed when flowing in the first auxiliary pipe 3. The exhaust gas has enough momentum to collide with the exhaust gas in the second pipe 2, thereby blocking the exhaust gas in the second pipe 2 from continuing to flow in the opposite direction. The first auxiliary pipe 3 is tangent to the connected fourth channel 22, so that the exhaust gas in the first auxiliary pipe 3 can collide with the exhaust gas in the second pipe 2 in a nearly opposite direction, thereby blocking the exhaust gas from continuing to flow to the right to the greatest extent.

[0030] The end of the second auxiliary pipe 4 is bent into an arc shape, so that the exhaust gas will not lose speed when flowing in the second auxiliary pipe 4. The exhaust gas has enough momentum to collide with the exhaust gas in the first pipeline 1, thereby blocking the exhaust gas in the first pipeline 1 from continuing to flow in the opposite direction. The second auxiliary pipe 4 is tangent to the connected first channel 11, so that the exhaust gas in the second auxiliary pipe 4 can collide with the exhaust gas in the first pipeline 1 in a nearly opposite direction, thereby blocking the exhaust gas from continuing to flow to the right to the greatest extent.

[0031] The cross-sectional area of ​​the first channel 11 is larger than that of the second channel 12, so that when the exhaust gas flows in reverse to the trough of the first pipeline 1, most of the exhaust gas can enter the first auxiliary pipe 3, blocking the exhaust gas in the second pipeline 2 from flowing forward. Similarly, the cross-sectional area of ​​the third channel 21 is larger than that of the fourth channel 22, so that when the exhaust gas flows to the peak in the second pipeline 2, it can all enter the second auxiliary pipe 4, so that the exhaust gas can completely block the exhaust gas in the first pipeline 1 from flowing in reverse, so that the engine EGR pipeline of the present invention has a better blocking effect, and when the exhaust gas flows in reverse, it can be completely blocked by the engine EGR pipeline.

[0032] A first collecting pipe 7 and a second collecting pipe 8 are respectively installed on both sides of the first pipeline 1 and the second pipeline 2. A first flange 5 is installed at the end of the first collecting pipe 7, and a second flange 6 is connected to the end of the second collecting pipe 8. The engine EGR pipeline can be installed before or after the EGR cooler through the first flange 5 and the second flange 6, and can be flexibly adjusted according to design requirements.

[0033] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An engine EGR pipeline, characterized in that: The invention comprises a first pipeline (1) and a second pipeline (2), the first pipeline (1) and the second pipeline (2) are parallel to each other, the first pipeline (1) is wavy, the first pipeline (1) comprises a first channel (11) and a second channel (12), the first channel (11) and the second channel (12) are alternately connected, the first channel (11) and the second channel (12) are connected in a V-shape, the second pipeline (2) is wavy, the second pipeline (2) comprises a third channel (21) and a fourth channel (22), the third channel (21) and the fourth channel (22) are alternately connected, the third channel (21) and the fourth channel (22) are alternately connected, The fourth channel (22) is connected in a V-shape; a first auxiliary pipe (3) is connected at the trough where the first channel (11) and the second channel (12) meet, the first auxiliary pipe (3) extends in the direction of the first channel (11) and is connected to the fourth channel (22), and the other end of the first auxiliary pipe (3) is bent toward the second pipeline (2); a second auxiliary pipe (4) is connected at the crest where the third channel (21) and the fourth channel (22) meet, the second auxiliary pipe (4) extends in the direction of the fourth channel (22) and is connected to the first channel (11), and the other end of the second auxiliary pipe (4) is bent toward the first pipeline (1).

2. The engine EGR pipeline according to claim 1, characterized in that: The junction between the first channel (11) and the second channel (12) is arc-shaped.

3. The engine EGR pipeline according to claim 2, characterized in that: The angle between the first channel (11) and the second channel (12) is an obtuse angle.

4. The engine EGR pipeline according to claim 1, characterized in that: The junction between the third channel (21) and the fourth channel (22) is arc-shaped.

5. The engine EGR pipeline according to claim 4, characterized in that: The angle between the third channel (21) and the fourth channel (22) is an obtuse angle.

6. The engine EGR pipeline according to claim 1, characterized in that: The end of the first auxiliary tube (3) is bent into an arc shape, and the first auxiliary tube (3) is tangent to the connected fourth channel (22).

7. The engine EGR pipeline according to claim 1, characterized in that: The end of the second auxiliary tube (4) is bent into an arc shape, and the second auxiliary tube (4) is tangent to the connected first channel (11).

8. The engine EGR pipeline according to claim 1, characterized in that: The cross-sectional area of ​​the first channel (11) is greater than the cross-sectional area of ​​the second channel (12), and the cross-sectional area of ​​the third channel (21) is greater than the cross-sectional area of ​​the fourth channel (22).

9. The engine EGR pipeline according to claim 1, characterized in that: A first collecting pipe (7) and a second collecting pipe (8) are respectively installed on both sides of the first pipeline (1) and the second pipeline (2); a first flange (5) is installed at the end of the first collecting pipe (7), and a second flange (6) is connected to the end of the second collecting pipe (8).

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