A catalyst structure with heat preservation function during cold start

Abstract

The present invention provides a catalyst structure with a heat preservation function during cold start, including an inner shell and an outer shell, wherein the two ends of the inner shell are respectively provided with an air inlet and an air outlet, and the inner shell is also provided with a first air inlet hole and a first air outlet hole, and a baffle is provided between the first air outlet hole and the first air inlet hole, and the baffle is not arranged parallel to the direction of the airflow; the outer shell includes a guide tube and a sealing tube, the length of the guide tube is smaller than the sealing tube, and a gap is provided between the outer wall of the guide tube and the outer wall of the sealing tube, and a silencer hole is provided on the guide tube. The outer shell acts as a heat preservation layer so that the inner shell is not in direct contact with the air, and the outer shell includes a sealing tube and a guide tube, and the direction of the airflow is extended by the guide tube, so that the airflow has to pass a relatively long distance in the outer shell before it can flow out. During cold start, the ignition time of the catalyst in the inner shell can be shortened, the catalyst reaction is promoted, and the emission of pollutants is reduced. It can also play a role in noise reduction.

Description

Technical Field

[0001] The invention relates to the technical field of mufflers, and in particular to a catalyst structure with a heat preservation function during cold start. Background Art

[0002] The automotive catalytic converter is a packaged structure with a fixed catalyst, most of which are cylindrical in shape, and use a gasket to fix and package the catalyst. When the high-temperature exhaust gas discharged by the engine flows through the catalyst shell, it is catalytically converted by the internal catalyst and then directly discharged into the muffler and finally into the atmosphere.

[0003] At present, the housing of automobile catalytic converters generally adopts a simple cylindrical structure to encapsulate the catalyst and fix the catalyst with a gasket. The high-temperature and high-flow exhaust gas is directly discharged into the muffler after catalytic conversion by the catalyst, which will have the following defects:

[0004] 1. After the vehicle is cold started, the temperature of the entire exhaust system is low. The heat of the high-temperature gas discharged by the engine is absorbed by the pipeline. When the exhaust gas flows to the catalyst, the temperature is reduced, which cannot meet the conditions for the catalyst to perform catalytic conversion, resulting in a large amount of exhaust gas pollutants being directly discharged into the atmosphere;

[0005] 2. The catalyst housing is in direct contact with the atmosphere, transferring heat to the atmosphere, which causes the catalyst temperature to rise for a longer time when the vehicle is cold started, which is not conducive to the catalytic conversion of pollutants;

[0006] 3. High-speed, high-flow gas flows directly downstream after passing through the catalyst, increasing the volume of the muffler and the difficulty of tuning.

[0007] Therefore, the existing cylindrical catalyst structure is not conducive to shortening the catalyst ignition time and reducing pollutant emissions during cold start of the automobile, and also does not play a role in assisting in reducing exhaust noise. Summary of the invention

[0008] The present invention aims at the problem that when a car is cold started, the exhaust gas from the engine passes through the catalyst, and the catalyst is in direct contact with the atmosphere, resulting in heat loss. The catalyst temperature in the catalyst is not high enough to meet the conditions for catalytic conversion, thereby causing the exhaust gas to be directly discharged into the atmosphere to pollute the environment. The present invention provides a catalyst structure with a heat preservation function during cold start.

[0009] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0010] A catalyst structure with a heat preservation function during cold start, comprising an inner shell and an outer shell, wherein two ends of the inner shell are respectively provided with an air inlet and an air outlet, and the inner shell is also provided with a first air inlet hole and a first air outlet, and a baffle is provided between the first air outlet and the first air inlet hole, and the baffle is not arranged parallel to the direction of the airflow; the outer shell comprises a guide tube and a sealing tube, the guide tube is located in the sealing tube, and the inner shell is located in the guide tube, the length of the guide tube is smaller than the sealing tube, a gap is provided between the outer wall of the guide tube and the outer wall of the sealing tube, and the two ends of the sealing tube are sealed with the inner shell, a silencer hole is provided on the guide tube, and the first air outlet is located between the guide tube and the sealing tube, and the first air outlet is close to one end of the air outlet.

[0011] Preferably, the end of the guide tube close to the air inlet is connected to the end of the sealing tube, the first air inlet hole is close to one side of the air outlet, the first air inlet hole is far away from the air inlet, the first air inlet hole is located in the guide tube, and the silencer hole is close to one side of the air inlet. In this way, the path of the gas in the shell can be extended, which is helpful for heat preservation.

[0012] Preferably, it also includes an airflow control mechanism, which is connected to the baffle and is used to control the angle of the baffle. The airflow control mechanism is used to prevent the exhaust gas from flowing directly from the air inlet to the air outlet during the cold start stage. In order to prevent the exhaust gas from flowing directly from the air inlet of the inner shell to the air outlet during the cold start stage, the gas is blocked by the baffle so that the gas can be blocked by the baffle after flowing in from the air inlet. After starting for a period of time, the temperature inside the inner shell has reached the ignition temperature. The airflow control mechanism can control the angle of the baffle, and the catalytic conditions of the gas in the inner shell are reached. The gas does not pass through the outer shell but only flows out from the air inlet of the inner shell after the catalyst acts on it, which can also catalyze the exhaust gas. After the cold start, if the exhaust gas is not discharged in time, the temperature inside the inner shell will be too high and the heat cannot be dissipated.

[0013] Preferably, the airflow control mechanism includes a baffle, a rotating rod and a flow controller, the baffle is fixedly connected to the rotating rod, the baffle is located between the first air inlet and the first air outlet, the baffle is located at the end of the guide tube away from the air inlet, one end of the rotating rod passes through the sealing tube and is connected to the controller, the other end of the rotating rod passes through the inner shell, the rotating rod is rotatably connected to the inner shell, the controller is used to control the angle between the baffle and the inner shell, and an airflow control hole is provided on one side of the baffle. There is an airflow control hole on one side of the baffle and not on the other side. After the airflow flows in, the force on both sides of the baffle is different, which will apply a force to the rotating rod, which is detected by the flow controller, so the flow controller can control the rotation of the rotating rod. The flow controller can adjust the rotation angle of the airflow baffle according to the airflow force acting on the baffle, change the flow direction and channel of the airflow, reduce the airflow energy, and play an auxiliary noise reduction role.

[0014] Preferably, the inner shell includes an inflow section, an expansion section, a main section, a contraction section and an outflow section, the air inlet is arranged in the inflow section, the air outlet is arranged in the outflow section, the cross section of the expansion section gradually increases from the inflow section to the main section, and the cross section of the contraction section gradually decreases from the main section to the outflow section. From the direction of the airflow, the diameter of the expansion section gradually increases, and the diameter of the contraction section becomes smaller and smaller, and the airflow is reflected and interfered in the expansion section and the contraction section, so that the exhaust noise can be detected.

[0015] Compared with the prior art, the invention has the following beneficial effects: the invention provides an outer shell outside the inner shell, and the outer shell acts as a heat-insulating layer so that the inner shell is not in direct contact with the air, and the outer shell includes a sealing cylinder and a guide cylinder, and the direction of the airflow is extended by the guide cylinder, so that the airflow has to pass a relatively long distance in the outer shell before it can flow out. During cold start, the airflow flowing in the outer shell prevents the heat loss of the inner shell, which can shorten the ignition time of the catalyst in the inner shell, promote the catalyst reaction, and thus reduce the emission of pollutants. And the noise reduction in the enclosed space also has a certain effect, which can play a role in noise reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the structure of the catalyst provided by the present invention;

[0017] Figure 2 for Figure 1 A cross-sectional view of

[0018] Figure 3 is a schematic diagram of the structure of the shell;

[0019] Figure 4 for Figure 3 A cross-sectional view of

[0020] Figure 5is a schematic diagram of the structure of the inner shell;

[0021] Figure 6 It is a structural schematic diagram of the airflow control mechanism.

[0022] Markings in the figure: 1-inner shell, 2-outer shell, 3-baffle, 4-air inlet, 5-air outlet, 6-first air inlet hole, 7-first air outlet hole, 8-guide tube, 9-sealing tube, 10-silencer hole, 11-air flow control mechanism, 12-rotating rod, 13-flow controller, 14-air flow control hole, 18-inflow section, 19-expansion section, 20-contraction section, 21-outflow section, 22-first cavity, 23-second cavity, 24-third cavity, 25-fourth cavity, 26-main section. DETAILED DESCRIPTION

[0023] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0024] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0025] In the description of the present invention, it is necessary to understand that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0026] In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal connection between two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0027] like Figures 1 to 6 As shown, the present application provides a catalyst structure with a heat preservation function during cold start, comprising an inner shell 1 and an outer shell 2, wherein the outer shell 2 is sleeved outside the inner shell 1.

[0028] An air inlet 4 and an air outlet 5 are respectively disposed at two ends of the inner shell 1 , and a first air inlet hole 6 and a first air outlet hole 7 are also disposed on the inner shell 1 .

[0029] like Figure 2 He Ru Figure 5 As shown, the inner shell 1 includes an inflow section 18, an expansion section 19, a main section 26, a contraction section 20 and an outflow section 21, the air inlet 4 is arranged in the inflow section 18, the air outlet 5 is arranged in the outflow section 21, the cross-section of the expansion section 19 gradually increases from the inflow section 18 to the main section 26, and the cross-section of the contraction section 20 gradually decreases from the main section 26 to the outflow section 21.

[0030] The main body section 26 is entirely located inside the outer shell 2, and the intersections of the two ends of the outer shell 2 and the inner shell 1 are exactly the intersections of the expansion section 19 and the main body section 26, and the intersections of the contraction section 20 and the main body section 26. The first air inlet 6 and the first air outlet 7 are both located on the main body section 26, and the first air inlet 6 and the first air outlet 7 are both arranged close to the side of the air outlet 5, which is equivalent to the gas first passing through the path of most of the length of the main body section 26, and then reporting to the inner shell 1 in the reverse direction of the outflow, so as to better keep the inner shell 1 warm.

[0031] The main body section 26 is a cylindrical structure, and the first air inlet holes 6 and the first air outlet holes 7 are arranged regularly around the circumference of the cylinder.

[0032] A baffle 3 is provided between the first air outlet 7 and the first air inlet 6, and the baffle 3 is not arranged parallel to the direction of the airflow. The baffle 3 is connected to an airflow control mechanism 11 for controlling the angle of the baffle 3, and the airflow control mechanism 11 is used to prevent the exhaust gas from flowing directly from the air inlet 4 to the air outlet 5 during the cold start stage.

[0033] A rotating rod 12 is installed in the middle of the baffle 3. After the rotating rod 12 passes through the inner shell 1, it is rotatably arranged with the inner shell 1, so that the entire baffle 3 can rotate relative to the inner shell 1. A flow controller 13 is connected to the top of the rotating rod 12, and the outer shell 2 of the flow controller 13 is fixed on the outer shell 2. The baffle 3 takes the rotating rod 12 as the central axis, and an airflow control hole 14 is provided on one side of the central axis, and there is no hole on the other side. In this way, the airflow exerts different forces on the baffles 3 on both sides of the central axis after flowing in, which will apply a torsional force to the baffle 3. After the flow controller 13 detects the torque, it compares it with the preset value, and then controls the baffle 3, for example, through a motor, to control the angle between the baffle 3 and the inner shell 1. In the initial stage, the airflow of the baffle 3 is vertically arranged, which is equivalent to the baffle 3 being relatively vertical to the inner shell 1.

[0034] The outer shell 2 includes a flow guide cylinder 8 and a sealing cylinder 9 . The flow guide cylinder 8 is located inside the sealing cylinder 9 , and the inner shell 1 is located inside the flow guide cylinder 8 .

[0035] The length of the guide tube 8 is smaller than that of the sealing tube 9 , and both ends of the sealing tube 9 are welded to the inner shell 1 .

[0036] A gap is provided between the outer wall of the guide tube 8 and the outer wall of the sealing tube 9, and both ends of the sealing tube 9 are sealed and connected to the inner shell 1. A muffler hole 10 is provided on the guide tube 8, and the first air outlet hole 7 is located between the guide tube 8 and the sealing tube 9, and the first air outlet hole 7 is close to one end of the air outlet 5. The end of the guide tube 8 close to the air inlet 4 is connected to the end of the sealing tube 9, the first air inlet hole 6 is close to one side of the air outlet 5, the first air inlet hole 6 is far away from the air inlet 4, the first air inlet hole 6 is located in the guide tube 8, and the muffler hole 10 is close to one side of the air inlet 4.

[0037] like Figure 2 and Figure 4 As shown, the cross section of the guide tube 8 is L-shaped, and the guide tube 8 is welded to the top of the sealing tube 9 on one side of the air inlet 4. The middle of the end of the guide tube 8 close to the air outlet 5 is hollow for the inner shell 1 to pass through, and the rotating rod 12 passes through the sealing tube 9. The rotating rod 12 can pass through the guide tube 8 or be located outside the guide tube 8. In this embodiment, the rotating rod 12 is located outside the guide tube 8.

[0038] The main section 26 of the inner shell 1 forms a first cavity 22 from the air inlet 4 to the baffle 3, a second cavity 23 is formed between the guide tube 8 and the main section 26, a third cavity 24 is formed between the guide tube 8, the sealing tube 9 and the main section 26 near one end of the air outlet, and a fourth cavity 25 is formed between the baffle 3 and the main section 26 near the air outlet 5. A catalyst is installed in the main section 26.

[0039] Working process: Figure 2 As shown, during the cold start phase, the gas flows in from right to left through the air inlet 4, and the expansion section 19 reflects and interferes with the gas to reduce noise, and then the gas flows into the first cavity 22. After being catalyzed by the catalyst, the gas passes through the baffle 3, and part of the gas passes through the first air inlet 6 and enters the second cavity 23, and then flows to the right in the opposite direction, passes through the silencer hole 10 to enter the third cavity 24 and flows to the left, and then passes through the first air outlet 7 to enter the fourth cavity 25, and finally flows out through the air outlet 5. Starting from the inner shell 1 today, the gas is equivalent to flowing three times in the main section 26 of the inner shell 1, namely the first cavity 22, the second cavity 23 and the third cavity 24, thereby playing a role in heat preservation for the inner shell 1 during the cold start phase. At the same time, when the gas passes through the silencer hole 10, it plays a role in noise reduction and silencing.

[0040] Since an airflow control hole 14 is provided on one side of the baffle 3, the force exerted by the gas on both sides of the baffle 3 is different, which will apply a torsional force to the rotating rod 12. The flow controller 13 detects the torsional force of the rotating rod 12, and then compares it with the preset force, and then controls the rotation of the rotating rod 12 to control the angle between the baffle 3 and the inner shell 1. After the cold start stage, the temperature inside the inner shell 1 rises, and the catalyst ignition condition in the inner shell 1 is reached. In order to allow the gas to flow out smoothly and reduce the temperature of the inner shell 1, the flow controller 13 can control the baffle 3 to be consistent with the direction of the airflow, so that the airflow does not pass through the outer shell 2.

[0041] Through the catalyst structure provided by the present application, the high-temperature exhaust gas discharged during the cold start phase of the vehicle is guided through the baffle 3 and enters the guide tube 8 through the first air inlet 6, heating and insulating the outer surface of the inner shell 1, reducing the ignition time of the catalyst, promoting the catalyst reaction, thereby reducing the emission of pollutants, and helping to control the development cost of the catalyst. A circuitous cavity is formed in the outer shell 2, and there are silencer holes inside, which can effectively reduce the airflow noise while guiding the flow. The airflow control mechanism 11 can adjust the rotation angle of the baffle according to the airflow force acting on the baffle 3, change the flow direction and channel of the airflow, reduce the airflow energy, and play an auxiliary noise reduction role. The baffle 3 rotates to an appropriate angle according to the difference in gas flow and all airflow forces of the two equally divided planes of the baffle, and divides the inner shell into two changing inner cavities, which can effectively reduce the noise of different frequency bands, thereby simplifying the internal structure and volume of the muffler, reducing the difficulty of tuning the muffler, and reducing the development cost of the muffler.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. 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 present invention.

Claims

1. A catalyst structure having a heat preservation function during cold start, characterized in that: The invention comprises an inner shell (1) and an outer shell (2), wherein the outer shell (2) is sleeved on the outer shell (1), an air inlet (4) and an air outlet (5) are respectively provided at two ends of the inner shell (1), and the inner shell (1) is also provided with a first air inlet hole (6) and a first air outlet hole (7), a baffle (3) is provided between the first air outlet hole (7) and the first air inlet hole (6), and the baffle (3) is arranged not parallel to the direction of the air flow; the outer shell (2) comprises a guide tube (8) and a sealing tube (9), the guide tube (8) is located inside the sealing tube (9), and the inner shell (1) is located inside the guide tube (8), the length of the guide tube (8) is smaller than that of the sealing tube (9), and the outer wall of the guide tube (8) is parallel to the sealing tube (9). A gap is provided between the outer walls of the sealing cylinder (9), the two ends of the sealing cylinder (9) are sealedly connected to the inner shell (1), the guide cylinder (8) is provided with a silencer hole (10), the first air outlet hole (7) is located between the guide cylinder (8) and the sealing cylinder (9), the first air outlet hole (7) is close to one end of the air outlet (5), the end of the guide cylinder (8) close to the air inlet (4) is connected to the end of the sealing cylinder (9), the first air inlet hole (6) is close to one side of the air outlet (5), the first air inlet hole (6) is far away from the air inlet (4), the first air inlet hole (6) is located in the guide cylinder (8), and the silencer hole (10) is close to one side of the air inlet (4).

2. The catalyst structure according to claim 1, characterized in that: It also includes an airflow control mechanism (11), which is connected to the baffle (3) and is used to control the angle of the baffle (3). The airflow control mechanism (11) is used to prevent the exhaust gas from flowing directly from the air inlet (4) to the air outlet (5) during the cold start phase.

3. The catalyst structure according to claim 2, characterized in that: The airflow control mechanism (11) comprises a rotating rod (12) and a flow controller (13); a baffle (3) is fixedly connected to the rotating rod (12); the baffle (3) is located between the first air inlet (6) and the first air outlet (7); the baffle (3) is located at one end of the guide tube (8) away from the air inlet (4); one end of the rotating rod (12) passes through the sealing tube (9) and is connected to the controller; the other end of the rotating rod (12) passes through the inner shell (1); the rotating rod (12) is rotatably connected to the inner shell (1); the controller is used to control the angle between the baffle (3) and the inner shell (1); and an airflow control hole (14) is provided on one side of the baffle (3).

4. The catalyst structure according to claim 1, characterized in that: The inner shell (1) comprises an inflow section (18), an expansion section (19), a main body section (26), a contraction section (20) and an outflow section (21); the air inlet (4) is arranged in the inflow section (18), the air outlet (5) is arranged in the outflow section (21); the cross section of the expansion section (19) gradually increases from the inflow section (18) to the main body section (26), and the cross section of the contraction section (20) gradually decreases from the main body section (26) to the outflow section (21).

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