Exhaust silencing device, power device, vehicle and flow control valve

Abstract

The embodiment of the invention provides an exhaust silencing device, a power device, a vehicle and a flow control valve. Relates to the technical field of silencing. The problem that noise is generated in the exhaust process of an engine is mainly solved. The flow control valve is arranged at the first exhaust port of the first exhaust pipe, and when gas is conveyed in the first exhaust pipe, the turning plate connected with the first exhaust pipe can prevent the gas from flowing, so that the exhaust back pressure is improved. The exhaust back pressure is increased, so that the resistance to gas flowing is increased, the gas flowing speed is reduced, the pressure fluctuation amplitude of gas in the first exhaust pipe can be reduced, sound energy transmitted in unit time is reduced, and noise is lowered. When the rotating speed of the engine is increased, the gas pressure is increased, the opening degree of the turning plate is increased, in the process, the elastic reset piece can provide elastic force for the turning plate, under the action of the elastic force, the turning plate tends to reset, and therefore appropriate exhaust back pressure is provided, and the noise problem is relieved.

Description

Technical Field

[0001] This application relates to the field of noise reduction technology, and in particular to an exhaust noise reduction device, a power unit, a vehicle, and a flow control valve. Background Technology

[0002] The engine is the core power unit of a car, affecting its power output and performance. Essentially, an engine is an energy conversion device; its core function is to convert the chemical energy of fuel (gasoline, fuel oil, etc.) into mechanical energy. This energy conversion process is achieved through the combustion cycle. Through this cycle, the engine continuously converts the chemical energy of fuel into mechanical energy, driving the wheels and enabling the car to move.

[0003] When an engine is running, the combustible mixture burns at high temperature and pressure in a very short time. After the exhaust valve opens, the gases produced during combustion generate noise as they are transmitted through the exhaust system. This noise not only seriously disturbs the environment but also causes irreversible damage to human health. Summary of the Invention

[0004] This application provides an exhaust muffler, a power unit, a vehicle, and a flow control valve for mitigating noise generated during engine exhaust.

[0005] To achieve the above objectives, this application adopts the following technical solution: One aspect of this application provides an exhaust silencing device, which includes a first housing, a partition, a first exhaust pipe, a second exhaust pipe, and a flow control valve. The partition is located within the first housing and divides the first housing into at least two cavities. Multiple silencing holes are formed in the partition. A first air inlet of the first exhaust pipe extends out of the first housing, and a first exhaust outlet of the first exhaust pipe is located within the first housing and penetrates the partition. A second air inlet of the second exhaust pipe is located within the first housing and penetrates the partition. A second exhaust outlet of the second exhaust pipe extends out of the first housing. The first exhaust outlet and the second air inlet are located in different cavities. The flow control valve includes a flap and a resilient reset member. The flap is connected to the first exhaust pipe. One end of the resilient reset member is connected to the first exhaust pipe, and the other end is connected to the flap. The resilient reset member is used to, in an initial state, cover at least a portion of the exhaust passage of the first exhaust pipe with the flap.

[0006] The first intake port of the first exhaust pipe receives gas discharged from other components connected to the exhaust muffler. This gas, after passing through the first exhaust pipe, is discharged into the cavity containing the first exhaust port. Because a flow control valve is installed at the first exhaust port of the first exhaust pipe, a flap connected to the first exhaust pipe can impede the gas flow during gas transmission, thereby increasing the exhaust back pressure. This increased exhaust back pressure increases the resistance to gas flow, leading to a decrease in gas flow velocity, which in turn reduces the pressure fluctuation amplitude within the first exhaust pipe. Since the gas can propagate in pulses, these gas pulses can excite vibrations in the air medium and propagate through the first exhaust pipe with the surrounding air, forming sound waves. When the pressure fluctuation amplitude within the first exhaust pipe decreases, less sound energy is transmitted per unit time, reducing noise. As the engine speed increases, the gas pressure rises, causing the flap opening to increase. During this increase, the elastic reset component provides an elastic force to the flap, causing it to tend to reset, thus slowing down the change in flap opening amplitude, providing appropriate exhaust back pressure, and further mitigating noise issues.

[0007] Furthermore, since the first exhaust port and the second air inlet are located in different cavities via a partition, gas from the first exhaust port can pass through the silencer holes on the partition to the second air inlet and then be discharged into the atmosphere through the second exhaust pipe. Gas can propagate in pulses within the first exhaust pipe. The aforementioned partition, cavity, and other structures cause destructive reflection of sound waves and abrupt changes in the acoustic impedance, gradually attenuating sound energy and thus reducing noise. During the gas's passage through the silencer holes, the original strong pulsed high-pressure airflow is transformed into a dispersed low-pressure airflow, further reducing noise.

[0008] In one possible implementation, the flow control valve is located outside the first exhaust pipe. A flap is located at the end where the first exhaust port is located, and the flap is hinged to the first exhaust pipe. Because the flap is hinged to the first exhaust pipe, it facilitates a more rotatable connection between the flap and the first exhaust pipe.

[0009] In one possible implementation, the flow control valve further includes a mounting ring, at least a portion of which is nested at the first exhaust port and connected to the first exhaust pipe. A portion of a flap is hinged to the mounting ring. When the flap is indirectly connected to the first exhaust pipe via the mounting ring, the contact area between the mounting ring and the first exhaust pipe can be increased, thereby improving installation reliability.

[0010] In one possible implementation, the flow control valve further includes a first rotating shaft. A first exhaust pipe is rotatably connected to the first rotating shaft, and a flap is also rotatably connected to the first rotating shaft. The elastic reset element includes a first spring. The first rotating shaft passes through the first spring. The third end of the first spring is connected to the first exhaust pipe, and the fourth end of the first spring is connected to the flap. Because the first exhaust pipe and the flap are rotatably connected to the first rotating shaft, the flap can rotate relative to the first exhaust pipe via the first rotating shaft. Furthermore, because the third end of the first spring is connected to the first exhaust pipe, and the fourth end is connected to the flap, a force can be applied to both ends of the first spring during the rotation of the flap relative to the first exhaust pipe, causing the first spring to undergo elastic deformation matching the flap opening. This elastic deformation generates an elastic force, which reacts on the flap to control the flip angle of the flap relative to the first exhaust pipe, i.e., the flap opening. This reduces the amplitude of the flap opening change, allowing the flow control valve to provide appropriate exhaust back pressure, thereby mitigating noise issues.

[0011] In one possible implementation, the elastic reset element includes a spring. A first end of the spring is connected to a first exhaust pipe, and a second end is connected to a flap. Since the flap is hinged to the first exhaust pipe, it can rotate relative to the first exhaust pipe. Furthermore, because the first end of the spring is connected to the first exhaust pipe and the second end to the flap, forces can be applied to both ends of the spring during the flap's rotation relative to the first exhaust pipe. This causes the spring to undergo elastic deformation matching the flap's opening degree. The elastic deformation generates an elastic force that reacts on the flap to control its tilt angle relative to the first exhaust pipe, i.e., the flap's opening degree. This reduces the amplitude of the flap opening change, allowing the flow control valve to provide appropriate exhaust back pressure, thereby mitigating noise issues.

[0012] In one possible implementation, the flap is located inside the first exhaust pipe and is hinged to the first exhaust pipe. Because the flap is located inside the first exhaust pipe, it can provide exhaust back pressure while reducing the volume occupied inside the first housing.

[0013] In one possible implementation, the flow control valve further includes a second shaft that is arranged intersecting the extension direction of the first exhaust pipe. The second shaft includes a first portion and a second portion. The first portion is located inside the first exhaust pipe and connected to a flap. The second portion extends out of the first exhaust pipe. The resilient reset element includes a second spring. The second portion passes through the second spring. One end of the second spring is connected to the first exhaust pipe, and the other end of the second spring is connected to the end of the second portion opposite to the first portion.

[0014] Since the first part of the second rotating shaft is located inside the first exhaust pipe and is connected to the flap, the flap is positioned inside the first exhaust pipe. Furthermore, since the second part of the second rotating shaft extends out of the first exhaust pipe, and a second spring passes through the second rotating shaft, one end of the second spring is connected to the first exhaust pipe, and the other end is connected to the end of the second part opposite to the first part. Therefore, during the rotation of the flap relative to the first exhaust pipe, forces can be applied to both ends of the second spring, causing the second spring to undergo elastic deformation matching the change in flap opening. This elastic deformation generates an elastic force, which reacts on the flap to control the flap's rotation angle relative to the first exhaust pipe, i.e., the flap opening. This reduces the amplitude of flap opening changes, allowing the flow control valve to provide appropriate exhaust back pressure. Consequently, the pressure fluctuation amplitude inside the first exhaust pipe decreases, reducing the amount of sound energy transmitted per unit time, thus mitigating noise problems.

[0015] In one possible implementation, the flap comprises a third and a fourth section. A second pivot is located between the third and fourth sections. The third and fourth sections are symmetrically arranged about the second pivot. In actual installation, compared to an asymmetrical arrangement of the third and fourth sections about the second pivot, the symmetrical arrangement of the third and fourth sections, with the second pivot passing through the axis of the first exhaust pipe, makes actual machining and installation easier.

[0016] In one possible implementation, the flow control valve further includes a first motor located within a first housing. The output shaft of the first motor is connected to a second rotating shaft, which drives the second rotating shaft to rotate, thereby controlling the opening degree of the flap. Because the output shaft of the first motor is connected to the second rotating shaft, the flap opening degree can be automatically adjusted by the first motor, thereby dynamically adjusting the exhaust back pressure.

[0017] In one possible implementation, the flap is made of heat-resistant steel, stainless steel, or other metal materials. Since the exhaust temperature is typically 100-300 degrees Celsius, using heat-resistant steel, stainless steel, or other metal materials for the flap ensures high temperature resistance and allows for welding connections during installation, thus improving the reliability of the exhaust flow valve.

[0018] In another aspect, this application provides a power unit comprising any of the exhaust muffler devices and an engine as described above. The engine includes a cylinder head. A first exhaust passage on the cylinder head is connected to a first air inlet of a first exhaust pipe in the exhaust muffler. When the engine in the power unit operates, it generates gas, which is transmitted through the first exhaust passage on the cylinder head to the exhaust muffler for noise reduction. This power unit has the same technical effects as the exhaust muffler device provided in the foregoing embodiments, and will not be described again here.

[0019] In one possible implementation, the flow control valve in the exhaust muffler includes a first motor, the output shaft of which is connected to a second rotating shaft of the flow control valve. The first motor drives the second rotating shaft to rotate. The power unit also includes a first controller. The first controller is electrically connected to the first motor and the engine. The first controller acquires the engine speed and controls the rotation of the first motor's output shaft based on the speed, thereby controlling the opening of the flap. Since the first controller is electrically connected to the first motor and the engine, after acquiring the engine speed, it controls the rotation of the first motor's output shaft. The first motor's output shaft is connected to the second rotating shaft of the flow control valve, and the rotation of the first motor's output shaft drives the second rotating shaft to rotate, thus controlling the opening of the flap. In this way, the first motor automatically adjusts the flap opening based on the engine speed, thereby dynamically adjusting the exhaust back pressure.

[0020] In one possible implementation, the power unit also includes an intake manifold and a pressure sensor. The exhaust port of the intake manifold is connected to a first intake passage on the cylinder head. The pressure sensor is mounted on the intake manifold and is used to detect gas pressure. The flow control valve in the exhaust muffler includes a first motor, the output shaft of which is connected to a second rotating shaft of the flow control valve. The first motor drives the second rotating shaft to rotate. The power unit also includes a second controller. The second controller is electrically connected to the first motor and the pressure sensor. The second controller acquires the detection data from the pressure sensor and controls the rotation of the first motor's output shaft based on the detection data, thereby controlling the opening degree of the flap. Because the second controller is electrically connected to the first motor and the pressure sensor, after acquiring the gas pressure data detected by the pressure sensor, it controls the rotation of the first motor's output shaft. Since the first motor's output shaft is connected to the second rotating shaft of the flow control valve, the rotation of the first motor's output shaft drives the second rotating shaft to rotate, thus controlling the opening degree of the flap. In this way, based on the gas pressure data, the first motor automatically adjusts the flap opening, thereby dynamically adjusting the exhaust back pressure.

[0021] In another aspect, this application provides a vehicle comprising any of the power units described above and a second housing, with at least a portion of the power unit located within the second housing. The second housing protects the power unit and also serves to decorate and reduce the ingress of external moisture and dust into the interior of the second housing. This vehicle has the same technical effects as the power unit provided in the foregoing embodiments, and will not be repeated here.

[0022] In another aspect, this application provides a flow control valve for connection to a first exhaust pipe. The flow control valve includes a flap and a resilient reset member. The flap is hinged to the first exhaust pipe. One end of the resilient reset member is connected to the first exhaust pipe, and the other end is connected to the flap. The resilient reset member is used to cover at least a portion of the exhaust passage of the first exhaust pipe with the flap in an initial state.

[0023] Gas from the first intake port passes through the first exhaust pipe and is discharged into the cavity containing the first exhaust port. Because a flow control valve is installed at the first outlet of the first exhaust pipe, a flap connected to the first exhaust pipe can impede the gas flow during gas transmission, thereby increasing the exhaust back pressure. This increased back pressure increases the resistance to gas flow, leading to a decrease in gas flow velocity and thus reducing the pressure fluctuation amplitude within the first exhaust pipe. Since the gas can propagate in pulses, these pulses can excite vibrations in the air medium, which then propagate through the first exhaust pipe and into the surrounding air, forming sound waves. When the pressure fluctuation amplitude within the first exhaust pipe decreases, less sound energy is transmitted per unit time, resulting in reduced noise. As engine speed increases, gas pressure rises, causing the flap opening to increase. During this increase, the elastic reset component provides an elastic force to the flap, causing it to tend to reset, thus slowing down the change in flap opening amplitude, providing appropriate exhaust back pressure, and further reducing noise. Attached Figure Description

[0024] Figure 1 A schematic diagram of the structure of a means of transportation provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a power device provided in an embodiment of this application; Figure 3 for Figure 2 Top view of the power unit shown; Figure 4A A partial structural cross-sectional view of an exhaust muffler provided in an embodiment of this application; Figure 4B for Figure 4A Top view of the exhaust muffler shown; Figure 5A A partial structural cross-sectional view of a first exhaust pipe provided in an embodiment of this application; Figure 5B A partial structural cross-sectional view of an exhaust muffler provided in an embodiment of this application; Figure 5C A partial structural cross-sectional view of another exhaust muffler provided in an embodiment of this application; Figure 6AA partial structural cross-sectional view of an exhaust muffler in its initial state, provided in an embodiment of this application; Figure 6B A partial structural cross-sectional view of an exhaust muffler in a non-initial state, provided in an embodiment of this application; Figure 7 A partial structural cross-sectional view of another exhaust muffler provided in an embodiment of this application; Figure 8A This is a schematic diagram of the structure of an elastic reset member provided in an embodiment of this application; Figure 8B This is a schematic diagram of another elastic reset member provided in an embodiment of this application; Figure 9 A partial structural cross-sectional view of another exhaust muffler provided in an embodiment of this application; Figure 10 A partial structural cross-sectional view of another exhaust muffler provided in the embodiments of this application; Figure 11 This is an exploded view of an exhaust muffler provided in an embodiment of this application; Figure 12 A test graph showing the rotational speed and sound pressure level of a vehicle provided in an embodiment of this application; Figure 13 A schematic diagram of the assembly structure of a first exhaust pipe and a flow control valve provided in an embodiment of this application; Figure 14 for Figure 13 The structure shown is along A 1 A schematic diagram of the structure in the direction; Figure 15 An exploded view of a first exhaust pipe and a flow control valve provided in an embodiment of this application; Figure 16 This is a schematic diagram of the structure of a first motor provided in an embodiment of this application; Figure 17 This is a schematic diagram of the structure of a power device provided in an embodiment of this application; Figure 18 This is a schematic diagram of another power device provided in an embodiment of this application.

[0025] Figure label: 200 - Vehicle; 1 - Power unit; 2 - Second housing; 10 - Engine; 11 - Engine intake device; 12 - Engine exhaust device; 110 - Intake pipe; 111 - Intake manifold; 100 - Cylinder; 101 - Piston; 102 - Cylinder head; 103 - Cylinder block; 120 - Exhaust muffler; 121 - Third exhaust pipe; 122 - Exhaust manifold; 102a - First intake passage; 102b - First exhaust passage; 3 - First housing; 4 - Partition; 40 - Plate surface; 5 - First exhaust pipe; 6 - Second exhaust pipe; 7 - Flow control valve; 4a - Muffler hole; 5a - First intake port; 5b - First exhaust port; 6a - Second intake port; 6b - Second exhaust port; 70 - Flip plate; 71 - Elastic reset element; 50 - Exhaust channel; F - Force; N - Elastic force; 72 - First pivot; 73 - Hinge; 730 - Rotating shaft; 710 - Spring; First end - 7101; Second end - 7102; 711 - First spring; 7111 - Third end; 7112 - Fourth end; 712 - Second spring; 75 - Mounting ring; 8 - First positioning protrusion; 750 - Second positioning protrusion; 76 - Second pivot; 761 - First part; 762 - Second part; 701 - Third part; 702 - Fourth part; 763 - First hollow part; 51 - First hole; 52 - Second hole; 7121 - First hook; 7122 - Second hook; 7a - First motor; 7a1 - Output shaft; 7b - First controller; 7c - Second controller. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0027] In the following description, the terms "first," "second," etc., are used for descriptive convenience only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0028] The terms collinearity, symmetry (e.g., axial symmetry, coaxiality, or central symmetry), parallelism, perpendicularity, orthogonality, and similarity (e.g., same length, same width, etc.) mentioned in the embodiments of this application are all relative to the current technological level, and not absolute and strict mathematical definitions. Collinearity of three elements can be understood as the line connecting two elements, or its extension, intersecting with the third element, or the closest distance to the third element being approximately 2mm. A predetermined angular deviation may exist between two parallel or perpendicular components. In one embodiment, the predetermined threshold may be less than or equal to a threshold of 1mm, for example, the predetermined threshold may be 0.5mm or 0.1mm. In one embodiment, the predetermined angle may be an angle within the range of ±10°, for example, the predetermined angular deviation is ±5°.

[0029] In this application, two components are "parallel" to each other, which can mean completely parallel or approximately parallel within a certain acceptable deviation range. Furthermore, two components are "perpendicular" to each other, which can mean completely perpendicular or approximately perpendicular within a certain acceptable deviation range. The aforementioned acceptable deviation range can be determined by the limitations of the measurement system used by those skilled in the art.

[0030] In this application, unless otherwise expressly specified and limited, the term "connection" shall be interpreted broadly. For example, "connection" may be a fixed mechanical connection, a detachable mechanical connection, or an integral part; or, "connection" may be a direct connection or an indirect connection through an intermediate medium.

[0031] This application provides a means of transportation that may include an engine that produces gas during operation. For example, the engine may be a gasoline or diesel engine. Examples of the means of transportation include automobiles, motorcycles, small aircraft, and small speedboats. This application does not impose any special limitations on the specific form of the aforementioned means of transportation.

[0032] For ease of explanation, the following description uses a car as an example to illustrate the structure of this vehicle. For example, the car includes a gasoline engine.

[0033] Figure 1 This is a structural diagram of a means of transportation 200, such as... Figure 1 As shown, the vehicle 200 may include a power unit 1 and a second housing 2. At least a portion of the power unit 1 is located within the second housing 2.

[0034] The power unit 1 may include an engine 10, an engine intake device 11, and an engine exhaust device 12. The power unit 1 is used to provide the power required for the vehicle 200 to move.

[0035] The second housing 2 is mainly used to protect other structures inside the vehicle, such as the engine 10, engine intake device 11, and engine exhaust device 12. It also serves to decorate and reduce the entry of external moisture and dust into the vehicle 200.

[0036] Figure 2 yes Figure 1 A schematic diagram of the structure of the power unit 1 is shown below. Figure 2 As shown, the engine intake device 11 may include an intake pipe 110 and an intake manifold 111, the engine 10 may include a cylinder 100, a piston 101, a cylinder head 102 and a cylinder block 103, and the engine exhaust device 12 may include a third exhaust pipe 121 and an exhaust manifold 122.

[0037] The cylinder head 102 is the upper closed part of the cylinder block 103, and the cylinder head 102 is provided with a first intake passage 102a and a first exhaust passage 102b. The cylinder 100 is disposed inside the closed space enclosed by the cylinder block 103 and the cylinder head 102.

[0038] The intake pipe 110 is used to receive gas from the atmosphere. The outlet of the intake pipe 110 is connected to the inlet of the intake manifold 111. The exhaust port of the intake manifold 111 is connected to the first intake passage 102a. The first exhaust passage 102b is connected to the inlet of the exhaust manifold 122. The outlet of the exhaust manifold 122 is connected to the inlet of the third exhaust pipe 121. The third exhaust pipe 121 is used to discharge gas into the atmosphere.

[0039] Figure 3 for Figure 2 The top view of the structure shown is as follows: Figure 3 As shown, the intake manifold 111 has one intake port and four exhaust ports, each exhaust port being connected to one cylinder 100; the exhaust manifold 122 has four intake ports and one exhaust port, each exhaust port being connected to one cylinder 100. That is, the number of cylinders 100 is 4; this embodiment uses a four-cylinder engine as an example. The number of cylinders in the engine can be 3, 4, 6, 8, 10, or 12, etc., and this application is not limited to this.

[0040] The gas received in the aforementioned power unit 1 is usually air. The following detailed explanation uses air as an example, describing the process of the gas entering through the air inlet of the exhaust pipe 110 and being discharged into the atmosphere through the third exhaust pipe 121.

[0041] like Figure 2 As shown, vehicle 200 (such as Figure 1As shown, external air enters through the intake port of the engine intake manifold 110. The air entering the engine intake device 11 undergoes filtration (filtering dust, sand, pollen and other impurities in the air to prevent impurities from entering the engine and causing wear on the pistons and cylinder walls) and pressurization (increasing the engine intake pressure and density, increasing the amount of oxygen per unit volume, thereby improving combustion efficiency and power output) before entering the cylinder 100 through the exhaust port of the intake manifold 111.

[0042] Air mixes with gasoline to form a combustible mixture. The heat generated after the combustible mixture in cylinder 100 is ignited is converted into mechanical energy by piston 101, thus propelling the vehicle. The combustion products of the combustible mixture include two parts: complete combustion products, such as carbon dioxide and water vapor; and incomplete combustion products, such as carbon monoxide and unburned hydrocarbons, which are harmful substances. These products enter the engine exhaust system 12 in a pulsed manner through the intake port of exhaust manifold 122. This pulsed product causes periodic pressure fluctuations in the exhaust pipe, thereby generating sound waves.

[0043] The aforementioned combustible mixture is a homogeneous gas mixture formed by mixing combustible substances, such as gasoline and natural gas, with air in a specific ratio. It is an explosive mixture, and its explosion limits are affected by factors such as temperature and pressure.

[0044] A pulse refers to the process where exhaust pressure abruptly changes within a short period and then quickly returns to its initial state. When the engine is running and other conditions remain constant, such as engine operating conditions and engine duty cycle, exhaust pressure changes periodically. When engine operating conditions change, the period of exhaust pressure change also changes. For example, when engine speed increases, exhaust frequency increases and the exhaust pressure fluctuation period shortens; when engine speed decreases, exhaust frequency decreases and the exhaust pressure fluctuation period increases.

[0045] Rotational speed is the number of revolutions of the engine crankshaft per minute, measured in r / min or RPM. Exhaust pressure refers to the pressure of a fluid (such as gas or steam) as it exits a device or pipe. Sound waves are generated primarily because exhaust pulses during engine exhaust excite vibrations in the air medium, which then propagate through the exhaust pipe and into the surrounding air.

[0046] Since the main product of the combustion of the combustible mixture is gas, the gas entering the engine exhaust system 12 below is actually the main product of the combustion of the combustible mixture. However, for ease of explanation, the term "gas" will still be used below to refer to the main product of the combustion of the combustible mixture entering the engine exhaust system 12. The gas entering the engine exhaust system 12 is discharged into the atmosphere through the exhaust port of the engine exhaust system 12. Since the gas contains harmful gases and generates noise (irregular, non-periodic sound wave vibrations), it needs to be purified and noise-reduced before it can be safely released into the atmosphere. The purification and noise reduction processes are performed within the engine exhaust system 12.

[0047] To purify and reduce the noise of the aforementioned gases, the engine exhaust system 12 may further include, for example: Figure 2 The exhaust muffler 120 is shown. The air inlet of the third exhaust pipe 121 is connected to the air outlet of the exhaust manifold 122, and the air outlet of the third exhaust pipe 121 is connected to the air inlet of the exhaust muffler 120. The exhaust muffler 120 is used to alleviate noise problems.

[0048] Furthermore, a three-way catalytic converter (not shown in the figure) can be installed on the link formed by the third exhaust pipe 121. The three-way catalytic converter can convert harmful gases in the gas into harmless carbon dioxide, water, and nitrogen through oxidation and reduction reactions.

[0049] To illustrate the noise reduction process of the exhaust muffler 120, the specific structure of the exhaust muffler 120 is described in detail below. Figure 4A This is a partial structural cross-sectional view of an exhaust muffler 120 provided in an embodiment of this application, as shown below. Figure 4A The exhaust muffler 120 may include a first housing 3, a partition 4, a first exhaust pipe 5, and a second exhaust pipe 6. The partition 4 is located inside the first housing 3, dividing the first housing 3 into at least two cavities. The partition 4 has multiple muffler holes 4a. The first air inlet 5a of the first exhaust pipe 5 extends out of the first housing 3, and the first exhaust outlet 5b of the first exhaust pipe 5 is located inside the first housing 3 and passes through the partition 4. The second air inlet 6a of the second exhaust pipe 6 is located inside the first housing 3 and passes through the partition 4. The second exhaust outlet 6b of the second exhaust pipe 6 extends out of the first housing 3. The first exhaust outlet 5b and the second air inlet 6a are located in different cavities. The first air inlet 5a is connected to the exhaust outlet of the third exhaust pipe 121.

[0050] For ease of explanation, a coordinate system XYZ is introduced below, in which the XY plane containing the X-axis and Y-axis is parallel to the plate surface 40 of the partition 4, and the Z-axis is perpendicular to the plate surface 40.

[0051] Figure 4B for Figure 4A Please refer to the top view of the structure shown. Figure 4A and Figure 4BSince the first exhaust port 5b and the second air inlet 6a are located in different cavities via the partition 4, the gas first enters a cavity inside the first housing 3 through the first exhaust port 5b. Compared to the interface of the first exhaust pipe 5 (the cross-sectional area of ​​the first exhaust pipe along the XY plane), the interface of the cavity inside the first housing 3 (the cross-sectional area of ​​the cavity along the XY plane) is larger. This abrupt change in cross-sectional area is the abrupt change in the gas transmission channel interface. The gas then passes through the silencer hole 4a to reach another cavity. The silencer hole 4a has a smaller area, which helps to limit the cross-sectional area of ​​the airflow channel. Finally, the gas is discharged into the atmosphere through the second exhaust port 6b.

[0052] In the above process, the acoustic impedance on both sides of the abrupt change at the interface of the transmission channel will change abruptly. When the sound wave propagates through the abrupt interface, the mismatch between the two sides increases, thus some of the sound wave is reflected, canceling out a portion of the sound wave and reducing noise. Limiting the cross-sectional area of ​​the airflow channel can cause a throttling effect when high-pressure, high-speed gas passes through the orifice—the high-pressure gas is forced to slow down and split, transforming the original strong pulse high-pressure airflow into a dispersed low-pressure airflow. Because of the large pressure gradient and high turbulence intensity, the noise of high-pressure airflow is generally greater than that of low-pressure airflow; therefore, limiting the cross-sectional area of ​​the airflow channel also reduces noise. The pressure gradient is the rate of change of pressure per unit distance.

[0053] The acoustic impedance described above is a measure of the resistance encountered by sound waves when propagating in a medium. Matching refers to maximizing the transfer of sound energy by adjusting the acoustic impedance between two different media, thereby enabling the effective operation of the acoustic system. The greater the difference in acoustic impedance, the more severe the sound wave energy loss and the higher the sound wave reflectivity.

[0054] To further alleviate the noise problem, in some embodiments of this application, the exhaust muffler 120 further includes, for example... Figure 4A The flow control valve 7 shown includes a flap 70 and a resilient reset member 71. The flap 70 is connected to the first exhaust pipe 5. One end of the resilient reset member 71 is connected to the first exhaust pipe 5, and the other end of the resilient reset member 71 is connected to the flap 70. The resilient reset member 71 is used to cover at least a portion of the exhaust passage 50 of the first exhaust pipe 5 in the initial state.

[0055] The first air inlet 5a of the first exhaust pipe 5 receives gas discharged from other components connected to the exhaust muffler 120. After passing through the first exhaust pipe 5, the gas is discharged through the first exhaust port 5b into the cavity where the first exhaust port 5b is located. Since a flow control valve 7 is installed at the first exhaust port 5b of the first exhaust pipe 5, the flap 70 connected to the first exhaust pipe 5 can impede the flow of gas during its transmission within the first exhaust pipe 5, thereby increasing the exhaust back pressure. The increased exhaust back pressure increases the resistance to gas flow, leading to a decrease in gas flow velocity, which in turn reduces the pressure fluctuation amplitude of the gas inside the first exhaust pipe 5. Because the gas can propagate in the form of pulses, these gas pulses can excite vibrations in the air medium and propagate through the first exhaust pipe 5 with the surrounding air to form sound waves. When the pressure fluctuation amplitude of the gas inside the first exhaust pipe 5 decreases, the amount of sound energy transmitted per unit time decreases, and the noise level decreases. When the engine speed increases, the gas pressure increases, causing the flap 70 to open wider. As the opening of the flap 70 increases, the elastic reset member 71 can provide elastic force to the flap 70. Under the action of this elastic force, the flap 70 has a tendency to reset, thereby slowing down the change in the opening of the flap 70, providing appropriate exhaust back pressure, and thus alleviating the noise problem.

[0056] Gas pressure fluctuations are essentially a conversion of mechanical energy into sound energy. When gas pressure fluctuates, collisions between molecules intensify, and kinetic energy is transferred through the medium to form sound waves. The greater the pressure fluctuation amplitude, the more sound energy is transferred per unit time, and the stronger the noise. The smaller the pressure fluctuation amplitude, the less sound energy is transferred per unit time, and the weaker the noise. Therefore, increasing the exhaust back pressure can alleviate noise problems.

[0057] The aforementioned exhaust back pressure is the reverse pressure experienced by gas as it flows through components such as the exhaust pipe, three-way catalytic converter, and muffler during engine exhaust. Essentially, it represents the resistance of the exhaust system to gas flow. The exhaust passage 50 should be interpreted broadly. It includes not only the passage from the first intake port 5a to the first exhaust port 5b, but also a portion of the first intake port 5a facing away from the first exhaust port 5b, and a portion of the first exhaust port 5b facing away from the first intake port 5a. This is because the gas produced by the engine has the characteristic of high-speed transmission. During the exhaust process, the gas exhibits a continuous movement tendency due to its flow velocity and mass; the higher the engine speed, the stronger this continuous movement tendency.

[0058] The following is combined Figure 5A , Figure 5B and Figure 5C To further explain the principle of increasing exhaust back pressure, Figure 5A This is a partial structural cross-sectional view of the first exhaust pipe 5. Figure 5B This is a partial structural cross-sectional view of the first exhaust pipe 5, which is equipped with a flow control valve 7. Figure 5CThis is a partial structural cross-sectional view of the first exhaust pipe 5, which is equipped with a flow control valve 7, compared to... Figure 5B , Figure 5C The flow control valve shown has a larger opening.

[0059] The opening degree of a flow control valve refers to the extent to which the valve is open, reflecting the size of the flow area of ​​gas through the valve. An opening degree of 0 represents that the valve is fully closed, meaning that gas cannot flow; an opening degree of 1 represents that the valve is fully open, at which point the flow of gas is not affected by the valve.

[0060] like Figure 5A As shown, gas enters through the first inlet 5a, travels along the path of the exhaust channel 50, and exits through the first exhaust port 5b. Compared to Figure 5A The structure shown is... Figure 5B In the process, when the gas is transmitted to the first exhaust port 5b, a portion of the gas will be blocked by the flow control valve 7. As a result, the blocked gas will change direction due to the obstruction and flow in the opposite direction. This will cause gas to accumulate at the first exhaust port 5b, which will increase the gas pressure. The increase in gas pressure will create resistance to the transmission of gas, thereby increasing the exhaust back pressure.

[0061] Compared to Figure 5B The structure shown. Figure 5C In the process, when the gas is transmitted to the first exhaust port 5b, less gas is obstructed due to the flow control valve 7, and the exhaust back pressure provided is small at this time. That is, the exhaust back pressure decreases as the opening of the flow control valve increases.

[0062] The following is in conjunction with the appendix Figure 6A and Figure 6B The initial state is described in detail.

[0063] Figure 6A A partial structural cross-sectional view of an exhaust muffler 120 in its initial state, provided in an embodiment of this application, is shown below. Figure 6A In the initial state, when the engine is not working, the gas in the exhaust passage 50 is in a static state. At this time, the flap 70 is parallel to the cross section of the exhaust passage 50 along the XY plane.

[0064] Figure 6B This is a partial structural cross-sectional view of an exhaust muffler 120 in a non-initial state, as provided in an embodiment of this application. Figure 6B In the non-initial state, when the engine starts, gas flows along the interior of the exhaust passage 50. At this time, the gas inside the exhaust passage 50 exerts a force F on the flap 70, which pushes the flap 70 away from its initial position. After the flap 70 is pushed away from its initial position, the elastic reset member 71 applies an elastic force N to the flap, which causes the flap 70 to tend to return to its initial position. The force F and the elastic force N... Figure 6BThe directions of the forces F and N shown are for illustrative purposes only and do not constitute a technical constraint on actual engineering projects or relevant laws.

[0065] As the engine speed increases, the gas pressure inside the exhaust passage 50 increases, and the force F increases. Consequently, the flap 70 is pushed further away from its initial position, and thus the portion of the exhaust passage 50 covered by the flap 70 becomes smaller, and the exhaust back pressure provided by the flap 70 also decreases.

[0066] Please continue reading. Figure 6B After the flap 70 is pushed away from its initial position by the pushing force F, the flap rotates around the axis of rotation, and there is an angle γ between the flap 70 and the cross section of the exhaust channel 50 along the XY plane. Due to the limitations of the actual structure and exhaust pressure, the angle γ increases with the increase of the force F, or the angle γ increases with the increase of the force F within a certain range. When it increases to a certain extent, the angle γ remains unchanged or fluctuates within a small range.

[0067] Taking all factors into consideration Figure 6A and Figure 6B Structurally, when the shape of the flap 70 is fixed, in the initial state, the portion of the flap 70 covering the exhaust passage 50 is larger than in the non-initial state. This can also be understood as follows: as the included angle γ increases, the opening of the flap 70 decreases, and the provided exhaust back pressure also decreases. When the included angle γ remains constant, the opening of the flap 70 remains constant. Specifically, when γ=0, the opening of the flap 70 is 0, meaning the flap 70 is in its initial state (valve fully closed), and the exhaust back pressure provided by the flap 70 is at its maximum. When the included angle γ fluctuates within a small range, the opening of the flap 70 also fluctuates within a small range.

[0068] In this embodiment, the flap 70 is circular. In other embodiments, the flap 70 can be square, polygonal, or other shapes. Alternatively, in some embodiments, the shape of the flap 70 matches the inner wall shape of the first exhaust pipe 5. Or, in other embodiments, the shape of the flap 70 may not match the inner wall shape of the first exhaust pipe 5. This embodiment does not limit the scope of the application.

[0069] The above describes the noise reduction principle of flow control valves. The following section provides examples of how flow control valves can be configured. In some embodiments, such as... Figure 4A As shown, the flow control valve 7 can be located outside the first exhaust pipe 5. The flap 70 is located at one end where the first exhaust port 5b is located, and the flap 70 is hinged to the first exhaust pipe 5. Because the flap 70 is hinged to the first exhaust pipe 5, it is easier for the flap 70 to rotate and connect with the first exhaust pipe 5.

[0070] To achieve the hinged connection between the flap 70 and the first exhaust pipe 5, the flow control valve 7 may also include, for example: Figure 4AThe first rotating shaft 72 is shown. The first exhaust pipe 5 is connected to the first rotating shaft 72, and the flap 70 is rotatably connected to the first rotating shaft 72. During the gas discharge process, the gas exerts a force on the flap 70, causing the flap 70 to rotate around the first rotating shaft 72 under the influence of this force. The flap 70 obstructs the gas transmission, thereby increasing the exhaust back pressure and reducing noise.

[0071] Figure 4A In the structure shown, the first exhaust pipe 5 is connected to the first rotating shaft 72, and the flap 70 rotates around the first rotating shaft 72. Alternatively, the flap 70 can be connected to the first rotating shaft 72, and a support component can be provided on the first exhaust pipe 5, with the first rotating shaft 72 rotatably connected to this support component. Alternatively, the first exhaust pipe 5 can be rotatably connected to the first rotating shaft 72, and the flap 70 can also be rotatably connected to the first rotating shaft 72. As long as the flap 70 can rotate around the first rotating shaft 72, further details are omitted here.

[0072] The above Figure 4A The structure shown illustrates a feasible solution for hinged connection between flap 70 and first exhaust pipe 5. Further details will follow. Figure 7 Another feasible solution is introduced, in which the flap 70 is hinged to the first exhaust pipe 5.

[0073] like Figure 7 As shown, the flow control valve 7 may also include a hinge 73. One end of the hinge 73 is connected to the first exhaust pipe 5, and the other end of the hinge 73 is connected to the flap 70. In this way, the flap 70 can rotate about the rotation axis 730 of the hinge 73.

[0074] Multiple holes can be provided at both ends of the hinge 73. The connection between the hinge 73 and the first exhaust pipe 5 and the hinge 73 and the flap 70 can include riveting, screwing, etc.

[0075] The above provides a feasible solution for hinged connection between flap 70 and first exhaust pipe 5. The following describes an exemplary feasible setting of elastic reset member 71.

[0076] Figure 8A The provided diagram illustrates the structure of an elastic reset element 71, as shown below. Figure 8A As shown, the elastic reset element 71 (such as...) Figure 4A (As shown) includes a spring 710, the first end 7101 of which is connected to the first exhaust pipe 5 (as shown). Figure 4A (As shown) connected, the second end 7102 of the spring 710 is connected to the flap 70 (as shown) Figure 4A (As shown) connection.

[0077] In this way, since the flap 70 is hinged to the first exhaust pipe 5, the flap 70 can rotate relative to the first exhaust pipe 5. Furthermore, since the first end 7101 of the spring 710 is connected to the first exhaust pipe 5, and the second end 7102 of the spring 710 is connected to the flap 70, forces can be applied to both ends of the spring 710 during the rotation of the flap 70 relative to the first exhaust pipe 5. This causes the spring 710 to undergo elastic deformation matching the opening degree of the flap 70. The elastic deformation of the spring 710 generates an elastic force, which reacts on the flap 70 to control the flip angle of the flap 70 relative to the first exhaust pipe 5, i.e., the opening degree of the flap 70. This reduces the amplitude of the flap 70 opening change, allowing the flow control valve 7 to provide appropriate exhaust back pressure, thereby mitigating noise problems.

[0078] Figure 8B The provided diagram shows the structure of another type of elastic reset element 71, as follows: Figure 8B As shown, please refer to the following for comprehensive information. Figure 4A and Figure 8B The elastic reset member 71 includes a first spring 711, which can be covered by the first rotating shaft 72. The third end 7111 of the first spring 711 is connected to the first exhaust pipe 5, and the fourth end 7112 of the first spring 711 is connected to the flap 70.

[0079] Since the first exhaust pipe 5 is rotatably connected to the first rotating shaft 72, and the flap 70 is also rotatably connected to the first rotating shaft 72, the flap 70 can rotate relative to the first exhaust pipe 5 via the first rotating shaft 72. Furthermore, since the third end 7111 of the first spring 711 is connected to the first exhaust pipe 5, and the fourth end 7112 of the first spring 711 is connected to the flap 70, a force can be applied to both ends of the first spring 711 during the rotation of the flap 70 relative to the first exhaust pipe 5. This causes the first spring 711 to undergo elastic deformation matching the opening degree of the flap 70. The elastic deformation of the first spring 711 generates an elastic force, which reacts on the flap 70 to control the flip angle of the flap 70 relative to the first exhaust pipe 5, i.e., the opening degree of the flap 70. In this way, the change in the opening degree of the flap 70 is reduced, allowing the flow control valve 7 to provide appropriate exhaust back pressure, thereby alleviating noise problems.

[0080] Since engine exhaust temperatures are typically 100-300 degrees Celsius, the flap material can be made of high-temperature resistant materials, including heat-resistant steel, stainless steel, and other metal materials.

[0081] The connection between the elastic reset member 71 and the first exhaust pipe 5, and between the elastic reset member 71 and the flap, includes welding. The connection between the hinge 73 and the first exhaust pipe 5, and between the hinge 73 and the flap 70, may also include welding.

[0082] Figure 9 This is a partial structural cross-sectional view of another exhaust muffler 120 provided in this application embodiment. Figure 9 The exhaust muffler 120 shown and the above-mentioned Figure 4A The difference in the exhaust muffler 120 shown is that the flow control valve 7 further includes a mounting ring 75, at least a portion of which is nested at the first exhaust port 5b, and the mounting ring 75 is connected to the first exhaust pipe 5. A portion of the flap 70 is hinged to the mounting ring 75.

[0083] In this way, when the flap 70 is indirectly connected to the first exhaust pipe 5 through the mounting ring 75, the contact area between the mounting ring 75 and the first exhaust pipe 5 can be increased by setting the contact area between the entire flow control valve 7 and the first exhaust pipe 5, thereby improving the installation reliability of the flow control valve 7 and the first exhaust pipe 5.

[0084] Because in Figure 9 In the structure shown, with Figure 4A The difference in the structure shown is that a mounting ring 75 is added between the flap 70 and the first exhaust pipe, while other structural elements, such as the hinge between the flap 70 and the first exhaust pipe 5, and the placement of the elastic reset member 71, remain unaffected. Therefore, even with the addition of the mounting ring 75, a similar structure can be used. Figure 4A and Figure 7 The hinged connection between the flap 70 and the first exhaust pipe 5 shown can also be achieved using the following method: Figure 8A and Figure 8B The elastic reset element 71 is shown in the configuration.

[0085] Figure 10 This is a partial structural cross-sectional view of another exhaust muffler 120 provided in the embodiments of this application. Figure 10 The exhaust muffler 120 shown and the above-mentioned Figure 9 The difference in the exhaust muffler 120 shown is that the exhaust muffler 120 also includes a first positioning protrusion 8. The first positioning protrusion 8 is disposed on the first exhaust pipe 5, and correspondingly, a second positioning protrusion 750 can be disposed at a corresponding position on the mounting ring 75, and the mounting ring 75 can be nested on the first exhaust pipe 5 on which the first positioning protrusion 8 is disposed.

[0086] Mounting ring 75 can be as follows: Figure 9 or Figure 10 The completely enclosed ring shown can also be a partially enclosed ring, as long as it can be nested on the first exhaust pipe 5.

[0087] Since the exhaust temperature of an engine is typically 100-300 degrees Celsius, the material of the mounting ring 75 can include heat-resistant steel, stainless steel, or other metal materials. The connection between the mounting ring 75 and the first exhaust pipe 5 can be achieved by nesting the mounting ring 75 inside the first exhaust pipe 5 and clamping the mounting ring 75 with a clamping tool such as pliers, or by welding, riveting, or other methods.

[0088] To explain Figure 10 The positioning function of the first positioning protrusion 8 in the structure shown will be discussed below. Figure 11 An example will be provided. Figure 11 This is an exploded view of an exhaust muffler 120 provided in an embodiment of this application. A first positioning protrusion 8 is disposed on the first exhaust pipe 5 and is located in the Y direction. To make the extension direction of the first rotating shaft 72 parallel to the X direction, a second positioning protrusion 750 on the mounting ring 75 is correspondingly located in the Y direction.

[0089] The first positioning protrusion 8 and the second positioning protrusion 750 are designed to facilitate positioning during installation, for example... Figure 11 When the extension direction of the first rotating shaft 72 is parallel to the X direction, the second positioning protrusion 750 on the mounting ring 75 is positioned in the Y direction. If the extension direction of the first rotating shaft 72 is to be parallel to the Y direction, the second positioning protrusion 750 on the mounting ring 75 can be positioned in the X direction. This embodiment does not impose specific limitations on the actual structure.

[0090] In addition, in actual installation, positioning can also be achieved using other methods, such as using instruments like a level or laser alignment instrument, or by combining geometric measurement (optical, mechanical) methods. This application does not limit the scope of this method.

[0091] As mentioned above, increasing exhaust back pressure can alleviate noise problems. However, if the exhaust back pressure is increased too much, the gases produced inside the engine cannot be discharged into the atmosphere in time. This stagnation of gases within the engine's exhaust system can lead to serious consequences such as gas backflow, reduced engine efficiency, and exhaust pipe breakage. The degree of back pressure increase is related to the opening of the flow control valve. To reduce noise without affecting engine efficiency, the degree of exhaust back pressure increase should be appropriate. The following discussion will address this further. Figure 12 An example is given to illustrate the method of appropriately increasing exhaust back pressure.

[0092] Figure 12 For installation such Figure 9 The diagram shows a test chart of the vehicle's speed and sound pressure level for the exhaust muffler 120, with the engine operating at 75% load. Figure 12In the diagram, the horizontal axis represents the engine speed, and the vertical axis represents the noise sound pressure level. The solid line S1 represents the noise sound pressure level curve without a flow control valve, and the dashed line S2 represents the noise sound pressure level curve with a flow control valve installed.

[0093] The sound pressure mentioned above is a physical quantity describing the intensity of sound waves; it is the pressure change of sound waves on a gas or other medium. Sound pressure level is a unit used to describe the magnitude of sound pressure, usually expressed in decibels (dB). The formula for calculating sound pressure level is: Sound pressure level = 20 * log10 (sound pressure / reference sound pressure), where the reference sound pressure is usually taken as 20 μPa (2 × 10⁻⁵ Pa).

[0094] pass Figure 12 It can be seen that at low speeds (speed < 2500 rpm), noise improvement is significant. Compared to not having a flow control valve, the sound pressure level is reduced by 2-3 dB after installing the flow control valve. Specifically, from Figure 12 From point ① on curve S2, we can see that the noise sound pressure level at 1500 rpm is approximately 63 dB; from point ② on curve S1, we can see that the noise sound pressure level at 1500 rpm is approximately 66 dB. This means that at 1500 rpm, the noise sound pressure level with a flow control valve installed is about 3 dB lower than the noise sound pressure level without a flow control valve. This is mainly because when the engine is idling (engine speed fluctuation is small, generally ≤50 rpm), the angle γ (as shown in the image) is... Figure 6B As shown) the angle is approximately 5°~10°, and the exhaust back pressure increases by approximately 2 kPa; when the engine speed is 2200 rpm (angle γ (as shown) Figure 6B (As shown in the figure, the angle is approximately 15°~20°), and the exhaust back pressure increases by about 5 kPa. Experimental data proves that increasing the exhaust back pressure can significantly reduce noise.

[0095] At high speeds (speed > 2500 rpm), the sound pressure level is reduced to some extent (less than 1 dB) compared to when no flow control valve is used. Specifically, the sound pressure level is reduced by […]. Figure 12 As shown in the diagram, point ③ on curve S2 indicates that the noise sound pressure level at 3500 rpm is approximately 78 dB; point ④ on curve S1 indicates that the noise sound pressure level at 3500 rpm is approximately 79 dB. This means that at 3500 rpm, the noise sound pressure level with a flow control valve installed is about 1 dB lower than that without. This is mainly because as engine speed increases, the gas flow velocity increases, and the gas pressure increases, thus increasing the angle γ (e.g., ...). Figure 6B (As shown) increase, flip plate 70 (as shown) Figure 6B As shown) for exhaust passage 50 (e.g. Figure 6BThe insufficient coverage of the exhaust pipe (as shown) results in a lower exhaust back pressure and a certain degree of noise reduction. This also reduces the resistance to high-velocity gas, preventing gas buildup in the first exhaust pipe 5 (as shown). Figure 6B (As shown) to avoid affecting engine efficiency.

[0096] Angle γ (e.g.) Figure 6B The process of change (as shown) includes the application of force F (such as...) Figure 6B (as shown) and elastic force N (as shown) Figure 6B The process involves the combined action of the springs (as shown). When the elastic return element is a spring, the following example illustrates the spring configuration. The first spring 711 (as shown) Figure 8B The elastic force N provided by (as shown) Figure 6B As shown, the first spring 711 (as indicated) is affected by the torsional stiffness coefficient K, thus... Figure 8B The torsional stiffness coefficient K (as shown) affects the exhaust back pressure.

[0097] The following are the K values ​​used in this test:

[0098] Where P is the maximum back pressure of the engine, D is the inner diameter of the exhaust pipe, and G is the weight of the flap.

[0099] According to experimental tests, when the included angle γ (such as...) Figure 6B When the angle (as shown) is greater than 45°, the exhaust back pressure provided by the flow control valve is almost zero. Furthermore, within the gas pressure range that the flow control valve's structure can withstand, the limiting range of the included angle γ is 46°~53°. Beyond this range, the exhaust back pressure provided by the flow control valve is small, and there is essentially no noise reduction effect.

[0100] The spring settings are similar to those of the springs described above, and will not be repeated here.

[0101] The torsional stiffness coefficient K mentioned above is a core parameter for measuring the ability of a material or structure to resist torsional deformation, representing the torsional angle generated under unit torque. The maximum back pressure of an engine is the highest pressure threshold that the exhaust system can withstand under specific operating conditions (such as a load of 75%). Determining the maximum back pressure of an engine requires combining measured data with design parameters. Its core logic is to find the critical value at which exhaust resistance significantly affects power and fuel economy through correlation analysis between exhaust system pressure and engine performance.

[0102] The above section introduced a flow control valve with a flap located outside the first exhaust pipe. Next, we will introduce a flow control valve with a flap located inside the first exhaust pipe.

[0103] Figure 13This is a schematic diagram of an assembly structure of a first exhaust pipe 5 and a flow control valve 7 according to an embodiment of this application. The flow control valve 7 includes a flap 70 and an elastic reset member 71. The flap 70 is connected to the first exhaust pipe 5. One end of the elastic reset member 71 is connected to the first exhaust pipe 5, and the other end of the elastic reset member 71 is connected to the flap 70. The elastic reset member 71 is used to cover at least a portion of the exhaust passage 50 of the first exhaust pipe 5 in the initial state. The flap 70 is located inside the first exhaust pipe 5 and is hinged to the first exhaust pipe 5.

[0104] In this way, the flow control valve 7 can increase the exhaust back pressure, thereby alleviating the noise problem, and does not occupy the first housing 3 (e.g. Figure 4A The space where the cavity is located.

[0105] Please continue reading. Figure 13 The flow control valve 7 also includes a second rotating shaft 76, which is arranged intersecting the extension direction of the first exhaust pipe 5. The second rotating shaft 76 includes a first part 761 and a second part 762. The first part 761 is located inside the first exhaust pipe 5 and is connected to the flap 70. The second part 762 extends out of the first exhaust pipe 5. The elastic reset member 71 includes a second spring 712, and the second part 762 passes through the second spring 712. One end of the second spring 712 is connected to the first exhaust pipe 5, and the other end of the second spring 712 is connected to the end of the second part 762 opposite to the first part 761.

[0106] Since the second part 762 of the second rotating shaft 76 extends out of the first exhaust pipe 5, and the second spring 712 passes through the second rotating shaft 76, one end of the second spring 712 is connected to the first exhaust pipe 5, and the other end of the second spring 712 is connected to the end of the second part 762 opposite to the first part 761. Therefore, during the rotation of the flap 70 relative to the first exhaust pipe 5, a force can be applied to both ends of the second spring 712, causing the second spring 712 to undergo elastic deformation matching the opening degree of the flap 70. After the second spring 712 undergoes elastic deformation, it generates elastic force, which can react on the flap 70 to control the flip angle of the flap 70 relative to the first exhaust pipe 5, i.e., the opening degree of the flap 70. In this way, the change in the opening degree of the flap 70 is slowed down, allowing the flow control valve 7 to provide a suitable exhaust back pressure. As a result, the pressure fluctuation amplitude of the gas inside the first exhaust pipe is reduced, and less sound energy is transmitted per unit time, thereby alleviating the noise problem.

[0107] Figure 14 for Figure 13 The structural diagram shown is along the A1 direction. Please refer to it for further details. Figure 13 and Figure 14The flap 70 includes a third part 701 and a fourth part 702. A second rotating shaft 76 is located between the third part 701 and the fourth part 702, and the third part 701 and the fourth part 702 can be symmetrically arranged about the second rotating shaft 76. Compared to an asymmetrical arrangement of the third part 701 and the fourth part 702 about the second rotating shaft 76, when the third part 702 and the fourth part 702 are symmetrically arranged, the second rotating shaft 76 passes through the axis of the first exhaust pipe 5, which makes actual processing and installation easier.

[0108] Figure 15 The following is shown Figure 13 An exploded view of the structure shown is as follows: Figure 15 The second rotating shaft 76 includes a first hollow portion 763, and the first exhaust pipe 5 includes a first hole portion 51 and a second hole portion 52. The second rotating shaft 76 passes through the first hole portion 51 into the first exhaust pipe 5 and exits through the second hole portion 51. In actual installation, the first portion 761 can be inserted into the first hole portion 51 and the second hole portion 52, and the flap 70 can be inserted into the first hollow portion 763. To connect the flap 70 and the first hollow portion 763, holes can be provided at the flap 70 and the first hollow portion 763, so that the flap 70 and the second rotating shaft 76 can be connected by riveting, screwing, or other methods.

[0109] Furthermore, the second part 762 can be larger than the first part 761, and the second part 762 cannot be inserted into the first hole 51 or the second hole 52. In this way, during actual installation, after the first part 761 is inserted into the first hole 51 and the second hole 52, the second part 762 cannot be inserted into either the first hole 51 or the second hole 52, which facilitates positioning and installation.

[0110] Please continue reading. Figure 15 The second spring 712 includes a first hook portion 7121 and a second hook portion 7122. The first hook portion 7121 is located at one end of the second spring 712, and the other end of the second spring 712 is provided with the second hook portion 7122. The first hook portion 7121 can hook onto the first exhaust pipe 5 (e.g., Figure 13 As shown), the second hook 7122 can hook onto the second part 762 (as shown). Figure 13 As shown above. In this way, when the opening of the flap changes, the second spring 712 can provide an elastic force, under the action of this elastic force, the flap has a tendency to return to the initial state.

[0111] Figure 13In the structure shown, the second rotating shaft 76 will rub against the first exhaust pipe 5 during rotation, which may cause structural wear over time. To solve this problem, bushings can be provided between the first hole 51 and the second rotating shaft 76, and between the second hole 52 and the second rotating shaft 76. In addition, to reduce wear between the second spring 712 and the second rotating shaft 76, a bushing can be provided between the second spring 712 and the second rotating shaft 76.

[0112] Since engine exhaust temperatures are typically 100-300 degrees Celsius, the bushing material can include polyetheretherketone (PEEK), fiberglass, etc. The flap 70 and the second rotating shaft 76 are made of metal materials such as heat-resistant steel and stainless steel.

[0113] The connection between the flap 70 and the second rotating shaft 76 may include welding, and the connection between the second spring 712 and the first exhaust pipe 5 and the second spring 712 and the second part 762 may also include welding.

[0114] Furthermore, in some embodiments of this application, the flow control valve 7 may include multiple second rotating shafts 76, multiple flaps 70, and multiple elastic reset members 71, all disposed within the first exhaust pipe 5. In this case, to enable the flow control valve 7 to increase the appropriate back pressure, the K values ​​of the multiple elastic reset members 71 need to be designed separately. In other embodiments of this application, embodiments of the flaps 70 outside the first exhaust pipe 5 and embodiments of the flaps 70 inside the first exhaust pipe 5 can be simultaneously connected to the first exhaust pipe 5, as long as they do not interfere with each other.

[0115] In some of the above embodiments, the flap opening passively changes as the exhaust pressure increases. To dynamically change the flap opening, in some embodiments, the flow control valve 7 may further include, for example... Figure 16 The first motor 7a is shown. The output shaft 7a1 of the first motor 7a is connected to the second rotating shaft 76. The first motor is used to drive the rotation of the second rotating shaft 76, thereby controlling the opening degree of the flap 70. In this way, the first motor 7a can automatically control the opening degree of the flow control valve 7, thereby adjusting the exhaust back pressure and alleviating the noise problem.

[0116] In other embodiments, the output shaft 7a1 of the first motor 7a is connected to the first rotating shaft 72 (e.g., Figure 4A (As shown) connection, the first motor 7a is used to drive the first rotating shaft 72 (as shown) Figure 4A The rotation of the flap 70 (as shown) controls the opening degree of the flap 70.

[0117] Figure 17 This is a schematic diagram of the structure of a power device 1 provided in an embodiment of this application, as shown below. Figure 17As shown, the power unit 1 includes an exhaust muffler 120. The flow control valve 7 of the exhaust muffler 120 also includes a first motor 7a. The output shaft 7a1 of the first motor 7a is connected to the second rotating shaft 76 of the flow control valve 7, and the first motor 7a drives the second rotating shaft 76 to rotate. The power unit 1 also includes a first controller 7b, which is electrically connected to the first motor 7a and the engine 10. The first controller 7b is used to acquire the speed of the engine 10 and control the rotation of the output shaft 7a1 according to the speed, thereby controlling the opening of the flap 70. In this way, the first motor 7a can automatically control the opening of the flow control valve 7, thereby adjusting the exhaust back pressure and alleviating the noise problem.

[0118] Figure 18 This is a schematic diagram of another power unit 1 provided in an embodiment of this application, as shown below. Figure 18 As shown, the power unit 1 also includes an intake manifold 111, a pressure sensor 112, and a second controller 7c. The exhaust port of the intake manifold 111 is connected to the first intake passage 102a on the cylinder head 102. The pressure sensor 112 is mounted on the intake manifold 111 and is used to detect gas pressure. The flow control valve 7 of the exhaust muffler 120 also includes a first motor 7a. The output shaft 7a1 of the first motor 7a is connected to the second rotating shaft 76 of the flow control valve 7, and the first motor 7a is used to drive the second rotating shaft 76 to rotate. The second controller 7c is electrically connected to the first motor 7a and the pressure sensor 112. The second controller 7c is used to acquire the detection data of the pressure sensor 112 and control the rotation of the output shaft 7a1 according to the detection data, thereby controlling the opening degree of the flap 70. In this way, the first motor 7a can automatically control the opening degree of the flow control valve 7, thereby adjusting the exhaust back pressure and mitigating noise problems.

[0119] In summary, the first motor can automatically adjust the opening of the flap based on the engine speed and the gas pressure entering the engine. In addition, it can also automatically adjust the flap opening by combining engine speed and gas pressure data, thereby alleviating noise problems.

[0120] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An exhaust silencing device, characterized by The exhaust silencing device comprises: a first shell; a partition plate, which is located in the first shell and divides the first shell into at least two cavities, and a plurality of sound holes are formed in the partition plate; a first exhaust pipe; a first air inlet of the first exhaust pipe extends out of the first shell, and a first air outlet of the first exhaust pipe is located in the first shell and penetrates the partition plate; a second exhaust pipe; a second air inlet of the second exhaust pipe is located in the first shell and penetrates the partition plate; a second air outlet of the second exhaust pipe extends out of the first shell; the first air inlet and the second air inlet are located in different cavities, respectively; and a flow control valve, which comprises a flap and an elastic return member; the flap is connected with the first exhaust pipe; one end of the elastic return member is connected with the first exhaust pipe, and the other end of the elastic return member is connected with the flap; 2. The exhaust silencing device of claim 1, wherein the elastic return member is used to cover at least part of the exhaust passage of the first exhaust pipe with the flap in an initial state. The flow control valve is located outside the first exhaust pipe; the flap is located at one end of the first air outlet, and the flap is hinged with the first exhaust pipe.

3. The exhaust silencing device according to claim 2, wherein the flow control valve further comprises a mounting ring, at least a part of the mounting ring is nested at the first air outlet, and the mounting ring is connected with the first exhaust pipe; a part of the flap is hinged with the mounting ring.

4. The exhaust silencing device according to claim 2 or 3, wherein the flow control valve further comprises a first rotating shaft; the first exhaust pipe is rotationally connected with the first rotating shaft, and the flap is rotationally connected with the first rotating shaft; the elastic return member comprises a first spring; the first rotating shaft is arranged in the first spring; a third end of the first spring is connected with the first exhaust pipe, and a fourth end of the first spring is connected with the flap.

5. The exhaust silencing device according to claim 2 or 3, wherein 6. The exhaust silencing device of claim 1, wherein the elastic return member comprises a spring piece; a first end of the spring piece is connected with the first exhaust pipe, and a second end of the spring piece is connected with the flap. the flap is located in the first exhaust pipe, and the flap is hinged with the first exhaust pipe.

7. The exhaust silencing device according to claim 6, wherein the flow control valve further comprises a second rotating shaft, which is arranged transversely to the extension direction of the first exhaust pipe; the second rotating shaft comprises a first part and a second part; the first part is located in the first exhaust pipe and connected with the flap; the second part extends out of the first exhaust pipe; the elastic return member comprises a second spring; the second part is arranged in the second spring; one end of the second spring is connected with the first exhaust pipe, and the other end of the second spring is connected with the second part away from the first part.

8. The exhaust silencing device according to claim 7, wherein The flap comprises a third portion and a fourth portion; the second rotating shaft is located between the third portion and the fourth portion; the third portion and the fourth portion are symmetrically arranged about the second rotating shaft.

9. The exhaust silencing device according to any one of claims 7-8, characterized in that, The flow control valve further comprises: A first motor located in the first housing, an output shaft of the first motor being connected with the second rotating shaft, the first motor being used to drive the second rotating shaft to rotate, thereby controlling the opening degree of the flap.

10. The exhaust silencing device according to any one of claims 1 to 9, characterized in that The material of the flap comprises heat-resistant steel, stainless steel and other metal materials.

11. A power plant characterized by Comprise: The exhaust silencer according to any one of claims 1-10; And, An engine, the engine comprising a cylinder head; a first exhaust passage on the cylinder head being connected with the first inlet of the first exhaust pipe in the exhaust silencer.

12. The power device according to claim 11, wherein, The flow control valve in the exhaust silencer comprises a first motor, an output shaft of the first motor being connected with a second rotating shaft of the flow control valve, the first motor being used to drive the second rotating shaft to rotate; The power device further comprises a first controller; the first controller being electrically connected with the first motor and the engine; the first controller being used to acquire the rotating speed of the engine, and control the rotation of the output shaft of the first motor according to the rotating speed, thereby controlling the opening degree of the flap.

13. The power plant of claim 11, wherein, The power device further comprises: An intake manifold, an exhaust port of the intake manifold being connected with the first inlet on the cylinder head; and A pressure sensor arranged on the intake manifold, the pressure sensor being used to detect the gas pressure; The flow control valve in the exhaust silencer comprises a first motor, an output shaft of the first motor being connected with a second rotating shaft of the flow control valve, the first motor being used to drive the second rotating shaft to rotate; The power device further comprises a second controller; the second controller being electrically connected with the first motor and the pressure sensor; the second controller being used to acquire the detection data of the pressure sensor, and control the rotation of the output shaft of the first motor according to the detection data, thereby controlling the opening degree of the flap.

14. A vehicle, characterized by Comprise: The power device according to any one of claims 11-13; A second housing, at least part of the power device being located in the second housing.

15. A flow control valve characterized by, For being connected with the first exhaust pipe, the flow control valve comprises: A flap, the flap being hingedly connected with the first exhaust pipe; A resilient reset member, one end of the resilient reset member being connected with the first exhaust pipe, the other end of the resilient reset member being connected with the flap; the resilient reset member being used to cover at least part of the exhaust passage of the first exhaust pipe with the flap in an initial state.

Images