Mixer and engine

Abstract

The present invention discloses a mixer and an engine. The mixer includes a mixer housing and a gas connector; the mixer housing has an air inlet, a first inner cavity, a second inner cavity and a mixed gas outlet that are sequentially connected along a first direction, and the first inner cavity and the second inner cavity are connected through a reducing mechanism; the gas connector is connected to the first inner cavity; the reducing mechanism includes a fixed disk, a baffle and a drive assembly; the fixed disk is relatively fixed to the mixer housing, and the axial direction of the fixed disk is parallel to the first direction, and the fixed disk has a through hole that connects the first inner cavity and the second inner cavity; the baffle is rotatably mounted on the fixed disk through a rotating shaft, and is used to cover or expose the through hole; the drive assembly is transmission-connected to the baffle, and is used to drive the baffle to rotate around the rotating shaft to adjust the shielding area of ​​the baffle on the through hole. When the air intake flow rate of the mixer is large, the flow area becomes larger, reducing the air intake resistance; when the air intake flow rate is small, the flow area becomes smaller, forcibly establishing a pressure difference, making the measurement accurate, improving the control accuracy, and adapting to different working conditions.

Description

Technical Field

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

[0002] China VI natural gas engines utilize an equivalence ratio and single-point premixing technology. Torque output depends on the intake air volume. Simply increasing the gas volume does not improve engine performance and may, on the contrary, lead to deteriorating combustion and excessive emissions. Since the gas volume is based on the amount of air injected, accurate air volume measurement is crucial. A Venturi structure and pressure sensor are used in the mixer to measure air volume, achieving high accuracy when intake air flow is high. However, at low intake air flow rates, a pressure differential cannot be established, resulting in reduced measurement accuracy. Summary of the Invention

[0003] The invention discloses a mixer and an engine, which are used to change the flow area to adapt to the change of the working condition of the natural gas engine.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] In a first aspect, the present invention provides a mixer, comprising: a mixer housing and a gas connector;

[0006] The mixer housing has an air inlet, a first inner cavity, a second inner cavity and a mixed gas outlet which are sequentially connected along a first direction, the first inner cavity and the second inner cavity are connected via a diameter reducing mechanism; the gas connector is connected to the first inner cavity;

[0007] The diameter-changing mechanism includes a fixed plate, a baffle and a drive assembly; the fixed plate is relatively fixed to the mixer housing, and the axial direction of the fixed plate is parallel to the first direction, and the fixed plate has a through hole connecting the first inner cavity and the second inner cavity; the baffle is rotatably mounted on the fixed plate via a rotating shaft, and is used to shield or expose the through hole; the drive assembly is transmission-connected to the baffle, and is used to drive the baffle to rotate around the rotating shaft to adjust the shielding area of ​​the through hole by the baffle.

[0008] In the above-mentioned mixer, air enters the first inner cavity from the air inlet, and gas enters the first inner cavity from the gas connector. After the gas and air are mixed, they pass through the reducing mechanism and enter the second inner cavity. Specifically, the fixed plate in the reducing mechanism is relatively fixed to the mixer housing, such as the fixed plate is installed in the first inner cavity or the second inner cavity, and the fixed plate has a through hole connecting the first inner cavity and the second inner cavity. The baffle is installed on the fixed plate by rotating the rotating shaft. The driving component can drive the baffle to rotate around the rotating shaft, so that the baffle covers or exposes the through hole during the relative rotation of the fixed plate, and then adjusts the size of the shielding area of ​​the through hole by the baffle, so that the flow area of ​​the through hole changes to adapt to different working conditions. The mixer provided by the present invention increases the flow area when the intake flow rate is large, reducing the intake resistance; when the intake flow rate is small, the flow area becomes smaller, forcibly establishing a pressure difference, making the measurement accurate, and improving the control accuracy.

[0009] In some embodiments, there are multiple baffles, which are arranged in a ring around the axis of the fixed disk and spliced ​​to form a variable diameter structure, and the edges of the multiple baffles are spliced ​​in the middle of the variable diameter structure to form a through hole connected to the through hole;

[0010] The driving assembly is used to drive at least one baffle to rotate around its corresponding rotation axis along a second direction to adjust the size of the through hole, wherein the second direction is a clockwise direction or a counterclockwise direction.

[0011] In some embodiments, the plurality of baffles are evenly distributed around the axis of the fixed disk; and / or,

[0012] The plurality of baffles are arranged in sequence along the axis of the fixed disk.

[0013] In some embodiments, the baffle has an arc-shaped splicing portion on the side close to the fixed disk axis, and the edge of the arc-shaped splicing portion facing the fixed disk is arc-shaped; in the variable diameter structure formed by splicing multiple baffles, the outer contour of the through hole is a closed figure formed by connecting multiple arc segments end to end.

[0014] In some embodiments, the drive assembly includes a driving part and a transmission gear pair, the transmission gear pair includes a driving gear and a driven gear transmission-connected to the driving gear, the driving gear is transmission-connected to the driving part, and the driven gear is transmission-connected to the baffle.

[0015] In some embodiments, the blocking piece is located between the fixed plate and the driven gear;

[0016] The driven gear is provided with a toggle shaft corresponding to each of the blocking pieces on a side thereof facing the blocking piece, and each of the blocking pieces is provided with a track groove slidingly matched with the toggle shaft on a side thereof facing the driven gear; or

[0017] A shifting shaft is provided on the side of each blocking piece facing the driven gear, and a track groove is provided on the surface of the driven gear facing the blocking piece, which is respectively slidably matched with each shifting shaft.

[0018] In some embodiments, the track groove is arc-shaped, and the opening of the arc faces the axis of the fixed disk; or,

[0019] When the baffle is provided with a track groove, the track groove is a through groove, and the fixed plate is provided with an annular groove on a side facing the baffle, and the shifting shaft passes through the track groove and is slidably engaged with the annular groove.

[0020] In some embodiments, a first mixer core and a second mixer core arranged along a first direction are disposed inside the mixer housing, the first mixer core is inserted into the second mixer core to form the first inner cavity, and the second mixer core cooperates with the first mixer core to form the second inner cavity;

[0021] The driven gear is arranged inside the second mixer core, and the driving gear is embedded in the mixer housing and penetrates the outer wall of the second mixer core to engage with the driven gear.

[0022] In some embodiments, the driving part includes an electric motor, a hydraulic motor, or a pneumatic motor.

[0023] In a second aspect, the present invention further provides an engine comprising the mixer as described in any one of the first aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A three-dimensional stereogram of a mixer provided by an embodiment of the present invention;

[0025] Figure 2 A front view of a mixer provided by an embodiment of the present invention;

[0026] Figure 3 A left side view of a mixer provided by an embodiment of the present invention;

[0027] Figure 4 A rear view of a mixer provided by an embodiment of the present invention;

[0028] Figure 5 A top view of a mixer provided by an embodiment of the present invention;

[0029] Figure 6 for Figure 2 Middle AA section view;

[0030] Figure 7 for Figure 5 Middle BB cross-section;

[0031] Figure 8 for Figure 7 Enlarged view of the middle reducer;

[0032] Figure 9 Assemble three-dimensional diagram of the fixed plate, baffle and driven gear in the reducing mechanism;

[0033] Figure 10 The main view of the assembly of the fixed plate, baffle and driven gear in the reducing mechanism;

[0034] Figure 11 This is a top view of the fixed plate, baffle and driven gear assembly in the reducing mechanism;

[0035] Figure 12 Explosion of the assembly structure of the fixed plate, baffle and driven gear in the diameter reducing mechanism Figure 1 ;

[0036] Figure 13 Explosion of the assembly structure of the fixed plate, baffle and driven gear in the diameter reducing mechanism Figure 2 ;

[0037] Figure 14 Schematic diagram of the distribution of baffles on the fixed plate in the diameter reducing mechanism Figure 1 ;

[0038] Figure 15 Schematic diagram of the distribution of baffles on the fixed plate in the diameter reducing mechanism Figure 2 ;

[0039] Figure 16 It is a three-dimensional stereogram of the fixed plate in the diameter reducing mechanism;

[0040] Figure 17 This is the main view of the fixed plate in the reducing mechanism;

[0041] Figure 18 for Figure 17 Middle CC section view;

[0042] Figure 19 This is the main view of the driven gear in the reducing mechanism;

[0043] Figure 20 It is the left view of the driven gear in the reducing mechanism;

[0044] Figure 21 A schematic diagram of the structure of the baffle in the diameter-changing mechanism in the first limit position;

[0045] Figure 22 It is a structural schematic diagram of the baffle in the diameter-changing mechanism being in the second extreme position.

[0046] Icons: 1-Mixer housing; 11-Air inlet; 12-First inner cavity; 13-Second inner cavity; 14-Mixed gas outlet; 15-Exhaust gas recirculation inlet; 2-Gas connector; 21-Gas nozzle; 3-Exhaust gas recirculation valve; 4-Measuring element; 41-Exhaust gas recirculation temperature sensor; 42-Exhaust gas recirculation pressure sensor; 43-Temperature and pressure sensor; 5-Variator mechanism; 6-First mixer core; 7-Second mixer core; 51-Fixed plate; 52-Baffle; 53-Electric motor; 54-Driving gear; 55-Driven gear; 511-Rotating shaft; 512-Annular groove; 521-Axis hole; 522-Track groove; 551-Switch shaft. DETAILED DESCRIPTION

[0047] First, let's introduce the application scenario of this application: the mixer is a device in a natural gas engine that mixes fuel gas, air, and exhaust gas. The equivalence ratio, or excess air coefficient, is equal to 1. Single-point premixing technology means that air and fuel gas are mixed outside the cylinder before entering the cylinder. Natural gas engines use an equivalence ratio and single-point premixing technology. The amount of fuel gas is injected based on the amount of air, so accurate measurement of the amount of air is particularly important. Traditional technology uses a Venturi structure and a pressure sensor in the mixer to measure the amount of air. The measurement accuracy is high when the intake flow rate is large. However, when the intake flow rate is small, the pressure difference cannot be established, and the measurement accuracy decreases.

[0048] Based on the above application scenarios, the embodiments of the present application provide a mixer and an engine, the flow area of ​​which can change with the working conditions. When the intake flow rate is large, the flow area is increased to reduce the intake resistance; when the intake flow rate is small, the flow area is reduced to forcibly establish a pressure difference, make the measurement accurate, and improve the control precision.

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0050] First, as Figures 1 to 7As shown, an embodiment of the present invention provides a mixer, comprising: a mixer housing 1 and a gas connector 2; the mixer housing 1 has an air inlet 11, a first inner cavity 12, a second inner cavity 13 and a mixed gas outlet 14 connected in sequence along a first direction, and the first inner cavity 12 and the second inner cavity 13 are connected via a reducing mechanism 5; the gas connector 2 is connected to the first inner cavity 12; the reducing mechanism 5 includes a fixed plate 51, a baffle 52 and a drive assembly; the fixed plate 51 is relatively fixed to the mixer housing 1, and the axial direction of the fixed plate 51 is parallel to the first direction, and the fixed plate 51 has a through hole connecting the first inner cavity 12 and the second inner cavity 13; the baffle 52 is rotatably mounted on the fixed plate 51 via a rotating shaft 511, and is used to shield or expose the through hole; the drive assembly is transmission-connected to the baffle 52, and is used to drive the baffle 52 to rotate around the rotating shaft 511 to adjust the shielding area of ​​the through hole by the baffle 52.

[0051] It should be noted that, referring to Figure 1 The mixer housing 1 also includes an exhaust gas recirculation inlet 15, which is equipped with an exhaust gas recirculation valve 3 for controlling the amount of exhaust gas. Air enters the first inner chamber 12 through the air inlet 11 of the mixer housing 1. Gas enters the gas nozzle 21 through the gas connector 2, and then passes through the nozzle holes distributed on the gas nozzle 21, entering the first inner chamber 12 and mixing with the air. Exhaust gas enters the second inner chamber 13 through the exhaust gas recirculation inlet 15 of the mixer housing 1. There, it mixes with the gas and air mixture that entered the second inner chamber 13 from the reducing mechanism 5. Finally, the mixture of air, gas, and exhaust gas flows out of the mixer through the mixed gas outlet 14.

[0052] It should also be noted that the mixer also includes a measuring element 4, such as Figure 1 As shown, measuring element 4 includes an exhaust gas recirculation temperature sensor 41, an exhaust gas recirculation pressure sensor 42, and a temperature and pressure sensor 43. The exhaust gas recirculation temperature sensor 41 and the exhaust gas recirculation pressure sensor 42 can be used to measure the temperature and pressure of the exhaust gas, thereby calculating the exhaust gas flow rate. The temperature and pressure sensor 43 can be used to measure the temperature and pressure of the intake air, i.e., the mixture of air and fuel gas.

[0053] The flow area of ​​the mixer can be understood as the exposed area of ​​the through hole connecting the first inner cavity 12 and the second inner cavity 13 , that is, the flow area of ​​the mixer is the flow area of ​​the diameter-reducing mechanism 5 between the first inner cavity 12 and the second inner cavity 13 .

[0054] In the above-mentioned mixer, air enters the first inner cavity 12 from the air inlet 11, and gas enters the first inner cavity 12 from the gas connector 2. After the gas and air are mixed, they pass through the reducing mechanism 5 and enter the second inner cavity 13. Exhaust gas enters the second inner cavity 13 from the exhaust gas recirculation inlet 15 on the mixer housing 1, and the three are mixed in the second inner cavity 13. Specifically, the fixed disk 51 in the reducing mechanism 5 is relatively fixed to the mixer housing 1. For example, the fixed disk 51 is installed in the first inner cavity 12 or the second inner cavity 13, and the fixed disk 51 has a through hole connecting the first inner cavity 12 and the second inner cavity 13. The baffle 52 is rotatably installed on the fixed disk 51 via a rotating shaft 511. The driving assembly can drive the baffle 52 to rotate around the rotating shaft 511, so that the baffle 52 covers or exposes the through hole during the rotation relative to the fixed disk 51, thereby adjusting the size of the covering area of ​​the through hole by the baffle 52, thereby changing the flow area of ​​the through hole to adapt to different working conditions. The mixer provided by the embodiment of the present invention increases the flow area and reduces the intake resistance when the intake flow is large; and decreases the flow area and forcibly establishes a pressure difference when the intake flow is small, thereby making the measurement accurate and improving the control precision.

[0055] Reference Figure 8 The mixture of gas and air can enter the second inner cavity 13 from the first inner cavity 12 through the through hole of the fixed disk 51. A baffle 52 is rotatably installed on the fixed disk 51. The driving component drives the baffle 52 to rotate around the rotating shaft 511, so that the baffle 52 covers or exposes the through hole during the rotation process. As the baffle 52 rotates, the range of the through hole blocked becomes larger or smaller, thereby changing the flow area of ​​the reducing mechanism 5 to adapt to the needs of different working conditions.

[0056] In some embodiments, there is only one baffle 52, and the drive assembly drives the baffle 52 to rotate clockwise or counterclockwise around the rotation axis 511. It is understandable that the baffle 52 can rotate within a certain range, thereby shielding or exposing the through-hole on the fixed disk 51. It should be noted that within the rotation range of the baffle 52, the baffle 52 will not completely block the through-hole, that is, the first inner cavity 12 and the second inner cavity 13 are always connected; within the rotation range of the baffle 52, the baffle 52 can completely expose the through-hole, and the range of the through-hole blocked will increase or decrease, thereby changing the flow area of ​​the diameter-changing mechanism 5 to meet the needs of different working conditions.

[0057] In some embodiments, there are multiple baffles 52, and the multiple baffles 52 are arranged in a ring around the axis of the fixed disk 51 and spliced ​​to form a variable diameter structure. The edges of the multiple baffles 52 are spliced ​​in the middle of the variable diameter structure to form a through hole connected to the through hole; the driving component is used to drive at least one baffle 52 to rotate around its corresponding rotation axis 511 along the second direction to adjust the size of the through hole, wherein the second direction is clockwise or counterclockwise.

[0058] In one possible implementation, there are multiple baffles 52, that is, two or more baffles 52, arranged in a ring around the axis of the fixed disk 51. Accordingly, the fixed disk 51 has multiple rotation axes 511, which are arranged in a ring around the axis of the fixed disk 51. All baffles 52 are spliced ​​together to form a variable diameter structure. The edges of all baffles 52 facing the axis of the fixed disk 51 are spliced ​​in the middle of the variable diameter structure to form a through hole that communicates with the through hole. As the baffle 52 rotates around its own rotation axis 511, the size of the through hole increases or decreases.

[0059] It can be understood that the maximum flow area of ​​the variable diameter mechanism 5 is the area of ​​the through-holes on the fixed disk 51, and the minimum flow area of ​​the variable diameter mechanism 5 is determined by the area of ​​the through-holes in the variable diameter structure formed by the splicing of all the baffles 52. When the baffles 52 are in the first extreme position, the size of the through-holes is equal to the size of the through-holes, that is, the flow area of ​​the variable diameter mechanism 5 is maximum and equal to the area of ​​the through-holes on the fixed disk 51. When the baffles 52 are in the second extreme position, the size of the through-holes is smaller than the size of the through-holes, that is, the flow area of ​​the variable diameter mechanism 5 is minimum and equal to the area of ​​the through-holes in the variable diameter structure. Therefore, the through-hole area is less than or equal to the through-hole area, and the minimum value of the through-hole area is not zero.

[0060] For example, when the baffle 52 switches from the first extreme position to the second extreme position, the drive assembly drives the baffle 52 to rotate counterclockwise around the rotation axis 511 by a certain angle; when the baffle 52 switches from the second extreme position to the first extreme position, the drive assembly drives the baffle 52 to rotate clockwise around the rotation axis 511 by a certain angle. The rotation direction and angle of the baffle 52 around the rotation axis 511 can be precisely controlled by the drive assembly, and the rotation direction and angle values ​​can be determined based on the specific operating conditions of the engine.

[0061] In some embodiments, the plurality of baffles 52 are evenly distributed around the axis of the fixed disk 51 , so that the area of ​​the via hole can be easily calculated, thereby facilitating precise control of the driving assembly.

[0062] In some embodiments, to prevent interference between baffles 52 during rotation, multiple baffles 52 are arranged sequentially along the axis of the fixed disk 51. The orthographic projections of the baffles 52 on the plane of the fixed disk 51 overlap during rotation, so the multiple baffles 52 are arranged along the axis of the fixed disk 51. It should be noted that to prevent gas leakage between adjacent layers of baffles 52, the gap between the two layers of baffles 52 is as small as possible, for example, there is a contact surface between the two layers of baffles 52. To prevent friction between the two layers of baffles 52 during rotation, the surfaces of the two layers of baffles 52 can be smoothed.

[0063] In one possible implementation, all the baffles 52 are arranged in sequence along the axis of the fixed disk 51 , that is, each baffle 52 is located in one layer.

[0064] In another possible implementation, all baffles 52 are divided into multiple groups. The baffles 52 are arranged in groups along the axis of the fixed disk 51, and the baffles 52 in each group are located in the same layer, which can make the size of the variable diameter structure thinner.

[0065] In some embodiments, the baffle 52 has an arc-shaped splicing portion on the side close to the axis of the fixed disk 51, and the edge of the arc-shaped splicing portion facing the fixed disk 51 is arc-shaped; in the variable diameter structure formed by splicing multiple baffles 52, the outer contour of the through hole is a closed figure formed by connecting multiple arc segments end to end.

[0066] In one possible implementation, the cross-section of the first inner cavity 12 (a cross-section perpendicular to the axis of the fixed disk 51) is circular, the cross-section of the second inner cavity 13 (a cross-section perpendicular to the axis of the fixed disk 51) is circular, and the outer contour of the fixed disk 51 is also circular. Because a circular shape does not adversely affect the flow field compared to a square shape, the through-holes in the fixed disk 51 are also circular. It is understood that to prevent the shape of the through-holes in the variable diameter structure from adversely affecting the flow field, it is necessary to ensure that the through-holes remain approximately circular during the movement of the baffle 52. The edge of the arcuate joint on the baffle 52 closest to the axis of the fixed disk 51 is defined as the inner edge of the baffle 52. The inner edges of all the baffles 52 are arc-shaped, and all the baffles 52 are evenly arranged in a ring along the axis of the fixed disk 51, so that the through hole formed by splicing the inner edges of all the baffles 52 is approximately circular. Since all the baffles 52 rotate at the same time under the drive of the driving assembly, the rotation angles of all the baffles 52 are the same, and the rotating shafts 511 on the fixed disk 51 are also evenly distributed in a ring around the axis of the fixed disk 51. During the rotation of the baffles 52, the rotation paths of all the baffles 52 are centrally symmetrical with the center of the fixed disk 51, so the through hole is always approximately circular during the rotation of the baffles 52.

[0067] It should be noted that the main function of the drive assembly is to drive the baffle 52 to rotate, so any structure that can achieve the above function can be used as the drive assembly in this embodiment, such as a motor or a motor with a transmission pair, etc. Exemplarily, the transmission pair is a gear pair or a pulley combination, etc.

[0068] In some embodiments, the drive assembly includes a drive unit and a transmission gear pair, the transmission gear pair includes a driving gear 54 and a driven gear 55 transmission-connected to the driving gear 54 , the driving gear 54 is transmission-connected to the drive unit, and the driven gear 55 is transmission-connected to the baffle 52 .

[0069] In some embodiments, the drive unit includes an electric motor 53 or a hydraulic motor or a pneumatic motor.

[0070] In one possible implementation, refer to Figure 6The drive assembly includes a drive unit and a transmission gear pair. The drive unit is an electric motor 53, which can also be a hydraulic motor or a pneumatic motor or other power-providing structure. The transmission gear pair includes a driving gear 54 and a driven gear 55. The driven gear 55 and the driving gear 54 can be directly meshed and transmitted, or an intermediate gear can be provided, that is, the driven gear 55 is meshed and transmitted with the driving gear 54 through the intermediate gear. No specific limitation is made here. Figure 6 As shown, combined with Figure 8 The driving gear 54 is installed on the output shaft of the motor 53, the driven gear 55 is directly engaged with the driving gear 54 for transmission, and the driven gear 55 is transmission-connected to the baffle 52 for driving the baffle 52 to rotate around the rotating shaft 511.

[0071] In some embodiments, a first mixer core 6 and a second mixer core 7 arranged along a first direction are provided inside the mixer housing 1, the first mixer core 6 is inserted into one end of the second mixer core 7 to form a first inner cavity 12, and the second mixer core 7 cooperates with the first mixer core 6 to form a second inner cavity 13; the driven gear 55 is provided inside the second mixer core 7, and the driving gear 54 is embedded in the mixer housing 1 and passes through the outer wall of the second mixer core 7 to engage with the driven gear 55.

[0072] In some embodiments, reference Figure 6-Figure 8 The mixer housing 1 includes a first mixer core 6 and a second mixer core 7 arranged along a first direction. The first mixer core 6 is inserted into the second mixer core 7 to form a first inner cavity 12. The second mixer core 7 cooperates with the first mixer core 6 to form a second inner cavity 13. The fixed plate 51 of the diameter reducing mechanism 5 is disposed within the second mixer core 7. One side of the fixed plate 51 is sealedly connected to the second mixer core 7, and the other end is sealedly connected to the first mixer core 6.

[0073] In one possible implementation, refer to Figure 8 The outer contour of the fixed plate 51 is larger than the outer contour of the first mixer core 6 inserted into the second mixer core 7, and smaller than or equal to the inner contour of the second mixer core 7. It will be appreciated that a stop step is provided on the inner wall of the second mixer core 7 for limiting the position of the fixed plate 51 in the first direction. The other side of the fixed plate 51 in the first direction is limited by the contact between the driven gear 55 and the end of the first mixer core 6.

[0074] In some embodiments, the baffle 52 is located between the fixed plate 51 and the driven gear 55; the surface of the driven gear 55 facing the baffle 52 is provided with a shifting shaft 551 corresponding to the baffle 52 one by one, and each baffle 52 is provided with a track groove 522 slidingly engaged with the shifting shaft 551 on the side facing the driven gear 55; or, each baffle 52 is provided with a shifting shaft 551 on the side facing the driven gear 55, and the surface of the driven gear 55 facing the baffle 52 is provided with a track groove 522 slidingly engaged with each shifting shaft 551 respectively.

[0075] In one possible implementation, refer to Figure 8 , and combined with Figures 9-13 The fixed plate 51 is installed in the second inner cavity 13, the driven gear 55 is located on the side of the fixed plate 51 facing the first mixer core 6, and the baffle 52 is located between the fixed plate 51 and the driven gear 55. Figure 14 and Figure 15 As shown, the number of baffles 52 is 9. In order to facilitate the assembly relationship between the baffles 52, the fixed plate 51 and the driven gear 55, Figure 12 Only one baffle 52 is shown. Figure 16-Figure 18 As shown, the fixed plate 51 is provided with a plurality of rotating shafts 511 on the side facing the driven gear 55. Figure 12 Nine rotating shafts 511 are evenly arranged on the middle fixed plate 51, corresponding to the following Figure 12 As shown, the baffle 52 is a plate-like structure with a relatively thin thickness, and is provided with an axis hole 521 that matches the rotating shaft 511. Figure 19 and Figure 20 As shown, the driven gear 55 is provided with a plurality of shifting shafts 551 on the side facing the fixed plate 51. Figure 13 Nine shifting shafts 551 are evenly arranged on the middle fixed plate 51 in a ring shape, corresponding to nine baffles 52 respectively. In order to facilitate the assembly relationship between the baffles 52, the fixed plate 51 and the driven gear 55, Figure 12 Only one baffle 52 is shown. Figure 13 As shown, the baffle 52 is provided with a track groove 522 that cooperates with the toggle shaft 551 and is used to limit the sliding track of the toggle shaft 551 relative to the baffle 52. Figure 12 and Figure 13 After the fixed plate 51, the baffle 52 and the driven gear 55 are assembled, the rotating shaft 511 passes through the shaft hole 521, and the toggle shaft 551 is inserted into the track groove 522. When the driving gear 54 drives the driven gear 55 to rotate, the toggle shaft 551 rotates with the driven gear 55, thereby pushing the baffle 52 to rotate around the rotating shaft 511.

[0076] In some embodiments, the track groove 522 is arc-shaped, and the opening of the arc faces the axis of the fixed disk 51 .

[0077] In one possible implementation, refer to Figure 12The fixed plate 51 and the driven gear 55 are both circular in shape, and the through-hole on the fixed plate 51 is also circular. The driven gear 55 is provided with a hole of the same shape and size as the through-hole on the fixed plate 51 to avoid affecting the flow field. The baffle 52 is provided with an arc-shaped splicing portion on the side facing the axis of the fixed plate 51. The contour line of the edge of the arc-shaped splicing portion on the side facing the axis of the fixed plate 51, that is, the inner edge, is a circular arc. This arc segment is the same as a segment of the circular contour of the through-hole. It can also be understood that when the baffle 52 rotates to a specific position, the orthographic projection of the circular contour of the through-hole on the plane of the fixed plate 51 covers the orthographic projection of the inner edge of the arc-shaped splicing portion on the plane of the fixed plate 51. The track groove 522 on the baffle 52 is an arc-shaped groove with its opening facing the axis of the fixed plate 51. The arc-shaped groove can make the rotation of the baffle 52 driven by the driven gear 55 smoother. Of course, the track groove 522 is not limited to an arc-shaped groove, but can also be a straight groove.

[0078] In some embodiments, when the baffle 52 is provided with a track groove 522 , the track groove 522 is a through groove, and the fixed plate 51 is provided with an annular groove 512 on the side facing the baffle 52 , and the shifting shaft 551 passes through the track groove 522 and slides in cooperation with the annular groove 512 .

[0079] In one possible implementation, the track groove 522 on the baffle 52 is an arc-shaped groove, but since the baffle 52 is relatively thin, in order to prevent the driving shaft 551 from being disconnected from the track groove 522, the track groove 522 is set as a through groove, and an annular groove 512 is set on the fixed plate 51 to slide with the driving shaft 551 passing through the track groove 522.

[0080] It is understandable that, referring to Figure 6 、 Figure 8 、 Figure 12 and Figure 13 When the driven gear 55 is driven by the motor 53 and the driving gear 54, the shifting shaft 551 on the driven gear 55 rotates within the annular groove 512 of the fixed plate 51. At the same time, because the shifting shaft 551 on the driven gear 55 passes through the track groove 522 on the baffle 52, it drives the baffle 52 to rotate about the rotating shaft 511 on the fixed plate 51. When the driven gear 55 rotates clockwise, the nine baffles 52 contract inward, reducing the flow area; when the driven gear 55 rotates counterclockwise, the nine baffles 52 expand outward, increasing the flow area. Both contraction and expansion have their limits, as shown below. Figure 21 and Figure 22 shown.

[0081] The present invention uses the variable diameter mechanism 5 to adjust the flow area to accommodate changes in natural gas engine operating conditions. For example, at the rated engine load, the intake air flow is sufficiently high to establish a sufficient pressure differential through the Venturi structure (the first mixer core 6 is a Venturi structure), ensuring accurate air volume calculation. However, when the engine load is low, the intake air volume is small, and the pressure differential cannot be established, resulting in reduced air volume calculation accuracy. In this case, reducing the flow area to forcibly establish the pressure differential can ensure accurate air volume calculation. Changing the flow area can also control the exhaust gas recirculation (EGR) rate: a smaller flow area increases the pressure differential and the EGR rate; conversely, the EGR rate decreases.

[0082] In a second aspect, an embodiment of the present invention further provides an engine, further comprising any mixer as described in the embodiment of the first aspect.

[0083] Obviously, those skilled in the art may make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is intended to include such modifications and variations.

Claims

1. A mixer, characterized in that: include: Mixer housing and gas connections; The mixer housing has an air inlet, a first inner cavity, a second inner cavity and a mixed gas outlet which are sequentially connected along a first direction, the first inner cavity and the second inner cavity are connected via a diameter reducing mechanism; the gas connector is connected to the first inner cavity; The diameter-changing mechanism includes a fixed plate, a baffle, and a drive assembly; the fixed plate is relatively fixed to the mixer housing, and the axis direction of the fixed plate is parallel to the first direction, and the fixed plate has a through hole connecting the first inner cavity and the second inner cavity; the baffle is rotatably mounted on the fixed plate via a rotating shaft, and is used to cover or expose the through hole; the drive assembly is in transmission connection with the baffle, and is used to drive the baffle to rotate around the rotating shaft to adjust the shielding area of ​​the through hole by the baffle; The driving assembly includes a driving part and a transmission gear pair, wherein the transmission gear pair includes a driving gear and a driven gear transmission-connected to the driving gear, the driving gear is transmission-connected to the driving part, and the driven gear is transmission-connected to the baffle; The blocking piece is located between the fixed plate and the driven gear; The driven gear is provided with a toggle shaft corresponding to each of the blocking pieces on a side thereof facing the blocking piece, and each of the blocking pieces is provided with a track groove slidingly matched with the toggle shaft on a side thereof facing the driven gear; or Each of the baffles is provided with a shifting shaft on the side facing the driven gear, and the surface of the driven gear on the side facing the baffle is provided with a track groove that slides with each of the shifting shafts; The mixer housing is provided with a first mixer core and a second mixer core arranged along a first direction, the first mixer core is inserted into the second mixer core to form the first inner cavity, and the second mixer core cooperates with the first mixer core to form the second inner cavity; The driven gear is arranged inside the second mixer core, and the driving gear is embedded in the mixer housing and penetrates the outer wall of the second mixer core to engage with the driven gear.

2. The mixer according to claim 1, characterized in that There are multiple baffles, which are arranged in a ring around the axis of the fixed disk and spliced ​​to form a variable diameter structure. The edges of the multiple baffles are spliced ​​in the middle of the variable diameter structure to form a through hole connected to the through hole; The driving assembly is used to drive at least one baffle to rotate around its corresponding rotation axis along a second direction to adjust the size of the through hole, wherein the second direction is a clockwise direction or a counterclockwise direction.

3. The mixer according to claim 2, characterized in that The plurality of baffles are evenly distributed around the axis of the fixed disk; and / or, The plurality of baffles are arranged in sequence along the axis of the fixed disk.

4. The mixer according to claim 3, characterized in that The baffle has an arc-shaped splicing portion on the side close to the fixed plate axis, and the edge of the arc-shaped splicing portion facing the fixed plate is arc-shaped; in the variable diameter structure formed by splicing multiple baffles, the outer contour of the through hole is a closed figure formed by connecting multiple arc segments end to end.

5. The mixer according to any one of claims 1 to 4, characterized in that The track groove is arc-shaped, and the arc-shaped opening faces the axis of the fixed plate; or, When the baffle is provided with a track groove, the track groove is a through groove, and the fixed plate is provided with an annular groove on a side facing the baffle, and the shifting shaft passes through the track groove and is slidably engaged with the annular groove.

6. The mixer according to any one of claims 1 to 4, characterized in that The driving part includes an electric motor, a hydraulic motor or a pneumatic motor.

7. An engine, characterized in that: Comprising the mixer according to any one of claims 1-6.

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