Carburetor control system, carburetor control method and multi-fuel engine

Abstract

The invention discloses a carburetor control system, a carburetor control method and a multi-fuel engine, the control system is applied to a carburetor with a plurality of fuel gas inlet channels, and the control system comprises a fuel change-over switch, a fuel type detection circuit, a power detection module and a control module, a fuel type detection circuit outputs a corresponding fuel type signal to a control module according to the current gear of the fuel change-over switch; a current output power signal of the engine is detected through the power detection module and sent to the control module; a control module outputs a corresponding throttle valve opening degree control signal to a driving motor according to a fuel type signal and a current output power signal so as to adjust the opening degree of a throttle valve to a target opening degree; therefore, the amount of fuel gas output to the engine cylinder body by the carburetor through the plurality of fuel gas inlet channels can meet the power requirement under the current load of the engine. When the multi-fuel engine uses gas fuel, the multi-fuel engine can meet different load working conditions so as to guarantee stable operation of the multi-fuel engine.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-fuel engines, and in particular to a carburetor control system and a control method thereof, and a multi-fuel engine. Background Art

[0002] A multi-fuel engine is an engine that can use a variety of different fuels for combustion, which can reduce dependence on a single fuel and reduce the consumption of limited resources. At present, there are mainly two types of multi-fuel engines according to the fuel type: one is a gas multi-fuel engine, which uses at least two of the gas fuels such as LPG (liquefied petroleum gas), NG (natural gas), hydrogen, coal gas, biogas, etc. for combustion; the other is a gas-fuel mixed multi-fuel engine, which uses one or more gas fuels (such as LPG, NG, etc.) and a liquid fuel (such as gasoline, etc.) for combustion.

[0003] A multi-fuel engine is usually provided with a fuel switching switch. Before the engine is started, the fuel switching switch is usually used to switch the type of fuel to be supplied to the carburetor of the engine. Only one fuel is selected when the engine is working.

[0004] For a multi-fuel engine, not only is its carburetor required to automatically proportion the fuel and output a corresponding amount of mixed gas according to different working conditions, but its carburetor is also required to automatically proportion the gas and output a corresponding amount of mixed gas according to different working conditions.

[0005] However, the carburetor of the multi-fuel engine in the prior art usually directly inserts the gas intake pipe into the throat of the carburetor. Therefore, it has only one gas intake passage to supply gas, which makes it impossible to accurately proportion the gas intake amount according to different working conditions, resulting in unstable engine operation. When the engine is in a low-load condition, there will be excessive gas supply, excessive fuel consumption, and low fuel combustion efficiency, which is not conducive to energy conservation and emission reduction. When the engine is in a high-load condition, there will be a problem of insufficient gas intake, resulting in an inability to meet power requirements.

[0006] Therefore, how to enable a multi-fuel engine to meet different load conditions when using gaseous fuel to ensure stable operation of the multi-fuel engine is a problem that needs to be solved urgently. Summary of the invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art, and in particular innovatively proposes a carburetor control system and a control method thereof and a multi-fuel engine, so that the multi-fuel engine can meet different load conditions when using gas fuel, thereby ensuring the stable operation of the multi-fuel engine.

[0008] In order to achieve the above-mentioned object of the present invention, according to a first aspect of the present invention, the present invention provides a carburetor control system, wherein the control system is applied to a carburetor having a plurality of gas intake passages.

[0009] The control system includes a fuel switching switch, a fuel type detection circuit, a power detection module and a control module, wherein the fuel switching switch is connected to a signal input end of the fuel type detection circuit, a signal output end of the fuel type detection circuit and a signal output end of the power detection module are respectively connected to a signal input end of the control module, and a signal output end of the control module is connected to a signal input end of a driving motor of the throttle valve, wherein:

[0010] The fuel type detection circuit is used to output a corresponding fuel type signal to the control module according to the current gear position of the fuel switching switch;

[0011] The power detection module is used to detect the current output power signal of the engine and send it to the control module;

[0012] The control module is used to output a corresponding throttle opening control signal to the drive motor according to the fuel type signal and the current output power signal, so as to adjust the throttle opening to a target opening, so that the amount of gas output by the carburetor to the engine cylinder through the multiple gas intake channels can meet the power requirement under the current load of the engine.

[0013] Preferably, the carburetor comprises a carburetor body, on which a main air intake passage for mixing air and gas, a gas matching chamber for matching gas to the main air intake passage, and a gas intake interface for delivering gas to the gas matching chamber are provided, wherein:

[0014] The main air intake passage is arranged through the carburetor body, the air intake end of the main air intake passage is rotatably provided with a choke for controlling air to enter the main air intake passage, and the air outlet end of the main air intake passage is rotatably provided with a throttle for controlling a mixed gas of air and fuel gas to enter the engine cylinder.

[0015] The gas inlet end of the gas inlet interface is connected to the gas supply device, and the gas outlet end of the gas inlet interface is communicated with the gas matching cavity.

[0016] The multiple gas intake channels include a main gas intake channel, an auxiliary gas intake channel and a low-load gas intake channel arranged on the carburetor body, the intake ends of the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel are all connected to the gas matching cavity, the outlet ends of the main gas intake channel and the auxiliary gas intake channel are all connected to the main intake channel and are both located between the choke and the throttle, the outlet end of the low-load gas intake channel is connected to the main intake channel and is located on the side of the throttle close to the outlet end of the main intake channel, wherein the diameter of the main gas intake channel is greater than the diameter of the auxiliary gas intake channel, and the diameter of the auxiliary gas intake channel is greater than the diameter of the low-load gas intake channel.

[0017] Preferably, the power detection module includes a rotation speed sensor and a signal processing unit, the signal output end of the rotation speed sensor is connected to the signal input end of the signal processing unit, and the signal output end of the signal processing unit is connected to the signal input end of the control module, wherein:

[0018] The speed sensor is used to detect a current speed signal of the engine, and the signal processing unit is used to convert the current speed signal into a corresponding current output power signal according to a speed-power characteristic curve of the engine.

[0019] Preferably, the distance between the inlet end of the main gas inlet channel and the outlet end of the gas inlet interface is greater than the distance between the inlet end of the auxiliary gas inlet channel and the outlet end of the gas inlet interface, and the distance between the inlet end of the auxiliary gas inlet channel and the outlet end of the gas inlet interface is greater than the distance between the inlet end of the low-load gas inlet channel and the outlet end of the gas inlet interface.

[0020] Preferably, the gas inlet ends of the main gas inlet channel and the auxiliary gas inlet channel are opened on the bottom wall of the gas matching cavity, and the gas inlet end of the low-load gas inlet channel is opened on the side wall of the gas matching cavity;

[0021] A throat portion is provided in the middle of the main air intake channel, the diameter of which is smaller than the diameter of the channels of the main air intake channel located at both ends of the throat portion, and the outlet ends of the main gas intake channel and the auxiliary gas intake channel are both located on the throat portion.

[0022] Preferably, the gas matching chamber is located above the main air inlet passage;

[0023] The main gas intake channel is vertically arranged, and the gas outlet end of the main gas intake channel is located on the inner wall just above the main intake channel; the rotation center lines of the choke and the throttle are parallel to the axis of the main gas intake channel;

[0024] The auxiliary gas intake passage is arranged at an angle, and the axis of the auxiliary gas intake passage is perpendicular to and intersects with the axis of the main intake passage.

[0025] According to a second aspect of the present invention, the present invention provides an engine, the engine comprising any carburetor control system according to the first aspect of the present invention.

[0026] According to a third aspect of the present invention, the present invention provides a control method for any of the above carburetor control systems, the control method comprising the following steps:

[0027] S1, the control module obtains the fuel type signal output by the fuel type detection circuit and the current output power signal output by the power detection module;

[0028] S2, the control module outputs a corresponding throttle opening control signal to the drive motor according to the fuel type signal and the current output power signal to adjust the throttle opening to a target opening, so that the amount of gas output by the carburetor to the engine cylinder through the multiple gas intake channels can meet the power requirement under the current load of the engine.

[0029] Preferably, step S2 comprises:

[0030] S21, when the fuel type signal indicates that the fuel currently used by the engine is gas fuel, searching the engine parameter control database for a throttle opening calculation model that matches the currently used fuel type according to the fuel type signal, wherein the engine parameter control database pre-stores a plurality of throttle opening calculation models of different types of gas fuels, and the gas fuel types correspond to the throttle opening calculation models one by one;

[0031] S22, inputting the current output power signal into the throttle opening calculation model obtained by searching, to obtain a target opening value matching the current output power signal;

[0032] S23, generating a corresponding throttle opening control signal based on the target opening value;

[0033] S24, controlling the drive motor based on the throttle opening control signal to adjust the throttle opening to a target opening, so that the amount of gas output from the carburetor to the engine cylinder through the multiple gas intake passages can meet the power requirement under the current load of the engine.

[0034] Preferably, before step S1, the control method further comprises the following steps:

[0035] S01, experimentally measuring the intake volumes of the gas intake main channel, the gas intake auxiliary channel, and the low-load gas intake channel corresponding to different throttle openings under a preset gas type;

[0036] S02, according to the respective intake volumes of the gas intake main channel, the gas intake auxiliary channel and the low-load gas intake channel corresponding to different throttle openings under the preset gas type, the throttle opening is used as the horizontal coordinate and the intake volume is used as the vertical coordinate, and the throttle opening-intake volume characteristic curves corresponding to the gas intake main channel, the gas intake auxiliary channel and the low-load gas intake channel are drawn;

[0037] S03, according to the throttle opening-intake volume characteristic curves corresponding to the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel, the throttle opening is used as the independent variable, and the gas intake volumes of the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel are used as the dependent variables, respectively, to construct a gas intake volume calculation model corresponding to the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel under the preset gas type;

[0038] S04, calculating the total amount of gas intake of the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel at different throttle openings according to the gas intake amount calculation model corresponding to the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel under the preset gas type;

[0039] S05, according to the total amount of gas intake corresponding to different throttle openings under the preset gas type, a throttle opening-total amount of gas intake characteristic curve corresponding to the preset gas type is drawn, with the throttle opening as the horizontal coordinate and the total amount of gas intake as the vertical coordinate;

[0040] S06, constructing a gas intake total amount calculation model based on the throttle opening-gas intake total amount characteristic curve corresponding to the preset gas type, taking the throttle opening as an independent variable and the gas intake total amount as a dependent variable;

[0041] S07, constructing a functional relationship between the engine power and the optimal gas intake volume of the preset gas type;

[0042] S08, taking the total gas intake amount as the optimal gas intake amount of the preset gas type, and constructing a throttle opening calculation model for the preset fuel type based on a functional relationship between the engine power and the optimal gas intake amount of the preset gas type and the total gas intake amount calculation model.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] The present invention provides a plurality of gas intake passages on the carburetor. Meanwhile, the control system provides a fuel switching switch, a fuel type detection circuit, a power detection module and a control module. The fuel type detection circuit outputs a corresponding fuel type signal to the control module according to the current gear position of the fuel switching switch. The power detection module detects the current output power signal of the engine and sends it to the control module. The control module outputs a corresponding throttle opening control signal to the drive motor according to the fuel type signal and the current output power signal to adjust the throttle opening to the target opening, so that the amount of gas output from the carburetor to the engine cylinder through the plurality of gas intake passages can meet the power demand under the current load of the engine, so that the multi-fuel engine can meet different load conditions when using gas fuel, and effectively ensure the stable operation of the multi-fuel engine.

[0045] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0047] Figure 1 It is a circuit principle block diagram of a carburetor control system in a preferred embodiment of the present invention;

[0048] Figure 2 is a perspective view of a carburetor in a preferred embodiment of the present invention;

[0049] Figure 3 for Figure 1 A cross-sectional view of the gas matching cavity of the middle carburetor;

[0050] Figure 4 for Figure 3 A top view of

[0051] Figure 5 for Figure 3 A cross-sectional view of the gas intake auxiliary passage of the middle carburetor;

[0052] Figure 6 for Figure 1 A schematic diagram of the internal structure of the main intake passage of a carburetor;

[0053] Figure 7 A flow chart of a control method of a carburetor control system in a preferred embodiment of the present invention;

[0054] Figure 8 A flow chart of a method for controlling the throttle opening by a control module in a preferred embodiment of the present invention;

[0055] Fig. 9 A flow chart of a method for constructing a throttle opening calculation model in a preferred embodiment of the present invention;

[0056] Fig.10 It is a characteristic curve diagram of the intake amount of each gas intake passage of the engine and the carburetor when the fuel type is LPG in a preferred embodiment of the present invention;

[0057] Fig.11 A characteristic curve diagram of the intake amount of each gas intake passage of the engine and the carburetor when the fuel type is NG in a preferred embodiment of the present invention;

[0058] Fig.12 A characteristic curve diagram of the throttle opening-intake amount corresponding to the main gas intake passage when the fuel type is NG in a preferred embodiment of the present invention;

[0059] Fig.13 A throttle opening-intake volume characteristic curve diagram corresponding to the auxiliary gas intake passage when the fuel type is NG in a preferred embodiment of the present invention;

[0060] Fig.14 This is a throttle opening-intake volume characteristic curve corresponding to the low-load gas intake passage when the fuel type is NG in a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0061] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0062] Those skilled in the art will appreciate that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined.

[0063] like Figure 1 As shown, the embodiment of the present invention provides an application Figure 2-6The control system of the carburetor with multiple gas intake channels shown in the figure may include a fuel switching switch 1, a fuel type detection circuit 2, a power detection module 3 and a control module 4, the fuel switching switch 1 is connected to the signal input end of the fuel type detection circuit 2, the signal output end of the fuel type detection circuit 2 and the signal output end of the power detection module 3 are respectively connected to the signal input end of the control module 4, and the signal output end of the control module 4 is connected to the signal input end of the drive motor 1051 of the throttle 105, wherein:

[0064] The fuel type detection circuit 2 is used to output a corresponding fuel type signal to the control module 4 according to the current gear position of the fuel switching switch 1;

[0065] The power detection module 3 is used to detect the current output power signal of the engine and send it to the control module 4;

[0066] The control module 4 is used to output the corresponding throttle 105 opening control signal to the drive motor 1051 according to the fuel type signal and the current output power signal, so as to adjust the opening of the throttle 105 to the target opening, so that the amount of gas output by the carburetor to the engine cylinder through multiple gas intake channels can meet the power requirement under the current load of the engine.

[0067] The working principle of the carburetor control system in this embodiment is as follows:

[0068] During the operation of the engine, the fuel type detection circuit 2 outputs the corresponding fuel type signal to the control module 4 according to the current gear position of the fuel switching switch 1, the power detection module 3 detects the current output power signal of the engine and sends it to the control module 4, and the control module 4 outputs the corresponding throttle valve 105 opening control signal to the drive motor 1051 according to the fuel type signal and the current output power signal to adjust the opening of the throttle valve 105 to the target opening, so that the amount of gas output by the carburetor to the engine cylinder through multiple gas intake channels can meet the power demand under the current load of the engine.

[0069] The embodiment of the present invention provides a plurality of gas intake channels on the carburetor. Meanwhile, the control system provides a fuel switching switch 1, a fuel type detection circuit 2, a power detection module 3 and a control module 4. The fuel type detection circuit 2 outputs a corresponding fuel type signal to the control module 4 according to the current gear position of the fuel switching switch 1. The power detection module 3 detects the current output power signal of the engine and sends it to the control module 4. The control module 4 outputs a corresponding throttle valve 105 opening control signal to the drive motor 1051 according to the fuel type signal and the current output power signal, so as to adjust the opening of the throttle valve 105 to the target opening, so that the amount of gas output from the carburetor to the engine cylinder through the plurality of gas intake channels can meet the power requirement under the current load of the engine, so that the multi-fuel engine can meet different load conditions when using gas fuel, and effectively ensure the stable operation of the multi-fuel engine.

[0070] like Figure 2-6 As shown, in one embodiment, the carburetor includes a carburetor body 10, on which a main air intake passage 101 for mixing air and gas, a gas matching chamber 102 for matching gas to the main air intake passage 101, and a gas intake interface 103 for delivering gas to the gas matching chamber 102 are provided, wherein:

[0071] The main air intake channel 101 is provided through the carburetor body 10. A choke 104 is rotatably provided at the air intake end of the main air intake channel 101 for controlling the air to enter the main air intake channel 101. A throttle 105 is rotatably provided at the air outlet end of the main air intake channel 101 for controlling the mixed gas of air and fuel gas to enter the engine cylinder.

[0072] The gas inlet end of the gas inlet interface 103 is connected to the gas supply device, and the gas outlet end of the gas inlet interface 103 is connected to the gas matching cavity 102.

[0073] The multiple gas intake channels include a main gas intake channel 106, an auxiliary gas intake channel 107 and a low-load gas intake channel 108 arranged on the carburetor body 10, the intake ends of the main gas intake channel 106, the auxiliary gas intake channel 107 and the low-load gas intake channel 108 are all connected to the gas matching cavity 102, the outlet ends of the main gas intake channel 106 and the auxiliary gas intake channel 107 are all connected to the main intake channel 101 and are both located between the choke 104 and the throttle 105, the outlet end of the low-load gas intake channel 108 is connected to the main intake channel 101 and is located on the side of the throttle 105 close to the outlet end of the main intake channel 101, wherein the diameter of the main gas intake channel 106 is greater than the diameter of the auxiliary gas intake channel 107, and the diameter of the auxiliary gas intake channel 107 is greater than the diameter of the low-load gas intake channel 108.

[0074] After the engine runs and generates negative pressure, air is sucked from the main intake passage 101. The air in the main intake passage 101 flows to generate negative pressure. The gas of the gas supply device enters the gas matching chamber 102 through the gas intake interface 103. Under the action of the negative pressure in the main intake passage 101, the gas in the gas matching chamber 102 is sucked into the main intake passage 101 through the gas intake main passage 106, the gas intake auxiliary passage 107 and the low-load gas intake passage 108. The gas is mixed with air and then transported to the engine through the throttle valve 105 for combustion. In this process, the amount of gas entering the main intake passage 101 from the gas matching chamber 102 is controlled by changing the opening of the throttle valve 105, that is, the gas intake amount at the gas intake main passage 106, the gas intake auxiliary passage 107 and the low-load gas intake passage 108 is controlled. Due to the different positions and diameters of the main gas intake channel 106, the auxiliary gas intake channel 107 and the low-load gas intake channel 108, at different throttle valve 105 openings, the amount of gas in the gas matching chamber 102 delivered from the main gas intake channel 106, the auxiliary gas intake channel 107 and the low-load gas intake channel 108 to the main intake channel 101 will change dynamically, thereby structurally supporting the technical support for dynamic matching of the gas intake amount according to the engine load, and cooperating with the control strategy of the control system, so that the amount of gas output by the carburetor to the engine cylinder through multiple gas intake channels can meet the power demand under the current load of the engine, so that the multi-fuel engine can meet different load conditions when using gas fuel, effectively ensuring the stable operation of the multi-fuel engine.

[0075] It should be noted that the setting of the low-load gas intake passage 108 allows the gas in the gas matching chamber 102 to flow directly into the engine without passing through the throttle valve 105, thereby ensuring the gas supply under the engine idle condition.

[0076] In one embodiment, the power detection module 3 includes a speed sensor 31 and a signal processing unit 32, the signal output end of the speed sensor 31 is connected to the signal input end of the signal processing unit 32, and the signal output end of the signal processing unit 32 is connected to the signal input end of the control module 4, wherein:

[0077] The speed sensor 31 is used to detect the current speed signal of the engine, and the signal processing unit 32 is used to convert the current speed signal into a corresponding current output power signal according to the speed-power characteristic curve of the engine.

[0078] In this embodiment, the current speed signal of the engine is detected by the speed sensor 31 provided by the engine, thereby reducing the number of engine components, and the signal processing unit 32 is provided to convert the current speed signal into a corresponding current output power signal according to the speed-power characteristic curve of the engine, thereby realizing the detection of the engine power.

[0079] It should be noted that the speed-power characteristic curve is drawn through experiments based on engine performance. It is usually set and stored in the engine controller (such as engine ECU) before the engine leaves the factory. In the speed-power characteristic curve, there is a one-to-one correspondence between speed and power. Therefore, by detecting the current speed signal of the engine, the corresponding current output power signal can be found in the speed-power characteristic curve.

[0080] In one embodiment, the distance between the inlet end of the main gas inlet channel 106 and the outlet end of the gas inlet interface 103 is greater than the distance between the inlet end of the auxiliary gas inlet channel 107 and the outlet end of the gas inlet interface 103, and the distance between the inlet end of the auxiliary gas inlet channel 107 and the outlet end of the gas inlet interface 103 is greater than the distance between the inlet end of the low-load gas inlet channel 108 and the outlet end of the gas inlet interface 103.

[0081] In this embodiment, since the distances between the main gas inlet channel 106, the auxiliary gas inlet channel 107 and the low-load gas inlet channel 108 and the gas inlet interface 103 increase successively, the gas outlet end of the gas inlet interface 103 inputs gas to the gas matching cavity 102 and will first pass through the inlet of the low-load gas inlet channel 108, and then reach the inlet of the auxiliary gas inlet channel 107, and finally reach the inlet of the main gas inlet channel 106. Based on the arrangement of the positions and diameters of the gas intake channels, when the engine is running at a low load, the throttle valve 105 is opened at a small degree, and negative pressure is generated in the main intake channel 101. Since the diameters of the main gas intake channel 106, the auxiliary gas intake channel 107, and the low-load gas intake channel 108 are successively reduced, and the distances from the intake end of the gas intake interface 103 are successively increased, the negative pressure generated in the low-load gas intake channel 108 is greater than the negative pressure generated in the auxiliary gas intake channel 107, and the negative pressure generated in the auxiliary gas intake channel 107 is greater than the negative pressure generated in the main gas intake channel 106. At this time, the gas in the gas matching chamber 102 mainly enters the main intake channel 101 from the low-load gas intake channel 108, and part of the gas enters the main intake channel 101 from the gas intake auxiliary channel 107; as the load increases, the throttle valve 105 opening will also increase, and the gas entering from the gas intake main channel 106 and the gas intake auxiliary channel 107 will increase, thereby drawing more gas into the main intake channel 101 to mix with the air, thereby increasing the total gas intake volume, and then the mixed gas is input into the engine for combustion, so that the engine can work stably when running at high load.

[0082] In one embodiment, the intake ends of the main gas intake channel 106 and the auxiliary gas intake channel 107 are opened on the bottom wall of the gas matching cavity 102, and the intake end of the low-load gas intake channel 108 is opened on the side wall of the gas matching cavity 102;

[0083] A throat portion 1011 is provided in the middle of the main air intake channel 101. The diameter of the throat portion 1011 is smaller than the diameter of the channels of the main air intake channel 101 located at both ends of the throat portion 1011. The outlet ends of the main gas intake channel 106 and the auxiliary gas intake channel 107 are both located on the throat portion 1011.

[0084] In this embodiment, the ends of the main gas intake channel 106 and the auxiliary gas intake channel 107 that are connected to the main intake channel 101 are located on the throat portion 1011, so that the main gas intake channel 106 and the auxiliary gas intake channel 107 can obtain a greater negative pressure when the engine is running, thereby more stably drawing gas from the gas matching cavity 102.

[0085] In one embodiment, the gas matching cavity 102 is located above the main air inlet passage 101;

[0086] The main gas inlet channel 106 is vertically arranged, and the gas outlet end of the main gas inlet channel 106 is located on the inner wall just above the main gas inlet channel 101; the rotation center lines of the choke 104 and the throttle 105 are parallel to the axis of the main gas inlet channel 106;

[0087] The auxiliary gas intake passage 107 is tilted, and the axis of the auxiliary gas intake passage 107 is perpendicular to and intersects with the axis of the main intake passage 101 .

[0088] Specifically, the end of the gas intake auxiliary channel 107 connected to the main intake channel 101 is located on the side of the top of the main intake channel 101, and the trajectory of the gas entering the gas matching cavity 102 through the gas intake interface 103 and then arriving at the intake end of the gas intake main channel 106 after flowing through the intake end of the gas intake auxiliary channel 107 is roughly perpendicular to the axis of the main intake channel 101.

[0089] In this embodiment, when the engine load increases, the throttle 105 rotates, and outside air enters the main intake passage 101 from both sides of the choke 104. At this time, the amount of air flowing through the main gas intake passage 106 located directly above the main intake passage 101 is small, while the amount of air flowing through the auxiliary gas intake passage 107 located on the upper side of the main intake passage 101 is large, thereby making the negative pressure at the auxiliary gas intake passage 107 larger, so that the auxiliary gas intake passage 107 can draw more gas from the gas matching chamber 102, and as the opening of the throttle 105 increases, the gas in the gas matching chamber 102 changes from mainly entering the main intake passage 101 from the auxiliary gas intake passage 107 at the beginning to the gas entering the main intake passage 101 from the main gas intake passage 106 and the auxiliary gas intake passage 107, until the throttle 105 is opened to the maximum, and the gas mainly enters the main intake passage 101 from the main gas intake passage 106.

[0090] like Fig.10 , Fig.11 As shown, it is a characteristic curve diagram of the intake amount of each gas intake channel of the engine and the carburetor when the fuel types are LPG and NG respectively in a preferred embodiment of the present invention. It can be seen from the total gas intake curve in the figure that when the engine is in different load conditions, the total gas intake amount can be controlled relatively linearly by changing the throttle opening and coordinating the position setting and diameter difference of the gas intake main channel, the gas intake auxiliary channel and the low-load gas intake channel, so that the multi-fuel engine can meet different load conditions when using gas fuel, thereby ensuring the stable operation of the multi-fuel engine.

[0091] An embodiment of the present invention further provides a multi-fuel engine, which includes the carburetor control system in any of the above embodiments of the present invention.

[0092] The working principle of the multi-fuel engine in this embodiment is the same as the working principle of the carburetor control system in the above embodiment, which will not be described in detail here. Since the multi-fuel engine in this embodiment adopts the carburetor control system in the above embodiment, the multi-fuel engine has the same beneficial effects as the carburetor control system, and can also enable the multi-fuel engine to meet different load conditions when using gas fuel, thereby ensuring the stable operation of the multi-fuel engine.

[0093] like Figure 7 As shown, the present invention also provides a control method for any of the above carburetor control systems, and the control method may include the following steps:

[0094] S1, the control module obtains the fuel type signal output by the fuel type detection circuit and the current output power signal output by the power detection module;

[0095] S2, the control module outputs a corresponding throttle opening control signal to the drive motor according to the fuel type signal and the current output power signal to adjust the throttle opening to the target opening, so that the amount of gas output by the carburetor to the engine cylinder through multiple gas intake channels can meet the power requirement under the current load of the engine.

[0096] In this embodiment, the control module obtains the fuel type signal output by the fuel type detection circuit and the current output power signal output by the power detection module, and the module outputs the corresponding throttle opening control signal to the drive motor according to the fuel type signal and the current output power signal to adjust the throttle opening to the target opening, so that the amount of gas output by the carburetor to the engine cylinder through multiple gas intake channels can meet the power requirement under the current load of the engine.

[0097] like Figure 8 As shown, in one embodiment, step S2 includes:

[0098] S21, when the fuel type signal indicates that the fuel currently used by the engine is gas fuel, searching the engine parameter control database for a throttle opening calculation model that matches the currently used fuel type according to the fuel type signal, wherein the engine parameter control database pre-stores a plurality of throttle opening calculation models of different types of gas fuels, and the gas fuel types correspond to the throttle opening calculation models one by one;

[0099] S22, inputting the current output power signal into the throttle opening calculation model found out, to obtain a target opening value matching the current output power signal;

[0100] S23, generating a corresponding throttle opening control signal based on the target opening value;

[0101] S24, controlling the drive motor based on the throttle opening control signal to adjust the throttle opening to the target opening, so that the amount of gas output by the carburetor to the engine cylinder through the multiple gas intake channels can meet the power demand under the current load of the engine.

[0102] Specifically, in this embodiment, the throttle opening calculation model corresponding to the fuel type NG (natural gas) is as follows:

[0103] P NG =1.2A-1.8,

[0104] Among them, P NG represents engine power, A represents throttle opening;

[0105] The throttle opening calculation model corresponding to the fuel type LPG (liquefied petroleum gas) is as follows:

[0106] PLPG =0.0077A 2 +0.48A-0.3,

[0107] Among them, P LPG represents engine power, and A represents throttle opening.

[0108] In this embodiment, when the current fuel type of the engine is gas fuel, the throttle opening calculation model that matches the currently used fuel type is searched in the engine parameter control database, and the target throttle opening value is calculated based on the current output power signal through the throttle opening calculation model. In subsequent control, the throttle opening is controlled based on the calculated target opening value, so that the amount of gas output by the carburetor to the engine cylinder through multiple gas intake channels can meet the power demand under the current load of the engine. The control process is simple, and the gas intake volume can be matched more accurately according to the engine power, so that the engine can better adapt to different load conditions.

[0109] like Fig. 9 As shown, in one embodiment, before step S1, the control method further includes the step of constructing a throttle opening calculation model, and the specific process is as follows:

[0110] S01, experimentally measuring the intake volumes of the gas intake main channel, the gas intake auxiliary channel, and the low-load gas intake channel corresponding to different throttle openings under a preset gas type;

[0111] S02, according to the respective intake volumes of the gas intake main channel, the gas intake auxiliary channel and the low-load gas intake channel corresponding to different throttle openings under the preset gas type, the throttle opening is used as the horizontal coordinate and the intake volume is used as the vertical coordinate, and the throttle opening-intake volume characteristic curves corresponding to the gas intake main channel, the gas intake auxiliary channel and the low-load gas intake channel are drawn;

[0112] like Figure 12-14 As shown, when the fuel type is NG, the throttle opening-intake amount characteristic curve corresponding to the main gas intake channel, the throttle opening-intake amount characteristic curve corresponding to the auxiliary gas intake channel, and the throttle opening-intake amount characteristic curve corresponding to the low-load gas intake channel.

[0113] S03, according to the throttle opening-intake volume characteristic curves corresponding to the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel, the throttle opening is used as the independent variable, and the gas intake volumes of the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel are used as the dependent variables, respectively, to construct a gas intake volume calculation model corresponding to the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel under the preset gas type;

[0114] Specifically, in this embodiment, Figure 12-14 The gas intake amount calculation model of the gas intake main channel, the gas intake amount calculation model of the gas intake auxiliary channel, and the gas intake amount calculation model of the low-load gas intake channel corresponding to the throttle opening-intake amount characteristic curve are as follows:

[0115] Gas intake volume calculation model for the main gas intake channel:

[0116] Q Z =K×(0.00002A 2 +0.00448A+0.1422)

[0117] Gas intake volume calculation model for the gas intake auxiliary channel:

[0118] Q M =K×0.0284e 0.0142A

[0119] Gas intake flow calculation model for low-load gas intake passage:

[0120] Q L =K×(0.000016A 2 -0.00234A+0.0836)

[0121] Among them, Q Z , Q M , Q L are the gas intake amounts of the gas intake main channel, the gas intake auxiliary channel and the low-load gas intake channel respectively, A represents the throttle opening, and K represents the correction coefficient.

[0122] It should be noted that the correction coefficient K is related to the engine displacement. When the engine displacement is 500ml, the value of K is 1. When the engine displacement is L, K=L / 500.

[0123] S04, calculating the total amount of gas intake of the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel at different throttle openings according to the gas intake amount calculation model corresponding to the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel under the preset gas type;

[0124] S05, according to the total amount of gas intake corresponding to different throttle openings under the preset gas type, a throttle opening-total amount of gas intake characteristic curve corresponding to the preset gas type is drawn, with the throttle opening as the horizontal coordinate and the total amount of gas intake as the vertical coordinate;

[0125] S06, according to the throttle opening-gas intake total amount characteristic curve corresponding to the preset gas type, the throttle opening is used as the independent variable, and the gas intake total amount is used as the dependent variable to construct a gas intake total amount calculation model;

[0126] S07, constructing a functional relationship between the engine power and the optimal gas intake volume of the preset gas type;

[0127] S08, taking the total amount of gas intake as the optimal gas intake amount of the preset gas type, and constructing a throttle opening calculation model of the preset fuel type based on the functional relationship between the engine power and the optimal gas intake amount of the preset gas type and the gas intake total amount calculation model. Specifically, the functional relationship between the engine power and the optimal gas intake amount of the preset gas type is substituted into the gas intake total amount calculation model, and the throttle opening calculation model of the preset fuel type can be obtained.

[0128] In this embodiment, through the method corresponding to the above-mentioned process, according to the corresponding relationship between the engine power, the total amount of gas intake and the throttle opening under different fuel types, a throttle opening calculation model under different fuel types can be constructed, so that under different powers (loads), by adjusting the throttle opening to the target value, the gas intake amount of the engine can meet the engine power requirement, thereby enabling the multi-fuel engine to meet different load conditions when using gas fuel, and effectively ensuring the stable operation of the multi-fuel engine.

[0129] The present invention implements all or part of the processes in the control method of the carburetor control system of the above embodiment, which can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of each of the above method embodiments can be implemented. The computer program includes computer program code, which can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electric carrier signal and telecommunication signal.

[0130] Those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present invention and form different embodiments. For example, in the claims below, any one of the claimed embodiments may be used in any combination.

[0131] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A carburetor control system, characterized in that: The control system is applied to a carburetor having a plurality of fuel gas intake passages. The control system includes a fuel switching switch, a fuel type detection circuit, a power detection module and a control module, wherein the fuel switching switch is connected to a signal input end of the fuel type detection circuit, a signal output end of the fuel type detection circuit and a signal output end of the power detection module are respectively connected to a signal input end of the control module, and a signal output end of the control module is connected to a signal input end of a driving motor of the throttle valve, wherein: The fuel type detection circuit is used to output a corresponding fuel type signal to the control module according to the current gear position of the fuel switching switch; The power detection module is used to detect the current output power signal of the engine and send it to the control module; The control module is used to output a corresponding throttle opening control signal to the drive motor according to the fuel type signal and the current output power signal, so as to adjust the throttle opening to a target opening, so that the amount of gas output by the carburetor to the engine cylinder through the multiple gas intake channels can meet the power requirement under the current load of the engine.

2. The carburetor control system according to claim 1, characterized in that: The carburetor comprises a carburetor body, on which a main air intake passage for mixing air and gas, a gas matching chamber for matching gas to the main air intake passage, and a gas intake interface for delivering gas to the gas matching chamber are provided, wherein: The main air intake passage is arranged through the carburetor body, the air intake end of the main air intake passage is rotatably provided with a choke for controlling air to enter the main air intake passage, and the air outlet end of the main air intake passage is rotatably provided with a throttle for controlling a mixed gas of air and fuel gas to enter the engine cylinder. The gas inlet end of the gas inlet interface is connected to the gas supply device, and the gas outlet end of the gas inlet interface is communicated with the gas matching cavity. The multiple gas intake channels include a main gas intake channel, an auxiliary gas intake channel and a low-load gas intake channel arranged on the carburetor body, the intake ends of the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel are all connected to the gas matching cavity, the outlet ends of the main gas intake channel and the auxiliary gas intake channel are all connected to the main intake channel and are both located between the choke and the throttle, the outlet end of the low-load gas intake channel is connected to the main intake channel and is located on the side of the throttle close to the outlet end of the main intake channel, wherein the diameter of the main gas intake channel is greater than the diameter of the auxiliary gas intake channel, and the diameter of the auxiliary gas intake channel is greater than the diameter of the low-load gas intake channel.

3. The carburetor control system according to claim 1, characterized in that: The power detection module includes a rotation speed sensor and a signal processing unit, the signal output end of the rotation speed sensor is connected to the signal input end of the signal processing unit, and the signal output end of the signal processing unit is connected to the signal input end of the control module, wherein: The speed sensor is used to detect a current speed signal of the engine, and the signal processing unit is used to convert the current speed signal into a corresponding current output power signal according to a speed-power characteristic curve of the engine.

4. The carburetor control system according to any one of claims 1 to 3, characterized in that: The distance between the air inlet end of the main gas inlet channel and the air outlet end of the gas inlet interface is greater than the distance between the air inlet end of the auxiliary gas inlet channel and the air outlet end of the gas inlet interface, and the distance between the air inlet end of the auxiliary gas inlet channel and the air outlet end of the gas inlet interface is greater than the distance between the air inlet end of the low-load gas inlet channel and the air outlet end of the gas inlet interface.

5. The carburetor control system according to claim 4, characterized in that: The gas inlet ends of the main gas inlet channel and the auxiliary gas inlet channel are opened on the bottom wall of the gas matching cavity, and the gas inlet end of the low-load gas inlet channel is opened on the side wall of the gas matching cavity; A throat portion is provided in the middle of the main air intake channel, the diameter of which is smaller than the diameter of the channels of the main air intake channel located at both ends of the throat portion, and the outlet ends of the main gas intake channel and the auxiliary gas intake channel are both located on the throat portion.

6. The carburetor control system according to claim 5, characterized in that: The gas matching cavity is located above the main air inlet passage; The main gas intake channel is vertically arranged, and the gas outlet end of the main gas intake channel is located on the inner wall just above the main intake channel; the rotation center lines of the choke and the throttle are parallel to the axis of the main gas intake channel; The auxiliary gas intake passage is arranged at an angle, and the axis of the auxiliary gas intake passage is perpendicular to and intersects with the axis of the main intake passage.

7. A multi-fuel engine, characterized in that: A carburetor control system comprising any one of claims 1-6.

8. A control method for a carburetor control system according to any one of claims 1 to 6, characterized in that: The steps include: S1, the control module obtains the fuel type signal output by the fuel type detection circuit and the current output power signal output by the power detection module; S2, the control module outputs a corresponding throttle opening control signal to the drive motor according to the fuel type signal and the current output power signal to adjust the throttle opening to a target opening, so that the amount of gas output by the carburetor to the engine cylinder through the multiple gas intake channels can meet the power requirement under the current load of the engine.

9. The control method of the carburetor control system according to claim 8, characterized in that: Step S2 includes: S21, when the fuel type signal indicates that the fuel currently used by the engine is gas fuel, searching the engine parameter control database for a throttle opening calculation model that matches the currently used fuel type according to the fuel type signal, wherein the engine parameter control database pre-stores a plurality of throttle opening calculation models of different types of gas fuels, and the gas fuel types correspond to the throttle opening calculation models one by one; S22, inputting the current output power signal into the throttle opening calculation model obtained by searching, to obtain a target opening value matching the current output power signal; S23, generating a corresponding throttle opening control signal based on the target opening value; S24, controlling the drive motor based on the throttle opening control signal to adjust the throttle opening to a target opening, so that the amount of gas output from the carburetor to the engine cylinder through the multiple gas intake passages can meet the power requirement under the current load of the engine.

10. The control method of the carburetor control system according to claim 9, characterized in that: Before step S1, the control method further includes the following steps: S01, experimentally measuring the intake volumes of the gas intake main channel, the gas intake auxiliary channel, and the low-load gas intake channel corresponding to different throttle openings under a preset gas type; S02, according to the respective intake volumes of the gas intake main channel, the gas intake auxiliary channel and the low-load gas intake channel corresponding to different throttle openings under the preset gas type, the throttle opening is used as the horizontal coordinate and the intake volume is used as the vertical coordinate, and the throttle opening-intake volume characteristic curves corresponding to the gas intake main channel, the gas intake auxiliary channel and the low-load gas intake channel are drawn; S03, according to the throttle opening-intake volume characteristic curves corresponding to the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel, the throttle opening is used as the independent variable, and the gas intake volumes of the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel are used as the dependent variables, respectively, to construct a gas intake volume calculation model corresponding to the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel under the preset gas type; S04, calculating the total amount of gas intake of the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel at different throttle openings according to the gas intake amount calculation model corresponding to the main gas intake channel, the auxiliary gas intake channel and the low-load gas intake channel under the preset gas type; S05, according to the total amount of gas intake corresponding to different throttle openings under the preset gas type, a throttle opening-total amount of gas intake characteristic curve corresponding to the preset gas type is drawn, with the throttle opening as the horizontal coordinate and the total amount of gas intake as the vertical coordinate; S06, constructing a gas intake total amount calculation model based on the throttle opening-gas intake total amount characteristic curve corresponding to the preset gas type, taking the throttle opening as an independent variable and the gas intake total amount as a dependent variable; S07, constructing a functional relationship between the engine power and the optimal gas intake volume of the preset gas type; S08, taking the total gas intake amount as the optimal gas intake amount of the preset gas type, and constructing a throttle opening calculation model for the preset fuel type based on a functional relationship between the engine power and the optimal gas intake amount of the preset gas type and the total gas intake amount calculation model.

Images