Methanol injection device for methanol engine

Abstract

The utility model relates to the technical field of methanol engines, and discloses a methanol injection device for a methanol engine, which comprises a gas inlet pipe, a plurality of gas inlet channels uniformly distributed along the length direction of the gas inlet pipe, combustion cylinders arranged at the gas outlet ends of the gas inlet channels, and a methanol input pipe arranged on the gas inlet pipe, the methanol input pipe is provided with a plurality of output ports, each output port is provided with a methanol injector, and the injection end of each methanol injector extends to the bottom of the inner cavity of the gas inlet channel so as to inject atomized methanol. The methanol input pipe supplies methanol to the methanol ejectors of the air inlet channels through the output ports, independent ejection of each cylinder is achieved, the ejection ends of the ejectors directly eject atomized methanol into the nose bridge position of the spiral air channel, so that the methanol and air form combustible mixed gas in the spiral air channel, and the combustion effect is improved. The air-fuel ratio deviation and scavenging loss caused by mixing of a traditional header pipe are avoided, the combustion efficiency is remarkably improved, harmful emission is reduced, and the clean combustion requirement is met.

Description

Technical Field

[0001] This utility model relates to the field of methanol engine technology, specifically to a methanol injection device for a methanol engine. Background Technology

[0002] A methanol engine is an internal combustion engine that uses methanol as its primary fuel. Its main advantages include minimal modification to the original engine and lower atmospheric pollution. Methanol is a liquid fuel, and its storage and transportation can utilize petroleum-based systems, thus requiring less infrastructure investment. This technology promotes carbon neutrality and achieves the goals of safe, reliable, sustainable, clean, and low-(zero-)carbon energy.

[0003] Currently, most methanol engines use an intake configuration where methanol is mixed with air in a mixer before the turbocharger, and then enters the intake manifold after being pressurized and cooled. In this configuration, natural gas is introduced under negative pressure, and the mixture is mixed in the manifold. The intake manifold is filled with the mixed gas, and the methanol comes into full contact with the inner wall of the intake manifold, causing significant corrosion to the intake manifold and its internal components. This reduces the service life, poses significant safety hazards, and makes it difficult to accurately control the air-fuel ratio of each cylinder. During the valve overlap angle, some combustion gas escapes with the scavenging air, resulting in low combustion efficiency, poor emission performance, and poor fuel economy, which cannot meet market demands.

[0004] Therefore, there is a need to design and develop a single methanol fuel engine that can achieve independent air intake for each cylinder and can be used as the main methanol engine in the methanol engine field to meet market demand. Utility Model Content

[0005] To address the technical problems existing in the background art, this utility model proposes a methanol injection device for methanol engines.

[0006] The present invention proposes a methanol injection device for a methanol engine, which is mainly applicable to high-horsepower methanol engines. Specifically, it includes an intake pipe, multiple intake channels evenly distributed along the length of the intake pipe, and a combustion cylinder installed at the outlet end of each intake channel.

[0007] The device also includes a methanol input pipe installed on the intake pipe, the methanol input pipe having multiple output ports, and each output port is equipped with a methanol injector, the injection end of the methanol injector extending to the bottom of the inner cavity of the intake duct to spray atomized methanol.

[0008] To address the corrosion and air-fuel ratio control difficulties caused by mixing in the mains of traditional methanol engines, this device independently supplies methanol to each intake manifold through multiple outlets of the methanol input pipe. Each intake manifold corresponds to a methanol injector with the injection end extending deep into the bottom of the inner cavity, directly spraying atomized methanol into the intake manifold. This allows methanol and air to form a premixed air-fuel mixture at the bottom of the intake manifold, preventing the intake pipe from being filled with a combustible mixture, reducing the contact area and time between methanol and the inner wall of the intake manifold, and lowering the risk of corrosion. At the same time, it achieves independent and precise fuel supply to each cylinder, solving the problems of large air-fuel ratio deviation and low combustion efficiency in traditional models.

[0009] As a further optimized solution of this utility model, the methanol injector includes a valve body and an ejector tube. The rear end of the valve body is installed at the output port of the methanol input pipe and is connected to it. The front end of the valve body is fixed to the rear end of the ejector tube. The front end of the ejector tube has an injection port and extends into the air intake passage. A valve stem is slidably mounted in the valve body. The front end of the valve stem slides into the ejector tube and is in sealing contact with the injection port. The rear end of the valve stem is driven by a drive assembly to move along the axial direction of the ejector tube.

[0010] The front end of the ejector tube is equipped with a perforated flat nozzle plate to form an injection port, which is more conducive to the crushing and atomization of methanol fuel.

[0011] The methanol injector adopts a split structure, with the valve body and the ejector tube fixedly connected. The valve stem slides within the ejector tube under the control of the drive assembly. During injection, the valve stem moves backward to open the injection port, and methanol is atomized and sprayed out through the ejector tube. When not injecting, the front end of the valve stem is in sealed contact with the injection port to prevent methanol leakage. This design reduces the direct contact between methanol and the inner wall of the intake manifold. At the same time, by precisely controlling the movement of the valve stem, the injection quantity and injection timing can be accurately adjusted to adapt to the fuel requirements of the engine under different operating conditions.

[0012] As a further optimized solution of this utility model, the drive component includes an electromagnetic coil and a spring installed inside the rear end of the valve body. The electromagnetic coil is opposite to the rear end of the valve stem and the two are connected by the spring. The electromagnetic coil is connected to an external power supply.

[0013] The drive assembly utilizes the interaction between an electromagnetic coil and a spring to achieve a rapid response of the valve stem. When the electromagnetic coil is energized, it generates electromagnetic force to overcome the spring force, pushing the valve stem backward and opening the injection port. When the power is off, the spring returns to its original position, and the front end of the valve stem seals the injection port. This structure has a short response time (millisecond level) and can precisely control the injection pulse width to meet the frequent injection requirements of high-horsepower engines at high speeds. At the same time, the injection quantity can be flexibly adjusted by adjusting the current to ensure precise air-fuel ratio matching.

[0014] As a further optimized solution of this utility model, the inner side of the nozzle opening is a concave spherical surface, and a ball head is installed at the front end of the valve stem, and the ball head is in contact with the spherical surface inside the nozzle opening.

[0015] The concave spherical surface of the injection port and the ball head at the front end of the valve stem form a spherical sealing structure. Compared with a planar seal, the spherical contact area is smaller and the sealing performance is better. It also has an automatic centering function, which can maintain a good seal even if the valve stem is slightly misaligned. This design reduces the risk of methanol leakage, while reducing the wear of the valve stem and injection port, extending the service life of the injector, and ensuring long-term stable operation.

[0016] As a further optimization of this utility model, an installation hole adapted to the valve body is provided on the air intake duct, and the valve body is fixedly installed in the installation hole and sealed by a sealing ring.

[0017] The valve body is fixed to the air intake through the mounting hole, and the sealing ring fills the installation gap to prevent methanol from leaking to the outside of the air intake or to allow outside air to enter. This sealing design enhances the reliability of the device, especially in the case of engine vibration, and can effectively avoid methanol leakage caused by loose installation, thus improving safety. At the same time, it ensures the coaxiality of the injector and the air intake, ensuring the precise injection direction of atomized methanol.

[0018] As a further optimization of this utility model, a sensor for measuring methanol pressure is installed inside the methanol input pipe, and an electrical control wiring harness electrically connected to the sensor is installed on the methanol input pipe. The methanol pressure inside the methanol input pipe is designed to be 0.3-0.5 MPa.

[0019] The sensor monitors the pressure in the methanol input pipe in real time and feeds the data back to the engine ECU via the electronic control harness. The ECU dynamically adjusts the energizing time of the solenoid coil according to the pressure signal to ensure that the injection pressure of each cylinder is stable at 0.3-0.5MPa. This pressure range ensures that the methanol is fully atomized, while avoiding excessive pressure that could damage the injector seals or excessive pressure that could result in poor atomization. This optimizes combustion efficiency and provides real-time data support for precise control of the air-fuel ratio.

[0020] As a further optimization of this utility model, the methanol input pipe is a double-walled track pipe with a methanol input port, which is connected to the output end of the methanol supply equipment.

[0021] The double-walled track pipe structure enhances the strength and sealing of the methanol input pipe. The independent internal channels can withstand higher pressures, avoiding the leakage risk caused by pressure fluctuations in single-walled pipes. The methanol input port is connected to the supply equipment (such as a high-pressure oil pump) to ensure a continuous and stable supply of methanol. The double-walled design also reduces the impact of external heat on the methanol inside the pipe, preventing vapor lock caused by temperature rise, and adapting to the fuel supply needs of high-horsepower engines under high-load conditions.

[0022] As a further optimization of this utility model, the outlet end of the air intake is connected to the combustion cylinder through a spiral air passage, and the injection end of the methanol injector passes through the air intake and extends into the opening of the spiral air passage.

[0023] The spiral intake guides air to form a rotating airflow. The injection end of the methanol injector extends into the opening of the spiral intake, atomizing methanol and rotating air to mix thoroughly, forming a uniform premixed gas. This design utilizes the airflow characteristics of the spiral intake to enhance the turbulent mixing effect of methanol and air. Compared with the traditional straight pipe intake, it can make the mixture more uniform and the combustion more complete, improving the engine's power and economy, while reducing unburned methanol residue and reducing emissions.

[0024] As a further optimization of this utility model, the injection end of the methanol injector extends along the tangential direction of the cylinder head to the inner nose of the spiral air passage to inject atomized methanol fuel. The methanol fuel and air form a premixed gas that enters the combustion cylinder, avoiding the intake passage from being filled with mixed combustible gas, thereby avoiding direct contact between the methanol fuel and the intake passage, reducing the corrosive effect of methanol, and avoiding fuel residue in the intake passage.

[0025] The injection end extends into the nose of the spiral intake manifold along the tangential direction of the cylinder head. It uses the rotation of the airflow to evenly distribute methanol atomized particles within the intake manifold, avoiding direct impact of methanol on the inner wall of the intake manifold. This injection angle design ensures that methanol mixes with air only within the spiral intake manifold, while the intake manifold is mainly composed of air. This significantly reduces the contact area between methanol and the intake manifold, lowering the risk of corrosion. At the same time, it reduces fuel escape during valve overlap, improves combustion efficiency, and reduces safety hazards.

[0026] As a further optimization of this utility model, there are six intake ports, each connected to one of the six combustion cylinders. The methanol input pipe has six output ports, and each of the six output ports is connected to the bottom of the inner cavity of the intake port through a methanol injector, so as to accurately control the air-fuel ratio of each cylinder.

[0027] Designed for high-horsepower six-cylinder engines, the system features six intake ports corresponding to each combustion cylinder, and six independent fuel supply ports on the methanol input pipe. Each injector can independently adjust the injection quantity according to the operating conditions of the corresponding cylinder (such as load and speed), achieving precise control of the air-fuel ratio of each cylinder. Compared with the traditional manifold mixing method, it avoids uneven air-fuel ratio caused by differences in the intake volume of each cylinder. Especially under partial load conditions, it can significantly reduce fuel consumption and harmful emissions, improve engine balance and reliability, and is suitable for high-horsepower applications such as heavy vehicles and ships.

[0028] The methanol injection device for methanol engines proposed in this utility model has the following beneficial effects:

[0029] (I) The methanol input pipe of this utility model supplies methanol to the methanol injectors of each intake manifold through multiple output ports, realizing independent injection of each cylinder. The injection end of the injector extends to the bottom of the inner cavity of the intake manifold, directly spraying atomized methanol into the nose of the spiral intake manifold, so that methanol and air form a combustible mixture in the spiral intake manifold. This avoids the air-fuel ratio deviation and scavenging loss caused by the traditional main pipe mixing, significantly improves combustion efficiency, reduces harmful emissions, meets the requirements of clean combustion, and at the same time avoids large-area contact between methanol fuel and intake manifold, thereby reducing the corrosive effect of methanol on the inner wall of intake manifold, improving service life, and reducing safety hazards.

[0030] (II) In traditional designs, methanol comes into full contact with the inner wall of the intake pipe, which can easily lead to corrosion. The methanol injector of this invention adopts a separate design of valve body and injector tube. The inner side of the injection port is a concave spherical surface and is in sealed contact with the ball head at the front end of the valve stem. When injecting, the valve stem moves backward to open the injection port. When not injecting, the spring resets and seals, reducing the direct contact time between methanol and the inner wall of the intake pipe. At the same time, the sealing ring ensures the sealing between the injector and the mounting hole of the intake channel, further reducing the risk of methanol leakage and corrosion, and extending the service life of the intake pipe and internal components.

[0031] (III) The drive assembly drives the valve stem to move through the cooperation of the electromagnetic coil and the spring. When the electromagnetic coil is energized, it generates electromagnetic force to overcome the spring force, causing the valve stem to move backward and quickly open the injection port. When the power is cut off, the spring returns to its original position, and the valve stem moves forward to close the injection port. The response time is short, and the timing and pulse width of methanol injection can be precisely controlled to meet the rapid adjustment requirements of high-horsepower engines under high speed and high load conditions, ensuring the stability and economy of power output.

[0032] (iv) The methanol input pipe adopts a double-wall structure, forming an independent methanol flow channel inside. It is connected to the supply equipment through the methanol input port and can withstand high fuel pressure. It avoids pressure fluctuations or leakage problems that may occur with single-wall structures. The evenly distributed output ports correspond one-to-one with the injectors of each cylinder, ensuring that the methanol supply to each cylinder is consistent, improving the balance of engine operation, and reducing vibration or power fluctuations caused by uneven fuel supply.

[0033] (v) The methanol injector is fixed to the intake manifold through the mounting hole. The overall layout is compact and occupies little space, making it easy to arrange flexibly in the engine compartment. The methanol input pipe is installed along the length of the intake pipe. The number of output ports can be adjusted according to the number of engine cylinders. It is compatible with high-horsepower methanol engines with different cylinder diameters and numbers. It has strong versatility and can reduce modification costs and installation difficulty.

[0034] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0035] Figure 1 This is a first-view perspective three-dimensional structural diagram of the present invention;

[0036] Figure 2 This is a second-view perspective three-dimensional structural diagram of the present invention;

[0037] Figure 3 This is a schematic diagram of the assembly structure of the methanol injector and the air intake of this utility model.

[0038] Figure 4 This is a partial cross-sectional structural diagram of the methanol injector of this utility model.

[0039] Figure descriptions: 1. Intake pipe; 2. Intake passage; 3. Combustion cylinder; 4. Methanol input pipe; 5. Methanol injector; 51. Valve body; 52. Injector tube; 53. Injection port; 54. Valve stem; 55. Electromagnetic coil; 56. Spring; 57. Ball head; 58. Sealing ring; 6. Electrical control harness; 7. Methanol input port; 8. Spiral air passage. Detailed Implementation

[0040] The embodiments of this utility model are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0041] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0042] This utility model discloses a methanol injection device, which is an improved fuel injection system for high-horsepower methanol engines. Its core lies in the precise injection of atomized methanol into each intake manifold through independent methanol injectors, thereby optimizing combustion efficiency and reducing corrosion risk. Specific implementation details are as follows:

[0043] like Figures 1-3As shown, the device mainly consists of an intake pipe 1, multiple intake channels 2, a combustion cylinder 3, a methanol input pipe 4, and multiple methanol injectors 5. The intake channels 2 are evenly distributed along the length of the intake pipe 1, and the outlet end of each intake channel 2 is connected to a combustion cylinder 3. The methanol input pipe 4 is installed on the intake pipe 1 and has multiple output ports. Each output port is connected to a methanol injector 5. The injection end of the injector extends to the bottom of the inner cavity of the intake channel 2 for direct injection of atomized methanol. Each intake channel 2 corresponds to one methanol injector 5, and the injection quantity can be independently adjusted according to the operating conditions of each cylinder to achieve precise control of the air-fuel ratio, optimize combustion efficiency, and reduce emissions.

[0044] like Figure 4 As shown, the methanol injector 5 adopts a split structure, including a valve body 51 and an ejector tube 52. The valve body 51 is installed at the output port of the methanol input pipe 4 and is fixedly connected to the ejector tube 52. The front end of the ejector tube 52 is provided with an injection port 53 and extends into the air intake duct 2. A valve stem 54 is slidably assembled inside the valve body 51. A ball head 57 is installed at its front end and is in sealing contact with the concave spherical surface of the injection port 53. The rear end of the valve stem 54 is controlled by a drive assembly, which includes an electromagnetic coil 55 and a spring 56. The rapid movement of the valve stem is achieved through the interaction of electromagnetic force and spring force, thereby controlling the injection of methanol.

[0045] During operation, methanol enters through the methanol inlet 7 of the methanol inlet pipe 4 and is distributed to each methanol injector 5 through multiple outlets. When the electromagnetic coil 55 is energized, the generated electromagnetic force overcomes the elastic force of the spring 56, pushing the valve stem 54 backward and opening the injection port 53, allowing methanol to be injected through the ejector tube 52 into the bottom of the inner cavity of the intake passage 2. The injected methanol mixes with the air at the lower end of the inner cavity of the intake passage to form a premixed gas, which then enters the combustion cylinder 3 for combustion. When the electromagnetic coil 55 is de-energized, the spring 56 returns to its original position, pushing the valve stem 54 forward, so that the ball head 57 makes a sealing contact with the injection port 53, preventing methanol leakage.

[0046] Specifically, the methanol input pipe 4 adopts a double-walled track pipe structure to enhance strength and sealing. The internal independent channel can withstand high pressure and avoid leakage risk. A pressure sensor is installed inside the methanol input pipe 4 and is connected to the engine ECU through the electronic control harness 6 to monitor methanol pressure in real time and dynamically adjust injection parameters.

[0047] Specifically, such as Figure 4 As shown, the inner side of the injection port 53 is a concave spherical surface, and the ball head 57 at the front end of the valve stem 54 is in sealing contact with it to form a spherical sealing structure, which reduces the risk of leakage and reduces wear.

[0048] Specifically, such as Figure 3As shown, the intake duct 2 and the combustion cylinder 3 are connected by a spiral air passage 8. The injection end of the methanol injector 5 extends into the opening of the spiral air passage 8, so that the atomized methanol and the rotating air are fully mixed to form a uniform premixed gas and improve combustion efficiency.

[0049] Taking a six-cylinder engine as an example, the six intake ports 2 correspond to the six combustion cylinders 3 respectively. The six output ports of the methanol input pipe 4 supply fuel to each intake port 2 through independent methanol injectors 5. The electronic control system can independently adjust the injection quantity and injection timing according to the real-time operating conditions of each cylinder, such as load and speed, to accurately control the air-fuel ratio of each cylinder, solve the problem of inter-cylinder differences in the traditional manifold mixing mode, and significantly improve fuel economy and emission performance, especially under partial load conditions.

[0050] In summary, the methanol injection device of this invention, through its independent injection design, reduces the contact area and time between methanol and the inner wall of the intake manifold, thereby reducing the risk of corrosion and extending the service life of the intake manifold. Atomized methanol is directly injected into the bottom of the intake manifold, forming a uniform premixed air-fuel mixture, improving combustion efficiency, reducing unburned methanol residue, and decreasing emissions. Each injector is independently controlled, allowing for adjustment of the injection quantity according to the operating conditions of each cylinder, achieving precise control of the air-fuel ratio, optimizing combustion efficiency, and reducing fuel consumption. The electromagnetic coil and spring drive assembly achieves millisecond-level response, adapting to the frequent injection demands of high-horsepower engines operating at high speeds, significantly improving the performance and reliability of high-horsepower methanol engines, and meeting the requirements for clean combustion and efficient operation.

[0051] This embodiment, through the aforementioned structural design and functional synergy, effectively solves the corrosion, air-fuel ratio control, and combustion efficiency problems of traditional methanol engines, meeting the engineering requirements for clean combustion and high reliability.

[0052] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A methanol injection device for a methanol engine, comprising an intake pipe (1), a plurality of intake passages (2) uniformly distributed along the length of the intake pipe (1), and a combustion cylinder (3) installed at the outlet end of each intake passage (2), characterized in that: The device also includes a methanol input pipe (4) installed on the intake pipe (1), the methanol input pipe (4) has multiple outlets, and each outlet is equipped with a methanol injector (5), the injection end of the methanol injector (5) extends to the bottom of the inner cavity of the intake duct (2) to spray atomized methanol.

2. The methanol injection device for a methanol engine according to claim 1, characterized in that, The methanol injector (5) includes a valve body (51) and an ejector tube (52). The rear end of the valve body (51) is installed at the outlet of the methanol input pipe (4) and is connected to it. The front end of the valve body (51) is fixed to the rear end of the ejector tube (52). The front end of the ejector tube (52) has an injection port (53) and extends into the air intake (2). A valve stem (54) is slidably mounted inside the valve body (51). The front end of the valve stem (54) extends slidably into the ejector tube (52) and is in sealing contact with the injection port (53). The rear end of the valve stem (54) is driven by a drive assembly to move along the axial direction of the ejector tube (52).

3. A methanol injection device for a methanol engine according to claim 2, characterized in that, The drive assembly includes an electromagnetic coil (55) and a spring (56) installed inside the rear end of the valve body (51), with the electromagnetic coil (55) facing the rear end of the valve stem (54) and connected to it by the spring (56).

4. A methanol injection device for a methanol engine according to claim 2, characterized in that, The inner side of the nozzle (53) is a concave spherical surface, and a ball head (57) is installed at the front end of the valve stem (54), and the ball head (57) is in contact with the inner spherical surface of the nozzle (53).

5. A methanol injection device for a methanol engine according to claim 2, characterized in that, The intake duct (2) has an installation hole that matches the valve body (51). The valve body (51) is fixedly installed in the installation hole and sealed by a sealing ring (58).

6. A methanol injection device for a methanol engine according to claim 1, characterized in that, A sensor for measuring methanol pressure is installed inside the methanol input pipe (4), and an electrical control harness (6) that is electrically connected to the sensor is installed on the methanol input pipe (4).

7. A methanol injection device for a methanol engine according to claim 1, characterized in that, The methanol input pipe (4) is a double-walled track pipe with a methanol input port (7) connected to the output end of the methanol supply equipment.

8. A methanol injection device for a methanol engine according to claim 1, characterized in that, The outlet of the intake duct (2) is connected to the combustion cylinder (3) through a spiral air passage (8), and the injection end of the methanol injector (5) passes through the intake duct (2) and extends into the opening of the spiral air passage (8).

9. A methanol injection device for a methanol engine according to claim 1, characterized in that, The injection end of the methanol injector (5) extends along the tangential direction of the cylinder head to the inner nose of the spiral air passage (8).

10. A methanol injection device for a methanol engine according to any one of claims 1-9, characterized in that, There are six intake manifolds (2) and they are connected to six combustion cylinders (3) respectively. The methanol input pipe (4) has six output ports, and the six output ports are connected to the bottom of the inner cavity of the intake manifold (2) through a methanol injector (5) respectively, so as to accurately control the air-fuel ratio of each cylinder.

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