A device and method for forced lubrication of a low-carbon fuel injection system
By introducing an air tank, shut-off valve, pressure regulating valve, and oil supply tank into the low-carbon fuel injection system, and utilizing the piston isolation structure of the air chamber and oil chamber to achieve rapid oil pressure build-up, the problem of poor lubricity of low-carbon fuels is solved, and the reliability of the fuel injection system is improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GUANGXI YUCHAI MASCH CO LTD
- Filing Date
- 2024-01-31
- Publication Date
- 2026-08-04
AI Technical Summary
Low-carbon fuels have poor lubricity, leading to reliability issues in fuel injection systems.
Design a forced lubrication device for a low-carbon fuel injection system, including an air tank, a shut-off valve, a pressure regulating valve, and an oil supply tank. The device achieves initial and rapid pressure build-up of the oil through a piston isolation structure between the air chamber and the oil chamber, ensuring that the oil is injected into the air rail.
It improves the lubrication characteristics of the injection system, reduces wear on key components, and enhances the lubricity of low-carbon fuels.
Smart Images
Figure CN117927402B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to low-carbon engines, and more specifically, to a device and control method for forced lubrication of a low-carbon fuel injection system. Background Technology
[0002] Low-carbon fuels, due to their low carbon content and consequently low carbon emissions, have a promising market prospect. Furthermore, low-carbon fuels represent a future direction for internal combustion engine development in order to further reduce carbon emissions. However, low-carbon fuels have poor lubricity, which poses a challenge to the reliability of fuel injection systems. Therefore, we designed a forced lubrication device and control method for low-carbon fuel injection systems. Summary of the Invention
[0003] The technical problem to be solved by the present invention is to address the shortcomings of the prior art by providing a device and control method for forced lubrication of a low-carbon fuel injection system, which improves the lubrication characteristics of the injection system, reduces the wear of key components, and can effectively improve the poor lubricity of low-carbon fuels.
[0004] The present invention discloses a forced lubrication device for a low-carbon fuel injection system, comprising an air tank, a shut-off valve, a pressure regulating valve, and an oil supply tank; the output end of the air tank is connected to the input end of the shut-off valve, and the output end of the shut-off valve is connected to the input end of the pressure regulating valve; the oil supply tank is provided with an air chamber 1, an air chamber 2, an oil chamber 1, and an oil chamber 2; the air chamber 1 is connected to an output end of the pressure regulating valve via a solenoid valve 1, and a piston 1 is movably installed between the air chamber 1 and the oil chamber 1, and an oil filling port is provided on the oil chamber 1; the air chamber 2 is connected to the other output end of the pressure regulating valve via a solenoid valve 2, and a piston 2 is movably installed between the air chamber 2 and the oil chamber 2, a connecting hole is provided between the oil chamber 2 and the oil chamber 1, the oil chamber 1 is connected to the air rail via an oil nozzle, and a one-way valve is provided between the oil chamber 1 and the oil nozzle.
[0005] As a further improvement, the gas tank is connected to the power output of the low-carbon engine via a pressurization device.
[0006] As a further improvement, a stop block is provided in the oil chamber near the oil filling port.
[0007] As a further improvement, a stop block 2 is provided in the second oil cavity near the connecting hole.
[0008] As a further improvement, both air chamber one and air chamber two are provided with exhaust ports, and control valves are installed in the exhaust ports.
[0009] A control method for a device using the aforementioned low-carbon fuel injection system with forced lubrication, the method comprising: The current pressure inside the gas tank is obtained, and it is determined whether the current pressure is greater than or equal to the set pressure threshold. If so, a forced lubrication request is triggered. Otherwise, the gas tank is inflated and its pressure is greater than or equal to the set pressure threshold. Then, it is determined whether the current state of the engine meets the initial conditions for forced lubrication. If the initial conditions for forced lubrication are met, the shut-off valve, pressure regulating valve, and solenoid valve one are opened to introduce pressurized gas into air chamber one, so that piston one pushes the oil in oil chamber one to flow into oil chamber two, so as to initially build up pressure in the oil chamber. After the initial pressure build-up is completed, solenoid valve two is opened to introduce pressurized gas into air chamber two, so that piston two pushes the oil in oil chamber two to quickly build up pressure in oil chamber two, so that the oil pressure in oil chamber two is greater than the opening pressure of the one-way valve. The oil in oil chamber two is then sprayed into the air rail through the oil nozzle. At the same time, the opening time of solenoid valve two is controlled by the oil injection model.
[0010] As a further improvement, the jetting model is as follows: ; In the formula, Q is the amount of oil injected into the air rail; Q1 is the initial amount of oil added to the oil chamber; ε is the correction coefficient for the amount of oil in the oil chamber; and t is the working time of the second air chamber.
[0011] As a further improvement, after the oil injection is completed, the first solenoid valve is disconnected, and the air in the first air chamber is discharged; after the first solenoid valve is disconnected for a set time, the second solenoid valve is disconnected, and the air in the first air chamber is discharged.
[0012] As a further improvement, a forced lubrication cycle is set based on the engine's operating time; when the forced lubrication cycle is reached, a forced lubrication request is triggered.
[0013] With further improvements, the output pressure of the pressure regulating valve is 0.3±0.05MPa.
[0014] Beneficial effects The advantages of this invention are as follows: The injection system incorporates components such as a shut-off valve, a pressure regulating valve, and an oil supply tank. The oil supply tank contains two air chambers and two oil chambers. Air chamber one and oil chamber one are separated by a piston. Inflating air chamber one initially pressurizes the oil in the oil chamber to meet the pressure requirements for injection. Air chamber two and oil chamber two are separated by a piston. Inflating air chamber two rapidly builds up pressure in the oil chamber to reach the opening pressure of the one-way valve, thus achieving immediate fuel injection for lubrication of the injector. This improves the lubrication characteristics of the injection system, reduces wear on key components, and effectively addresses the poor lubricity of low-carbon fuels. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the forced lubrication device for the low-carbon fuel injection system of the present invention. Figure 2 This is a schematic diagram of the internal structure of the oil supply tank of the present invention.
[0016] Wherein: 1-oil supply box, 2-air chamber one, 3-piston one, 4-oil filler port, 5-oil chamber one, 6-oil chamber two, 7-air chamber two, 8-piston two, 9-stop block two, 10-one-way valve, 11-oil nozzle, 12-stop block one, 13-connecting hole. Detailed Implementation
[0017] The present invention will be further described below with reference to embodiments, but this does not constitute any limitation on the present invention. Any limited modifications made by any person within the scope of the claims of the present invention are still within the scope of the claims of the present invention. See Figures 1-2 This invention discloses a forced lubrication device for a low-carbon fuel injection system, comprising an air tank, a shut-off valve, a pressure regulating valve, and an oil supply tank 1. The output end of the air tank is connected to the input end of the shut-off valve, and the output end of the shut-off valve is connected to the input end of the pressure regulating valve. The oil supply tank 1 contains an air chamber 2, an air chamber 7, an oil chamber 5, and an oil chamber 6. Air chamber 2 is connected to the output end of the pressure regulating valve via a solenoid valve. A piston 3 is movably mounted between air chamber 2 and oil chamber 5, and an oil filler port 4 is provided on oil chamber 5. Air chamber 7 is connected to the other output end of the pressure regulating valve via a solenoid valve. A piston 8 is movably mounted between air chamber 7 and oil chamber 6. A connecting hole 13 is provided between oil chamber 6 and oil chamber 5. Oil chamber 5 is connected to the air rail via an oil nozzle 11, and a one-way valve 10 is provided between oil chamber 5 and the oil nozzle 11. The air rail is also connected to the fuel tank and the low-carbon engine.
[0018] The system comprises two chambers: an air chamber (2) and an oil chamber (5), separated by a piston (3). Inflating the air chamber (2) allows oil from the oil chamber (5) to be pumped through the connecting hole (13) into the oil chamber (6), initially pressurizing the oil to meet the injection pressure requirements. An air chamber (7) and an oil chamber (6) are separated by a piston (8). Inflating the air chamber (7) rapidly builds pressure in the oil chamber to the opening pressure of the one-way valve (10), enabling immediate fuel injection for lubrication of the injector. This improves the lubrication characteristics of the injection system, reduces wear on key components, and effectively addresses the poor lubricity of low-carbon fuels.
[0019] In this embodiment, the gas tank is connected to the power output of the low-carbon engine via a pressurization device. That is, the pressurization device uses the engine's output as power to operate and thus inflate the gas tank. The pressurization device is a commercially available pressurization device, such as an air compressor.
[0020] A stop block 12 is provided in oil chamber 5 near the oil filling port 4 to limit the movement of piston 3 and prevent it from moving too far. A stop block 9 is provided in oil chamber 6 near the connecting hole 13 to limit the movement of piston 8 and prevent it from moving too far.
[0021] In addition, both air chamber 2 and air chamber 7 in this embodiment are provided with exhaust ports, and control valves are installed in the exhaust ports to discharge the gas in the air chambers after the oil injection is completed.
[0022] A control method for forced lubrication of a low-carbon fuel injection system is provided. This method is based on the aforementioned forced lubrication device for a low-carbon fuel injection system, and the specific implementation method is as follows.
[0023] In a low-carbon fuel engine, fuel enters the air rail from the fuel tank via low-pressure management. Under the command of the ECU, it is injected into the cylinders in an orderly manner for combustion and output of effective power. The ECU tracks the engine's operating time to determine its cumulative operating time. A low-carbon fuel engine typically operates for 200-300 hours; specifically, this embodiment uses an operating time exceeding 200 hours as an example, at which point lubrication is triggered.
[0024] After receiving a lubrication request, the ECU determines whether the current pressure in the gas tank meets the requirements. If it does, for example, if the current pressure is above 1.0 MPa, a forced lubrication request is triggered. If the pressure requirement is not met, the ECU enters the inflation phase until the pressure in the gas tank reaches above 1.0 MPa before triggering the forced lubrication request again. After triggering the forced lubrication request, the ECU determines whether the current engine state meets the initial conditions for forced lubrication, such as engine speed, air rail pressure, fuel injection quantity, etc., and whether they meet the initial value settings. If the initial conditions for forced lubrication are met, the ECU controls the lubrication device's shut-off valve to open and adjusts the output pressure of the pressure regulating valve to 0.3 ± 0.05 MPa through the pressure regulating valve. Then, the solenoid valve one of the right-side air chamber one 2 in the oil supply tank 1 is opened, allowing gas to enter air chamber one 2, while simultaneously pushing piston one 3 to move to the left. At this time, the oil in oil chamber one 5, under the push of piston one 3, initially builds up pressure and enters the left-side oil chamber two 6 through the connecting hole 13 between oil chamber one 5 and oil chamber two 6.
[0025] Approximately 3-5 seconds later, the solenoid valve 2 of the left-side air chamber 2 7 opens, allowing gas to enter. Driven by the gas pressure, the oil in oil chamber 2 6 moves upward. At this time, the oil in both oil chambers, pushed by the pistons on both sides, rapidly builds up oil pressure. When the oil pressure exceeds the opening pressure of the one-way valve 10, the oil is injected into the air rail through the oil nozzle 11. Driven by the fuel, the oil and fuel mix thoroughly and enter the injector. This increased fuel-oil lubrication effectively reduces injector wear.
[0026] During the rapid build-up of oil pressure, the pistons in both chambers move simultaneously, and the amount of piston movement determines the amount of oil injected. This piston movement is further determined by the opening time of the solenoid valve. Therefore, this embodiment establishes an oil injection model based on the solenoid valve's opening time. This injection model can be expressed as: .
[0027] Where Q is the amount of oil injected into the air rail; Q1 is the initial amount of oil added to the oil chamber. Initially, there is no oil in oil chamber one, and this amount refers to the amount of oil in oil chamber two; ε is the correction coefficient for the amount of oil in the oil chamber; t is the working time of air chamber two, i.e., the working time of solenoid valve two. The working time of air chamber one is the working time of air chamber two plus an advance, such as 3-5s as mentioned above.
[0028] By establishing the relationship between the opening time of the solenoid valve and the amount of oil injected, precise control of oil injection lubrication is achieved. At the same time, the correction coefficient ε for the reduction of oil in the oil chamber is taken into account, ensuring that the injection amount meets the single requirement each time and that the injection amount will not decrease due to the reduction of oil in the oil chamber.
[0029] After injection is complete, solenoid valve one is first disconnected, and the air in air chamber one 2 is discharged. However, air chamber two 7 is still under pressure at this time. Therefore, the oil in oil chamber one 5 will quickly flow into oil chamber two 6. About 1-2 seconds after solenoid valve one is disconnected, solenoid valve two is disconnected, and the air in air chamber one 2 is discharged. Piston two 8 moves and resets under the action of gravity.
[0030] After one forced lubrication cycle is completed, the forced lubrication cycle is reset to zero, and the working time is recalculated. When the accumulated time reaches 200 hours again, a forced lubrication request is triggered again. This process is repeated to meet the lubrication requirements of the injection system.
[0031] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention, and these will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.
Claims
1. A device for forced lubrication of a low-carbon fuel injection system, characterized in that, It includes an air tank, a shut-off valve, a pressure regulating valve, and an oil supply tank (1); the output end of the air tank is connected to the input end of the shut-off valve, and the output end of the shut-off valve is connected to the input end of the pressure regulating valve; the oil supply tank (1) is provided with an air chamber one (2), an air chamber two (7), an oil chamber one (5), and an oil chamber two (6); the air chamber one (2) is connected to the output end of the pressure regulating valve through a solenoid valve one, and a piston one (3) is movably installed between the air chamber one (2) and the oil chamber one (5). The first oil chamber (5) is provided with an oil filling port (4); the second air chamber (7) is connected to the other output end of the pressure regulating valve through the second solenoid valve; the second piston (8) is movably installed between the second air chamber (7) and the second oil chamber (6); the second oil chamber (6) is provided with a connecting hole (13) between the first oil chamber (5); the first oil chamber (5) is connected to the air rail through the oil nozzle (11); and the first oil chamber (5) is provided with a one-way valve (10) between the oil nozzle (11). The control method for the forced lubrication device of the low-carbon fuel injection system is as follows: The current pressure inside the gas tank is obtained, and it is determined whether the current pressure is greater than or equal to the set pressure threshold. If so, a forced lubrication request is triggered. Otherwise, the gas tank is inflated and its pressure is greater than or equal to the set pressure threshold. Then, it is determined whether the current state of the engine meets the initial conditions for forced lubrication. If the initial conditions for forced lubrication are met, the shut-off valve, pressure regulating valve and solenoid valve 1 are opened to send pressurized gas into air chamber 1 (2) so that piston 1 (3) pushes the oil in oil chamber 1 (5) to oil chamber 2 (6) to initially build up pressure in the oil chamber. After the initial pressure build-up is completed, the second solenoid valve is opened to introduce pressurized gas into the second air chamber (7), so that the second piston (8) pushes the oil in the second oil chamber (6) to quickly build up pressure in the second oil chamber (6), so that the oil pressure in the second oil chamber (6) is greater than the opening pressure of the one-way valve (10). The oil in the second oil chamber (6) is sprayed into the air rail through the oil nozzle (11); at the same time, the opening time of the second solenoid valve is controlled by the oil injection model. The jetting model is, ； In the formula, Q is the amount of oil injected into the air rail; Q1 is the initial amount of oil added to the oil chamber; ε is the correction coefficient for the amount of oil in the oil chamber; and t is the working time of the second air chamber.
2. The device for forced lubrication of a low-carbon fuel injection system according to claim 1, characterized in that, The gas tank is connected to the power output end of the low-carbon engine via a pressurization device.
3. The device for forced lubrication of a low-carbon fuel injection system according to claim 1, characterized in that, A stop block (12) is provided in the oil chamber (5) near the oil filling port (4).
4. The device for forced lubrication of a low-carbon fuel injection system according to claim 1, characterized in that, The oil cavity 2 (6) is provided with a stop block 2 (9) near the connecting hole (13).
5. The device for forced lubrication of a low-carbon fuel injection system according to claim 1, characterized in that, Both air chamber one (2) and air chamber two (7) are provided with exhaust ports, and control valves are installed in the exhaust ports.
6. The device for forced lubrication of a low-carbon fuel injection system according to claim 1, characterized in that, After the oil injection is completed, the first solenoid valve is disconnected, and the air in the first air chamber (2) is discharged. After the first solenoid valve is disconnected for a set time, the second solenoid valve is disconnected, and the air in the first air chamber (2) is discharged.
7. The device for forced lubrication of a low-carbon fuel injection system according to claim 1, characterized in that, A forced lubrication cycle is set based on the engine's operating time; when the forced lubrication cycle is reached, a forced lubrication request is triggered.
8. The device for forced lubrication of a low-carbon fuel injection system according to claim 1, characterized in that, The output pressure of the pressure regulating valve is 0.3±0.05MPa.