Methanol pump and methanol fuel temperature control system

Abstract

The invention discloses a methanol pump and a methanol fuel temperature control system, and relates to the technical field of fuel pumps, the methanol pump comprises a shell assembly, a pump body, a driving motor and a controller; a liquid inlet and a liquid outlet are formed in the two ends of the shell assembly respectively. The pump body is arranged in the shell assembly and is close to the liquid inlet, and the pump body comprises a cycloid gear and an inner gear which are eccentrically meshed; the driving motor is arranged in the shell assembly, and an output shaft of the driving motor is connected with the cycloid gear; the controller is arranged on one side of the shell assembly and electrically connected with the driving motor. According to the technical scheme, the working efficiency and reliability of the methanol pump can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel pumps, and particularly to a methanol pump and a methanol fuel temperature control system. Background Art

[0002] In the modern energy system, methanol is widely regarded as a new type of clean energy due to its clean combustion, renewable nature, and high energy density. In the methanol vehicle-related industry, traditional gear pumps are usually selected for methanol pumps. Such pumps achieve fluid transportation through the precise meshing of two or more gears. However, gear pumps have some inherent defects during operation: the friction and collision between gears and with the inner wall of the pump body generate mechanical noise, and due to the certain gap between gears, internal leakage is likely to occur. These problems not only affect the working efficiency and reliability of the methanol pump but may also have an adverse impact on its long-term service life. Summary of the Invention

[0003] The main object of the present invention is to propose a methanol pump and a methanol fuel temperature control system, aiming to improve the working efficiency and reliability of the methanol pump.

[0004] To achieve the above object, the methanol pump proposed by the present invention includes:

[0005] A housing assembly, with a liquid inlet and a liquid outlet respectively provided at both ends of the housing assembly;

[0006] A pump body, which is arranged inside the housing assembly and close to the liquid inlet. The pump body includes a cycloidal gear and an internal gear that are eccentrically meshed;

[0007] A driving motor, which is arranged inside the housing assembly, and the output shaft of the driving motor is connected to the cycloidal gear; and

[0008] A controller, which is arranged on one side of the housing assembly, and the controller is electrically connected to the driving motor.

[0009] In one embodiment, the housing assembly includes an outer shell, a front end cover and a rear end cover respectively arranged at both ends of the outer shell. The liquid inlet is provided on the front end cover, and the liquid outlet is provided on the rear end cover.

[0010] In one embodiment, the methanol pump further includes two sealing rings, and the two sealing rings are respectively sleeved on the front end cover and the rear end cover and are hermetically attached to the inner wall of the outer shell.

[0011] In one embodiment, the methanol pump further includes a limiting plate, which is arranged inside the outer shell and encloses a receiving cavity with the front end cover. The pump body is arranged in the receiving cavity, and the output shaft of the driving motor passes through the limiting plate and is connected to the cycloidal gear.

[0012] In one embodiment, the methanol pump further includes a bearing, which is disposed within the housing assembly and on the side of the pump body facing away from the drive motor;

[0013] The output shaft passes through the cycloidal gear and is connected to the bearing.

[0014] In one embodiment, the bearing is made of polyetheretherketone.

[0015] In one embodiment, the methanol pump further includes a positioning plate, which is disposed within the housing assembly and is close to the liquid outlet. The positioning plate is formed with a positioning groove, and a bearing is provided in the positioning groove;

[0016] One end of the output shaft away from the pump body is connected to the bearing.

[0017] In one embodiment, a protective housing is provided on the outer periphery of the drive motor, and the protective housing is formed with a plurality of grooves, and the plurality of grooves are distributed in a circular array.

[0018] In one embodiment, the drive motor is a brushless motor.

[0019] The present invention also provides a methanol fuel temperature control system, which includes a fuel tank, a supply pipeline, and an engine connected in sequence; a methanol pump, an electric heater, and a heat exchanger as described above are sequentially provided on the supply pipeline;

[0020] It further includes a recovery pipeline, which connects the supply pipeline and the fuel tank. A radiator, an expansion tank, a thermostat, and a water tank are sequentially provided on the recovery pipeline. The recovery pipeline is heat exchange coupled to the supply pipeline through the heat exchanger, and the thermostat is used to control the flow direction of the waste heat of the engine.

[0021] In the technical solution of the present invention, through the special structure of the eccentrically meshing cycloidal gear and internal gear, the tooth clearance and meshing mode are optimized, effectively reducing the risk of internal leakage; and the drive motor is disposed within the housing assembly and directly connected to the cycloidal gear, ensuring the high efficiency and stability of power transmission, and at the same time effectively shortening the axial length of the methanol pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0023] Figure 1 Cross-sectional view of an embodiment of the methanol pump provided by the present invention;

[0024] Figure 2 Cross-sectional view of another embodiment of the methanol pump provided by the present invention;

[0025] Figure 3 Structural schematic diagram of an embodiment of the methanol fuel temperature control system provided by the present invention.

[0026] Explanation of the reference numerals in the drawings:

[0027] 100, methanol pump; 1, outer shell; 2, front end cover; 21, liquid inlet; 3, rear end cover; 31, liquid outlet; 4, pump body; 41, cycloidal gear; 42, internal gear; 5, drive motor; 6, controller; 7, sealing ring; 8, limiting plate; 9, bearing; 10, positioning plate;

[0028] 200, fuel tank; 300, engine; 400, electric heater; 500, heat exchanger; 600, radiator; 700, expansion tank; 800, thermostat; 900, water tank.

[0029] The realization, functional features and advantages of the object of the present invention will be further described in conjunction with the embodiments with reference to the drawings. Specific embodiments

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work shall fall within the protection scope of the present invention.

[0031] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present invention, the directional indications are only used to explain the relative position relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0032] In addition, if the embodiments of the present invention involve descriptions such as "first" and "second", the descriptions of "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, if "and / or" or "and / or" appears throughout the text, its meaning includes three parallel scenarios. Taking "A and / or B" as an example, it includes Scenario A, or Scenario B, or the scenario where both A and B are satisfied simultaneously. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0033] The present invention provides a methanol pump 100.

[0034] Please refer to Figure 1 and Figure 2 , in an embodiment of the present invention, the methanol pump 100 includes a housing assembly, a pump body 4, a drive motor 5, and a controller 6; liquid inlets 21 and outlets 31 are respectively provided at both ends of the housing assembly; the pump body 4 is disposed within the housing assembly and is disposed near the liquid inlet 21. The pump body 4 includes a cycloidal gear 41 and an internal gear 42 that are eccentrically meshed; the drive motor 5 is disposed within the housing assembly, and the output shaft of the drive motor 5 is connected to the cycloidal gear 41; the controller 6 is disposed on one side of the housing assembly, and the controller 6 and the drive motor 5 are electrically connected.

[0035] Among them, the cycloidal gear 41 serves as the inner rotor and the internal gear ring serves as the outer rotor. The two are eccentrically meshed to form a dynamically changing sealed chamber. When the drive motor 5 drives the inner rotor to rotate, the chamber volume between the meshing teeth gradually increases on the suction side to form a negative pressure, sucking methanol from the inlet; as the rotor rotates, the chamber moves along the pump body 4 towards the discharge side and gradually reduces in volume, forming a pressurization process, and finally discharging methanol at high pressure through the outlet. Moreover, the cycloidal gear 41 and the internal gear ring are made of bidirectional sintered silicon carbide (SSiC) or have a DLC coating on the surface, which can withstand long-term immersion in methanol and corrosion by acidic impurities.

[0036] The liquid inlet 21 adopts a tapered Venturi structure to reduce inlet turbulence and the risk of cavitation; the outlet 31 adopts a spiral diffuser design to convert kinetic energy into static pressure and improve the head efficiency.

[0037] The controller 6 is directly connected to the drive motor 5 through a sealed interface, which can ensure a tight and reliable electrical connection between the controller 6 and the drive motor 5, isolate the risk of methanol liquid, water vapor, or corrosive gas invading the interior of the controller 6, and avoid circuit short circuits or component corrosion.

[0038] In the technical solution of the present invention, through the special structure of the cycloidal gear 41 and the internal gear 42 with eccentric meshing, the tooth clearance and meshing mode are optimized, effectively reducing the risk of internal leakage; and the driving motor 5 is arranged in the housing assembly and directly connected to the cycloidal gear 41, ensuring the high efficiency and stability of power transmission, and at the same time effectively shortening the axial length of the methanol pump 100.

[0039] Specifically, in an embodiment of the present invention, please refer to Figure 1 , the housing assembly includes a housing 1, a front end cover 2 and a rear end cover 3 respectively arranged at both ends of the housing 1. The liquid inlet 21 is arranged on the front end cover 2, and the liquid outlet 31 is arranged on the rear end cover 3. In this way, the liquid inlet 21 and the liquid outlet 31 are respectively arranged at both ends of the housing. After the fluid enters from the front end of the pump body 4, it flows axially through the meshing area of the cycloidal gear 41 and the internal gear 42, and finally discharges from the rear end, forming a unidirectional linear flow path. And the front end cover 2 and the rear end cover 3 are assembled with the housing 1 as independent components, and can be optimized and designed respectively according to the sealing requirements of the inlet and outlet.

[0040] Further, in an embodiment of the present invention, please refer to Figure 1 , the methanol pump 100 further includes two sealing rings 7. The two sealing rings 7 are respectively sleeved on the front end cover 2 and the rear end cover 3, and are hermetically attached to the inner wall of the housing 1. By setting the sealing ring 7, when the front end cover 2 and the rear end cover 3 are installed on the housing 1, the sealing ring 7 is compressed between the end cover and the inner wall of the housing 1 to form a tight sealing surface. This sealing method can effectively prevent the methanol liquid from leaking from the gap between the end cover and the housing 1, ensure the reliable sealing performance of the methanol pump 100 during operation, and avoid the loss of methanol and environmental pollution. And the sealing ring 7 has a certain elasticity, can adapt to the slight deformation of the components, and always maintains a tight fit with the inner wall of the housing 1. Even under the working conditions with large temperature changes, it can maintain a good sealing effect, prevent methanol leakage, and improve the stability and reliability of the methanol pump 100 under different environmental conditions. In addition, both the front end cover 2 and the rear end cover 3 are provided with annular grooves for installing the sealing ring 7.

[0041] In this embodiment, the material of the sealing ring 7 is perfluoroether rubber (FFKM). Perfluoroether rubber can resist the erosion of strong acids and alkalis, will not decompose, rupture or degrade in performance, ensuring that the sealing ring 7 maintains good sealing performance during long-term use. And during the operation of the methanol pump 100, especially during high-load or long-time operation, the internal temperature may rise. Perfluoroether rubber can work stably at a temperature up to 200 °C or even higher for a long time, and will not accelerate aging or lose elasticity due to high temperature, thus ensuring that the sealing ring 7 can still effectively prevent methanol leakage in a high-temperature environment and maintain the normal operation of the methanol pump 100.

[0042] Further, in an embodiment of the present invention, please refer to Figure 1, the methanol pump 100 further includes a limiting plate 8. The limiting plate 8 is disposed inside the housing 1 and encloses a receiving cavity with the front end cover 2. The pump body 4 is disposed in the receiving cavity, and the output shaft of the driving motor 5 passes through the limiting plate 8 and is connected to the cycloid gear 41. The receiving cavity formed by the limiting plate 8 and the front end cover 2 provides an accurate installation position for the pump body 4. The pump body 4 is stable in position within the cavity, avoiding excessive axial or radial movement. This stable positional relationship ensures the accuracy of the eccentric meshing between the cycloid gear 41 and the internal gear ring. When the driving motor 5 drives the cycloid gear 41 to rotate, the two can maintain a stable meshing state, improving the working efficiency of the methanol pump 100 and ensuring the continuity and stability of methanol delivery.

[0043] To improve stability, in an embodiment of the present invention, please refer to Figure 1 , the methanol pump 100 further includes a bearing 9. The bearing 9 is disposed inside the housing assembly and is located on the side of the pump body 4 facing away from the driving motor 5; the output shaft passes through the cycloid gear 41 and is connected to the bearing 9. Specifically, the bearing 9 is disposed on the front end cover 2. By adding the bearing 9, the output shaft passes through the cycloid gear 41 and is connected to the bearing 9 to form a double-sided support structure, significantly enhancing the rigidity and stability of the transmission system: the two bearings 9 cooperate to share the radial load, effectively suppressing the deflection and vibration of the output shaft during high-speed rotation or sudden load changes, ensuring the meshing accuracy between the cycloid gear 41 and the internal gear 42, reducing the tooth surface wear and seal cavity clearance fluctuations caused by shaft deformation, thereby reducing the risk of internal leakage and extending the gear life; at the same time, the damping effect of the bearing 9 absorbs the gear meshing impact energy, further reducing mechanical noise and enhancing the running stability and reliability of the methanol pump 100 under complex working conditions, especially suitable for methanol direct injection systems with high rotational speed and high pressure requirements, providing key support for efficient and stable methanol fuel delivery.

[0044] In this embodiment, the material of the bearing 9 is polyether ether ketone (PEEK). Polyether ether ketone has excellent tolerance to organic solvents such as methanol, ensuring the cleanliness and long-term sealing performance of the pump cavity. And the inherent self-lubricating property of polyether ether ketone reduces the frictional loss between the bearing 9 and the output shaft, reduces the running resistance, improves the energy efficiency of the driving motor 5, and at the same time avoids the risk of contamination of methanol purity caused by the introduction of additional lubricants.

[0045] To further improve stability, in an embodiment of the present invention, please refer to Figure 1 , the methanol pump 100 further includes a positioning plate 10. The positioning plate 10 is disposed inside the housing assembly and is disposed near the liquid outlet 31. The positioning plate 10 is formed with a positioning groove, and the bearing 9 is disposed in the positioning groove; the end of the output shaft away from the pump body 4 is connected to the bearing 9. Thus, both ends of the output shaft are connected to a bearing 9, and the two bearings 9 can provide positioning and support for both ends of the output shaft, ensuring the coaxiality between the output shaft and the pump body 4. This helps to maintain the precise meshing between the cycloid gear 41 and the internal gear ring, improving the working efficiency and reliability of the methanol pump 100.

[0046] Further, in an embodiment of the present invention, a protective housing is provided on the outer periphery of the drive motor 5. The protective housing is formed with a plurality of grooves, and the plurality of grooves are distributed in an annular array. The grooves can allow methanol liquid to pass through, so that the methanol liquid can directly absorb the heat generated by the drive motor 5, avoiding the efficiency reduction or the risk of permanent magnet demagnetization caused by overheating of the motor. In addition, the heat generated during the operation of the controller 6 can also be transferred to the housing assembly and then absorbed by the methanol liquid to achieve temperature control of the controller 6. Among them, the material of the protective housing is 316L stainless steel, which has both methanol corrosion resistance and mechanical strength.

[0047] Specifically, in an embodiment of the present invention, the drive motor 5 is a brushless motor. The brushless motor eliminates the frictional loss between the carbon brush and the commutator in the traditional brushed motor, reduces the loss during the energy conversion process, thereby improving the overall working efficiency of the methanol pump 100, achieving energy-saving operation, and reducing the energy consumption cost. And the brushless motor can be used in conjunction with an advanced electronic control system, enabling more precise speed control and torque adjustment. The flow rate and pressure of methanol can be quickly and accurately adjusted according to actual needs, improving the control accuracy and response speed of the system, and better meeting the usage requirements under different working conditions.

[0048] Please refer to Figure 3 , the present invention also proposes a methanol fuel temperature control system, which includes a fuel tank 200, a supply pipeline, and an engine 300 connected in sequence; a methanol pump 100, an electric heater 400, and a heat exchanger 500 are sequentially arranged on the supply pipeline; it further includes a recovery pipeline, the recovery pipeline connects the supply pipeline and the fuel tank 200, and a radiator 600, an expansion tank 700, a thermostat 800, and a water tank 900 are sequentially arranged on the recovery pipeline. The recovery pipeline is heat exchange coupled with the supply pipeline through the heat exchanger 500, and the thermostat 800 is used to control the flow direction of the waste heat of the engine 300. The waste heat of the engine 300 can be directed to the heat exchanger 500 through the thermostat 800, thereby preheating the liquid methanol in the supply pipeline. After preheating, the viscosity of methanol is significantly reduced, its fluidity is enhanced, the conveying load of the methanol pump 100 is greatly reduced, its power consumption is reduced, and the fuel atomization effect is improved, thereby improving the combustion efficiency and reducing pollutant emissions during the cold start stage. Among them, for methanol at different temperatures, corresponding control methods are adopted:

[0049] Low-temperature start-up stage (-30°C to 10°C): The main goal of this stage is to quickly heat up methanol to the safe flow temperature to prevent solidification and damage to the pump body 4. The methanol pump 100 starts a small-flow circulation (0.2 - 0.5 m

[0050] / h), the electric heater 400 heats methanol with a stepped power load (25% → 50% → 100%), and the target temperature is 10°C; the thermostat 800 closes the waste heat recovery circuit, and controls the waste heat of the engine 300 to be directly discharged through the radiator 600. That is, methanol flows from the fuel tank 200 through the methanol pump 100, then is heated by the electric heater 400, and finally enters the engine 300; at the same time, the waste heat of the engine 300 is directly discharged through the heat dissipation pipeline under the control of the thermostat 800.

[0051] The small flow cycle can reduce the pumping resistance. The stepped power load of the electric heater 400 can avoid thermal shock and ensure the heating efficiency. The direct discharge of the waste heat of the engine 300 through the radiator 600 can avoid the risk of freezing and cracking caused by low-temperature methanol entering the heat exchanger 500.

[0052] Medium-temperature operation stage (10°C to 60°C): The thermostat 800 adjusts the three-way valve to direct 30%-70% of the waste heat to the heat exchanger 500. At this time, the waste heat of the engine 300 can transfer heat through the recovery pipeline and the heat exchanger 500 to preheat the liquid methanol in the supply pipeline, and the flow directions in the recovery pipeline and the supply pipeline are opposite, which can improve the heat exchange efficiency.

[0053] When the waste heat of the engine 300 is insufficient or the methanol demand suddenly increases, heat can be supplemented through the electric heater 400; when the waste heat is excessive, part of the waste heat flows to the radiator 600 for direct discharge to maintain the coolant temperature of the engine 300 < 90°C.

[0054] High-temperature stage (60°C to 80°C): Turn off the electric heater 400, increase the methanol flow rate to 4 - 5 m3 / h, absorb sensible heat and latent heat through the heat exchanger 500, and relieve pressure through the expansion tank 700 to avoid the accumulation of gaseous methanol.

[0055] If the methanol temperature > 80°C, start the forced air cooling of the radiator 600, and at the same time, the methanol pump 100 reduces its speed (the flow rate decreases by 30%); a condensation reflux device is provided in the fuel tank 200, and the vaporized methanol is re-liquefied and returned to the cycle.

[0056] Pay attention to system safety and rapid recovery at extreme temperatures (methanol temperature < -30°C or methanol temperature > 100°C):

[0057] At ultra-low temperatures, the electric heater 400 operates at full power, and the methanol pump 100 starts and stops intermittently (runs for 30 s / pauses for 10 s) to prevent dry running; the heat exchanger 500 is emptied and filled with antifreeze, and the water tank 900 assists in circulating and heating up.

[0058] At extremely high temperatures, the waste heat input path to the heat exchanger 500 is cut off, and the waste heat flows into the radiator 600. The radiator 600 runs at full speed, and the thermostat 800 switches to the emergency cooling circuit; the pressure relief valve of the expansion tank 700 is fully opened, and the methanol pump 100 switches to the small circulation mode (flow rate 0.1m3 / h).

[0059] Through the methanol fuel temperature control system, a dynamic adjustment mechanism is designed to link waste heat recovery with the methanol pump 100, which not only improves the low-temperature starting performance, but also maintains the temperature of the methanol delivery pipeline stable, avoiding the decrease in pumping efficiency or air blockage caused by temperature fluctuations.

[0060] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A methanol pump, characterized in that, Comprising: A housing assembly, with a liquid inlet and a liquid outlet respectively provided at both ends of the housing assembly; A pump body, which is arranged inside the housing assembly and is close to the liquid inlet. The pump body includes a cycloidal gear and an internal gear that are eccentrically meshed; A driving motor, which is arranged inside the housing assembly. The output shaft of the driving motor is connected to the cycloidal gear; And A controller, which is arranged on one side of the housing assembly. The controller is electrically connected to the driving motor.

2. The methanol pump according to claim 1, characterized in that, The housing assembly includes a housing and a front end cover and a rear end cover respectively arranged at both ends of the housing. The liquid inlet is provided on the front end cover, and the liquid outlet is provided on the rear end cover.

3. The methanol pump according to claim 2, wherein The methanol pump further includes two sealing rings, which are respectively sleeved on the front end cover and the rear end cover and are hermetically attached to the inner wall of the housing.

4. The methanol pump according to claim 2, wherein, The methanol pump further includes a limiting plate, which is arranged inside the housing and encloses a receiving cavity with the front end cover. The pump body is arranged inside the receiving cavity, and the output shaft of the driving motor passes through the limiting plate and is connected to the cycloidal gear.

5. The methanol pump according to claim 1, characterized in that, The methanol pump further includes a bearing, which is arranged inside the housing assembly and is located on the side of the pump body facing away from the driving motor; The output shaft passes through the cycloidal gear and is connected to the bearing.

6. The methanol pump according to claim 5, characterized in that, The material of the bearing is polyetheretherketone.

7. The methanol pump according to claim 1, characterized in that, The methanol pump further includes a positioning plate, which is arranged inside the housing assembly and is close to the liquid outlet. The positioning plate is formed with a positioning groove, and a bearing is arranged inside the positioning groove; One end of the output shaft away from the pump body is connected to the bearing.

8. The methanol pump according to claim 1, characterized in that, A protective shell is arranged on the outer periphery of the driving motor, and the protective shell is formed with a plurality of grooves, and the plurality of grooves are distributed in an annular array.

9. The methanol pump according to claim 1, characterized in that, The driving motor is a brushless motor.

10. A methanol fuel temperature control system, characterized in that, Including a fuel tank, a supply pipeline and an engine connected in sequence; on the supply pipeline, there are successively arranged the methanol pump, an electric heater and a heat exchanger as described in any one of claims 1 to 9; It further includes a recovery pipeline, which connects the supply pipeline and the fuel tank. The recovery pipeline is successively provided with a radiator, an expansion tank, a thermostat and a water tank. The recovery pipeline is heat exchange coupled with the supply pipeline through the heat exchanger, and the thermostat is used to control the flow direction of the waste heat of the engine.

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