Oil pump for automobile engine and preparation process

Abstract

The invention discloses an engine oil pump for an automobile engine, which is characterized by comprising a pump body which forms a closed space for engine oil to flow together with a pump cover; the transmission shaft penetrates through the pump body and the rotor, is connected with an engine and is used for driving the rotor and the blades to work; the rotor is sleeved on the transmission shaft; the blades are mounted in the grooves of the rotor and can slide in the grooves; the swing ring surrounds the outer sides of the rotor and the blades; the filter assembly is installed on the pump cover, located at the oil inlet of the oil pump and used for filtering impurities in the oil. The adjusting spring is arranged in the pump body, connected with the swing ring and used for controlling the position of the swing ring. The method has the beneficial effects that working conditions are accurately adapted, and energy consumption is reduced; the structural design is optimized, and stable operation is guaranteed; mold manufacturing is innovative, and precision quality is improved; the rotor is finely processed, and dimensional precision is ensured; assembly tracing is comprehensive, and troubleshooting is facilitated; performance detection is strict, and product reliability is guaranteed.

Description

Technical Field

[0001] The present invention relates to an oil pump, and more particularly to an oil pump for an automotive engine and a preparation process therefor. Background Art

[0002] In the current booming automotive industry, environmental protection and energy conservation have become a global consensus. This trend has imposed more stringent requirements on automotive engine technology. With the increasingly strict national fuel consumption regulations, automotive engines are continuously evolving towards higher speed and more energy-efficient directions. Reducing engine fuel consumption has become a key technical problem that needs to be solved urgently in the automotive manufacturing field. In this context, variable displacement oil pumps have become the focus of research by major automakers due to their significant advantages of accurately regulating the oil flow according to the engine working conditions, reducing the driving power of the oil pump, and thus reducing the engine fuel consumption. Among them, the development of the EB08 variable displacement oil pump has attracted much attention;

[0003] Traditional oil pumps have the following defects when facing the complex working conditions of modern engines:

[0004] 1) Their layouts often fail to meet the requirements of compactness, resulting in low space utilization efficiency in the engine compartment. The matching precision between the rotors and vanes of some traditional oil pumps is insufficient, affecting the oil pumping efficiency, and the wear is aggravated easily during high-load operation, shortening the service life of the oil pump;

[0005] 2) It is difficult for traditional oil pumps to achieve precise control of the oil flow and pressure. Under low-load working conditions of the engine, the oil pump continuously outputs a large amount of oil, which not only causes energy waste, but also increases the operating resistance of the engine, leading to an increase in fuel consumption; while under high-load working conditions, there may be insufficient oil supply, unable to meet the lubrication requirements of each component of the engine, affecting the engine performance, and even causing failures;

[0006] 3) The flaw detection and inspection link in the production process of traditional oil pumps is not perfect enough. The detection means for internal defects of key components such as rotors are limited, and it is difficult to ensure the reliability of product quality. Moreover, there is no effective traceability mechanism in the assembly process. Once quality problems occur in the product, it is difficult to quickly and accurately locate the root cause of the problem, increasing the after-sales cost and market risk of the enterprise;

[0007] 4) In terms of die design and manufacturing, traditional processes are difficult to meet the production requirements of oil pumps with complex structures. The die precision and surface quality need to be improved. During the machining process, the machining ability for high-precision components is insufficient, and it is impossible to ensure that the dimensional accuracy and geometric tolerance of the product meet the high standards of modern engines;

[0008] In summary, the oil pumps in the prior art have obvious deficiencies in terms of structure, performance, quality control, and manufacturing processes, and cannot meet the growing high-performance and low-fuel-consumption requirements of automotive engines. Therefore, it is urgent to develop more advanced oil pump technologies and products, which is of great significance for promoting the sustainable development of the automotive industry. Summary of the Invention

[0009] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is to provide an oil pump for an automotive engine and a preparation process that can effectively solve the above-mentioned technical problems.

[0010] To achieve the above object, the present invention provides an oil pump for an automotive engine, including a pump body, which together with the pump cover forms a closed space for oil flow;

[0011] A drive shaft, passing through the pump body and the rotor, is connected to the engine and is used to drive the rotor and the blades to work;

[0012] A rotor, sleeved on the drive shaft;

[0013] Blades, several blades are installed in the slots of the rotor and can slide in the slots;

[0014] A swing ring, surrounding the outside of the rotor and the blades;

[0015] A filter assembly, installed on the pump cover and located at the oil inlet of the oil pump, is used to filter impurities in the oil.

[0016] An adjusting spring, arranged in the pump body and connected to the swing ring, is used to control the position of the swing ring;

[0017] Further, the filter assembly includes a filter screen cover connected to the pump cover, and a filter screen is arranged on the filter screen cover; it also includes a safety valve spring and a steel ball arranged in the oil passage of the pump body for oil reflux.

[0018] Further, it also includes a first sliding seal and a second sliding seal, arranged on the inner wall of the pump body at the sliding connection of the swing ring. First sliding sealing rings and second sliding sealing rings are respectively arranged on the first sliding seal and the second sliding seal, and the first sliding sealing ring and the second sliding sealing ring play a sealing role; a sliding pin is arranged between the pump body and the swing ring.

[0019] Further, it also includes a first retaining ring and a second retaining ring, sleeved on the drive shaft and respectively located at the upper and lower ends of the rotor for axial positioning.

[0020] The preparation process of the oil pump for an automotive engine includes

[0021] S1: Pump body casting: Pour molten metal into the mold cavity to form a pump body blank,

[0022] S2: Machining: Perform turning, milling, drilling, and boring operations on the rough pump body;

[0023] S3: Rotor manufacturing and flaw detection: Perform flaw detection on the machined rotor to ensure no internal defects in the rotor;

[0024] S4: Manufacture the drive shaft, blades, swing ring, regulating spring, and safety valve spring;

[0025] S5: Component cleaning and inspection: Clean the machined components, and then perform inspections. After passing the inspections, they can be assembled;

[0026] S6: Assembly traceability: Record the assembly process of each oil pump.

[0027] Further, before S1, it also includes designing and manufacturing the pump body mold; the mold manufacturing specifically includes,

[0028] Digital twin modeling: Perform a full - range scan of the pump body model to obtain three - dimensional data. Based on the obtained three - dimensional data, construct a digital twin model of the mold, and perform multiple rounds of simulation analysis and optimization on the structure and dimensions of the mold in a virtual environment to discover and correct potential problems in advance;

[0029] Selective laser melting 3D printing of the initial mold: Using selective laser melting 3D printing technology, select the mold material, and directly print the initial shape of the mold by layer - by - layer melting and depositing metal powder according to the optimized digital twin model;

[0030] Grinding process: Grind the 3D - printed initial mold using a five - axis linkage grinding machine equipped with a nano - level grinding wheel. During the processing, use an on - line measurement system to monitor the dimensions and surface shape of the mold in real time, and adjust the grinding parameters in real time according to the measurement data to ensure that the dimensional accuracy of each part of the mold reaches within ±0.005 mm and the surface roughness reaches below Ra0.1 μm;

[0031] Electrical discharge texturing: Adopt electrical discharge texturing technology, and control the electrode to discharge on the mold surface by computer to machine the required texture pattern;

[0032] Ion implantation strengthening treatment: Ionize alloy elements and inject them into the surface layer of the mold to form a strengthening layer.

[0033] Further, the pump body casting in S1 specifically includes:

[0034] Before injecting the molten metal, pre - heat the mold to 180 - 220 °C, and evenly spray a layer of mold release agent on the surface of the mold cavity to form a thin isolation layer;

[0035] Put the prepared aluminum alloy raw materials into the melting furnace for melting, and control the melting temperature at 700 - 750 °C to fully melt the alloy and mix it evenly. During the melting process, degassing and slag removal treatments are carried out. By blowing inert gas into the molten metal, the gas and inclusions in the molten metal are removed;

[0036] Pour the melted molten metal into the mold cavity through the gate, and control the filling speed at 0.5 - 1.0 m / s; at the same time, prevent air from being involved during the filling process;

[0037] Apply pressure after the filling is completed, with the pressure ranging from 50 - 100 MPa, and the holding pressure time is 1 - 2 s for every 1 mm thickness;

[0038] Control the cooling speed of the mold, set up cooling water channels, and introduce cooling water for forced cooling. The position where the pump body thickness is greater than 5 mm is the thick wall, and the position where the pump body is less than 5 mm is the thin wall. The cooling water flow rate of the thick wall is controlled at 1 - 2 m / s, and for the thin wall part, in order to control the cooling water flow rate at 10 - 20 °C / s, so that the pump body blank is cooled evenly;

[0039] When the cooling temperature of the pump body blank is lower than 200 °C, open the mold for demolding. After demolding, conduct preliminary cleaning on the pump body blank to remove surface impurities.

[0040] Further, in S3, the specific steps for machining the rotor include:

[0041] S31: Rough machining

[0042] S311: According to the three - dimensional model data of the rotor, set the laser scanning parameters. The laser power is 300 - 400 W, the scanning speed is 800 - 1200 mm / s, the powder spreading thickness is 30 - 50 μm, and layer by layer melt and stack the powder to manufacture a blank;

[0043] S312: Clamp the rotor blank on the milling machine, formulate layer - by - layer milling according to the shape and size of the rotor, set the milling speed at 15000 - 20000 r / min, the feed rate at 0.1 - 0.2 mm / z, and control the cutting depth at 0.5 - 1 mm; conduct rough machining on the rotor blank;

[0044] S32: First finish machining

[0045] S321: Take the rotor after rough machining as the anode, select a stainless - steel cathode, and by controlling the temperature of the electrolyte at 30 - 40 °C, the concentration at 180 - 220 g / L, and the machining voltage at 8 - 12 V, make the metal on the surface of the rotor dissolve evenly under the action of the electric field;

[0046] S322: Add nanoscale alumina abrasive in the electrolyte and make it evenly dispersed through a stirring device. The cathode adopts a structure with a flexible grinding tool. During the processing, the cathode vibrates to cut and polish the surface of the rotor. Control the machining current density at 10 - 15 A / dm 2 , and the processing time is 20 - 30 min to make the surface roughness of the rotor reach Ra0.8 - 1.6 μm;

[0047] S33: Second fine machining

[0048] S331: Clamp the rotor after the first fine machining on a CNC grinding machine and grind it with a grinding wheel. During rough grinding, set the grinding depth at 0.05 - 0.1 mm, the grinding wheel linear speed at 30 - 40 m / s, and the workpiece feed speed at 10 - 20 mm / min; during fine grinding, reduce the grinding depth to 0.01 - 0.02 mm, increase the grinding wheel linear speed to 40 - 50 m / s, and reduce the workpiece feed speed to 5 - 10 mm / min; by precisely controlling the grinding parameters, ensure that the dimensional accuracy of the rotor reaches ±0.005 mm and the roundness error is controlled within 0.002 mm.

[0049] Furthermore, the assembly traceability in S6 includes:

[0050] S61: Build an assembly traceability management platform, use a database server to store various traceability data, provide an operation interface for users through the server, support assembly personnel to access on the device, and realize real-time data entry and query;

[0051] S62: Information collection

[0052] S621: Before the parts enter the assembly workshop, obtain the batch information by scanning the QR code or barcode on the parts, and upload the information to the traceability system by the scanning device, which is associated with the assembly task of the corresponding oil pump;

[0053] S622: Equip each assembly personnel with a work card with a built-in chip or QR code. Before the assembly starts, the assembly personnel scan the work card on the workshop terminal device. The system records the assembly task of the oil pump responsible by this person. At the same time, the terminal device monitors the operation steps of the assembly personnel in real time;

[0054] S623: Install a timestamp device at each assembly station, which synchronizes the time with the traceability system. After the assembly personnel complete each assembly step, record the completion time of this step by scanning the operation or clicking the station terminal to confirm;

[0055] S63: Data storage and management

[0056] S631: Create different data tables in the database to store the basic information of the oil pump, the information of component batches, the information of assembly personnel, the information of assembly time, the assembly operation records, and the quality inspection results respectively; each data table is associated through the oil pump serial number;

[0057] S632: Adopt a combination of regular full - volume backup and real - time incremental backup to back up the data to a remote server to prevent data loss;

[0058] S64: Traceability process and application

[0059] S641: When quality problems occur during the subsequent inspection and use of the oil pump, the quality personnel input the oil pump serial number in the traceability system, and the system quickly locates the assembly records of the oil pump;

[0060] S642: The traceability system takes the time axis and the assembly process as clues to display all the assembly information of the oil pump; the quality personnel can view the component batches used during the assembly process to judge whether there are batch - related quality problems; view the operation records of the assembly personnel to analyze whether there are operation mistakes; combine the assembly time and the inspection results to investigate the assembly quality differences in different time periods and determine the root cause of the problem;

[0061] S643: The traceability system conducts statistical analysis on the assembly data and generates an assembly quality report.

[0062] Furthermore, after S6, it also includes:

[0063] Performance test: The assembled oil pump undergoes a performance test to simulate the working conditions of the engine under different conditions and detect the performance indicators of the oil pump such as flow rate, pressure, variable displacement pressure, and safety valve opening pressure;

[0064] Packaging and warehousing: Package the oil pumps that pass the performance test.

[0065] The beneficial effects of the present invention are as follows:

[0066] 1) Precise adaptation to working conditions and energy consumption reduction: The oil pump of the present invention can adjust the displacement according to the engine working conditions through the cooperation of the swing ring and the adjusting spring. When the engine is under low load, it reduces the oil output, reduces the driving power of the oil pump, and thus reduces the engine fuel consumption, conforming to the energy - saving trend of automotive engines and meeting the requirements of strict fuel consumption regulations;

[0067] 2) Optimized structural design to ensure stable operation: The pump body and the pump cover form a closed space to prevent oil leakage; the drive shaft drives the rotor and the blades, and cooperates with the swing ring to adjust the volume of the oil pumping chamber to ensure normal oil pumping; the filter component filters impurities, and the safety valve spring and steel ball prevent excessive pressure, comprehensively ensuring good lubrication of all components of the engine, reducing wear, extending the service life of the engine, and improving the operation stability and reliability;

[0068] 3) Mold manufacturing innovation to improve precision and quality: In the pump body mold manufacturing process, digital twin modeling is used for simulation and optimization. Combining processes such as selective laser melting 3D printing, grinding, electrical discharge texturing, and ion implantation strengthening treatment, the preparation process of the present invention not only improves the mold precision and quality, ensures high-quality pump body blanks, reduces casting defects, but also enables precise forming of complex structures, improves production efficiency, and reduces material loss;

[0069] 4) Fine rotor processing to ensure dimensional accuracy: Multiple advanced processing techniques are used in rotor manufacturing. First, a blank is made by laser melting deposition, then rough milling is carried out, followed by the first precision machining using electrochemical dissolution and flexible grinding, and finally precise grinding on a CNC grinder. This series of processes strictly control the rotor dimensional accuracy, making its dimensional accuracy reach ±0.005 mm, the roundness error controlled within 0.002 mm, the surface roughness meeting the standards, and at the same time, flaw detection is carried out to ensure no internal defects, greatly improving the rotor quality;

[0070] 5) Comprehensive assembly traceability for easy problem troubleshooting: A perfect assembly traceability system is established. By building a management platform, collecting component batch information, recording assembly personnel and operation time, etc., a detailed record of the assembly process of each oil pump is achieved. Once a quality problem occurs in the product, the problem can be quickly located, and it can be accurately judged whether it is a component batch problem or an assembly operation error, facilitating the enterprise to take targeted measures, such as recalling specific batches of components or training assembly personnel, to continuously improve product quality.

[0071] 6) Strict performance testing to ensure product reliability: The assembled oil pump needs to undergo performance tests to simulate different engine operating conditions and detect performance indicators such as flow rate, pressure, variable displacement pressure, and safety valve opening pressure. Only products that meet the design requirements and relevant standards can enter the next process, which effectively ensures the reliability of the oil pump in actual use and reduces the probability of failures. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 is a schematic structural diagram of a specific embodiment of the present invention.

[0073] Figure 2 is a three-dimensional structural diagram of the present invention.

[0074] Figure 3 is a first three-dimensional structural diagram of the pump cover of the present invention.

[0075] Figure 4 is a second three-dimensional structural diagram of the pump cover.

[0076] Figure 5 is a schematic structural diagram of the present invention without the pump cover.

[0077] Figure 6 It is a first three-dimensional structure schematic diagram of the swing ring cooperating with components such as the rotor.

[0078] Figure 7 is Figure 6 the second three-dimensional structure schematic diagram in

[0079] Figure 8 It is a structure schematic diagram of the rotor cooperating with components such as the blades.

[0080] Figure 9 It is a structure schematic diagram of the pump body in the present invention. Detailed implementation manners

[0081] The present invention will be further described below in conjunction with the drawings and embodiments:

[0082] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0083] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "set", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0084] As Figures 1 to 9 shown:

[0085] An oil pump for an automotive engine includes

[0086] a pump body 1. The pump body 1 is the basic framework of the oil pump. A pump cover 2 is installed above the pump body 1 and is fixedly connected by screws. The pump body 1 provides an installation position for other components and together with the pump cover 2 forms a closed space for oil flow to prevent oil leakage;

[0087] a drive shaft 5 that penetrates the pump body 1 and the rotor 6 and is connected to the engine. It is driven to rotate by the power of the engine and is used to drive the rotor 6 and the blades 7 to work;

[0088] The rotor 6 is sleeved on the transmission shaft 5; the blades 7, a plurality of blades 7 are installed in the grooves of the rotor 6 and can slide in the grooves; when the transmission shaft 5 drives the rotor 6 to rotate, the blades 7 are pressed against the inner wall of the swing ring 8 under the action of centrifugal force and oil pressure, sucking the oil from the oil inlet and pumping it to the oil outlet;

[0089] The swing ring 8 surrounds the outside of the rotor 6 and the blades 7; the swing ring 8 can swing within a certain range, and cooperate with the blades 7 to change the volume of the oil pumping chamber, realizing the adjustment of the displacement of the oil pump;

[0090] The filter assembly 9 is installed on the pump cover 2, at the oil inlet of the oil pump, and is used to filter impurities in the oil.

[0091] The adjusting spring 10 is arranged in the pump body 1 and connected to the swing ring 8. The adjusting spring 10 applies a pre-tightening force to the swing ring 8 to control the position of the swing ring 8; thereby assisting in adjusting the displacement of the oil pump.

[0092] The filter assembly 9 includes a filter screen cover 11 connected to the pump cover 2, and a filter screen 12 is arranged on the filter screen cover 11. The filter screen filters impurities in the oil, preventing impurities from entering the oil pump and the engine, and protecting the components of the engine.

[0093] The present invention also includes a safety valve spring 13 and a steel ball 15 arranged in the oil passage of the pump body 1. When the internal pressure of the oil pump is too high, the oil pressure overcomes the elastic force of the safety valve spring 13 and pushes open the steel ball 15, for part of the oil to flow back. To prevent damage to system components due to too high oil pressure;

[0094] Furthermore, it also includes a first sliding seal 16 and a second sliding seal 17, arranged on the inner wall of the pump body 1, at the sliding connection of the swing ring 8. First sliding sealing rings 18 and second sliding sealing rings 19 are respectively arranged on the first sliding seal 16 and the second sliding seal 17, and the first sliding sealing rings 18 and the second sliding sealing rings 19 play a sealing role; for preventing oil leakage during the sliding process of components and ensuring the normal operation of the oil pump.

[0095] The sliding pin 20 is arranged between the pump body 1 and the swing ring 8. The sliding pin 20 provides guidance and support for the swing of the swing ring 8, ensuring the accuracy of its movement.

[0096] Preferably, it also includes a first retaining ring 21 and a second retaining ring 22, sleeved on the transmission shaft 5, and respectively located at the upper and lower ends of the rotor 6, for axial positioning; preventing components from axially moving and ensuring the normal working position of components.

[0097] The preparation process of the oil pump for an automotive engine includes

[0098] S1: Pump body casting: Inject molten metal into the mold cavity to form the rough pump body. During the casting process, parameters such as temperature, pressure, and filling speed need to be controlled to ensure the density and dimensional accuracy of the rough pump body and reduce casting defects.

[0099] S2: Machining: Perform turning, milling, drilling, and boring operations on the rough pump body; use high-precision machining equipment to ensure that the dimensional accuracy, form and position tolerances, and surface roughness of each part meet the design requirements, especially the machining accuracy of key parts such as internal oil channels and mounting holes.

[0100] S3: Rotor manufacturing and flaw detection: Perform flaw detection on the processed rotor, such as using magnetic particle flaw detection or ultrasonic flaw detection methods, to ensure that there are no defects (such as cracks and pores) inside the rotor and guarantee the rotor quality.

[0101] S4: Manufacture the drive shaft, blades, swing ring, adjusting spring, and safety valve spring; the machining of each component needs to meet the dimensional accuracy and performance requirements.

[0102] S5: Component cleaning and inspection: Clean the processed components to remove surface oil, iron filings, and other impurities; then perform inspections (including dimensional measurement, form and position tolerance inspection, surface quality inspection, performance testing, etc.). After passing the inspection, assembly can be carried out;

[0103] Assembly: In a clean assembly environment, install each component in sequence according to the assembly process requirements. First, install the positioning pins to determine the relative positions of the components, then install sealing components such as sliding seals and sliding sealing rings, then install moving components such as the rotor, blades, and swing ring, then install control components such as the adjusting spring, safety valve spring, and steel balls, and finally install the pump cover, filter screen, filter screen cover, etc. During the assembly process, attention needs to be paid to controlling the assembly clearance and tightening torque to ensure the assembly quality.

[0104] S6: Assembly traceability: Establish an assembly traceability system to record the assembly process of each oil pump, including information such as component batches, assembly personnel, and assembly time, so as to quickly trace the cause in case of quality problems.

[0105] Preferably, before the above S1, it also includes designing and manufacturing the pump body mold; ensuring the mold accuracy and quality to provide a basis for the formation of the pump body; the mold manufacturing specifically includes,

[0106] Digital twin modeling: Abandon the traditional way of designing the mold only relying on two-dimensional drawings. Use three-dimensional modeling software, combine laser scanning technology to scan the model of the pump body comprehensively to obtain three-dimensional data, and build a digital twin model of the mold based on the obtained three-dimensional data. Conduct multiple rounds of simulation analysis and optimization on the structure, dimensions, demolding method, etc. of the mold in a virtual environment, discover potential problems in advance and make corrections;

[0107] Selective Laser Melting (SLM) 3D printing of the initial mold: Using the selective laser melting 3D printing technology, a special metal powder material for molds with high strength and high wear resistance (such as H13 tool steel powder) is selected. According to the optimized digital twin model, the initial shape of the mold is directly printed by layer-by-layer melting and stacking of metal powder. Compared with traditional machining or casting methods, this additive manufacturing method can more accurately achieve the forming of complex structures, reduce material waste, and improve the efficiency of mold manufacturing at the same time.

[0108] Grinding process: The 3D-printed initial mold is subjected to ultra-precision grinding. A high-precision five-axis linkage grinding machine equipped with a nano-level precision grinding wheel is used. During the processing, an on-line measurement system is used to monitor the size and surface shape of the mold in real time, and the grinding parameters (such as grinding wheel speed, feed speed, grinding depth, etc.) are adjusted in real time according to the measurement data to ensure that the dimensional accuracy of each part of the mold reaches within ±0.005 mm and the surface roughness reaches below Ra0.1 μm.

[0109] Electrical Discharge Texturing (EDT): For parts of the mold surface with special texture requirements (such as the surface affecting the demolding effect or appearance of the pump body), the electrical discharge texturing technology is used. The electrode is controlled by a computer to discharge on the mold surface to accurately machine the required texture pattern. This processing method can achieve highly accurate and consistent surface texture without affecting the dimensional accuracy of the mold, improving the quality of the mold and the quality of the pump body after forming.

[0110] Ion implantation strengthening treatment: To further improve the hardness, wear resistance and corrosion resistance of the mold, the mold is subjected to ion implantation strengthening treatment. After ionizing alloying elements (nitrogen, carbon, boron, etc.), they are implanted into the surface layer of the mold under the action of high voltage to form a strengthening layer with excellent performance. This strengthening layer can not only improve the service life of the mold, but also ensure the stability of the mold accuracy during long-term use.

[0111] Preferably, the casting of the pump body in S1 specifically includes:

[0112] Before injecting the molten metal, the mold is preheated to 180 - 220 °C. This can reduce the temperature difference between the molten metal and the mold and reduce casting defects caused by rapid cooling. At the same time, a release agent is evenly sprayed on the surface of the mold cavity to form a thin isolation layer, which facilitates the smooth demolding of the pump body blank after forming and does not affect the surface quality of the blank.

[0113] Put the prepared aluminum alloy raw materials into the melting furnace for melting. Use an electric resistance furnace or an induction furnace, and control the melting temperature at 700 - 750 °C to fully melt the alloy and mix it evenly. During the melting process, carry out degassing and slag removal treatments. By blowing inert gas (such as argon) into the molten metal or adding a refining agent, remove the gas and inclusions in the molten metal and improve the purity of the molten metal.

[0114] Inject the melted molten metal into the mold cavity through the gate. The filling speed is adjusted according to the complexity and size of the pump body. For pump bodies with relatively simple structures and small sizes, the filling speed is controlled at 0.5 - 1.0 m / s; for pump bodies with complex structures and fine structures such as thin walls or ribs, the filling speed is appropriately reduced to 0.2 - 0.5 m / s to ensure that the molten metal can fill the cavity smoothly and completely, avoiding defects such as insufficient pouring and cold shuts. At the same time, during the filling process, keep the liquid level height of the molten metal at the gate stable to prevent air from being involved.

[0115] Apply pressure after the filling is completed to further compact the molten metal under the action of pressure and improve the density of the pump body blank. The pressure magnitude is adjusted according to the requirements of the pump body and the mold design, and is between 50 - 100 MPa. The holding pressure time is determined according to the thickness of the pump body, with 1 - 2 s of holding pressure for every 1 mm of thickness to ensure that the molten metal solidifies fully and undergoes feeding.

[0116] Control the cooling speed of the mold. Different cooling methods are used for the thick - wall and thin - wall parts of the pump body. Cooling water channels can be set in the thick - wall parts of the mold to introduce cooling water for forced cooling. The position where the pump body thickness is greater than 5 mm is the thick - wall part, and the position where the pump body is less than 5 mm is the thin - wall part. The cooling water flow rate in the thick - wall part is controlled at 1 - 2 m / s to rapidly cool the thick - wall part; for the thin - wall part, to avoid cracks caused by excessive cooling, the cooling water flow rate is controlled at 10 - 20 °C / s to cool the pump body blank evenly and ensure its dimensional accuracy.

[0117] After the pump body blank cools below 200 °C, open the mold for demolding. After demolding, conduct preliminary cleaning on the pump body blank to remove surface impurities (impurities include release agent residues, flash, and burrs, etc.).

[0118] In addition, during the entire casting process, devices such as temperature sensors, pressure sensors, and flow sensors can be used to monitor parameters such as temperature, pressure, and filling speed in real - time. Once it is found that the parameters deviate from the set range, immediately adjust through an automatic control system or manual intervention to ensure the stability of the casting process and produce high - quality pump body blanks.

[0119] Preferably, in step S3, the specific steps for machining the rotor include:

[0120] S31: Rough machining

[0121] S311: Based on the 3D model data of the rotor, the laser scanning path, power, scanning speed and other parameters are accurately set in the SLM equipment. The laser power is 300-400W, the scanning speed is 800-1200mm / s, the powder thickness is 30-50μm, and the powder is melted and accumulated layer by layer to quickly produce a blank close to the final shape of the rotor; greatly reducing the subsequent processing allowance.

[0122] S312: Clamp the rotor blank on a high-precision high-speed milling machine and use carbide tools. According to the shape and size of the rotor, layered milling is formulated, the milling speed is set to 15000-20000r / min, the feed rate is 0.1-0.2mm / z, and the cutting depth is controlled at 0.5-1mm; the rotor blank is rough-machined using the efficient removal ability of high-speed milling to further approach the final size, laying the foundation for subsequent fine machining. During the milling process, a spray cooling system is used with a degradable plant-based cutting fluid as the cooling medium to achieve good cooling and lubrication effects, improve the quality of the machined surface, and reduce tool wear.

[0123] S32: First finishing

[0124] S321: The rough-machined rotor is used as the anode, and a stainless steel cathode is selected. The electrolyte is a mixed solution of sodium chloride and additives with an optimized formula. By controlling the temperature of the electrolyte at 30-40℃, the concentration at 180-220g / L, and the processing voltage at 8-12V, the metal on the rotor surface is evenly dissolved under the action of the electric field; a certain thickness of material is removed to further reduce the processing allowance. This processing method can remove materials efficiently, with low processing force, and will not cause mechanical stress and deformation to the rotor.

[0125] S322: Add nano-alumina abrasives to the electrolyte and disperse them evenly through a stirring device. The cathode adopts a structure with a flexible abrasive. During the processing, the cathode vibrates to cut and polish the rotor surface. The processing current density is controlled at 10-15A / dm 2 The processing time is 20-30min, so that the surface roughness of the rotor reaches Ra0.8-1.6μm; at the same time, the dimensional accuracy is further improved to prepare for the final finishing.

[0126] S33: Second finishing

[0127] S331: Clamp the rotor after the first precision machining on a high-precision CNC grinding machine, and select a CBN (cubic boron nitride) grinding wheel. When grinding with the grinding wheel, during rough grinding, the grinding depth is set to 0.05 - 0.1 mm, the grinding wheel linear speed is 30 - 40 m / s, and the workpiece feed speed is 10 - 20 mm / min; during finish grinding, the grinding depth is reduced to 0.01 - 0.02 mm, the grinding wheel linear speed is increased to 40 - 50 m / s, and the workpiece feed speed is reduced to 5 - 10 mm / min; by precisely controlling the grinding parameters, ensure that the dimensional accuracy of the rotor reaches ±0.005 mm, and the roundness error is controlled within 0.002 mm; during the grinding process, use an on-line measurement system to monitor the dimensional changes of the rotor in real time. Once a deviation is found, immediately adjust the grinding parameters for correction.

[0128] Preferably, the assembly traceability in S6 includes:

[0129] S61: Adopt a B / S architecture based on cloud computing to build a dedicated assembly traceability management platform. Use a database server to store various traceability data, such as a MySQL database. Its powerful data storage and management capabilities can efficiently process a large amount of assembly information. Provide an operation interface for users through a Web server, support different roles such as assembly workers and quality management personnel to conveniently access on devices such as workshop terminals and office computers, and realize real-time data entry and query;

[0130] S62: Information collection

[0131] S621: Before the parts enter the assembly workshop, obtain batch information by scanning the QR code or bar code on the parts. The QR code or bar code contains key data such as the supplier, production date, batch number, etc. The scanning device automatically uploads the information to the traceability system and associates it with the assembly task of the corresponding oil pump;

[0132] S622: Equip each assembly worker with a dedicated work card with an RFID chip or QR code inside. Before the assembly starts, the assembly worker scans the work card on the workshop terminal device. The system automatically records the oil pump assembly task responsible for by this person. At the same time, the terminal device monitors the operation steps of the assembly worker in real time; ensure that the operation is standardized and meets the process requirements, and remind and record in time when the operation is abnormal.

[0133] S623: Install a timestamp device at each assembly station. This device synchronizes the time with the traceability system. After the assembly worker completes each assembly step, through scanning operation or clicking to confirm on the station terminal, the system automatically records the completion time of this step; accurate to seconds. For special situations such as waiting and interruption during the assembly process, detailed time records and reason remarks are also made.

[0134] S63: Data storage and management

[0135] S631: Create different data tables in the database to store the basic information of the oil pump (model, serial number, etc.), component batch information, assembly personnel information, assembly time information, assembly operation records (operation steps, tools used, etc.), and quality inspection results (inspection items, whether qualified, etc.); establish associations among the data tables through the oil pump serial number; facilitate querying and tracing.

[0136] S632: Adopt a combination of regular full backups and real-time incremental backups to back up the data to a remote server to prevent data loss; at the same time, set up strict user permission management, where different roles (assembly personnel, team leaders, quality supervisors, etc.) have different data access levels and operation permissions to ensure data security. For example, assembly personnel can only view and enter the assembly data they are responsible for, and quality supervisors can view all assembly data and quality reports.

[0137] S64: Tracing process and application

[0138] S641: When quality problems occur during subsequent inspections and use of the oil pump, quality personnel enter the oil pump serial number in the tracing system, and the system quickly locates the assembly records of the oil pump;

[0139] S642: The tracing system uses the timeline and assembly process as clues to display all the assembly information of the oil pump; quality personnel can view the component batches used during the assembly process to determine whether there are batch quality problems; view the operation records of the assembly personnel to analyze whether there are operation mistakes; combine the assembly time and inspection results to check the assembly quality differences in different time periods and determine the root cause of the problem; take corresponding improvement measures, such as recalling specific batches of components and providing targeted training to assembly personnel.

[0140] S643: The tracing system regularly conducts statistical analysis on the assembly data to generate assembly quality reports. Such as the qualification rate of each assembly station, the product quality situation of different component suppliers, etc. The enterprise optimizes the assembly process and adjusts the supplier cooperation strategy according to the report data to continuously improve product quality.

[0141] Preferably, after S6, it further includes:

[0142] Performance test: Conduct a performance test on the assembled oil pump to simulate the working conditions of the engine under different conditions and detect the performance indicators of the oil pump such as flow rate, pressure, variable displacement pressure, and safety valve opening pressure; ensure that it meets the design requirements and relevant standards.

[0143] Packaging and warehousing: Package the oil pump that has passed the performance test. Prevent damage during transportation and storage; after packaging, store it in the warehouse and wait for shipment.

[0144] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field based on the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art should fall within the protection scope determined by the claims.

Claims

1. An oil pump for an automotive engine, characterized in that: including a pump body (1), which together with a pump cover (2) forms a closed space for oil flow; a transmission shaft (5), which penetrates the pump body (1) and the rotor (6), is connected to the engine, and is used to drive the rotor (6) and the blades (7) to work; a rotor (6), which is sleeved on the transmission shaft (5); blades (7), several blades (7) are installed in the slots of the rotor (6) and can slide in the slots; a swing ring (8), which surrounds the outside of the rotor (6) and the blades (7); a filter assembly (9), which is installed on the pump cover (2) and is located at the oil inlet of the oil pump, and is used to filter impurities in the oil. a regulating spring (10), which is arranged in the pump body (1) and is connected to the swing ring (8), and is used to control the position of the swing ring (8).

2. The oil pump for an automotive engine according to claim 1, characterized in that: The filter assembly (9) includes a filter screen cover (11) connected to the pump cover (2), and a filter screen (12) is arranged on the filter screen cover (11); it also includes a safety valve spring (13) and a steel ball (15) arranged in the oil passage of the pump body (1) for oil reflux.

3. The oil pump for an automotive engine according to claim 2, characterized in that: It also includes a first sliding seal (16) and a second sliding seal (17), which are arranged on the inner wall of the pump body (1) at the sliding connection of the swing ring (8). First sliding sealing rings (18) and second sliding sealing rings (19) are respectively arranged on the first sliding seal (16) and the second sliding seal (17), and the first sliding sealing ring (18) and the second sliding sealing ring (19) play a sealing role; a sliding pin (20) is arranged between the pump body (1) and the swing ring (8).

4. The oil pump for an automotive engine as claimed in claim 3, characterized in that: It also includes a first retaining ring (21) and a second retaining ring (22), which are sleeved on the transmission shaft (5) and are respectively located at the upper and lower ends of the rotor (6) for axial positioning.

5. A preparation process for an oil pump for an automotive engine as described in claim 4, characterized in that, including S1: Pump body casting: Pour molten metal into the mold cavity to form a pump body blank, S2: Machining: Perform turning, milling, drilling, and boring operations on the pump body blank; S3: Rotor manufacturing and flaw detection: Perform flaw detection on the processed rotor to ensure that there are no defects inside the rotor; S4: Manufacture the transmission shaft, blades, swing ring, regulating spring, and safety valve spring; S5: Component cleaning and inspection: Clean the processed components, and then perform inspection. After passing the inspection, assembly can be carried out; S6: Assembly traceability: Record the assembly process of each oil pump.

6. A preparation process for an oil pump for an automotive engine as described in claim 5, characterized in that, Before the S1, it also includes designing and manufacturing the pump body mold; among which the manufacturing of the mold specifically includes, Digital twin modeling: Perform a full - range scan on the model of the pump body to obtain three - dimensional data, construct a digital twin model of the mold based on the obtained three - dimensional data, perform multiple rounds of simulation analysis and optimization on the structure and dimensions of the mold in a virtual environment, and discover and correct potential problems in advance; Selective laser melting 3D printing of the initial mold: Use selective laser melting 3D printing technology, select mold materials, and directly print the initial shape of the mold by layer - by - layer melting and stacking of metal powder according to the optimized digital twin model; Grinding process: The initial mold printed by 3D is subjected to grinding process. A five-axis linkage grinding machine equipped with a nanoscale grinding wheel is used. During the processing, an on-line measurement system is used to monitor the size and surface shape of the mold in real time, and the grinding parameters are adjusted in real time according to the measurement data to ensure that the dimensional accuracy of each part of the mold reaches within ±0.005 mm and the surface roughness reaches below Ra0.1 μm; Electrical discharge texturing process: The electrical discharge texturing technology is adopted, and the electrode is controlled by a computer to discharge on the mold surface to machine the required texture pattern; Ion implantation strengthening treatment: After ionizing alloying element ions, they are implanted into the surface layer of the mold to form a strengthening layer.

7. A preparation process for an oil pump for an automotive engine as described in claim 6, characterized in that, The specific steps of the pump body casting in S1 include: Before injecting the molten metal, the mold is preheated to 180 - 220 °C, and a release agent is evenly sprayed on the surface of the mold cavity to form a thin isolation layer; The prepared aluminum alloy raw material is put into a furnace for melting, and the melting temperature is controlled at 700 - 750 °C to fully melt and uniformly mix the alloy. During the melting process, degassing and slag removal treatments are carried out. By blowing inert gas into the molten metal, the gas and inclusions in the molten metal are removed; The molten metal after melting is injected into the mold cavity through the gate, and the filling speed is controlled at 0.5 - 1.0 m / s; at the same time, during the filling process, air entrainment is prevented; After the filling is completed, pressure is applied, and the pressure magnitude is between 50 - 100 MPa. The holding time is 1 - 2 s for each 1 mm thickness; The cooling speed of the mold is controlled, cooling channels are set, and cooling water is introduced for forced cooling. The position where the pump body thickness is greater than 5 mm is the thick wall, and the position where the pump body is less than 5 mm is the thin wall. The cooling water flow rate of the thick wall is controlled at 1 - 2 m / s, and for the thin wall part, in order to control the cooling water flow rate at 10 - 20 °C / s, so that the pump body blank is cooled evenly; When the cooling temperature of the pump body blank is lower than 200 °C, the mold is opened for demolding. After demolding, the pump body blank is preliminarily cleaned to remove surface impurities.

8. A preparation process for an oil pump for an automotive engine as claimed in claim 7, characterized in that, In S3, the specific steps for machining the rotor include: S31: Rough machining S311: According to the three-dimensional model data of the rotor, the laser scanning parameters are set. The laser power is 300 - 400 W, the scanning speed is 800 - 1200 mm / s, the powder laying thickness is 30 - 50 μm, and the powder is melted and deposited layer by layer to manufacture a blank; S312: The rotor blank is clamped on a milling machine. According to the shape and size of the rotor, layer-by-layer milling is formulated. The milling speed is set at 15000 - 20000 r / min, the feed rate is 0.1 - 0.2 mm / z, and the cutting depth is controlled at 0.5 - 1 mm; rough machining is carried out on the rotor blank; S32: First finish machining S321: Taking the rotor after rough machining as the anode and selecting a stainless steel cathode, by controlling the temperature of the electrolyte at 30 - 40 °C, the concentration at 180 - 220 g / L, and the machining voltage at 8 - 12 V, the metal on the surface of the rotor is uniformly dissolved under the action of the electric field; S322: Add nanoscale alumina abrasive in the electrolyte, and make it evenly dispersed through a stirring device. The cathode adopts a structure with a flexible grinding tool. During the processing, the cathode vibrates to cut and polish the surface of the rotor, and control the processing current density at 10 - 15 A / dm 2 , the processing time is 20 - 30 min, so that the surface roughness of the rotor reaches Ra0.8 - 1.6 μm; S33: Second finish machining S331: Clamp the rotor after the first precision machining on a CNC grinding machine and grind it using a grinding wheel. During rough grinding, set the grinding depth to 0.05 - 0.1 mm, the grinding wheel linear speed to 30 - 40 m / s, and the workpiece feed speed to 10 - 20 mm / min; during finish grinding, reduce the grinding depth to 0.01 - 0.02 mm, increase the grinding wheel linear speed to 40 - 50 m / s, and reduce the workpiece feed speed to 5 - 10 mm / min; by precisely controlling the grinding parameters, ensure that the dimensional accuracy of the rotor reaches ±0.005 mm and the roundness error is controlled within 0.002 mm.

9. A preparation process for an oil pump used in an automobile engine as described in claim 8, characterized in that, The assembly traceability in S6 includes: S61: Build an assembly traceability management platform, use a database server to store various traceability data, provide an operation interface for users through the server, support assembly personnel to access on the device, and realize real-time data entry and query; S62: Information collection S621: Before the components enter the assembly workshop, obtain the batch information by scanning the QR code or bar code on the components, and upload the information to the traceability system by the scanning device, which is associated with the assembly task of the corresponding oil pump; S622: Equip each assembly personnel with a work card with an embedded chip or QR code. Before the assembly starts, the assembly personnel scan the work card on the workshop terminal device. The system records the assembly task of the oil pump responsible by this person. At the same time, the terminal device monitors the operation steps of the assembly personnel in real time; S623: Install a timestamp device at each assembly station, which synchronizes the time with the traceability system. After the assembly personnel complete each assembly step, record the completion time of this step by scanning the operation or clicking the station terminal to confirm; S63: Data storage and management S631: Create different data tables in the database to store the basic information of the oil pump, the batch information of the components, the information of the assembly personnel, the assembly time information, the assembly operation records, and the quality inspection results respectively; each data table is associated through the serial number of the oil pump; S632: Adopt a combination of regular full backup and real-time incremental backup to back up the data to an off-site server to prevent data loss; S64: Traceability process and application S641: When quality problems occur during the subsequent inspection and use of the oil pump, the quality personnel enter the serial number of the oil pump in the traceability system, and the system quickly locates the assembly record of this oil pump; S642: The traceability system takes the time axis and the assembly process as clues to display all the assembly information of this oil pump; the quality personnel can view the batch of components used during the assembly process to judge whether there are batch quality problems; view the operation records of the assembly personnel to analyze whether there are operation mistakes; combine the assembly time and the inspection results to check the assembly quality differences in different time periods and determine the root cause of the problem; S643: The traceability system statistically analyzes the assembly data and generates an assembly quality report.

10. A preparation process for an oil pump for an automotive engine as described in claim 9, characterized in that, After S6, it also includes: Performance test: Conduct a performance test on the assembled oil pump, simulate the working conditions of the engine under different conditions, and detect the performance indicators of the oil pump such as flow rate, pressure, variable displacement pressure, and safety valve opening pressure; Packaging and warehousing: Package the oil pump that passes the performance test.

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