Gear beneficial to lubrication and machining method thereof

Abstract

The invention belongs to the technical field of gear bodies, provides an innovative gear which is provided with a tooth crest trimming edge, a tooth root digging root and a tooth surface oil groove structure matched with load and rotation and can optimize lubrication, reduce stress, improve bearing capacity and prolong the service life, and particularly relates to a gear beneficial to lubrication and a machining method thereof. An oil groove is formed in the tooth surface. Lubricating oil can be continuously conveyed to a meshing part along with rotation of a gear, in the rotation process of the gear, the lubricating oil can directionally flow in the oil groove due to centrifugal force and the spiral guiding effect of the oil groove, when the gear rotates, the spiral oil groove is like a spiral conveyor, and the lubricating oil is stably conveyed from one end of the oil groove to the other end of the oil groove. The lubricating oil is accurately conveyed to the gear meshing area, it is ensured that sufficient lubricating oil is supplied at each moment of gear meshing through the continuous conveying mode, and dry friction of the tooth surface caused by untimely lubricating oil supply is effectively avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of gear bodies, and provides an innovative gear having a tooth top trimming, a tooth root digging, and a tooth surface oil groove structure adapted to load and rotation, which can optimize lubrication, reduce stress, and increase load and life, and in particular relates to a gear that is conducive to lubrication and a processing method thereof. Background Art

[0002] In the field of modern mechanical engineering, as mechanical equipment continues to develop towards high speed, heavy load and high precision, the performance requirements for gear transmission systems are becoming increasingly stringent. When traditional gears are running under high load, the tooth surface is prone to stress concentration and insufficient lubrication, leading to adverse consequences such as increased wear, severe heat generation, reduced transmission efficiency and shortened service life. For example, these problems are particularly prominent in key equipment such as large power transmission devices, automotive transmissions, aerospace engine gearboxes in industrial automation production lines. Frequent maintenance and replacement of gears not only increase costs, but also affect the reliability and stability of the overall operation of the equipment.

[0003] Therefore, there is an urgent need for a gear with an optimized tooth shape that is conducive to lubrication, aiming to effectively solve the lubrication and stress problems of traditional gears under complex working conditions and meet the urgent needs of various high-end mechanical equipment for efficient, stable and long-lasting operation of gear transmission. Summary of the invention

[0004] The present invention proposes a gear that is conducive to lubrication and a processing method thereof. The purpose of the present invention is to provide an innovative gear with a tooth top trimming, a tooth root digging and a tooth surface oil groove structure that adapts to load and rotation, which can optimize lubrication, reduce stress, and increase load and life.

[0005] The technical solution of the present invention is as follows: a gear that is conducive to lubrication and a processing method thereof, characterized in that it includes a tooth root, a tooth surface and a tooth top; The tooth roots are provided with excavated roots to avoid stress concentration at the tooth roots and provide space for the storage and flow of lubricating oil at the tooth roots; A tiny oil groove is arranged on the tooth surface. The direction and depth of the oil groove are optimized according to the rotation direction and load conditions of the gear, and is used to guide the lubricating oil to flow on the tooth surface so that the lubricating oil is continuously supplied to the contact area during the gear meshing process.

[0006] As a preferred solution of the present invention, further, the oil groove is spiral, the number of the oil grooves is eight, extending from one end of the gear to the other end, for achieving continuous delivery of lubricating oil to the meshing part as the gear rotates; The oil groove can realize the continuous delivery of lubricating oil to the meshing part as the gear rotates. During the continuous rotation of the gear, the lubricating oil can be continuously guided to the contact area of ​​the tooth surface, ensuring that the meshing part always has sufficient lubricating oil during long-term working process, maintaining a good lubrication state and effectively reducing wear; It helps the lubricant to be distributed more evenly on the tooth surface. The spiral shape allows the lubricant to gradually cover the entire tooth surface during the flow process, avoiding the situation of insufficient local lubrication, promoting the uniform distribution of the lubricant on the tooth surface, reducing the edge effect, making the contact stress distribution of the tooth surface more even during the meshing process, and improving the load-bearing capacity and service life of the gear; Its direction and depth are optimized according to the rotation direction and load conditions of the gears, matching the rotational motion of the gears. It can better utilize the centrifugal force and inertial force generated by the rotation of the gears, guide the lubricating oil to the parts that need lubrication, enhance the lubrication effect, and ensure that the lubricating oil is effectively delivered to the meshing area under different load conditions. A certain amount of storage space is provided for the lubricating oil on the tooth surface. During the operation of the gear, even if there is a brief fluctuation in the oil supply of the lubrication system, the lubricating oil stored in the spiral oil groove can continue to provide lubrication for the meshing parts, thereby improving the stability and reliability of the lubrication system. At the same time, it also provides a clear path for the flow of lubricating oil on the tooth surface, reducing the loss and waste of lubricating oil.

[0007] As a preferred solution of the present invention, further, the tooth top is provided with a trimming edge, and the tooth top is subjected to shaping treatment to make the contact stress distribution of the tooth surface during the meshing process uniform, reduce the edge effect, and promote the uniform distribution of the lubricating oil on the tooth surface. The parameters of the trimming edge are determined and adjusted according to the transmission ratio, module and expected contact stress distribution requirements of the gear.

[0008] As a preferred solution of the present invention, further, the shape and size of the root digging are designed and optimized according to the material properties, load strength and lubrication requirements of the gear.

[0009] As a preferred solution of the present invention, further, the width, depth and spacing of the oil grooves are adaptively designed according to the rotational speed of the gear, the viscosity of the lubricating oil and the oil supply of the lubrication system.

[0010] In addition, to achieve the above-mentioned purpose, the present application also provides a method for processing a gear that is conducive to lubrication, comprising: The root digging processing step has a maximum root digging depth of 2mm, a root digging starting angle of 10° downward from the starting point of the tooth root transition fillet, and an ending angle of 15° upward from the ending point of the tooth root transition fillet. The electrospark machining process is first used for preliminary forming, the electrode is installed on the spindle of the electrospark machine, the gear blank is fixed on the workbench and adjusted, the electrospark machining parameters are set, and the root digging contour is preliminarily processed through the discharge corrosion effect between the electrode and the gear blank. The root digging depth deviation is controlled within ±0.05 times the modulus, and the root digging starting and ending angle deviations are within ±2°. Then, a forming tool is used for fine cutting and trimming, the gear is installed on a CNC lathe or a machining center, a hob is selected, a machining program is written, and the tooth root digging area is finely turned, and the surface roughness is below Ra0.8. After the machining is completed, a profiler is used to detect the shape accuracy and surface quality of the tooth root digging; The oil groove processing step comprises the following steps: the width of the oil groove is 1.5 mm at the inlet end, 0.8 mm at the outlet end, 1 mm at the arc end, 0.3 mm in depth and 5 mm in spacing; the gear blank is mounted on the workbench of a high-precision CNC milling machine; a carbide micro-milling cutter is selected; a CNC milling program is written; the milling cutter speed is set to 5000-20000 rpm, the feed rate is set to 0.01-0.1 mm / z and the cutting depth is set to 0.05-0.3 mm; the milling machine is started to perform milling processing on the gear surface oil groove; during the processing, a measuring tool is used to perform random inspection on the dimensional accuracy of the oil groove; after the processing is completed, the gear surface is cleaned and deburred; The trimming processing step comprises the following steps: mounting the gear on a workbench of a high-precision CNC machining center, using a special milling cutter, writing a CNC machining program, and accurately controlling the motion trajectory of the tool. The tool starts trimming processing at 1.5 mm below the tooth top circle, and cutting is performed with a trimming curvature radius range of 3-5 mm and a trimming length of 6 mm. During the processing, the dimensional accuracy of the trimming contour is monitored in real time by an online measurement system. The position deviation of the starting trimming point is within ±0.05 mm, the trimming curvature radius deviation is within ±0.1 mm, and the trimming length deviation is within ±0.2 mm. After the processing is completed, a three-coordinate measuring instrument is used to comprehensively detect the dimensional accuracy and shape accuracy of the tooth top trimming.

[0011] The beneficial effects of the present invention are: The present invention can realize continuous delivery of lubricating oil to the meshing part as the gear rotates by setting the oil groove. During the rotation of the gear, the lubricating oil will generate a directional flow in the oil groove due to the centrifugal force and the spiral guiding effect of the oil groove. When the gear rotates unidirectionally, the spiral oil groove is like a "screw conveyor" to stably deliver the lubricating oil from one end of the oil groove to the other end, that is, to accurately deliver the lubricating oil to the gear meshing area. This continuous delivery method ensures that there is sufficient lubricating oil supply at every moment of gear meshing, and effectively avoids dry friction on the tooth surface caused by untimely supply of lubricating oil. Compared with no oil groove or straight oil groove, the continuous delivery mechanism of spiral oil groove is more in line with the rotation characteristics of gears. Straight oil grooves may not be able to effectively guide lubricating oil to the meshing part at certain rotation angles, while spiral oil grooves can continue to work throughout the entire rotation cycle. For example, in high-speed rotating gears, spiral oil grooves can ensure that the lubricating oil reaches the meshing area at a stable flow rate and speed, maintaining a good lubrication state.

[0012] The spiral shape of the spiral oil groove makes the distribution of lubricating oil on the tooth surface more uniform. Since the oil groove extends from one end of the gear to the other end, the lubricating oil will gradually cover the entire tooth surface during the flow process. The number and spacing design of the spiral oil grooves also help to evenly distribute the lubricating oil. Take eight spiral oil grooves as an example. They are evenly distributed on the tooth surface, so that the lubricating oil can be supplied to the tooth surface at multiple locations at the same time, reducing the situation of insufficient local lubrication. During the gear meshing process, all parts of the tooth surface require good lubrication to reduce friction and wear. The spiral oil groove can spread the lubricating oil evenly on the contact area of ​​the tooth surface. Whether it is the tooth top, tooth root or the middle of the tooth surface, it can be fully lubricated. Compared with traditional lubrication methods, this can significantly reduce the difference in friction coefficient between tooth surfaces, making the friction of the entire tooth surface more stable and uniform, thereby improving the transmission efficiency of the gear. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0014] Figure 1 It is a schematic diagram of the overall main structure of the present invention; Figure 2 It is a schematic diagram of the local structure of the tooth surface of the present invention; Figure 3 It is a schematic diagram comparing the tooth top trimming and the tooth top non-trimming of the present invention.

[0015] In the figure: 1. Root digging; 2. Edge trimming; 3. Oil groove; 4. Tooth top; 5. Tooth root; 6. Tooth surface. DETAILED DESCRIPTION

[0016] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] Example 1 like Figure 1 , 2 As shown, this embodiment provides a gear that is conducive to lubrication, including a tooth root, a tooth surface and a tooth top; A root excavation is provided on the tooth root to avoid stress concentration at the tooth root and provide space for the storage and flow of lubricating oil at the tooth root; Tiny oil grooves are set on the tooth surfaces. The direction and depth of the oil grooves are optimized according to the rotation direction and load conditions of the gears. They are used to guide the lubricating oil to flow on the tooth surfaces so that the lubricating oil is continuously supplied to the contact area during the gear meshing process.

[0018] The oil groove is spiral-shaped, with eight grooves extending from one end of the gear to the other end, and is used to continuously deliver lubricating oil to the meshing part as the gear rotates; The oil groove can realize the continuous delivery of lubricating oil to the meshing part as the gear rotates. During the continuous rotation of the gear, the lubricating oil can be continuously guided to the contact area of ​​the tooth surface, ensuring that the meshing part always has sufficient lubricating oil during long-term working process, maintaining a good lubrication state and effectively reducing wear; It helps the lubricant to be distributed more evenly on the tooth surface. The spiral shape allows the lubricant to gradually cover the entire tooth surface during the flow process, avoiding the situation of insufficient local lubrication, promoting the uniform distribution of the lubricant on the tooth surface, reducing the edge effect, making the contact stress distribution of the tooth surface more even during the meshing process, and improving the load-bearing capacity and service life of the gear; Its direction and depth are optimized according to the rotation direction and load conditions of the gears, matching the rotational motion of the gears. It can better utilize the centrifugal force and inertial force generated by the rotation of the gears, guide the lubricating oil to the parts that need lubrication, enhance the lubrication effect, and ensure that the lubricating oil is effectively delivered to the meshing area under different load conditions. A certain amount of storage space is provided for the lubricating oil on the tooth surface. During the operation of the gear, even if there is a brief fluctuation in the oil supply of the lubrication system, the lubricating oil stored in the spiral oil groove can continue to provide lubrication for the meshing parts, thereby improving the stability and reliability of the lubrication system. At the same time, it also provides a clear path for the flow of lubricating oil on the tooth surface, reducing the loss and waste of lubricating oil.

[0019] In some embodiments, a trimming edge is provided on the tooth top. By performing shaping treatment on the tooth top, the contact stress distribution on the tooth surface during meshing is evenly distributed, and the edge effect is reduced to promote even distribution of the lubricating oil on the tooth surface. The parameters of the trimming edge are determined and adjusted according to the transmission ratio, module and expected contact stress distribution requirements of the gear.

[0020] In some embodiments, the shape and size of the undercut are designed and optimized based on the material properties, load strength, and lubrication requirements of the gear.

[0021] In some embodiments, the width, depth and spacing of the oil grooves are adaptively designed according to the rotational speed of the gear, the viscosity of the lubricating oil and the oil supply of the lubrication system.

[0022] The embodiment of the present invention further provides a method for processing a gear that is conducive to lubrication, and the method for processing the gear includes: Root digging processing steps, the maximum root digging depth is 2mm, the starting angle of root digging is 10° downward from the starting point of the tooth root transition fillet, and the ending angle is 15° upward from the ending point of the tooth root transition fillet. First, the electrospark machining process is used for preliminary forming. The electrode is installed on the spindle of the electrospark machine tool, the gear blank is fixed on the workbench and adjusted, and the electrospark machining parameters are set. Through the discharge corrosion between the electrode and the gear blank, the root digging contour is initially processed. The root digging depth deviation is controlled within ±0.05 times the modulus, and the root digging starting and ending angle deviations are within ±2°. Then, a forming tool is used for fine cutting and trimming. The gear is installed on a CNC lathe or machining center, a hob is selected, and a machining program is written. The tooth root digging area is finely turned, and the surface roughness is below Ra0.8. After the machining is completed, the shape accuracy and surface quality of the tooth root digging are detected using a profiler. The oil groove processing steps are as follows: the width of the oil groove is 1.5 mm at the inlet end, 0.8 mm at the outlet end, 1 mm at the arc end, 0.3 mm in depth and 5 mm in spacing. The gear blank is mounted on the workbench of a high-precision CNC milling machine. A carbide micro milling cutter is selected. A CNC milling program is written. The milling cutter speed is set to 5000 - 20000 rpm, the feed rate is 0.01 - 0.1 mm / z and the cutting depth is 0.05 - 0.3 mm. The milling machine is started to perform milling of the tooth surface oil groove. During the processing, a measuring tool is used to perform random inspection of the dimensional accuracy of the oil groove. After the processing is completed, the tooth surface is cleaned and deburred. The trimming process steps are as follows: install the gear on the workbench of a high-precision CNC machining center, use a special milling cutter, write a CNC machining program, and accurately control the tool's motion trajectory. The tool starts trimming 1.5mm below the tooth top circle, and the trimming curvature radius ranges from 3 to 5mm and the trimming length is 6mm. During the machining process, the dimensional accuracy of the trimming contour is monitored in real time through an online measurement system. The position deviation of the starting trimming point is within ±0.05mm, the trimming curvature radius deviation is within ±0.1mm, and the trimming length deviation is within ±0.2mm. After machining is completed, a three-coordinate measuring instrument is used to conduct a comprehensive inspection of the dimensional accuracy and shape accuracy of the tooth top trimming.

[0023] Specifically, first, during the design and planning stage of the gear, a professional gear design team uses advanced gear design software to conduct comprehensive and in-depth simulation analysis and calculation based on multiple factors such as the specific application scenario of the gear, the expected workload, the speed range, and the matching lubrication system characteristics. For example, when it is determined that the gear is used in a certain industrial heavy-duty transmission equipment, the expected load intensity is between 800 and 1200N・m, the speed range is 500 to 1500rpm, and the lubrication system uses a lubricating oil with a viscosity of 100cSt and an oil supply of 50ml / min, the software accurately calculates and determines the specific parameters of the tooth root digging structure, the tooth surface oil groove structure, and the tooth top trimming structure.

[0024] For the tooth root digging structure, according to the gear material (such as 40CrNiMoA alloy steel) and load strength, the maximum digging depth is determined to be 2mm, the starting angle of the digging is 10° downward from the starting point of the tooth root transition fillet, and the ending angle is 15° upward from the ending point of the tooth root transition fillet.

[0025] For the tooth surface oil groove structure, according to the gear speed, lubricating oil viscosity and oil supply of the lubrication system, the oil groove width is determined to be 1.5mm at the inlet end, 0.8mm at the outlet end, 0.3mm deep, and 5mm apart. The oil groove is spiral and there are eight of them.

[0026] For the tooth tip trim structure (if any), according to the gear ratio (such as 3:1), module (such as 5mm) and expected contact stress distribution requirements, the starting trim point of the tooth tip trim is determined to be 1.5mm below the tooth tip circle, the trim curvature radius range is 3-5mm, and the trim length is 6mm.

[0027] Next, the gears are manufactured and processed according to the above-mentioned carefully designed processing method. During the root digging process, the gear blank is preliminarily processed in strict accordance with the EDM parameters, and the depth and angle deviations during the processing are closely monitored and the parameters are adjusted in time. Then, the selected hob is used for fine turning on the CNC lathe or machining center, and attention is paid to the optimization and adjustment of parameters such as cutting speed and feed rate to ensure that the surface roughness meets the standards. During the oil groove processing process, processing is carried out on a high-precision CNC milling machine according to the set milling parameters, and the dimensional accuracy is strictly controlled. The frequency of random inspections is increased to ensure the processing quality. After processing, the tooth surface is thoroughly cleaned by combining high-pressure airflow and ultrasonic cleaning. During the edge trimming process (if applicable), precise processing is carried out on the CNC machining center according to the programming, and real-time monitoring and adjustment are carried out using a laser interferometer. After processing, comprehensive inspection is carried out using a three-coordinate measuring instrument.

[0028] After the gears are manufactured, a comprehensive and systematic performance test is carried out. The tooth surface contact stress distribution test adopts high-precision strain gauge measurement technology. High-sensitivity strain gauges are pasted on the key parts of the tooth surface. Professional loading equipment is used to simulate the actual working load, accurately measure the strain value and calculate the stress distribution. The lubrication effect test adopts advanced optical interference method to measure the oil film thickness. High-brightness light sources and high-resolution detectors are reasonably arranged near the tooth surface. The oil film thickness is accurately determined by accurately analyzing the changes in interference fringes. At the same time, a high-precision flow meter is installed between the oil outlet of the lubrication system and the inlet of the tooth surface oil groove to monitor the lubricating oil flow in real time. The gear transmission efficiency test uses high-precision torque sensors and speed sensors, which are installed on the input and output shafts respectively, to accurately measure the torque and speed data, and the transmission efficiency is obtained through professional calculation methods.

[0029] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A gear that facilitates lubrication, characterized in that: Including tooth root, tooth surface and tooth top; The tooth roots are provided with excavated roots to avoid stress concentration at the tooth roots and provide space for the storage and flow of lubricating oil at the tooth roots; An oil groove is arranged on the tooth surface, and the direction and depth of the oil groove are optimized according to the rotation direction and load condition of the gear, so as to guide the lubricating oil to flow on the tooth surface, so that the lubricating oil is continuously supplied to the contact area during the gear meshing process; The oil groove is spiral-shaped, and there are eight of them, extending from one end of the gear to the other end, for realizing continuous delivery of lubricating oil to the meshing part as the gear rotates; Among them, when the gear rotates, the lubricating oil at the root of the tooth is guided by the oil groove to the contact area of ​​the tooth surface. The meshing part has lubricating oil to maintain lubrication. The lubricating oil is evenly distributed on the tooth surface. The lubricating oil covers the entire tooth surface during the flow process. The oil groove matches the rotational movement of the gear, and uses the centrifugal force and inertial force generated by the rotation of the gear to guide the lubricating oil to the part that needs lubrication, and provides storage space for the lubricating oil on the tooth surface. It also provides a path for the flow of the lubricating oil on the tooth surface to enhance the lubrication effect; The tooth top is provided with a trimming edge, and the tooth top is subjected to a shaping treatment so that the contact stress distribution of the tooth surface during the meshing process is uniform, and the edge effect is reduced to promote the uniform distribution of the lubricating oil on the tooth surface. The parameters of the trimming edge are determined and adjusted according to the transmission ratio, module and expected contact stress distribution requirements of the gear.

2. A gear that facilitates lubrication according to claim 1, characterized in that: The shape and size of the rooting are designed and optimized based on the material properties, load strength and lubrication requirements of the gear.

3. A gear that facilitates lubrication according to claim 2, characterized in that: The width, depth and spacing of the oil grooves are adaptively designed according to the rotational speed of the gear, the viscosity of the lubricating oil and the oil supply of the lubricating system.

4. A method for processing a gear that facilitates lubrication, using the gear that facilitates lubrication as claimed in claim 3, characterized in that: include: The root digging processing step has a maximum root digging depth of 2mm, a root digging starting angle of 10° downward from the starting point of the tooth root transition fillet, and an ending angle of 15° upward from the ending point of the tooth root transition fillet. The electrospark machining process is first used for preliminary forming, the electrode is installed on the spindle of the electrospark machine, the gear blank is fixed on the workbench and adjusted, the electrospark machining parameters are set, and the root digging contour is preliminarily processed through the discharge corrosion effect between the electrode and the gear blank. The root digging depth deviation is controlled within ±0.05 times the modulus, and the root digging starting and ending angle deviations are within ±2°. Then, a forming tool is used for fine cutting and trimming, the gear is installed on a CNC lathe or a machining center, a hob is selected, a machining program is written, and the tooth root digging area is finely turned, and the surface roughness is below Ra0.

8. After the machining is completed, a profiler is used to detect the shape accuracy and surface quality of the tooth root digging; The oil groove processing step comprises the following steps: the width of the oil groove is 1.5 mm at the inlet end, 0.8 mm at the outlet end, 1 mm at the arc end, 0.3 mm in depth and 5 mm in spacing; the gear blank is mounted on the workbench of a high-precision CNC milling machine; a carbide micro-milling cutter is selected; a CNC milling program is written; the milling cutter speed is set to 5000-20000 rpm, the feed rate is set to 0.01-0.1 mm / z and the cutting depth is set to 0.05-0.3 mm; the milling machine is started to perform milling processing on the gear surface oil groove; during the processing, a measuring tool is used to perform random inspection on the dimensional accuracy of the oil groove; after the processing is completed, the gear surface is cleaned and deburred; The trimming processing step comprises the following steps: mounting the gear on a workbench of a high-precision CNC machining center, using a special milling cutter, writing a CNC machining program, and accurately controlling the motion trajectory of the tool. The tool starts trimming processing at 1.5 mm below the tooth top circle, and cutting is performed with a trimming curvature radius range of 3-5 mm and a trimming length of 6 mm. During the processing, the dimensional accuracy of the trimming contour is monitored in real time by an online measurement system. The position deviation of the starting trimming point is within ±0.05 mm, the trimming curvature radius deviation is within ±0.1 mm, and the trimming length deviation is within ±0.2 mm. After the processing is completed, a three-coordinate measuring instrument is used to comprehensively detect the dimensional accuracy and shape accuracy of the tooth top trimming.

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