An apparatus for machining lubrication grooves in graphite bearings

Abstract

The application discloses a device for processing graphite bearing lubricating grooves, which comprises a saw blade and a saw blade support for mounting the saw blade, and further comprises a positioning support and a rotation-stopping unit, wherein the positioning support comprises a disc part and a shaft part coaxially arranged on one side of the disc part, a plurality of radial guide grooves are arranged on the disc part, the guide grooves penetrate the disc part along the axial direction and extend to the shaft part by a preset depth, and the rotation-stopping unit is arranged on the outer circumferential surface of the shaft part. The device for processing graphite bearing lubricating grooves solves the defects of the traditional needle processing method through the cooperative design of multiple components. The rigid blade edge of the saw blade is matched with the stable support of the saw blade support, thereby reducing the stress fluctuation during cutting and reducing the risk of block dropping and edge collapse of the graphite material caused by excessive local stress; the coaxial design of the disc part and the shaft part of the positioning support, in combination with the rotation-stopping unit, ensures the fixed relative position of the graphite bearing and the positioning support; and the guide grooves extend to the shaft part by a preset depth, thereby providing accurate cutting guidance and depth limitation for the saw blade.

Description

Technical Field

[0001] This application relates to the field of machining technology, and in particular to an apparatus for machining lubrication grooves in graphite bearings. Background Technology

[0002] The afterburning fuel system is not only a thrust multiplier for aero engines, but also a crucial guarantee for ensuring engine reliability and tactical flexibility under complex operating conditions. As the core control component of the engine's afterburning fuel system, the afterburning fuel flow regulator supplies high-pressure fuel to the afterburner to generate greater thrust; precisely controls fuel supply to ensure efficient combustion; rapidly responds to changes in thrust demand; and works in conjunction with other engine control systems to ensure safe and stable operation. The afterburning fuel flow regulator has a complex structure, containing a large number of high-speed rotating gear parts. Bearings are the foundation for the reliable operation of high-speed rotating parts, and graphite bearings are widely used in modern aero engines due to their simple structure and reliable operation.

[0003] To ensure the safe and reliable operation of the graphite bearing inside the afterburner fuel flow regulator, eight radial grooves for lubrication need to be machined on the end face of the graphite bearing. The groove width is 0.25 mm-0.76 mm, and the groove depth is 0.13 mm-0.5 mm. Previously, scribers and grooving tools were used to machine the lubrication grooves. However, due to the high brittleness and tendency to chip during graphite processing, graphite fragments and chipping easily occurred, causing the graphite bearing to fail, resulting in poor lubrication, bearing wear, and ultimately, malfunction of the afterburner fuel flow regulator. Furthermore, it was difficult to precisely machine the lubrication grooves of the specified width and depth on the graphite end face; only the even distribution of the eight lubrication grooves on the graphite bearing end face could be guaranteed.

[0004] Therefore, there is an urgent need for a dedicated device to solve problems such as positioning accuracy, guiding stability and operating efficiency in the machining of radial lubrication grooves on the end face of graphite bearings, so as to achieve high-precision, high-efficiency and high-consistency machining. Utility Model Content

[0005] This application provides an apparatus for processing lubrication grooves in graphite bearings, which can solve the technical problems of low positioning accuracy, poor guiding stability, and high scrap rate in the processing of radial lubrication grooves on the end face of graphite bearings in the prior art. The technical solution is as follows:

[0006] An apparatus for machining lubrication grooves in graphite bearings includes: a saw blade and a saw blade bracket for mounting the saw blade; a positioning support including a disc and a shaft coaxially disposed on one side of the disc; the disc having multiple radially extending guide grooves, the guide grooves penetrating the disc axially and extending to the shaft to a predetermined depth to guide the saw blade in cutting; and an anti-rotation unit disposed on the outer circumferential surface of the shaft, used to achieve circumferential positioning and radial interference fit between the shaft and the graphite bearing when the shaft is inserted into the inner hole of the graphite bearing.

[0007] Optionally, the anti-rotation unit is at least one annular rubber ring, and an annular groove adapted to the annular rubber ring is formed on the outer circumferential surface of the shaft, and the annular rubber ring is installed in the annular groove.

[0008] Optionally, the anti-rotation unit consists of multiple strip-shaped rubber strips arranged circumferentially along the shaft portion, and an axial groove adapted to the strip-shaped rubber strips is formed on the outer circumferential surface of the shaft portion, with the strip-shaped rubber strips installed in the axial grooves.

[0009] Optionally, the shaft portion has a threaded hole axially formed at the center of the end opposite to the disc portion, and a fastening bolt can be screwed into the threaded hole; the nut end face of the fastening bolt is used to abut against the end face of the graphite bearing to clamp the graphite bearing axially.

[0010] Optionally, the nut end face of the fastening bolt is provided with anti-slip texture.

[0011] Optionally, an anti-slip rubber pad is provided on the end face of the nut of the fastening bolt facing the disc.

[0012] Optionally, the number of guide grooves is eight, and they are evenly distributed along the circumference.

[0013] Optionally, the guide groove has a groove width of 0.7±0.05mm and the saw blade has a thickness of 0.6mm to accommodate lubrication grooves with a groove width of 0.25mm to 0.76mm.

[0014] Optionally, the guide groove extends to the shaft to a preset depth of 0.2 mm to 0.4 mm to accommodate the machining of lubrication grooves with a depth of 0.13 mm to 0.5 mm.

[0015] Optionally, a circular hole is provided at the center of the disc portion, the diameter of which is smaller than the diameter of the shaft portion, in order to reduce the contact area between the saw blade and the guide groove, thereby reducing the cutting resistance.

[0016] The beneficial effects of the technical solutions provided in this application include at least the following:

[0017] An apparatus for machining lubrication grooves in graphite bearings includes a saw blade and a saw blade support for mounting the saw blade, as well as a positioning support and an anti-rotation unit. The positioning support includes a disc and a shaft coaxially disposed on one side of the disc. The disc has multiple radially extending guide grooves that axially penetrate the disc and extend to a predetermined depth into the shaft to guide the saw blade during cutting. The anti-rotation unit is disposed on the outer circumferential surface of the shaft and is used to achieve circumferential positioning and radial interference fit between the shaft and the graphite bearing when the shaft is inserted into the inner hole of the graphite bearing. This apparatus for machining lubrication grooves in graphite bearings overcomes the shortcomings of traditional scribing machining methods through the collaborative design of multiple components. First, the combination of the saw blade and its support replaces traditional grooving tools. The rigid cutting edge of the saw blade, combined with the stable support of the blade support, reduces stress fluctuations during cutting, lowering the risk of chipping or breakage of the graphite material due to excessive local stress. Second, the coaxial design of the disc and shaft of the positioning support, combined with the circumferential positioning and radial interference fit of the anti-rotation unit, ensures the fixed relative position of the graphite bearing and the positioning support, avoiding the problem in traditional machining where "only eight grooves can be evenly distributed, but the width and depth of the grooves cannot be controlled." Finally, the guide groove's structure, "penetrating the disc and extending to a preset depth towards the shaft," provides precise cutting guidance and depth limitation for the saw blade, eliminating the need for additional measurements of the width and depth of the lubrication grooves after machining, greatly improving production efficiency. This device has a simple structure and low operating threshold, ensuring the machining accuracy of the lubrication grooves while reducing the scrap rate of graphite bearings.

[0018] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a 3D schematic diagram of a graphite bearing;

[0021] Figure 2 This is a schematic diagram of the saw blade and saw blade support in the apparatus for processing the lubrication groove of a graphite bearing provided in the embodiments of this application;

[0022] Figure 3 This is a three-dimensional schematic diagram of the apparatus for processing the lubrication groove of a graphite bearing provided in the embodiments of this application, with a graphite bearing clamped in place.

[0023] Figure 4 This is an exploded view of an apparatus for processing a lubrication groove in a graphite bearing and a graphite bearing, according to one embodiment of this application.

[0024] Figure 5 This is an exploded view of an apparatus for processing lubrication grooves in graphite bearings and a graphite bearing, according to another embodiment of this application.

[0025] Figure 6 This is a three-dimensional schematic diagram of a positioning support provided in an embodiment of this application;

[0026] Figure 7 This is a three-dimensional schematic diagram of another positioning support provided in an embodiment of this application;

[0027] Figure 8 This is a three-dimensional schematic diagram of the fastening bolt provided in the embodiments of this application.

[0028] Explanation of reference numerals in the attached figures

[0029] 1-Saw blade; 2-Saw blade bracket; 3-Positioning support; 31-Disc; 311-Guide groove; 312-Round hole; 32-Shaft; 321-Annular groove; 322-Axial groove; 323-Threaded hole; 4-Annular rubber ring; 5-Strip rubber strip; 6-Fasting bolt; 61-Anti-slip texture; 7-Anti-slip rubber pad; 8-Graphite bearing; 81-Lubrication groove. Detailed Implementation

[0030] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0031] In this disclosure, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the relative positions of the corresponding components in the direction of gravity when they are in use, and "inner" and "outer" refer to their relative positions to the contours of the corresponding components themselves. Furthermore, the terms "first," "second," etc., used in this disclosure are for distinguishing one element from another and do not have sequential or importance implications. In the following description, when referring to the accompanying drawings, unless otherwise explained, the same reference numerals in different drawings denote the same or similar elements.

[0032] refer to Figure 1 The graphite bearing 8 is cylindrical, and a radial lubrication groove 81 with uniform distribution needs to be machined on one end face.

[0033] According to the embodiments of this application, refer to Figures 2 to 8An apparatus for processing lubrication grooves in graphite bearings includes a saw blade 1 and a saw blade bracket 2 for mounting the saw blade 1, as well as a positioning support 3 and an anti-rotation unit. The positioning support 3 includes a disc portion 31 and a shaft portion 32 coaxially disposed on one side of the disc portion 31. The disc portion 31 has multiple radially extending guide grooves 311 that axially penetrate the disc portion 31 and extend to the shaft portion 32 to a predetermined depth, guiding the saw blade 1 for cutting. The anti-rotation unit is disposed on the outer circumferential surface of the shaft portion 32, used to achieve circumferential positioning and radial interference fit between the shaft portion 32 and the graphite bearing 8 when the shaft portion 32 is inserted into the inner hole of the graphite bearing 8.

[0034] When machining the lubrication groove 81 on the end face of the graphite bearing 8, first align the shaft portion 32 of the positioning support 3 with the inner hole of the graphite bearing 8 and slowly insert it into the inner hole. During this process, the anti-rotation unit on the outer circumference of the shaft portion 32 will gradually come into contact with the inner wall of the inner hole of the graphite bearing 8. Due to the elastic or frictional characteristics of the anti-rotation unit, it will form a tight fit with the inner wall of the inner hole through its own deformation or surface friction. On the one hand, it achieves a radial interference fit, preventing intermittent wobbling between the positioning support 3 and the graphite bearing 8 in the radial direction; on the other hand, it achieves circumferential positioning, avoiding relative rotation between the two during subsequent cutting, and ensuring that the machining position of each lubrication groove 81 corresponds completely with the guide groove 311. When the end face of the disc portion 31 is completely in contact with the end face of the lubrication groove 81 to be machined on the graphite bearing 8, the positioning and installation stage is completed. At this time, the graphite bearing 8 and the positioning support 3 form a stable whole, providing a reliable reference for cutting. Then, the cutting stage of the lubrication groove 81 begins. The operator holds the saw blade holder 2 with the saw blade 1 installed and aligns the cutting edge of the saw blade 1 with any of the radially extending guide grooves 311 on the disc 31, ensuring that the cutting edge of the saw blade 1 is fully embedded in the guide groove 311. The structure of the guide groove 311, which "penetrates the disc axially," guides the saw blade 1 to cut from the end face of the graphite bearing 8 towards the center, while the design of "extending to a preset depth towards the shaft" limits the cutting depth of the saw blade 1, preventing excessive cutting and damage to the graphite bearing 8. The operator slowly pushes the saw blade holder 2, causing the cutting edge of the saw blade 1 to cut along the trajectory of the guide groove 311 against the end face of the graphite bearing 8 until the cutting edge of the saw blade 1 reaches the preset depth position of the guide groove 311 extending towards the shaft 32. At this point, one lubrication groove 81 is completed. Following the same steps, the operator aligns the saw blade 1 with the other guide grooves 311 on the disc 31 and repeats the cutting action until all lubrication grooves 81 are completed.

[0035] This device for machining lubrication grooves in graphite bearings overcomes the shortcomings of traditional scriber machining methods through the collaborative design of multiple components. First, the combination of the saw blade 1 and the saw blade support 2 replaces the traditional grooving tool. The rigid cutting edge of the saw blade 1, combined with the stable support of the saw blade support 2, reduces force fluctuations during cutting, lowering the risk of graphite material chipping or breaking due to excessive localized stress. Second, the coaxial design of the disc portion 31 and the shaft portion 32 of the positioning support 3, combined with the circumferential positioning and radial interference fit of the anti-rotation unit, ensures the fixed relative position of the graphite bearing 8 and the positioning support 3, avoiding the problem in traditional machining where "only eight grooves can be evenly distributed, but the groove width and depth cannot be controlled." Finally, the structure of the guide groove 311, which "penetrates the disc portion 31 and extends to a preset depth towards the shaft portion 32," provides precise cutting guidance and depth limitation for the saw blade 1, eliminating the need for additional measurements of the width and depth of the lubrication groove 81 after machining, greatly improving production efficiency. Overall, the device has a simple structure and low operating threshold, which can ensure the machining accuracy of the lubrication groove 81 and reduce the scrap rate of the graphite bearing 8.

[0036] According to one embodiment of this application, reference is made to... Figure 4 and Figure 6 The anti-rotation unit is at least one annular rubber ring 4. An annular groove 321 adapted to the annular rubber ring 4 is opened on the outer circumferential surface of the shaft 32. The annular rubber ring 4 is installed in the annular groove 321 to realize the circumferential positioning and radial interference fit between the shaft 32 and the graphite bearing 8 when the shaft 32 is installed into the inner hole of the graphite bearing 8.

[0037] After the shaft portion 32 of the positioning support 3 is inserted into the inner hole of the graphite bearing 8, the portion of the annular rubber ring 4 protruding from the shaft portion 32 contacts the inner wall of the graphite bearing 8. Due to the elasticity of the annular rubber ring 4, it undergoes radial contraction deformation under contact pressure. This deformation causes the outer surface of the annular rubber ring 4 to tightly adhere to the inner wall of the graphite bearing 8, forming uniform radial pressure, thereby achieving a radial interference fit between the shaft portion 32 and the graphite bearing 8. Compared to a rigid anti-rotation structure, the elastic deformation of the annular rubber ring 4 prevents scratches or chipping of the graphite inner hole, protecting the integrity of the inner hole of the graphite bearing 8.

[0038] During the machining of the lubrication groove 81, the radially interference fit annular rubber ring 4 can ensure that the positioning support 3 will not be radially offset due to the cutting force of the saw blade 1. On the other hand, the circumferential static friction generated by the radially interference fit annular rubber ring 4 can prevent the graphite bearing 8 from rotating with the cutting action of the saw blade 1.

[0039] The annular rubber ring 4 is typically made of nitrile rubber or fluororubber, and its contact with the graphite inner hole is flexible. This solves the problem of traditional rigid positioning structures easily damaging the graphite inner hole, reducing the risk of scrapping the graphite bearing 8. Furthermore, the circumferential continuity of the annular rubber ring 4 makes its contact with the graphite bearing 8 inner hole more uniform. Compared to discontinuous anti-rotation structures, its circumferential positioning stability is superior, making it particularly suitable for machining scenarios requiring high uniformity of the eight lubrication grooves 81, further ensuring the lubrication uniformity of the graphite bearing 8.

[0040] According to another embodiment of this application, reference is made to Figure 5 and Figure 7 The anti-rotation unit consists of multiple strip-shaped rubber strips 5 arranged circumferentially along the shaft 32. An axial groove 322 adapted to the strip-shaped rubber strips 5 is opened on the outer circumferential surface of the shaft 32. The strip-shaped rubber strips 5 are installed in the axial groove 322 to achieve circumferential positioning and radial interference fit between the shaft 32 and the graphite bearing 8 when the shaft 32 is inserted into the inner hole of the graphite bearing 8.

[0041] The length of the axial groove 322 is the same as the length of the strip rubber strip 5, and the depth of the axial groove 322 is slightly less than the thickness of the strip rubber strip 5. After the strip rubber strip 5 is installed in the axial groove 322, the outer surface of the strip rubber strip 5 protrudes from the outer circumferential surface of the shaft portion 32. After the shaft portion 32 of the positioning support 3 is inserted into the inner hole of the graphite bearing 8, the parts of the multiple strip rubber strips 5 protruding from the shaft portion 32 will simultaneously contact the inner wall of the inner hole of the graphite bearing 8. Due to the elasticity of the strip rubber strip 5, it will contract radially under the action of contact pressure. This contraction makes the outer surface of each strip rubber strip 5 tightly fit the inner wall of the inner hole of the graphite bearing 8, forming a multi-point radial interference fit. Compared with the continuous contact of the annular rubber ring 4, the multi-point contact of the strip rubber strip 5 can more flexibly adapt to the small dimensional deviations of the inner hole of the graphite bearing 8. Even if there is a slight ellipticity in the inner hole of the graphite bearing 8, uniform fit can be achieved through the independent deformation of each strip rubber strip 5. The static friction of the multiple strip rubber strips 5 can prevent the positioning support 3 from rotating relative to the graphite bearing 8.

[0042] The axially extending structure of the strip-shaped rubber strip 5 increases its contact area with the inner hole of the graphite bearing 8, resulting in stronger static friction. Even under high cutting forces, it can maintain stable circumferential positioning and prevent slippage. In other embodiments, the anti-rotation unit can also use a combination of the above two forms, which is not limited in this application.

[0043] According to the embodiments of this application, refer to Figure 3 , Figure 7 and Figure 8 The shaft portion 32 has a threaded hole 323 axially opened at the center of one end away from the disc portion 31. A fastening bolt 6 can be screwed into the threaded hole 323. The nut end face of the fastening bolt 6 is used to abut against the end face of the graphite bearing 8 to clamp the graphite bearing 8 axially.

[0044] To address the axial movement issue of the graphite bearing 8, after the shaft portion 32 of the positioning support 3 is inserted into the inner hole of the graphite bearing 8, align the threaded end of the fastening bolt 6 with the threaded hole 323 at the end of the shaft portion 32 facing away from the disc portion 31, and slowly screw it in by hand until the nut end face of the fastening bolt 6 contacts the other end face of the graphite bearing 8. Ensure that the graphite bearing 8 is firmly clamped between the end face of the disc portion 31 and the nut end face of the fastening bolt 6, and that the clamping force is moderate. This ensures that the cutting depth of the saw blade 1 is always controlled by the preset depth extending from the guide groove 311 to the shaft portion 32, preventing the problem of "inconsistent depths in the same lubrication groove" caused by axial movement.

[0045] Axial clamping ensures that the fit between the end face of the graphite bearing 8 and the end face of the disc 31 remains consistent, preventing depth deviations in the lubrication groove 81 caused by axial movement and guaranteeing the depth tolerance of the machined lubrication groove 81. From an operational safety perspective, axial clamping reduces the risk of loosening of the graphite bearing 8 during cutting, preventing "blade chipping" or "operator hand injury" caused by sudden changes in force on the saw blade 1 due to bearing loosening. In terms of applicability, the adjustability of the fastening bolt 6 allows it to accommodate graphite bearings 8 of different heights.

[0046] According to the embodiments of this application, refer to Figure 8 The nut end face of the fastening bolt 6 is provided with anti-slip texture 61 to enhance the friction between the nut end face and the graphite bearing 8 end face and improve the reliability of axial clamping.

[0047] The anti-slip texture 61 design improves the reliability and stability of axial clamping. The anti-slip texture 61 effectively solves the problem of bolt loosening caused by cutting vibration or axial force on the end face of traditional smooth nuts, so that the clamping state of the fastening bolt 6 can be maintained until the machining is completed, reducing the rework rate caused by bolt loosening.

[0048] According to the embodiments of this application, refer to Figures 3 to 5 An anti-slip pad 7 is provided on the end face of the nut of the fastening bolt 6 facing the disc 31. The anti-slip pad 7 serves two purposes: firstly, it ensures hard contact between the graphite bearing 8 and the fastening bolt 6, thus protecting the graphite bearing 8; secondly, it increases the friction between the graphite bearing 8 and the fastening bolt 6, thereby preventing the graphite bearing 8 from rotating. The anti-slip pad 76 can be made of rubber.

[0049] According to the embodiments of this application, refer to Figure 3 and Figure 6The guide grooves 311 consist of eight grooves, evenly distributed circumferentially. From a lubrication performance perspective, the eight evenly distributed lubrication grooves 81 ensure uniform distribution of lubricating oil on the end face of the graphite bearing 8, preventing "insufficient lubrication in certain areas" or "localized lubricating oil accumulation" caused by uneven distribution of the lubrication grooves 81. From a processing efficiency perspective, the evenly distributed design of the eight guide grooves 311 eliminates the need to measure angles during processing; operators only need to align the guide grooves 311 in sequence. Compared to the traditional processing method of "measuring the angle after processing each groove," this improves processing efficiency, making it particularly suitable for batch processing scenarios.

[0050] According to an embodiment of this application, the guide groove 311 has a groove width of 0.7±0.05mm and the saw blade 1 has a thickness of 0.6mm. The guide groove 311 and the saw blade 1 are matched in size to accommodate the processing of lubrication grooves 81 with a groove width of 0.25mm to 0.76mm.

[0051] The dimensional fit between the guide groove 311 and the saw blade 1 enables precise control and flexible adaptation of the lubrication groove 81 width. In terms of precision control, traditional scribing machining can result in a groove width deviation of ±0.1mm, requiring measurement for each groove. However, this device, through the fit between the 0.7±0.05mm guide groove 311 and the 0.6mm saw blade 1, achieves a groove width deviation of only ±0.03mm, eliminating the need for measurement and significantly improving groove width accuracy and processing efficiency. In terms of versatility, the 0.7±0.05mm guide groove 311 can accommodate saw blades 1 with thicknesses ranging from 0.2mm to 0.7mm (the gap between the groove width and the saw blade thickness is maintained at 0.05mm-0.5mm, effectively limiting movement), thus processing lubrication grooves 81 ranging from 0.25mm to 0.76mm, covering the common size range of the lubrication groove 81 for graphite bearings 8. This eliminates the need for separately designed positioning supports 3 for different groove widths, reducing equipment costs. From the perspective of protecting the saw blade 1, the gap of 0.1mm-0.15mm avoids excessive friction between the saw blade 1 and the groove wall of the guide groove 311, thus extending the service life of the saw blade 1.

[0052] According to an embodiment of this application, the guide groove 311 extends to the shaft portion 32 at a preset depth of 0.2mm to 0.4mm. This extension depth limit allows for the processing of lubrication grooves 81 with a depth of 0.13mm to 0.5mm. The design of the extension depth of the guide groove 311 achieves "automatic control" of the depth of the lubrication groove 81, solving the problem of "difficulty in accurately controlling groove depth" in traditional processing. In terms of depth accuracy, the groove depth deviation of traditional grooving tools can reach ±0.08mm, and each groove needs to be measured. However, this device, through the extension depth limit of 0.2mm-0.4mm, achieves a groove depth deviation of only ±0.03mm, and requires no measurement, significantly improving depth accuracy and processing efficiency. From the perspective of preventing overcutting, the bottom of the extended portion of the guide groove 311 forms a "physical barrier," preventing the operator from excessively cutting the saw blade 1 due to excessive force, thereby damaging the graphite bearing 8. From the perspective of structural safety, the design of the guide groove 311 extending to the shaft portion 32 does not weaken the overall rigidity of the positioning support 3.

[0053] According to the embodiments of this application, refer to Figure 3 and Figure 6 A circular hole 312 is provided at the center of the disc portion 31, and the diameter of the circular hole 312 is smaller than the diameter of the shaft portion 32.

[0054] The circular hole 312 at the center of the disc 31 reduces the contact area, thereby lowering cutting resistance and improving operational convenience, while also solving the problem of chip accumulation. From the perspective of saw blade 1 lifespan, reduced resistance decreases stress damage to the saw blade 1, nearly doubling its lifespan and lowering consumable costs. Structurally, the diameter of the circular hole 312 is smaller than that of the shaft 32, ensuring no impact on the strength and positioning effect of the shaft 32. Furthermore, the simple machining process of the circular hole 312 does not significantly increase the manufacturing cost of the positioning support 3. In addition, the circular hole 312 reduces the overall weight of the positioning support 3, making the device lighter, easier to carry and operate, and particularly suitable for mobile processing needs in aviation maintenance sites, exhibiting high practicality and flexibility.

[0055] refer to Figure 1 and Figure 8 The working principle of the embodiments of this application is explained below with reference to the specific operation steps of machining the lubrication groove:

[0056] The following combination was selected as an example: "annular rubber ring as anti-rotation unit + fastening bolt (with anti-slip texture) + eight evenly distributed guide grooves + guide groove width 0.7±0.05mm + saw blade thickness 0.6mm + guide groove extension depth 0.2mm-0.4mm + central circular hole of the disc". The specific working process is as follows:

[0057] Step 1: Equipment Assembly Preparation

[0058] Saw blade and saw blade holder assembly: Select a saw blade with a thickness of 0.6mm, install it into the saw blade holder, check that the saw blade is not loose, and then set it aside for later use.

[0059] Assembly of the annular rubber ring and the positioning support: Select one annular rubber ring (made of nitrile rubber, Shore 70 hardness), and embed it into the annular groove on the outer circumference of the shaft of the positioning support. Ensure that the annular rubber ring is fully embedded and its outer surface protrudes 0.15mm from the outer circumference of the shaft. After checking that the annular rubber ring is not twisted, the anti-rotation unit assembly is completed.

[0060] Preparation of fastening bolts: Select fastening bolts with anti-slip texture (cross-grid pattern, depth 0.12mm), check that the threads are undamaged and the end face of the nut is flat, and set them aside for later use.

[0061] Step 2: Graphite bearing positioning and installation

[0062] Preliminary positioning: Align the shaft of the positioning support with the inner hole of the graphite bearing (the inner hole diameter of the graphite bearing is 0.1mm larger than the shaft diameter), and slowly insert it into the inner hole until the end face of the disc is completely in contact with one end face of the graphite bearing. At this time, the annular rubber ring forms a radial interference fit with the inner wall of the inner hole due to elastic deformation, achieving circumferential positioning and radial fixation without obvious shaking.

[0063] Axial clamping: Align the threaded end of the fastening bolt with the threaded hole at the end of the shaft away from the disc, and screw it in by hand until the end face of the nut contacts the other end face of the graphite bearing. Then, gently tighten it by 1 / 4 turn with a wrench to ensure that the graphite bearing is clamped between the disc and the end face of the nut, and that the clamping force is appropriate.

[0064] Step 3: Machining of the lubrication groove

[0065] Cutting sequence confirmation: Determine to process eight lubrication grooves in a clockwise order. With the positioning support shaft as the center, observe the eight evenly distributed guide grooves on the disc (adjacent included angle 45°, groove width 0.7mm, extension depth to the shaft 0.3mm), and mark the first guide groove to be processed.

[0066] Single groove cutting: Hold the saw blade holder with the saw blade installed, and insert the cutting edge of the saw blade into the first guide groove and another guide groove that is collinear with it, ensuring that the cutting edge is in contact with the groove wall. Slowly push the saw blade holder towards the center of the disc until it reaches the bottom of the guide groove extension depth (0.3mm). At this point, the saw blade can no longer cut, completing the machining of two radially collinear lubrication grooves (actual groove depth is about 0.32mm, and groove width is about 0.62mm). Then remove the saw blade.

[0067] Batch cutting: Rotate the saw blade support clockwise to align the saw blade edge with the next guide groove, and repeat the above cutting action to complete the processing of all lubrication grooves in sequence.

[0068] Step 4: Equipment disassembly and finished product inspection

[0069] To remove the fastening bolts: Use a wrench to loosen the fastening bolts in the opposite direction, and unscrew them completely from the threaded hole. Set aside for later use.

[0070] Disassembling the positioning support: Hold the disc of the positioning support with your hand and slowly pull out the shaft. Avoid pulling too hard, which may damage the graphite bearing or the annular rubber ring. After removing the positioning support, check that the annular rubber ring is not worn.

[0071] Finished product inspection: Observe the eight lubrication grooves on the end face of the graphite bearing to confirm that there are no missing pieces or chipped edges. Measure the included angle between adjacent grooves with an angle gauge to be 45°±0.3°, measure the groove depth with a depth gauge to be 0.32mm±0.02mm, and measure the groove width with a width gauge to be 0.62mm±0.02mm. All of these meet the requirements, and the processing is completed.

[0072] This embodiment achieves efficient and precise machining of the lubrication groove of the graphite bearing through multi-component collaboration. The machining efficiency is increased by 80% compared with the traditional method, and the scrap rate is reduced to less than 2%, which fully meets the machining requirements of graphite bearings for afterburner fuel flow regulators of aero engines.

[0073] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0074] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0075] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. An apparatus for processing lubrication grooves in graphite bearings, characterized in that, include: Saw blade (1) and saw blade bracket (2) for mounting said saw blade (1); The positioning support (3) includes a disc (31) and a shaft (32) coaxially disposed on one side of the disc (31); the disc (31) is provided with a plurality of radially extending guide grooves (311), the guide grooves (311) penetrating the disc (31) axially and extending to the shaft (32) to a predetermined depth, for guiding the saw blade (1) to cut; and, An anti-rotation unit is provided on the outer circumferential surface of the shaft (32) and is used to achieve circumferential positioning and radial interference fit between the shaft (32) and the graphite bearing (8) when the shaft (32) is installed into the inner hole of the graphite bearing (8).

2. The apparatus according to claim 1, characterized in that, The anti-rotation unit is at least one annular rubber ring (4), and an annular groove (321) adapted to the annular rubber ring (4) is provided on the outer peripheral surface of the shaft (32), and the annular rubber ring (4) is installed in the annular groove (321).

3. The apparatus according to claim 1, characterized in that, The anti-rotation unit consists of multiple strip-shaped rubber strips (5) arranged circumferentially along the shaft (32). An axial groove (322) adapted to the strip-shaped rubber strips (5) is provided on the outer circumferential surface of the shaft (32). The strip-shaped rubber strips (5) are installed in the axial groove (322).

4. The apparatus according to claim 1, characterized in that, The shaft (32) has a threaded hole (323) axially opened at the center of one end away from the disc (31), and a fastening bolt (6) can be screwed into the threaded hole (323); the nut end face of the fastening bolt (6) is used to abut against the end face of the graphite bearing (8) to clamp the graphite bearing (8) axially.

5. The apparatus according to claim 4, characterized in that, The nut end face of the fastening bolt (6) is provided with anti-slip texture (61).

6. The apparatus according to claim 4, characterized in that, The end face of the nut of the fastening bolt (6) facing the disc (31) is provided with an anti-slip rubber pad (7).

7. The apparatus according to claim 1, characterized in that, The number of guide grooves (311) is eight, and they are evenly distributed along the circumference.

8. The apparatus according to claim 1, characterized in that, The guide groove (311) has a groove width of 0.7±0.05mm and the saw blade (1) has a thickness of 0.6mm to accommodate lubrication grooves (81) with a groove width of 0.25mm to 0.76mm.

9. The apparatus according to claim 1, characterized in that, The guide groove (311) extends to the shaft portion (32) to a predetermined depth of 0.2 mm to 0.4 mm to accommodate the machining of a lubrication groove (81) with a groove depth of 0.13 mm to 0.5 mm.

10. The apparatus according to claim 1, characterized in that, The center of the disk portion (31) is provided with a circular hole (312), the diameter of which is smaller than the diameter of the shaft portion (32).

Images