Wave spring machining process

Abstract

The invention relates to a machining process of a wave spring, which comprises the following steps: S1, punching: punching a preliminary part of the wave spring, an excircle reserved allowance A and an inner hole reserved allowance B by adopting a punching machining mode; s2, heat treatment is conducted, specifically, a heat treatment clamp is designed according to the design theoretical size, the allowance A and the allowance B of the wave spring; carrying out aging treatment on the primary part of the wave spring with the heat treatment clamp; s3, linear cutting is conducted, specifically, the outer circle of the wave spring with the theoretical design size is obtained through linear cutting; designing a cutting clamp; the preliminary part of the wave spring obtained after the step S31 is installed in a cutting clamp; and cutting the inner hole of the primary part in the heat treatment clamp by adopting linear cutting, taking the axis of the upper positioning through hole in the cutting clamp as a positioning center during cutting, and cutting in the upper positioning through hole and the lower positioning through hole of the cutting clamp to obtain the wave spring inner hole with the theoretical design size.

Description

Technical Field

[0001] The present invention relates to the technical field of wave spring processing, and more particularly, to a processing technology for wave springs. Background Art

[0002] A wave spring is an elastic element applied in fields such as aerospace and precision machinery. For example, a wave spring installed in a graphite sealing device of an aeroengine, as an elastic element that plays a radial sealing role, the end face of the graphite ring is pressed against the wall surface of the outer ring under the action of the wave spring to form end face sealing. If the elastic force of the wave spring is too small, it cannot play a sealing role; if the elastic force is too large, it will cause an increase in the friction force between the graphite ring and the housing, affect the followability of the graphite ring and the shaft, cause abnormal wear, and thus lead to lubricating oil leakage and even cause engine shutdown accidents. If the dimensions do not meet the requirements, normal assembly cannot be carried out. Therefore, it is necessary to strictly control the working elastic force and dimensions of the wave spring to ensure the reliable operation of the graphite sealing device.

[0003] With the development of the national aeroengine industry, the models are rapidly iterated, and the requirements for sealing technology are getting higher and higher. Correspondingly, the working state elastic force and dimensional accuracy of the wave spring are also getting higher and higher. Taking Figure 1 the wave spring for a certain new type of engine shown as an example, it includes all the characteristics of wave spring parts: multiple wave peaks, high requirements for working elastic force, and high part precision. The outer diameter of this part needs to ensure the spring width is only the width-to-diameter ratio is 0.015, and at the same time, the opening width needs to be ensured to be 7.2 ± 0.1 mm. The existing traditional processing methods generally use punching and blanking to form and ensure the dimensions, and there are the following disadvantages:

[0004] 1. Difficult mold design: When using a punching die for processing, the forming process of the part includes three parts: cutting, bending, and stretching. Since the ratio of the bending curvature radius to the material thickness is large, the bending deformation is basically in the elastic deformation range, while the wave spring requires the material to have a large plastic deformation. To control the elastic deformation amount and obtain the required bending height, it is generally required to increase the forming height (i.e., preset springback amount) and increase the material stretching deformation degree to make the stress in the material thickness direction tend to be consistent, generate a large plastic deformation, and thus reduce the bending springback amount to form the required waveform. At this time, it is necessary to accurately calculate the springback amount. However, in actual processing, there are differences in part materials and processing conditions, and only through repeated tests can the mold design be corrected according to the processing results to meet the design size and elastic performance requirements.

[0005] 2. Difficult mold manufacturing: The outer diameter of the part needs to ensure the spring width is only The width-to-diameter ratio is 0.015. According to the design and manufacturing experience of the mold, the manufacturing tolerance is generally given as 10% of the part tolerance, that is, the required tolerance is 0.01 mm. And in order to ensure cutting and reduce the wear degree, the hardness of the punch and the female die reaches HRC58 - 62, which further increases the manufacturing difficulty and cost.

[0006] 3. The wave spring is processed by stamping. First, during the stamping process, the part has springback. The traditional processing method is to measure the height of the part after stamping to see if it meets the requirements. If it does not meet the requirements, a fitter needs to correct the height. Second, the part is placed in a furnace for heat treatment in a free state. Due to the release of processing stress and heating, the part will also deform. After heat treatment, the height of the part also needs to be checked. If it does not meet the requirements, a fitter still needs to correct it.

[0007] 4. It is difficult to process open-type wave springs and the dimensions cannot be guaranteed: When the part is an open-type wave spring, the traditional stamping process cannot be processed in one step, and the stamping process has a large processing force, and the part has uncontrollable deformation, so the dimensions cannot be guaranteed.

[0008] In summary, there are problems in processing wave spring parts by traditional processes, such as difficult height control, large processing difficulty, inability to meet the design requirements, and high processing costs. Summary of the Invention

[0009] In view of the above-mentioned disadvantages of the prior art, the technical problem to be solved by the present invention is to provide a processing technology for wave springs, which can reduce the die design difficulty, reduce the processing difficulty, and ensure the part dimension requirements.

[0010] To achieve the above object, the present invention provides a processing technology for wave springs. The theoretical design dimensions of the wave spring include the theoretical outer diameter D, the theoretical inner diameter d, and the theoretical height H. The processing technology includes the following steps:

[0011] S1. Stamping: Adopt the stamping processing method to punch out the preliminary part of the wave spring, and reserve a margin A for the outer circle and a margin B for the inner hole. The inner hole diameter of the obtained preliminary part is d - 2B, and the outer circle diameter is D + 2A;

[0012] S2. Heat treatment: According to the theoretical design dimensions of the wave spring, the margin A, and the margin B, design a heat treatment fixture. The heat treatment fixture includes an upper clamping plate and a lower clamping plate. The lower side of the upper clamping plate is provided with an upper forming surface, and the upper side of the lower clamping plate is provided with a lower forming surface. When the upper clamping plate and the lower clamping plate are closed, a clamping and forming cavity for accommodating and clamping the preliminary part of the wave spring can be formed between the upper forming surface and the lower forming surface. The shape and height of the clamping and forming cavity are the same as the theoretical design dimensions of the wave spring; Place the preliminary part of the wave spring into the clamping and forming cavity, fixedly connect the upper clamping plate and the lower clamping plate, and the upper and lower end faces of the preliminary part are respectively in contact with the upper forming surface and the lower forming surface;

[0013] S22. The heat treatment fixture and the preliminary parts of the wave spring are aged together to perform heat treatment for sizing.

[0014] S3. Wire cutting:

[0015] S31. Outer circle wire cutting: The outer circle of the preliminary parts of the wave spring after heat treatment sizing is cut by wire cutting to obtain the outer circle of the wave spring with the theoretically designed dimensions.

[0016] S32. According to the theoretically designed dimensions of the wave spring, allowance A and allowance B, a cutting fixture is designed, including an upper clamping block and a lower clamping block. The upper clamping block is provided with a cylindrical upper positioning through hole, and the bottom surface of the upper clamping block is provided with an upper clamping surface. The lower clamping block is provided with a cylindrical lower positioning through hole, the top surface of the lower clamping block is provided with a lower clamping surface and a lower positioning ring surface around the outer side of the lower clamping surface. The upper positioning through hole and the lower positioning through hole are coaxially arranged, and the diameters of the upper positioning through hole and the lower positioning through hole are both smaller than the theoretical inner diameter d of the wave spring; the shapes and sizes of the upper clamping surface and the lower clamping surface are the same as the theoretically designed shapes and sizes of the two end faces of the wave spring, and the diameter of the lower positioning ring surface is the same as the theoretical outer diameter D of the wave spring and is coaxially arranged with the upper positioning through hole.

[0017] S33. The preliminary parts of the wave spring after step S31 are installed on the lower clamping surface and kept in contact, and the outer circle of the preliminary parts is in contact with the lower positioning ring surface for positioning. The upper clamping surface of the upper clamping block is pressed against the upper end face of the preliminary parts of the wave spring, and the upper clamping block and the lower clamping block are fixedly connected.

[0018] S34. The inner hole of the preliminary parts of the wave spring in the heat treatment fixture is cut by wire cutting. During cutting, the axes of the upper positioning through hole and the lower positioning through hole are used as the positioning center, and cutting is performed in the upper positioning through hole and the lower positioning through hole to obtain the inner hole of the wave spring with the theoretically designed dimensions; finally, a formed wave spring part with the theoretically designed dimensions is obtained.

[0019] Further, in the step S1, the allowance A is 0.02D - 0.03D.

[0020] Further, in the step S1, the allowance B is 0.02d - 0.03d.

[0021] Further, the theoretical outer diameter D of the wave spring is 125 mm, the theoretical inner diameter d is 120.6 mm. In the step S1, the outer diameter of the preliminary parts of the wave spring obtained is 132 mm, and the inner diameter is 116 mm.

[0022] Further, the cutting fixture further includes a locking connection mechanism connecting the upper clamping block and the lower clamping block. The locking connection mechanism includes a connecting stud and a compression nut. The lower end of the connecting stud is connected to the lower clamping block, and the upper end thereof passes through a connection through-hole in the upper clamping block. The compression nut is screwed onto the connecting stud and can be pressed against the upper end face of the upper clamping block.

[0023] Further, there are a plurality of the locking connection mechanisms, which are evenly distributed annularly around the central axis of the upper positioning through-hole.

[0024] Further, the cutting fixture further includes a crimping plate and a fixing bolt. An outer edge plate is provided on the outer periphery of the lower clamping block. The crimping plate is arranged on the upper end of the outer edge plate. The fixing bolt passes through the crimping plate and the outer edge plate and is used for screwing into a wire cutting machine to fix the lower clamping block to the wire cutting machine.

[0025] Further, the wave spring has an opening. In step S32, fixture notches are also provided in both the upper clamping block and the lower clamping block. In step S33, the position where the opening needs to be machined during the preliminary part installation of the wave spring is located in the fixture notch; in step S34, after the inner hole cutting is completed, wire cutting is performed in the fixture notch to machine the opening.

[0026] Further, it further includes: S4. Deburr the formed parts and conduct a resilience durability experiment.

[0027] As described above, the processing technology involved in the present invention has the following beneficial effects:

[0028] The processing process includes three stages: punching, heat treatment, and wire cutting. In the preliminary punching stage, machining allowances for the inner hole and the outer circle are reserved, and the height of the part does not need to be strictly controlled. Instead, the height control is completed in the heat treatment stage, and the machining of the inner hole and the outer circle is completed through the wire cutting stage. In this way, the punching stage is simple in processing, has low requirements for the punching die, does not need to consider springback, and can well reduce the difficulty of die manufacturing; in the heat treatment stage, the parts are clamped by a heat treatment fixture and aged together, which can well control the height of the parts, the working resilience meets the design requirements, has high consistency, and reduces the fitter correction work; in the wire cutting stage, when cutting the inner hole, it is completed on the cutting fixture. Even when the radial width of the part is extremely narrow, it is not easy to deform, the product has high consistency, and wire cutting can complete precision dimension machining; in particular, it can be well used for accelerating the production of a wave spring with an extremely narrow radial width and an opening. Description of the Drawings

[0029] Figure 1 It is a top view of the wave spring with the designed theoretical dimensions in the present invention.

[0030] Figure 2 It is Figure 1 a side view of

[0031] Figure 3 This is the top view of the preliminary part of the corrugated spring obtained by punching in the present invention.

[0032] Figure 4 This is the structural schematic diagram of the heat treatment fixture in the present invention.

[0033] Figure 5 This is the side view of the preliminary part of the corrugated spring after heat treatment in the present invention.

[0034] Figure 6 This is the structural schematic diagram of the cutting fixture in the present invention.

[0035] Figure 7 is Figure 6 the sectional view taken along the E-E direction in

[0036] Figure 8 The flow chart of the processing technology of the corrugated spring of the present invention

[0037] Explanation of the reference numerals in the attached drawings

[0038] 1 Corrugated spring

[0039] 11 Opening

[0040] 2 Heat treatment fixture

[0041] 21 Upper clamping plate

[0042] 211 Upper forming surface

[0043] 22 Lower clamping plate

[0044] 221 Lower forming surface

[0045] 23 Part installation area

[0046] 24 Connecting bolt

[0047] 25 Connecting nut

[0048] 3 Cutting fixture

[0049] 31 Upper clamping block

[0050] 311 Upper positioning through hole

[0051] 312 Upper clamping surface

[0052] 32 Lower clamping block

[0053] 321 Lower positioning through hole

[0054] 322 Lower clamping surface

[0055] 33 Connecting stud

[0056] 34 Connecting pin

[0057] 35 Compression nut

[0058] 36 Crimping plate

[0059] 37 Fixing bolt

[0060] 38 Fixture notch Detailed implementation mode

[0061] The following specific embodiments illustrate the implementation mode of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0062] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Usually, the components of the embodiments of the present invention described and shown in the accompanying drawings here can be arranged and designed in various different configurations.

[0063] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed during use. 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 cannot be understood as a limitation to the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive distinction and cannot be understood as indicating or implying relative importance.

[0064] In the description of the present invention, it should also be noted that unless otherwise clearly specified and limited, the terms "set", "installed", "connected", "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 situations.

[0065] As Figures 1 to 8 shown, the present invention provides a processing technology for a wave spring. The designed theoretical dimensions of the wave spring 1 include the theoretical outer diameter D, the theoretical inner diameter d, and the theoretical height H, and the following steps are included:

[0066] S1. Stamping:

[0067] Adopt a stamping process to punch out the preliminary parts of the corrugated spring 1, and leave a margin A for the outer diameter and a margin B for the inner hole. The inner hole diameter of the preliminary parts of the corrugated spring 1 obtained is d - 2B, and the outer diameter is D + 2A, where the margin A is preferably 0.02D to 0.03D, and the margin B is preferably 0.02d to 0.03d.

[0068] See Figure 1 and Figure 2 , taking the corrugated spring 1 shown as an example, where the theoretical outer diameter D of the corrugated spring 1 is 125.2 mm, the theoretical inner diameter d is 120.6 mm, then the theoretical radial width W is 2.3 mm, and the theoretical height H is 3.7 mm. During stamping, the margin A is preferably 3.4 mm, and the margin B is preferably 2.3 mm. Then the outer diameter of the preliminary parts of the corrugated spring 1 obtained is 132 mm, the inner hole diameter is 116 mm, and the radial width is 8 mm. Compared with the theoretical dimensions, the ratio of the radial width to the outer diameter of the preliminary parts of the corrugated spring 1 increases from 0.015 mm in the design theoretical dimensions to 0.0606 mm, and the tolerance can also be increased from 0.1 mm to 0.4 mm. The parts with margins after improvement are processed in subsequent steps.

[0069] In this step, when using a stamping die for stamping, there is no need to strictly consider the height dimension of the corrugated spring 1. At the same time, there are margins for both the outer diameter and the inner hole. Therefore, when designing the stamping die, there is no need to design it strictly according to the design theoretical dimensions of the corrugated spring 1, nor to consider the elastic recovery that will occur to the preliminary parts of the corrugated spring 1 during stamping. Therefore, the design difficulty and cost of the stamping die can be greatly reduced.

[0070] S2. Heat treatment:

[0071] Design a heat treatment fixture 2 according to the design theoretical dimensions of the corrugated spring 1, the margin A, and the margin B. See Figure 4, the heat treatment fixture 2 includes an upper clamping plate 21 and a lower clamping plate 22. An upper forming surface 211 is provided on the lower side of the upper clamping plate 21, and a lower forming surface 221 is provided on the upper side of the lower clamping plate 22. The shapes of the upper forming surface 211 and the lower forming surface 221 are designed according to the theoretical shape dimensions of both end faces of the wave spring 1. Between the upper forming surface 211 and the lower forming surface 221 is a part installation area 23. When the upper clamping plate 21 and the lower clamping plate 22 are closed, a clamping and forming cavity for accommodating the preliminary part of the wave spring 1 can be formed between the upper forming surface 211 and the lower forming surface 221. The shape and height of the obtained clamping and forming cavity are the same as the design theoretical dimensions of the wave spring 1. At the same time, the inner diameter of the clamping and forming cavity is less than or equal to d - 2B, and the outer diameter is greater than or equal to D + 2A, so that the preliminary part of the wave spring 1 can be well placed; after the preliminary part of the wave spring 1 is deburred by a fitter, it is placed into the clamping and forming cavity. The upper clamping plate 21 and the lower clamping plate 22 are fixedly connected, and the upper and lower end faces of the preliminary part of the wave spring 1 are respectively attached to the upper forming surface 211 and the lower forming surface 221.

[0072] In this embodiment, preferably, refer to Figure 4 , the heat treatment fixture 2 further includes a connecting bolt 24 and a connecting nut 25. The lower end of the connecting bolt 24 passes through the through hole in the upper clamping plate 21 and is fixedly connected in the lower clamping plate 22. The connecting nut 25 is screwed on the connecting bolt 24 and is located on the upper side of the upper clamping plate 21. After the connecting bolt 24 is rotated upward, the upper clamping plate 21 can move up and down along the connecting bolt 24, separating from or closing with the lower clamping plate 22. A circumferential positioning structure can be provided between the upper clamping plate 21 and the lower clamping plate 22 to ensure that the upper forming surface 211 and the lower forming surface 221 are accurately aligned and matched when the two are closed. During use, the preliminary part of the wave spring 1 is placed on the lower forming surface 221 and kept in contact. Then the upper clamping plate 21 descends along the connecting bolt 24 until the upper forming surface 211 is pressed against and attached to the upper end face of the preliminary part of the wave spring 1. Then the connecting nut 25 is screwed on and tightened on the upper end face of the upper clamping plate 21 to ensure that the upper clamping plate 21 and the lower clamping plate 22 are fixedly connected well and the preliminary part of the wave spring 1 is clamped.

[0073] S22. The heat treatment fixture 2 and the preliminary part of the wave spring 1 are subjected to aging treatment together for heat treatment and shaping. To ensure that the part has stable physical properties of the metal material, aging treatment is required. Aging treatment is a metal heat treatment process. The main principle is that during the heating and cooling process of the metal or alloy, its internal structure changes, so that the material can obtain the required mechanical properties and physical properties. During the aging treatment process, since the preliminary part of the wave spring 1 is always located in the heat treatment fixture 2, its height and shape are limited by the clamping and forming cavity. After aging treatment, the preliminary part of the wave spring 1 can accurately obtain the theoretical design height. Refer to Figure 5 as shown, the part can obtain stable height and working elastic force.

[0074] S3. Wire cutting:

[0075] S31. Outer circle wire cutting: The outer circle of the preliminary part of the corrugated spring 1 after heat treatment shaping is cut by wire cutting to obtain the outer circle of the corrugated spring 1 with the theoretically designed dimensions.

[0076] In this application, wire cutting is short for electrical discharge wire cutting, which is a processing method of removing metal by pulsed spark discharge. It has high processing accuracy, generally reaching 0.01 mm, and can also cut multiple workpieces with high cutting efficiency. When processing the outer circle by wire cutting, since the radial width dimension of the preliminary part of the corrugated spring 1 is still relatively large and not prone to deformation, the outer circle can be processed by existing conventional methods, and ordinary fixtures can be used to fix the preliminary part during cutting.

[0077] S32. According to the theoretically designed dimensions, allowance A and allowance B of the corrugated spring 1, a cutting fixture 3 is designed, including an upper clamping block 31 and a lower clamping block 32. The upper clamping block 31 is provided with a cylindrical upper positioning through hole 311, and the bottom surface of the upper clamping block 31 is provided with an upper clamping surface 312. The lower clamping block 32 is provided with a cylindrical lower positioning through hole 321, the top surface of the lower clamping block 32 is provided with a lower clamping surface 322 and a lower positioning ring surface (not shown in the drawing) around the outer side of the lower clamping surface 322. The lower clamping surface 322 and the lower positioning ring surface form a groove structure for accommodating the preliminary part of the corrugated spring 1. The upper positioning through hole 311 and the lower positioning through hole 321 are coaxially arranged, and the diameters of the upper positioning through hole 311 and the lower positioning through hole 321 are both smaller than the theoretical inner diameter d of the corrugated spring 1. The shapes and dimensions of the upper clamping surface 312 and the lower clamping surface 322 are the same as the theoretically designed shapes and dimensions of the two end faces of the corrugated spring 1. The diameter of the lower positioning ring surface is the same as the theoretical outer diameter D of the corrugated spring 1 and is coaxially arranged with the upper positioning through hole 311. In this embodiment, when there is an opening 11 on the corrugated spring 1, both the upper clamping block 31 and the lower clamping block 32 are also provided with fixture notches 38. The size of the fixture notches 38 can be set according to specific needs. The fixture notches 38 preferably extend from the top surface of the upper clamping block 31 straight down to the bottom surface and then extend downward a certain height from the top surface of the lower clamping block 32. The inner side of the fixture notches 38 communicates with the upper positioning through hole 311 and the lower positioning through hole 321.

[0078] In this embodiment, refer to Figure 6 and Figure 7, as an optimal design, the cutting fixture 3 further includes a locking connection mechanism connecting the upper clamping block 31 and the lower clamping block 32. The locking connection mechanism includes a connecting stud 33 and a compression nut 35. The lower end of the connecting stud 33 is connected to the lower clamping block 32 through a connecting pin 34, and the upper end passes through the connecting through hole in the upper clamping block 31. The compression nut 35 is screwed on the connecting stud 33 and can be pressed against the upper end face of the upper clamping block 31. Preferably, there are multiple locking connection mechanisms, such as three or more, and they are evenly distributed annularly around the central axis of the upper positioning through hole 311 to ensure that the upper clamping block 31 and the lower clamping block 32 can be evenly and stably connected, so as to stably clamp the preliminary parts of the corrugated spring 1, and can also position the circumferential angle between the upper clamping block 31 and the lower clamping block 32. An outer edge plate is provided on the outer periphery of the lower clamping block 32, and the pressing plate 36 is arranged at the upper end of the outer edge plate. The lower clamping block 32 is fixed to the wire cutting machine by passing a fixing bolt 37 through the pressing plate 36 and the outer edge plate and screwing it into the wire cutting machine, which is convenient for assembly during processing.

[0079] S33. Install the preliminary parts of the corrugated spring 1 after step S31 on the lower clamping surface 322 and keep them in contact, and position the outer circle of the preliminary parts in contact with the lower positioning ring surface. At this time, the central axis of the preliminary parts also coincides with the central axis of the lower positioning through hole 321; since the diameters of the upper positioning through hole 311 and the lower positioning through hole 321 are both smaller than the theoretical inner diameter d of the corrugated spring 1, the inner hole of the preliminary parts of the corrugated spring 1 extends into the upper positioning through hole 311 and the lower positioning through hole 321, and at the same time, the position where the opening 11 needs to be processed on the preliminary parts is located in the fixture notch 38 of the lower clamping block 32; press the upper clamping surface 312 of the upper clamping block 31 against the upper end face of the preliminary parts of the corrugated spring 1, and align the fixture notch 38 in the upper clamping block 31 with the fixture notch 38 in the lower clamping block 32; then fix and connect the upper clamping block 31 and the lower clamping block 32 through three locking connection mechanisms, so as to clamp and fix the preliminary parts of the corrugated spring 1 evenly and stably, and ensure that the position where the opening 11 needs to be processed on the preliminary parts is located in the fixture notch 38.

[0080] S33. Use wire cutting to cut the inner hole of the preliminary parts of the corrugated spring 1 in the heat treatment fixture 2. During cutting, use the axes of the upper positioning through hole 311 and the lower positioning through hole 321 as the positioning center and perform cutting in the upper positioning through hole 311 and the lower positioning through hole 321 to obtain the inner hole of the corrugated spring 1 with the theoretical design size. Although the radial width of the preliminary parts is very small during the gradual cutting of the inner hole, because it is stably clamped in the heat treatment fixture 2, there will be no deformation problem. When the corrugated spring 1 still has an opening 11, after the inner hole cutting is completed, wire cutting is performed in the fixture notch 38 to process the opening 11.

[0081] After the wire cutting step, the formed parts of the corrugated spring 1 are obtained, meeting the requirements of the design theoretical size.

[0082] S4. Deburr the formed wave spring 1 parts and conduct a spring force durability test to check the working spring force and durability. Then, after inspection, including full dimensional inspection and appearance inspection, it is packaged after cleaning.

[0083] The processing technology of the present invention has the following beneficial effects:

[0084] The processing process includes three stages: punching, heat treatment, and wire cutting. In the initial punching stage, machining allowances for the inner hole and outer circle are reserved, and the height of the part does not need to be strictly controlled. Instead, the height control is completed in the heat treatment stage, and the machining of the inner hole and outer circle is completed through the wire cutting stage. In this way, the punching stage has simple processing, low requirements for the punching die, no need to consider springback, and can well reduce the difficulty of die manufacturing; in the heat treatment stage, the parts are clamped by the heat treatment fixture 2 and aged together, which can well control the height of the parts, the working spring force meets the design requirements, has high consistency, and reduces the fitter correction work; in the wire cutting stage, the inner hole cutting is completed on the cutting fixture 3, and the part is not prone to deformation even when the radial width is extremely narrow, the product has high consistency, and precision dimensional machining can be completed by wire cutting; in particular, it can be well used to accelerate the production of wave springs 1 with extremely narrow radial widths and openings 11.

[0085] In summary, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0086] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A processing technology for a wave spring, wherein the wave spring (1) has a theoretical design dimension including a theoretical outer diameter D, a theoretical inner diameter d and a theoretical height H, and is characterized in that: The processing technology comprises the following steps: S1. Punching: Punching out the preliminary part of the wave spring (1) by punching, and leaving a margin A for the outer circle and a margin B for the inner hole. The inner hole diameter of the preliminary part is d-2B, and the outer circle diameter is D+2A. S2. Heat treatment: according to the theoretical design dimensions, allowance A and allowance B of the wave spring (1), a heat treatment fixture (2) is designed. The heat treatment fixture (2) comprises an upper clamping plate (21) and a lower clamping plate (22). An upper molding surface (211) is provided on the lower side of the upper clamping plate (21), and a lower molding surface (221) is provided on the upper side of the lower clamping plate (22). When the upper clamping plate (21) and the lower clamping plate (22) are closed, a clamping molding cavity for accommodating the preliminary parts of the wave spring (1) can be formed between the upper molding surface (211) and the lower molding surface (221). The shape and height of the clamping molding cavity are the same as the theoretical design dimensions of the wave spring (1). The preliminary parts of the wave spring (1) are placed in the clamping molding cavity. The upper clamping plate (21) and the lower clamping plate (22) are fixedly connected. The upper and lower end surfaces of the preliminary parts are respectively in contact with the upper molding surface (211) and the lower molding surface (221). S22, the heat treatment fixture (2) carries out aging treatment with the preliminary parts of the wave spring (1), and heat treatment is performed to finalize the shape; S3, wire cutting: S31, outer circle wire cutting: the preliminary parts of the wave spring (1) after heat treatment and finalization are cut into outer circle by wire cutting to obtain the outer circle of the wave spring (1) of theoretical design size; S32. According to the theoretical dimensions, allowance A and allowance B of the wave spring (1), a cutting fixture (3) is designed, comprising an upper clamping block (31) and a lower clamping block (32), wherein the upper clamping block (31) is provided with a cylindrical upper positioning through hole (311), and the bottom surface of the upper clamping block (31) is provided with an upper clamping surface (312), the lower clamping block (32) is provided with a cylindrical lower positioning through hole (321), the top surface of the lower clamping block (32) is provided with a lower clamping surface (322), and a lower clamping surface (322) is provided around the outer side of the lower clamping surface (322). The upper positioning through hole (311) and the lower positioning through hole (321) are coaxially arranged, and the diameters of the upper positioning through hole (311) and the lower positioning through hole (321) are both smaller than the theoretical inner diameter d of the wave spring (1); the shape and size of the upper clamping surface (312) and the lower clamping surface (322) are the same as the theoretical design shape and size of the two end surfaces of the wave spring (1); the diameter of the lower positioning annular surface is the same as the theoretical outer diameter D of the wave spring (1), and is coaxial with the upper positioning through hole (311); S33, installing the preliminary part of the wave spring (1) after step S31 on the lower clamping surface (322) and keeping it in close contact, and the outer circle of the preliminary part is in contact with the lower positioning ring surface for positioning, and the upper clamping surface (312) of the upper clamping block (31) is pressed against the upper end surface of the preliminary part of the wave spring (1), and the upper clamping block (31) and the lower clamping block (32) are fixedly connected; S34, using wire cutting to cut the inner hole of the preliminary part of the wave spring (1) in the heat treatment fixture (2), using the axis of the upper positioning through hole (311) and the lower positioning through hole (321) as the positioning center during cutting, and cutting is performed in the upper positioning through hole (311) and the lower positioning through hole (321) to obtain the inner hole of the wave spring (1) with the theoretical design size; finally, a formed wave spring (1) part with the designed theoretical size is obtained.

2. The processing technology according to claim 1, characterized in that: In the step S1, the margin A is 0.02D to 0.03D.

3. The processing technology according to claim 1, characterized in that: In the step S1, the remainder B is 0.02d to 0.03d.

4. The processing technology according to claim 1, characterized in that: The theoretical outer diameter D of the wave spring (1) is 125 mm, and the theoretical inner diameter d is 120.6 mm. In the step S1, the outer diameter of the preliminary part of the wave spring (1) obtained is 132 mm, and the inner diameter is 116 mm.

5. The processing technology according to claim 1, characterized in that: The cutting clamp (3) also includes a locking connection mechanism connecting the upper clamp block (31) and the lower clamp block (32), and the locking connection mechanism includes a connecting stud (33) and a clamping nut (35). The lower end of the connecting stud (33) is connected to the lower clamp block (32), and the upper end passes through the connecting through hole in the upper clamp block (31). The clamping nut (35) is screwed on the connecting stud (33) and can be pressed on the upper end surface of the upper clamp block (31).

6. The processing technology according to claim 5, characterized in that: There are multiple locking connection mechanisms, which are evenly distributed in a ring shape around the central axis of the upper positioning through hole (311).

7. The processing technology according to claim 5, characterized in that: The cutting fixture (3) further comprises a crimping plate (36) and a fixing bolt (37); an outer edge plate is provided on the outer periphery of the lower clamping block (32); the crimping plate (36) is arranged at the upper end of the outer edge plate; the fixing bolt (37) passes through the crimping plate (36) and the outer edge plate and is used for being screwed into the wire cutting machine to fix the lower clamping block (32) to the wire cutting machine.

8. The processing technology according to claim 1, characterized in that: The wave spring (1) has an opening (11). In the step S32, a clamp notch (38) is also provided in the upper clamp block (31) and the lower clamp block (32). In the step S33, the position of the opening (11) needs to be processed in the clamp notch (38) when the preliminary parts of the wave spring (1) are installed. In the step S34, after the inner hole cutting is completed, wire cutting is performed in the clamp notch (38) to obtain the opening (11).

9. The processing technology according to claim 1, characterized in that: Also includes: S4. Deburr the formed parts and conduct elastic force durability test.

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