A method of machining a diamond gear

Abstract

The application provides a processing method of a diamond gear, and belongs to the technical field of mechanical processing. The method solves the problem of poor precision of the diamond gear produced by the existing method. The processing method comprises the following steps: A, brushing graphite glue on the tooth profile surface of an outer gear mold core to form a conductive layer and loading the conductive layer into a pouring mold; B, pouring a molten liquid formed by mixing metal material and epoxy resin into the pouring mold, and combining the molten liquid with the conductive layer to form a negative mold after solidification; C, pushing the outer gear mold core to separate the outer gear mold core from the negative mold, and sequentially electroplating a thin nickel layer, electroplating diamond grit and a thick nickel layer on the inner tooth profile of the negative mold; D, peeling off the support layer and the conductive layer, taking the metal core to keep concentric with the thick nickel layer, pouring a molten liquid formed by mixing metal material and epoxy resin between the metal core and the thick nickel layer, and forming the diamond gear after solidification. The diamond gear processed by the method has consistent exposed height of the diamond grit on the tooth profile surface after the thin nickel layer is ground, has high precision and good modification effect.

Description

Technical Field

[0001] This invention belongs to the field of machining technology and relates to a method for machining diamond gears. Background Technology

[0002] Diamond gears are high-precision shaping tools with a layer of superhard abrasive grains (diamond micro powder, also known as diamond abrasive) coated on the helical tooth surface of gears. They have the same geometric parameters as the workpiece being processed and can be used to shape gear processing tools such as grinding wheels, honing wheels, and gear shaving cutters. They have advantages such as high precision in shaping the profile, strong forming ability, fast shaping speed, high efficiency, simple operation, long service life, and ensuring the stability of shape, precision, and roughness of batch-processed parts.

[0003] Compared to the smooth outer circumference of diamond rollers, diamond gears have complex helical tooth profiles. Therefore, the existing processing of diamond gears mainly adopts the external plating method, that is, firstly, a gear base with helical teeth is formed, and then a layer of diamond micro powder (carborundum) is electroplated on the tooth profile surface of the gear base, which is commonly known as sanding. For example, the sanding device for diamond gear processing disclosed in Chinese patent application (application number: 201911158680.9) describes the processing technology of diamond gears: the gear is fixed on a fixed mechanism connected to a drive motor, so that the gear is immersed in a plating solution containing diamond micro powder. The drive motor is started, and the rotation of the drive motor drives the gear to rotate through the fixed mechanism. The rotation of the gear can drive the plating solution to flow, so that the diamond micro powder is evenly dispersed in the plating solution. Then, electricity is turned on, and under the action of direct current, the diamond micro powder is evenly electroplated on the gear to complete the sanding and form a diamond gear.

[0004] Although the above processing technology can coat the tooth profile surface of diamond gears with a layer of diamond grit, the edge effect of the electric field and the large size dispersion of the diamond grit during the coating process will result in inconsistent exposed height of the coated diamond grit on the surface. This leads to poor manufacturing precision of the diamond gears and affects the shaping effect during use.

[0005] To improve the manufacturing precision of diamond gears, the current conventional practice is to use larger electrodes or multiple electrodes to minimize the impact of the edge effect of the battery. Summary of the Invention

[0006] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing a method for processing diamond gears. The technical problem to be solved by this invention is: how to solve the problem of poor precision in diamond gears produced by existing processing methods.

[0007] The objective of this invention can be achieved through the following technical solution: a method for machining diamond gears, characterized in that the method includes the following steps:

[0008] A. Apply graphite adhesive to the tooth profile surface of the external gear mold core to form a conductive layer. After the conductive layer solidifies, install the external gear mold core into the mold cavity of the casting mold.

[0009] B. A molten liquid made of a mixture of metal materials and epoxy resin is poured into the mold cavity of the casting mold to form a support layer. After the support layer solidifies, it is combined with the conductive layer to form a female mold.

[0010] C. Push the external gear mold core to separate it from the female mold, electroplat a thin nickel layer onto the inner tooth profile of the female mold, then electroplat diamond on the thin nickel layer, and then electroplat a thick nickel layer on the diamond.

[0011] D. Cut open the support layer, peel off the support layer and the conductive layer, take out the columnar metal core with a central hole, pass the metal core through the thick nickel layer and keep it concentric with the thick nickel layer, pour the molten liquid formed by the mixture of metal material and epoxy resin between the metal core and the thick nickel layer to form a bonding layer, and form a diamond gear after solidification.

[0012] This method employs an internal plating process to machine diamond gears. First, a female mold is cast, with its inner tooth profile matching the outer tooth profile of the diamond gear. Then, a thin nickel layer, a diamond grit layer, and a thick nickel layer are electroplated onto the inner tooth profile of the mold, with the diamond grit layered between the thin and thick nickel layers. The mold is then removed, leaving a composite of the thin nickel layer, diamond grit, and thick nickel layer that matches the tooth profile of the diamond gear to be machined. This composite is then cast and fixed onto a metal core to form the diamond gear. During use, the thin nickel layer is ground away, exposing the diamond grit. In diamond gears machined using this method, the diamond grit is electroplated onto a thin nickel layer. The uniform thickness and even plating ability of nickel ensure that all the diamond grit remains on the same reference surface. This guarantees a consistent height of exposed diamond grit on the tooth profile surface after the thin nickel layer is ground away, resulting in high precision and a better shaping effect for the entire diamond gear.

[0013] Graphite is malleable and easily broken. Therefore, to facilitate subsequent crushing and peeling, the female mold processed using the internal plating method is generally formed by pressing graphite powder. Thus, in conventional understanding within this field, the internal plating method is generally suitable for processing diamond rollers with relatively regular structures. This is because for complex structures like diamond gears with helical tooth profiles, the tooth profile strength of the female mold formed by pressing graphite powder cannot meet the fitting requirements with the external gear mold core, making it impossible to smoothly demold the external gear mold core. This processing method overcomes the aforementioned conventional technical bias and improves and innovates the processing method of the female mold. The entire female mold is made of two different materials: a conductive layer and a support layer. The conductive layer formed by graphite adhesive is only a thin layer applied to the tooth profile surface of the external gear mold core, serving to isolate the external gear mold core from the cast support layer, maintaining a clear boundary between the two and facilitating subsequent peeling of the female mold. The main body of the female mold consists of a support layer, which is formed by mixing metal materials and epoxy resin. The metal material ensures that the tooth profile formed by the female mold has sufficient hardness and strength and will not deform under stress. The addition of epoxy resin allows the support layer to better bond with the conductive layer, forming a tight physical bond. This allows the female mold to be pushed outward by simply pressing it against the thrust bearing when removing the external gear mold core. Under the action of the thrust bearing, the female mold rotates, allowing the external gear mold core to smoothly exit the female mold along the tooth profile. Moreover, the nickel plating layer of this application is divided into a thin nickel layer and a thick nickel layer. The thin nickel layer is relatively easy to grind off and can be used as a reference surface to ensure the accuracy of the diamond grit, while the thick nickel layer has high chemical stability and good wear resistance, and can be used as a wear-resistant plating layer and an intermediate connecting layer.

[0014] In the aforementioned diamond gear processing method, in step A, before brushing on the graphite adhesive to form a conductive layer, the external gear mold core is first cleaned. Then, a release agent is sprayed onto the surface of the external gear mold core, and it is smoothed with a silk cloth sprayed with the release agent. Cleaning the external gear mold core prevents impurities from adhering to the tooth profile surface, which could affect the accuracy of the inner tooth profile of the mold. Simultaneously, spraying the release agent onto the surface of the external gear mold core makes the outer tooth profile surface smoother, easier to separate from the conductive layer, and prevents them from sticking together, facilitating subsequent demolding of the external gear mold core from the mold. Wiping with a silk cloth sprayed with the release agent further smooths the outer tooth profile surface, ensures a more even distribution of the release agent, and the silk itself is fine and smooth, preventing scratches or lint on the tooth profile surface.

[0015] In the aforementioned diamond gear processing method, in step A, the brushed graphite adhesive is formed by mixing graphite powder and epoxy resin, with a mass ratio of graphite powder to epoxy resin of 4:1 to 2:1. The thickness of the formed conductive layer is 0.2 to 0.5 mm, and the curing time is 18 to 30 hours. If the conductive layer is too thick, it is prone to local deformation under stress during the demolding process of the external gear mold core, affecting the accuracy of the tooth profile inside the female mold. If the conductive layer is too thin, it is easy for the support layer of the female mold to stick to the external gear mold core during the casting process, affecting the demolding of the external gear mold core. Maintaining the conductive layer within the range specified in this application yields the best results. Maintaining the mass ratio of graphite powder to epoxy resin within the aforementioned range ensures both easy subsequent peeling and adhesion between the conductive layer and the support layer, while also providing sufficient toughness.

[0016] In the above-described diamond gear processing method, in step B, the mass ratio of metal material to epoxy resin is 7:2 to 2:1. After casting, it is first cured at room temperature for 18 to 30 hours, and then left to stand for 2 to 4 days. Preferably, the metal material is iron powder. Curing the support layer at room temperature for 18 to 30 hours after casting, followed by standing, optimizes the overall performance (adhesion, shrinkage, mechanical properties, chemical stability, and dimensional stability).

[0017] In the above-described diamond gear processing method, in step B, after the female mold is solidified and formed, the two end faces of the female mold are precision machined using the external gear mold core as a reference to achieve a flatness of 0.02–0.04 mm. Precision machining of the two end faces of the female mold using the external gear mold core as a reference ensures the accuracy of the produced female mold, thereby guaranteeing the precision of the subsequently formed diamond gear.

[0018] Preferably, in the above-described diamond gear processing method, in step C, the thickness of the thin nickel layer is 0.01–0.015 mm, and the thickness of the thick nickel layer is 2–2.5 mm. Maintaining the thickness of the thin nickel layer within this range facilitates the plating of diamond abrasive onto the die and serves as a reference surface to ensure the accuracy of the diamond abrasive, while also being relatively easy to grind off. Maintaining the thickness of the thick nickel layer within this range allows for complete coverage of the diamond abrasive, exhibiting high chemical stability and good wear resistance, and can be used as a wear-resistant plating layer and intermediate connecting layer.

[0019] In the above-described diamond gear processing method, in step C, after electroplating to form a thick nickel layer, the ends of both the thin and thick nickel layers are precision machined to achieve a flatness of 0.02–0.04 mm. This process further ensures the precision of the subsequently formed diamond gear.

[0020] In the above-described diamond gear processing method, in step D, the metal core is a steel core, the metal material is steel, and the mass ratio of the steel material to epoxy resin is 7:2 to 5:2. Using the same casting material as the metal core ensures good integrity of the formed diamond gear and maintains consistent performance.

[0021] In the aforementioned diamond gear manufacturing method, in step D, the inner hole of the solidified diamond gear is precision machined, and the concentricity of the precision-machined diamond gear is checked. Precision machining of the inner hole ensures a high degree of concentricity between the inner hole and the outer tooth profile, further guaranteeing the manufacturing accuracy of the diamond gear. The concentricity is checked using a universal tool microscope to align and verify the diamond gear; if the deviation is significant, further adjustments are made to ensure manufacturing accuracy.

[0022] In the above-described diamond gear machining method, step D further includes inspecting the tooth accuracy of the diamond gear. This inspection further ensures manufacturing precision.

[0023] Compared with existing technologies, this method for machining diamond gears has the following advantages:

[0024] The diamond grit is electroplated on a thin nickel layer. Nickel has a uniform thickness and good plating ability, so all the diamond grit can be kept on the same reference surface. This ensures that after the thin nickel layer is ground away, the exposed height of the diamond grit on the tooth profile surface is consistent, resulting in high precision of the entire diamond gear and a better shaping effect. Attached Figure Description

[0025] Figure 1 This is a three-dimensional structural diagram of the external gear mold core.

[0026] Figure 2 This is a cross-sectional schematic diagram of the tooth profile surface of the external gear mold core after a conductive layer has been formed by brushing.

[0027] Figure 3 This is a cross-sectional view of the external gear mold core after it has been cast to form a female mold.

[0028] Figure 4 This is a cross-sectional view of the female mold after the external gear mold core has been removed.

[0029] Figure 5 This is a cross-sectional schematic diagram showing the electroplating of a thin nickel layer, a diamond layer, and a thick nickel layer on the inner tooth profile surface of the female mold.

[0030] Figure 6 yes Figure 5 A cross-sectional view after the female mold has been removed.

[0031] Figure 7This is a cross-sectional view of the diamond gear produced by the machining process.

[0032] In the diagram, 1 is the external gear mold core; 2 is the conductive layer; 3 is the support layer; 4 is the thin nickel layer; 5 is the corundum; 6 is the thick nickel layer; 7 is the metal core; and 8 is the connecting layer. Detailed Implementation

[0033] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0034] Example 1

[0035] The machining method for this diamond gear includes the following steps:

[0036] A. Select a helical gear with the same dimensions and other parameters as the diamond gear to be processed as the external gear mold core 1. Clean the external gear mold core 1 thoroughly, then spray a release agent onto its surface and smooth it with a silk cloth sprayed with the release agent. Figure 1 As shown.

[0037] Then, graphite adhesive is brushed onto the tooth profile surface of the external gear mold core 1. The graphite adhesive is formed by mixing graphite powder and epoxy resin, with a mass ratio of graphite powder to epoxy resin of 4:1. The thickness of the conductive layer 2 formed is 0.2 mm. After brushing, the graphite adhesive is left to solidify for 18 hours to form the conductive layer 2. Figure 2 As shown. Then, the external gear mold core 1 is installed into the mold cavity of the casting mold.

[0038] B. A molten liquid mixture of metal powder and epoxy resin is poured into the mold cavity. The metal powder is iron powder, and the mass ratio of metal powder to epoxy resin is 7:2. After pouring, it is first cured at room temperature for 18 hours to form a support layer 3, which then bonds with the conductive layer 2 to form a negative mold. It is then left to stand for 2 days to allow its performance to reach its optimal level. Figure 3 As shown.

[0039] Then open the end plates of the casting mold, and using the external gear mold core 1 as a reference, perform precision machining on the end faces of the female mold using a lathe to make its flatness reach 0.02mm.

[0040] C. Transfer the female mold, external gear mold core 1, and the casting mold with both end caps removed to the spiral synchronous demolding mechanism. This allows one end face of the female mold to press against the thrust bearing. The ejector rod of the press pushes the external gear mold core 1, causing the thrust bearing to rotate. The external gear mold core 1, through the engagement of its helical teeth with the female mold, withdraws from the female mold, achieving separation. Figure 4 As shown.

[0041] First, a thin nickel layer 4 with a thickness of 0.01 mm is electroplated onto the inner tooth profile of the female mold. Then, diamond abrasive 5 is electroplated onto the thin nickel layer 4. Next, a thick nickel layer 6 with a thickness of 2 mm is electroplated onto the diamond abrasive 5. Finally, the ends of the thin nickel layer 4 and the thick nickel layer 6 are precision machined to achieve a flatness of 0.02 mm. Figure 5 As shown.

[0042] D. Remove the female mold and saw open the support layer 3. Peel off the support layer 3 and the conductive layer 2, leaving a toothed structure composed of a thin nickel layer 4, diamond abrasive 5, and a thick nickel layer 6. Figure 6 As shown. A columnar metal core 7 with a central hole is taken. The aforementioned tooth-shaped structure is fitted over the metal core 7, ensuring concentricity. A molten liquid mixture of metal material and epoxy resin is poured between the metal core 7 and the thick nickel layer 6 to form a bonding layer 8. After solidification, a diamond gear is formed. The metal core 7 is a steel core, and the metal material is steel. The mass ratio of steel material to epoxy resin is 7:2. Figure 7 As shown.

[0043] The inner hole of the solidified diamond gear is precision machined, and the diamond gear is aligned using a universal tool microscope to check if the concentricity meets the requirements. If the deviation is large, it is adjusted further. Then, the tooth accuracy of the diamond gear is checked to see if it meets the requirements. If it does not meet the requirements, the tooth accuracy is adjusted. If it does meet the requirements, the machining is completed.

[0044] This method employs an internal casting process to machine diamond gears, overcoming conventional technical biases and innovating the processing method of the female mold. The entire female mold is made of two different materials: a conductive layer 2 and a support layer 3. The conductive layer 2, formed by graphite adhesive, is only a thin layer applied to the tooth profile surface of the external gear mold core 1, serving to isolate the external gear mold core 1 from the cast support layer 3, maintaining a clear boundary between the two and facilitating subsequent mold removal. The main body of the female mold consists of the support layer 3, which is formed by a mixture of metal and epoxy resin. The metal material ensures that the tooth profile formed by the female mold has sufficient hardness and strength, preventing deformation under stress. The addition of epoxy resin allows the support layer 3 to better bond with the conductive layer 2, forming a tight physical bond. This allows the female mold to be easily removed when the external gear mold core 1 is ejected; simply place the female mold against the thrust bearing and push the external gear mold core 1 outwards. Under the action of the thrust bearing, the female mold rotates, allowing the external gear mold core 1 to smoothly exit the female mold along the tooth profile. Furthermore, the nickel plating layer of this application is divided into a thin nickel layer 4 and a thick nickel layer 6. The thick nickel layer 6 has high chemical stability and good wear resistance, and can be used as a wear-resistant plating layer and an intermediate connecting layer. The diamond abrasive 5 is electroplated on the thin nickel layer 4. The uniform thickness and even plating ability of nickel are good, which can ensure that all the diamond abrasive 5 are kept on the same reference surface. The thin nickel layer 4 is relatively easy to grind away. As a reference surface, it can ensure that the exposed height of the diamond abrasive 5 on the tooth profile surface is consistent after the thin nickel layer 4 is ground away. The overall precision of the diamond gear is high, thus having a better shaping effect.

[0045] Example 2

[0046] The machining method for this diamond gear includes the following steps:

[0047] A. Take a helical gear with the same dimensions and other parameters as the diamond gear to be processed as the external gear mold core 1. Clean the external gear mold core 1, then spray a release agent on the surface of the external gear mold core 1 and smooth it with a silk cloth sprayed with the release agent.

[0048] Then, graphite adhesive is brushed onto the tooth profile surface of the external gear mold core 1. The graphite adhesive is formed by mixing graphite powder and epoxy resin, with a mass ratio of graphite powder to epoxy resin of 3:1. The thickness of the conductive layer 2 formed is 0.35mm. After brushing, the graphite adhesive is left to solidify for 24 hours to form the conductive layer 2. Then, the external gear mold core 1 is installed into the mold cavity of the casting mold.

[0049] B. A molten liquid formed by mixing metal material and epoxy resin is poured into the mold cavity of the casting mold. The metal material is iron powder, and the mass ratio of metal material to epoxy resin is 3:1. After pouring, it is first cured at room temperature for 24 hours to form a support layer 3, which is then combined with the conductive layer 2 to form a negative mold. Then it is left to stand for 3 days to allow its performance to reach the best.

[0050] Then open the end plates of the casting mold, and using the external gear mold core 1 as a reference, perform precision machining on the end faces of the female mold using a lathe to make its flatness reach 0.03mm.

[0051] C. Transfer the female mold, the external gear mold core 1, and the casting mold with the end caps removed to the spiral synchronous demolding mechanism. This allows one end face of the female mold to press against the thrust bearing. The external gear mold core 1 is pushed by the ejector rod of the press. The thrust bearing is forced to rotate the female mold. The external gear mold core 1 is then separated from the female mold by the helical gear engagement between the external gear mold core 1 and the female mold.

[0052] First, a thin nickel layer 4 with a thickness of 0.012 mm is electroplated onto the inner tooth profile of the female mold. Then, diamond abrasive 5 is electroplated onto the thin nickel layer 4. Next, a thick nickel layer 6 with a thickness of 2.2 mm is electroplated onto the diamond abrasive 5. Then, the ends of the thin nickel layer 4 and the thick nickel layer 6 are precision machined to make their flatness reach 0.03 mm.

[0053] D. Remove the negative mold and saw open the support layer 3. Peel off the support layer 3 and the conductive layer 2, leaving a tooth-shaped structure composed of a thin nickel layer 4, diamond abrasive 5, and a thick nickel layer 6. Take a columnar metal core 7 with a central hole, and fit the tooth-shaped structure over the metal core 7, keeping them concentric. Pour a molten liquid formed by mixing metal material and epoxy resin between the metal core 7 and the thick nickel layer 6 to form a bonding layer 8. After solidification, a diamond gear is formed. The metal core 7 is a steel core, and the metal material is steel. The mass ratio of steel material to epoxy resin is 3:1.

[0054] The inner hole of the solidified diamond gear is precision machined, and the diamond gear is aligned using a universal tool microscope to check if the concentricity meets the requirements. If the deviation is large, it is adjusted further. Then, the tooth accuracy of the diamond gear is checked to see if it meets the requirements. If it does not meet the requirements, the tooth accuracy is adjusted. If it does meet the requirements, the machining is completed.

[0055] This method employs an internal casting process to machine diamond gears, overcoming conventional technical biases and innovating the processing method of the female mold. The entire female mold is made of two different materials: a conductive layer 2 and a support layer 3. The conductive layer 2, formed by graphite adhesive, is only a thin layer applied to the tooth profile surface of the external gear mold core 1, serving to isolate the external gear mold core 1 from the cast support layer 3, maintaining a clear boundary between the two and facilitating subsequent mold removal. The main body of the female mold consists of the support layer 3, which is formed by a mixture of metal and epoxy resin. The metal material ensures that the tooth profile formed by the female mold has sufficient hardness and strength, preventing deformation under stress. The addition of epoxy resin allows the support layer 3 to better bond with the conductive layer 2, forming a tight physical bond. This allows the female mold to be easily removed when the external gear mold core 1 is ejected; simply place the female mold against the thrust bearing and push the external gear mold core 1 outwards. Under the action of the thrust bearing, the female mold rotates, allowing the external gear mold core 1 to smoothly exit the female mold along the tooth profile. Furthermore, the nickel plating layer of this application is divided into a thin nickel layer 4 and a thick nickel layer 6. The thick nickel layer 6 has high chemical stability and good wear resistance, and can be used as a wear-resistant plating layer and an intermediate connecting layer. The diamond abrasive 5 is electroplated on the thin nickel layer 4. The uniform thickness and even plating ability of nickel are good, which can ensure that all the diamond abrasive 5 are kept on the same reference surface. The thin nickel layer 4 is relatively easy to grind away. As a reference surface, it can ensure that the exposed height of the diamond abrasive 5 on the tooth profile surface is consistent after the thin nickel layer 4 is ground away. The overall precision of the diamond gear is high, thus having a better shaping effect.

[0056] Example 3

[0057] The machining method for this diamond gear includes the following steps:

[0058] A. Take a helical gear with the same dimensions and other parameters as the diamond gear to be processed as the external gear mold core 1. Clean the external gear mold core 1, then spray a release agent on the surface of the external gear mold core 1 and smooth it with a silk cloth sprayed with the release agent.

[0059] Then, graphite adhesive is brushed onto the tooth profile surface of the external gear mold core 1. The graphite adhesive is formed by mixing graphite powder and epoxy resin, with a mass ratio of graphite powder to epoxy resin of 2:1. The thickness of the conductive layer 2 formed is 0.5 mm. After brushing, the graphite adhesive is left to solidify for 30 hours to form the conductive layer 2. Then, the external gear mold core 1 is installed into the mold cavity of the casting mold.

[0060] B. A molten liquid formed by mixing metal materials and epoxy resin is poured into the mold cavity of the casting mold. The metal material is steel powder, and the mass ratio of metal material to epoxy resin is 2:1. After pouring, it is first cured at room temperature for 30 hours to form a support layer 3, which is then combined with the conductive layer 2 to form a negative mold. Then it is left to stand for 4 days to allow its performance to reach the best.

[0061] Then open the end plates of the casting mold, and using the external gear mold core 1 as a reference, perform precision machining on the end faces of the female mold using a lathe to make its flatness reach 0.04mm.

[0062] C. Transfer the female mold, the external gear mold core 1, and the casting mold with the end caps removed to the spiral synchronous demolding mechanism. This allows one end face of the female mold to press against the thrust bearing. The external gear mold core 1 is pushed by the ejector rod of the press. The thrust bearing is forced to rotate the female mold. The external gear mold core 1 is then separated from the female mold by the helical gear engagement between the external gear mold core 1 and the female mold.

[0063] First, a thin nickel layer 4 with a thickness of 0.015 mm is electroplated onto the inner tooth profile of the female mold. Then, diamond abrasive 5 is electroplated onto the thin nickel layer 4. Next, a thick nickel layer 6 with a thickness of 2.5 mm is electroplated onto the diamond abrasive 5. Then, the ends of the thin nickel layer 4 and the thick nickel layer 6 are precision machined to make their flatness reach 0.04 mm.

[0064] D. Remove the negative mold and saw open the support layer 3. Peel off the support layer 3 and the conductive layer 2, leaving a tooth-shaped structure composed of a thin nickel layer 4, diamond abrasive 5, and a thick nickel layer 6. Take a columnar metal core 7 with a central hole, and fit the tooth-shaped structure over the metal core 7, keeping them concentric. Pour a molten liquid formed by mixing metal material and epoxy resin between the metal core 7 and the thick nickel layer 6 to form a bonding layer 8. After solidification, a diamond gear is formed. The metal core 7 is a steel core, and the metal material is steel. The mass ratio of steel material to epoxy resin is 5:2.

[0065] The inner hole of the solidified diamond gear is precision machined, and the diamond gear is aligned using a universal tool microscope to check if the concentricity meets the requirements. If the deviation is large, it is adjusted further. Then, the tooth accuracy of the diamond gear is checked to see if it meets the requirements. If it does not meet the requirements, the tooth accuracy is adjusted. If it does meet the requirements, the machining is completed.

[0066] This method employs an internal casting process to machine diamond gears, overcoming conventional technical biases and innovating the processing method of the female mold. The entire female mold is made of two different materials: a conductive layer 2 and a support layer 3. The conductive layer 2, formed by graphite adhesive, is only a thin layer applied to the tooth profile surface of the external gear mold core 1, serving to isolate the external gear mold core 1 from the cast support layer 3, maintaining a clear boundary between the two and facilitating subsequent mold removal. The main body of the female mold consists of the support layer 3, which is formed by a mixture of metal and epoxy resin. The metal material ensures that the tooth profile formed by the female mold has sufficient hardness and strength, preventing deformation under stress. The addition of epoxy resin allows the support layer 3 to better bond with the conductive layer 2, forming a tight physical bond. This allows the female mold to be easily removed when the external gear mold core 1 is ejected; simply place the female mold against the thrust bearing and push the external gear mold core 1 outwards. Under the action of the thrust bearing, the female mold rotates, allowing the external gear mold core 1 to smoothly exit the female mold along the tooth profile. Furthermore, the nickel plating layer of this application is divided into a thin nickel layer 4 and a thick nickel layer 6. The thick nickel layer 6 has high chemical stability and good wear resistance, and can be used as a wear-resistant plating layer and an intermediate connecting layer. The diamond abrasive 5 is electroplated on the thin nickel layer 4. The uniform thickness and even plating ability of nickel are good, which can ensure that all the diamond abrasive 5 are kept on the same reference surface. The thin nickel layer 4 is relatively easy to grind away. As a reference surface, it can ensure that the exposed height of the diamond abrasive 5 on the tooth profile surface is consistent after the thin nickel layer 4 is ground away. The overall precision of the diamond gear is high, thus having a better shaping effect.

[0067] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

[0068] Although this document frequently uses terms such as external gear mold core 1, conductive layer 2, support layer 3, thin nickel layer 4, diamond 5, thick nickel layer 6, metal core 7, and connecting layer 8, the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of the invention; interpreting them as any additional limitation would contradict the spirit of the invention.

Claims

1. A method for machining diamond gears, characterized in that, The method includes the following steps: A. Apply graphite adhesive to the tooth profile surface of the external gear mold core (1) to form a conductive layer (2). After the conductive layer (2) solidifies, install the external gear mold core (1) into the mold cavity of the casting mold. B. A molten liquid made of a mixture of metal material and epoxy resin is poured into the mold cavity of the casting mold to form a support layer (3). After the support layer (3) is cured, it is combined with the conductive layer (2) to form a female mold. C. Push the external gear mold core (1) to separate it from the female mold, electroplate a thin nickel layer (4) onto the inner tooth profile of the female mold, then electroplate diamond (5) onto the thin nickel layer (4), and then electroplate a thick nickel layer (6) onto the diamond (5); the thickness of the thin nickel layer (4) is 0.01 to 0.015 mm, and the thickness of the thick nickel layer (6) is 2 to 2.5 mm; D. Cut open the support layer (3), peel off the support layer (3) and the conductive layer (2), take out the columnar metal core (7) with a central hole, pass the metal core (7) through the thick nickel layer (6) and keep it concentric with the thick nickel layer (6), pour the molten liquid formed by the mixture of metal material and epoxy resin between the metal core (7) and the thick nickel layer (6) to form a bonding layer (8), and form a diamond gear after solidification.

2. The method for machining diamond gears according to claim 1, characterized in that, In step A, before brushing graphite adhesive to form a conductive layer (2), the external gear mold core (1) is cleaned, and then a release agent is sprayed onto the surface of the external gear mold core (1) and smoothed with a silk cloth sprayed with the release agent.

3. The method for machining diamond gears according to claim 1 or 2, characterized in that, In step A, the graphite adhesive applied by brushing is formed by mixing graphite powder and epoxy resin. The mass ratio of graphite powder to epoxy resin is 4:1 to 2:

1. The thickness of the conductive layer (2) formed is 0.2 to 0.5 mm, and the solidification time is 18 to 30 h.

4. The method for machining diamond gears according to claim 1 or 2, characterized in that, In step B, the mass ratio of metal material to epoxy resin is 7:2 to 2:

1. After casting, it is first cured at room temperature for 18 to 30 hours, and then left to stand for 2 to 4 days.

5. The method for machining diamond gears according to claim 1 or 2, characterized in that, In step B, after the female mold is solidified and formed, the two end faces of the female mold are precision machined based on the external gear mold core (1) to make its flatness reach 0.02 to 0.04 mm.

6. The method for machining diamond gears according to claim 1 or 2, characterized in that, In step C, after electroplating to form a thick nickel layer (6), the ends of the thin nickel layer (4) and the thick nickel layer (6) are finely processed to achieve a flatness of 0.02 to 0.04 mm.

7. The method for machining diamond gears according to claim 1 or 2, characterized in that, In step D, the metal core (7) is a steel core, the metal material is steel, and the mass ratio of the steel material to the epoxy resin is 7:2 to 5:

2.

8. The method for machining diamond gears according to claim 7, characterized in that, In step D, the inner hole of the solidified diamond gear is precision machined, and the concentricity of the precision-machined diamond gear is tested.

9. The method for machining diamond gears according to claim 7, characterized in that, In step D, the tooth accuracy of the diamond gear is also tested.

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