Commutator carbon sheet film making process

Abstract

The present invention relates to a commutator carbon sheet film making process, comprising the following steps: S1: providing an SLM workbench, a main lifting platform, an auxiliary lifting platform, a scraper, a first powder, a high-energy beam emitter and a substrate, and adding the first powder to the main lifting platform in the powder tank; S2: placing the commutator carbon sheet in the carbon sheet tank, and using the auxiliary lifting platform to lift the substrate to a position where the top surface of the commutator carbon sheet coincides with the working surface of the SLM workbench; S3: using the auxiliary lifting platform to lower the height of the substrate, the lowering distance is the required coating thickness, and using the main lifting platform to lift the first powder in the powder tank, so that the first powder is pushed above the working surface of the SLM workbench; S4: using a scraper to slide on the working surface of the SLM workbench, and pushing the first powder on the powder tank to the substrate in the processing tank; S5: the high-energy beam emitter irradiates the first powder located above the commutator carbon sheet. The present invention provides a commutator carbon sheet film making process with a copper shell and a carbon sheet more firmly connected and a substrate used in the process.

Description

Technical Field

[0001] The invention relates to the technical field of commutators, and in particular to a commutator carbon sheet film making process. Background Art

[0002] The commutator is a key component that allows the motor to rotate continuously. The commutator consists of a welded shell and a carbon sheet. At present, the shell is mainly made of copper. The main component of the carbon sheet is carbon. Carbon and copper cannot be dissolved in each other, nor can they form intermetallic compounds, and are difficult to combine. In other words, it is difficult to weld the carbon sheet and the copper shell.

[0003] In the existing technology, a metal layer, such as copper or nickel, is often plated on the carbon surface by chemical means, and then the film-forming surface and the copper shell are bonded together by brazing to form a commutator.

[0004] The commutator formed by chemically connecting the copper shell and the carbon sheet has insufficient bonding force, which greatly shortens the service life of the commutator and cannot meet people's usage needs. Summary of the invention

[0005] In summary, in order to overcome the deficiencies of the prior art, the present invention provides a commutator carbon sheet film making process in which the copper shell and the carbon sheet are more firmly connected.

[0006] To achieve the above object, the present invention provides the following technical solution: a substrate, comprising a substrate body, a carbon sheet groove is provided on one end surface of the substrate body, and the diameter of the carbon sheet groove is not less than the outer diameter of the commutator carbon sheet.

[0007] With this arrangement, the commutator carbon segments can be placed in the carbon segment slots during processing, and then the substrate body with the commutator carbon segments is placed in the SLM device for processing and coating. Several carbon segment slots can be set as needed, so that multiple commutator carbon segments can be coated at one time.

[0008] Furthermore, a positioning column is provided on the bottom surface of the carbon segment groove, the diameter of the positioning column is adapted to the inner diameter of the commutator carbon segment, and the diameter of the carbon segment groove is larger than the outer diameter of the commutator carbon segment.

[0009] With this arrangement, the diameter of the carbon sheet groove is larger than the outer diameter of the commutator carbon sheet. After the commutator carbon sheet is placed in, a gap will be formed between the inner wall of the carbon sheet groove and the outer wall of the commutator carbon sheet, which is convenient for removing the carbon sheet after film formation. The diameter difference between the two can be set to 3-4mm. After setting the positioning column, the commutator carbon sheet can be sleeved on the positioning column to fix its position, avoid sliding in the carbon sheet groove and cause dislocation of the SLM equipment coating, and prevent the commutator carbon sheet from contacting the inner wall of the carbon sheet groove, so as to avoid the commutator carbon sheet and the carbon sheet groove from sticking together after the metal powder melts during the processing, thereby damaging the substrate body.

[0010] Furthermore, the height of the positioning column is lower than the thickness of the commutator carbon segment.

[0011] With this arrangement, the top surface of the positioning column will be lower than the top surface of the commutator carbon segment that needs to be plated, which can prevent the commutator carbon segment and the positioning column from sticking together after the metal powder melts during processing and damaging the substrate body. The height difference between the two can be set to 0.5-1mm.

[0012] Furthermore, the substrate body is provided with a sealing groove surrounding its side wall.

[0013] With such arrangement, a sealing ring can be sleeved in the sealing groove of the side wall of the substrate to prevent powder from falling.

[0014] A commutator carbon sheet film making process comprises the following steps:

[0015] S1: Provide an SLM workbench, a main lifting platform, a secondary lifting platform, a scraper, a first powder, a high-energy beam emitter, and a substrate as described in any one of claims 1 to 4, wherein the SLM workbench is provided with a powder tank and a processing tank, the main lifting platform is adapted to the powder tank, the substrate is adapted to the processing tank, the substrate is located on the top of the secondary lifting platform, the carbon sheet tank is located on the top of the substrate, and the first powder is added to the main lifting platform in the powder tank;

[0016] S2: Place the commutator carbon segment into the carbon segment slot, and use the auxiliary lifting platform to lift the base plate to a position where the top surface of the commutator carbon segment overlaps with the working surface of the SLM workbench;

[0017] S3: Use the auxiliary lifting platform to lower the height of the substrate to the required coating thickness, and use the main lifting platform to lift the first powder in the powder tank so that the first powder is pushed above the working surface of the SLM workbench;

[0018] S4: Use a scraper to slide on the working surface of the SLM worktable to push the first powder on the powder tank to the top of the substrate in the processing tank;

[0019] S5: The high energy beam emitter irradiates the first powder located above the commutator carbon segment.

[0020] With this arrangement, the high-energy beam emitter will scan the bed of the first powder layer by layer according to the path planned in the three-dimensional CAD slice model. The scanned first powder will be melted and solidified to achieve a metallurgical bonding effect, and finally the metal parts designed by the model will be obtained. The metal coating obtained in this way has stronger adhesion, the commutator is more durable, and the service life is longer.

[0021] Further, a second powder is provided, and after step S5, the second powder is added to the powder tank, and the substrate is lifted by the auxiliary lifting platform to a position where the top surface of the commutator carbon segment coated with the first powder overlaps with the working surface of the SLM workbench, and then steps S3-S5 are performed again.

[0022] With such arrangement, the material of the first powder can be selected from materials that have affinity for carbon and also for the second powder. In this way, the first powder can be used as an intermediate transition layer to connect the coating of the second powder and the commutator carbon sheet. The metal coating thus obtained has stronger adhesion, and the commutator is more durable and has a longer service life. The first powder in the powder tank can be cleaned and replaced with the second powder, or an SLM device can be replaced and the second powder can be added to the powder tank of another SLM device for processing.

[0023] Furthermore, the substrate includes a main plate and a sub-plate, the depth of the carbon sheet groove on the sub-plate is equal to the thickness of the commutator carbon sheet, the depth of the carbon sheet groove on the main plate is equal to the thickness of the commutator carbon sheet coated with the first powder, the uncoated commutator carbon sheet is placed in the sub-plate, and the commutator carbon sheet coated with the first powder is placed in the main plate, the sub-plate is used when coating with the first powder, and the main plate is used when coating with the second powder.

[0024] With this arrangement, since the depth of the carbon sheet groove on the sub-plate is equal to the thickness of the commutator carbon sheet, the top surface of the sub-plate can be aligned with the working surface of the SLM workbench, which is easier to operate. After setting the main board and sub-plate, the commutator carbon sheet to be plated can be placed in the sub-plate first, first plated with the first powder as a transition layer, and then the commutator carbon sheet can be taken out and placed in the main board. Since the depth of the carbon sheet groove on the main board is equal to the thickness of the commutator carbon sheet plated with the first powder, the alignment surface is also the top surface of the main board, which is convenient for alignment.

[0025] Furthermore, the material of the first powder is titanium powder, and the material of the second powder is copper powder.

[0026] In this way, titanium has both the properties of affinity with carbon and affinity with copper. In addition, titanium is a transition metal with high strength, low density, high hardness, high melting point and strong corrosion resistance. Carbon-titanium alloy has the high strength and toughness of titanium alloy, and also retains the lightweight characteristics of carbon fiber. At the same time, the copper powder used in additive manufacturing and the copper material of the shell are the same element. During the welding process, the mechanical properties are better. Titanium powder uses atomized spherical powder with a powder particle size of 10μm to 20μm. The powder performance requires high purity and good fluidity. During processing, the platform in the forming chamber needs to be preheated to 50℃ to 70℃. In order to avoid oxidation of the processed parts, inert gas (such as nitrogen or argon) needs to be introduced. The purity of the inert gas is 99.99%. The thickness of the scraper powder is 0.02mm-0.05mm each time, which can be flexibly selected according to the laser processing accuracy and the size of the processed metal powder particles. The processing laser power is 80-100W, and the laser scanning The scanning speed is 20mm / s-60mm / s, the scanning spacing is 0.08-0.12mm, and the scanning direction can be reasonably selected according to different equipment to achieve a higher surface finish. The copper powder uses atomized spherical powder with a powder particle size of 15μm-30μm. The powder performance requires high purity and good fluidity. During processing, the platform in the forming chamber needs to be preheated to 150℃ to 200℃. To avoid oxidation of the processed parts, argon protective gas with a purity of 99.99% needs to be introduced. The thickness of the scraper powder is 0.02mm-0.06mm each time, which can be flexibly selected according to the laser processing accuracy and the particle size of the processed metal powder. The scanning direction can be reasonably selected according to different equipment to prepare the copper film. The equipment processing uses a green laser with a laser power of 250-300W, a laser scanning speed of 900mm / s-1050mm / s, and a scanning spacing of 40μm-55μm, which can achieve a higher surface finish.

[0027] Furthermore, after step S5, the formed coating is surface treated by laser.

[0028] With such settings, there are uneven burrs and spheroidization around the titanium film after processing, so laser subtraction is required. The use of laser subtraction can reduce costs, increase efficiency and obtain better surface finish. The laser used for subtraction can be femtosecond laser or picosecond laser. After the titanium film is subtracted, the copper film is plated. After the copper film is plated, the copper film is subtracted by laser. After the subtraction, the laser can be used for polishing. When polishing the titanium film, a flat-top beam fiber infrared continuous laser is used. The laser power is 70W-200W, the energy density is 3J / cm2-3.82J / cm2, and the pulse width is 125ns-242ns; when polishing the copper film, a green laser is used. The laser wavelength is 515-535nm, the laser power is 2W-3W, and the pulse frequency is 800-1000KHZ. The polishing path can be reasonably selected according to different equipment, and the polishing process needs to be carried out in an argon atmosphere.

[0029] Furthermore, after step S5, the height of the substrate is lowered by using the auxiliary lifting platform, and then the scraper is returned to its original position.

[0030] In this way, lowering the basic height first and then returning the scraper can prevent the scraper from scraping the coated film surface when returning. The scraper can be used for the next scraping after returning. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of the structure of a substrate according to an embodiment of the present invention.

[0032] Figure 2 It is a schematic diagram of the commutator carbon segments in the carbon segment grooves on the sub-plate according to an embodiment of the present invention.

[0033] Figure 3 It is a schematic diagram of the commutator carbon segments in the carbon segment slots on the main board according to an embodiment of the present invention.

[0034] Figure 4 Schematic diagram of the film making process according to an embodiment of the present invention.

[0035] Meaning of the numbers in the figure: 1. SLM workbench, 101. Powder tank, 102. Processing tank, 2. Main lifting platform, 3. Auxiliary lifting platform, 4. Scraper, 5. Commutator carbon sheet, 6. High energy beam emitter, 7. Substrate, 701. Substrate body, 7011. Carbon sheet groove, 7012. Positioning column, 7013. Sealing groove, 702. Main board, 703. Auxiliary board. DETAILED DESCRIPTION

[0036] This specific embodiment is merely an explanation of this embodiment and is not a limitation of this embodiment. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed, but as long as they are within the scope of the claims of this embodiment, they are protected by patent law.

[0037] Referring to the accompanying drawings, the present invention provides the following technical solution: a substrate 7, comprising a substrate body 701, wherein one end surface of the substrate body 701 is provided with a carbon sheet groove 7011, and the diameter of the carbon sheet groove 7011 is not less than the outer diameter of the commutator carbon sheet 5.

[0038] With such arrangement, the commutator carbon segments 5 can be placed in the carbon segment grooves 7011 during processing, and then the substrate body 701 with the commutator carbon segments 5 can be placed in the SLM device for processing and coating. Several carbon segment grooves 7011 can be set as needed, so that multiple commutator carbon segments 5 can be coated at one time.

[0039] Preferably, in this embodiment, a positioning column 7012 is provided on the bottom surface of the carbon segment groove 7011 , and the diameter of the positioning column 7012 matches the inner diameter of the commutator carbon segment 5 , and the diameter of the carbon segment groove 7011 is larger than the outer diameter of the commutator carbon segment 5 .

[0040] With such arrangement, the diameter of the carbon segment groove 7011 is larger than the outer diameter of the commutator carbon segment 5. After the commutator carbon segment 5 is placed in, a gap will be formed between the inner wall of the carbon segment groove 7011 and the outer wall of the commutator carbon segment 5, which is convenient for taking out the carbon segment after film forming. The diameter difference between the two can be set to 3-4mm. After the positioning column 7012 is set, the commutator carbon segment 5 can be sleeved on the positioning column 7012 to fix its position, avoid sliding in the carbon segment groove 7011 and cause dislocation of the SLM equipment coating, and prevent the commutator carbon segment 5 from contacting the inner wall of the carbon segment groove 7011, avoid the commutator carbon segment 5 and the carbon segment groove 7011 from sticking together after the metal powder melts during the processing, and damage the substrate body 701.

[0041] Preferably, in this embodiment, the height of the positioning column 7012 is lower than the thickness of the commutator carbon segment 5 .

[0042] In this way, the top surface of the positioning column 7012 will be lower than the top surface of the commutator carbon segment 5 that needs to be plated, which can avoid the commutator carbon segment 5 and the positioning column 7012 sticking together after the metal powder melts during the processing and damaging the substrate body 701. The height difference between the two can be set to 0.5-1mm.

[0043] In this embodiment, preferably, the substrate 7 is provided with a sealing groove 7013 arranged around the side wall thereof.

[0044] With such arrangement, a sealing ring can be sleeved in the sealing groove 7013 on the side wall of the substrate body 701 to prevent powder from falling.

[0045] A film-making process for the working surface of a commutator carbon segment 5 comprises the following steps:

[0046] S1: Provide an SLM workbench 1, a main lifting platform 2, an auxiliary lifting platform 3, a scraper 4, a first powder, a high-energy beam emitter 6, and a substrate 7 as described in any one of claims 1 to 4, wherein the SLM workbench 1 is provided with a powder tank 101 and a processing tank 102, the main lifting platform 2 is adapted to the powder tank 101, the substrate 7 is adapted to the processing tank 102, the substrate 7 is located at the top of the auxiliary lifting platform 3, the carbon sheet tank 7011 is located at the top of the substrate 7, and add the first powder to the main lifting platform 2 in the powder tank 101;

[0047] S2: Place the commutator carbon segment 5 into the carbon segment slot 7011, and use the auxiliary lifting platform 3 to lift the substrate 7 to a position where the top surface of the commutator carbon segment 5 overlaps with the working surface of the SLM workbench 1;

[0048] S3: Use the auxiliary lifting platform 3 to lower the height of the substrate 7 to a required coating thickness, and use the main lifting platform 2 to lift the first powder in the powder tank 101 so that the first powder is pushed above the working surface of the SLM workbench 1;

[0049] S4: Use the scraper 4 to slide on the working surface of the SLM workbench 1 to push the first powder on the powder tank 101 onto the substrate 7 in the processing tank 102;

[0050] S5: the high energy beam emitter 6 irradiates the first powder located above the commutator carbon segment 5 .

[0051] With such an arrangement, the high-energy beam emitter 6 will scan the bed of the first powder layer by layer according to the path planned in the three-dimensional CAD slice model. The scanned first powder is melted and solidified to achieve a metallurgical bonding effect, and finally the metal parts designed by the model are obtained. The metal coating obtained in this way has stronger adhesion, the commutator is more durable, and the service life is longer.

[0052] Preferably, in this embodiment, a second powder is provided, and after step S5, the second powder is added to the powder tank 101, and the auxiliary lifting platform 3 is used to lift the substrate 7 to a position where the top surface of the commutator carbon segment 5 coated with the first powder coincides with the working surface of the SLM workbench 1, and then steps S3-S5 are performed again.

[0053] With such arrangement, the material of the first powder can be selected from materials that have affinity for carbon and also have affinity for the second powder. In this way, the first powder can be used as an intermediate transition layer to connect the coating of the second powder and the commutator carbon sheet 5. The metal coating obtained in this way has stronger adhesion, and the commutator is more durable and has a longer service life. The first powder in the powder tank 101 can be cleaned and replaced with the second powder, or an SLM device can be replaced and the second powder can be added to the powder tank 101 of another SLM device for processing.

[0054] In this embodiment, the substrate 7 preferably includes a main plate 702 and a sub-plate 703, the depth of the carbon plate groove 7011 on the sub-plate 703 is equal to the thickness of the commutator carbon plate 5, the depth of the carbon plate groove 7011 on the main plate 702 is equal to the thickness of the commutator carbon plate 5 coated with the first powder, the uncoated commutator carbon plate 5 is placed in the sub-plate 703, and the commutator carbon plate 5 coated with the first powder is placed in the main plate 702, the sub-plate 703 is used when coating the first powder, and the main plate 702 is used when coating the second powder.

[0055] With such arrangement, since the depth of the carbon sheet groove 7011 on the sub-plate 703 is equal to the thickness of the commutator carbon sheet 5, the top surface of the sub-plate 703 and the working surface of the SLM workbench 1 can be aligned, which is easier to operate. After setting the main board 702 and the sub-plate 703, the commutator carbon sheet 5 to be plated can be placed in the sub-plate 703 first, and first plated with the first powder as a transition layer, and then the commutator carbon sheet 5 can be taken out and placed in the main board 702. Since the depth of the carbon sheet groove 7011 on the main board 702 is equal to the thickness of the commutator carbon sheet 5 plated with the first powder, the alignment surface is also the top surface of the main board 702, which is convenient for alignment.

[0056] Preferably, in this embodiment, the material of the first powder is titanium powder, and the material of the second powder is copper powder.

[0057] In this way, titanium has both the properties of affinity with carbon and affinity with copper. In addition, titanium is a transition metal with high strength, low density, high hardness, high melting point and strong corrosion resistance. Carbon-titanium alloy has the high strength and toughness of titanium alloy, and also retains the lightweight characteristics of carbon fiber. At the same time, the copper powder used in additive manufacturing and the copper material of the shell are the same element. During the welding process, the mechanical properties are better. Titanium powder uses atomized spherical powder with a powder particle size of 10μm to 20μm. The powder performance requires high purity and good fluidity. During processing, the platform in the forming chamber needs to be preheated to 50℃ to 70℃. In order to avoid oxidation of the processed parts, inert gas (such as nitrogen or argon) needs to be introduced. The purity of the inert gas is 99.99%. The thickness of the scraper powder is 0.02mm-0.05mm each time, which can be flexibly selected according to the laser processing accuracy and the size of the processed metal powder particles. The processing laser power is 80-100W, and the laser scanning The scanning speed is 20mm / s-60mm / s, the scanning spacing is 0.08-0.12mm, and the scanning direction can be reasonably selected according to different equipment to achieve a higher surface finish. The copper powder uses atomized spherical powder with a powder particle size of 15μm-30μm. The powder performance requires high purity and good fluidity. During processing, the platform in the forming chamber needs to be preheated to 150℃ to 200℃. To avoid oxidation of the processed parts, argon protective gas with a purity of 99.99% needs to be introduced. The thickness of the scraper powder is 0.02mm-0.06mm each time, which can be flexibly selected according to the laser processing accuracy and the particle size of the processed metal powder. The scanning direction can be reasonably selected according to different equipment to prepare the copper film. The equipment processing uses a green laser with a laser power of 250-300W, a laser scanning speed of 900mm / s-1050mm / s, and a scanning spacing of 40μm-55μm, which can achieve a higher surface finish.

[0058] In this embodiment, preferably, after step S5, the formed coating is surface treated by laser.

[0059] With such settings, there are uneven burrs and spheroidization around the titanium film after processing, so laser subtraction is required. The use of laser subtraction can reduce costs, increase efficiency and obtain better surface finish. The laser used for subtraction can be femtosecond laser or picosecond laser. After the titanium film is subtracted, the copper film is plated. After the copper film is plated, the copper film is subtracted by laser. After the subtraction, the laser can be used for polishing. When polishing the titanium film, a flat-top beam fiber infrared continuous laser is used. The laser power is 70W-200W, the energy density is 3J / cm2-3.82J / cm2, and the pulse width is 125ns-242ns; when polishing the copper film, a green laser is used. The laser wavelength is 515-535nm, the laser power is 2W-3W, and the pulse frequency is 800-1000KHZ. The polishing path can be reasonably selected according to different equipment, and the polishing process needs to be carried out in an argon atmosphere.

[0060] In this embodiment, preferably, after step S5, the height of the substrate 7 is lowered by the auxiliary lifting platform 3, and then the scraper 4 is returned to its original position.

[0061] In this way, the basic height is lowered first and then the scraper 4 is returned to its original position, so that the scraper 4 can avoid scraping the coated film surface when returning to its original position, and the scraper 4 after returning to its original position can be used for the next scraping of powder.

[0062] Although the present invention has been described in detail with reference to the aforementioned embodiments, the protection scope of the present invention is not limited thereto, and any technician familiar with the technical field can make equivalent substitutions or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A commutator carbon sheet film making process, characterized in that: The steps include: S1: Provide an SLM workbench, a main lifting platform, a secondary lifting platform, a scraper, a first powder, a high-energy beam emitter and a substrate, wherein the substrate comprises a substrate body, a carbon sheet groove is provided on one side end face of the substrate body, the diameter of the carbon sheet groove is not less than the outer diameter of the commutator carbon sheet, the SLM workbench is provided with a powder groove and a processing groove, the main lifting platform is adapted to the powder groove, the substrate is adapted to the processing groove, the substrate is located on the top of the secondary lifting platform, the carbon sheet groove is located on the top of the substrate, and the first powder is added to the main lifting platform in the powder groove; S2: Place the commutator carbon segment into the carbon segment slot, and use the auxiliary lifting platform to lift the base plate to a position where the top surface of the commutator carbon segment overlaps with the working surface of the SLM workbench; S3: Use the auxiliary lifting platform to lower the height of the substrate to the required coating thickness, and use the main lifting platform to lift the first powder in the powder tank so that the first powder is pushed above the working surface of the SLM workbench; S4: Use a scraper to slide on the working surface of the SLM worktable to push the first powder on the powder tank to the top of the substrate in the processing tank; S5: The high energy beam emitter irradiates the first powder located above the commutator carbon segment; Provide the second powder, add the second powder into the powder tank after step S5, use the auxiliary lifting platform to lift the substrate to a position where the top surface of the commutator carbon segment coated with the first powder overlaps with the working surface of the SLM workbench, and then perform steps S3-S5 again; The substrate includes a main plate and a sub-plate, the depth of the carbon sheet groove on the sub-plate is equal to the thickness of the commutator carbon sheet, the depth of the carbon sheet groove on the main plate is equal to the thickness of the commutator carbon sheet coated with the first powder, the uncoated commutator carbon sheet is placed in the sub-plate, the commutator carbon sheet coated with the first powder is placed in the main plate, the sub-plate is used when the first powder is coated, and the main plate is used when the second powder is coated; The material of the first powder is titanium powder, and the material of the second powder is copper powder.

2. A commutator carbon sheet film making process according to claim 1, characterized in that: After step S5, the formed coating is surface treated by laser.

3. A commutator carbon sheet film making process according to claim 1, characterized in that: After step S5, the height of the substrate is lowered by the auxiliary lifting platform, and then the scraper is returned to its original position.

4. A commutator carbon sheet film making process according to claim 1, characterized in that: A positioning column is provided on the bottom surface of the carbon segment groove, the diameter of the positioning column is matched with the inner diameter of the commutator carbon segment, and the diameter of the carbon segment groove is larger than the outer diameter of the commutator carbon segment.

5. A commutator carbon sheet film making process according to claim 4, characterized in that: The height of the positioning column is lower than the thickness of the commutator carbon segment.

6. A commutator carbon sheet film making process according to claim 1, characterized in that: The substrate body is provided with a sealing groove arranged around the side wall thereof.

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