阅读说明：本技术 一种谐波柔轮的制造方法 (Manufacturing method of harmonic flexible gear ) 是由 石年平 邹安炳 于 2021-08-31 设计创作，主要内容包括：本发明公开一种谐波柔轮的制造方法,该方法中谐波柔轮的材料选用马氏体型沉淀硬化钢17-4PH,加工谐波柔轮的工艺为：齿坯粗加工→固溶处理→齿坯半精加工→深冷处理→齿坯精加工→调整处理→齿形加工→时效硬化处理。本发明将谐波柔轮的材料由30CrMnSiA或40CrNiMoA更换为马氏体型沉淀硬化钢17-4PH,齿坯粗加工后经固溶处理,基体硬度可达25～30HRC；齿坯半精加工后经深冷处理,可使材料组织均匀、细化和致密,降低薄壁齿坯精加工变形和应力,从而保证齿坯精加工尺寸稳定性；齿坯精加工后经调整处理,可进一步细化材料组织并使材料组织的均匀性再次得到提高,从而提高其冲击韧性。(The invention discloses a method for manufacturing a harmonic flexible gear, wherein the harmonic flexible gear is made of martensite precipitation hardening steel 17-4PH, and the process for processing the harmonic flexible gear comprises the following steps: rough machining of a gear blank → solution treatment → semi-finishing of the gear blank → cryogenic treatment → finishing of the gear blank → adjustment treatment → tooth profile machining → age hardening treatment. According to the invention, the material of the harmonic flexspline is changed from 30CrMnSiA or 40CrNiMoA to martensite precipitation hardening steel with 17-4PH, and the hardness of a matrix can reach 25-30 HRC after the rough machining of a gear blank and the solution treatment; the gear blank is subjected to cryogenic treatment after semi-finishing, so that the material structure is uniform, refined and compact, and the finish machining deformation and stress of the thin-wall gear blank are reduced, thereby ensuring the finish machining dimensional stability of the gear blank; after the gear blank is finely processed, the adjustment treatment can further refine the material structure and improve the uniformity of the material structure again, thereby improving the impact toughness.)

1. A manufacturing method of a harmonic flexible gear is characterized in that: the harmonic flexible gear is made of 17-4PH martensite precipitation hardening steel, and the process for machining the harmonic flexible gear comprises the following steps: rough machining of a gear blank → solution treatment → semi-finishing of the gear blank → cryogenic treatment → finishing of the gear blank → adjustment treatment → tooth profile machining → age hardening treatment.

2. The method of manufacturing a harmonic flexspline of claim 1, wherein: the solution treatment is completed according to the following steps: and (3) putting the rough machined harmonic flexible gear tooth blank into a vacuum furnace, heating the rough machined harmonic flexible gear tooth blank from room temperature to 1020-1060 ℃ at the heating rate of 8-10 ℃/minute, preserving the heat for 100-120 minutes, quickly transferring the rough machined harmonic flexible gear tooth blank into 30-50 ℃ bright quenching oil within 25 seconds, cooling to room temperature, and carrying out solution treatment to obtain the gear blank with the hardness of 25-30 HRC.

3. The method of manufacturing a harmonic flexspline of claim 1, wherein: the subzero treatment is completed according to the following steps: and (3) putting the semi-finished harmonic flexible gear tooth blank into a cryogenic treatment device, cooling the semi-finished harmonic flexible gear tooth blank from room temperature to-65 to-85 ℃ at a cooling rate of 2-4 ℃/min, preserving the temperature for 180-240 min, and taking out the semi-finished harmonic flexible gear tooth blank from the cryogenic treatment device to recover to the room temperature.

4. The method of manufacturing a harmonic flexspline of claim 1, wherein: the adjustment process is completed according to the following steps: and (3) putting the finished harmonic flexible gear tooth blank into a vacuum furnace, heating the finished harmonic flexible gear tooth blank from room temperature to 800-830 ℃ at a heating rate of 5-10 ℃/min, keeping the temperature for 300-360 min, discharging from the furnace, and air cooling to room temperature.

5. The method of manufacturing a harmonic flexspline of claim 1, wherein: the age hardening treatment is completed according to the following steps: putting the harmonic flexible gear into a vacuum furnace, heating the harmonic flexible gear from room temperature to 180-200 ℃ at a heating rate of 2-4 ℃/min, and preserving heat for 8-10 min; raising the temperature to 380-400 ℃ at the temperature rise rate of 2-4 ℃/min, and preserving the heat for 20-30 min; and finally, heating to 480-500 ℃ at the heating rate of 1-2 ℃/min, preserving the temperature for 120-180 min, discharging, and air cooling to room temperature.

Technical Field

The invention relates to a manufacturing method of a harmonic flexible gear, and belongs to the technical field of manufacturing of harmonic gears.

Background

The harmonic gear transmission is a gear transmission mode which utilizes controllable elastic deformation waves generated by a flexible gear to transmit motion or power, and mainly comprises three basic components, namely a flexible gear, a rigid gear and a wave generator. Among the three basic members, the harmonic flexspline is the least strong part because the harmonic flexspline is a thin-walled part that operates in a state of repeated elastic deformation in harmonic gear transmission, and is affected not only by bending stress due to deformation of the wave generator but also by bending moment of gear meshing force and torsional instability due to torque.

In the prior art, a harmonic flexible gear is generally manufactured by quenching and tempering 30CrMnSiA or 40CrNiMoA materials; the tensile strength and the yield strength of the 30CrMnSiA after thermal refining are 1080MPa and 835MPa respectively, and the tensile strength and the yield strength of the 40CrNiMoA after thermal refining are 980MPa and 835MPa respectively; the main disadvantages are: the material has low tensile strength and yield strength, and the manufactured harmonic flexible gear has low bearing capacity in use, is easy to generate fatigue fracture and has short service life.

Disclosure of Invention

In order to solve the technical problems, the invention provides a manufacturing method of a harmonic flexible gear, which greatly improves the tensile strength and the yield strength of a material by replacing a harmonic flexible gear material and improving a manufacturing process so as to overcome the defects of low bearing capacity, easy fatigue fracture and short service life of the harmonic flexible gear in the prior art.

The invention is formed as follows: a manufacturing method of a harmonic flexible gear is characterized in that the harmonic flexible gear is made of martensite precipitation hardening steel 17-4PH, and the process for machining the harmonic flexible gear comprises the following steps: rough machining of a gear blank → solution treatment → semi-finishing of the gear blank → cryogenic treatment → finishing of the gear blank → adjustment treatment → tooth profile machining → age hardening treatment.

In the method, the solution treatment is completed according to the following steps: and (3) putting the rough machined harmonic flexible gear tooth blank into a vacuum furnace, heating the rough machined harmonic flexible gear tooth blank from room temperature to 1020-1060 ℃ at the heating rate of 8-10 ℃/minute, preserving the heat for 100-120 minutes, quickly transferring the rough machined harmonic flexible gear tooth blank into 30-50 ℃ bright quenching oil within 25 seconds, cooling to room temperature, and carrying out solution treatment to obtain the gear blank with the hardness of 25-30 HRC.

In the above method, the adjustment process is completed according to the following steps: and (3) putting the finished harmonic flexible gear tooth blank into a vacuum furnace, heating the finished harmonic flexible gear tooth blank from room temperature to 800-830 ℃ at a heating rate of 5-10 ℃/min, keeping the temperature for 300-360 min, discharging from the furnace, and air cooling to room temperature.

In the method, the cryogenic treatment is completed according to the following steps: and (3) putting the semi-finished harmonic flexible gear tooth blank into a cryogenic treatment device, cooling the semi-finished harmonic flexible gear tooth blank from room temperature to-65 to-85 ℃ at a cooling rate of 2-4 ℃/min, preserving the temperature for 180-240 min, and taking out the semi-finished harmonic flexible gear tooth blank from the cryogenic treatment device to recover to the room temperature.

In the method, the age hardening treatment is completed according to the following steps: putting the harmonic flexible gear into a vacuum furnace, heating the harmonic flexible gear from room temperature to 180-200 ℃ at a heating rate of 2-4 ℃/min, and preserving heat for 8-10 min; raising the temperature to 380-400 ℃ at the temperature rise rate of 2-4 ℃/min, and preserving the heat for 20-30 min; and finally, heating to 480-500 ℃ at the heating rate of 1-2 ℃/min, preserving the temperature for 120-180 min, discharging, and air cooling to room temperature.

Due to the adoption of the technical scheme, the invention has the advantages that: according to the invention, the material of the harmonic flexspline is changed from 30CrMnSiA or 40CrNiMoA to martensite precipitation hardening steel with 17-4PH, and the hardness of a matrix can reach 25-30 HRC after the rough machining of a gear blank and the solution treatment; the gear blank is subjected to cryogenic treatment after semi-finishing, so that the material structure is uniform, refined and compact, and the finish machining deformation and stress of the thin-wall gear blank are reduced, thereby ensuring the finish machining dimensional stability of the gear blank; after the gear blank is finely processed, the material structure can be further refined and the uniformity of the material structure can be improved again through adjustment treatment, so that the impact toughness of the gear blank is improved; after the thin-wall harmonic flexible gear subjected to tooth profile machining is subjected to age hardening treatment, the hardness can reach 38-42 HRC, the tensile strength can reach 1600-1650 MPa, and the yield strength can reach 1420-1510 MPa.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following examples.

Example 1

The embodiment of the invention comprises the following steps: a manufacturing method of a harmonic flexible gear is characterized in that the harmonic flexible gear is made of martensite precipitation hardening steel 17-4PH, and the process for machining the harmonic flexible gear comprises the following steps: rough machining of a gear blank → solution treatment → semi-finishing of the gear blank → cryogenic treatment → finishing of the gear blank → adjustment treatment → tooth profile machining → age hardening treatment.

In this embodiment, the solution treatment is performed by the following steps: and (3) putting the rough machined harmonic flexible gear tooth blank into a vacuum furnace, heating the rough machined harmonic flexible gear tooth blank from room temperature to 1020 ℃ at the heating rate of 8 ℃/minute, preserving the heat for 100 minutes, rapidly transferring the rough machined harmonic flexible gear tooth blank into 30 ℃ bright quenching oil within 25 seconds, cooling to room temperature, and carrying out solution treatment to obtain the gear blank with the hardness of 25 HRC.

In this embodiment, the cryogenic treatment is completed according to the following steps: and (3) putting the semi-finished harmonic flexible gear tooth blank into a cryogenic treatment device, cooling the semi-finished harmonic flexible gear tooth blank from room temperature to-65 ℃ at a cooling rate of 2 ℃/minute, preserving the temperature for 180 minutes, and taking out the harmonic flexible gear tooth blank from the cryogenic treatment device to recover to the room temperature.

In this embodiment, the adjustment process is completed according to the following steps: and (3) putting the finished harmonic flexible gear tooth blank into a vacuum furnace, heating the finished harmonic flexible gear tooth blank from room temperature to 800 ℃ at the heating rate of 5 ℃/minute, keeping the temperature for 300 minutes, discharging from the furnace, and air cooling to room temperature.

In this embodiment, the age hardening treatment is completed by the following steps: putting the harmonic flexible gear into a vacuum furnace, heating the harmonic flexible gear from room temperature to 180 ℃ at the heating rate of 2 ℃/minute, and preserving the heat for 8 minutes; then heating to 380 ℃ at the heating rate of 2 ℃/min, and preserving the heat for 20 min; finally, the temperature is increased to 480 ℃ at the heating rate of 1 ℃/minute, and the temperature is preserved for 120 minutes, and then the product is taken out of the furnace and cooled to room temperature.

Example 2

The embodiment of the invention comprises the following steps: a manufacturing method of a harmonic flexible gear is characterized in that the harmonic flexible gear is made of martensite precipitation hardening steel 17-4PH, and the process for machining the harmonic flexible gear comprises the following steps: rough machining of a gear blank → solution treatment → semi-finishing of the gear blank → cryogenic treatment → finishing of the gear blank → adjustment treatment → tooth profile machining → age hardening treatment.

In this embodiment, the solution treatment is performed by the following steps: and (3) putting the rough machined harmonic flexible gear tooth blank into a vacuum furnace, heating the rough machined harmonic flexible gear tooth blank from room temperature to 1040 ℃ at the heating rate of 9 ℃/minute, preserving the heat for 110 minutes, rapidly transferring the rough machined harmonic flexible gear tooth blank into bright quenching oil at the temperature of 40 ℃ within 25 seconds, cooling to room temperature, and carrying out solid solution treatment to obtain the gear blank with the hardness of 28 HRC.

In this embodiment, the cryogenic treatment is completed according to the following steps: and (3) putting the semi-finished harmonic flexible gear tooth blank into a cryogenic treatment device, cooling the semi-finished harmonic flexible gear tooth blank from room temperature to-75 ℃ at a cooling rate of 3 ℃/minute, preserving the temperature for 200 minutes, and taking out the harmonic flexible gear tooth blank from the cryogenic treatment device to recover to the room temperature.

In this embodiment, the adjustment process is completed according to the following steps: and (3) putting the finished harmonic flexible gear tooth blank into a vacuum furnace, heating the finished harmonic flexible gear tooth blank from room temperature to 820 ℃ at the heating rate of 8 ℃/minute, keeping the temperature for 360 minutes, discharging from the furnace, and air cooling to room temperature.

In this embodiment, the age hardening treatment is completed by the following steps: putting the harmonic flexible gear into a vacuum furnace, heating the harmonic flexible gear from room temperature to 190 ℃ at the heating rate of 3 ℃/minute, and preserving the heat for 9 minutes; then heating to 390 ℃ at the heating rate of 3 ℃/min, and keeping the temperature for 25 min; finally, the temperature is raised to 490 ℃ at the heating rate of 1 ℃/minute, the temperature is kept for 160 minutes, and then the product is discharged from the furnace and cooled to the room temperature.

Example 3

The embodiment of the invention comprises the following steps: a manufacturing method of a harmonic flexible gear is characterized in that the harmonic flexible gear is made of martensite precipitation hardening steel 17-4PH, and the process for machining the harmonic flexible gear comprises the following steps: rough machining of a gear blank → solution treatment → semi-finishing of the gear blank → cryogenic treatment → finishing of the gear blank → adjustment treatment → tooth profile machining → age hardening treatment.

In this embodiment, the solution treatment is performed by the following steps: and (3) putting the rough machined harmonic flexible gear tooth blank into a vacuum furnace, heating the rough machined harmonic flexible gear tooth blank from room temperature to 1060 ℃ at the heating rate of 10 ℃/minute, preserving the temperature for 120 minutes, then quickly transferring into bright quenching oil at the temperature of 50 ℃ within 25 seconds to cool to the room temperature, and carrying out solid solution treatment to obtain the gear blank with the hardness of 30 HRC.

In this embodiment, the cryogenic treatment is completed according to the following steps: and (3) putting the semi-finished harmonic flexible gear tooth blank into a cryogenic treatment device, cooling the semi-finished harmonic flexible gear tooth blank from room temperature to-85 ℃ at a cooling rate of 4 ℃/min, preserving the temperature for 240 min, and taking out the harmonic flexible gear tooth blank from the cryogenic treatment device to recover to the room temperature.

In this embodiment, the adjustment process is completed according to the following steps: and (3) putting the finished harmonic flexible gear tooth blank into a vacuum furnace, heating the finished harmonic flexible gear tooth blank from room temperature to 830 ℃ at the heating rate of 10 ℃/minute, preserving the temperature for 360 minutes, discharging the harmonic flexible gear tooth blank out of the furnace, and air cooling the harmonic flexible gear tooth blank to the room temperature.

In this embodiment, the age hardening treatment is completed by the following steps: putting the harmonic flexible gear into a vacuum furnace, heating the harmonic flexible gear from room temperature to 200 ℃ at the heating rate of 4 ℃/minute, and preserving the heat for 10 minutes; then the temperature is raised to 400 ℃ at the heating rate of 4 ℃/min, and the temperature is kept for 30 min; finally, the temperature is raised to 500 ℃ at the heating rate of 2 ℃/min, and the temperature is preserved for 180 min, and then the product is discharged from the furnace and cooled to room temperature.