Grinding wheel structure for gear machining, gear grinding machine and gear polishing and grinding method

Abstract

The invention discloses a grinding wheel structure for gear machining, a gear grinding machine and a gear polishing and grinding method.The grinding wheel is divided into a grinding area and a polishing area in the axis direction, and the polishing area and the grinding area are coaxially arranged; a polishing molded line at an inlet of the polishing area is set according to elastic deformation generated by a polishing material due to engagement of a gear into the polishing area during polishing, and the elastic deformation generated by engagement of the gear into the material in the polishing area is compensated; after grinding machining of the gear is completed, the gear is directly polished through the polishing area; the finishing curve is determined according to the contact amount during gear grinding in the polishing stage, the molded line of the polishing area is corrected, the influence of elastic deformation of materials in the polishing area on the gear machining precision is eliminated, and meanwhile the surface roughness of the gear is improved.

Description

Technical Field

[0001] The invention relates to the technical field of gear processing, and in particular to a grinding wheel structure for gear processing, a gear grinding machine and a gear polishing and grinding method. Background Art

[0002] Worm wheel gear grinding machines have the characteristics of high precision, high efficiency and low cost in mass production. The roughness of the gear tooth surface is an important parameter that affects the efficiency of gear transmission. With the development of new energy vehicles, the speed of reducer gears has increased geometrically, which places higher and higher requirements on the roughness of gears. The existing ways to improve the roughness are: one is to hone the gears after grinding to improve the accuracy and roughness of the gears, but the roughness improvement of this solution is limited and requires a lot of additional costs; another way is to put the gears into a polishing machine for polishing. This method can obtain gears with higher roughness, but the uncertainty during polishing will reduce the accuracy of the gear tooth profile and tooth direction. The present invention greatly improves the roughness of the gear tooth surface while controlling the cost. Summary of the invention

[0003] Technical purpose: In view of the above-mentioned deficiencies in existing gear processing, the present invention discloses a grinding wheel structure for gear processing, a gear grinding machine and a gear polishing and grinding method.

[0004] Technical solution: To achieve the above technical objectives, the present invention adopts the following technical solution:

[0005] A grinding wheel structure for gear processing, the grinding wheel is divided into a grinding area and a polishing area along the axial direction, the polishing area and the grinding area are coaxially arranged, the polishing profile at the entrance of the polishing area is arranged according to the elastic deformation of the polishing material caused by the gear meshing into the polishing area during polishing, and the elastic deformation of the material in the polishing area caused by the gear meshing is compensated; after the gear grinding is completed, the gear is directly polished through the polishing area.

[0006] Preferably, the grinding area of ​​the present invention includes a grinding entrance area, a grinding use area and a grinding reserved area along the moving direction during gear processing. The grinding use area and the polishing area are separated by the grinding reserved area. The grinding use area is divided into a plurality of rough grinding sections and fine grinding sections. The rough grinding sections and the fine grinding sections are alternately arranged. A separation section is arranged between the rough grinding sections and the fine grinding sections. The fine grinding section is used as a rough grinding section for the next gear processing after a fine grinding.

[0007] Preferably, the length L of the grinding inlet zone of the present invention is A =L1+L2, where L1 is the grinding wheel helix angle interference converted into the grinding wheel axial length, and L2 is the gear meshing converted into the grinding wheel axial length.

[0008] Preferably, the length L of the rough grinding section of the present invention is B=(B+Z u +Z d )*Y f ; Length of fine grinding section L D =(B+Z u +Z d )*Y fd ; Among them, B represents the tooth width, Z u is the grinding upper entrance length, Z d Y is the length of the lower end outlet of the gear, f is the axial feed rate of the rough grinding wheel, Y fd is the axial feed rate of the fine grinding wheel.

[0009] Preferably, the length L of the partition section of the present invention is C =Z k *m, where Z k is the number of grinding wheel heads, and m is the grinding wheel module.

[0010] Preferably, the grinding reserved area L of the present invention E =L1+L3, where L1 is the helix angle interference of the grinding wheel converted into the axial length of the grinding wheel, and L3 is the meshing length between the grinding wheel and the gear.

[0011] Preferably, the polishing area of ​​the present invention is divided into a polishing entrance area, a polishing use area and a polishing meshing area in sequence along the moving direction during gear processing, the length of the polishing entrance area is consistent with the length of the grinding entrance area, and the length of the polishing meshing area is consistent with the length of the grinding reserved area; the polishing profile at the entrance of the polishing use area is ΔX=σ i *ΔY / ΔB, where ΔX is the modification change in the X-axis direction, ΔY is the modification change in the Y-axis direction, and ΔB is the gear width feed amount; σ0 is the outward elastic deformation of the polishing area at the polishing speed; σ1 is the elastic deformation after the gear is fully engaged with the polishing entrance. is the percentage of gear engagement.

[0012] The invention discloses a gear grinding machine having the above-mentioned grinding wheel structure. The grinding wheel is installed on a processing spindle of the gear grinding machine, and the grinding wheel is driven to rotate by the processing spindle.

[0013] The present invention discloses a gear polishing and grinding method, which uses the grinding wheel structure, determines the profile of the grinding wheel polishing area for compensating for the elastic deformation generated by meshing with the gear according to the specifications of the gear to be processed, installs the grinding wheel after the profile is confirmed on a gear grinding machine, and then meshes the gear workpiece to be processed from the entrance of the grinding wheel grinding area and feeds along the axial direction of the grinding wheel, passes through the grinding area and the polishing area in turn, and the grinding wheel rotates under the drive of the processing spindle of the gear grinding machine to perform gear processing, thereby completing the rough grinding, fine grinding and polishing operations on the gear.

[0014] Preferably, the process of determining the profile of the grinding wheel polishing area for compensating for the elastic deformation caused by meshing with the gear according to the specifications of the gear to be processed in the present invention comprises:

[0015] Determine the rotation speed of the grinding wheel during polishing, and determine the elastic deformation σ0 of the polishing area when it is not in contact with the gear and the elastic deformation σ1 of the polishing area caused by the meshing of the gear and the polishing area at the corresponding rotation speed based on the material of the polishing area of ​​the grinding wheel. When the gear meshes with the polishing area of ​​the grinding wheel, the polishing area changes between σ0 and σ1. Determine the meshing change corresponding to each position of the polishing area according to the progress of the gear meshing is the percentage of contact with the polished area during gear meshing, Where Δz i is the axial feed of the workpiece during gear machining, β i is the helix angle under the current gear meshing diameter, It is the maximum contact amount between the gear and the polished area when the gear is meshing.

[0016] Beneficial effects: The present invention discloses a grinding wheel structure, a gear grinding machine and a gear polishing and grinding method for gear processing. In the polishing stage, a dressing curve is determined according to the contact amount during gear grinding, and the profile of the polishing area is corrected to eliminate the influence of the elastic deformation of the material in the polishing area on the gear processing accuracy, while improving the surface roughness of the gear. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0018] Figure 1 It is a schematic diagram of the structure of the gear grinding machine of the present invention;

[0019] Figure 2 This is a schematic diagram of the gear grinding machine of the present invention performing gear processing;

[0020] Figure 3 It is a schematic diagram of the division of the grinding wheel processing area of ​​the present invention;

[0021] Figure 4 It is a schematic diagram of the grinding area division of the present invention;

[0022] Figure 5 It is a schematic diagram of the polishing area division of the present invention;

[0023] Figure 6 This is a schematic diagram of the polishing area after correction of the present invention;

[0024] Figure 7 This is a process flow chart of gear grinding and polishing using a grinding wheel in the present invention;

[0025] Among them, 1 is a grinding wheel, 2 is a gear grinder, and 3 is a processing spindle. DETAILED DESCRIPTION

[0026] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are set forth herein below. Each embodiment and example is provided by way of explanation of the apparatus, composition and materials of the present disclosure, rather than limitation. On the contrary, the following description provides a convenient illustration of an exemplary embodiment for implementing the present disclosure. In fact, it will be clear to those skilled in the art that various modifications and variations may be made in the teachings of the present disclosure without departing from the scope or spirit of the present disclosure.

[0027] like Figure 1-Figure 7 As shown, the present invention discloses a grinding wheel structure for gear processing, wherein the grinding wheel is divided into a grinding area and a polishing area along the axial direction, the polishing area and the grinding area are coaxially arranged, and the polishing profile at the entrance of the polishing area is arranged according to the elastic deformation of the polishing material caused by the gear meshing into the polishing area during polishing, so as to compensate for the elastic deformation of the material in the polishing area caused by the gear meshing; after completing the grinding process of the gear, the gear is directly polished through the polishing area.

[0028] The material of the polishing area is generally resin material, which has large elastic deformation. When performing gear polishing, there will be different deformations in the three intervals: no workpiece and no contact with the grinding wheel, half of the workpiece is in contact with the grinding wheel, and the workpiece is in full contact with the grinding wheel. This deformation affects the tooth shape and tooth direction accuracy of the gear, making it impossible to guarantee the processing quality of the gear. Therefore, it is necessary to design the profile of the polishing area according to the deformation to eliminate the influence of deformation on gear processing.

[0029] The grinding area of ​​the present invention includes a grinding entrance area, a grinding use area and a grinding reserved area along the moving direction during gear processing. The grinding use area and the polishing area are separated by the grinding reserved area. The grinding use area is divided into a plurality of rough grinding sections and fine grinding sections. The rough grinding sections and the fine grinding sections are alternately arranged. A separation section is arranged between the rough grinding sections and the fine grinding sections. The fine grinding section is used as a rough grinding section for the next gear processing after one fine grinding. The grinding area of ​​each grinding wheel can be provided with multiple groups of rough grinding sections and fine grinding sections according to demand, so as to realize the processing of multiple gears using the same grinding wheel. In addition, the fine grinding section of the previous gear is used as the rough grinding section for the next gear processing. The wear of the grinding wheel can be reduced without affecting the gear processing quality, thereby achieving the purpose of reducing the gear processing cost.

[0030] In an embodiment of the present invention, Figure 4 As shown, the length L of the grinding entrance zone of the present invention is A=L1+L2, by controlling the length of the grinding entrance area to ensure the gear grinding, and thus ensure the processing accuracy, where L1 is the grinding wheel helix angle interference converted into the grinding wheel axial length, Where m is the grinding wheel modulus, α is the grinding wheel pressure angle, λ is the grinding wheel helix angle, and L2 is the axial length of the grinding wheel converted from gear meshing. Where d a is the tooth tip circle of the gear workpiece, d b The base circle of the gear workpiece, d is the pitch circle of the gear workpiece, α t is the gear end face pressure angle.

[0031] The length L of the rough grinding section of the present invention B =(B+Z u +Z d )*Y f ; Length of fine grinding section L D =(B+Z u +Z d )*Y fd ; Among them, B represents the tooth width, Z u is the grinding upper entrance length, Z d Y is the length of the lower end outlet of the gear, f is the axial feed rate of the rough grinding wheel, Y fd is the axial feed rate of the fine grinding wheel. According to the processing requirements of the gear workpiece, the length of the corresponding rough grinding section and fine grinding section is selected to ensure the complete processing of the gear. At the same time, the setting of the separation section can avoid the influence of the rough grinding section grinding wheel on the fine grinding of the gear. The length of the separation section L C =Z k *m, where Z k is the number of grinding wheel heads, and m is the grinding wheel module.

[0032] The grinding reserved area L of the present invention E =L1+L3, through the grinding reserved area to avoid the gear moving into the polishing area during grinding, where L1 is the grinding wheel helix angle interference converted into the grinding wheel axial length, L3 is the meshing length between the grinding wheel and the gear, Where, H1 grinding wheel tooth height, α t is the gear end face pressure angle.

[0033] The division of the corresponding polishing area also refers to the division of the grinding area of ​​the gear, such as Figure 5 and Figure 6As shown, the polishing area of ​​the present invention is divided into a polishing entry area, a polishing use area and a polishing meshing-out area in sequence along the moving direction of the gear during machining. The length of the polishing entry area is consistent with the length of the grinding entry area, and the length of the polishing meshing-out area is consistent with the length of the grinding reserved area. The length of the polishing use area needs to be greater than the sum of the gear meshing-in and meshing-out lengths. Since the polishing area is less worn, it is not necessary to set up multiple polishing use areas. The polishing profile at the entrance of the polishing use area is ΔX=σ i *ΔY / ΔB, where ΔX is the modification change in the X-axis direction, ΔY is the modification change in the Y-axis direction, and ΔB is the gear width feed amount; σ0 is the outward elastic deformation of the polishing area at the polishing speed; σ1 is the elastic deformation after the gear is fully engaged with the polishing entrance. is the percentage of gear engagement, It is the contact amount between the gear and the polishing area when the gear is meshing; the profile at the exit of the polishing area is symmetrical with the entrance, and there is a straight line transition between the two. By setting the profile design at the entrance and exit of the polishing area, it can be ensured that the elastic deformation that may be produced by the polishing material during the meshing and meshing process of the gear can be corrected to ensure the gear tooth accuracy after polishing; the profile trimming of the polishing area on the grinding wheel can be done by Figure 1 In the method shown, after the grinding wheel is installed on the gear grinding machine, the corresponding profile is processed on the grinding wheel using a dressing wheel, and then the dressed grinding wheel is used for gear grinding and polishing.

[0034] like Figure 1 and Figure 2 As shown, the present invention also discloses a gear grinding machine having the above-mentioned grinding wheel structure, wherein the grinding wheel 1 is mounted on a processing spindle 3 of the gear grinding machine 2, and the processing spindle 3 drives the grinding wheel 1 to rotate. According to the length of the grinding area of ​​the grinding wheel and the specifications of the gear workpiece to be processed, the same grinding wheel structure is used to grind and polish multiple groups of gears. In the process from grinding to polishing, there is no need to reposition the gears like a polishing machine, thereby ensuring the processing quality.

[0035] like Figure 7As shown, the present invention discloses a gear polishing and grinding method, using the above-mentioned grinding wheel structure, according to the specifications of the gear to be processed, the profile of the grinding wheel polishing area for compensating for the elastic deformation caused by meshing with the gear is determined, the grinding wheel after the profile is confirmed is installed on a gear grinding machine, and then the gear workpiece to be processed is meshed from the entrance of the grinding wheel grinding area and fed along the axial direction of the grinding wheel, passing through the grinding area and the polishing area in turn, the grinding wheel is driven by the processing spindle of the gear grinding machine to rotate to perform gear processing, complete the rough grinding, fine grinding and polishing operations on the gear, and the rough grinding processing end point of each gear is used as the grinding starting point of the rough grinding of the next gear, and the fine grinding area is reused, so as to reduce the consumables cost of the processing equipment without affecting the gear processing quality. Figure 7 An example of performing gear machining twice is given. For subsequent gear machining, the method of determining the grinding starting point during the first and second machining can be referred to until the upper limit of the number of gears that the grinding wheel can machine is reached. After replacing a new grinding wheel, the machining process is repeated.

[0036] The process of determining the profile of the grinding wheel polishing area for compensating for the elastic deformation caused by meshing with the gear according to the specifications of the gear to be processed in the present invention comprises:

[0037] Determine the rotation speed of the grinding wheel during polishing, and determine the elastic deformation σ0 of the polishing area when it is not in contact with the gear and the elastic deformation σ1 of the polishing area caused by the meshing of the gear and the polishing area at the corresponding rotation speed based on the material of the polishing area of ​​the grinding wheel. When the gear meshes with the polishing area of ​​the grinding wheel, the polishing area changes between σ0 and σ1. Determine the meshing change corresponding to each position of the polishing area according to the progress of the gear meshing is the percentage of contact with the polished area during gear meshing, Where Δz i is the axial feed of the workpiece during gear machining, β i is the helix angle under the current gear meshing diameter, It is the maximum contact amount between the gear and the polished area when the gear is meshing.

[0038] Through the processing method of the present invention, the polishing area correction line can be designed according to the characteristics of the polishing material, the influence of material elastic deformation on the gear polishing process can be eliminated, the polishing accuracy can be improved and the equipment cost of gear processing can be reduced.

Claims

1. A grinding wheel structure for gear processing, characterized in that: The grinding wheel is divided into a grinding area and a polishing area along the axial direction. The polishing area and the grinding area are coaxially arranged. The polishing profile at the entrance of the polishing area is arranged according to the elastic deformation of the polishing material caused by the gear meshing into the polishing area during polishing, so as to compensate for the elastic deformation of the material in the polishing area caused by the gear meshing. After the grinding process of the gear is completed, the gear is directly polished through the polishing area.

2. A grinding wheel structure for gear processing according to claim 1, characterized in that: The grinding area includes a grinding entrance area, a grinding use area and a grinding reserved area along the moving direction during gear processing. The grinding use area and the polishing area are separated by the grinding reserved area. The grinding use area is divided into a plurality of rough grinding sections and fine grinding sections. The rough grinding sections and the fine grinding sections are alternately arranged. A separation section is arranged between the rough grinding sections and the fine grinding sections. The fine grinding section is used as a rough grinding section for the next gear processing after one fine grinding.

3. A grinding wheel structure for gear processing according to claim 2, characterized in that: The length L of the grinding entry zone A =L1+L2, where L1 is the grinding wheel helix angle interference converted into the grinding wheel axial length, and L2 is the gear meshing converted into the grinding wheel axial length.

4. A grinding wheel structure for gear machining according to claim 2 or 3, characterized in that: The length of the rough grinding section L B =(B+Z u +Z d )*Y f ; Length of fine grinding section L D =(B+Z u +Z d )*Y fd ; Among them, B represents the tooth width, Z u is the grinding upper entrance length, Z d Y is the length of the lower end outlet of the gear, f is the axial feed rate of the rough grinding wheel, Y fd is the axial feed rate of the fine grinding wheel.

5. A grinding wheel structure for gear processing according to claim 2, characterized in that: The length L of the partition C =Z k *m, where Z k is the number of grinding wheel heads, and m is the grinding wheel module.

6. A grinding wheel structure for gear machining according to claim 3, characterized in that: The grinding reserved area L E =L1+L3, where L1 is the helix angle interference of the grinding wheel converted into the axial length of the grinding wheel, and L3 is the meshing length between the grinding wheel and the gear.

7. A grinding wheel structure for gear machining according to claim 3, characterized in that: The polishing area is divided into a polishing entrance area, a polishing use area and a polishing meshing area in sequence along the moving direction during gear processing. The length of the polishing entrance area is consistent with the length of the grinding entrance area, and the length of the polishing meshing area is consistent with the length of the grinding reserved area. The polishing profile at the entrance of the polishing use area is ΔX=σ i *ΔY / ΔB, where ΔX is the modification change in the X-axis direction, ΔY is the modification change in the Y-axis direction, and ΔB is the gear width feed amount; σ0 is the outward elastic deformation of the polishing area at the polishing speed; σ1 is the elastic deformation after the gear is fully engaged with the polishing entrance. is the percentage of gear engagement.

8. A gear grinding machine, characterized in that: The grinding wheel structure has the grinding wheel structure as claimed in any one of claims 1 to 7, wherein the grinding wheel (1) is mounted on a machining spindle (3) of a gear grinding machine (2), and the grinding wheel (1) is driven to rotate by the machining spindle (3).

9. A gear polishing and grinding method, using the grinding wheel structure according to any one of claims 1 to 7, characterized in that: According to the specifications of the gear to be processed, the profile of the grinding wheel polishing area is determined to compensate for the elastic deformation caused by the meshing with the gear. The grinding wheel with the confirmed profile is installed on the gear grinding machine. Then the gear workpiece to be processed is meshed from the entrance of the grinding area of ​​the grinding wheel and fed along the axial direction of the grinding wheel, passing through the grinding area and polishing area in turn. The grinding wheel rotates driven by the machining spindle of the gear grinding machine to perform gear processing and complete the rough grinding, fine grinding and polishing operations of the gear.

10. A gear polishing and grinding method according to claim 9, characterized in that: The process of determining the profile of the grinding wheel polishing area to compensate for the elastic deformation caused by meshing with the gear according to the specifications of the gear to be processed includes: Determine the rotation speed of the grinding wheel during polishing, and determine the elastic deformation σ0 of the polishing area when it is not in contact with the gear and the elastic deformation σ1 of the polishing area caused by the meshing of the gear and the polishing area at the corresponding rotation speed based on the material of the polishing area of ​​the grinding wheel. When the gear meshes with the polishing area of ​​the grinding wheel, the polishing area changes between σ0 and σ1. Determine the meshing change corresponding to each position of the polishing area according to the progress of the gear meshing is the percentage of contact with the polished area during gear meshing, Where Δz i is the axial feed of the workpiece during gear machining, β i is the helix angle under the current gear meshing diameter, It is the maximum contact between the gear and the polished area when the gear is meshing.

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