A method for machining a sector gear

Abstract

The present application belongs to the field of metal processing technology, and relates to a fan gear processing method. The method adopts a whole forging blank, removes the excess amount through rough machining, improves the mechanical properties through heat treatment, and then enters the fine machining stage, including fine machining, deburring and qualitative treatment, to ensure the machining precision and shape stability. Through accurate segmentation into two half circles and further vertical machining, and then using positioning pins and screw holes for accurate assembly, the matching precision is ensured. After hole machining, aging treatment is performed to remove stress, and the final machining stage ensures the finished product size, precision and tooth shape. In addition, surface oxidation treatment improves corrosion resistance and aesthetics. The method not only significantly improves the machining precision and overall quality of the fan gear, but also ensures the reinstallation precision after disassembly, and at the same time enhances the corrosion resistance of the gear, and is suitable for various precision transmission systems, and has wide application prospect and important practical value.

Description

Technical Field

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

[0002] In the field of mechanical transmission, sector gears, as a special type of gear, are widely used in various precision transmission systems. Especially for those sector gears designed to be detachable and composed of two half-circles (one toothed and the other toothless), their structural complexity and machining precision requirements are relatively high. However, in actual machining processes, these sector gears face numerous technical challenges.

[0003] First, because most of the wall thickness of a sector gear is very thin, while the tooth portion has a relatively thick wall, this uneven wall thickness distribution easily leads to deformation during processing and use. Deformation not only affects the meshing accuracy of the gear but may also cause the hole roundness to be substandard, thereby affecting the stability and reliability of the entire transmission system.

[0004] Secondly, since the sector gear is detachable, ensuring the fitting accuracy between the two half-turns during disassembly and reassembly, as well as the installation accuracy after reinstallation, is a problem that urgently needs to be solved. Traditional processing methods often fail to effectively control the amount of deformation after disassembly and reassembly, resulting in a high scrap rate.

[0005] Furthermore, as a critical component of sector gears, the machining and shape accuracy of the teeth directly affect the gear's transmission performance and service life. However, during the machining process, defects such as burrs and cracks are prone to occur on the teeth. These defects not only reduce the gear's transmission efficiency but may also cause malfunctions and increase maintenance costs during use.

[0006] To address the aforementioned issues, those skilled in the art have been exploring more effective processing methods and techniques. Research has revealed that adding qualitative and aging treatments between key processes can effectively remove processing stress, improve processing quality, and reduce deformation. Furthermore, adding locating pins between two gear components can significantly improve repeatability and prevent gear failures during use.

[0007] In summary, existing technologies suffer from problems such as easy deformation, non-compliance with hole roundness, and dimensional deviations during sector gear machining. Particularly during reassembly after disassembly, it is difficult to guarantee installation accuracy and gear machining precision. Therefore, developing a sector gear machining method that can effectively control deformation, improve machining accuracy and quality, and reduce scrap rate is of great significance for enhancing the stability and reliability of transmission systems. Summary of the Invention

[0008] In view of this, the purpose of this invention is to provide a method for processing sector gears, which reduces the scrap rate, controls the amount of deformation, and effectively solves the deformation problem after disassembly and assembly.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a method for machining sector gears, comprising the following steps:

[0010] S1, Material preparation stage: Select integral forging billets to ensure material consistency and stability, laying a solid foundation for subsequent processing;

[0011] S2, rough machining stage: the forging billet is initially turned to effectively remove most of the excess material, which facilitates subsequent machining.

[0012] S3, Heat treatment stage: Perform quenching and tempering heat treatment to achieve the required overall hardness and significantly improve the mechanical properties of the material;

[0013] S4, Finishing preparation stage: Further turning to remove the remaining material, so that the shape gradually approaches the finished size; flat grinding is performed on the surface to improve the surface finish and create good conditions for subsequent processing.

[0014] S5, Fine machining stage: Perform vertical machining to complete some fine machining processes and ensure machining accuracy; precisely cut the groove in the middle position, but do not cut it off completely, to make full preparation for subsequent division and strictly ensure cutting accuracy;

[0015] S6, Deburring and Conditioning Stage: Removes burrs generated during processing to ensure a smooth and flawless surface; performs conditioning treatment to stabilize the metal structure and effectively prevent deformation problems in subsequent processing.

[0016] S7, Segmentation and Semi-circle Machining Stage: The entire circle is precisely divided into two semi-circles along the original opening groove; the two semi-circles are further vertically machined to ensure the accuracy of their respective dimensions and shapes;

[0017] S7, Assembly and Grinding Stage: Use locating pins and screw holes to precisely assemble the two semicircles together to ensure fitting accuracy; perform fine grinding on the assembled surface to strictly guarantee flatness and parallelism;

[0018] S8, Hole Machining and Aging Treatment Stage: Preliminary machining of the holes is performed to prepare them for finishing; aging treatment is then carried out to effectively remove machining stress and stabilize dimensions and shape.

[0019] S9, Final Processing and Inspection Stage: The holes are finally processed to ensure that they meet the finished product size and accuracy requirements; fine cutting is performed to ensure the accuracy and shape of the teeth; burrs are removed from the teeth to ensure the smoothness of the teeth; surface oxidation treatment is performed to improve corrosion resistance and aesthetics; finally, the finished products are inspected and put into storage.

[0020] Optionally, in online cutting, a groove is cut but not completely severed, preparing for subsequent precise segmentation and ensuring cutting accuracy.

[0021] Optionally, aging treatment can be performed after semi-finishing to remove processing stress and stabilize dimensions and shape.

[0022] Optionally, locating pins can be used during machining and assembly to ensure repeatability of the two half-circles.

[0023] Optionally, the two half-turns can be tightened through the screw holes to ensure stability and accuracy after disassembly and assembly.

[0024] The beneficial effects of this invention are as follows:

[0025] 1) This invention cleverly integrates qualitative treatment and aging treatment between key processes. These two process steps work together to effectively remove the stress generated during processing, thereby significantly reducing the deformation of the sector gear. This improvement not only ensures the dimensional stability of the gear during processing, but also greatly enhances its reliability during use.

[0026] 2) Through a carefully designed processing flow and strict process control, this invention successfully improves the processing accuracy and overall quality of sector gears; both the shape accuracy of the teeth and the roundness of the holes have reached higher standards, thereby ensuring the precise meshing and efficient operation of the gears in the transmission system.

[0027] 3) Because this invention effectively solves the problems of deformation and dimensional deviation in the processing of sector gears, it significantly reduces the scrap rate; this achievement not only improves production efficiency, but also saves enterprises a lot of raw materials and processing costs;

[0028] 4) This invention, through the use of locating pins and screw holes, enables the sector gear to maintain extremely high fitting accuracy during disassembly and assembly. Even after multiple disassembly and assembly, the gear can still be easily restored to its original installation accuracy, thus meeting users' high requirements for the maintainability and reusability of the transmission system.

[0029] 5) Because the sector gears processed by this invention have higher machining accuracy and better dimensional stability, they can significantly improve the overall performance of the transmission system; both transmission efficiency and service life are significantly improved.

[0030] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0031] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0032] Figure 1 This is a schematic diagram of the sector gear structure of the present invention;

[0033] Figure 2 for Figure 1 The left view. Detailed Implementation

[0034] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0035] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0036] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0037] Please see Figures 1-2 This is a method for machining sector gears. It is designed for a sector gear assembled in upper and lower halves and fastened by screws and pins at both ends. Due to the uneven wall thickness, the part is very easy to deform. The inner hole size is large, Φ225H7. After machining and tightening the screws, the dimensional and positional tolerances are unstable, resulting in the gear accuracy failing to meet the requirements.

[0038] In this embodiment, the specific processing method is as follows:

[0039] I. Material Preparation Stage

[0040] High-quality integral forging blanks are selected as raw materials to ensure material consistency and stability. The material of the forging blank should meet design requirements and have good mechanical properties and machinability.

[0041] II. Rough Processing Stage

[0042] The forging billet undergoes preliminary turning (rough turning). Using a large lathe, the forging billet is rough turned according to the preset machining allowance to effectively remove most of the allowance, facilitating subsequent machining. During rough turning, the tool feed rate and depth of cut should be strictly controlled to avoid generating excessive cutting forces and heat, which could affect material properties and machining accuracy.

[0043] III. Heat Treatment Stage

[0044] The forged billet after rough turning undergoes quenching and tempering heat treatment. The billet is placed in a heat treatment furnace and heated and held at the preset temperature and time to achieve the required overall hardness, significantly improving the material's mechanical properties. During the heat treatment process, the furnace temperature and holding time must be strictly controlled to ensure the consistency and stability of the heat treatment effect.

[0045] IV. Preparatory Stage for Fine Processing

[0046] Further turning (finish turning). After heat treatment, the forging blank is finished turned to remove excess material, gradually bringing its shape closer to the finished dimensions. During finish turning, high-precision lathes and cutting tools should be used, and machining parameters should be strictly controlled to ensure machining accuracy and surface quality.

[0047] The surface is then subjected to surface grinding (surface grinding). Using a surface grinder, the finished surface is surface ground to improve its smoothness and create favorable conditions for subsequent processing. During the grinding process, appropriate grinding parameters and abrasives should be selected to ensure grinding effectiveness and surface quality.

[0048] V. Fine Processing Stage

[0049] Perform vertical machining (vertical machining center 1). Use a vertical machining center to perform some fine machining operations on the forging billet, such as milling and drilling, to ensure machining accuracy. During the machining process, high-precision tools and fixtures should be used, and machining parameters and paths should be strictly controlled to ensure machining accuracy and shape accuracy.

[0050] Precisely cut the groove in the middle (wire EDM 1). Using a wire EDM machine, precisely cut the groove in the middle of the forging billet, but do not cut it off completely, to prepare for subsequent segmentation. During the cutting process, the cutting speed and path should be strictly controlled to ensure cutting accuracy and the shape accuracy of the groove.

[0051] VI. Deburring and qualitative treatment stage

[0052] Remove burrs generated during processing (deburring with pliers). Use pliers to remove burrs from the surface and grooves of the forging blank, ensuring a smooth and flawless surface. During deburring, care should be taken to protect the surface and shape of the forging blank to avoid causing new damage or deformation.

[0053] Qualitative treatment is then performed. The forging billet is placed in a qualitative treatment furnace and heated and held at a preset temperature and time to stabilize the metal structure and effectively prevent deformation during subsequent processing. During the qualitative treatment process, the furnace temperature and holding time should be strictly controlled to ensure the consistency and stability of the qualitative treatment effect.

[0054] VII. Segmentation and Semi-circle Processing Stage

[0055] The entire circle is precisely divided into two semicircles along the existing opening groove (wire EDM 2). Using a wire EDM machine, the forging blank is precisely divided into two semicircles along the previously cut groove. During the cutting process, the cutting speed and path should be strictly controlled to ensure the segmentation accuracy and the shape accuracy of the semicircles.

[0056] Further vertical machining is performed on the two semicircles (each semicircle is vertically machined three times). Using a vertical machining center, further vertical machining, such as milling and drilling, is performed on the two semicircles to ensure the accuracy of their respective dimensions and shapes. During the machining process, high-precision tools and fixtures should be used, and machining parameters and paths should be strictly controlled to ensure machining accuracy and shape accuracy.

[0057] VIII. Assembly and Grinding Stage

[0058] The two semicircles are precisely assembled together using locating pins and screw holes (fitter assembly). According to the design drawings and process requirements, the two semicircles are precisely assembled together using locating pins and screw holes. During assembly, the assembly accuracy and fit tightness should be strictly controlled to ensure the accuracy and performance of the assembled sector gear.

[0059] The assembled surface is then subjected to fine grinding (surface grinding). Using a surface grinder, the surface of the assembled sector gear is finely ground to strictly ensure flatness and parallelism. During the grinding process, appropriate grinding parameters and abrasives should be selected to ensure grinding effect and surface quality.

[0060] IX. Hole Machining and Aging Treatment Stage

[0061] Preliminary machining (semi-finishing) of the holes. Using a drilling machine or boring machine, perform preliminary machining (semi-finishing) of the holes in the sector gear to prepare for finishing. During machining, the machining parameters and path should be strictly controlled to ensure the dimensional and shape accuracy of the holes.

[0062] Aging treatment is then performed. The sector gear is placed in an aging furnace and heated and held at the preset temperature and time to effectively remove processing stress and stabilize its dimensions and shape. During the aging process, the furnace temperature and holding time should be strictly controlled to ensure the consistency and stability of the aging treatment effect.

[0063] 10. Final Processing and Inspection Stage

[0064] Final machining (finishing) of the holes. Using a high-precision drilling machine or boring machine, perform final machining (finishing) of the holes in the sector gear to ensure that the finished dimensions and accuracy requirements are met. During the machining process, machining parameters and paths should be strictly controlled, and online inspection should be performed using high-precision measuring tools to ensure the dimensional and shape accuracy of the holes.

[0065] Perform precision cutting (wire EDM). Use a wire EDM machine to perform precision cutting on the teeth of the sector gear, ensuring the accuracy and shape of the teeth. During the cutting process, the cutting speed and path should be strictly controlled, and high-precision measuring tools should be used for online inspection to ensure the dimensional and shape accuracy of the teeth.

[0066] Remove burrs from the teeth (metallurgical deburring). Using metallurgical tools, deburr the teeth of the sector gear to ensure a smooth surface. During deburring, care should be taken to protect the shape and precision of the teeth to avoid causing new damage or deformation.

[0067] Surface oxidation treatment is performed. The sector gear is placed in an oxidation furnace and heated and held at the preset temperature and time to form a dense oxide film on the surface, improving corrosion resistance and aesthetics. During the oxidation process, the furnace temperature and holding time should be strictly controlled to ensure the consistency and stability of the oxidation treatment effect.

[0068] After inspection, the finished products are put into storage (components are put into the finished product warehouse). High-precision measuring tools are used to inspect the dimensions and performance of the sector gears to ensure that they meet the design requirements and quality standards. After passing the inspection, the sector gears are properly stored in the finished product warehouse for future use or sale.

[0069] The above description of specific embodiments provides a clear understanding of the entire process and key steps in sector gear machining. In actual production, adjustments and optimizations should be made according to specific design requirements and process conditions to ensure machining quality and production efficiency.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for machining sector gears, characterized in that, Includes the following steps: S1, Material preparation stage: Select integral forging billets to ensure material consistency and stability, laying a solid foundation for subsequent processing; S2, rough machining stage: the forging billet is initially turned to effectively remove most of the excess material, which facilitates subsequent machining. S3, Heat treatment stage: Perform quenching and tempering heat treatment to achieve the required overall hardness and significantly improve the mechanical properties of the material; S4, Finishing preparation stage: Further turning to remove the remaining material, so that the shape gradually approaches the finished size; flat grinding is performed on the surface to improve the surface finish and create good conditions for subsequent processing. S5, Fine machining stage: Perform vertical machining to complete the fine machining processes of milling and drilling to ensure machining accuracy; precisely cut the groove in the middle position, but do not cut it off completely, to make full preparation for subsequent division and strictly ensure cutting accuracy; S6, Deburring and qualitative treatment stage: Remove burrs generated during processing to ensure a smooth and flawless surface; place the forging billet in the treatment furnace and heat and hold it at the preset temperature and time to stabilize the metal structure and effectively prevent deformation problems in subsequent processing. S7, Segmentation and Semi-circle Machining Stage: The entire circle is precisely divided into two semi-circles along the original opening groove; the two semi-circles are further vertically machined to ensure the accuracy of their respective dimensions and shapes; S7, Assembly and Grinding Stage: Use locating pins and screw holes to precisely assemble the two semicircles together to ensure fitting accuracy; perform fine grinding on the assembled surface to strictly guarantee flatness and parallelism; S8, Hole Machining and Aging Treatment Stage: Preliminary machining of the holes is performed to prepare them for finishing; aging treatment is then carried out to effectively remove machining stress and stabilize dimensions and shape. S9, Final Processing and Inspection Stage: The holes are finally processed to ensure that they meet the finished product size and accuracy requirements; fine cutting is performed to ensure the accuracy and shape of the teeth; burrs are removed from the teeth to ensure the smoothness of the teeth; surface oxidation treatment is performed to improve corrosion resistance and aesthetics; finally, the finished products are inspected and put into storage.

2. The method for machining a sector gear according to claim 1, characterized in that: The groove is precisely cut in the middle position using wire cutting.

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