Gear Processing Technology: Selection of Gear Processing Reference

2022-09-08

The gear processing technology often varies in the selection of processing references due to the different structural shapes of gears. For shaft gears, positioning is mainly done using the vertex hole; for hollow shafts, after drilling the central inner hole, positioning is done using the inclined surfaces of the holes at both ends; when the hole diameter is large, a cone plug is used. Vertex positioning has high precision and can achieve reference coincidence and unification. For hole gears, the following two positioning and clamping methods are commonly used during tooth surface processing. 1. Positioning by inner hole and end face This positioning method uses the inner hole of the workpiece to determine the positioning location, and the end face serves as the axial positioning reference, with clamping against the end face. This allows the positioning reference, design reference, assembly reference, and measurement reference to coincide, resulting in high positioning accuracy, making it suitable for mass production. However, it requires high manufacturing precision for the fixture. 2. Positioning by outer circle and end face When the fit clearance between the workpiece and the machining center shaft is relatively large, a dial gauge is used to correct the outer circle to determine the center position, and the end face is used for axial positioning, with clamping from the other end face. This positioning method requires calibration for each workpiece, resulting in lower productivity; at the same time, it has high requirements for the coaxiality of the inner and outer circles of the gear blank, while the precision requirements for the fixture are not high, making it suitable for single-piece and small batch production.

The gear module is calculated using the formula: \[ m = \frac{d}{N} \] Where: - \( m \) is the module, - \( d \) is the pitch diameter of the gear, - \( N \) is the number of teeth on the gear.

2022-08-10

What is the gear module? How is it calculated? What is the calculation formula? For friends who are new to gear processing, it may not be very clear. Next, the gear processing manufacturer Shouyue Electromechanical will share the calculation formula for gear modules for reference and understanding. 1. What is the gear module? The gear module is an abstract measure used to quantify the size of gear teeth. It is a factor that determines the size of the teeth and is one of the most basic parameters for gear teeth manufacturing. The gear module is related to several important parameters that make up gear products, such as the pitch circle, pressure angle, number of teeth, and tooth pitch. 1. The standard module series is formulated based on requirements for design, manufacturing, and inspection. The modules for spur gears, helical gears, and bevel gears can all refer to the standard module series table. 2. Many custom mass-produced gears use non-standard modules. 3. For gears with non-spur teeth, there are differences in normal module mn, face module ms, and axial module mx, all of which are based on their respective tooth pitches (normal tooth pitch, face tooth pitch, and axial tooth pitch) and the ratio to pi, measured in millimeters. 4. For bevel gears, there are distinctions between large end module me, average module mm, and small end module m1. 2. How to calculate the gear module? What is the calculation formula for the gear module? 1. Calculation formula for helical gear module: a. Pitch circle diameter calculation Do = (number of teeth Z * module m) / cosB b. Diameter calculation Dk = ((number of teeth Z * module m) / cosB) + (module m * 2) c. Circumference of the gear when it rotates one circle Z = pitch circle diameter Do * π Note: The calculation for the installation center distance from the gear center point to the bottom surface of the rack is: installation center distance Hb = (pitch circle diameter Do / 2) + meshing center line Ho. 2. Calculation formula for spur gear module: a. Pitch circle diameter calculation Do = number of teeth Z * module m b. Diameter calculation Dk = (number of teeth Z * module m) + (module m * 2) c. Circumference of the gear when it rotates one circle Z = pitch circle diameter Do * π Note: The calculation for the installation center distance from the gear center point to the bottom surface of the rack is: installation center distance Hb = (pitch circle diameter Do / 2) + meshing center line Ho. If the number of teeth of the gear is fixed, the larger the module, the larger the radial size of the wheel; the larger the module, the higher and thicker the gear teeth; with a constant module, the larger the number of teeth, the more gradual the involute, and the thickness of the tooth tip circle and tooth root circle will correspondingly increase; with a fixed number of teeth, the larger the module, the larger the gear teeth, the stronger the resistance to breakage, and of course, the gear blank will also be larger, resulting in larger spatial dimensions. Therefore, when selecting gear processing products, it is necessary to consider various parameters comprehensively and choose the appropriate model specifications based on the actual application requirements.

Introduction to the Types and Characteristics of Precision Gears

2022-07-29

1. Helical Gears: Helical gears are widely used in various applications. Although they may appear more complex than other types of gears, they are very convenient to use. Helical gears can intermesh on two axes in space, whether they are perpendicular or parallel. Additionally, the direction of the small gears can be the same or opposite. Therefore, the impact of these gears is quite significant. 2. Spur Gears and Bevel Gears: Compared to the helical gears mentioned above, spur gears and bevel gears seem to have a more monotonous function. This is because spur gears were invented first. The two large and two small gears of this type can only be used on parallel axes, with both gears rotating in the same direction. Although they have been in production for a long time, they are still used, albeit in smaller quantities. 3. Characteristics of Bevel Gears: In fact, bevel gears and spur gears are similar in function, with one being straight and the other being angled. In some cases, you may need a bevel gear, while in others, a spur gear is required. Besides these two types, there are also bevel gears, which have a unique hammer-like shape. There are many types of precision gears, but the three mentioned above are common and play an important role. Therefore, these three types are familiar and widely used. If you want to purchase precision gears, you can choose based on actual needs, as long as you find the right size and model, it will bring convenience to people.

The Great Wall Gear Factory wishes all candidates success in their exams and a victorious start.

2022-06-07

Years of hard study in the cold window, for a moment of success; A thousand days sharpening a sword, for a day of inspection! To the children taking the college entrance examination, I wish you all success in the exam! At this point in the exam, it's all about patience, it's all about mindset. Don't be nervous, don't be anxious, don't rush, Actually, everyone is the same, If it's hard for me, it's hard for you, don't be afraid of difficulty, we face it fearlessly; If it's easy for me, it's easy for you, don't be careless, we proceed steadily! Come on, kids! We must ensure that our results match the effort we have put in!

What are the main advantages of the widespread application of precision gears?

2022-05-12

Precision gears are one of the widely used transmission mechanisms, present in all types of machinery. They can flexibly adapt to machines, allowing mechanical equipment to operate more safely and efficiently. They have made outstanding contributions across various industries, and the cleverly designed gears that adapt to working machinery are the soul of production work. Why are precision gears so remarkable? Why are they widely used in various fields? The main reasons are the advantages of precision gears: 1. Precision gears, through passive relationships, allow for a wider range of circumferential speeds and power, resulting in higher mechanical production efficiency and more stable transmission ratios. Precision gears are variable; the driving wheel drives the driven wheel, controlling precisely and effectively increasing the circumferential speed and power range of the gears, making them more time-saving and labor-saving compared to a single gear, thus improving efficiency. 2. Longer lifespan of gears: Due to their excellent performance, they can achieve transmission between parallel axes, crossed axes at any angle, and crossed axes at any angle. More possibilities lead to more working possibilities. Precision gears require higher manufacturing and installation accuracy, which extends the lifespan of the gears to some extent and reduces the costs of mechanical maintenance and replacement. 3. Main disadvantages of gear mechanisms: They require higher manufacturing and installation precision, leading to higher costs, and are not suitable for achieving transmission between two shafts over long distances. Higher requirements inevitably demand more investment in energy and funds. For long-distance transmission between two shafts, belt drives provide a safer and more labor-saving alternative compared to gears.

The manufacturing precision requirements for gears are quite high.

2022-04-07

The selection of processing benchmarks for gears often varies due to differences in the structural shapes of the gears. For shaft gears, positioning is mainly done using vertex holes; for hollow shafts, after drilling the central hole, positioning is done using the inclined surfaces of the holes at both ends; when the hole diameter is large, a cone plug is used. Vertex positioning has high precision and can achieve benchmark coincidence and unification. For hole gears, two common positioning and clamping methods are often used during tooth surface processing. 1. Inner hole and end face positioning: This positioning method uses the inner hole of the workpiece to determine the positioning location, and the end face serves as the axial positioning benchmark, with clamping done against the end face. This allows the positioning benchmark, design benchmark, assembly benchmark, and measurement benchmark to coincide, resulting in high positioning accuracy, making it suitable for mass production. However, this method requires high precision in the manufacturing of the fixture. To improve gear precision and reduce tooth surface roughness, methods such as grinding or polishing can be employed. However, for gears that have already been processed and lack grinding allowance, using conventional grinding agents can be time-consuming and labor-intensive with not very obvious results. Therefore, a new process using CRONEX special grinding materials is adopted. For reducer gears, EP6 CRONEX abrasives are used for grinding. During grinding, the process starts with low-speed no-load grinding, followed by accelerated pressure grinding (controlling pressure through load control). After grinding, the tooth surface roughness is reduced from the original 2.25μm to 0.25μm. The Chinese gear industry is mainly composed of three parts: industrial gears, vehicle gears, and gear equipment. Among them, vehicle gears account for 60% of the market share; industrial gears consist of general industrial, specialized, and special gears, with market shares of 18%, 12%, and 8%, respectively; gear equipment accounts for 2% of the market share. The gear industry should improve industry concentration through market competition and integration, forming a number of large, medium, and small enterprises with assets of several billion, 500 million, and 100 million yuan; through the design and development of products with independent intellectual property rights, a group of leading enterprises in vehicle transmission systems (gearboxes, drive axle assemblies) should be formed, integrating the capabilities and resources of the gear industry through the supporting capabilities of leading enterprises; achieving specialized and networked support, forming a large number of distinctive processes, distinctive products, and well-known enterprises with rapid response capabilities; and through technological transformation, realizing the transformation of modern gear manufacturing enterprises.

Four Key Points to Note in CNC Lathe Machining

2022-03-10

CNC lathe machining is a high-precision, high-efficiency mechanical processing method that uses digital information to control the displacement of parts and tools on automated machine tools. Since CNC lathe machining completes all turning processes in one setup with continuous automatic processing, the following points should be noted during CNC lathe machining. 1. Pay attention to the selection of cutting parameters The three key elements of cutting conditions in CNC lathe machining are cutting speed, feed rate, and depth of cut, which can directly cause tool damage. As the cutting speed increases, the temperature at the tool tip rises, leading to mechanical, chemical, and physical wear. A 20% increase in cutting speed can reduce tool life by half. The impact of feed rate on tool wear is less than that of cutting speed, but a larger feed rate increases cutting temperature, resulting in greater tool wear. Although the depth of cut has less impact on the tool compared to cutting speed and feed rate, when cutting with a small depth of cut, the material being cut can produce a hardened layer, which can also affect tool life. 2. Pay attention to the selection of tools 1) For rough turning, choose tools with high strength and durability to meet the requirements of large back cutting amounts and high feed rates. 2) For finishing, select tools with high precision and durability to ensure the required machining accuracy. 3) To reduce tool change time and facilitate tool setting, try to use machine-clamped tools and machine-clamped inserts. 3. Pay attention to the selection of fixtures 1) Preferably use universal fixtures to clamp workpieces, avoiding the use of special fixtures; 2) Ensure that the positioning reference of the parts coincides to reduce positioning errors. 4. Pay attention to the selection of machining paths The machining path refers to the trajectory and direction of the tool relative to the part during the CNC lathe machining process. 1) It should ensure the required machining accuracy and surface roughness; 2) The machining path should be as short as possible to reduce the tool's idle travel time.

Basic Knowledge Required for Gear Design

2022-02-10

In mechanical design, the design of gears as mechanical elements requires essential technical knowledge. This is true even if you choose to use pre-designed gears. The knowledge of gears that needs to be mastered includes various calculation formulas used for gear strength and size calculations, types of gears, specialized terminology related to gears, gear pair speed ratios and directions of rotation, tooth profiles and tooth thickness, backlash, ISO and AGMA standards related to precision levels, assembly accuracy of gears, gear materials and heat treatment, hardness of gears, lubrication issues when using gears, strategies for noise and damage problems, geometric tolerances used in gear drawing, and special geometric symbols used in mechanical drafting.

Analysis of Errors Affecting the Contact Accuracy in Gear Processing

2022-01-04

The contact conditions of the gear tooth surfaces usually have a direct impact on the uniformity of load distribution in gear transmission. During rolling teeth, the main reasons affecting the contact accuracy in the tooth height direction are the tooth shape tolerance △ff and the base surface limit deviation △fpb. The main reason affecting the contact accuracy in the tooth width direction is the tooth direction tolerance △Fβ. The main causes of tooth direction tolerance are: 1. There is a parallelism error between the guide rail of the gear hobbing machine's tool holder and the rotation axis of the worktable. 2. The assembly deviation of the gear blank caused by the runout of the spindle and the non-parallelism of the bottom surface of the gear blank and the two end surfaces of the washer can lead to gear positioning errors. 3. When rolling helical gears, in addition to the aforementioned influencing factors, the calculation error of the machine tool's differential gears can also have a certain impact on the tooth difference of the gear.

Gears have a wide range of applications.

2021-12-20

The market application range of Shenyang gears is quite broad, but not every application area can utilize the core products of sprocket manufacturers. Only those fields that truly possess universal characteristics and have a large volume of sprocket applications hold practical investigation and research value. Currently, the core products suitable for application from sprocket manufacturers include: first, applications in transmission systems, commonly found in mechanized transportation tools and machinery. The main function in this field is to drive and relate to other aspects concerning speed, such as industrial gearboxes and vehicle wheel drive systems. Almost all systems that use sprocket products also require various types of gear products, and multiple mechanical devices and components must be optimized and matched to achieve the best sprocket application effect. If a sprocket experiences severe wear during use, it must be replaced or refurbished promptly. It is essential to use a certain amount of lubricating oil during daily operations to reduce wear. Additionally, sprocket manufacturers inform us that new sprockets should not be used together with old sprockets, as this can create a certain impact force and easily lead to breakage. Sprockets are transmission components and consumables that need to be replaced regularly to ensure the normal operation of equipment. When a sprocket needs to be replaced, the old sprocket must be removed and a new one installed, which requires professional personnel to operate. Sprocket manufacturers also provide corresponding installation and usage recommendations for different products to assist users during sprocket installation. Sprocket manufacturers process and produce different models and specifications of finished sprockets for various devices, with similar structural performance and installation methods. When purchasing sprockets, it is important to choose sprockets that match the equipment to ensure smooth installation and normal use.