Tag: Speed Reducer

The reason for the unilateral meshing of the herringbone gear in the speed reducer

Some manufacturers frequently experience high-speed bearing overheating in their gear reducers during production, leading to poor gear meshing and unilateral meshing. Analysis suggests this is largely related to gear assembly and bearing selection. Herringbone gears require both end faces to be perpendicular to the axis, and the plane formed by the symmetrical center points of the two helical gears should also be perpendicular to the axis. However, errors can occur during actual machining and assembly. When an error-laden herringbone gear is assembled onto the shaft, the closed loop formed by the symmetrical center points of the left and right helical gears is not a plane perpendicular to the axis, but a curved surface. The rotation trajectory of this curved surface around the axis is two different curves. During operation, the symmetrical center lines of a pair of meshing gears must coincide. Therefore, the symmetrical center curves of this pair of herringbone gears will overlap and superimpose during gear meshing, inevitably resulting in peak-to-trough superposition, i.e., error accumulation…

Differences between hardened gearheads and soft and medium hardened gearheads

With the development of technology and the widespread application of computers, the world's transmission technology is trending towards the use of hardened gear reducers. Statistics show that the adoption of hardened gear reducers has reduced the weight and size of machines, continuously improved their quality, and increased their operating speed. Based on the hardness of the gear teeth, gear drives are generally divided into two categories: hardened gear drives and soft gear drives. Some also classify them into three categories, adding a third category: medium-hardened gear drives. Gear reducers with a working surface hardness greater than 350HB or 38HRC are called hardened gear reducers; those with a working surface hardness less than or equal to 280HB are called soft gear reducers; and those in between are called medium-hard gear reducers. The corresponding reducers are called hardened gear reducers, medium-hardened gear reducers, or soft gear reducers. Firstly, soft gear reducers, compared to hardened gear reducers, have always been the preferred choice for traditional domestic cranes due to their simple structure and relatively low price…

Cylindrical gear reducers have a wide range of applications and high cost performance.

Cylindrical gear reducers are a type of helical gear reducer, and they differ from hardened gear reducers. The main transmission mechanism of a cylindrical gear reducer consists of cylindrical gears, a sun gear, and an external gear ring. Cylindrical gear reducers are a widely used type of reducer, characterized by small structural size, high output torque, large reduction ratio, high efficiency, and reliable performance. The number of stages refers to the number of sets of cylindrical gears. Since one set of planetary gears may not be sufficient for a large transmission ratio, sometimes two or three sets are needed. This increases the length of a two- or three-stage reducer and reduces efficiency. Due to structural limitations, the minimum single-stage reduction of a cylindrical gear reducer is 3, and the maximum is generally no more than 10. Common reduction ratios are 3, 4, 5, 6, 8, and 10. The number of stages in a reducer generally does not exceed 3, but some custom-made reducers with large reduction ratios have up to 4 stages.

Failure Analysis of High-Speed ​​Gear Shaft Fracture in Gear Reducer

Speed ​​reducers have wide applications in industrial production, but high-speed gear shafts frequently break during use, even posing safety hazards. To address this issue, this paper first analyzes the factors contributing to high-speed gear shaft breakage from four aspects: material problems, inclusions within the shaft, assembly processes, and inadequate management. Finally, it discusses specific solutions from three aspects: selecting suitable products, further improving the installation process, and strengthening daily management and maintenance. Speed ​​reducers are common equipment in industrial production, widely used in coal mining, mechanical engineering, and other fields. Their application effectively improves production efficiency; however, high-speed gear shafts frequently break during use, leading to production disruptions. To avoid high-speed gear shaft breakage in speed reducers, the following…

Cylindrical gear reducer startup abnormal cause analysis

When a cylindrical gear reducer malfunctions, the first thought might be to call a professional repairman to disassemble and repair it. However, when a machine malfunctions, we can first perform a self-check. Listening to the sound can help determine the cause of abnormal vibrations and noise during startup of the cylindrical gear reducer. Let's hear what an experienced operator from a geared motor manufacturer has to say. Listening to the sound mainly involves checking for any abnormal noises from the bearings. We can buy a listening rod with a resonator at one end, or use a single metal rod to listen to the sound. Normal bearing noise in a cylindrical gear reducer is characterized by a continuous metallic sound without fluctuating pitch. A slight "excitement" sound is produced by the simultaneous rotation of the rollers or balls and the bearing raceway, containing irregular metallic sounds unrelated to the rotational speed. If this sound decreases or disappears after adding lubricating oil, it has no impact on operation. A cracking sound is caused by cracks appearing on the raceway surface of the bearing, or on the surface of the balls or rollers…

Factors affecting the price fluctuation of speed reducers

The price of each product in the market is determined by factors such as its performance, materials, and manufacturing process. Therefore, to understand the reasons for price fluctuations in speed reducers, the following aspects should be considered: 1. Currently, with the rise in steel prices, the price of speed reducers is also constantly increasing. Secondly, especially this winter, the supply of mains electricity is insufficient, and many northern regions have experienced power rationing, which has further increased its price. Thirdly, speed reducers are composed of many parts, and the assembly line process is complex, resulting in a relatively high overall manufacturing cost. 2. Even with the same generator brand and power output, attention must be paid to the difference in generators. Different generators will result in different performance characteristics of the speed reducer. Its performance is very important, so users must be cautious when purchasing it and can choose according to their needs…

Development of CAD/CAM system for cylindrical gear reducers

Cylindrical gear reducers feature high precision, high load capacity, high efficiency, long lifespan, low inertia, low vibration, low noise, attractive appearance, compact structure, and easy installation. They are suitable for independent transmission devices between the prime mover and the driven machine in agricultural machinery. A cylindrical gear reducer includes gears, shafts, bearings, and bearing ends. With the continuous improvement of CNC machining technology, the production trend of cylindrical gear reducers is towards automation, precision, and networking. Currently, the design of commonly used reducers still faces problems such as cumbersome design and large workload. Moreover, the machining of the main components of the reducer—gears, shafts, and housing—is mainly carried out using ordinary machine tools, resulting in relatively low design and production efficiency. The CAD/CAM system for cylindrical gear reducers is based on a visual programming language, Pro/EngineerWildfire software, and CNC machining simulation software VERICUT…

Emergency stop braking method for speed reducers

There are generally three methods for emergency braking of speed reducers: mechanical braking, regenerative braking, and reverse braking. Reverse braking offers the fastest braking speed. Below are the requirements for this braking method: 1. To effectively address the problem, it's necessary to understand the characteristics of the speed reducer's load and the specific requirements of its use. 2. The microcontroller-controlled motor drive circuit needs to have a power reverse function, such as a bridge circuit composed of four transistors or a forward/reverse circuit composed of relays. 3. When braking is required, the control circuit short-circuits to switch to motor reverse mode. When the motor speed drops to 0, power is cut off to reverse the circuit, and the motor stops. It's important to note that due to load variations, the time required for the reverse circuit to reduce the motor speed to 0 is not constant. Additionally, the speed reducer needs to be equipped with a speed sensor; otherwise, more complex control techniques, such as adaptive control, are required. You need to master these techniques for specialized applications…

How to choose the lubricant viscosity of the reducer

Viscosity is an important physicochemical indicator of gear oil. Choosing the correct gear oil viscosity reduces internal friction, thereby reducing wear on the gear surfaces of the reducer, as well as transmission noise and vibration. So, what is a suitable viscosity for lubricating oil? This question still troubles many users. Let's have a reducer manufacturer explain! 1. The viscosity of reducer lubricating oil is mainly achieved through base oil and viscosity index improvers. The viscosity of the base oil is related to its molecular structure and molecular weight; a higher average molecular weight results in higher viscosity. 2. A good viscosity index improver should have high thickening ability, good shear stability, and good low-temperature performance and thermal oxidation stability. 3. For lubricating oils of the same viscosity grade, if unrefined base oil and a poor-quality viscosity index improver are used, although a certain viscosity standard can be achieved through blending, the viscosity-temperature characteristics and shear stability will be poor, and the desired viscosity will not be met…

How to adjust the precision of the speed reducer?

Depending on the requirements for accuracy, transmission smoothness, and load distribution uniformity, the precision of a speed reducer can be divided into several grades. When the operating environment varies, we need to adjust its precision using the following methods: 1. Clearance Adjustment Method: During operation, the speed reducer generates friction, causing changes in the size, shape, and surface quality of related parts, resulting in wear and increasing the clearance between them. Adjustment is necessary to bring this clearance within a reasonable range to ensure the accuracy of the relative movement between parts. 2. Error Compensation Method: Proper assembly of parts can offset their inherent errors to a certain extent, ensuring the accuracy of the equipment's movement trajectory. 3. Comprehensive Compensation Method: Using the speed reducer's own installed tools to machine a correctly adjusted worktable surface eliminates the combined effect of various precision errors. In actual production, if using a ring…

Why does a speed reducer need a motor

A speed reducer changes speed by meshing gears of different sizes, inherently slowing down speed and increasing output torque. So why then is a motor needed? Many users likely have this question. To answer this, the speed reducer manufacturer provides the following explanation: The motor and speed reducer are paired to increase torque. When the load is high, simply increasing the power of the servo motor is inefficient. Therefore, a speed reducer with a suitable motor is selected within the required speed range. After passing through the speed reducer, the motor's output shaft speed is reduced, while its torque increases, meeting the operational requirements. Speed ​​reducers can be connected in two ways: one is a clamping method, where the servo motor's output shaft extends into the speed reducer and is connected via a flange. The speed reducer contains a deformable clamp; operating the locking screws allows the clamp to clamp the servo motor's shaft tightly. The other…

Meaning of the nameplate of the speed reducer

Many users request mechanical specifications when purchasing speed reducers. Do you know why these buyers ask this? What do these specifications mean? To help answer this question, the speed reducer manufacturer has provided a detailed explanation of their meaning. The speed reducer is mainly marked with information such as the model number, serial number, reduction ratio, service life, backlash, full-load efficiency, and rated torque. 1. Reduction Ratio: The ratio of the input torque to the output torque of the speed reducer. 2. Service Life: The cumulative working time of the machine at the rated input speed under rated load. 3. Backlash: With the input end fixed, and the output end rotated clockwise and counterclockwise, when the output end is subjected to a rated torque of ±21TP/3T, there is a slight angular displacement at the output end of the speed reducer. This angular displacement is the backlash. 4. Full-Load Efficiency: The transmission efficiency of the machine under high load conditions (output torque stopped due to fault). 5. Rated Torque…

Differences in design and selection methods between general-purpose and specialized reducers

The major difference between the design and selection methods for general-purpose and special-purpose speed reducers lies in their application. General-purpose speed reducers are suitable for various industries, but can only be designed for specific operating conditions. Therefore, users need to consider different correction factors based on their specific requirements, and factories should select based on the actual power of the selected motor (not the rated power of the speed reducer). Special-purpose speed reducers are designed according to the user's specific conditions. The necessary factors are generally already considered during the design phase. Selection only requires ensuring that the operating power is less than or equal to the rated power of the speed reducer, making the method relatively simple. The rated power of a general-purpose speed reducer is generally determined based on operating condition factors such as KA=1 (motor or turbine as the prime mover, stable machine load, 3-10 hours of operation per day, ≤5 starts per hour, and allowable starting torque twice the operating torque), contact strength factor SH≈1, and failure probability of a single gear pair ≈1%, etc.

Frequently Asked Questions about Worm Gear Screw Jacks

Worm gear screw jacks are widely used in various industries such as machinery, construction, chemical, and medical. They can accurately control and adjust the lifting or pushing height according to a certain program. They can be directly driven by an electric motor or other power source, or manually. Worm gear screw jacks may experience some common malfunctions during use. This article summarizes some common problems with worm gear screw jacks, hoping to be helpful. Wear of the transmission helical gear. This usually occurs in vertically installed reducers, mainly related to the amount of lubricating oil added and the choice of lubricating oil. In vertical installations, insufficient lubricating oil is easily caused. When the reducer stops running, the transmission gear oil between the motor and the reducer leaks out, and the gears do not receive the necessary lubrication protection. Ineffective lubrication during startup or operation leads to mechanical wear or even damage. Worm gear wear. Worm gears are generally made of tin bronze, and the mating worm is generally made of 45 steel hardened to HRC45-5…

Fatigue analysis of hardened gear reducers

Hardened gear reducers are widely used in the light textile machinery processing industry, and in recent years, metallurgical enterprises have also gradually adopted them, particularly in raw material belt conveyor processes. However, their use as main reducers in rolling mills is still relatively rare. Therefore, the load-bearing capacity of reducers is limited not only by mechanical strength and allowable thermal balance power, but also by the operation of the rolling mill and harsh environments. When selecting this type of reducer, the influence of environmental factors, temperature, and variable loads should be considered. The rack fatigue fracture occurred in the low-speed gear pair. Observation of the entire gear meshing situation (taking an incident in January 1997 as an example) revealed that the meshing gears exhibited large-area pitting corrosion due to contact fatigue failure, with dense spots and individual pits 10-15mm wide. Two intermediate transition gear shafts (numbered 1 and 2) and two low-speed shaft large gears (numbered 3 and 4) also detached. Observation of the fracture of the four detached racks…

What do you know about worm gear reducers?

Worm gear reducers are a type of transmission machinery characterized by their compact structure, large transmission ratio, and self-locking function under certain conditions. They are one of the most commonly used reducers. But what else do you know about worm gear reducers? When using a new reducer, the oil needs to be changed after 300 hours of continuous operation, and then every 2500 hours thereafter. However, the oil quality should still be checked regularly during use. If the oil contains impurities, is aged, or deteriorates, it must be replaced immediately. Reducers should use gear oil of a fixed brand and grade; different brands, grades, or types of oil should not be mixed. During oil changes, the inside of the reducer should be thoroughly cleaned before adding new oil. During use, if the oil temperature is found to be too high (above 80℃) or abnormal noise is observed, use should be stopped immediately, and the cause investigated. Use can only resume after the fault has been rectified or the lubricating oil changed. In extremely cold conditions such as -1…

The role of speed reducers in increasing output torque

Common speed reducers include helical gear reducers (including parallel shaft helical gear reducers, worm gear reducers, bevel gear reducers, etc.), planetary gear reducers, cycloidal pinwheel reducers, worm gear reducers, planetary friction reducers, continuously variable transmissions (CVTs), etc. Less common types of speed reducers include: 1. Worm gear reducers: A key characteristic is their reverse self-locking function, allowing for a large acceleration ratio. The output and input shafts are not on the same axis or in the same plane. However, they are generally large in size, with low transmission efficiency and low precision. 2. Harmonic reducers: Harmonic transmission utilizes the controllable elastic deformation of flexible elements to transmit motion and power. They are small in size and have high precision, but their drawbacks include unlimited lifespan of the flexible gear, poor impact resistance, and lower rigidity compared to metal parts. The output speed cannot be too high. 3. Planetary reducers: Their advantages include a relatively compact structure, small backlash, high precision, long service life, and high rated input torque…

How to solve the wear problem of worm gear reducers?

A worm gear reducer is a power transmission mechanism that uses a gear speed converter to reduce the rotational speed of a motor to a desired speed and obtain a larger torque. Next, we'll discuss how to handle worm gear reducers, hoping this will be helpful. The worm wheel is generally made of tin bronze. During normal operation, the worm acts like a hardened "file," constantly grinding against the worm wheel, causing wear. Generally, this wear is slow; some reducers from certain manufacturers can last for over 10 years. If the wear rate is faster, consider whether the reducer selection is correct, whether it's being overloaded, the material of the worm wheel, assembly quality, or the operating environment. This often occurs in vertically mounted reducers, mainly related to the amount and type of lubricating oil. In vertical installations, insufficient lubricating oil is easily caused. When the reducer stops running, the transmission between the motor and the reducer…