① The transmission is stable, the working ratio is instantaneous and stable, and the transmission is accurate and reliable, which can convey any movement in space and the power of two rods; Power and speed range
② Wide application scope;
③ The diffusion movement efficiency is high, = 0.92 0.98;
④ Reliable operation and long service life;
⑤ Small size and compact structure. A gear, which is composed of: ; The reducer, which consists of gears, shafts, bearings and boxes, is used for prime movers, working machines or actuators. It has the functions of fast rotation and transmission, and is widely used in modern machinery.
⑥ Most of the local reducers are gear transmission and rod transmission, but there is a common problem that the ratio of power to weight is small or the transmission ratio is large and the machine efficiency is low. There are also many weaknesses in material and process level, and the problem of oversize reducer is more prominent and its service life is not long. In foreign countries, Germany, Denmark and Japan are in the leading position, especially in materials and manufacturing technology, and the reducer works reliably and has a long service life. However, its transmission form is still dominated by fixed axle wheel transmission, and the problems of volume and weight cannot be solved.
Nowadays, the speed reducer is developing in the direction of high power, large transmission ratio, small volume, high mechanical efficiency and long service life. The connection between the reducer motor and the motor body structure is also a strong development form, and products of various structural forms and power models have been produced. In recent ten years, due to the development of modern computer technology and digital control technology, the machining accuracy and efficiency of the machine have been greatly improved, which has promoted the diversification of movable goods spread by the machine, and the modularization, standardization and artistic design of the whole machine have made the products more refined and beautiful.
In the middle of 2 1 century, gears are still the basic parts of machine transmission. The development of CNC machine tools and technology has promoted the rapid development of machine tool transmission structure. Under the electronic control of transmission, the liquid in the system is designed as a hybrid transmission of pressure transmission, gear transmission and belt chain, which will soon become the best transmission direction combination in the box design. Being at the intersection of communication design disciplines will become an important trend in the development of new communication movable articles.
Basic features: reduction gear, bearing, gear and mechanical transmission.
abstract
Gear transmission is the most widely used transmission form in modern machinery. Its main advantages are:
① The instantaneous transmission ratio is constant, the work is stable, the transmission is accurate and reliable, and the motion and power between any two axes in space can be transmitted;
(2) wide range of power and speed;
③ High transmission efficiency = 0.92.0.98;
④ Reliable operation and long service life;
⑤ Small external contour and compact structure. The gear reducer, which consists of gears, shafts, bearings and boxes, is used between the prime mover and the working machinery or executing mechanism to match the rotating speed and transmit the torque, and is widely used in modern machinery.
Gear drive and worm drive are the main types of reducers in China, but there are widespread problems such as low power-to-weight ratio or large transmission ratio and low mechanical efficiency. In addition, the material quality and technical level also have many weaknesses, especially the large reducer, which has a short service life. Foreign reducers are in a leading position, especially in materials and manufacturing technology, with good reliability and long service life. However, their transmission form is still fixed shaft gear.
Today's reducer is developing towards high power, large transmission ratio, small volume, high mechanical efficiency and long life. The conjoined structure of reducer and motor is also a form of great development, and products of various structural forms and power models have been produced. In recent ten years, due to the development of modern computer technology and numerical control technology, the machining accuracy and efficiency have been greatly improved, thus promoting the diversification, modularization and standardization of mechanical transmission products and the modeling design of the whole machine.
In the complete set of mechanical equipment in 2 1 century, gears are still the basic components of mechanical transmission. The development of CNC machine tools and technology has promoted the rapid development of mechanical transmission structure. The hybrid transmission of electric control, hydraulic transmission, gear and belt chain in transmission system design will become the direction of optimizing transmission combination in gearbox design. The intersection of transmission design disciplines will become an important trend in the development of new transmission products.
Keywords: mechanical transmission reducer bearing gear
abstract
One of the contents of this graduation project is about the design of complete reducer system.
Deceleration machine is an independent and complete mechanism that moves out of the rigid gear near the hull. Through this design, we can master a complete set of design steps and methods of general simple machines.
This graduation project introduces the type, function and composition of reducer. Mainly use everything. Learn knowledge directly. Such as: mechanical drawing, metal material technology, business travel and other theoretical knowledge. In actual production, the analysis is sure to reach an agreement. The general types of reducers are: cylindrical gear reducer, bevel gear reducer, gear reducer, spiral rod reducer, rod reducer, assembled reducer, combined reducer and combined reducer.
In this design, the independent ability of engineering design is further cultivated, the correct design idea is established, the methods and steps of common mechanical parts, mechanical transmission devices and simple mechanical design are mastered, and the requirements of comprehensive application of economic technology are required. Determine a reasonable design scheme.
Keywords: reducer rigid technical components/zero porat
Percentage/item
abstract
This graduation project is an independent and complete institution driven by all the contents enclosed in a rigid shell. Through this design, we can master a set of design and methods of general simple machinery, and form the general parts of reducer.
This graduation project mainly introduces the types, functions and components of reducers, and comprehensively uses the learned knowledge, such as mechanical drawing, metal material process tolerance, etc., to analyze and solve the learned theoretical knowledge in actual production. The general types of reducers are: cylindrical gear reducer, bevel gear reducer, worm gear reducer, shaft reducer, assembled reducer, shaft reducer and conjoined reducer.
In this design, we should further cultivate the independent ability of engineering design, establish correct design ideas, master the methods and steps of common mechanical parts, mechanical transmission devices and simple mechanical design, and comprehensively consider the requirements of using economy and technology to determine a reasonable design scheme.
Keywords: reducer rigid process parts scheme
Compared with ordinary gear reducers, planetary gear reducers have the advantages of small size, light weight, high efficiency and large transmission power range, and are gradually being widely used. At the same time, its disadvantages are: complex material, high manufacturing accuracy, difficult installation, and more complicated design and calculation than the general reducer. However, with the further understanding and understanding of planetary transmission technology and the introduction and absorption of foreign planetary transmission technology, its transmission structure and containment mode are also constantly improving, and the production technology level is constantly improving, so as to produce better planetary reducers.
According to the general load, the design and calculation of gear strength and geometric size are carried out, and then the design and calculation of transmission ratio, concentricity, assembly and adjacent conditions are carried out. Because of the large number of planetary gear drives, the design and calculation of the mechanism and floating volume must also be carried out.
According to the basic components, planetary gear transmission can be divided into three types: 2KH, 3K and KHV. According to the meshing mode of gears, they can be divided into NGW type, NN type, WW type, WGW type, NGWN type and N type. The planetary gear I designed is 2KH NGW planetary transmission type.
Compared with ordinary gear reducers, planetary gear reducers have the advantages of small size, light weight, high efficiency and large power transmission range, and have gradually been widely used. At the same time, its disadvantages are: high material quality, complex structure, high requirements for manufacturing accuracy, difficult installation and complicated design and calculation. However, with the further understanding and mastery of planetary transmission technology and the introduction and digestion of foreign planetary transmission technology, its transmission structure and load sharing mode have been continuously improved, and the production technology level has been improved.
According to the load situation, design and calculate the strength and geometric dimensions of general gears, and then design and calculate the transmission ratio conditions, concentricity conditions, assembly conditions and adjacent conditions. Because multiple planetary gears are used, it is necessary to design and calculate the load-sharing mechanism and floating amount.
According to the composition of basic components, planetary gear transmission can be divided into three types: 2KH, 3K and KHV. According to the meshing mode of each pair of gears, it can be divided into NGW type, NN type, WW type, WGW type, NGWN type and N type. The planetary gear I designed is NGW 2KH planetary transmission.
● What is a ball screw?
In this way, the movement of objects, generally speaking, needs to generate power, which is directly or indirectly transmitted to the final movement department through other organizations. In the case of automobile, the gasoline engine, because the combustion piston moves up and down, is finally transmitted to the wheel through the intermediary, making it rotate.
In today's world, all kinds of sports organizations that can represent machinery and plants can be said to have some form of sports transmission mechanism without exception. Ball screw is the most reasonable product to convert rotary motion into linear motion or linear motion into rotary motion.
● Ball screw specialty
1, compared with the sliding torque of ball screw 1/3.
Because there is a lot of ball rolling motion between the screw shaft and the screw nut of the ball screw, this motion can obtain higher efficiency. Compared with the last time, the driving torque of sliding ball screw is below 1/3, which means that rolling ball screw 1/3 is needed to achieve the same dynamic motion effect. Help to save.
2, high precision guarantee
Ball screw is made of the highest level of consistency in the world of machinery and equipment from Japan and Germany, especially in the factory environment and temperature of research and cutting, assembly and inspection of various procedures. The humidity is strictly controlled by the quality management system, so that the accuracy is effectively guaranteed.
3. Micro-feed can
Because the ball screw uses ball motion, the starting torque is very small, and there will be no crawling phenomenon, and the sliding motion can ensure accurate micro-feed.
4, no backlash, high rigidity
The ball screw can apply pressure, because the pressure in the axial gap can reach a negative value, and then a higher stiffness can be obtained (in the practical mechanical device, the ball screw applies pressure through the ball, because the repulsive force of the ball can increase the stiffness of the nut).
5. High-speed feed is possible
Ball screw has high movement efficiency and low calorific value, so it can realize high-speed feeding (movement).
● What is a ball screw pair?
When moving an object, it is generally necessary to transfer the motion generated by power directly or indirectly through other mechanisms to the final moving parts. Taking an automobile as an example, due to the combustion of gasoline in the engine, the piston moves up and down, and then it is finally transmitted to the wheel through the intermediate mechanism to make it rotate.
In today's world, devices that can represent machinery and have various motion mechanisms can have some form of motion transmission mechanism. Ball screw pair is the most reasonable product to convert rotary motion into linear motion or linear motion into rotary motion.
● Characteristics of ball screw pair
1, compared with the sliding screw pair, the driving torque is 1/3.
Because there are many balls rolling between the screw shaft and nut of the ball screw pair, high movement efficiency can be obtained. Compared with the sliding screw pair in the past, the driving torque is below 1/3, that is, the power required to achieve the same motion result is 1/3 of that of the rolling screw pair. This is very helpful for saving electricity.
2, the guarantee of high precision
Ball screw pairs are produced by the world's highest level mechanical equipment made in Japan, especially in the factory environment of grinding, assembly and inspection, and are very sensitive to temperature? The humidity is strictly controlled, and the perfect quality management system fully guarantees the accuracy.
3. Micro-feed possibility
Because the ball screw pair adopts ball motion, the starting torque is very small, and there will be no crawling phenomenon like sliding motion, which can ensure accurate micro-feed.
4, no backlash, high rigidity
The ball screw pair can be pre-stressed, because the pre-stress can make the axial clearance reach a negative value, and then obtain a higher stiffness (when the ball screw is actually used in mechanical equipment, the stiffness of the female part can be enhanced due to the repulsive force of the ball).
5. High speed feed is possible.
The ball screw pair has high movement efficiency and low calorific value, and can realize high-speed feeding (movement).