As the fundamental industry of China's economic development, the development of the machinery manufacturing industry is also further improving through continuous accumulation, and its current development is stable. There are various types of mechanical equipment, and their movement modes and functions are also different. Some mechanisms are relatively small and flexible, while others are relatively thick and cumbersome, but they cannot be separated from their roots. In the construction of machinery, power transmission has undergone a gradual evolution from the ancient mechanical method to the extensive use of electric, pneumatic, and hydraulic transmission today, which has not only brought about changes in power efficiency, It also makes it possible to accurately control the movement of mechanical structures during processing, making the ideal digital and automated processing method possible. Below, I will share with you the advantages and disadvantages of three common mechanical transmission methods.
gear drive
Gear transmission is the most widely used transmission form in mechanical transmission. The gear transmission is relatively accurate, with high efficiency, compact structure, reliable operation, and long service life. Gear transmission can be divided into many different types according to different standards.
Advantages: Compact structure, suitable for close transmission; Wide range of applicable circumferential speed and power; Accurate, stable and efficient transmission ratio; High reliability and long service life; It can realize transmission between parallel shafts, arbitrary angle intersecting shafts, and arbitrary angle staggered shafts.
Disadvantages: High manufacturing and installation accuracy and high cost are required; Not suitable for long-distance transmission between two shafts; No overload protection.
worm drive
Worm gearing is used to transmit motion and torque between two spatially staggered shafts. Movement can be deceleration or acceleration, and the most commonly used is the angle of intersection Σ= 90 ° reduction drive. The helix direction can be either right-hand or left-hand, but the helix direction of the worm and the worm gear must remain the same. Traditionally, right-handed is preferred.Disadvantages: Large axial force, easy to generate heat, low efficiency, and only one-way transmission.
Planetary gear transmission
A gear train is a transmission system composed of a series of wheels. These wheels are usually gears or friction wheels. According to whether the geometric axis of each gear in a gear train is fixed, it can be divided into fixed shaft gear trains and planetary gear trains. Gear transmission can be divided into ordinary gear transmission and planetary gear transmission based on whether there are gears with axial movement in the gear train. Gears with axial movement in the gear train are called planetary gears.
1. Gear trains are divided into fixed axle gear trains and epicyclic gear trains.
2. The ratio of the angular velocity or rotational speed of the input shaft to the output shaft in a gear train is called the transmission ratio of the gear train. Is equal to the ratio of the product of the number of teeth of all driven gears in each pair of meshing gears to the product of the number of teeth of all driving gears.
3. In a epicyclic gear system, a gear with a variable axis position, that is, a gear that rotates both autonomously and circumferentially, is called a planetary gear, while a gear with a fixed axis position is called a central wheel or a sun gear.
4. The transmission ratio of an epicyclic gear train cannot be directly calculated using the method of solving the transmission ratio of a fixed shaft gear train. Instead, the principle of relative motion must be used to convert the epicyclic gear train into an imaginary fixed shaft gear train using the relative velocity method (or the reverse rotation method) for calculation.
Advantages: Suitable for transmission between two shafts that are far apart; It can be used as a transmission to achieve variable speed transmission; Large transmission ratio can be obtained; Realize the synthesis and decomposition of motion.
Source: Furong Transmission
