1. Key points of drive station design
The drive station is the power core of the accumulation and release chain conveyor line. First of all, the appropriate motor should be selected according to the load requirements and running speed of the conveyor line. For conveyor lines with large loads and low speed requirements, asynchronous motors with large torque can be selected; for conveyor lines with high precision and high speed, servo motors may be more suitable. The power calculation of the motor should take into account the total weight of the chain, trolley and goods, and factors such as inertia force at startup and friction during operation should also be taken into account. For example, the motor power can be preliminarily estimated by the formula $P=Fv/η$ (where $P$ is power, $F$ is total traction, $v$ is running speed, and $η$ is transmission efficiency).
The selection of the reducer of the drive station is also critical. It is used to match the output speed of the motor and the running speed of the chain. The reduction ratio of the reducer should be determined according to the rated speed of the motor and the required linear speed of the chain of the conveyor line. In addition, the meshing of the drive sprocket and the chain should ensure good accuracy, and the number of teeth and pitch of the sprocket should match the chain to ensure effective power transmission. Generally speaking, the number of teeth on the sprocket is designed to be an even number, which is conducive to uniform wear of the chain. At the same time, in order to prevent the chain from jumping teeth during the start and stop process, the drive station should also be equipped with a braking device, such as an electromagnetic brake, to achieve fast and smooth start and stop control.
2. Importance and type selection of tensioning device
The tensioning device is a key component to ensure the normal operation of the accumulation and release chain conveyor line. It can compensate for the elongation of the chain during operation and prevent the chain from loosening. Common tensioning devices are heavy hammer type, spring type and hydraulic type. The heavy hammer type tensioning device has a simple structure and high reliability. The gravity of the heavy hammer keeps the chain at all times. The chain maintains proper tension, but it is large in size and occupies more space. The spring type tensioning device uses the elastic deformation of the spring to absorb the elongation of the chain. Its tension is relatively stable and occupies less space. It is suitable for occasions with limited space. The hydraulic tensioning device can provide precise tension control and can be adjusted according to actual working conditions, but the cost is high. It is often used in high-precision conveyor lines with high tension requirements.
3. Installation location and parameter design of tensioning device
The tensioning device is generally installed in the return section of the conveyor line, close to the drive station or at the end of the conveyor line. The choice of installation location should be considered to facilitate observation and adjustment of tension. When designing the parameters of the tensioning device, the first thing to do is to determine the appropriate tensioning stroke. The tensioning stroke should be determined according to the elongation of the chain, which is generally 1.5-2 times the pitch of the chain. For example, for a chain with a pitch of 50mm, the tensioning stroke can be designed to be 75-100mm. The size of the tensioning force should be determined according to the working tension of the chain, which is generally 1.2-1.5 times the working tension of the chain to ensure that the chain has sufficient tension during operation, while not increasing the wear of the chain and sprocket due to excessive tension.
4. Collaborative work of drive station and tensioning device
The drive station and tensioning device are interrelated and work together in the accumulation and release chain conveyor line. At startup, the drive station provides power to move the chain. At this time, the tensioner must be able to respond to the dynamic changes of the chain in time to ensure the stability of the chain tension. For example, when the chain suddenly accelerates, the tensioner must be able to compensate for the instantaneous elongation of the chain to prevent the chain from slackening and jumping teeth. During operation, the operating speed and output torque of the drive station will affect the tension of the chain, and the tensioner balances this change by adjusting the tension. At the same time, the tensioner can also provide a certain preload for the chain to help the drive station better transmit power and ensure that the accumulation and release chain conveyor line can operate efficiently and stably. In order to achieve good synergy between the two, the mechanical connection between them and the linkage of the control system should be considered during the design, so that the drive station and the tensioner can automatically adjust according to the actual working conditions of the conveyor line to achieve the best working state.
