PCBA Tech - Turret type smt placement machine single

Consider the case of the feeder position optimization of the turret type smt placement machine. The turret feeder and the feeding table are mainly based on each moving station. The component position is placed in order from the first position of the material station, and according to The component categories are arranged. The simpler, the smaller, the easier to identify the components, sorted in the front; the more complex, the larger the components are placed in the back. That is, the fastest component placement speed is placed first, and the slowest placement speed is placed second. Moreover, the same type of components at the same speed are arranged together. The editor of Zhongyan Electronics suggests that it is best to have only one type of component for a machine to maintain the consistency of the rotation speed of the machine's placement head. In the sorting of the same type of components, the component closest to the origin coordinate on the printed board is arranged in the first position of the material station; among the remaining components, look for the position closest to the last component placed in the first feeder The components are installed in the second material station, and so on. Turret machines can be arranged regardless of the number of components.

The reason for this regulation is due to the smt mounting characteristics of the turret equipment.

1. The movement characteristics of the turret crane feeding table. When the placement machine is working, the patch nozzle picks up a component at a fixed position, the placement head rotates to make the other nozzle rotate to a fixed position, and at the same time the feeding table moves to make the next specified component reach the fixed position, the nozzle Pick up the next component. The picking interval of the two components is fixed, which is determined by the rotation speed of the placement head (such as 0.1s/chip). If the feeding table moves another component to a fixed position within the interval time, the maximum speed of the machine can be guaranteed. If the moving position span is too large and the time required exceeds the picking interval time, the placement head will wait, and the entire machine There is no guarantee of maximum efficiency. In addition, when the feeding station is moving, move a feeding station, and the feeding station will move at the maximum speed. When the position of one feeding station is exceeded, the moving speed will be reduced to only 70% of the maximum speed. Therefore, it is necessary to minimize the number of round trips between the feeder stations that are far away from each other.

2. The faster the rotation speed of the turret, the faster the placement. Get the fastest rotation speed placement. However, the actual maximum rotation speed of the placement head is affected by the size, accuracy and complexity of the shape of the component. The smaller the component, the simpler the shape and the easier it is to identify the component, the faster the placement head rotates; the larger the component, the more complex the shape, and the slower the placement. If a large component is mounted too quickly, it is easy to fly the component due to insufficient vacuum suction during the rotation process, or the component displacement causes the mounting accuracy to be inaccurate; the more complex the component shape, the different component recognition method, and the longer the recognition time. The rotation speed of the placement head becomes slower. In the actual smt patch proofing or processing production process, the rotation of the machine is basically a fixed number, and it is impossible to set different speeds for large and small components. Constant acceleration and deceleration will cause the prolongation of the production cycle and the instability of the movement, which will affect the production. Efficiency and quality. Generally, the machine moves at the slowest speed among all the component placement components. Therefore, the position of the feeder is arranged according to the category, and the same type of components at the same speed are arranged together.

3. Movement distance of X-Y worktable. Like the movement of the material station platform, when the pick-and-place head nozzle is already in the placement position, because the worktable has moved too much and the printed board has not moved to the relevant position, the placement head will also wait, which affects the placement time. The placement position optimization generally adopts the shortest path principle. In the process of mounting components, the machine looks for the shortest placement path, so that the printed board table moves the least distance and the machine waits for the least time.