Why do PCBs need to be stencilled? PCBs are assembled to meet production requirements. Some PCB boards are too small to meet the fixture requirements, so they need to be assembled together for production. In order to improve the soldering efficiency of SMT. Only need to pass through the SMT once to complete the soldering of multiple PCBs. In order to improve cost utilization. Some PCB boards are shaped, so assembling PCB boards can utilize the PCB board area more efficiently, reduce waste and improve cost utilization.
PCB Imposition Method
- CNC+V-CUT Imposition
The gong board with V-cut is suitable for boards with devices on the board edges, which can’t be assembled without spacing, and adopt the form of assembling with process edges. Add process edge V-CUT processing at both ends, leaving spacing in the middle of the gong to facilitate the welding of components, otherwise the devices on the edge of the board interfere with each other and can not be assembled and welded.
- Stamp hole bridging collation
Stamp holes are a kind of bridge way of collation, stamp holes bridge can solve the V-CUT bridge can not solve the problem, such as round plate, irregular plate can not V-CUT can only take the stamp holes connected to collation.
- V-CUT bridge piecing
V-CUT bridge collocation for regular boards, because the V-CUT machine is to walk a straight line, so the V-CUT knife can not turn only V-CUT straight. So the V-CUT position must be a straight line to V-CUT, there is a point to note that components near the edge of the board position can not be platen V-CUT, it willaffect the assembly welding.
4. No Process Edge Plating
In order to save the utilization rate of small boards, often do not add process edges, but pay attention to the location of the V-CUT can not have components in the board edge, components near the edge of the board, it is best to add process edges to leave the spacing of the board, otherwise, it will affect the assembly of the components and the weldability.
Real case of components sticking out of the board and not being able to be assembled.
Component interference due to unpitching
Problem description: PCB board component package silkscreen design beyond the board edge, due to lack of attention in the board assembly, unpitched board layout leads to component interference, affecting the SMT mounting.
Impact of the problem: beyond the board edge of the device without spacing board can not be assembled, affecting the product development cycle, if you want to find a way to assemble, next to the spacing of the assembly of one half of the assembly is not assembled, but also lead to half of the product will be scrapped.
Problem extension: devices beyond the edge of the board without spacing collocation, in the case of barely plug-in, plug-in after the split board will also lead to component damage, resulting in greater cost losses.
After the PCB drawing design is completed, use the assemblability checking tool to check, which can avoid the problem that the components on the board edges can not be assembled. The assembling tool can meet the user’s personalized assembling needs.
