What is the purpose of the surface roughness mounter?

What is the purpose of the surface roughness mounter?
There are many different types of placement machines (also known as pick and place machines). This market aims to place electronic components on the surface of printed circuit boards as accurately and quickly as possible
With the addition of the available electronic component types, the functions of these machines have also been added. Some machines are specially designed for speed, while others pay more attention to flexibility. It is very important to select the placement machine according to the product type. important
Machines designed to increase speed are often referred to as "super high speed placement machines", where parts can be placed at speeds up to 100,000 cubic feet per hour (parts per hour). The flexible placer can handle connectors ranging from 01005 to 150 mm, and can check/place miniature BGI (ball grid array) and power factor (package to package) equipment.
The general concept is to send the printed circuit board printed with solder paste to the placement machine, and then transport it to the placement area through the conveyor belt and clamp it. Then, the machine vision system uses the reference mark to confirm the fixed position of the PCB and starts the electronic component placement program.
Circuit board

The part placement process involves using a nozzle to pick up each part from the feeder in turn and transport it to the programmed location.
Each type of mounter has its own program format, but all contain the same information, including part number, circuit board reference, rotation, packaging information, and X year/year location.
After assembly, loosen the parts and transport them to the next workbench on the production line through the conveyor belt
In order to achieve the reliability of the mounter, the following points need to be considered:
·PCB design
1. Panel size
2. Treatment belt
3. Datum mark
4. Component size and location
·Nozzle
·Visual system
·PCB support
·How to provide components
PCB design
The design of printed circuit board and the panel pipe of printed circuit board will affect the component placement process. The following is a list of precautions:
·Panel Size All machines have a specified maximum and minimum panel size that can be machined.
·Handling adhesive tape When designing printed circuit boards, it is common to place components near the edges. This is because of the processing mechanism of PCB in various machines, it is very important to panel PCB.
·Datum marks Datum marks are simple shapes in the tracking layer of the printed circuit board. The positions of these shapes should not be confused with other aspects of the circuit board design
The placement machine vision system uses reference marks to ensure that all components are correctly positioned. When aligning the PCB with the machine, it is recommended to use the farthest reference point to achieve maximum accuracy, and it is recommended to use 3 reference points to determine whether the PCB has been correctly loaded.
·Assembly Size and Location - Large overall designs may place smaller assemblies close to larger assemblies, which need to be considered when generating placers. All smaller components need to be placed in front of larger components to ensure that they are not disturbed. Placement of program optimization software usually takes this into account.
Nozzle
With the increasing number of surface mount components available on the market, there are also many different types of nozzles available. Most nozzles use vacuum to hold the part firmly between the pick and place steps, but this does depend on the flat top surface of the part. Another option is the gripper nozzle, which clamps the side of the assembly and uses vacuum to drive the mechanism.
It can be specified that the top of some parts (such as connectors) is not flat, and pads/pieces that can be vacuum picked and placed can be purchased from suppliers.
It is important to select the correct nozzle for each different part to be placed to ensure accurate and consistent placement Select the following
It is important to check the nozzle regularly for problems, such as solder paste contamination, as shown below. During picking and placing, this may cause parts to stick to the nozzle and lead to defects such as missing or misplaced parts
Visual system
Before placement, the machine vision system analyzes each picked component to ensure that all programmed parts match in size and check for damage, such as bent wires. It is important to program each component with the correct tolerance parameters, so that the machine can determine whether the incorrect parts are loaded and will not reject acceptable parts
PCB bracket
Most printed circuit boards are made of fairly hard 1 6mm FR4 data, but when using thinner data or slots, this will be a challenge for PCB holders During component placement, this may lead to inconsistent results, because if the printed circuit board is not fully supported, there will always be some placement pressure and it will bend Setting up support can be time-consuming. In retrospect, you can see many self tuning systems available here Flexible support systems can not only be built quickly, but if the two-sided modules are built with modules already installed on the lower side, these factors should also be considered Here are two of the most common solutions for shaping yourself around placed components
How to provide components
Surface mounted components are supplied with a variety of pipes, the most common being tape/reel, pipe and tray. All machine manufacturers have feeders in this package, but problems occur when only a few parts are needed for small batch assembly. In this case, components are usually provided in pipes that cannot be directly loaded into the machine. In fact, they are either sent to the above packaging or placed manually. Neither is ideal, because they are expensive and time-consuming. The quality problem of spending too much money.
For components provided in the form of adhesive tape, if only a small amount is needed, there are many available "short belt" feeding methods that can be used as pallet loading.