PCBA Tech - Some electromechanical parts in smt placement machine

1. Filter

The filter filters the compressed air used in smt patch proofing or processing to ensure the cleanness of the cavitation gas. If the filter is dirty and the filtering effect is not good, it will affect the suction of the nozzle and directly affect the patch effect. In equipment maintenance, the filter is required to be replaced regularly, generally once a month, which is a consumable item. Therefore, certain spare parts must be available.

2. Reflector and reflective cap

The reflector is used to detect the component size, component electrode and nozzle number. When the above three types of poor recognition occur during the patching process, the reflector and reflector cap must be inspected or replaced.

3. Conveyor belt

The conveyor belt is used to convey smt products. The conveyor belt will wear out during long-term use, and will break after a certain period of time, so it needs to be replaced. At least 1 spare part is required, and there may be 2 spare parts for frequently worn parts.

4. Cylinder

Cylinders are generally used in combination with solenoid valves in the placement machine, and play the role of lifting and stopping. In the placement machine mechanism, the air cylinder is widely used. For example, the air cylinder used on the placement head can set whether the placement head is used or not, and stop the action; when the placement table rises and falls, the air cylinder performs according to the signal of the solenoid valve. The expansion and contraction causes the workbench to rise and fall. There will be wear and dust in the cylinder during use. The editor recommends that you should check regularly and deal with problems in time. If the cylinder is not flexible or not in place due to unclean compressed air, it must be cleaned. If the air leaks, It is possible that the sealing ring is aging. Replace the sealing ring. If the piston is worn out, replace the cylinder.

5. Bearing

The role of the bearing has two aspects, the first is the limit, the second is the support. Bearing limit means that the fixed shaft can only achieve rotation, but cannot move in the axial and radial directions; support means to bear the radial load of the shaft. Bearings are classified into rolling axial bearings, ball bearings and thrust bearings according to their functions.

Bearings are widely used standard parts in the structure of placement machines. They require stable operation. If they are operated for a long time, they will be worn. Regular inspections should be carried out. If the bearings are found to have radial movement, which affects the normal operation of the equipment, they must be carried out in time. replace. Such as joint bearings and rolling bearings used in placement machines.

6. Synchronous belt

The synchronous belt transmission is composed of an endless belt with equidistant teeth on the inner peripheral surface and wheels with corresponding anastomosis. It combines the advantages of belt drive, chain drive and gear drive. When rotating, power is transmitted through the meshing of the belt teeth with the tooth grooves of the wheel. The synchronous belt drive has an accurate transmission ratio, no slip, and a constant speed ratio can be obtained. The transmission is stable, it can absorb vibration, has low noise, and has a large transmission ratio range, generally up to 1:10, and allowable linear speed up to 50m/s. The transmission power ranges from a few watts to hundreds of kilowatts. High transmission efficiency, generally up to 98%, compact structure, suitable for multi-axis transmission, no lubrication, no pollution, so it can work normally in places where pollution is not allowed and the working environment is relatively harsh.

On the smt placement machine, the timing belt is generally used for the rotation of the θ angle and the transmission of the main shaft. It will be worn for a long time and needs to be checked and replaced regularly to ensure the normal operation of the equipment.