What Sensors Are on The SMT machine?

1. Pressure sensor of SMT machine
Pick and place machine, including various cylinders and vacuum generators, have certain requirements for air pressure, lower than the pressure required by the equipment, the machine can not operate normally. Pressure sensors always monitor pressure changes, once abnormal, that is, timely alarm, remind the operator to deal with in time.

2. Negative pressure sensor of SMT machine
The suction nozzle of the SMT machine absorbs components by negative pressure, which is composed of negative pressure generator (jet vacuum generator) and vacuum sensor. If the negative pressure is not enough, the components will not be absorbed. When there are no components in the feeder or the components are stuck in the material bag and cannot be sucked up, the suction nozzle will not be absorbed. These situations will affect the normal operation of the machine. The negative pressure sensor always monitors the change of negative pressure, and when the suction or suction components are not available, it can give an alarm in time to remind the operator to replace the feeder or check whether the suction nozzle negative pressure system is blocked.

3. Position sensor of SMT machine
The transmission and positioning of printed board, including PCB count, real-time detection of SMT head and workbench movement, and movement of auxiliary mechanism, have strict requirements for position, which need to be realized by various forms of position sensors.

4. Image sensor of SMT machine
CCD image sensor is used to display the working state of the SMT machine in real time. It can collect all kinds of required image signals, including PCB position and device size, and make the adjustment and SMT of the patch head complete by computer analysis and processing.

5. Laser sensor of SMT machine
Laser has been widely used in SMT machine, it can help judge the coplanar characteristics of device pins. When run to the position of the laser sensor monitoring the device being tested, emitted by the laser beam into the IC pins and reflection to the laser on the reader, if the reflected beam length is the same as the beam, the device coplanarity qualified, if not the same, is due to become warped on pin, make the reflected light beam length, laser sensor to identify the device pin is flawed. Also, the laser sensor can identify the height of the device, which can reduce lead time.

6. Area sensor of SMT machine
When the SMT machine is working, in order to stick the head of the safe operation, usually in the head of the movement area is equipped with sensors, the use of photoelectric principle to monitor the operating space, to prevent damage from foreign objects.

7. Attach the pressure sensor of the film header
With the improvement of the speed and precision of the patch, the “suction and release force” of the patch head to attach the components to the PCB is increasingly required, which is commonly referred to as the “Z-axis soft landing function”. It is realized through the load characteristics of hall pressure sensor and servo motor. When the component is placed on the PCB, it will be vibrated at the moment, and its vibration power can be transmitted to the control system in time, and then fed back to the patch head through the control system’s regulation, so as to realize the z-axis soft landing function. When the patch head with this function is working, it gives a feeling of being smooth and light. If further observation is made, the depth of the two ends of the component immersed in the solder paste is roughly the same, which is also very beneficial to prevent the occurrence of “monument” and other welding defects. Without pressure sensor, there may be dislocation so as to fly.

SMT production line

Post time: Sep-07-2021