Design Of An Automatic Sorting Device For Ceramic Substrate Based On MCU

PTCR is a kind of semiconductor material with large positive temperature coefficient.When the temperature is above a certain limit, its resistance value will increase rapidly,according to the temperature rise. The main functions of PTCR include automatic demagnetization, delaying start, over-current protection, constant overheating protection.With the expansion of market demand, PTCR material production efficiency gradually increased, the traditional manual sorting have been unable to meet the needs of industrial production. Therefore, the automatic sorting device of the PTCR has been designed in this paper.In general, the sorting machine evaluates the quality of the products by the voltage--withstanding test method. After the detection, it sorts out the unqualified products by the elimination method. The design scheme of the sorting machine is initially formed. It mainly includes the design of mechanism and control system.In this paper, the mechanical structure of the sorting machine has been designed and assembled using the 3D drawing software Solidworks. According to the function, the sorting machine comprises transmission mechanism, feeding mechanism, detection mechanism,sorting mechanism, discharging mechanism and working table. Among them, the work table is divided into up and down two, mainly used to support the various institutions; The transmission mechanism is mainly composed of the cylinder and the motor, which is used for the positioning of the material and the power transmission of the system; The feeding mechanism completes the push of the material; The detection mechanism realizes the detection of the resistance of the sample; Sorting mechanism is for the separation of substandard products; Discharge mechanism achieves the collection of qualified products.Sorting machine control system mainly includes hardware and software. The hardware part mainly includes the drive circuit of stepping motor and the drive circuit of the cylinder.Motor drive circuit using TB6560 driver chip for the realization of the motor speed and steering control. Through the relay, cylinder drive circuit is to control the loss of power electromagnetic valve coil, so as to realize the control on the movement of the cylinder. The software part is for the control of the system by using Keil software. The control program includes the control of motion sequence, the data transmission between the master control unit and the detection unit, and positioning control of separation part.Through the motion simulation, the sorting mechanism can realize the sorting of the unqualified samples. At once, the sorting machine can be detected at 36 stations, and according to the application needs it is able to expand more stations.