Design scheme of intelligent seal machine based on STC89C52

This paper proposes a design scheme of the automatic seal machine with STC89C52 single-chip microcomputer as the control core. The program realizes the automatic operation, intelligent stamping, adjustment and storage data function of the seal machine by writing the relevant program and various user parameters.

The design part of the intelligent seal machine control circuit mainly includes display circuit module, data storage, motor drive, sensor and manual adjustment module. The functions of each circuit module are realized through independent research and development program. In actual application, the delay time and quantity of stamping chapter can be timely Monitoring and adjustment to improve stamping quality and speed, and the use of a variety of photoelectric sensors to control motor motion stroke to achieve precise positioning control in order to achieve different document stamping requirements, practical.

0 Preface

In banks, governments, schools and other institutions, there are a large number of documents that need to be stamped. When the number of stamped documents is too large, it takes a lot of manpower and time. The smart seal machine designed in this paper can significantly shorten the seal time and save a lot of manpower. Everyday office needs. And with manual setting function, the delay time of stamping can be set manually, and the number of stamps. The main components of the intelligent seal machine control circuit designed by this paper are: power supply circuit, motor drive circuit, sensor circuit, data storage circuit, The data display circuit and the manual control circuit are composed.

1 system overall block diagram

The working principle of the intelligent seal machine stamping is to detect whether there is paper signal by the photoelectric sensor installed at the bottom of the machine to open the control of the motor by the single-chip microcomputer, and drive the seal movement to complete the stamping action through a series of transmission structures. The number of stamps and stamping delay can be adjusted through the manual control panel before stamping. At the same time, when the seal machine is working, the number of sheets covered by the stamp machine will be recorded by the data storage circuit, and the manually set number and stamp delay data will be stored. The overall system block diagram is shown in Figure 1.

2 hardware design

2.1 voltage regulator circuit design

In the control circuit part, the control circuit and the sensor circuit composed of the single chip microcomputer are simultaneously supplied with power. The LM7805 three-terminal integrated voltage regulator and filter capacitor are selected to form a power supply circuit to provide a stable voltage for the entire control system, as shown in Figure 2.

2.2 Motor drive circuit

The motor uses a 24 V DC motor. The driver chip L298N is a high-voltage and high-current motor driver chip produced by ST. The main features are high operating voltage, large output current, instantaneous peak value of 3 A, and standard logic level signals. Control, INPUT1 and INPUT2 are the two inputs of the MCU control motor. OUTPUT1 and OUTPUT2 are the two outputs, which are connected to the positive and negative electrodes respectively. Since the motor used is coil type, it suddenly switches from the running state to the stop state and A sudden transition from a clockwise state to a counterclockwise state creates a large reverse current, so a diode is added to the circuit to provide shunt protection when reverse current is generated. The drive circuit is shown in Figure 3.