Design and production of infrared safety protection circuit for forging equipment

This production uses infrared beam detection module, voice recording and playback module and bistable trigger to design and manufacture infrared safety protection device. It uses infrared beams that are invisible to human eyes to form a wireless area detection system. When the operator's body or a part of the body mistakenly enters the dangerous area where the work is in progress and blocks the infrared beam, the infrared safety protection device will immediately operate and send out an alarm signal, and at the same time, the forging equipment will immediately brake and stop, thereby achieving the protection of the machine operator. The whole system adopts a modular structure, with the characteristics of easy installation, stable performance, compact structure, easy light alignment, etc. It is suitable for installation and use on machine tools such as stamping machinery, injection molding machines, and shearing machines.

　　With the rapid development of industrial technology, forging equipment has been widely used in machinery, electrical appliances, vehicles, home appliances, papermaking and other processing industries due to its advantages of strong versatility, high work efficiency and simple operation. Due to the fast beat and frequent loading and unloading of forging production, it is easy to make the operator mentally and physically fatigued. In my country, there are hundreds of thousands of personal injury accidents caused by forging machinery operations every year, with direct economic losses of over 100 million yuan, bringing heavy burdens and disasters to the country, society, enterprises, injured individuals and families. Therefore, it is very urgent and important to design and install infrared safety protection devices on forging machines. In order to ensure the personal safety of machine operators and prevent the occurrence of industrial accidents, this paper uses infrared radiation detection module, voice recording and playback module and bistable trigger to design infrared safety protection device. Once the operator's hands or other parts of the body enter the dangerous area and block the invisible infrared beam, the infrared protection system will immediately act and send out an alarm signal, and at the same time, the machine tool will be braked and stopped immediately.

　　1 Circuit Working Principle

　　The circuit diagram of the infrared safety protection device is shown in the figure below. The circuit mainly consists of an infrared transmitting module and a receiving module, a bistable trigger and a voice recording and playback module. IC1-1~IC3-1 (TX05C-1T) is an infrared transmitting module, and IC1-2~IC3-2 (TX05C-1R) is a matching infrared receiving module. When the operator does not enter the dangerous area, the receiving module receives the infrared signal emitted by the infrared transmitting module and decodes it correctly. Its 0UT output terminal outputs a low-level signal (less than 0.1V), the A, B, and C input terminals of the 8-input NOR gate/OR gate IC4 (CC4078) are low-level, the output terminal of IC4 is low-level, the bistable circuit IC5 (CD4013) has no output, the transistor VTl (9013) is cut off, the relay KS (JZC-23F) is in a released state, its normally closed contact is closed, and the forging equipment works normally. If someone's body enters the danger zone by mistake, it will certainly block the infrared beam. As long as one of IC1-2~IC3-2 (TX05C-1R) does not receive the infrared command, the corresponding infrared receiving module OUT output terminal outputs a high-level signal (greater than 3.5V). After passing through the IC4 circuit, the IC4 (CC4078) terminal output is high-level, and the bistable circuit composed of IC5 (CD4013) is triggered to flip, and its Q1 terminal outputs high-level, transistor VT1 is turned on, and relay KS (JZC-23F) is energized. The normally closed contact is disconnected, causing the machine tool equipment to brake and stop immediately, thus playing a safety protection role. At the same time, transistor VT2 (9013) is also turned on. Its collector flips from high level to low level. The voice recording and playback module IC6 (BA9902) is triggered to work, and the pre-recorded warning statement is played to remind the machine operator to pay attention. BA9902 is a new voice recording and playback module. It can form a high-quality voice recording and playback system with two buttons and a speaker. When recording, use the speaker as a microphone, press the S1 (REC) recording button, the circuit enters the recording state, and the recording indicator (LED) lights up until the memory is full or the REC button is released. There are two ways to play: one is to touch the S2 (PLAY) button to enter the playback state of the voice recording and playback module until the playback ends. The other playback method is to use pulse triggering, which is effective at low level. In the automatic control system, using pulse triggering to play can omit the playback button S2.

　　2. Infrared transmitting and receiving module structure

　　The key component of this production is the infrared transmitting and receiving module TX05C-1, which is the latest infrared transmitting and receiving module developed and produced by Tianjin Texin Electronics Factory. This module can be used to form a beam-type electronic switch. The basic principle is to use infrared beams that are invisible to the human eye to form a wireless area detection system. When a person or object blocks the infrared beam, the receiving module will automatically output a high-level signal, which will drive the relay or other mechanism to operate. Achieve the expected effect. Since the TX05C-1 module contains a dedicated password modulation circuit, it is not interfered by external light or other circuits. It has high reliability and anti-interference ability and can be widely used in electronic counting, automatic control, security and other products. TX05C-1 is divided into two modules: transmitting (TX05C-1T) and receiving (TX05C-1R). It uses digital coding technology. When encountering strong light interference or using a light source for decryption, the detection circuit of the receiving module will issue an alarm, and the circuit will not operate. This design makes the circuit have a strong anti-interference ability. The operating voltage of the transmitter module TX05C-1T is 5~12V, the operating current is 16~70mA, and the effective range is 3~7m. The internal circuit of the receiving module is equipped with a micro-power voltage regulator circuit, which consumes very little power and has an operating voltage of 7-12V. When the signal sent by the transmitter module is received and decoded correctly, its operating current is 1mA. When the decoding is wrong, the working indicator light flashes. The receiving circuit leads out a cable to introduce power and output signals. The red core wire is connected to the positive pole of the power supply, the white core wire is the signal output 0UT end, and the shielding layer (copper mesh) is connected to the negative pole of the power supply. The outer dimensions of the transmitting and receiving modules are 32mm×46mm×17mm, and the working indicator light is installed on the outside. The internal schematic diagram is shown in the figure below.

　　The infrared safety protection device is an infrared safety protection device made by using an infrared beam detection module, a voice recording and playback module and a bistable trigger. It uses infrared beams that are invisible to the human eye to form a wireless area detection system. When the operator's body or a part of the body mistakenly enters the dangerous area where the operator is working and blocks the infrared beam, the infrared safety protection device will immediately act and send out an alarm signal, and at the same time, the forging equipment will immediately brake and stop, thereby achieving the protection of the staff. The entire system adopts a modular structure, with the characteristics of easy installation, stable performance, compact structure, etc. It is suitable for installation and use on machine tools such as stamping machinery, injection molding machines, and shearing machines. Because the device adopts digital coding technology and infrared modulation technology, it can not only resist visible light interference, but also does not affect people's sight, which is conducive to operation. Therefore, it has a good application prospect.