2. Draw the part processing diagram and prepare the processing technology, select the part processing tools, design the process equipment and special measuring tools. Responsible for the material consumption quota, provide the list of materials and outsourcing parts. Familiar with the calculation method of working hours, and determine the preparation time and processing time of the corresponding process according to the process requirements.
3. In-depth practice, timely follow up and guide the service to the production workshop site and the outsourcing parts processing site, solve the process problems, and be responsible for the improvement and perfection of the production process. Be responsible for out-of-tolerance and scrapped products caused by process problems.
4. Be responsible for supervising and inspecting the implementation of technical standards. Assist the production department to organize production workers to learn job responsibilities and other relevant standard documents, and require production workers to carry out production in strict accordance with technological procedures and post safety operation procedures. If violations are found, they can be corrected or even suspended.
5. Actively participate in quality management and technological innovation activities. Assist the quality control department to hold regular quality analysis meetings and strive to improve product quality. In case of quality accident, cooperate with the quality control department and production workers to conduct quality analysis, find out the causes of nonconforming products, put forward improvement measures and suggestions, and learn lessons seriously to prevent similar problems from happening again. Organize technical research and solve technical problems.
6. Responsible for the collection and filing of production records of each process. Responsible for the management of production files and production equipment data files. All files and materials shall not be lent out in principle, and special circumstances shall be examined and approved by the competent factory director. All borrowed materials shall not be altered, torn, defaced or lost.
7. Responsible for the installation, debugging, review and acceptance of new production equipment. Participate in equipment repair, inspection and appraisal, relocation and deployment, scrap purchase, equipment accident handling, etc. , and solve technical problems. Arrange secondary and tertiary maintenance plans and maintenance plans for production equipment.
8, responsible for writing new production equipment operation procedures. Responsible for the guidance and technical training of workers' production operation, and responsible for the skill level examination of workers.
Process report
I. Purpose and benefits
Familiar with the use, maintenance and repair of common tools for manual welding. Basically master the welding technology of manual electric soldering iron, and can independently complete the installation and welding of simple electronic products. Familiar with the production process of electronic product installation technology, the steps and methods of printed circuit board design, the process of hand-made printed circuit board, according to the circuit schematic diagram, physical components. Understand the category, model, specification, performance and application scope of common electronic devices, and be able to consult relevant electronic device books. Be able to correctly identify and select common electronic devices, and skillfully use ordinary multimeter and digital multimeter. Understand the welding, debugging and maintenance methods of electronic products. Through the monitoring and debugging of the radio, we can understand the production and debugging process of general electronic products, learn the methods of debugging electronic products initially, and cultivate the detection potential and meticulous scientific style.
Second, principles.
An antenna receives an electromagnetic wave signal and selects a radio signal to be received after frequency selection by a tuner. At the same time, in the radio, there is a local oscillator, which produces a local oscillator signal similar to the receiving frequency, and it is mixed with the receiving signal to produce a difference frequency, which is the intermediate frequency signal. The intermediate frequency signal is detected after intermediate frequency selective amplification to obtain the original audio signal. After power amplification, the audio signal can be sent to the speaker to make sound. The high-frequency signal received by the antenna and the local oscillation frequency of the radio (its frequency is higher than the external high-frequency signal by a fixed intermediate frequency, and the intermediate frequency standard in China stipulates that it is 465KHZ) are sent to the frequency converter, and a new frequency is generated in the load loop (frequency selection) of the frequency conversion stage, that is, the intermediate frequency generated by the difference frequency. If only changes the carrier frequency, and the original audio envelope remains unchanged. The intermediate frequency signal can be amplified better, and the intermediate frequency signal is detected and filtered. After low amplifier and power amplifier, the speaker is driven to sound.
Third, the installation and debugging
1。 examination
(1) Preparation before power-on.
(2) Self-inspection and mutual inspection make the quality of welding and printed board meet the requirements, and pay special attention to whether the resistance values of each resistor are consistent with the drawings, whether triode and diode have polarity welding errors, wrong installation positions, broken or short circuit of copper foil wire of circuit board, and whether there is short circuit caused by solder during welding.
(3) Before connecting the power supply, be sure to check whether the power supply has an output voltage (3V) and whether the positive and negative poles of the lead-out wires are accurate.
Preliminary test.
(4) Turn on the power supply (pay attention to+and-polarity), dial the frequency dial to the radio-free area of 530KHZ, and measure the total static working current of the whole machine when the radio switch is not turned on. Then turn on the switch of the radio, measure the voltage values of the three electrodes of transistor T 1 ~ T6 to the ground (that is, the static working point), and fill in the measurement results in the internship report. When measuring, pay attention to prevent the point to be measured of the stylus from being short-circuited with its adjacent points.
Step 2 troubleshoot
After power-on inspection and normal sound, debugging can be carried out.
(1) intermediate frequency modulation (commonly known as mid-cycle modulation)
Objective: To adjust the mid-cycle resonance frequency to a fixed intermediate frequency of "465KHZ".
(2) adjust the frequency range (usually called frequency coverage or calibration)
(3) Unified adjustment (agility adjustment and tracking adjustment)
Objective: Through a fixed intermediate frequency of "465KHZ", the local oscillator frequency is always higher than the resonant frequency of the input loop.
Methods: Low-end: the signal generator was adjusted to 600KHZ, and the low-end radio was adjusted to 600KHZ. Adjust the position of T 1 coil on the magnetic bar to send out the signal (generally, the coil position should be close to the right end of the magnetic bar).
High-end: the signal generator is adjusted to 1500KHZ, the high-end radio station is adjusted to 1500KHZ, and the high-end signal is adjusted to C 1a'.
The high and low ends are repeatedly adjusted for 2 ~ 3 times, and then the coil is fixed on the magnetic bar with wax.
Fourth, summary.
Problem analysis: When welding the radio, the most important thing to pay attention to is the welding temperature and time. When welding, the temperature of soldering iron should be higher than that of solder, but not too high. The rosin in the soldering iron joint just smokes, and the welding time should not be too short. Because of this, the solder joint temperature is too low, the solder joint is not completely melted, and the solder joint is rough, which is easy to cause virtual welding. However, after a long welding time, the solder is easy to flow, which makes the components overheat, easy to be damaged and easy to burn out the printed circuit board.
Welding sequence:
First, weld the middle perimeter. In order to keep the balance of the printed circuit board, we need to weld the middle perimeter of two diagonal corners first, and then before welding, we must identify the color of the middle perimeter to avoid welding errors. Never weld all three middle peripheries of the top at once, which will make it difficult to install small parts in the future.
Second, welding resistance, measure the resistance of the resistance and then don't put it on paper. We should weld in the order of R 1-R8 to avoid leakage of resistance. After welding the resistance, we need to use a multimeter to check whether the resistance is the same as the previous value (check whether there is virtual welding).
Third, welding capacitors, first welding ceramic capacitors, pay attention to the above readings, and then welding electrolytic capacitors, pay attention to the personality that long legs are "+"poles and short legs are "-"poles.
Four, welding diode, red end is "+",black end is "-".
Five, welding triode,-be sure to recognize the "E", "B" and "C" pins.
Six, the rest of the middle weeks and transformers and switches can be welded.
Seven, the most need to be careful is to weld the antenna coil, and the four wires must be welded accurately according to the circuit diagram.
To weld the discontinuous part of the ""shape on the printed circuit board, we need to connect other doors with solder.
Nine, welding horn and battery holder.
Testing and testing: testing is a very difficult and patient task, but its purpose and benefits are extremely important. Through radio testing and testing, we should understand the production testing process of general electronic products, initially learn the methods of testing electronic products, and cultivate the testing potential and meticulous scientific style. First of all, check whether the printed circuit board is damaged at the welding place and whether the resistance is the same as the drawing. Whether all diodes and triodes have polarity welding errors, misplaced positions, broken or short-circuited circuit boards, short-circuited phenomenon caused by welding, and whether the positive and negative poles of power lead-out wires are correct. Second, it is necessary to conduct power-on test-carefully adjust the mid-cycle when power-on, and be sure to record every adjustment process. If the adjustment fails, reset the belt to its original position and ask the teacher for help! But in the whole process, we must be patient.
Production experience: After two weeks of electrical and electronic practice, I learned the basic welding technology, radio detection and testing, assembly technology of electronic products, identification and quality inspection of electronic components and assembly technology of the whole machine. All these have cultivated our practical potential and rigorous work style and laid a good foundation for our future work. The most basic point: study before.