(1) LQ-1900K/LQ-1600KIII/LQ-1600K4 print head The LQ-1900K/LQ-1600KIII/LQ-1600K4 print head is a double-layer needle arrangement. The print pins are available in two lengths, one for each length, two for each length, 36 mm for long needles and 26 mm for short needles. The 24 needles of the print head are arranged in odd and even double columns. From the end of the guide plate in front of the print head, the left column is odd and the right column is even. The long needles are: 2, 6, 10, 14, 18, 22, 3, 7, 11, 15, 19, 23; short needles are: 4, 8, 12, 16, 20, 24, 1, 5, 9 13, 17, 17, 21. First use the print head break test program to check which pin has failed, then turn off the printer power, remove the ribbon cartridge, use a Phillips head screwdriver to remove the two printhead fixing screws, and pinch the heat sink from the printheads from both sides. (ie the outer casing), gently lift the print head up to see the two flexible flat cables connected, and pull out the cable to take out the print head. Scrub the ink on the front of the print head with an alcohol cotton ball to see if there is any missing needle. If there is a broken needle, you need to change the needle. Tools should be prepared before changing needles, mainly including tweezers, blades, diamonds, steel rulers, oilstones, and printhead-specific fixtures (a tool specifically designed to remove the printhead heat sink). First use a Phillips head screwdriver to remove the two screws that secure the print sleeve and heat sink. Use a special tool to remove the heat sink. You can see that the print head has several layers of structure, and then change the needle in the following order: 1) With the head of the print head facing down, pick up the triangular claws that fix the upper and lower print pins, and remove the upper rear copper cover to see the 12 long needles distributed in the loop, which are distinguished from the test results. If the broken needle is a long needle or a short needle, then determine the position of the long needle to be broken, and take the broken needle to the side with the forceps; if there is a short needle break, remove the long needle and use the blade along the blade. The yellow copper gasket in the middle is separated underneath, revealing 12 short needles, and the broken needle is taken out in the same way. Then take a good needle from the print head (take the long needle or the short needle depending on the broken needle), then use the steel ruler to accurately measure the length of the needle, and use the new needle to the size of the diamond. After grinding (note the burr of the needle head), insert it from the original position. After replacing the hand, gently press the tails of the 12 needles to make the needles protrude from the guide plate in front of the print head. At this time, the needles of the No. 1 needle and the No. 24 needle should be exposed, and the needles and needles of each column are displayed. There should be a hole between them. If there is a wrong position, it must be re-adjusted. At the same time, each needle can be immediately retracted when the finger is released, ensuring that the needle of each needle is unblocked. Then close the copper seat. Note that the positioning pin of each needle must be dropped into its slot before the copper seat is closed. 2) After confirming that all the short needles are in place, press the upper coil holder (ie, the long needle coil holder) together with the base (copper holder), and apply a set of +10V DC voltage to the drive coils of each group of print pins. (The power-on time should be short, generally less than 1 second, which is equivalent to applying a pulse voltage to the coil) to test the flexibility of each needle and the consistency of the flight distance. So as not to rework after loading the upper print pin (long needle set). 3) Install the upper needle in the original order. Install the long needle layer positioning hole together with the coil holder, and check that there is no gap on the side to install the long needle. Long needles only need to be inserted according to the corresponding hole position. Long needles from the tail to the head, through several guide slots, the top slot is easy to insert. The second slot is slightly more difficult. As long as it passes through, the print pin can go down and easily reach the position. Also press the tail of the 12 needles with your fingers. The needle should be pulled out from the guide plate on the front of the print head by 1mm. It is good to indicate that the needle is replaced. After all the insertions, check that the positioning pins of each long needle must fall into the groove, and then close the rear copper cover. At this time, there should be no gap when viewed from the side. Finally, install the triangular claws, put on the heat sink, and check the long needle group with the +10V power supply according to the test method of the short needle group. After confirming the normal, you can install it on the original printer for testing. Do not install the ribbon before the test, and print a single sheet of paper at the power-on self-test to prevent the new needle from hanging the ribbon. Then use the print head break test program to test, after the normal is determined, it can be put into use. (2) AR-3200/AR-3200II/CR-3240II print head The AR-3200/AR-3200II/CR-3240II three types of dot matrix printers have basically the same print head structure. Except for the elastic force of the three print needle return springs and the resistance of the print needle drive coil, the other is the same. The needles are of a single layer arrangement with a print pin length of 35.2 mm. Check the broken needles in the same way as the EPSON?LQ series printheads described above. Change the needle as follows: 1) With the head of the print head facing down, remove the black plastic case of the print head, remove a movable I-shaped pad, and then open the two metal fixing clips by hand, then remove the rear cover, Print the pin armature spring reed and the white plastic bracket, and you can see the armature of the 24 print pins arranged in a loop. 2) Use the tweezers to take out the broken needle (when the needle is removed with tweezers, the action should be light, do not bring out the nylon pin and the return spring under the print pin), and then remove a good print pin from the print head. Use the rigid ruler to accurately measure the length of the needle, and press the new needle to the size of the needle. After the burr is removed from the needle head by the diamond, insert it from the original position and gently press the armature of the 24 needles with your fingers. The needle is exposed from the front guide plate to see if all 24 pins are coming out. 3) In turn, replace the white plastic bracket, the print pin armature spring reed, the rear cover and the fixed card in the original order, install the print head housing, and apply a set of +10V DC voltage to each group of print pins. On the drive coil (the same method as the LQ series printhead), the flexibility of each print pin and the consistency of the flight distance are tested in turn. 4) Put the print head back on the original printer, first do not install the ribbon, self-test print a single sheet of paper (to prevent the newly installed print needle from hanging up the ribbon), and then use the print head break test program Test, check and normal to use. Soft Sanitary Napkin,Sanitary Napkin Price,Low Cost Sanitary Napkins,Daily Dry Sanitary Napkin Shandong Tianzige International Trade Co., Ltd , https://www.tianzigedipers.com
Print head changing method for several universal needle printers