6.3 Maintenance of paper path
The role of the paper path is to accurately and stably transfer the paper from the paper feed section to the delivery section. Therefore, the workability of the paper path directly affects the paper conveying accuracy. There are many factors that affect the accuracy of paper transport. The following is a detailed analysis of these factors based on the paper drive chain diagram.
The paper drive chain diagram is as follows:
Paper Feeder - Feida - Paper Paper Tongue - Conveyer Roller and Platen Wheel - Double Sheet Controller - Paper Feeding Tape, Paper Feeding and Paper Roller - Pressing Frame - Front and Side Guards (Paper Failure Detector ) - Swinger - Front Transfer Roller I - Impression Roller I - Rear Transfer Roller I - Double Pass Transfer Roller - Front Transfer Roller II - Imprint Roller II - Delivery Roller - Flat Roller - Anti-Dirty Device - Powder spraying device - brake roller - fan - open plate - front trim mechanism and side trim mechanism - delivery table.
Paper table
The paper table is one of the important factors for keeping the surface of the paper conveying pile flat. Considered from an ideal state, no backing should be inserted in the middle of the paper stack placed on the paper feed table, and its surface should be in a horizontal state, which requires the paper feed table to be absolutely horizontal. However, in reality, due to the uneven distribution of air in the middle of the paper, as well as the non-uniform thickness of the paper itself, the unevenness of the ink layer on the surface of the printing product during the reverse printing or the chromatic printing, eventually making the surface of the paper stack uneven (even if The paper binding table is absolutely horizontal). However, it is not because of this that the level of the paper feed table is not noticed because the paper feed level is the reference for the level of the paper feed surface. The paper table is not horizontal, and the paper level is not stable (the pile is easy to slide in a certain direction). Therefore, as far as possible, the paper feed table should be in an ideal horizontal state.
The lifting and lowering of the paper-feeding platform is achieved by the motor driving the chain. Due to the frequent relative movement between the chain and the sprocket, wear occurs over time. Therefore, regular lubrication should be added. But because the chain is exposed, dust and paper dust easily fall on it. If you add oil to the chain. The oil and dust and paper powder are easily mixed together to form sludge, which in turn accelerates chain wear, so chains should be scrubbed frequently. If you don't add oil, the chain will rust for a long time, and it will produce noise when you move.
The load-bearing capacity of the paper-feeding platform is based on the maximum paper pile design. Of course, there will be a certain safety factor, but it cannot be put on anything. If you put some heavy things on it, the chain will be stretched, and it will not be able to properly cooperate with the sprocket, resulting in unstable lifting. The paper stack on the paper table should not be piled up too high, and the paper feed energy should be raised to the lower limit switch position. Nothing should be put under the paper table (such as stools, chairs, etc.), otherwise the paper table is lifted up, causing the paper table to tilt, and other accidents may result. In addition, if you continue to feed the paper table down button, there will be hard interference between the chain and the sprocket and the motor. As a result, some of the components are damaged. It is also important to note that when pulling paper or pushing paper with a technical paper cart, do not allow the paper stack to collide with the pillars of the paper feed table. Otherwise, the pillars will be bent. In severe cases, the pillars will be broken, which must not be careless.
2. Feida
The work of feeders directly affects the accuracy of paper delivery. The movement of Feida's components (separator nozzle, presser foot, delivery nozzle, etc.) is determined by design, but due to long-time operation, it will cause a certain degree of wear, but this amount of wear is very small, because The relative motion of the contact surfaces are made of wear-resistant materials. In addition, even if some errors are caused by wear, this error can be compensated by adjustments made by other mechanisms, so the accuracy of the transfer accuracy of Feida is not very strict. Feida's relative movement mechanism is covered with a hood to prevent dust and other impurities from entering the relative movement contact surface. In fact, it is difficult to completely cover it. Adding oil to these relative kinematic contact surfaces may create sludge on the surface and accelerate wear, so these areas should be regularly scrubbed.
Paper feeder nozzles and paper feeder nozzles on feeders frequently move up and down. Self-lubricating materials are used for relative movement contact surfaces. Because the paper surface is closest to the surface and is under negative pressure, debris such as paper dust easily falls onto it. If you add oil to it, it will form a sludge that will accelerate wear on these parts. Once it wears, it will cause a leak, causing the suction nozzle to inhale insufficiently. So refueling is prohibited here. If it is found to be insufficiently inhaled, some remedial measures may be taken and, if the measures are still ineffective, they will need to be replaced.
Feida not only can adjust its front and rear position, but also the left and right position can be adjusted, but the left and right position can not be arbitrarily adjusted. Theoretically speaking, the dual gimbal driveshaft that drives Feida motion must be absolutely parallel. However, due to the carelessness of the installation, it may cause inaccuracies in its left and right positions. At this time, it must be carefully checked and debugged.
3. Paper tongue
The role of the paper stop tongue is to make the front edge of the paper flush, but due to the impact of the forward movement of the paper, the position of the individual tongues will change. When its position changes, it can no longer play the role of paper flush, and it is easy to cause the paper to arrive early. Therefore, if you find that the position of a paper sheet has changed, correct it in time. It should be noted that the correct timing between the stopper and the transfer nozzle. Due to the relatively thin shaft of the paper tongue, in order to improve its impact strength, three-point support is generally used. But we must pay attention to three points in a straight line, so as to ensure its smooth operation. When it swings toward the forward direction of the paper feed, it is completely driven by the spring, and the rigidity of the spring is extremely small. As long as there is slight resistance, it cannot swing back and forth.
4. Take-up roller
The role of the take-up roller and the platen roller is to forward the paper conveyed by the delivery nozzle to the delivery plate. The upper surface of the take-up roller is rough, which is mainly used to increase the friction, because it will drive the movement of the paper feeding belt through it. The current take-up roller part of the machine adopts horizontal stripes to increase the friction. This kind of friction is beneficial and therefore cannot be lubricated with oil. The speed match between the take-up roller and the transfer paper catcher is given by design and should be taken into account when changing the take-up roller. The pressure roller on the take-up roller is mainly used to increase the frictional pressure, but the pressure should not be too large. For older machines, the left and right position of the platen can be changed. The rotation of the pressure roller is driven by friction. If the pressure roller is not flexible, it will cause the paper to slide. Always turn by hand and observe its operation.