1.3 Rules The role of the regulation part positions the paper so that each piece of paper can enter the printing unit at the same position, so its accuracy directly determines the size of the printing error, so the installation and adjustment of the regulation part is very important. . 1. The working principle of the rules section. How is the paper positioned in the regulation part? In actual work, the paper first arrives at the front gauge. After the front gauge is at rest, it is pulled toward the side gauge. The front gauge positions the paper in the forward direction, and the side gauge positions the paper laterally. The front gauge of general machines is at least two, most of them are more than four, but only two are used for positioning. Why only use two? This is because two points define a straight line, if there is less, it will interfere with each other if there is more. After the pre-positioning of the side rule is completed, the paper is pulled toward the ruled edge. This actually adds another anchor point on the paper. In addition to the two points of the previous rule, a total of three points are used to position the paper, so the entire plane position of the paper is determined. It can be seen from the foregoing analysis that the positioning principle of the regulation part actually uses the geometric principle of two points, one line and three points and one side. A simple analysis of paper positioning is made above, and a more in-depth analysis shows that the paper is not only plane-oriented, but also spatially-oriented, that is to say, the entire paper is always placed in a certain space. The spatial positioning of the paper has high requirements on the working state of the regulatory part, which is one of the keys to adjust the front and side regulations. 2. The role of the previous regulations. The front rule positions the paper longitudinally, which is one of the main functions of the front rule. In addition, the pre-regulation has many other functions. The following summarizes and summarizes these functions. (1) Longitudinal positioning of paper The longitudinal positioning of paper directly determines the accuracy of overprinting in this direction. If the paper is not positioned in this direction or the positioning is not correct, it will cause a series of printing failures. Such as pleating, ghosting, etc. 3. The classification and working principle of the previous regulations. (1) Classification of pre-regulations Pre-regulations are generally divided into two types: up swing and down strike. The upper swing-type front gauge is compared with the lower swing-type front gauge: one is that it is very convenient to adjust and install; the second is that the paper with a ruffled edge on the front mouth can be eliminated without adding any other mechanism; Compared with the top swing-type front gauge, the gauge can return to the paper feeding board before the paper has completely left the paper feeding board, which increases the positioning time of the front board and makes it easier to ensure the positioning accuracy. When the positioning time is constant, the speed of the machine can be increased. Therefore, the front swing-type front gauge is suitable for low-speed large-format or high-speed small-format, while the bottom swing-type front gauge is suitable for high-speed large-format, which is also an obvious feature of contemporary offset presses. The disadvantage of the swing-down front gauge is the complicated installation and the need to add a mechanism to eliminate the frill edges. (2) The working principle of the front gauge The pendulum front gauge does not need a mechanism to eliminate the ruffles, it only swings. Under normal circumstances, its swinging action is achieved by the cam driving link mechanism. There are the following requirements for pre-regulatory sports: ①When positioning the paper, it should be stabilized on the cardboard beforehand. The height regulation of the front regulation must consider the change of the paper and its influence on the side regulation. This point will be analyzed in detail when it comes to side regulations. 4. The role of side regulation. Positioning the paper laterally is one of the main functions of the side rule. Like the front rule, the side rule has many other functions. Let's analyze each function in detail. (1) The lateral positioning of the paper The lateral positioning of the paper is an important measure to ensure the accuracy of the overprint of the paper laterally. The pre-positioning is accurate. If the side position is not correct, it will cause great difficulties for the subsequent overprinting or cutting of the printed sheet. (2) Make up for the errors of plate-making and plate-making. When the current regulation is adjusted according to the errors of plate-making and plate-making, the angle of the side gauge baffle plate also needs to be adjusted in theory. Positioning. Therefore, this institution is also set up on the side regulation. (3) The lateral pull amount of the side gauge to compensate for the error of paper feeding or paper cutting is 0-12mm, how much is the best choice among them? If you choose 12mm, it is the maximum pull amount. Choose this amount of pull paper as long as the paper can be positioned within the reach of the pull gauge. However, due to paper feeding and cutting errors, some papers may be 12mm away, and such papers cannot be positioned. If 0mm is selected, the paper is not pulled, which is obviously the same as without side gauge. The paper becomes two-point positioning, which does not meet the requirements of plane positioning. Generally, the amount of paper drawn is 5-8mm. Selecting 5-8mm paper pulling amount does not mean that each time the paper pulling amount is 5-8mm. The amount of paper drawn is only an average, and most of the paper is within this range of paper receiving. If some paper is out of this range due to paper feed errors. More than 8mm, more pull, less than 5mm, less pull. Therefore, the amount of paper pulled actually varies between 0-12mm. (4) Various papers and formats can be adjusted. During printing, due to changes in paper format and thickness, the lateral rules can be adjusted accordingly to ensure accurate lateral positioning. [next] 5. Types and working principles of side gauges. (1) Classification of side regulations Side immortals are generally divided into two types, namely push regulations and pull regulations. The push gauge pushes the paper to position laterally on the opposite side, and the pull gauge pulls the paper to position laterally on the ruled edge. Push gauges can still be seen on older machines. Now most of the presses use pull gauges. This is because of the flexibility of the paper, it is difficult to maintain the positioning accuracy with a push gauge. The next thing to talk about is the side pull gauge. Side pull gauges are fan-shaped plate type, roller type, magnetic strip type and so on. Fan-shaped plate-type pull gauges have been used on earlier domestic machines, and are now basically eliminated. At present, almost all Beiren equipment uses roller type. Heidelberg equipment uses magnetic stripe pull gauges. The advantage of the roller-type pull gauge is to change the reciprocating motion into a rotary motion, so the inertial impact is small. The disadvantage is that the contact surface with the paper is small. When the vibration is large, it is easy to cause overprinting. The characteristic of the magnetic strip pull gauge is that it can obtain a larger contact area with the paper, and it has little effect on the positioning accuracy of the front gauge, but this structure is relatively complicated and the installation accuracy requirements are also very high. There are the following requirements for the movement of the side gauge: ①The paper can only be pulled after the previous regulations are completed; ②The side rule must be away from the surface of the paper when the paper picks up the paper; ③It must be stable during the paper pulling process (the side rule and the paper are always in contact). (2) Analysis of the principle of the side gauge pull paper The side Xian pull paper relies on friction force, and the formation principle of friction force is basically similar to that of the friction force of paper on the paperboard. Therefore, to reliably position the paper, friction must be created. Force formation conditions. The paper stress analysis is as follows: f1 is the frictional force generated by the driving part, f2 is the frictional force generated by the driven part (generally refers to the rollers), and f3 is the frictional force generated by other parts on the surface of the paper. According to the motion requirements, f1 = f2 + f3. Both f1 and f2 are proportional to the pressure of the side gauge spring. f3 is proportional to the force of other components on the paper. The f3 force includes: the friction between the paper and the paper, the resistance of the side pressure plate, etc. The relationship between the three forces f1, f2 and f3 directly affects the positioning accuracy. According to the role of the side gauge, it can be seen that the side gauge should have the following functions: ①According to the change of paper size, the horizontal direction can move relatively; 6. The effect of the previous regulations on the lateral regulations. First of all, the front regulation is the benchmark for the side regulation. Only when the front regulation is accurate, the side regulation is meaningful. Secondly, if the front gauge is too low, it will cause greater friction on the surface of the paper, thereby destroying the condition of the side gauge friction transmission; if the front gauge is too high, the positioning accuracy is very low, and the side regulation position cannot be The paper is effectively corrected. Therefore, the front gauge should not be too high or too low. Generally, the height of the front gauge is the paper thickness plus 0.20mm, which can basically maintain the positioning accuracy, and at the same time, the friction that hinders the lateral movement of the paper is relatively small. If the side gauge is to be positioned accurately, all friction must be overcome. This must be avoided when adjusting the machine. The height of the side gauge baffle is the paper thickness plus 0.20mm, which can ensure that the resistance of the paper into the side gauge is relatively small. Another is to adjust the pressure of the puller, thereby changing the conditions of friction transmission. Therefore, it is necessary to pay attention to the influence of the front regulation on the side positioning, and the front regulation with the push-down type should pay more attention to this point. 7. Pass the paper tooth. Paper delivery is an extremely important part of making paper from a semi-free state to a controlled state. The reliability of this state directly affects the accuracy of overprinting, so no matter from design, processing, or installation, all parties face high requirements for paper transfer teeth. In general, the following requirements are required for paper delivery: (1) Self-trajectory ①Compared with the paperboard, take the paper absolutely still. This is a key step in paper handover. Only when it is absolutely stationary can the stability of the handover be guaranteed and the positioning accuracy of the paper will not be damaged. (2) Requirements for relative motion ①After the front and side regulations are set, the paper feeder can only pick up the paper on the transport board. (3) Requirements for movement trajectory ①The trajectory is smooth and the inertial impact is minimum. (4) Requirements for its own accuracy ①All dental pads are flush and the friction coefficient is evenly distributed. 8. Various types of paper delivery teeth and their working principles. Paper delivery teeth are generally divided into four categories: up-swing, down-swing, roller, and beyond. (1) Up-swing type Up-swing type is divided into four categories: centering up-swing type, eccentric swing type, eccentric rotary swing type. ①Centering and swinging type: The transfer path of this paper delivery tooth is inconsistent, that is, when the rollers return to the paperboard, the position of the paper delivery tooth is relatively high, and the height varies with the eccentricity, but this paper delivery tooth structure It is complicated and the inertial impact increases with the increase of the eccentricity, so the eccentricity cannot be particularly large. Sometimes it is necessary to add a special anti-scratch mechanism ② eccentric rotary swing type: this paper delivery tooth is similar to the eccentric swing type above, and the inertial impact is relatively small. (2) Analysis of the rubbing principle of the swing-up mechanism. When the paper passing tooth passes the paper to the subsequent roller, the paper will be oriented along the tangent direction of the roller, as shown in Figure 1.14. In this way, the paper feeding teeth can easily rub against the tail of the paper when swinging on the return stroke, especially thick paper or high speed, which is more serious. Therefore, when printing thick paper or high speed, there must be a special anti-smudge mechanism. The anti-smudge mechanism mainly bends the tail of the paper, which prevents the paper feeding teeth from rubbing against the paper. (3) Bottom swing type There is only one type of bottom swing type seen at present, namely the centering swing type. If there is no eccentric swing type, the main reason is probably that the installation space is too small. Compared with the pendulum type, the most important advantage is that the paper feeder can return to the paperboard before the paper has completely left the paperboard, which can extend the handover time and improve the stability of the handover. Increase the speed of the machine. (4) Analysis of the rubbing principle of the swing mechanism. When the paper feeder passes the paper to the subsequent roller, the paper will be oriented along the tangential direction of the roller. As shown in figure 3.14. In this way, the paper feeding teeth can easily rub against the surface of the paper when swinging back, and the tail of the paper starts to vibrate at the moment when the paper leaves the paper feeding board. The amplitude of the previous one or two weeks is particularly large, so the possibility of smudging is also very high. For high-speed or thick paper printing, this phenomenon is more prominent. Therefore, a special anti-rubbing mechanism must be added. The currently used method is to add a freely rotating roller to the tooth pad, so that when the tail of the paper collides with it, there is no relative sliding between it and the paper, thereby avoiding rubbing. Even so, if the paper is particularly thick and the speed of the machine is high, the impact of the tail of the paper is very large, and it is still easy to damage the graphics on the back of the printed sheet. (5) Rotary drum type Rotary drum type is generally divided into two types: one is intermittent type, the other is uniform speed rotary type. The former is mainly used on low-speed machines, and it is now tending to be eliminated. Heidelberg presses are currently the most commonly used constant speed rotary type. One of the biggest advantages of the uniform rotation type is that the possibility of smudging is completely eliminated, and the impact is less than the eccentric swing type. However, this paper-feeding tooth can only return to the paper-feeding board after the paper completely leaves the paper-feeding board. Compared with the hem type, there is a problem of insufficient paper-taking time. Another disadvantage is the structure of this paper-feeding tooth. complex. Therefore, in high-speed printers, this kind of paper transfer teeth is likely to be eliminated. (6) The positioning of the surpassing surpassing continuous paper is carried out on the drum, so the speed of the machine can be higher, but due to the accuracy of the positioning of this mechanism, especially for large format, the positioning accuracy is lower, so it is generally This mechanism is used on small offset presses. The transcendental type is generally divided into two types, namely pneumatic type and friction type. The pneumatic type transfers the paper to the roller by the pressure difference, and the friction type transfers the paper to the roller by the friction wheel. [next] 9. Interlocking mechanism. (1) The function of the interlocking mechanism is to fix the position of the paper on the cardboard when the machine fails. The swinger does not pass paper. The purpose of the interlock mechanism is fourfold: ①Protection of printed products: After the interlocking mechanism is activated, the printed sheets are fixed on the paperboard. After the fault is eliminated, the paper can still be used. Otherwise, if the paper is skewed and the paper feed continues to pass, the left and right bites will be different, the accuracy of the overprint will be destroyed, and there may be a series of printing failures such as ghosting and wrinkling. (2) The action of the interlocking mechanism is divided into two parts ①Stop the paper on the paperboard: There are many ways to stop the paper on the paperboard. Heidelberg presses use suction under the cardboard and press paper on the cardboard. The domestic equipment adopts the suction under the cardboard, and the former regulations stop on the cardboard. The former regulations stop on the paperboard or press the paper on the paperboard are controlled by a special mechanism. The important role of the interlock mechanism determines that it must always be in a normal working state. 10. Analysis of the movement process of paper in the paper conveying part. The paper is transferred by the paper suction nozzle to the paper roller from the stationary state at the paper stack. After the paper pick-up roller conveys it to the regulation part, it is at rest again. The paper underwent a process of acceleration, deceleration and re-acceleration during this period. The paper acceleration process is obvious, but how is the paper deceleration process achieved? (1) The frictional force that drives the paper forward is no longer present when the paper is conveyed to the paperboard at a constant speed transmission, but when the front opening of the paper leaves the conveyor belt, the frictional force of the drive gradually decreases. After a paper feed step has passed, the paper has completely left the paper feed belt. The paper moves forward only by its inertia. Due to the existence of frictional resistance, its inertia gradually decreases, thereby reducing the speed of the paper. (2) The angle of the front gauge plate is different from the angle of the paperboard. The angle of the front gauge plate is smaller than the angle of the paperboard. In this way, the direction of the paper uploaded from the paperboard changes, which changes its speed. It can be known from the speed analysis that the speed decreases. (3) After the front gauge slows down, the paper arrives at the front gauge, and some of the paper arrives closer, and some goes farther, but if the paper reaches zero speed before the paper arrives, then the front gauge cannot compensate for the paper error. To the role of positioning. Therefore, when the paper reaches the front gauge, the speed should be slightly greater than zero. In order to prevent the paper from rebounding, a brush wheel is added at the tail of the paper to absorb the rebound level. The subsequent paper also has a certain hindrance to the paper's rebound. 11. Adjustment of paper feeding part. (1) Benchmark. The starting point of all actions and behaviors. There is only one starting point, and this starting point is called the absolute reference. For a machine, the machine's benchmarks include design benchmarks, machining benchmarks, installation and commissioning benchmarks. Relative benchmark: This action and behavior take the absolute benchmark as the starting point, but it is also the starting point of some other actions and behaviors. This starting point is called the relative benchmark. The relative benchmarks are generally more than one, but their status is not equal. Without a benchmark, there is no starting point for actions and behaviors, then all actions and behaviors must be a mess. Therefore, when designing, processing, installing and commissioning the machine, the benchmark and relative benchmark must be found, otherwise the machine cannot be manufactured. (2) Tuning benchmark. The starting point of the time and displacement of all parts of the machine, there is only one reference, called the absolute reference for tuning. In addition to the absolute reference, there is a relative reference for tuning. It means that the time and displacement of a certain part are based on the absolute reference of the tuning, but some other parts use this time and displacement as the starting point. It is called the relative benchmark of tuning. There is generally more than one relative benchmark for tuning. The absolute reference and the relative reference are the basis of machine adjustment. If the reference and relative reference cannot be found, the adjustment cannot be performed. Having mastered the absolute reference and the relative reference, debugging reduces blindness, which is also one of the so-called shortcuts for tuning. (3) The absolute reference for the adjustment of the printing machine and the relative reference for the adjustment of the machine are different for different models, but there is only one absolute reference for the adjustment of the machine. The absolute benchmark for some machine debugging is the impression cylinder, and some are the registration cylinder. At present, the absolute reference of the general multi-color printing machine adjustment machine is the registration cylinder (the paper transfer tooth is regarded as a part of the registration cylinder). It doesn't matter which one is selected as the absolute benchmark for tuning, but once selected, it cannot be changed halfway, otherwise all work needs to be started from the beginning. In other words, the absolute reference is not adjustable. The relative reference depends on the drive chain. (4) The time and displacement of each part of the transmission chain are connected in a certain order. This chain is called the transmission chain. The unadjustable point on the transmission chain is the absolute reference of the machine. All points except the absolute reference point and the last point of each branch (except the main chain and sometimes many branch chains) on the transmission chain. Both can be called relative benchmarks. Therefore, when debugging the machine, first analyze its transmission chain clearly, and then find the color-pair reference and relative reference of the adjustment machine on the transmission chain. In addition, there must be a diagram of the relationship between the time and displacement of each component relative to the absolute reference and the relative reference, so that when adjusting the machine, it can be ruled. This is the most basic method of tuning, and it can also be called the tuning principle. (5) Transmission chain of the paper conveying section The transmission chain of the paper conveying section is as follows: Register roller—Regulation part—Paperboard—Feida—Paper stack In this transmission chain, the registration roller is the absolute reference for the adjustment machine. Except for the stack of paper, the other can be called the relative reference of the adjustment machine, but the status of these relative benchmarks is different. , Followed by other, according to the distance between the absolute reference, can be divided into first, second, ... relative reference. Here the rules are the first relative reference, the paperboard is the second relative reference, and the Feida is the third relative reference. After finding the absolute reference and relative reference of the paper conveying part, and then preparing the relationship diagram of the time and displacement of each part with the reference and relative reference, the paper conveying part can be adjusted. The specific practices are briefly described as follows: ①The registration roller is the reference, once its position is determined, it cannot be adjusted relative to any other parts. The cooperation relationship between the registration roller and the rule is this: when the registration roller picks up the paper on the paper feed, the rule part has been positioned, after the hand and the rule part are handed over for a period of time, the front rule hem, the hand Hold the paper away from the paper feeder board, then return to the paper feeder board to locate the subsequent paper, and then move the paper feed back to start holding the second paper. ③Adjustment of the paperboard relative to the regulation part: when the current regulation just reaches the paperboard, the front opening of the paper passed by the paperboard should be about 5mm away from the front regulation. Why keep 5mm? The main consideration is the stabilization time of the front gauge, because the swing of the front gauge is driven by the cam. The front gauge stops on the cardboard, precisely the highest point of the cam is in contact with the swing lever mechanism. This is a filtering point of the cam. Due to the inertia of the front gauge, the front gauge cannot be in an absolutely static state at this point, so the front gauge requires a stable time. Someone once thought that 5mm is used for paper deceleration, this understanding is incorrect. Because the distance from the paperboard to the front gauge is always a fixed value, and the paperboard is always running at a constant speed, the speed of the paper is the same every time it is transferred to the front gauge board. Assuming that the speed of the machine is unchanged, the way to slow down is to increase the displacement, but in fact the travel of the paper on the front gauge plate has not increased due to the 5mm, so how can it play the role of slowing down? From another perspective, If the 5mm distance plays the role of deceleration, then after the speed of the machine changes, the 5mm distance should also change accordingly. The speed is higher and the distance is larger; the speed is lower and the distance is smaller. This assumption actually does not exist at all. How to ensure the distance of 5mm? The only way is to adjust the coordination between the cardboard and the front gauge. The place of this adjustment is generally on the transmission surface of the paper machine, and the mutual relationship between them is changed by the change of the position of the gear or chain, so as to meet the predetermined requirements. ④ Adjustment of Feida relative to the paperboard: During normal operation, Feida should pass the paper through the paper receiving roller about 5mm, then the pressure roller can be pressed down. If it is found that this fit is not correct, Feida should be adjusted. At present, the feeder of the film machine is generally driven by a universal coupling, by changing the position of the long hole on the flange of the end of the universal joint. ⑤Adjustment of the paper stack relative to Feida: When the paper stack is not suitable for Feida, the paper stack should be adjusted first, that is, the paper stack should be in a free state. The above briefly describes the adjustments between the paper-feeding parts. Specifically, the inside of each component can also be adjusted according to this relationship, but one thing needs to be noted that it must not be reversed, that is, the benchmark cannot be reversed. The relatively complex components are the feeder and the rules. The rules section has been described before. The following uses Feida as an example to analyze the adjustment method inside the component. The relative motion relationship of the components in Feida has been fixed at the time of design, and it is generally not adjustable. It can only be adjusted during major repairs. However, it is very important to analyze the relative relationship between its internal components to adjust Feida. beneficial. The functions of the paper suction nozzle, the paper separation nozzle and the presser foot have been described previously. From the perspective of the transmission chain, the mutual relationship between them should be: a paper suction nozzle and a paper suction nozzle. The paper suction nozzle is an absolute reference for debugging within Feida. The paper separation suction can only be adjusted relative to the paper suction nozzle, but it is also a relative reference relative to the presser foot. In other words, when there is an incorrect fit between the paper transfer nozzle and the paper separation nozzle, the paper separation nozzle should be adjusted; when the relationship between the paper separation nozzle and the presser foot is incorrect, the pressure foot should be adjusted. This clarifies the relationship between the three components. (6) The application of the principle of symmetry in the adjustment of the paper conveying part, from Feida, paper conveying to the front gauge, it can be seen that most of the components on it appear in a symmetrical state. Because of this, the adjustment of these components must be based on the principle of symmetry, that is, position symmetry, force symmetry, and adjustment symmetry. This is the key to ensuring the normal operation of the machine. But in the actual process, the ideal symmetry does not exist, so is it normal operation will be destroyed? Actually not. Why? This is because the regulation part has the function of making up for the error of paper feeding. In fact, it is the error caused by these asymmetric factors. However, the error that can be compensated for is limited. When the paper feed error exceeds a certain level, the rules are powerless and can only give an error signal. The solution to this problem can only adopt the principle of quasi-symmetric. In actual work, each component should work in a state of quasi-symmetric principle, as close as possible to the ideal symmetry state, which is one of the first conditions for tuning. BNF HARDWARE CO., LTD , https://www.bnfhardware.cn
(2) Change the size of the gripper. In the printing process, it is sometimes necessary to change the size of the gripper. There are two ways to solve this problem: one is to borrow the roller; the other is to adjust the front and rear positions of the front rule. The amount of change in the current regulation is relatively small, and it is more convenient to move the pre-regulation.
(3) Make up for the errors of plate-making and plate-making. Plate-making and plate-making are theoretically difficult to ensure that all the images are in the standard position. Generally, the calcium of the Ministry of Love needs to be adjusted to a certain position through the micro-adjustment of the previous regulations. This is also one of the important roles of the previous regulations.
(4) During the paper feeding process, the paper enters a semi-constrained state from the free state. It can be said that the paper that arrives at the front gauge is not in the same position each time, but is brought to a certain position through the front gauge.
(5) Create conditions for the side regulation position The side regulation position is carried out on the basis of the pre-positioning position, so the pre-positioning position is the reference for the side regulation position. This can be seen from the designed press. Under normal circumstances, the front position is accurate, even if the side position is not correct, the machine will not stop, but if the previous position is not correct, the machine will automatically stop. This is because the side positioning is not accurate, but as long as the previous positioning is accurate, the printed product can sometimes be used.
(6) The paper of different types and formats can be adjusted. The printed paper changes according to the user's requirements. It cannot be the same all the time. Therefore, the pre-regulation must be able to make corresponding changes according to the different types and formats Adjust to ensure accurate paper positioning.
â‘¡When the hand gripper leaves the front gauge board, the front gauge should be put down in advance to make the paper.
â‘¢ The front gauge should not interfere with the previous paper when swinging back. To achieve these points in the front gauge, the movement of its components must be flexible, and the time and displacement should be matched accurately. At the same time, each component should have minimal crosstalk and jump. The height of the front gauge and the front and rear adjustment mechanisms are generally more complicated. The domestic equipment uses a linkage mechanism, and Heidelberg uses a three-point suspension mechanism.
(Figure 1.12)
(Figure 1.13)
â‘¡According to the change of paper thickness, relative adjustment can be made in the height direction;
â‘¢ According to the needs of transmission, the pressure of the roller on the paper should be adjustable;
â‘£According to the needs of position coordination, the angle between the side gauge baffle and the front gauge can be adjusted mutually (to make it at a right angle);
⑤According to the timing relationship, the start and end time of the side gauge pull paper should be adjustable; ⑥Selection of working and non-working state.
â‘¡ Evenly accelerated motion transfers the paper from the cardboard to the impression Cylinder or paper transfer cylinder. This requirement guarantees the smooth handover of paper with minimum inertial impact. This is the key to designing the paper delivery cam. In fact, the design of the paper delivery cam does not necessarily have to wait for acceleration or deceleration, the key is to require smooth movement and minimum inertial impact.
â‘¢The paper is handed over to the subsequent rollers relatively statically. Only relatively still can the paper handover be performed. If the paper slides relatively during the handover, the accuracy of the handover is destroyed.
â‘£ Evenly decelerating from the roller back to the cardboard. This requirement minimizes the stabilization time required when the paper is returned to the paperboard, making it enter the absolute static state as quickly as possible. This is also a key part of designing the paper delivery cam.
â‘¡ When the delivery tooth leaves the paperboard, the front rule should leave the paperboard in advance.
â‘¢ Only when the tooth pad of the delivery tooth is parallel to the tooth pad of the rear transfer roller, can the paper be delivered.
â‘£When there is a paper conveyance failure, the paper feeding tooth does not fit on the paper feeding board.
â‘¡Within the trajectory of movement, it cannot interfere with any other parts.
â‘¡ The pressure of all dental slices is the same and the contact is even.
â‘¢ The movement of all dental slices is the same.
â‘£ The opening and closing tooth mechanism is flexible and reliable.
⑤ The cross-talk and beating of the paper delivery shaft are minimum.
(Figure 1.14)
â‘¡Protection rubber: The rubber plays a role in transferring ink. If two or more sheets of paper enter the surface and are damaged, the ink transmission is destroyed and the print quality cannot be guaranteed. It is troublesome to replace or cushion the rubber.
â‘¢Protection roller row: When the bite is uneven, the paper is easy to slide in the row, and over time, it will cause the dental pad to wear, and the accuracy of the overprint will be affected.
â‘£Protect the machine: When the paper is stranded or foreign objects enter between the rollers, the machine will be suddenly impacted, and the roller surface, bearings and gears may be damaged. The interlocking mechanism can be said to be the last safety line.
â‘¡Paper-feeding teeth do not fit on the cardboard: This action is achieved by the movement of the tooth-opening cam. Regardless of the institution used, the end result is the same. After the paper delivery teeth leave the cardboard, the teeth are still closed, because the tooth row has left the paper.
â‘¢ The action process of the interlock mechanism: a. The photoelectric sensor identification signal is transmitted to the main console; b. The main console analyzes and notifies the corresponding control switch; c. The control switch starts and the actuator starts to work.
â‘¡The regulation part is adjusted relative to the registration roller (or called paper transfer tooth): when the registration roller picks up the paper on the paperboard, if the paper picking time is wrong, then only the regulation part can be adjusted, and the registration roller (paper transfer cannot be adjusted) tooth).
(Figure 1.15)