(This article is an original article from Bisheng. It is forbidden to reprint, and reprinting must be corrected)
The J2108 and J2205 printing machines have been widely used in China for many years due to low factory prices and stable printing quality. However, due to the relatively complicated design of many machines, we often encounter many troubles in our use. The adjustment and troubleshooting of the positioning mechanism of the two models reflect the most problems. In response to this phenomenon, this article will focus on the front and side regulations of these two models.
The structure of the front and side gauges of the J2108 and J2205 machines are basically the same, so they are introduced together in this article.
The working structure and working principle of the pre-regulation
Figure 1 shows the structure of the front gauge of the J2108 machine. The front paper positioning plate is fixed on the gauge seat with screws 19, and the gauge seat is fixed to the front gauge shaft 13 through the retaining ring. The movement of the front gauge is controlled by the cam 1 mounted on the end face (operating face) of the transmission gear of the eccentric bearing of the delivery tooth swing shaft.
The model J2108 adopts a combined upper swing type front gauge. Figure 2 shows its working principle:
Figure 1 J2108 pre-regulation structure
The cam 1 swings the swing lever 2 up and down via the roller; the tension spring 3 keeps the roller in contact with the cam. The sliding sleeve 4 moves the connecting rod 7 up and down with the swing rod 2 via the pressure spring 5 and the adjusting nut 6. The swing rods 8 and 9 are fixed together and looped on the front axle 13. The lower end of the swing rod 9 has a looper 10, which can move back and forth on the connecting rod equipped with the pressure spring 14, and the movement is transmitted to the swing rod 12 and the front gauge shaft 13 by the support spring 14 and the adjusting nut 11 There is a row (4 pcs) of front paper positioning plates 17 on each. Each positioning plate has a fixing screw 16 to fix the front gauge frame 21 on the shaft 13. When the swing lever 12 swings, the front gauge blocks paper The positioning plate 17 swings up and down together with the seat frame 21 via the shaft 13.
Figure 2 The working principle of the front gauge of J2108
When the cam is in contact with the roller at the high point of the stationary arc, the front gauge is in the positioning position shown in the figure, and when the curved surface of the cam changes from the high point to the low point. The swing rod 2 swings down, the support spring 5 and the nut 6 and the connecting rod 7 go down together, and the swing rods 8 and 9 are rotated clockwise around the front axle 13, and the connecting rod 7 is driven to move together through the spring 14 and the nut 11 to fix The seat frame 21 on the front gauge shaft together with the positioning plate 17 is lifted clockwise to the paper letting position.
When the cam 1 moves from a high point to a low point, the swing lever 8 is in contact with the positioning pin 22 to block its upward swing motion. At this time, the cam continues to rotate towards the high point, the sliding sleeve 4 on the swing lever 2 slides on the connecting rod 7 and compresses the support spring 5, and the front gauge paper positioning plate 17 is stabilized at a stationary position due to the positioning pin 22 Location. Even if there is machining error on the cam curve surface, it can also make the front gauge paper positioning plate stable, so as to achieve the purpose of stabilizing the paper on the paper conveying table and ensure the accuracy of the previous position.
The swing lever 23 is automatically controlled by the roller clutch mechanism. During normal operation, the swing lever 23 is at the position shown in the figure, and the front gauge can swing freely. When faults such as empty sheets and paper skew occur, the circuit is connected, the electromagnet swings the swing lever 23 to the left under the looper 10, the swing lever 9 cannot swing, the front rule cannot lift up the paper, and the paper table Paper that is not properly positioned on the top will not be bitten into the roller by the delivery teeth. In this case, the roller on the swing lever 2 will be out of contact with the cam low point.
The movement time of the front gauge depends on the coupling position of the cam 1 and the eccentric bearing transmission gear of the delivery tooth swing shaft, that is, at the position of the machine at the "0" point (J2108, J2205 models stipulate that the impression cylinder can start biting the paper when biting It is the "0" point of the host). The "0" line of cam 1 is in contact with the roller (the position shown in Figure 1). Since the position of the cam has been debugged by the manufacturer, it is fixed with a pin, and it is generally no longer adjusted during use. If, after overhauling the machine, it is found that the front gauge is not suitable for the paper, then the cam 1 can be borrowed.
The most common adjustment of the front gauge is the adjustment of the front and back and height of the paper blocking positioning plate 17. The front and rear adjustment is used when the printing plate needs to be slightly adjusted in the circumferential direction or it is inconvenient to pull the printing plate. At this time, the front gauge can be adjusted. Loosen the lock nut 19. By turning the adjusting screw 18, the positioning plate 17 can be moved back and forth, and the nut 19 is locked after the adjustment. The adjustment principle of the front and rear position is to adjust as little or as little as possible to ensure that the bite distance of the roller teeth is equal on both sides.
The height of the positioning plate can be adjusted according to the thickness of the paper. In general, when the front gauge is in the positioning position, the gap between the bottom surface of the curved surface of the positioning plate and the plane of the feeding plate should be three times the thickness of the printed paper. For individual adjustment, first loosen the screw 16 that fixes the front gauge frame, hold the front gauge by hand to adjust its height, and then tighten the fixing screw 16 after adjustment. If the overall adjustment is possible, first loosen the lock nut 24, then turn the adjustment nut 20, change the height of the connecting rod 7, deflect the front gauge shaft 13 by an angle, and drive the positioning plate up or down. There should be a gap of 0.1 mm between the adjusting nut 20 and the sliding sleeve 4 at the previous position to ensure that the eccentric cutting shaft 22 and the rod 8 are tight. The gap can not be large, too large will increase the positioning time.
The structure and working principle of side gauge
J2108, J2205 and PZ4880-01 models all use roller side gauges. Figure 3 is a schematic diagram of the structure of the side gauge.
Figure 3 Principle diagram of the side gauge structure of J2108 machine
The side gauge transmission shaft I is equipped with a cam 9 and a gear 14, the cam 9 and the gear 14 are coupled to the shaft through a flat key, and their positions on the shaft are controlled by the side gauge seat body 17. The fixed shaft 18 is sleeved with a sleeve seat 19, which can be fixed with the handle 6 on the upper end of the screw rod after moving together with the entire side gauge, and then the seat body 17 of the side gauge and the fixed shaft 18 are fixed together by a nut 27.
The rotary motion of the paper pulling wheel is driven by the gear 14, the gear 15 and the bevel gear 22 are coupled together, so the bevel gear 22 also gets rotated, and the transmission bevel gear 16 makes the paper pulling wheel 1 obtain the rotary motion.
The up and down swing of the paper ball is caused by the cam 9 through the roller 10 swinging the swing lever 20 back and forth around the pivot point O. A swing paper ball 2 is fixed to the swing arm extending from the swing lever 20. Oscillating and oscillating up and down, the compression spring 21 brings the roller 10 into contact with the cam surface. When pulling paper, the compression spring 21 in turn causes the pulling ball and the pulling wheel to obtain contact pressure.
There are four aspects to the regulation of side regulation:
1. The adjustment of the side gauge pulling time
After the front gauge positions the paper, the side gauge starts to pull the paper. At this time, the paper-pulling ball should drop and come into contact with the paper-pulling wheel. There are three methods for adjusting the pulling time.
(1) Simultaneous adjustment of the left and right side gauges:
On the outside of the transmission surface of the transmission shaft I, a flange is installed on the end of the shaft. There are three screw holes on the end surface of the piece, which are connected to a transmission gear through the three screw holes, and there are long holes on the gear. The relative position of the circumference of the shaft can change the time when the side gauge pulls the paper, so that the two rules on the left and right sides can be adjusted synchronously.
(2) Coarse adjustment of a single side gauge: if you only need to change the pulling time of one side gauge, you can loosen the fixing screw on the cam 9 and adjust the relative position of the cam and the shaft circumference to make the pulling time larger Adjust.
(3) Fine adjustment of a single side gauge: the roller 10 and the paper pulling roller are fixed by the eccentric shafts 11 and 13, respectively, and the eccentric position of the eccentric shaft can be adjusted. The fine adjustment is essentially to change the gap between the roller 10 and the low point of the cam curve surface after the paper ball is dropped and comes into contact with the paper wheel. If the gap is large, the paper roller will fall early and be lifted late; otherwise, the paper roller will fall late and be lifted early.
2. Adjustment of working position of paper stopper
The paper blocking positioning plate is fixed with the swing lever 20 when it is working, so it swings up and down simultaneously with the paper ball. The paper stopper is connected with the screw rod 23 and slides in the sleeve 24. They are fixed together by the positioning pin 26 and the adjusting nut 4 and the lock nut 5. The sleeve 24 is installed in the hole of the swing rod 20, by The lock nut 3 is tightened. Loosen the nut 3 to fix 4, 23, 5, 26, 24 and 25 fixed to each other in the hole of the swing rod 20, which can adjust the perpendicularity of the baffle positioning plate to the front specified plane .
The gap between the paperboard and the paper transport table is 3 times the thickness of the printing paper. During adjustment, loosen the nut 5 and turn the adjusting nut 4 to move the screw 23 to drive the paperboard 25 in the sleeve 24 with external thread to change the gap between the paperboard and the paper conveying table. Since the pitch of the coupling portion between the nut 4 and the sleeve 24 is large, and the pitch of the coupling portion with the screw rod 23 is small, when the nut is turned, the difference between the two threads is used for adjustment. When the nut 5 rotates once, the height movement of the paperboard is the difference between the two pitches.
3. Adjustment of paper pulling force
The contact pressure of the paper pulling roller is obtained by adjusting the screw 7 to change the deformation amount of the compression spring 21. According to the thickness of the printed paper, the side gauge is equipped with two kinds of compression springs (one with a larger spring force and the other with a smaller spring force), which can be replaced as needed.
4. Adjustment of the working position of side regulation
Loosen the lock nut 27, loosen the screw 28 with the handle 6, and change the axial position of the sleeve seat 19 on the fixed shaft 18. The entire side gauge is moved so that the side gauge is greatly adjusted in the "left and right" direction. For fine adjustment, the lock nut 27 is loosened, and the screw 8 is rotated, so that the side gauge base 17 and the fixed shaft 18 are relatively moved to make slight adjustments. The maximum pulling amount of the side rule is 12 mm. Under normal circumstances, the side stopper positioning plate is preferably 5 to 8 mm from the side of the paper.
There are two side rules, installed symmetrically, but only one is used for printing, and the other should stop working. That is, the swing lever 20 is pushed by locking the eccentric 12, so that the paper pulling ball is lifted up without contacting the paper pulling wheel.
The following is an analysis of some problems that are likely to occur in the work of side regulations and pre-regulations.
1. The front rules of J2108 and J2205 offset presses are generally not suitable for four (or two) height adjustments at the same time, and daily operations can only be performed separately.
2. The front board stops the paper board at the bottom and hinders the paper transmission, which can easily cause the paper to "underrun".
3. The paper board on the front gauge is too high, which may cause the paper edge to curl and cause the paper to "walk over".
4. The front and rear positions of the two front gauges are adjusted too much, and the positioning line is not parallel to the bus bar of the impression cylinder, which may easily cause gripping paper or overprint failure.
5. The pre-regulation is often used, and the positioning and blocking board is easy to be worn, causing inaccurate positioning of "up and down".
6. When one of the following conditions occurs, it is easy to cause the side rule "insufficient pull":
(L) The distance between the paper and the positioning stopper of the side gauge is too large;
(2) The drawing time of the side gauge is too short;
(3) The pressure of the side gauge pull roller is insufficient, and the pull force is light;
(4) The blocking board on the side gauge is too low;
(5) The pressure of the paper pressing mechanism on the paper feeding table is too heavy;
(6) Paper jam or debris are embedded in the side stopper.
7. When one of the following conditions occurs, it is easy to cause the side rule to "pull too far":
(L) The pressure of the side gauge paper pulling roller is too high, or the paper board on the side gauge is too high, or the distance between the paper and the side board is too close, the paper quality is too soft, etc.
(2) The positioning line formed by the side gauge blocking paper and the front gauge blocking paper is not at right angles, so that the edge of the paper and the side gauge blocking paper are in "point" contact.
(3) The side gauges are often used, and the positioning stopper is worn, causing the positioning to come and go incorrectly.
Sichuan Soper Science & Technilogy Co., Ltd , https://www.Soper.com.cn