Analysis of clutch press mechanism of offset press (2)

Three points are used to reset the drum, even if the drum is stable in every new position. The 3-point structure consists of a powerful spring and a circular wheel. When the convex sleeve 4 leaves the circular wheel, the spring elongates to keep the circular wheel in contact with the convex sleeve. When the convex sleeve pushes the circular wheel, the spring is compressed. Regardless of the change in the position of the convex sleeve, the three points are always in contact with the convex sleeve, and therefore the three-point positioning principle of the plane is always satisfied. This positioning relationship must be absolutely guaranteed. In addition to the above-mentioned effects, the 3 point spring also has the effect of buffering vibration absorption, so that the machine can run more smoothly.

At three points, the County Floating Lifting and Pressing Mechanism has almost no requirements for wallboard holes, which brings great convenience to the processing of wallboard holes. Less pressure adjustment and high accuracy. And easy adjustment. Due to the presence of weak links, it can play a role in protecting the machine. However, the installation and commissioning of this clutch-pressing mechanism is troublesome. Without dedicated tools and rich experience, it is difficult to ensure its accuracy. Because there are only three points of contact, the contact surface is relatively small, so the impact resistance is poor, and it is not suitable for large printing pressure.

(2) eccentric sleeve type clutch pressure mechanism

As shown in Figure 2.8, 1 is a blanket cylinder, 2 is an eccentric sleeve, 3 is a wall plate, and 4 is a connecting rod. At the time of clutch pressure, the connecting rod 4 pushes the eccentric sleeve 2 to rotate. The outer circle of the eccentric sleeve 2 does not move, and coincides with the center of the wall plate hole 3, but the center position of the inner hole of the eccentric sleeve 2 changes. Since the center of the inner hole coincides with the axis of the blanket cylinder, the axis of the blanket cylinder also changes with the position of the inner hole of the eccentric sleeve, which changes the distance between the blanket cylinder 1 and the plate cylinder and the impression cylinder. The clutch pressure is achieved.

The eccentric sleeve type clutch pressure mechanism has a large contact area between the eccentric sleeve 2 and the wall plate hole 3, so its impact resistance is strong, and the eccentric sleeve has a round shape inside and outside, so the transition is smoother than the convex sleeve and the clutch pressure When the impact is small. This kind of clutch pressure mechanism has a rather high requirement for wallboards, which brings great difficulties to the processing of wallboards. Because the offset of the eccentric sleeve increases more slowly than the offset of the convex sleeve, the eccentric sleeve type clutch pressure mechanism needs more space for movement, which brings about great installation of Other components on the wallboard. inconvenient. Another disadvantage of this structure is that there are no weak links, so the shaft and wall plate holes are damaged when accidentally hit. Once damaged, it is difficult to repair.