| 摘要 |
A cam mechanism is described for automatically skewing a second cylinder in a printing press, such a form roller (24), in response to skewing of a first cylinder thereof, such as a plate cylinder (12), and for throw-on/throw-off of the second cylinder. The mounting (80, 82) for each end of the second cylinder is biased against a corresponding cam (74, 76), both cams being carried on a common cam shaft (78). A linkage (90) couples the cam shaft (78) to an eccentric (52) used for skewing the first cylinder (12). Upon skewing of the first cylinder (12), the linkage (90) rotates the cam shaft (78). The profiles of the cams (74, 76) are selected to be different so that this rotation of the cam shaft (78) causes one end of the second cylinder (24) to move to a greater extent than the other end, thereby skewing it by an amount matching the skewing of the first cylinder. An actuator (108) is provided for rotating the cam shaft (78) beyond the range of positions produced by the linkage (90) for throw-off of the second cylinder. The profiles of the cams (74, 76) are selected so that such rotation causes both ends of the second cylinder (24) to move out of contact with the first cylinder (12). |
