Claims
- 1. A sheet-fed offset printing machine comprising: a rotatable cylinder; a washing device having a housing; a washing roller mounted within the housing and operable to engage the rotating cylinder and disengage from the cylinder at predetermined fixed angular settings of the rotating cylinder; an angle generator, the angle generator including a sensor and a real-time computer, the angle generator further providing trigger signals corresponding to angles; and a controller responsive to the trigger signals provided by the angle generator by performing a plurality of control operations, the control operations including (a) spraying the washing roller with a cleaning fluid, and (b) increasing, following spraying of the washing roller, the rotary speed of the cylinder, while the cylinder is disengaged from the washing roller, for further cleaning the cylinder.
- 2. A printing machine according to claim 1, wherein the angle generator differentiates the angular setting of the rotation cylinder to be cleaned between one and a plurality of cylinder revolutions.
- 3. The printing machine according to claim 1, further comprising operating cylinders coupled to the washing roller for moving the washing roller and nozzles for supplying cleaning fluid and water to the washing roller, and wherein the controller is coupled to the operating cylinders and the nozzles of the washing device.
- 4. The printing machine according to claim 1, wherein the controller commands nozzles to periodically spray the washing roller with detergent or water at a first angular setting, the first angular setting corresponding to a position on the cylinder prior to a first edge of a cylinder gap of the cylinder, and the washing roller engages the cylinder at a second angular setting corresponding to a position on the cylinder at the first edge of the cylinder gap.
- 5. The printing machine according to claim 4, wherein during a washing cycle, a wedge of fluid, including detergent water and soil deposits, is deposited in a circular sector between the third and fourth angular settings and is removed from the outer surface of the cylinder by the washing device during the drying cycle, the third angular setting corresponding to a position on the cylinder prior to a second edge of the cylinder gap and the fourth angular setting corresponding to a position on the cylinder at the second edge of the cylinder gap.
- 6. The printing machine according to claim 1, wherein the controller increases the rotary speed of a cleaned cylinder after the end of a washing and drying cycle.
- 7. The printing machine of claim 1 in which said washing roller is a washing brush.
- 8. The printing machine of claim 1 in which said washing roller has a soft outer surface.
- 9. The printing machine of claim 1 in which said washing roller has a washing cloth.
Priority Claims (1)
Number |
Date |
Country |
Kind |
44 43 356 |
Dec 1994 |
DEX |
|
Parent Case Info
This application is a continuation of Ser. No. 08/568,370, filed Dec. 6,1995, now U.S. Pat. No. 5,753,048.
US Referenced Citations (8)
Foreign Referenced Citations (8)
Number |
Date |
Country |
0 4004605 |
Oct 1979 |
EPX |
0 419289 |
Aug 1991 |
EPX |
0548500 |
Oct 1992 |
EPX |
1808909 |
Mar 1974 |
DEX |
26 13687 |
May 1979 |
DEX |
41 42422 |
Jun 1993 |
DEX |
42 16243 |
Nov 1993 |
DEX |
43 43692 |
Jun 1995 |
DEX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
568370 |
Dec 1995 |
|