Printing unit with releasable bearing clamp

Abstract

A printing unit (10) includes a blanket cylinder (20), a bearing assembly (56) and a door assembly (72). The blanket cylinder (20) carries a tubular printing blanket (36). The bearing assembly (56) includes a bearing housing (58) fixed to the stub shaft (50) on the end of the blanket cylinder (20). The door assembly (72) includes a door (82) which is supported for pivotal movement on a frame wall (22) of the printing unit (10). The door (82) has a closed position in which it extends across an opening (76) in the frame wall (22), and an open position in which it does not extend across the opening (76) in the frame wall (22). A clamping assembly clamps the bearing housing (58) on the door (82) when the blanket cylinder (20) rotates during a printing operation. The clamping assembly includes a first clamp (100) which fixed to the door (82) and a second clamp (102) which is supported on the door (82) for movement relative to the first clamp (100). The first clamp (100) is engaged with the bearing housing (58) when the door (82) is closed. The second clamp (102) is movable into and out of engagement with the bearing housing (58) when the door (82) is closed. The door assembly (72) is movable with the blanket cylinder (20) for throw-off.

Having described the invention, the following is claimed: 
     
       1. Apparatus comprising: a rotatable printing cylinder (20) having a cylinder axis (52);   a bearing assembly (56) for supporting said cylinder (20) to rotate about said cylinder axis (52), said bearing assembly (56) including a bearing (59) supported on said cylinder (20);   a frame wall (22) having a surface means (74) defining an opening (76);   a door (82) supported on said frame wall (22) for movement relative to said frame wall (22), said door (82) being movable between a closed position in which said door (82) extends across said opening (76) and an open position in which said door (82) does not extend across said opening (76); and   clamping means for releasably clamping said bearing (59) on said door (82), said clamping means including first and second clamps (100, 102) supported on said door (82) for movement with said door (82) relative to said frame wall (22), said clamps (100, 102) being movable relative to each other between clamping positions in which said clamps (100, 102) hold said bearing (59) on said door (82) and releasing positions in which said clamps (100, 102) release said bearing (59) from said door (82).   
     
     
       2. Apparatus as defined in claim 1 wherein said door (82) is supported on said frame wall (22) for pivotal movement about a horizontal throw-off axis (84) when said door (82) is in said closed position. 
     
     
       3. Apparatus as defined in claim 2 wherein said first clamp (100) is fixed to said door (82), said second clamp (102) being supported on said door (82) for movement relative to said first clamp (100), said first clamp (100) being engaged with said bearing (59) when said door (82) is in said closed position, said second clamp (102) being movable into and out of engagement with said bearing (59) when said door (82) is in said closed position. 
     
     
       4. Apparatus as defined in claim 3 wherein said bearing assembly (56) further includes a bearing housing (58) containing said bearing (59), said first and second clamps (100, 102) engaging said bearing (59) through said bearing housing (58) when in said clamping positions. 
     
     
       5. Apparatus as defined in claim 4 wherein said bearing housing (58) has a cylindrical outer surface, said first clamp (100) having a semi-cylindrical clamping surface (104) which fits closely against said cylindrical outer surface on one side of said bearing housing (58) when said first clamp (100) is engaged with said bearing housing (58), said second clamp (102) having a semi-cylindrical clamping surface (106) which fits closely against said cylindrical outer surface on the opposite side of said bearing housing (58) when said second clamp (102) is engaged with said bearing housing (58). 
     
     
       6. Apparatus as defined in claim 1 wherein said clamping means further comprises a first pressure cylinder (130) mounted on said door (82), a first piston rod movable (132) in said first pressure cylinder (130), and linkage means (105) for connecting said second clamp (102) with said first piston rod (132), said linkage means (105) moving said second clamp (102) relative to said first clamp (100) in response to movement of said first piston rod (132) in said first pressure cylinder (130). 
     
     
       7. Apparatus as defined in claim 6 wherein said linkage means (105) has an over-center condition in which said second clamp (102) is held in engagement with said bearing (59) independently of pressure in said first pressure cylinder (130). 
     
     
       8. Apparatus as defined in claim 6 further comprising a second pressure cylinder (140) mounted on said frame wall (22), a second piston rod (142) movable in said second pressure cylinder (140), and means for connecting said door (82) with said second piston rod (142), said connecting means moving said door (82) between said open and closed positions upon movement of said second piston rod (142) in said second pressure cylinder (140). 
     
     
       9. Apparatus as defined in claim 8 wherein said second pressure cylinder (140) is supported for pivotal movement about said horizontal throw-off axis (146) with said door (82). 
     
     
       10. Apparatus as defined in claim 1 wherein said clamping means permits said bearing (59) to move axially relative to said first and second clamps (100, 102) under the influence of thermal expansion of said cylinder (20) when said first and second clamps (100, 102) are in said clamping portions. 
     
     
       11. Apparatus as defined in claim 1 wherein said bearing assembly (56) further includes a bearing housing (58) containing said bearing (59), said bearing housing (58) being supported on said cylinder (20) to move into and out of coaxial alignment with said cylinder (20) when said door (82) is in said open position, said first and second clamps (100, 102) engaging said bearing (59) through said bearing housing (58) when in said clamping positions, at least one of said clamps (100, 102) being movable against said bearing housing (58) to move said bearing housing (58) into coaxial alignment with said cylinder (20) when moving from said releasing position to said clamping position. 
     
     
       12. Apparatus as defined in claim 1 wherein said bearing assembly (56) further includes a bearing housing (58) containing said bearing (59), said bearing housing (58) being supported on said cylinder (20) and axially fixed relative to said cylinder (20). 
     
     
       13. Apparatus as defined in claim 12 wherein said being assembly (56) further includes means for sealing said bearing housing (58) from the entry of contaminants. 
     
     
       14. Apparatus as defined in claim 12 further comprising lubricating means for lubricating said bearing (59), said lubricating means including a passage (210) for directing a lubricant to flow from said door (82) to said bearing (59). 
     
     
       15. Apparatus as defined in claim 14 wherein said passage has a portion (212) extending through said door (82) and a portion (216) extending through said bearing housing (58). 
     
     
       16. Apparatus as defined in claim 12 wherein said bearing housing (58) is supported on said cylinder (20) to rotate about said cylinder axis (52) relative to said cylinder (20), and further comprising means (200) for blocking rotation of said bearing housing (58) relative to said cylinder (20) when said door (82) is in said closed position. 
     
     
       17. Apparatus as defined in claim 16 wherein said means (200) for blocking rotation includes a spring loaded ball detent engagable between said door 82 and said bearing housing (58). .Iadd. 
     
     
       18.  Apparatus comprising: a rotatable printing cylinder (20) having a cylinder axis (52);   a bearing assembly (56) for supporting said cylinder (20) to rotate about said cylinder axis (52), said bearing assembly (56) including a bearing (59) supported on said cylinder (20);   a frame wall (22) having a surface means (74) defining an opening (76);   a door (82) supported on said frame wall (22) for movement relative to said frame wall (22), said door (82) being movable between a closed position in which said door (82) extends across said opening (76) and an open position in which said door (82) does not extend across said opening (76); and   first and second clamps (100, 102) movable relative to each other between clamping positions in which said clamps (100, 102) hold said bearing (59) and releasing positions in which said clamps (100, 102) release said bearing (59);   said second clamp slidingly moveable into and out of engagement with said bearing in a direction perpendicular to the cylinder axis. .Iaddend..Iadd.19. The apparatus as recited in claim 18, wherein the second clamp has a semi-cylindrical clamping surface. .Iaddend..Iadd.20. The apparatus as recited in claim 18, wherein the second clamp abuts the first clamp in its clamping position. .Iaddend..Iadd.21. The apparatus as recited in claim 18, further comprising a tubular printing blanket for placement onto the rotatable printing cylinder through the opening. .Iaddend.