Granted Patent B2

US 12,246,528 · App. 17/435,694 · Granted Mar 11, 2025

Inventor: Benzion Landa (Nes Ziona, IL)

Assignee: LANDA CORPORATION LTD.

B41F27/105B41F21/104B41F27/1262B41F31/16

Abstract

Claims (63)

1. A printing system comprising:

a. an intermediate transfer member (ITM) comprising a flexible belt operable to have ink images formed thereupon by droplet deposition at an image-forming station; and

b. an impression station configured for transfer of the ink image to substrate after they are conveyed to the impression station by the ITM, the impression station comprising:

i. a rotatable impression cylinder having a cylinder gap that houses a plurality of grippers spaced along a gripper shaft so as to define a plurality of inter-gripper regions, each gripper of the plurality of grippers being disposed in the cylinder gap of the impression cylinder;

ii. a jacket disposed around a portion of the circumference of the impression cylinder, the jacket comprising multiple tab portions; and

iii. a jacket-securing arrangement for securing a tab portion of the jacket to the rotatable impression cylinder, the jacket-securing arrangement comprising:

a. a magnet;

b. a first member, configured for holding the magnet; and

c. a second member, detachably attachable to the first member, the first and the second members being adapted to be rotatably mounted around the gripper shaft when disposed in an assembled state in one of the inter-gripper regions,

wherein when in said assembled state, the jacket-securing arrangement is configured to magnetically secure the jacket tab portion to the impression cylinder when in a first rotated position and not to magnetically secure the jacket tab portion to the impression cylinder when in a second rotated position, and

wherein a plurality of the jacket-securing arrangements is arranged to secure a corresponding plurality of the jacket tab portions to a surface of the cylinder gap, said plurality of jacket-securing arrangements being disposed in said respective assembled states within the cylinder gap such that each jacket-securing arrangement of the plurality of jacket-securing arrangements is disposed in a respective inter-gripper region.

2. The printing system of claim 1 , wherein magnetically securing the jacket tab portion to the impression cylinder includes magnetically securing the jacket tab portion to a surface of the cylinder gap.

3. The printing system of claim 1 , wherein at least one of the first and second members has a respective volume for receiving a part of the circumference of the gripper shaft.

4. The printing system of claim 1 , wherein:

i. the impression cylinder comprises a second impression cylinder gap and a second plurality of grippers housed therewithin and spaced along a second gripper shaft so as to define a second plurality of inter-gripper regions,

ii. the impression station additionally comprises (A) a second jacket disposed around a second portion of the circumference of the cylinder, the second jacket comprising multiple tabs, and (B) a second plurality of jacket-securing arrangements for securing a corresponding plurality of the tabs of the second jacket to the cylinder, each jacket-securing arrangement comprising respective first and second members that am reversibly attachable to each other, each respective first member holding a magnet, and

iii. when the jacket-securing arrangements of the second plurality of jacket-securing arrangements are in respective assembled states and rotatably mounted around the second gripper shaft in respective inter-gripper regions, said jacket-securing arrangements are operative to reversibly secure corresponding tabs of the second jacket magnetically to a surface portion of the second cylinder gap.

5. An installation method comprising:

a. arranging a Jacket on an impression cylinder, the impression cylinder comprising a cylinder gap and a plurality of grippers disposed therewithin, the plurality of grippers housed by the cylinder gap and spaced along a gripper shaft so as to define a plurality of inter-gripper regions, the jacket having a plurality of tab portions extending therefrom, such that each of the tabs is disposed in a corresponding inter-gripper region, the impression cylinder further comprising a jacket-securing arrangement comprising:

A. a magnet;

B. a first member, configured for holding the magnet; and

C. a second member, detachably attachable to the first member, the first and the second members being adopted to be rotatably mounted around the gripper shaft when disposed in an assembled state in one of the Inter-gripper regions,

wherein when in said assembled state, the jacket-securing arrangement is configured to magnetically secure the jacket tab portion to the impression cylinder when in a first rotated position and not to magnetically secure the jacket tab portion to the impression cylinder when in a second rotated position; and

b. rotating at least one of a plurality of the jacket-securing arrangements around the gripper shaft so as to magnetically secure a corresponding one or more of the jacket tabs to the cylinder gap,

wherein the method is performed such that the plurality of the jacket-securing arrangements is disposed in said respective assembled states within the cylinder gap such that each jacket-securing arrangement of the plurality of jacket-securing arrangements is disposed in a respective inter-gripper region.

6. A printing system comprising:

a. an intermediate transfer member (ITM) comprising a flexible belt operable to have ink images formed thereupon by droplet deposition at an image-forming station; and

b. an impression station configured for transfer of the ink images to substrate after they are conveyed to the impression station by the ITM, the impression station comprising:

i. a rotatable impression cylinder having a cylinder gap that houses a plurality of grippers spaced along a gripper shaft so as to define a plurality of inter-gripper regions, each gripper of the plurality of grippers being disposed in the cylinder gap of the impression cylinder;

ii. a jacket disposed around a portion of the circumference of the impression cylinder, the jacket comprising multiple tab portions; and

iii. a jacket-securing arrangement for securing a tab portion of the jacket to the rotatable impression cylinder, the jacket-securing arrangement comprising:

a. a first member having a magnet affixed thereto; and

b. a second member, detachably attachable to the first member, the first and the second members being adapted to be rotatably mounted around the gripper shaft when disposed in an assembled state in one of the inter-gripper regions,

wherein (i) when disposed in said assembled state in said one of the inter-gripper regions, the jacket-securing arrangement is configured to magnetically secure the jacket tab portion to the impression cylinder when in a first rotated position, and (ii) when the jacket-securing arrangement is in the first rotated position, application of a force at a respective force-receiving surface is effective to release the jacket tab portion from being secured magnetically by causing the jacket-securing arrangement to rotate from the first rotated position to the second rotated position, and

wherein a plurality of the jacket-securing arrangements is arranged to secure corresponding jacket tab portions to the impression cylinder, said plurality of jacket-securing arrangements being disposed in said respective assembled states within the cylinder gap such that each jacket-securing arrangement of the plurality of jacket-securing arrangements is disposed in a respective inter-gripper region.

7. The printing system of claim 6 , wherein when the magnet is in the first rotated position, it is in contact or near contact with a magnet target location on a surface portion of the cylinder gap.

8. The printing system of claim 7 , wherein when the magnet is in the second position, it is out of contact or near contact with the magnet target location on said surface portion of the cylinder gap.

9. The printing system of claim 7 , wherein the force-receiving surface is being within +/−30° of perpendicular to said surface portion of the cylinder gap and the force is in a direction that is within +/−30° of parallel to said surface portion of the cylinder gap.

10. The printing system of claim 7 , the force-receiving surface being within +/−15° of perpendicular to said surface portion of the cylinder gap and the force is in a direction that is within 1+/−15° of parallel to said surface portion of the cylinder gap.

11. The printing system of claim 6 , wherein

a. the jacket comprises N tabs TAB( 1 ) . . . TAB(N)extending from a first end of the jacket, each of the N tabs TAB(n)having a respective width value TAB-WIDTH(n) and a respective spacing value TAB-SPACING(n),

b. the plurality of gripper-regions includes a subset of N inter-gripper regions REGION( 1 ) . . . REGION(N) corresponding to the N tabs, each of the N inter-gripper regions REGION(n) of the subset having a respective width value REGION-WIDTH(n) and a respective spacing value REGION-SPACING(n),

c. the arranging of the jacket on the cylinder is such that TAB( 1 ) is in REGION( 1 ), and TAB(N) is in REGION(N), and

d. for each value of n from 1 to N, TAB-WIDTH(n) is not greater than REGION-WIDTH(n), and TAB-SPACING(n) is substantially equal to REGION-SPACING(n).

12. The printing system of claim 6 , wherein:

i. each force-receiving surface is a surface of a force-receiving portion having a thickness that is variable in a direction that is radial with respect to the gripper shaft,

ii. for the plurality of jacket-securing arrangements, not all of the force-receiving portions have the same variable thickness, such that no more than three force-receiving portions have the same variable thickness, the differences in variable thickness being in a direction that is substantially normal to a longitudinal axis of the gripper shaft, and

iii. when the jacket-securing arrangements ae in said respective assembled states and in the first rotated position, the differences in variable thickness are such that not all of the force-receiving surfaces re disposed at the same angle of rotation with respect to the gripper shaft.

13. An installation method comprising:

a. arranging a jacket on an impression cylinder, the impression cylinder comprising a cylinder gap and a plurality of grippers disposed therewithin, the plurality of gripers housed by the cylinder gap and spaced along a gripper shaft so as to define a plurality of inter-gripper regions, the jacket having a plurality of tab portions extending therefrom, such that each of the tabs is disposed in a corresponding inter-gripper region, the impression cylinder further comprising a jacket-securing arrangement comprising:

i. a first member having a magnet affixed thereto; and

ii. a second member, detachably attachable to the first member, the first and the second members being adapted to be rotatably mounted around the gripper shaft when disposed in an assembled state in one of the inter-gripper regions,

wherein (A) when disposed in said assembled state in said one of the inter-gripper regions, the jacket-securing arrangement is configured to magnetically secure the jacket tab portion to the impression cylinder when in a first rotated position, and (B) when the jacket-securing arrangement is in the first rotated position, application of a force at a respective force-receiving surface is effective to release the jacket tab portion from being secured magnetically by causing the jacket-securing arrangement to rotate from the first rotated position to the second rotated position; and

b. rotating at least one of a plurality of the jacket-securing arrangements around the gripper shaft so as to magnetically secure a corresponding one or more of the jacket tabs to a surface portion of the cylinder gap,

wherein the method is performed such that the plurality of the jacket-securing arrangements it disposed in said respective assembled states within the cylinder gap such that each jacket-securing arrangement of the plurality is disposed in a respective inter-gripper region.

14. A method for replacing a cylinder jacket on an impression cylinder comprising a cylinder gap and a plurality of gripper disposed therewithin, the plurality of grippers housed by the cylinder gap and spaced along a gripper shaft so as to define a plurality of inter-gripper regions, the impression cylinder further comprising a jacket-securing arrangement comprising (i) a first member having a magnet affixed thereto; and (ii) a second member, detachably attachable to the first member, the first and the second members being adapted to be rotatably mounted around the gripper shaft when disposed in an assembled state in one of the inter-gripper regions, wherein (A) when disposed in said assembled state in said one of the inter-gripper regions, the jacket-securing arrangement is configured to magnetically secure the jacket tab portion to the impression cylinder when in a first rotated position, and (B) when the jacket-securing arrangement is in the first rotated position, application of a force at a respective force-receiving surface is effective to release the jacket tab portion from being secured magnetically by causing the jacket-securing arrangement to rotate from the first rotated position to the second rotated position, a plurality of the jacket-securing arrangements being disposed in said respective assembled states within the cylinder gap such that each jacket-securing arrangement of the plurality is disposed in a respective inter-gripper region, wherein the cylinder jacket comprises a plurality of tabs extending therefrom along an edge of the jacket, and the jacket-securing arrangements are in a first rotated position such that the jacket tabs am magnetically secured to a surface portion of the cylinder gap, the method comprising:

a. applying a force to rotate the jacket-securing arrangements to a second rotated position and thereby release the jacket tabs from being magnetically secured to said surface portion;

b. removing the jacket from the cylinder;

c. providing a replacement jacket comprising a plurality of tabs;

d. arranging the replacement jacket on the impression cylinder, such that each of the tabs is disposed in a corresponding inter-gripper region, and

e. rotating each of the jacket-securing arrangements around the gripper shaft to the first rotated position, so as to magnetically secure each of the tabs of the replacement jacket to said surface portion of the cylinder gap.

15. The method of claim 14 , wherein the force applied to the force-receiving surfaces is applied using a substantially straight, rigid bracket held substantially parallel to the gripper shaft, the applying of force being effective to cause rotation of the jacket-securing arrangements from the first rotated position to the second rotated position in a sequence that begins with rotation of the jacket-securing arrangements having the force-receiving portions with the largest variable thickness and that ends with rotation of the jacket-securing arrangements having the force-receiving portions with the smallest variable thickness.

16. The method of claim 15 , wherein the rigid bracket includes a plurality of protrusions, and each of the force-receiving portions having the largest variable thickness includes a protrusion-receiving portion for receiving a respective one of the plurality of protrusions.

Assignments (4)

Priority Claims (1)

Continuity (1)

References Cited (52)