Applies to

Lotem^® 800 VL

FCO Kit number: 512-02635

Machine S/N:

Estimated implementation time: 2 hours

Logistics: See Action required.

Type of change: Conditional

Reason: To curtail repeated problems with pressure marks that are caused by the unload rollers.

Description: Replaces the standard unload roller assembly with an unload roller assembly that includes a single roller.

Component

Unload roller assembly

Problem

The currently installed unload rollers exert too much pressure on the plates. This causes a repeated problem with pressure marks.

Solution

This FCO reduces the number of repeated service calls for recurring pressure marks, and increases machine reliability by replacing the current unload roller assembly with one that has only one roller.

Parts needed

Procedure

This procedure includes the following steps:

1. Removing the currently installed unload roller assembly
2. Assembling the single-roller unload roller assembly
3. Installing the unload roller assembly
4. Testing unload roller function

Removing and disassembling the currently installed unload roller assembly

1. Release the cassette and remove it from the machine.
2. Open the front door, right side door, left side door, and the rear door.
3. From the PC Controller, close the Lotem application.
4. Shut down the machine and disconnect it from the main power supply.
5. Close the air supply valve on the wall air pressure unit.
6. From the front of the machine, remove the unload roller piston.
7. From the rear of the machine, disconnect the following:
   Note: Cut and remove plastic ties, as required.
   • Two side-to-side detector connectors, one each on the right and left of the unload roller base. When unplugging the side-to-side detector connector, follow the wires from the detector until you locate the connector. You may need to open the right, side panel and/or the left, side door for better access:
     
     

   • Unload gripper enable detector:
     
     

   • Unload gripper HP and end position (EP) detector:
     
     

   • Unload roller HP and EP detector.
     
     

8. Detach the blue air tubes from the unload gripper piston:
   
   
   
   
9. From the front of the machine, remove the eight screws (four on each side) that secure the unload roller assembly base to the Optomec.
   Note: The unload gripper/roller assembly is mounted on pins.
10. From the rear of the machine, carefully lift the unload gripper/roller assembly off of the mounting pins and remove it from the machine.
11. Remove the unload gripper actuator from the base.
12. Turn the base over and remove the two side-to-side detectors from the base by removing the two small securing screws in each one.

Note: If FCO 27651 - Pressure/Vacuum Unit Assembly was implemented on your machine, make sure the air regulator valve is completely open before assembling the single-roller unload roller assembly.

Assembling the single-roller unload roller assembly

Note: The roller is not attached to the roller assembly when shipped. When unpacking the assembly, leave the protective paper on the roller until installation is complete.

1. On the side of the piston arm, release the locking screw and remove the lock pin from the underside of the roller bracket pin (shown below), and then lift the roller bracket pin out of the bracket.
   

2. Remove the piston arm from the assembly.
3. Insert the upper roller bushing on the shaft (as shown below) and attach it to the base of the assembly.
   

4. Replace the piston arm, insert the securing pin and tighten the locking screw (as shown in the picture below).
   

5. Attach the roller to the assembly base, as follows:
   1. On one side of the assembly base, remove the lock pin from the underside of the roller bracket pin (shown below), and lift the roller bracket pin out of the bracket.
      
   2. Push the bracket toward the outside of the assembly base, as shown below.
      
   3. Locate the two bushings and place one on each end of the roller as shown below.
      
   4. On the other side of the assembly base, place one end of the roller into the roller hole in the roller bracket.
   5. Push the bracket you moved in step 5b toward the center of the assembly until the roller is held firmly by both brackets.
   6. Replace the roller bracket pin and secure it in place using the lock pin you previously removed.
   7. Remove the Allan^® screw from one of the roller brackets (shown below), apply Loctite^® 242 to the screw and place it back into the bracket. Firmly tighten the screw. Repeat on the other side.
      
6. Secure the two side-to-side detectors you previously removed to the underside of the new assembly base, as shown below (one of two).
   Note: Be sure to apply Loctite^® to each screw.



7. Turn the assembly over and place the gripper assembly on the new, single-roller assembly. Verify that:
• The actuator is positioned properly on the new assembly—the unload gripper piston should be on the same side of the new assembly as the unload roller piston.
• The actuator is properly seated on the pins on both sides of the new assembly.
8. Secure the actuator to the assembly using the five screws previously removed.
   Note: Be sure to apply Loctite^® to each screw.

Installing the unload roller assembly

1. From the right, side door, locate the unload roller air valve (solenoid) in the manifold. If it does not have two air-tube nipples as shown below, replace the valve with the one included in the FCO kit.
   Note: Connect the blue air tube to the valve as shown below.



2. From the front of the machine, install the new unload roller piston by securing it to the two lowest securing holes on the Optomec, as shown in the pictures below (use the screws previously removed).
   Notes: The Optomec may have only two piston securing holes. If it does, secure the piston to these two holes (the same holes from which the piston was removed in step 6 in Removing and dissembling the currently installed unload roller assembly). Be sure to apply Loctite^® to each of the screws.



3. From the rear of the machine, place the new unload roller assembly on the Optomec and secure it in place using the eight screws previously removed.
   Notes: Make sure that the roller arm fits properly inside the piston. Be sure to apply Loctite^® to each screw.
4. From the front of the machine, connect the piston to the new assembly using the pin previously removed.
5. Connect the blue air tube that is included in the FCO kit, to the new air tube nipple on the unload roller air valve, as shown below.



6. Connect the two blue air tubes that are attached to the unload roller air valve to the unload roller piston (connect the old blue tube to the upper nipple, and the new tube to the lower nipple:
   
   
   
   
7. From the rear of the machine, reconnect the following connectors:
   Note: Be sure to secure all wires with plastic ties so that they will not touch any moving parts during machine operation.
   • Two side-to-side detectors.
   • Unload gripper enable detector
   • Unload gripper HP and EP detetctor.
   • Unload roller HP and EP detector.
8. Reattach the blue air tubes to the unload gripper piston.
   Note: Attach the tube labeled "in" to the innermost nipple, and the tube labeled "out" to the outermost nipple.
9. Remove the protective wrapping from the new roller, and clean the roller with a lint-free cloth.
10. Open the wall air pressure unit valve. Be sure that the air pressure level is between 6 and 8 bar.

Testing unload roller function

1. From the right side of the machine, manually activate and deactivate the unload roller air valve by pushing the red button on the valve. Verify that:
   • There is no air leakage from either end of the blue air tubes connected to the unload roller piston.
   • The roller is not pressed forcefully on the drum (while the roller is on the drum, gently lift it to verify that it only rests on the drum by virtue of its own weight).
2. Verify that the HP detector is functioning properly. If it is not, adjust it as required.
3. Manually turn the drum and position the tail gripper slots underneath the unload gripper pins.
4. From the right side of the machine, manually activate and deactivate the unload gripper air valve by pressing the red button on the valve. Verify that:
   • There is no air leakage from the blue air tubes connected to the unload gripper piston.
   • The unload gripper functions properly.

   
   Note: In the event the old type vibration sensors assembly is installed on your machine, you must readjust the vibration sensors due to the extra weight of the one piece roller.

   
   

5. Close all doors and start up the Lotem.
6. Verify side-to-side function, and adjust, as required.
7. Load, expose and process several plates of different sizes. Verify that there are no pressure marks, and that all is working properly.

Action required

Material disposition

Send the old base, valve and piston to the relevant DU. The old roller can be thrown away.

Logistics

Approved quantities:

Scheduled supplies for first lots:

Inventory in warehouses: N/A

Technical contact

Itai Peperovich

Date submitted

27 May 2002