QMDI delivery chain snapped

[mightyandy]

Hi Guys,

One of the chains snapped in on our QMDI classic. The press was quickly emergency stopped however by this time it had already bent & snapped gripper bars.

On inspection there appeared to be no damage done to cylinders etc.. So we purchased a replacement set off a press broke for parts. We climbed inside delivery side with a flash light and got the replacement chains hooked over the sprocket at tooth over the hole for timing.

Now for our new problem, The press can be inched over, inches while feeding paper, run without feeding sheets but when you press to feed sheets while the press is turning over it halts immediately and brings up a "Late Sheet" error while the initial sheet is fed into the press.

What would cause this problem, has a sensor got knocked or the presses timing been altered when the gripper bars smashed?

[video]https://www.youtube.com/watch?v=KWOKsN-8igc[/video]

[video]https://www.youtube.com/watch?v=UwDpu3YwGvk[/video]

Any thoughts would be appreciated

 

[mightyandy]

** UPDATE **

We put some cylinder bar stock through the sidewall into the cylinder to find mechanical zero and checked the degrees according to the encoder (IDS) read at 000.5 degrees so this seemed to be about right.

We then inched the press over with feed enabled and the sheet was first detected at 323.5 Degrees according to channel 062 (VD).

 

[mightyandy]

Some more information

Also we done an emergency stop during the imaging process while the clutch was disengaged

 

[mightyandy]

Update in case this helps anyone else.

When our chain delivery got smashed the helical gear beside the sprocket within the chain delivery moved on the adjusters.

The encoder is attached to the end of this shaft so when the gear moved this changed the value on the encoder and the press now thought paper was being fed to late.

To resolve this problem we removed the encoder & bearing. Adjusted the gear wheel so the grippers were in the correct timing to receive the paper from the cylinder grippers. We then replaced the bearing, found the mechanical zero aligning the hole within the cylinder and the side of the press Then we refitted and zeroed the encoder.

 

[Linus]

I also have a similar problem . I am about to remove the encode. Please tell me details how to "mechanical zero aligning the hole within the cylinder and the side of the press" and "zeroed the encoder"
Thanks

 

[jan]

Don't need to remove encoder. First put the pin in the frame and cylinder to find how many degrees it is moved.
You have to loose 3 screws on the sprocked wheel (every 120 degrees each one, you will have to inch press to reach next screw).
Now you can set the encoder on the right position pulling/pushing the delivery bridge. It'll move few degrees towards and back.