Monday, May 14, 2012

Roller Clutch Service

Pictured below is a roller clutch from an HP LaserJet 4100's paper feed assembly.


Note the rollers in the bore that give the clutch its name.

Roller clutches all free-wheel in one direction of rotation, and grip the shaft they're on in the other direction. The clutch pictured was slipping badly in its grip direction. When I was trying it by hand with the assembly out of the printer, it would only grip intermittently; mostly it just free-wheeled in both directions.

These clutches are long lasting, but they will get gummy inside as they age, and that causes them not to grip. To restore a slipping clutch, soak it in Varsol for a few minutes to dissolve the gum, dry it thoroughly, then lubricate it with WD-40 on reassembly. Odds are good that the clutch will work fine. The one in the photograph responded nicely to that treatment.

Roller clutches are widely used, and none are immune to gumming and slipping. The result is invariably intermittent, baffling paper jams. It's a good practice to familiarize yourself with where the roller clutches, if any, are in any given machine.

# # #


# # #

1 comment:

  1. This comment has been removed by a blog administrator.

    ReplyDelete