Ricoh BR-C1a Basic Service Training page 234

 As lubricant [A] is consumed gradually, the tab [B] in the
lubricant holder shifts in the direction "C".
 When lubricant decreases to a certain amount, the tab [B]
touches the feeler [D].
Slide 234
Copied from CH-C1
Lubricant Near-end Detection
Operation - 1
234
BR-C1 Training