| 摘要 |
A moisture system control apparatus is provided for metering the rate of feed of dampening fluid from a fountain apparatus including a fountain roller to a master on a master cylinder of a lithographic duplicating machine. The control apparatus comprises a linkage for converting continuous rotary input motion to incremental rotation of the fountain roller, and infinitely variable selector apparatus for adjusting the magnitude of the rotation increments employed during a first mode of operation which obtains while printing is in progress. Trip apparatus is provided for establishing a second mode of operation, in response to non-feeding of a copy sheet, in which the magnitude of the incremental rotations of the fountain roller are reduced from that obtaining during the first mode of operation to maintain the rate of feed of the dampening fluid at a low level while the machine is idling and copy sheets are not being duplicated, and for restoring the operation of the fountain roller from the second mode of operation to the first in response to a copy sheet being fed and the printing operation resumed.
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