Olivetti CMS 140 B euro, Service Manual

Page: 14 / 55

2-6 Service Manual 686770R
Paper feeding gear series
(See Fig. 2-2 and 2-5)
As shown in Fig. 2-5, the paper feeding gear series
consists of the paper feed ratchet wheel, paper feed
ratchet, paper feed drive gear assembly, paper feed
transmission gear, and paper feed gear.
During column selection or consecutive paper feeding,
the select mechanism and printing gear series operate
by extending the trigger coil drive signal at the first
column during space selection. However, the return
lever and trigger lever are unlocked (18) to maintain the
operation of the trigger plate and trigger lever. When the
print changeover cam rotates, the cam controlling the
return lever reaches a notched section. The return
lever is thereby released and beings operating (19) due
to spring force, and its interlocking with the paper feed
ratchet is cancelled (20).
The paper feed ratchet on the paper feed drive gear
assembly operates (21) due to spring force and
meshes with the teeth of the paper feed ratchet wheel
on the same shaft as the selective gear.
When printing operation is completed, the print
changeover cam causes the selective pawl to return to
its pre-selection status, and the print changeover cam
is stopped. When the selection gear begins rotation,
the paper feed drive gear assembly (22), paper feed
transmission gear (23), and paper feed gear (24) all
rotate together with the paper feed ratchet wheel. This
movement is then transmitted to the paper feeding
mechanism.
Fig. 2-5 Paper Feeding Gear Series