Providing A Force On Top Of The Media; Bail; Bail Lift Mechanics; Bail Sensor - HP DesignJet 200 Service Manual

Providing a Force on Top of the Media

Bail

The bail provides a normal force on top of the media. (Illustration ' page 10 25.) When the
pinch wheels grip the media and the drive roller advances it, the plotter raises the bail. This
enables the leading edge of the media to pass below the bail. The plotter then lowers the bail
and advances the media to the overdrive roller. The star wheels on the bail are coated with a
substance resistant to wet ink, so that they do not leave marks on the media.
Bail Lift Mechanism
The bail features an automatic lift mechanism driven by the media motor using a series of
gears and actuated by the cartridge carriage.
Operation
(Part illustrations ' page 10 25)
1 The cartridge carriage presses down on the engaging lever.
2 The engaging lever gear and cam gear (which are always in contact) engage the
drive roller gear on the left end of the drive roller.
3 The media drive system drives the drive roller, and also the cam and engaging lever
gears. The auto cam, which is attached to the cam gear, turns with the gear.
4 The auto cam contacts the left bail bracket and pushes up on the bracket. As the bracket
is pushed, the bail lifts.
5 The bail sensor switch opens and the resulting bail logic level is sent to the main PCA.
6 The media drive rotates the auto cam to a detent position. The detent position allows the
bail bracket to rest on the auto cam after the carriage moves away from the engaging
lever.
7 The media drive drives the media through the media path.
8 Once the media has passed the bail, the carriage again engages the bail lift mechanism to
lower the bail.

Bail Sensor

The bail sensor informs the processor of the bail position (Up or Down). It is a mechanical
microswitch located on the right side plate. (Illustration ' page 10 25)
5 8 Functional Overview
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