TM 5-3810-300-24 & P2
larger and can overcome area of front side of piston. The removal or application of air on backside of piston is controlled
by the insert valve in cylinder cover; this valve in turn is con-trolled by the range control valve.
The insert valve located in the shift cylinder cover is a small 1-3/16" Humphrey valve. It is installed with the flat surface
to the inside towards the center port, and it is secured with a special nut in bottom bore of cover.
The insert valve is self-contained and can not be disassembled except for the three O-rings on outer diameter. These
three O-rings are a stationary seal and do not move in cylinder.
Travel of the small piston in the insert valve is only 3/16". The insert valve is a normally-open valve. Thus, when there is
no signal or delivery of air to top side of insert piston, the constant air from regulator passes through the insert valve and
to the backside of the piston and moves the shift bar forward (low range).
When the insert valve piston is activated by a signal or delivery of air, the insert valve is closed and shuts off the
constant air to backside of shift piston. Air in shift cylinder is exhausted out through insert valve and bottom bore of
cover.
When air is removed from backside of shift piston, constant air on front side of shift piston moves the shift bar to the rear
(intermediate and direct range). Clutch and Actuating System. (Illus. 4-10).
Actuating System.
The operation of the Lipe Direct Pressure clutch (DLB) is as follows: The clutch flywheel ring (cover) is attached to the
engine flywheel and drives the pressure plate by means of driving lugs in the flywheel ring (cover) and mating slots in the
pressure plate.
Depressing the clutch pedal disengages the clutch, by allowing the release bearing to contact and move the release
levers toward the engine flywheel resulting in the pressure springs being compressed and the pressure plate being
retracted away from the disc assembly; thereby disengaging the clutch.
Releasing the clutch pedal engages the clutch by allowing the release bearing and release levers to move away from the
engine flywheel and the pressure springs to expand and exert pressure against the pressure plate, resulting in the disc
assembly being gripped between friction surfaces of engine flywheel and pressure plate; thereby completely engaging
the clutch.
Clutch.
The Lipe type (direct pressure) clutches are precision built heavy duty units incorporating few parts. These clutch
assemblies require no maintenance other than maintaining release bearing clearance which is accomplished by normal
linkage adjustment.
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