Bendix Commercial Vehicle Systems COMPACT 500 9/87 - Manual

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COMPACT 500 INTEGRAL HYDRAULIC POWER STEERING GEAR
FOR FORD MOTOR CO. CARGO VEHICLES
SD-30-4250
I. DESCRIPTION
The Compact 500 Hydraulic Power Steering gear is designed
for heavy duty vehicles with front axle weight ratings of up to
15,000 lbs. It is an integral power steering gear incorporating
the mechanical and hydraulic actuation and control
components in a single cast housing which serves as the
power cylinder.
The vehicle’s steering column is coupled to the gear at the
input shaft which transmits steering effort through a
recirculating ball screw and piston nut. The piston nut is an
integral part of the power assist piston and also acts as a
steering damper. The direction and degree of power assist
is controlled by a rotary hydraulic valve which is integral to
the input shaft and supplied by an engine driven hydraulic
pump.
This valve design assures light, responsive steering while
maintaining a mechanical connection between the steering
column and the ball screw.
II. OPERATION
GENERAL
The C-500 integral power steering gear is composed both of
mechanical steering components and hydraulic power assist
components. Actual steering is accomplished mechanically.
Effort applied at the vehicle’s steering wheel results in
mechanical movement within the steering gear which causes
the vehicle to change its direction of travel. The hydraulic
power assist components function solely to reduce the effort
required to turn the vehicle’s steering wheel. Loss of hydraulic
power will in no way prevent the vehicle from being
maneuvered mechanically, however greater effort will be
required to turn the steering wheel.
MECHANICAL OPERATION
The turning effort exerted by the driver on the steering wheel
is transmitted to the input shaft which is part of the ball
screw assembly. The ball screw and piston nut function like