Steering Pump - Honda Civic 1998 Service Manual

Steering Pump
Construction
The pump is a vane-type incorporating a flow control valve (with an integrated relief valve) and is driven by a POLY-V-belt
from the crank pulley, The pump features 10 vanes. Each vane performs two intake/discharge operations for every rota-
tion of the rotor. This means that the hydraulic fluid pressure pulse becomes extremely small during discharge.
ROTOR VANE CAM RING
Operation
The belt,driven pulley rotates the rotor through the drive shaft. As the rotor rotates, the hydraulic pressure is applied to
the vane chamber of the rotor and the vanes will rotate while being pushed onto the inner circumference of the cam ring.
The inner circumference of the cam ring has an extended portion with respect to the center of the shaft, so the vanes
move downward in the axial direction as the rotor rotates. As a result of this roller movement. the internal volume of the
v a n e c h a m b e r w i l l c h a n g e , r e s u l t i n g i n f l u i d i n t a k e a n d d i s c h a r g e .
START OF FLUID INTAKE:
FLUID INTAKE:
FLUID MOVEMENT:
FLUID OISCHARGE:
T h e v a n e s a r e p u s h e d o n t o
the inner circumference of the
c a m r i n g .
The volume of the vane cham
ber increases so that fluid is
sucked in.
T h e s u c k e d - i n f l u i d m o v e s
toward the dascharge pon.
A s t h e v a n e s r e t u r n t o t h e
t h e i r o r i g i n a l p o s i t i o n o n t h e
inner side, the volume of the
v a n e c h a m b e r d e c r e a s e s s o
t h e f l u i d i s d i s c h a r g e d f r o m
the discharge port.
(cont'd)
1 7- 17
FLOW CONTROL VALVE