Cadillac 60 Series 1963 Shop Manual page 331

12-50
ELECTRICAL SYSTEM
Relay Armature Ground Strap
Relay Coil
Stop Arm
High Speed Resistor
Terminal Board
Latch Spring
Latch Arm
Drive Plate
Drive Pawl
Drive Pawl Spring
Nylon Gear
Fig. 12-73 Windshield Wiper Drive Mechanism - 60 and 62 Series
This, with the aid of the large drive pawl coil
spring, pulls the drive pawl clear of the stop arm
and the entire drive gear assembly then rotates
as a unit, resulting in normal wiper operation.
Sliding the switch lever to the "Off" position
opens the relay circuit and allows the spring
loaded latch arm to move into position to intercept
the drive pawl. When the drive pawl is in contact
with the latch arm, the wiper arms and blades are
approaching parked position and the motor con-
tinues to drive the nylon gear and the eccentric
shaft for approximately 180°. During this rotation,
the cam action between the eccentric shaft and the
drive plate moves the drive pawl along the contour
of the latch assembly to open the motor circuit at
the relay control switch as the blades arrive at
the park position.
Washer Circuit
Depressing the washer button on the control
switch mechanically moves the switch lever to the
"Lo" speed position. The washer relay coil is
energized by the current flowing from the No. 2
terminal on the wiper unit connector through the
brown wire into the relay coil and from there
through the orange wire to ground in the control
switch.
Mechanical Washer Operation
The washer is driven by a pin that is attached
to the nylon gear in the wiper assembly. This pin
fits into the washer rotor cam and drives the
pump, at idle, whenever the wiper is in operation.
When the washer button is depressed, the
washer circuit is completed to ground and the
washer relay is energized, pulling the relay ar-
mature and ratchet pawl away from the nylon
ratchet wheel, Fig. 12-75. At this point, the wire
stop slips into position and holds the relay arma-
ture away from the ratchet wheel, allowing the
ratchet pawl, which was previously moving back
and forth through the armature opening, to drop
out of the opening and start to rotate the ratchet
wheel.