Model 5200 High-Level Orderpicker
Section 8. Theory of Operation Steering
Steering
CHB). The relationship between these two square waves tells the CM what way the steering wheel is turning. The number of pulses generated tells it how far and how fast the steering wheel has been turned. The degree of rotation of the drive unit is not in direct correlation to the distance the steering wheel is turned. When the steering wheel stops turning, the drive unit stops turning. Determining what way the steering wheel is turned is based on the one of the two square waves that is ahead of the other. The one that is ahead tells what way the wheel is turning. See Figure 8-1.
The Steering Encoder is installed on the operator’s carriage, behind the steering wheel. When the battery is connected, the key switch is ON, and the deadman pedal is down, the following events occur when the operator turns the steering wheel in either direction: •
The steering encoder sends a quadrature-phase output to the CM when the steering wheel is turned. As the steering wheel is turned, two individual square waves are produced (CHA and Ø LEFT TURN
CHANNEL A leads CHANNEL B by angle Ø
CHANNEL A
CHANNEL B
Ø
RIGHT TURN
CHANNEL A lags CHANNEL B by angle Ø
CHANNEL A
CHANNEL B Figure 8-1.
Steer Position Encoder Output
Publication Number: 1043922B, Revised: 2 Sept 2015
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