Space Mechanism / Operation - Oki ML390 Service Manual

Page: 27
Service Guide ML390/391
Chapter 2 Principles of Operation

2.4.02 Space Mechanism / Operation

The spacing operation is performed by applying power to the DC spacing motor. This drives the carriage
frame along the carriage shaft, space rack, and guide rail. The carriage shaft, space rack, and guide rail
are parallel to the platen.
The spacing motor assembly consists of the following items.
· DC Motor / Gear
· Carriage Frame
· Carriage Shaft
· Space Rack
· Encoder Disk Sensor
· Encoder Disk
· Guide Rail
Spacing Operation
The printhead and spacing motor are mounted on the carriage frame. The carriage frame moves along the
carriage shaft, space rack, and guide rail. The carriage shaft, space rack, and guide rail are parallel to the
platen. As the spacing motor rotates counterclockwise, the carriage frame is driven to the right.
When the spacing motor rotates one turn, the carriage frame moves 0.8 inch (20.32 mm).
Motor rotation turns the encoder disk. The timing windows on the disk then pass through the encoder disk
sensor. The position of the carriage frame is obtained by counting the pulses generated by the encoder
disk sensor as the disk turns.