Epson 7000 service manual Description of Components, Carriage Movement

EPSON Stylus Pro 7000 Revision B

2.2 Description of Components

2.2.1 Carriage Movement

To print on paper as wide as A1+ (24 inches), the carriage must be quite stable and must travel further than the usual carriage. To increase stability, the SP 7000 uses a carriage guide rail instead of the carriage guide shaft. The carriage comes into direct contact with the printer frame using a set of bearings which are attached to the carriage.

The CR motor (DC motor) drives the carriage, and the Linear Encoder sensor in combination with the T-Fence (plastic timing fence found underneath the carriage guide rail) determine the lateral position of the carriage. As shown in Figure 2-7 below, the Linear Encoder reads the timing stripes to determine the position of the carriage as well as the carriage speed, and this data is sent to the software servo.

NOTE: CR motor errors (such as overcurrent) and encoder sensor malfunctions can be caused by simple problems; for example dust/ink on the T-Fence or the T-Fence is out of the sensor.

Carriage

Linear

Encoder

Carriage

flag

T-Fence

Home Position

Sensor

The following sensors are used in combination with the carriage components:

†Home Position Sensor

This optical sensor activates when the CR Guide Rail flag enters the space between the light emitter and the light receiver. The flag is located on the carriage and the sensor is located to the right of the maintenance assembly. The HP sensor sends an “On” signal when the carriage is in the home position.

†Linear Encoder sensor

This sensor is located on the back of the carriage (cutter housing section). This reflective photo sensor helps determine the exact carriage location by counting the clear and dark sections of the T- Fence. The Linear Encoder sends a pulse to the printer logic as a PTS (Print Timing Signal). The shaded sections have a distance equal to 180 dpi.

Carriage

Figure 2-7. Carriage Mechanism & CR Guide Rail

Operating Principles Description of Components 60