Epson 7000 service manual PAPER-FEEDING-RELATED Sensors, Paper Thickness Detection

EPSON Stylus Pro 7000 Revision B

PAPER-FEEDING-RELATED SENSORS

The following sensors aid in the paper feeding process.

† P_FRONT sensor

This sensor is attached to the subplaten and is an optical (photo-

reflective) sensor. This sensor detects the front edge of the paper after

paper has been loaded but before it is set and ready to print.

† P_REAR sensor

This sensor is attached to the Upper Paper Guide and is an optical

(photo-reflective) sensor. This sensor detects the rear edge of the

Note that the P-Thick and Paper Set Lever sensors as well as their corresponding flags are located next to each other. The sensors employ the two metal flags on top of the Secondary Roller unit (second from the HP side when facing the printer). The left flag is used to determine the paper thickness and the right flag is used to determine the Paper Release Lever position.

paper and detects the front edge when the paper is first loaded in the

paper path. The position of this sensor is stored in EEPROM.

† P_EDGE sensor

This sensor is attached to the Cutter Housing section on the carriage

and detects the right and left edges of the paper. This sensor is also

used to check for paper skew by checking whether the edges are in

the same location at the top and bottom of a page.

† P_THICK sensor

This optical sensor physically gauges whether the paper falls into the

normal/thin category or the thick category. For details, see “Platen

Gap Mechanism” on page 70.

Table 2-2. Paper Thickness Detection

Detected	Sensor Signal	Output Signal
Thickness		Strength
0.6mm or less	On	0.7V or more
0.7mm or more	Off	2.4V or more

†Paper Set Lever sensor

The Paper Set Lever sensor is located on the right side of the printer, and this optical sensor determines whether or not the Paper Set lever is in the set (print) position.

Double sensor and flag set: R = Paper set lever sensor L = P_Thick sensor

Paper feed

direction

P_Rear sensor

Paper Set

lever

P_Front sensor

Figure 2-12. Paper Feed Sensors

Operating Principles Description of Components 64