EPSON Stylus CX3500/CX3600/CX3650/CX4500/CX4600 Revision A
OPERATING PRINCIPLES Printer Mechanism 63
2.2.5  Ink System Mechanism
The Ink System Mechanism consists of Pump mechanism with Carriage lock 
mechanism and Capping mechanism with Wiper mechanism. Following table lists the 
function for each mechanism.
Note : Like the previous printers (Stylus Photo R300/R310), this printer adopts the valveless 
cap system. The air valve system used for the previous printer (Stylus COLOR 740) 
have two functions by the CR position in the capping condition as follows.
1) Valve closing condition (CL position)
By closing the air valve, the ink is forcibly absorbed from the Ink Cartridge 
or the ink cavity by the Pump Unit and is ejected to the Waste Ink Pad while 
the Carriage Unit is in the CL position.
2) Valve opening condition (Ink absorption position)
By opening the Air valve, the negative pressure is decreased and only the 
ink inside the Cap is ejected while the Carriage Unit is in the further right 
side than the CL position. (the ink is not absorbed from the Ink Cartridge or 
the ink cavity.)
The following shows you the Carriage Unit position for each condition easily.
But, on the valveless cap system, the above 2) operation is done outside the 
capping position. The Carriage Unit moves outside the CR home position and 
the pump absorbs the ink inside the Cap.
Table 2-4.  Function for each mechanism
Mechanism Function
Capping mechanism *
This is to cover the surface of the Print Head with the cap in 
order to 
prevent the nozzle from increasing viscosity.
Wiper mechanism
This is to remove the foreign material and unnecessary ink on 
the nozzle plate of the Print Head.
Pump mechanism
This is to eject the ink from the Ink Cartridge, the ink cavity and 
the cap to the Waste Ink Pad.
Carriage lock mechanism 
This is to lock the Carriage Unit with the Change Lever while 
the Carriage Unit is at the home position. 
CL position
(valve closing condition)
Printing area CR home position
Ink absorption position
(valve opening condition)