Canon iPF750 series, Service Manual

Page: 110 / 328

Chapter 2
2-20
2.3.2.3 Carriage Unit
2.3.2.3.1 Functions of Carriage Unit
0023-1473
iPF765 / iPF760 / iPF750 / iPF755
a) Printhead mounting function
The carriage mechanically locks the printhead and transmits the print signals to the printhead via the carriage PCB.
b) Control function
The carriage incorporates a carriage PCB that relays the signal from the main controller, a linear encoder that generates a print timing signal based on the detected
carriage position, and a multi sensor that detects the media width and skewing to adjust the registration and height.
The carriage PCB and main controller PCB are connected with a flexible cable.
c) Carriage drive function
The carriage motor moves the carriage back and forth on the platen via the carriage belt.
d) Printhead maintenance function
The printer performs the printhead cleaning operation such as printhead wiping and suction at the home position of the carriage.
e) Nozzle check function
The printer detects a non-discharging nozzle using the head management sensor attached to the maintenance jet tray by discharging ink with the carriage stopped
at the maintenance jet tray.
f) Media thickness adjustment function
If the gap between the printhead face and the media increases due to the difference in media thickness, cockling, curling, and so on, more ink mist is generated. In
reverse, if the gap decreases, the head can touch the media surface more frequently.
To maintain the proper gap, the remote lifter is driven to adjust the head height automatically according to the selected media type, media supply method, printing
conditions (borderless/priority print type), environmental conditions (temperature/humidity), and the result of measurement by the multi sensor.
The relationship between media types and head heights (from the platen) is summarized in the table below. Note that the head height is adjusted with priority given
to the media gap measured by the multi sensor.
*1: Roll media, borderless printing, standard mode excert for line document
g) Paper leading edge detection function/paper width detection function/skewing detection function
The leading edge, width, and skewing of the paper fed to the platen is detected by the multi sensor mounted at the lower left of the carriage.
h) Auto printing position adjustment function
The adjustment pattern printed on paper is read by the multi sensor mounted at the lower left of the carriage, thus adjusting the printing timings of each printhead
automatically.
i) Remaining roll media detection function
The amount of the remaining roll paper can be detected using the multi sensor mounted at the lower left of the carriage by printing a barcode at delivery of the roll
media.
j) Internal temperature detection function
The internal temperature around the printhead is detected using the thermistor mounted on the carriage PCB.
Head height (mm) Media type (Value in parentheses:mm)*1
1.0 (select by the user when using the plain paper)
1.3 Photo paper, Synthetic paper, Backlit film
1.8 Plain paper, Coated paper
2 Heavyweight coated paper
2.2 Premiun matte paper, Special
2.6 Special (at the low humidity or high humidity)