Rev.B
Overview of the Mechanisms Appendix B-3
TM-L90 Service Manual
Confidential
Print/Paper Feed Unit
The print/paper feed unit consists of various frames, thermal print head, head holder
mechanism, paper feed motor, reduction gear, and cover open detector.
The right and the left frames supporting the thermal print head can be installed or removed
together with the paper supply unit, and provide the locator for the paper feed roller shaft
holder.
The circuit board frame holds the main circuit board that controls the printer mechanism.
The cover open detector detects if the cover unit is closed or open.
Rotating the paper feed motor when the cover unit is closed drives the reduction gear to rotate
the platen. Thermal paper is fed, if it is rolled up on the platen.
With the thermal paper pinched between the platen and the thermal print head, the printing is
performed by heat generation in the heating element of the thermal print head.
Thermal print head
Head holder mechanism
Platen shaft holder locator
Cover open detector
Frame R
Frame L assembly
Reduction gears
Paper feed motor
Circuit board frame