Canon BJC 6000 Service Manual - Page 105

BJC-6000 Part 4: Technical Reference 3.5.2 Construction of the carriage unit Carriage Ribbon Cable BJ Cartridge Mount Home Position Edge Carriage Lock Position Edge Signal Contacts Carriage Belt Carriage Motor Figure 4-26 Carriage Unit a) BJ cartridge mount BJ cartridges are secured to the carriage with the BJ cartridge lock lever. When a BJ cartridge is secured in place to the carriage, the carriage board signal contact pad contacts the BJ cartridge signal contacts, allowing print signals to be transmitted from the control board. The home position edge is provided to interrupt the light from the home position sensor on the chassis. b) Carriage drive unit Mechanical variances between the left and right BJ cartridges in vertical/horizontal and bi-directional printing can be corrected automatically or manually by adjusting printing timing. The carriage motor is a stepping motor that drives the carriage via the carriage belt to travel along the horizontal width of the paper. The carriage will be unlocked when the carriage lock position is detected by the home position sensor (photointerruptor type) located on the rear of the carriage. The carriage is controlled and driven by the stepping pulses fed to the carriage motor once the home position edge is detected as the reference for subsequent position control. The carriage motor is driven by the steady current generated by the motor driver, reducing drive loss and operating noise. 4-33