in turn is controlled by the controller board. The following is a list of actuators: • Door solenoid – locks the door to the modeling chamber. • Carrier latches – holds carriers in the material bays. • Material bay solenoids – engage the motor that feeds filament from carrier to the liquefier during auto load. The controller board reads and updates the remaining material information on the spool e-prom. This is accomplished through a serial interface to the material bay encryption board. The material encryption board in turn connects to the e-prom on the carrier/spool via two pogo pins. The controller board monitors these switches:
• Z limit switches – upper and lower • X end of travel (EOT) switch • Y end of travel (ETO) switch The controller board monitors the following optical sensors: • X home (BOT) sensor • Y home (BOT) sensor • Top of modeling base sensor Safety Devices The controller board monitors the following safety devices: • Chamber T/C alarm – activated for a bad or missing T/C • Liquefier T/C alarm – activated for a bad or missing T/C • Head and chamber “snap” switches • Two main thermal fuses • Door open switch • Door latch solenoid Controller Board Layout (Figure 4) Shows the layout of the controller board connectors with labels indicating where each of the functions described previously are connected.
In addition to those functions, the figure shows a reset button, a set of dip switches, and the LEDs (D1-D3 and D6-D13). -10