• Topic ID: id_11038866
  • Version: 3.0
  • Date: Apr 9, 2020 8:50:12 PM

Inspect Bowtie Filter

Prerequisites

It is possible that the Bowtie Filter is contaminated and the Primary Copper Filter is not contaminated.

note:

Perform this inspection before installing the new tube unit. Also look at the tube side of the copper filter when you are swapping the interposer plate. Remove any debris found before installing the interposer plate on the new tube unit.

Procedure

  1. Remove the Collimator Control Board Sheet Metal Cover. See Figure 1

    Figure 1. Collimator Control Board Cover

    2. Notice Image
    • notice
    • Do Not Attempt to Move the Filter with Power ON.
    Notice Image
    • notice
    • Do not force the filter if it feels stuck. Damage to the limit switch can result.
    Notice Image
    • notice
    • Do not move the filter more than necessary for inspection. The filter can fall off the drive screw.
  2. With power removed from the gantry, turn the position adjuster to position the bowtie filter assembly so it is visible through the input port or tube side of the collimator assembly.

    • CCW will move the filter into the beam. See Figure 2.

    • Do not move the filter back to the home position.

    Figure 2. Filter Position Adjuster

  3. Using a flashlight, inspect the bowtie filter for contamination. Reference Figure 3.

    Look through the input port or tube side of the collimator.

    If contamination is visible, proceed to: Collimator Cleaning Procedure

    Figure 3. Contaminated Bowtie Filter

Finalization

No finalization steps.