• Discovery MR750w and SIGNA™ Architect T 3.0T System Service Methods
  • 5690002-2EN Revision 4
  • Object ID: 00000018WIA309D1130GYZ
  • Topic ID: id_15271094 Version: 3.4
  • Date: Feb 7, 2022 10:19:00 PM

Leveling the patient table

Adjust the patient table for floor levelness and do a check of the caster height. If adjustment is required, level the patient table.

Prerequisites

Personnel requirements
Required personsPreliminary requirementsProcedureFinalization
1-60 minutes5 minutes
Tools and test equipment
ItemQuantityEffectivityPart numberManufacturer
Non-ferrous Level1---
Non-ferrous measuring device (ruler)----
Non-magnetic Service Tool Kit1-

5112581

-
Safety

About this task

Overview

The patient table is aligned vertically to the magnet by adjusting the caster height. However, the caster height must also be checked for uniform loading to ensure levelness.

Topic ID: id_SL1961098-1057615

Adjusting the patient table for floor levelness

Procedure

  1. Dock the patient table.
    Note: If the dock mechanism is not properly adjusted (during installation), put the patient table in the approximate location it will be in when docked.
    • Be careful not to let the casters sit in a rut or seam on the floor.
    • Make sure that the table is positioned on a relatively level surface.
  2. Lock the rear caster brakes.
  3. Raise the patient table to a fully raised position. Using a nonferrous level, check levelness from front to back along the top right or left edge of the bridge, and from left to right across the front of the bridge.
    Figure 1. Measuring levelness of patient table
    Note: Check that all casters are sharing the load equally by applying a small lifting force at each corner of the table, and watching the caster lift easily off the floor. If one caster or two diagonally-mounted casters seem to be unevenly loaded compared to the other casters, they will require adjustment.
Topic ID: id_SL1961102-1057615

Checking caster height adjustment

About this task

During installation, this procedure describes how to check the caster height (factory default) settings. If the patient table requires adjustment, continue to Leveling the patient table.

Procedure

  1. To help keep track of measurement data, temporarily label each caster as 1, 2, 3, and 4. Based on the Caster Wheel Labels in Figure 1, label the steering caster as 1 (front left while facing the magnet), and proceed labeling in a clockwise direction.
  2. Remove the lower side covers (see Patient Table Upper Bellows and Lower Base Side Cover Removal) and front and rear caster assembly covers.
  3. At each of the four caster wheel assemblies, measure the height from the floor to the bottom edge of the aluminum support casting.
    Figure 2. Caster measurement
  4. Record the values for each caster in the table that follows.
    Note: In the table below, the Delta figure is the actual height measured minus the nominal shown in Figure 2. This provides a measurement by which to adjust the caster height.
    Caster measurement values
    Caster 1st Measurement 2nd Measurement
    Height Delta ± Height Delta ±
    1
    2
    3
    4
Topic ID: id_SL1961106-1057615

Leveling the patient table

About this task

Although all four casters look identical on the outside, there is one notable difference when observing each caster assembly inside the caster covers. The patient table front left caster is known as the steer lock wheel, and its caster assembly design has a triangle-shaped bracket that differs from the other three casters.

Procedure

  1. Undock the patient table and put it 1 to 2 inches in front of the dock to do work as close to the docked position as possible.
    Note: From the previous procedure, both caster assembly covers and the lower side covers are still removed.
  2. Disengage the rear caster brake lock pedal.
  3. For the caster that requires adjustment, remove the caster linkage pin using a 3/8 inch wrench.
    Figure 3. Caster linkage pin
  4. Remove the collar bolt using an 7/16 inch wrench. (The illustration below shows a floor-level view looking at the right underside of the caster assembly; the same view for all four casters.)
    Figure 4. Remove collar bolt
  5. Slide the collar down the shaft so it rests on top of the caster shaft housing.
  6. Looking from the top down, move the wheel lock lever to the Full Lock position.
    Figure 5. Wheel lock Lever positions

    The wheel lock lever has three positions:

    • Full Lock or Pivot Lock - Left position locks the caster so the patient table cannot move.
    • Free Swivel - Middle position lets the caster move freely.
    • Steer Lock - Right position locks the caster in place, but the wheels can turn.
  7. Turn the caster clockwise (raise the table) or counterclockwise (lower the table) to make adjustments.
    Note: Turning the caster one complete revolution raises or lowers the caster by 1.5 mm. Quarter or half turns on any caster are not possible because the collar must return to its home position.
  8. Measure the caster height again and record the value in Table 1.
  9. Do Step 3 through Step 6 in reverse order to reassemble the caster bolt and linkage pin.
  10. After all casters are adjusted, measure the table levelness, and adjust the casters as necessary by repeating this procedure.
  11. After the table is level, reattach the caster assembly covers, lower the side covers, and dock the patient table.
Topic ID: id_15379090

Finalization

Procedure

  1. Dock the table.
  2. Make sure that the cradle release functions properly.
  3. Make sure that the LPCA connects to the cradle and that the cradle can move into the bore.