SLIA097 March   2022 DRV5011 , DRV5011 , DRV5012 , DRV5012 , DRV5013 , DRV5013 , DRV5015 , DRV5015 , DRV5021 , DRV5021 , DRV5023 , DRV5023 , DRV5032 , DRV5032 , DRV5033 , DRV5033 , TMAG5110 , TMAG5110 , TMAG5111 , TMAG5111 , TMAG5123 , TMAG5123 , TMAG5231 , TMAG5231 , TMAG5328 , TMAG5328

 

  1.   Trademarks
  2. 1Introduction
  3. 2Flow Meter Design
    1. 2.1 Mechanical Considerations
    2. 2.2 Magnetic Considerations
      1. 2.2.1 Material
      2. 2.2.2 Geometry
      3. 2.2.3 Magnetic Deign Tools
    3. 2.3 Hall-Effect Sensor Considerations
      1. 2.3.1 Device Sensitivity
      2. 2.3.2 Unipolar Switch
      3. 2.3.3 Omnipolar Switch
      4. 2.3.4 1D Latch
      5. 2.3.5 2D Integrated Latch
      6. 2.3.6 Bandwidth
      7. 2.3.7 Package
      8. 2.3.8 Power Consumption
  4. 3Flow Meter Development
    1. 3.1 3D-Print Recommendations
    2. 3.2 Flow Meter Assembly Considerations
    3. 3.3 Flow Meter Assembly Guide
      1. 3.3.1 Shaft Installation
      2. 3.3.2 Bearing Installation
      3. 3.3.3 Magnet Installation
      4. 3.3.4 Impeller Installation
      5. 3.3.5 O-ring Installation
      6. 3.3.6 Flow Meter Top Installation
      7. 3.3.7 PCB Mounting
      8. 3.3.8 Cover Installation
  5. 4Flow Meter Evaluation
    1. 4.1 Flow Meter Testing
  6. 5Error Sources
    1. 5.1 Mechanical Error
    2. 5.2 Sampling Error
    3. 5.3 Magnetic Error
  7. 6Flow Meter PCB
    1. 6.1 PCB Schematic
    2. 6.2 PCB Layout
  8. 7Bill of Materials (BOM)
  9. 8References

3.3.2 Bearing Installation

Next, assemble the mechanical components into the flow meter impeller. Assembly of magnets varies depending on the selected variant of the flow meter, but the bearings must be pressed into the plastic housing in all three variants. Two 4- ×10- × 4-mm bearings are pressed into the inside of the impeller with the first bearing seating against the backside of the impeller housing. The next bearing is positioned against the backside of the previous bearing. The location of these two bearings dictates the height of the impeller, and how true the impeller rotates in relation to the shaft. Figure 3-2 shows a correctly assembled impeller.

Figure 3-2 Bearing Installation