Vacuum Pump Asymmetric Inlet Geometry for Compact Installation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional vacuum pumps require significant installation space due to the circular geometry of their ports, limiting the proximity of inlet openings and increasing the overall size of the pump.

Innovation Solution

The vacuum pump design incorporates a circular first inlet opening and a rectangular or square second inlet opening, arranged coaxially with a common pump shaft, allowing for closer placement and reducing transverse space requirements, along with a bleed channel connecting the openings to manage pressure levels and minimize turbulence.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If circular geometry is used for both inlet openings, then sealing and structural simplicity are improved, but installation space requirement increases

Engineering Contradiction:
Improvesealing simplicityVSAvoidinstallation space
Core Design Contradiction:
Ease of manufactureVSArea of stationary object

Solution Approach 1:

The patent applies asymmetry by using different geometric shapes for the two inlet openings: the first inlet opening (for the first pumping stage) has a circular shape, while the second inlet opening (for the second pumping stage) has a rectangular or square shape. This asymmetric design allows the rectangular opening to be positioned closer to the circular opening, reducing the overall installation space requirement while maintaining adequate sealing for each port type.

Inventive Principle:
Principle #4Asymmetry

2Area of stationary object

If ports are positioned close together, then installation space is reduced, but minimum cross-sectional area requirements cannot be met

Engineering Contradiction:
Improveinstallation spaceVSAvoidcross-sectional area requirement
Core Design Contradiction:
Area of stationary objectVSManufacturing precision

Solution Approach 1:

The patent applies local quality by optimizing the geometric shape of each inlet opening according to its specific functional requirements. The circular first inlet opening is optimized for the first pumping stage's sealing needs, while the rectangular second inlet opening is optimized for compact positioning. Each opening maintains its required cross-sectional area locally, while the overall arrangement achieves compact installation space through the rectangular configuration of the second opening.

Inventive Principle:
Principle #3Local quality

3Adaptability or versatility

If geometric changes occur in dispensing channel, then connection flexibility is improved, but turbulence increases

Engineering Contradiction:
Improveconnection flexibilityVSAvoidturbulence
Core Design Contradiction:
Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The patent applies inversion by maintaining geometric consistency rather than introducing changes. The cross-sectional geometry of the dispensing channel is kept substantially uniform along its length, matching the rectangular shape of the second inlet opening. This inverted approach (avoiding geometric changes) minimizes turbulence in the gas flow while still providing adequate connection flexibility through the rectangular configuration's inherent adaptability.

Inventive Principle:
Principle #13The other way round (Inversion)

Data Source

PatentEP3296571B1Vacuum pump
Publication Date: 2021.11.03 PFEIFFER VACUUM GMBH
  • EP3296571B1 patent drawingFigure 1~2
  • EP3296571B1 patent drawingFigure 3~5

AI summary

The present invention relates to a vacuum pump, in particular a turbomolecular pump, comprising at least one first pumping stage with at least one first rotor and at least one second pumping stage with at least one second rotor, the axis of rotation of which is arranged, in particular, coaxially with that of the first rotor. A first inlet opening, substantially circular and associated with the first pumping stage, and a second inlet opening associated with the second pumping stage are provided. The second inlet opening has a substantially rectangular or square shape. The first and second inlet openings are arranged on an axial end face of the vacuum pump. The second inlet opening is connected via a dispensing channel to a dispensing port located between the first and second pumping stages.