Vacuum Pump Sealing Element Radial Axial Gap Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing rotary pumps, particularly vacuum pumps for motor vehicles, face challenges in effectively sealing the delivery chamber to prevent fluid leakage, especially due to manufacturing tolerances and the design of sealing gaps.

Innovation Solution

The rotary pump incorporates a sealing element that forms both radial and axial gaps with the housing part, where the axial gap is larger than the radial sealing gap, and is connected to the drive shaft and conveying element carrier in a materially bonded or form-fitting manner to ensure secure sealing without axial or radial guidance, compensating for manufacturing tolerances.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a radial sealing gap is formed between the sealing element and housing part, then fluid leakage is reduced, but manufacturing tolerances make effective sealing difficult

Engineering Contradiction:
Improvesealing effectivenessVSAvoidsealing gap tolerance
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent introduces an axial gap dimension in addition to the radial sealing gap. The sealing element forms both a radial sealing gap (for primary sealing) and an axial gap (larger than radial gap) with the housing part. This dimensional addition allows the sealing mechanism to compensate for manufacturing tolerances by utilizing the axial direction as a compensation zone, thereby maintaining effective sealing despite variations in radial gap dimensions.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent specifies that the axial gap should be larger than the radial sealing gap. This parameter relationship creates a sealing configuration where the larger axial gap provides tolerance compensation space, while the smaller radial gap maintains effective sealing. By establishing this specific parameter relationship, the design accommodates manufacturing variations without compromising sealing reliability.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the sealing element is connected to the drive shaft and conveying element carrier, then sealing stability is improved, but axial and radial guidance requirements increase device complexity

Engineering Contradiction:
Improvesealing stabilityVSAvoidguidance mechanism
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines the sealing element with both the drive shaft and the conveying element carrier through material bonding or form-fitting connections. This merging of components eliminates the need for separate axial and radial guidance mechanisms. The sealing element becomes an integrated part of the rotating assembly, using the existing structural connections to maintain its position without requiring additional guidance features, thereby reducing device complexity while maintaining sealing stability.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The sealing element utilizes its own structural integration with the drive shaft and conveying element carrier to maintain its positioning. The material bonding or form-fitting connection allows the sealing element to self-maintain its axial and radial position through the mechanical connection itself, without requiring external guidance systems. The sealing element serves its own guidance function through its integrated design.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP3536961B1Sealing element vacuum pump
Publication Date: 2024.05.01 SCHWABISCHE HUTTENWERKE AUTOMOTIVE CMBH
  • EP3536961B1 patent drawingFigure 1~2
  • EP3536961B1 patent drawingFigure 3~4
  • EP3536961B1 patent drawingFigure 5~6

AI summary

Rotary pump, preferably a vacuum pump, with a pumping chamber (21) having an inlet on a low-pressure side and an outlet on a high-pressure side of the pump (2), a rotor (22) arranged in the pumping chamber (21) and conveying a fluid from the inlet into the pumping chamber (21) to the outlet from the pumping chamber (21), at least one housing part (23, 24) at least axially limiting the pumping chamber (21) and a drive shaft (3) which is connected to the rotor (22) for drive purposes, which includes at least one sealing element (26, 27) connected to the drive shaft (3) and/or the rotor (22) in a displaceable and/or rotationally fixed manner, which forms a radial sealing gap (SD) with the housing part (23, 24).