Shaft Seal Test Stand with Air-Gap Thermal Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing test devices for shaft seals lack efficient temperature control and dynamic measurement capabilities, and are limited in their ability to accurately measure friction torque due to contact-based thermal transfer and interference from ball bearings.

Innovation Solution

A test device with a chamber housing featuring annular grooves for non-contact temperature control, a rotatably mounted shaft connected to an electric motor, and a brake system for precise friction torque measurement, utilizing a Peltier element for efficient temperature regulation and a lever mechanism to detect deflection, allowing for dynamic measurements and relative friction torque analysis.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If contact-based thermal transfer is used to control temperature, then temperature control is achieved, but thermal resistance increases and temperature control efficiency decreases

Engineering Contradiction:
Improvetemperature control efficiencyVSAvoidthermal resistance
Core Design Contradiction:
TemperatureVSLoss of energy

Solution Approach 1:

The patent introduces air as an intermediary medium between the housing and chamber housing. The air gap allows thermal energy to be transferred from the housing to the chamber housing without direct physical contact, eliminating the thermal resistance that would occur with contact-based thermal transfer while maintaining effective temperature control of the oil and chamber housing.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Speed

If ball bearings are used to support the shaft, then rotational movement is achieved, but interference with friction torque measurement occurs

Engineering Contradiction:
Improverotational movementVSAvoidfriction torque measurement
Core Design Contradiction:
SpeedVSMeasurement precision

Solution Approach 1:

The patent removes the ball bearing from the system entirely. Instead of supporting the shaft with a ball bearing that interferes with measurements, the shaft is supported directly by the housing structure, eliminating the source of measurement interference while still enabling rotational movement of the shaft.

Inventive Principle:
Principle #2Taking out (Extraction)

3Stability of the object's composition

If the chamber housing mass is increased for stability, then stability improves, but dynamic measurement capabilities decrease

Engineering Contradiction:
Improvechamber housing stabilityVSAvoiddynamic measurement capability
Core Design Contradiction:
Stability of the object's compositionVSSpeed

Solution Approach 1:

The patent divides the housing structure into separate components: a stationary housing and a rotatable chamber housing. The chamber housing is supported on air bearings that provide stability while allowing rapid rotation. This segmentation enables the chamber housing to have low mass for dynamic measurements while the stationary housing provides structural stability.

Inventive Principle:
Principle #1Segmentation

4Temperature

If physical contact is used for thermal transfer, then heat transfer is achieved, but device complexity increases due to additional contact components

Engineering Contradiction:
Improveheat transferVSAvoidthermal transfer components
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent uses air as a simple intermediary medium for thermal transfer between the housing and chamber housing. This eliminates the need for complex contact-based thermal transfer components such as heat exchangers or thermal conductors, reducing device complexity while maintaining effective heat transfer capability.

Inventive Principle:
Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables efficient temperature control of the chamber housing and oil, precise measurement of friction torque, and relative change analysis, improving the dynamic measurement capabilities and reducing interference, while allowing for comparison of different oils and tribological systems.

Implementation Method 1

A temperature control unit having a Peltier element is arranged on the housing

Methodology Applied
Scientific EffectPeltier effect: Peltier Effect

Implementation Method 2

The annular grooves create a large surface area on the chamber housing, which faces a corresponding inner surface area, particularly with an air gap of constant radial width. This results in low thermal resistance, enabling heat to be transferred between the housing and the chamber housing without physical contact.

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 3

a brake is provided, wherein the shaft is connected to a brake which is supported directly or by means of a torque support element on the support element

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 4

the shaft is supported by means of a bearing, in particular a ball bearing, on the support part

Methodology Applied
Scientific EffectBall bearing: Ball Bearing

Data Source

PatentEP3785005B1Device, in particular testing device, and test stand
Publication Date: 2022.07.13 SEW EURODRIVE GMBH & CO KG
  • EP3785005B1 patent drawingFigure 1
  • EP3785005B1 patent drawingFigure 2
  • EP3785005B1 patent drawingFigure 3

AI summary

The invention relates to a device, in particular a testing device, having: a chamber housing; a shaft-sealing ring; a shaft; a bearing, in particular ball bearing; a brake; a supporting part; and a shaft part, in particular a shaft part which can be rotated by a motor. The shaft-sealing ring which is arranged, in particular runs, on the shaft part is accommodated in the chamber housing. The chamber housing is connected for conjoint rotation with the shaft, more particularly is formed integrally with the shaft. The shaft is mounted rotatably by means of the bearing, the bearing being accommodated in the supporting part. The shaft is connected to a brake which is supported on the supporting part directly or by means of a torque-supporting part. In particular, the shaft is connected for conjoint rotation with a first part of the brake, and a second part of the brake is connected to the supporting part directly or by means of a torque-supporting part.