Non-Coaxial Thermostatic Mixer Layout for Compact Sanitary Fittings

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Solution Overview

Problem

Sanitary fittings with thermostatic mixers require significant space, which is often not available, and existing solutions do not reliably maintain a consistent mixed water temperature due to fluctuations in hot water supply and pressure, posing risks of scalding and inconsistent water delivery.

Innovation Solution

A sanitary fitting design featuring a thermostatic mixer with an expansion element and slide that adjusts the mixing ratio between cold and hot water, allowing for compact installation by non-coaxial arrangement, reducing the space required while maintaining consistent hot water temperature through adjustable gap widths in the mixing valve.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a thermostatic mixing valve is installed upstream of the hot water inlet to maintain constant temperature, then the hot water temperature stability is improved, but the installation space requirement increases

Engineering Contradiction:
Improvehot water temperature stabilityVSAvoidinstallation space
Core Design Contradiction:
ReliabilityVSVolume of stationary object

Solution Approach 1:

The thermostatic mixing valve is integrated within the existing mixing valve housing, with the expansion element and slide valve arranged in a nested configuration where the expansion element is positioned within the same housing space as the slide valve. This allows the thermostatic mixing function to be added without requiring additional external installation space.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The expansion element and slide valve are arranged non-coaxially, with the expansion element positioned laterally adjacent to rather than along the same axis as the slide valve. This non-linear arrangement optimizes space utilization within the cylindrical housing by utilizing radial space rather than requiring extended axial space.

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

2Device complexity

If the expansion element and slide valve are arranged coaxially, then the structural simplicity is improved, but the installation space increases

Engineering Contradiction:
Improvestructural simplicityVSAvoidinstallation space
Core Design Contradiction:
Device complexityVSVolume of stationary object

Solution Approach 1:

The expansion element and slide valve are deliberately arranged in an asymmetric, non-coaxial configuration. The expansion element is positioned offset from the central axis of the slide valve, creating an asymmetric layout that reduces the overall space requirement while maintaining functional effectiveness.

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

Instead of arranging components along the same axial dimension, the expansion element is positioned in a lateral dimension adjacent to the slide valve. This dimensional reorganization allows both components to coexist within a more compact volume by utilizing three-dimensional space more efficiently.

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

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

The solution allows for a compact thermostatic mixer installation that maintains consistent mixed water temperature, reducing the risk of scalding and ensuring reliable water delivery while optimizing space usage.

Implementation Method 1

The thermostatic mixer (4) comprises an expansion element (5) and a slide valve (6) actuated by the expansion element for setting a mixing ratio between the cold water and the hot water

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentEP3868964B1Sanitary fitting with a non-axial thermostatic mixer
Publication Date: 2022.11.02 GROHE AG
  • EP3868964B1 patent drawingFigure 1~2
  • EP3868964B1 patent drawingFigure 3~5
  • EP3868964B1 patent drawingFigure 4

AI summary

Sanitary fitting (1), comprising at least: - a fitting body (2); - a mixing valve (3) for mixing cold water and hot water to form a mixed water; and - a thermostatic mixer (4) for mixing cold water and hot water to form the hot water, comprising a thermal expansion element (5) and a slide (6) actuated by the thermal expansion element (5) for setting a mixing ratio between the cold water and the hot water, wherein the thermal expansion element (5) and the slide (6) are not arranged coaxially to each other.