Mixing Cartridge Flow Deflection for Precise Water Temperature Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Thermostatic mixing cartridges without an expansion element exhibit low sensitivity and high hysteresis, making it difficult to set a precise mixed water temperature, which changes significantly with small adjustments and has a delayed, non-linear response.
Innovation Solution
A mixing cartridge design without an expansion element, featuring a control body with adjustable annular sections and tubular extensions that deflect flow paths, allowing for precise adjustment of hot and cold water flow rates, enhancing sensitivity and reducing hysteresis, and compatible with existing thermostatic cartridge housings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a mixing cartridge without an expansion element is used, then the device complexity is reduced and compatibility with existing housings is improved, but the sensitivity is reduced and hysteresis increases
Solution Approach 1:
The control body is segmented into multiple functional sections: a first annular section that limits the cold water inlet to form a radially inward flow path, a second annular section that limits the hot water inlet to form a radially inward flow path, and first and second tubular extensions that deflect the flow paths. This segmentation allows precise control of each water stream independently, improving temperature control precision without requiring an expansion element.
Solution Approach 2:
The patent introduces a radial flow path dimension by having water flow radially inward through annular sections before being deflected into the longitudinal direction by tubular extensions. This dimensional change in flow path configuration enables more precise control over water mixing ratios and improves sensitivity without increasing overall structural complexity.
2Productivity
If the control body is adjusted to change flow rates, then the mixing ratio is improved, but the response time increases due to hysteresis
Solution Approach 1:
The radially inward flow paths through the annular sections ensure continuous and smooth flow of cold and hot water into the mixing chamber. The tubular extensions continuously deflect these flow paths into the longitudinal direction, creating a continuous action that reduces flow interruptions and minimizes hysteresis, thereby improving response time while maintaining effective mixing ratio adjustment.
Solution Approach 2:
The patent utilizes hydraulic principles by designing specific flow path geometries (radially inward paths through annular sections, then deflected by tubular extensions) that optimize water flow dynamics. This hydraulic design ensures smooth, continuous water movement with minimal turbulence and delay, reducing hysteresis effects and improving response time during mixing ratio adjustments.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A mixing cartridge (1) for a sanitary fitting, having: a) a cartridge housing (2) with a first housing part (3) and a second housing part (4), b) a mixing chamber (5) formed in the cartridge housing (2), c) at least one hot water inlet (6) for hot water, extending through the cartridge housing (2) and opening into the mixing chamber (5), d) at least one cold water inlet (7) for cold water, extending through the cartridge housing (2) and opening into the mixing chamber (5), e) at least one mixed water outlet (8) for mixed water, leading out of the mixing chamber (5), f) a control body (9) which can be displaced along a control path (10), the control body (9) having: a first annular portion (11) that delimits, at least partially, the at least one cold water inlet (7) in the cartridge housing (2) in order to form a flow path for the cold water (12), said path running radially inward; a second annular portion (13) that delimits, at least partially, the at least one hot water inlet (6) in the cartridge housing (2) in order to form a flow path for the hot water (14), said path running radially inward; and at least one tubular shoulder (15, 16) which diverts the radially inward-running flow path of the cold water (12) or the radially inward-running flow path of the hot water (14) in the longitudinal direction (17) of the cartridge housing (2).