Metering Valve Nozzle Integration for Hydrogen Jet Pump Sealing

Solution Overview

Problem

Frequent opening and closing of metering valves in fuel cell systems lead to wear on the valve seat, impairing sealing tightness and operational efficiency, particularly in jet pump units.

Innovation Solution

The integration of a nozzle into the metering valve within the jet pump unit minimizes pressure losses and optimizes sealing tightness by directly guiding the gaseous medium flow, with a conical through-bore and a diffuser region at the nozzle outlet, and an elastic sealing element to ensure precise control and reduced wear.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the metering valve is frequently opened and closed for optimization of flushing operations and jet pump operation, then the operational flexibility and flushing efficiency are improved, but wear on the valve seat increases and sealing tightness deteriorates

Engineering Contradiction:

Improveoperational flexibilityVSAvoidsealing tightness

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The nozzle is integrated directly into the metering valve body, merging two previously separate components into one unified structure. This integration eliminates the need for separate connections and reduces the number of potential failure points, allowing the valve to maintain sealing tightness even during frequent opening and closing operations.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The valve seat is designed with a conical geometry instead of a traditional flat or cylindrical shape. This geometric parameter change improves the sealing surface characteristics, distributing wear more evenly and maintaining sealing effectiveness over repeated cycling operations.

Inventive Principle:

Principle #35Parameter changes

2Ease of manufacture

If a separate tube connection is used between the metering valve and jet pump unit, then the structural flexibility and ease of assembly are improved, but pressure losses increase due to longer flow paths

Engineering Contradiction:

Improveease of assemblyVSAvoidpressure losses

Core Design Contradiction:

Ease of manufactureVSLoss of energy

Solution Approach 1:

The nozzle is integrated directly into the metering valve body, merging two previously separate components into one unified structure. This integration eliminates the need for separate connections and reduces the number of potential failure points, allowing the valve to maintain sealing tightness even during frequent opening and closing operations.

Inventive Principle:

Principle #5Merging (Combining)

3Ease of manufacture

If the valve seat tolerances are loose to facilitate manufacturing and assembly, then the manufacturing cost and assembly ease are improved, but the sealing tightness at the valve seat deteriorates

Engineering Contradiction:

Improvemanufacturing easeVSAvoidsealing tightness

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The valve seat is designed with a conical geometry instead of a traditional flat or cylindrical shape. This geometric parameter change improves the sealing surface characteristics, distributing wear more evenly and maintaining sealing effectiveness over repeated cycling operations.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The sealing structure utilizes the combination of the conical valve seat geometry and the elastic sealing element material properties to achieve both manufacturing feasibility and high sealing performance.

Inventive Principle:

Principle #40Composite materials

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

This design enhances the sealing tightness and operational reliability of the metering valve and jet pump unit, reducing wear and ensuring smooth, efficient hydrogen flow to the fuel cell, minimizing pressure fluctuations and maintaining optimal performance.

Implementation Method 1

a closure element movable in a reciprocating manner that interacts with a valve seat for opening or closing at least one first through-passage

Methodology Applied

Scientific EffectReciprocating motion:

Implementation Method 2

the through-bore is conical at least in certain portions, and the nozzle and the valve seat are received in the through-bore

Methodology Applied

Scientific EffectConical flow guidance:

Implementation Method 3

a diffuser region at the nozzle outlet

Methodology Applied

Scientific EffectDiffuser region:

Implementation Method 4

an elastic sealing element to ensure precise control and reduced wear

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 5

The ejector unit comprises a feed region, to which a first gaseous medium is fed under pressure, a suction region at which a second medium is present, and a mixing tube region from which a mixture of the first and the second gaseous medium exits

Methodology Applied

Scientific EffectJet mixing: Jet

Data Source

PatentUS11682776B2Metering valve and jet pump unit for controlling a gaseous medium

Publication Date: 2023.06.20 ROBERT BOSCH GMBH

AI summary

The invention relates to a metering valve (1) for controlling a gaseous medium, in particular hydrogen, comprising a valve housing (2), wherein an interior space (3) is formed in the valve housing (2). A reciprocating closing element (10) is arranged in the interior space (3), which interacts with a valve seat (37) for opening or closing at least one passage channel (25). Furthermore, the metering valve (1) comprises a nozzle (11), the at least one passage channel (25) being formed in the nozzle (11) and the passage channel (25) having a circular-cylindrical portion.