Modular Hydrant Nozzle Cap for Accurate Leak Vibration Detection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Fire hydrant leak detection systems face challenges in accurately distinguishing between leak-induced vibrations and background noise, and the existing solutions are often costly and require replacing the entire nozzle cap, which is not economically viable for all users.

Innovation Solution

A modular nozzle cap for fire hydrants featuring a cap body with an inner housing and an outer housing that houses a vibration sensor, allowing for easy replacement and integration of a metal insert for improved vibration detection, reducing false alarms and eliminating the need for potting electronic components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a leak detection system is integrated into the nozzle cap, then leak detection capability is provided, but the cost increases and customers who do not desire leak detection must purchase an expensive cap

Engineering Contradiction:

Improveleak detection capabilityVSAvoidcost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The nozzle cap is divided into separate functional modules: a base cap structure and a removable outer housing containing the vibration sensor and electronics. This segmentation allows customers to purchase only the base cap if leak detection is not needed, or add the sensor module separately, reducing overall system cost while maintaining detection capability for those who need it.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The outer housing is designed as a universal module that can be attached to or removed from the base cap. This multi-functional design allows the same housing to serve either as a simple protective cover for basic caps or as an integrated leak detection system when equipped with vibration sensors, accommodating different customer needs and price points.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Ease of manufacture

If the outer housing is made from plastic material, then cost is reduced and corrosion resistance is improved, but structural strength and vibration detection accuracy deteriorate

Engineering Contradiction:

ImprovecostVSAvoidvibration detection accuracy

Core Design Contradiction:

Ease of manufactureVSMeasurement precision

Solution Approach 1:

The outer housing utilizes composite construction combining plastic material with integrated metal components (such as metal inserts or metal-reinforced sections). This composite approach maintains the corrosion resistance and cost benefits of plastic while incorporating metal elements that provide the necessary structural strength and vibration conduction properties for accurate leak detection.

Inventive Principle:

Principle #40Composite materials

3Reliability

If pressure equalization ports are provided, then pressure changes are equalized to protect components, but moisture and undesirable elements can enter the cavity

Engineering Contradiction:

Improveprotection from pressure changesVSAvoidmoisture entry

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The cavity is sealed with a flexible membrane or diaphragm that allows pressure equalization while blocking moisture and contaminants. This flexible barrier responds to pressure changes by flexing inward or outward, equalizing pressure differential across the seal, yet maintains a continuous protective barrier against moisture and undesirable elements entering the electronic cavity.

Inventive Principle:

Principle #30Flexible shells and thin films

4Reliability

If the entire nozzle cap is replaced with a leak detection system, then leak detection is achieved, but cost and complexity increase significantly

Engineering Contradiction:

Improveleak detection capabilityVSAvoidsystem complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The leak detection system is segmented into a removable outer housing module that contains only the essential vibration sensor and minimal electronics, attached to a separate base cap. This segmentation reduces overall system complexity by allowing the detection functionality to be added as a discrete module rather than redesigning the entire cap assembly, making the system easier to manufacture and maintain.

Inventive Principle:

Principle #1Segmentation

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

Enhances leak detection accuracy by filtering out background noise and allowing for cost-effective upgrades to existing nozzle caps, reducing the risk of damage from pressure changes and moisture exposure.

Implementation Method 1

Leaks within the fluid systems can send vibrations through the fluid system and up the stand pipes to the fire hydrants. These vibrations propagating through the stand pipes and fire hydrants can be monitored to detect leaks within the connected fluid system.

Methodology Applied

Scientific EffectVibration detection: Vibration

Implementation Method 2

Methodology Applied

Scientific EffectVibration filtering: Vibration

Data Source

PatentUS11473993B2Hydrant nozzle cap

Publication Date: 2022.10.18 MUELLER INT LLC

AI summary

Example aspects of a nozzle cap for a fire hydrant and a method for manufacturing a nozzle cap to detect leaks in a fluid system are disclosed. The nozzle cap for a fire hydrant can comprise a cap body, the cap body comprising an inner housing and an outer housing, the outer housing defining a cavity; a vibration sensor received within the cavity and configured to detect leaks in a fluid system connected to the fire hydrant; and a metal insert contacting the vibration sensor and the inner housing.