Ram Piston Overload Assembly With Additive Burst Disc Forces

Solution Overview

Problem

Existing hydraulic tools face issues with burst disc leakage and reduced fatigue life due to opposing hydraulic pressure reaction and supporting forces, leading to misalignment and inefficient sealing.

Innovation Solution

An integrated overload assembly within the ram piston or manifold of the hydraulic tool, where hydraulic pressure reaction force and supporting force act in the same direction, enhancing sealing and reducing fatigue on the burst disc.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the supporting force on the burst disc is increased to achieve a larger resulting force for sealing, then the sealing efficiency is improved, but the fatigue life of the burst disc is reduced

Engineering Contradiction:

Improvesealing efficiencyVSAvoidfatigue life of burst disc

Core Design Contradiction:

ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The invention inverts the conventional force arrangement by positioning the lock nut and spacer such that the supporting force and hydraulic pressure reaction force act in the same direction rather than opposite directions. This is achieved by placing the lock nut at the opposite end of the ram cavity from the burst disc, with the spacer between them, creating additive forces that seal the burst disc without increasing the supporting force magnitude.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The invention changes the dimensional arrangement of forces from a one-dimensional opposing force system to a one-dimensional additive force system by repositioning components along the axial direction of the ram cavity. This dimensional reconfiguration allows both forces to contribute constructively to sealing the burst disc.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Reliability

If the supporting force on the burst disc is increased to prevent leakage, then the sealing efficiency is improved, but misalignment and reduced sealing efficiency occur due to force opposition

Engineering Contradiction:

Improvesealing efficiencyVSAvoidalignment of burst disc

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The invention inverts the conventional force arrangement by positioning the lock nut and spacer such that the supporting force and hydraulic pressure reaction force act in the same direction rather than opposite directions. This is achieved by placing the lock nut at the opposite end of the ram cavity from the burst disc, with the spacer between them, creating additive forces that seal the burst disc without increasing the supporting force magnitude.

Inventive Principle:

Principle #13The other way round (Inversion)

3Adaptability or versatility

If a conventional overload assembly with lock nut and spacer is used, then the hydraulic tool can burst the overload assembly at high pressure, but leakage occurs at the burst disc due to opposing forces

Engineering Contradiction:

Improveoverload protection capabilityVSAvoidsealing at burst disc

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The invention inverts the conventional force arrangement by positioning the lock nut and spacer such that the supporting force and hydraulic pressure reaction force act in the same direction rather than opposite directions. This is achieved by placing the lock nut at the opposite end of the ram cavity from the burst disc, with the spacer between them, creating additive forces that seal the burst disc without increasing the supporting force magnitude.

Inventive Principle:

Principle #13The other way round (Inversion)

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 improves sealing efficiency and extends the burst disc's lifespan by maintaining consistent forces, even at high pressures, thereby preventing leakage and misalignment.

Implementation Method 1

hydraulic pressure can be created in the ram chamber, by which a hydraulic pressure reaction force acts on the lock nut and a supporting force from the lock nut acts on the burst disc

Methodology Applied

Scientific EffectHydraulic pressure: Pressure Increase

Data Source

PatentUS12397407B2Hydraulic tool having ram piston with integrated overload assembly

Publication Date: 2025.08.26 MILWAUKEE ELECTRIC TOOL CORP

AI summary

Embodiments of the invention provide a ram assembly for a hydraulic tool. The ram assembly includes a ram piston having a ram cavity. The ram piston receives a hydraulic pressure reaction force. The ram assembly further includes an overload assembly disposed in the ram cavity or in a cavity defined by a manifold. The overload assembly includes a burst disc positioned at a first end of the ram cavity or manifold, a lock nut positioned at a second end of the ram cavity or manifold, and a spacer positioned between the burst disc and the lock nut. The spacer transfers a supporting force applied to the lock nut to the burst disc. The hydraulic pressure reaction force and the supporting force both act in the same direction, and thus, are additive forces acting on the burst disk.