Rotary Machine Housing Interface for Shaft Vibration Damping

Solution Overview

Problem

Existing rotary machines, such as turbochargers, face vibration and noise issues due to weight unbalance of the rotational shaft, which are not effectively addressed by existing damping solutions that increase complexity and weight.

Innovation Solution

A simple configuration involving a thin-plate member interposed between contact surfaces of the impeller housing, bearing housing, and fastening member in a rotary machine, utilizing friction and collision damping effects to attenuate shaft vibrations, with optional recess portions and fastening mechanisms like snap rings or bolts to enhance damping efficacy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a damping member and an inertial mass body are provided to suppress vibration, then vibration suppression effect is improved, but device complexity and weight increase

Engineering Contradiction:

Improvevibration suppression effectVSAvoidstructure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The invention extracts only the essential friction damping function from complex damping systems. By utilizing the natural friction between contact surfaces of existing components (housing, bearing, fastening member), the patent eliminates the need for separate damping members and inertial mass bodies, achieving vibration suppression with minimal structure modification

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The contact surfaces of existing structural components serve the dual purpose of mechanical support and vibration damping. The friction between these surfaces automatically provides damping without requiring additional active components, making the system self-sufficient for vibration control

Inventive Principle:

Principle #25Self-service

2Reliability

If a damping member and an inertial mass body are provided to suppress vibration, then vibration suppression effect is improved, but weight increases

Engineering Contradiction:

Improvevibration suppression effectVSAvoidoverall weight

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The invention extracts only the essential friction damping function from complex damping systems. By utilizing the natural friction between contact surfaces of existing components (housing, bearing, fastening member), the patent eliminates the need for separate damping members and inertial mass bodies, achieving vibration suppression with minimal structure modification

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The contact surfaces of existing structural components serve the dual purpose of mechanical support and vibration damping. The friction between these surfaces automatically provides damping without requiring additional active components, making the system self-sufficient for vibration control

Inventive Principle:

Principle #25Self-service

3Reliability

If contact surfaces are modified with recess portions to enhance damping, then vibration suppression effect is improved, but manufacturing complexity increases

Engineering Contradiction:

Improvevibration suppression effectVSAvoidmanufacturing simplicity

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

Instead of modifying entire contact surfaces, the invention introduces recess portions only at specific localized areas where they can most effectively enhance friction damping. This selective modification maintains most of the contact surface area while adding minimal manufacturing complexity

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The recess portions create slight backlash and increase friction at critical locations, providing more than sufficient damping effect with minimal material removal. This partial modification approach achieves enhanced damping without the need for extensive surface treatment

Inventive Principle:

Principle #16Partial or excessive action

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 configuration effectively reduces vibration and noise in rotary machines with a low-cost, uncomplicated setup, allowing for higher unbalance allowances and improved production yields without modifying existing structures.

Implementation Method 1

friction occurs between the two contact surfaces, and the friction damping effect attenuates the shaft vibration from the rotational shaft

Methodology Applied

Scientific EffectFriction damping: Friction

Implementation Method 2

slight backlash (micro-vibration in a direction intersecting with the contact surfaces) is more likely to occur between the thin-plate member and the contact surfaces... the shaft vibration from the rotational shaft is attenuated by a collision damping effect

Methodology Applied

Scientific EffectCollision damping: Impact Force

Data Source

PatentUS10934887B2Rotary machine

Publication Date: 2021.03.02 MITSUBISHI HEAVY IND ENGINE & TURBOCHARGER LTD

AI summary

A rotary machine include: a rotational shaft; an impeller mounted to the rotational shaft; an impeller housing accommodating the impeller; a bearing housing accommodating a bearing which supports the rotational shaft rotatably, the bearing housing being fastened to the impeller housing; and a fastening member fastening the impeller housing and the bearing housing in an axial direction of the rotational shaft. The impeller housing, the bearing housing, and the fastening member each includes a contact surface in a direction intersection with an axial direction of the rotational shaft. A thin-plate member formed separately from the impeller housing, the bearing housing, and the fastening member is interposed between at least two of the contact surfaces.