Spherical Slipper Retainer for Hydraulic Unit Alignment

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing designs of integrated drive generators face challenges in maintaining efficient operation of hydraulic units due to varying rotational speeds from aircraft engines, which can lead to misalignment and potential damage of components like slipper retainers.

Innovation Solution

A slipper retainer with a circular body and central aperture, featuring a curved surface defined by a sphere and multiple slipper apertures, is designed to securely engage with retainer balls and pistons, ensuring precise contact and alignment, even with varying engine speeds.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If a conventional slipper retainer design is used, then the structure is simple and easy to manufacture, but the component alignment and contact precision deteriorate under varying rotational speeds

Engineering Contradiction:
Improvecontact precisionVSAvoidstructure complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The retainer body incorporates a curved surface defined by a sphere centered at a point located a distance of about 0.209 inches from the back surface of the body. This spherical curvature enables the retainer to maintain proper contact and alignment with the wobbler and piston across varying rotational speeds, resolving the contradiction between manufacturing precision and structural complexity by using a geometrically simple yet functionally effective curved surface.

Inventive Principle:
Principle #14Spheroidality (Curvature)

2Productivity

If the slipper retainer components are designed to mate and fit together precisely, then operational efficiency is improved, but the manufacturing and assembly complexity increases

Engineering Contradiction:
Improveoperational efficiencyVSAvoidassembly ease
Core Design Contradiction:
ProductivityVSEase of manufacture

Solution Approach 1:

The slipper retainer is designed with a circular body configuration that serves multiple functions: it provides the curved surface for wobbler contact, defines the central aperture for piston passage, and creates the slipper apertures for slipper retention. This multi-functional design achieves precise component alignment and improved operational efficiency while avoiding the need for additional separate components, thereby maintaining ease of manufacture and assembly.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If the rotational speed varies during engine operation, then the system adapts to different flight conditions, but the alignment and contact of hydraulic components deteriorates

Engineering Contradiction:
Improvespeed adaptationVSAvoidcomponent alignment
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The curved surface defined by a sphere allows the retainer body to maintain consistent contact and alignment with the wobbler regardless of rotational speed variations. The spherical geometry provides a constant radius of curvature that ensures proper mechanical coupling between components during engine operation across different flight conditions, thereby maintaining reliability while adapting to speed changes.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Data Source

PatentEP3048302B1Slipper retainer for hydraulic unit
Publication Date: 2018.04.18 HAMILTON SUNDSTRAND CORP
  • EP3048302B1 patent drawingFigure 1
  • EP3048302B1 patent drawingFigure 2
  • EP3048302B1 patent drawingFigure 3

AI summary

A slipper retainer 400 of a hydraulic unit having a circular body 401 having a back surface and an outer edge, the circular body defining a diameter of about 2.240 inches (5.629 cm), a central aperture 402 through a center of the circular body, the circular body having a curved surface defining an edge of the central aperture, wherein the curved surface is defined by a sphere that is centered at a point located a distance of about 0.209 inches (0.531 cm) from the back surface of the body, and a plurality of slipper apertures 404 located between the curved surface of the circular body and the outer edge of the circular body, wherein each slipper aperture of the plurality of slipper apertures has a diameter of about 0.464 inches (1.179 cm).