Segmental Thrust Bearing Assembly for Planetary Gear Symmetry

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing axial plain bearings for planetary gears are costly and difficult to assemble due to their design, and they cannot be used identically on both sides of a planetary gear due to structural differences.

Innovation Solution

The axial plain bearing is designed with separate, one-piece segments that absorb axial forces in one direction, featuring wedge or tilting surfaces with sliding pairs and lubricant-filled gaps, allowing easy assembly and identical use on both sides of the planetary gear.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If axial plain bearings are designed with separate one-piece segments, then ease of manufacture and assembly is improved, but structural complexity increases

Engineering Contradiction:
Improveease of manufactureVSAvoidstructural complexity
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The axial plain bearing is divided into multiple separate one-piece segments that can be manufactured independently and assembled together. Each segment functions as an independent bearing element with wedge surfaces, allowing standardized mass production while maintaining functional integrity when assembled in sequence around the rotational axis.

Inventive Principle:
Principle #1Segmentation

2Productivity

If identical axial plain bearings are used on both sides of a planetary gear, then productivity and cost-effectiveness are improved, but the bearing design becomes more complex to accommodate bidirectional force requirements

Engineering Contradiction:
ImproveproductivityVSAvoidbearing design complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The axial plain bearing design incorporates multiple segments with wedge surfaces that can be arranged to handle axial forces in either direction. By using identical bearing assemblies on both sides of the planetary gear, the system achieves bidirectional force absorption capability through the segmented structure, eliminating the need for different bearing designs while maintaining manufacturing efficiency.

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

3Force

If wedge surfaces are introduced to absorb axial forces, then load-bearing capacity is improved, but manufacturing precision requirements increase

Engineering Contradiction:
Improveload-bearing capacityVSAvoidwedge surface precision
Core Design Contradiction:
ForceVSManufacturing precision

Solution Approach 1:

The wedge surfaces are distributed across multiple separate segments rather than requiring a single complex precision-machined component. This segmentation allows each segment to be manufactured with standard precision tolerances, and the cumulative effect of multiple segments provides the necessary load-bearing capacity, reducing the stringency of individual manufacturing precision requirements.

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

This design enables cost-effective manufacturing and assembly, while allowing identical bearings to be used on both sides of a planetary gear, enhancing operational efficiency and reducing production costs.

Implementation Method 1

The two sliding surfaces of a pair of sliding surfaces are rotatable relative to each other and slide against each other during rotation. A gap between the sliding surfaces is preferably filled with lubricant, so that fluid or mixed friction occurs between the sliding surfaces.

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 2

The sliding surfaces of a sliding surface pair of an axial plain bearing are designed to transmit forces to each other at least in the axial direction.

Methodology Applied
Scientific EffectNormal force: Mechanical Force

Implementation Method 3

A gap between the sliding surfaces is preferably filled with lubricant, so that fluid or mixed friction occurs between the sliding surfaces.

Methodology Applied
Scientific EffectFluid friction: Lubrication

Data Source

PatentEP3973199B1Segmental thrust bearing
Publication Date: 2025.08.06 ZF FRIEDRICHSHAFEN AG
  • EP3973199B1 patent drawingFigure 1
  • EP3973199B1 patent drawingFigure 2

AI summary

The invention relates to a thrust bearing having at least two one-piece segments (105) that are physically separate from each other. At least one segment (105) has at least one wedge-shaped surface (103) that serves as the sliding surface.