Propeller Shaft Bearing Layout for Easier Marine Propulsion Maintenance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing propulsion units have complex bearing arrangements for propeller shafts, which complicate maintenance and require drydocking for component replacement.
Innovation Solution
A propulsion unit design featuring a radial bearing positioned axially between elastic biasing means and a thrust bearing, with a large circumferential support area and flexible supporting structure, allowing for a simple construction and easy maintenance without drydocking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a complex bearing arrangement is used for the propeller shaft, then the support reliability is improved, but the device complexity increases and maintenance difficulty increases
Solution Approach 1:
The patent combines the radial bearing and thrust bearing into a single integrated bearing arrangement. The radial bearing is positioned axially between the elastic biasing means and the thrust bearing, creating a compact unified structure that supports both radial and axial loads on the propeller shaft, thereby reducing overall device complexity while maintaining support reliability.
Solution Approach 2:
The bearing arrangement is designed to perform multiple functions simultaneously: the radial bearing provides radial support, the thrust bearing handles axial loads, and the elastic biasing means provides both positioning and compensation functions. This multi-functional design reduces the need for separate components, simplifying the overall structure while ensuring reliable support.
2Reliability
If a complex bearing arrangement is used for the propeller shaft, then the support reliability is improved, but the ease of repair deteriorates
Solution Approach 1:
The bearing arrangement is divided into distinct modular segments: the radial bearing, the thrust bearing, and the elastic biasing means are positioned as separate but integrated components. This segmentation allows individual components to be inspected, removed, and replaced independently, significantly improving ease of repair and maintenance while maintaining overall support reliability.
Solution Approach 2:
The radial bearing is extracted and positioned axially between the elastic biasing means and the thrust bearing, creating a configuration where components can be accessed and removed separately. This extraction approach enables maintenance personnel to service individual bearing components without dismantling the entire propulsion unit, facilitating easier repair operations.
3Device complexity
If the radial bearing is positioned axially between elastic biasing means and thrust bearing, then the device complexity is reduced, but the manufacturing precision requirements increase
Solution Approach 1:
The elastic biasing means acts as an intermediary element between the radial bearing and the thrust bearing. This elastic component provides a compliant interface that can accommodate minor manufacturing tolerances and positioning variations, reducing the stringency of manufacturing precision requirements while maintaining the simplified axial positioning of the radial bearing.
Solution Approach 2:
The use of elastic biasing means introduces flexibility into the axial positioning system. The elastic deformation capability of the biasing means allows for parameter adjustment and compensation, enabling the radial bearing to be positioned accurately in the axial direction even with moderate manufacturing tolerances, thereby reducing overall manufacturing precision requirements.
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
Facilitates a simpler bearing arrangement that reduces sensitivity to bending and enables easy inspection and replacement of components, enhancing maintenance efficiency.
Implementation Method 1
the elastic biasing means 30 loaded slide pieces 12 of the thrust bearing 8 are preferably, but not necessarily, configured to resiliently yield axially X-X
Implementation Method 2
The elastic biasing means 30 loaded slide pieces 12 of the thrust bearing 8 are preferably, but not necessarily, configured to at least partly resiliently resist tilting such as to resiliently resist excess tilting of the collar 11 in the bearing house 9
Implementation Method 3
a circumferential surface 13 of the collar 11 is rotatably supported on an annular sliding surface 14 of the radial bearing 10 in the bearing house 9
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Presented is a propulsion unit comprising a housing supported with a support arm on a hull, a propeller shaft (4). The propeller shaft has an axis of rotation and is rotatably supported with a first bearing (5) and with a second bearing. The first bearing comprising a thrust bearing (8) positioned and supported in a bearing house (9), and a radial bearing (10) that is a sliding bearing. The first bearing comprising a collar (11). Opposite side surfaces of the collar is rotatably supported in the bearing house on elastic biasing means (30) loaded slide pieces (12) of the thrust bearing. The radial bearing is positioned and supported in the bearing house, and the radial bearing is positioned axially at least partly between the elastic biasing means loaded slide pieces.