Stern Drive Cradle Decouples Vibration From Transom
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional stern drive arrangements rigidly attach the drive leg to the marine vessel transom, leading to direct transmission of vibrations and noise, causing discomfort for users due to inadequate vibration isolation.
Innovation Solution
The stern drive employs a cradle device attached to the gimbal ring, housing rubber isolators that pivot with the drive leg, decoupling it from the transom and using elastic vibration dampening mounts to isolate the drive leg from the vessel, thereby minimizing noise and vibration transfer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the drive leg is rigidly attached to the transom, then structural stability and support are improved, but vibration and noise transmission to the vessel increases
Solution Approach 1:
The patent introduces a cradle as an intermediary component between the drive leg and the transom. The cradle decouples the drive leg from direct rigid attachment to the transom, allowing it to pivot and tilt while providing vibration isolation. This intermediary structure maintains structural support while reducing harmful vibration and noise transmission to the vessel.
Solution Approach 2:
The patent changes the mechanical coupling parameters between the drive leg and transom by introducing elastic vibration dampening mounts. These mounts alter the stiffness and damping characteristics of the connection, transforming the rigid attachment into a compliant connection that isolates vibrations while maintaining necessary structural support.
2Object-generated harmful factors
If vibration isolation components are added to decouple the drive leg, then noise and vibration transmission are reduced, but device complexity increases
Solution Approach 1:
The patent merges multiple functions into the cradle structure. The cradle simultaneously provides vibration isolation through elastic mounts, enables steering rotation, allows tilting movement, and supports the drive leg. By combining these functions into a single integrated component rather than separate mechanisms, the patent reduces overall device complexity while achieving effective vibration isolation.
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 solution maintains steering and tilt functionality while effectively isolating the drive leg from the vessel, reducing noise and vibration, and can be retrofitted to existing stern drives without altering the transom or drive configuration.
Implementation Method 1
housing rubber isolators that pivot with the drive leg
Implementation Method 2
using elastic vibration dampening mounts to isolate the drive leg from the vessel
Data Source
AI summary
A stern drive for a marine vessel comprises a gimbal housing that is configured for connection to the transom of the marine vessel; a gimbal ring that is steerable with respect to the gimbal housing about a vertical steering axis; a drive leg that is trimmable with respect to the gimbal ring about a horizontal trim axis, wherein the drive leg supports a propulsor for propelling the marine vessel; a trim actuator that is configured to trim the drive leg about the trim axis; and a cradle that decouples the drive leg from the transom of the marine vessel and pivots with and supports the drive leg and as the trim actuator trims the drive leg about the trim axis.